from cradle to grave sustainability metrics

sustainability metrics from cradle to grave

Mendoza, Argentina March 24-27 2013

Proceedings of the Vth International Conference on Life Cycle Assessment, CILCA2013

Copyright @ Facultad Regional Mendoza, Universidad Tecnológica Nacional, 2013. Todos los derechos de este volumen están reservados. Sólo está permitida la reproducción parcial o total con fines Académicos siempre que se mencione el origen.

Primera edición: Marzo de 2013

Diseño de Tapa: Gabriela Barón (UTN) Logotipo de Tapa: Mercedes Civit (Ludwig Morris)

ISBN 978-950-42-0146-5

Editores

Alejandro Pablo Arena Bárbara Civit Roxana Piastrellini

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Impreso en la Argentina

- Printed in Argentina

Queda hecho el depósito que previene la ley 11.723

Responsabilidades: El contenido y opiniones vertidas en los trabajos incluidos en este libro son responsabilidad de sus respectivos autores.

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Proceedings of the V International Conference on Life Cycle Assessment - CILCA2013

CILCA 2013, Mendoza, Argentina March 24th- 27 th, 2013

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Sustainability metrics, from cradle to grave

Organización General Alejandro Pablo Arena (chair) Bárbara Civit (co-chair)

Comité Organizador Francesc Castells Pique (Universidad de Rovira i Virgili, España)

Elena Rosa (Univ. Central de las Villas, Cuba)

Joan Rieradevall Pons (Sostenipra Universidad Autónoma de Barcelona, España)

Isabel Quispe (Pontificia Univ. Católica del Perú)

Nydia Suppen Reynaga (CADIS, México)

Carlos Naranjo (GAISA, Colombia)

Cassia M. L. Ugaya (UTFPR, Brasil)

Alejandro Pablo Arena (UTN FRM, Argentina)

Armando Caldeira Pires (Univ. de Brasilia, Brasil)

Sonia Valdivia (UNEP, Francia)

Barbara Civit (UTN FRM, Argentina)

Gil Anderi da Silva (Univ.de Brasilia, Brasil)

Liliana Niveyro (FCA UNCuyo, Argentina)

Ana Quiros (Ecoglobal, Costa Rica)

Pablo Martínez (CNEA, Argentina)

Claudia Peña (CIMM, Chile)

Fernando Mele (UNT, Argentina)

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Comité Científico Francesc Castells Pique (España)

Isabel Quispe (Perú)

Mary Ann Curran (USA)

Sonia Valdivia (Francia)

Martina Prox (Alemania)

Joan Rieradevall Pons (España)

Carlos Naranjo (Colombia)

Sangwon Suh (USA)

Alejandro Pablo Arena (Argentina)

Mark Goedkoop (Holanda)

Barbara Civit (Argentina)

Fernando Mele (Argentina)

Nydia Suppen Reynaga (México) Cassia M. L. Ugaya (Brasil) Armando Caldeira Pires (Brasil) Gil Anderi da Silva (Brasil) Ana Quiros (Costa Rica) Claudia Peña (Chile) Elena Rosa (Cuba)

James Fava (USA) Llorenc Mila i Canals (Inglaterra)

Jorge Hilbert (Argentina)

Maite Aldaya (Francia)

Miguel Brandao (España)

Greg Norris (USA)

Edmundo Muñoz (Chile)

Thomas Koellner (Alemania)

Patricia Güereca (México)

Claudio Zaror (Chile)

Comité Local Alejandro Pablo Arena (UTN/CONICET)

Andrés Benito (UTN)

Enrique Puliafito (UTN/CONICET)

Eugenio Fisicaro (UTN)

Bárbara Civit (UTN/CONICET)

Liliana Niveyro (UNCuyo)

Roxana Piastrellini (UTN/CONICET)

Cecilia Rébora (UNCuyo)

José Luis Córica (UTN)

Andrea Rivarola (UTN)

Magalí García (UTN)

María Celeste Gardey (UTN)

Luisa Baumhauer (UTN)

Claudia Kolosow (UTN)

Silvia Curadelli (UTN)

Paula Díaz Ortiz (UTN)

Juan Nuñez Mc Leod (UTN)

Gabriela Barón (UTN)

Miriam López (UTN)

Cuerpo de Revisores Alejandro Pablo Arena

Anna Lucia Mourad

Celina Rosa Lamb

Alfredo Iriarte Garcia

Armando Caldeira Pires

Claudia Peña

Amalia Sojo

Assumpció Antón

Ana Quiros

Barbara María Civit

Claudio Alfredo Zaror Zaror

Anderi da Silva

Cassia M. L. Ugaya

David Gabriel Allende 6


Elena Rosa

Joan Rieradevall Pons

Pablo Martinez

Fausto Freire

Leonor Patricia Guereca

Fernando Daniel Mele

Llorenc Mila i Canals

Paulo Sergio Moreira Soares

Francesc Castells Pique

Luiz Kulay

Gabriela baron

Maite Aldaya

Gerardo Javier Arista

María Dolores Bovea

Ronaldo Francisco Santos Herrero

Greg Norris

Miguel Brandão

Roxana Piastrellini

Irma Mercante

Mireya Gonzalez

Sangwon Suh

Isabel Quispe

Montserrat Nunez

Silvia Palma Rojas

J Adolfo Almeida Neto

Nydia Suppen Reynaga

Rafael Rafael Pazeto Alvarenga

Comunicación Elba Pescetti (UTN/CONICET) Florencia Ruggeri (UTN)

Gestión tecnológica Javier Gustavo Gitto (UTN) José Luis Córica (UTN)

Diseño Mercedes Civit (Ludwig Morris) Gabriela Barón (UTN FRM)

Compaginación Juan Nuñez Mc Leod

Protocolo Silvana Scarpetta (UTN FRM)

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PROLOGO En nombre del Comité Organizador de la V Conferencia Internacional sobre Análisis de Ciclo de Vida – CILCA 2013, ponemos a su disposición estas Actas que recopilan las contribuciones de los distintos autores que han hado sustancia a este evento. Desde la primera edición en Costa Rica en el año 2005, CILCA se ha convertido en una conferencia periódica, bien establecida, y reconocida a nivel internacional, que provee un marco para la difusión del conocimiento generado en los grupos de investigación, en las consultoras y en las empresas, quedando disponible para toda la comunidad. Pero no es eso lo más importante, sino el marco que brinda para la reunión, discusión, cooperación y generación de nuevas ideas, que impulsan edición tras edición nuevos proyectos y publicaciones conjuntas. En este proceso de consolidación y crecimiento, CILCA incorpora nuevas actividades y ofrece una mayor variedad de opciones para sus participantes. Opciones no sólo académicas, sino también recreativas que ayudan a hacer más “sostenible” Cilca, a través del establecimiento y reforzamiento de relaciones. Este año, el vino mendocino será protagonista de las actividades recreativas, con visitas a bodegas, degustaciones y cenas. A los ya clásicos cursos, sesiones técnicas orales y poster, conferencias plenarias y Mesas redondas, este año sumamos la realización de un Taller para Doctorandos, que ofrece a los tesistas un ámbito de discusión e intercambio de experiencias que enriquecerá sus trabajos de investigación con el aporte de expertos en los temas abordados.. Confiamos en que disfruten de este material tan valioso, y del exigente programa propuesto. A los que no pudieron participar del evento, esperamos que estas memorias les sean útiles, y nos auguramos encontrarlos en el próximo CILCA. Alejandro Pablo Arena Bárbara Civit Marzo de 2013

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FOREWORD On behalf of the Organizing Committee of the V International Conference on Life Cycle Assessment - CILCA 2013, we provide these proceedings which collect the contributions of the various authors, the marrow of this event. Since the first edition in Costa Rica in 2005, CILCA has become a periodic conference, well established and internationally recognized, which provides a framework for the dissemination of knowledge generated by the research groups, consulting firms, and technical centres. But the most important thing is the framework provided for the meeting for discussion, cooperation and generation of new ideas that drive year after year new projects and joint publications. In this process of consolidation and growth, CILCA incorporates new activities and offers a wider range of options for its participants. Options not only academic, but also recreational that help make Cilca more "sustainable", through the establishment and strengthening of networks. This year, the recreational activites will feature a starring role by the wine from Mendoza: the visits to wineries, wine tastings, lunch at Altavista winery and dinner accompanied with good wine are some of the optional activities included. To the classic courses, oral and poster technical sessions, plenary lectures and panel discussions, this year we added a PhD Workshop, which offers postgraduate students a space for discussion and exchange of experiences that will enrich their research with input from experts in the topics. We hope you enjoy this valuable material, and the demanding program we propose. For those unable to attend the event, we hope these memories will be useful, and we hope we will meet them in the next CILCA. Alejandro Paul Arena Barbara Civit March 2013

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CONTENTS FULL PAPERS ................................................................................................20 Carbon and Water footprints ...........................................................................21 A new method for assessing impacts of water use in life cycle assessment .......22 Farm-gate environmental decision tool ...............................................................27 Study of embodied energy and CO2eq.as eco-efficiency descriptors of Brazilian building materials ...............................................................................................41 Modeling carbon footprint of the Chilean apple production .................................50 Carbon Footprint of Three Walls Systems in Low Cost Housing in Colima, Mexico ...........................................................................................................................54 Assessing water footprint of companies in Colombia .........................................63 Water and energy consumption at KAUST and how to reach a null water footprint ...........................................................................................................................74 Rice water footprint in paddy systems of Entre Ríos ..........................................80 Organization´s carbon footprint ..........................................................................91 Kraftliner paper – A temporary carbon stock packaging material ........................98 The water footprint and water use efficiency in vineyards-Mendoza, Argentina 103 Design for sustainability ................................................................................110 Contribution of Simplified LCA to Design for Sustainability – Cases of Industrial Application .......................................................................................................111 Ecolabelling, Environmental Product Declarations Type III (PCREPD) and green purchasing ...........................................................................................125 Communicational strategy for environmental aspects to promote the consumption of sustainable products ....................................................................................126 Comparison between European EPD issuing Systems and lessons learned to Latin American Countries .................................................................................137 Education and Capability Development .......................................................150 Life Cycle approach and use of softwares in the chain of Brazilian biodiesel ....151 UndeRstandable methOdology Bonding KnOwledge from cRadle-to-cradle for Undergrad Students: UROBORUS ...................................................................158 Industrial Ecology ..........................................................................................168 Proposal for technical and environmental performance improvement actions at an electricity cogeneration plant within the sugar/alcohol sector............................169 Industrial Symbiosis in the Industrial Area of Villa El Salvador .........................175

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LCA & Rural Development .............................................................................183 Carbon payback times for petrodiesel substitution by palm biodiesel from expansion of plantations in Brazilian Amazon ..................................................184 Life cycle impact assessment of cotton production in the Brazilian Savanna ....189 Anthropogenic phosphorus emissions inventory in China .................................196 LCA & Sustainable Cities...............................................................................215 Tool for environmental analysis of domestic water use in buildings and urban environments ...................................................................................................216 The State of the Art of LCA in the PCCI context in Brazil .................................223 Integrating LCA in the selection of strategies for reducing the energy demand in Mexican social housing ....................................................................................234 Comparative Life Cycle Assessment of a Retrofit Housing Project and a Suburban Housing Development in the Metropolitan Area of Mexico City ........239 Comparative evaluation of brt (bus rapid transit) and lrt(light rail transit) systems: life cicle simulation using the gabi software tool ...............................................245 Life Cycle Assessment of the Brazilian diesel consumption: Effects of sulfur reduction ..........................................................................................................252 LCA Case Studies ..........................................................................................260 Environmental Study of the Sugar and Bioethanol Industry based on Sugarcane by using a Life-Cycle Assessment Approach. A Case Study in the Northwestof Argentina..........................................................................................................261 Nitrous Oxide Emissions from Agricultural Soils: Effects on the Environmental Profile of Soybean Biodiesel.............................................................................267 Urea formaldehyde resin: impacts on the productive life cycle of wood based panels ..............................................................................................................274 Carbon footprint of an integrated management system for restaurants and catering waste considering uncertainty .............................................................282 Carbon footprint of beef production in a brazilian south farm ............................295 Life Cycle Assessment of Bioethanol Production from Eucalyptus globulus: Comparison of Solvent Extraction and Dilute Acid Hydrolysis ..........................309 LCA as a tool of Decision making process for the Environmental Improvement of wastewater treatment in Latin American and the Caribbean: the case of activated sludge technology ............................................................................................326 Life cycle assessment of solid biofuel production from microalgae with CO2 fixation in cement plants ...................................................................................333 Life Cycle of a School Power Station with Combined Renewable Fuels - Avoided CO2 Emissions Estimated with CDM ...............................................................345 Life Cycle Assessment of Brazilian Biodiesel ...................................................352

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Multi-Step Decision Making on Life Cycle Assessment Methods for Industrial Sectors .............................................................................................................358 Environmental and Socioeconomic LCA of Milk in Canada ..............................366 Comparative LCAs of ceramic tiles and bricks vs concrete equivalents in the Brazilian context ...............................................................................................378 Sustainability assessment of chemical processes and/or products using life cycle assessment ......................................................................................................384 Life Cycle Assessment of the CILCA 2007 event .............................................396 Life cycle assessment of Chilean copper wire rods ..........................................402 Energy balance of IVS 4500 wind turbine through a Life Cycle Assessment ....409 Life cycle analysis of handmade ceramic brick in chiapa de corzo, chiapas, mexico .............................................................................................................422 Life cycle assessment of corn-based ethanol via dry milling in Province of Santa Fe, Argentina ...................................................................................................428 Analysis of the procedures for allocation criteria and the system boundaries in LCA: study case of a toothbrush ......................................................................434 Evaluation of the dicalcium phosphate process with a view to environmental performance improvement identification ...........................................................441 LCA-based comparison of different scenarios of the application of a novel ceramic nanofiltration membrane in the pulp industry .......................................447 Allocation in Brazilian milk production: a case study .........................................452 Importance of dry matter intake on environmental impacts of Brazilian milk production: a case study ..................................................................................456 Life-cycle evaluation of the ceramic block with a focus on social interest housing .........................................................................................................................460 LCA of lighting products: looking for methodological consistency .....................472 Comparison of different methods for vinasses treatment from the bioethanol industry based on LCA .....................................................................................480 Life cycle assessment applied to technology for the remediation of contaminated sites: a case study with chemical oxidation ......................................................490 LCI & LCA Databases.....................................................................................497 The need for consequential system modelling in Life Cycle Assessment for robust decision support ...............................................................................................498 LCADB.sudoe: Life Cycle Inventories database of the southwest of Europe ....507 LCIA ................................................................................................................514 Life Cycle Impact Assessment on the land use impacts and application of Geographic Information Systems .....................................................................515 Incorporation Of Risks Analysis Into The Lca Methodology: Challenges In Petroleum Production .......................................................................................526 12


LCM and Eco-efficiency .................................................................................533 Development of a methodology for the integration of nutritional and environmental aspects for sustainable food consumption .................................534 The environmental evaluation of alternatives for energy improved performance in printing and writing paper production by way of Life Cycle Analysis (LCA) .......543 Driving product stewardship: an empirical evaluation of the association between some form of LCA implementation and environmental strategy choice in Colombian firms ...............................................................................................548 Life Cycle Management of Products in Embraer: challenges and persperctives .........................................................................................................................558 Systematic Monetization and Integration of environmental Impacts in planning processes.........................................................................................................566 Life Cycle Costing ..........................................................................................574 Economic and environmental impacts assessment along the supply chain of anhydrous ethanol from sugarcane in Brazil .....................................................575 Social Responsibility and Life Cycle Sustainability Assessment ...............584 Studying the Social Hotspots of 100 product categories with the Social Hotspots Database..........................................................................................................585 Social Life Cycle Assessment of Brick Production in El Algarrobal, Mendoza, Argentina: Preliminary Selection of Indicators ..................................................594 Framework for social life cycle impact assessment ..........................................600 Managing issues of responsibility across the entire product life cycle: Towards an integrative model from the resource-based view of the firm and stakeholder theory ...............................................................................................................608 Environmental and Economic Hybrid Life Cycle Assessment of Bagasse-Derived Ethanol Produced in Brazil ...............................................................................629 Sustainability evaluation of biodiesel production using Life Cycle Assessment performed with a specific Sustainability Index at Rio Grande do Sul, Brazil ......638 The use of aggregation step in Social Life Cycle Assessment: cocoa's soap case study ................................................................................................................650 Sustainable Resource Management .............................................................658 Improvement of the Energy Balance of Microalgae Biodiesel by Integration with anEthanol Distillery ..........................................................................................659 Environmental viability assessment of soybean ethyl ester in vehicle use ........670 The state of the art on calculating abiotic resource depletion ...........................676 Material assessment beyond geological availability ..........................................682 LCA of logs extracted by forest management in Amazonian rainforests ...........687 Estimating CO2 emissions in the employees transportation service of an agricultural sector .............................................................................................693 13


Waste Management and Recycling ...............................................................699 Uncertainties in modelling impacts from the application on agricultural land of processed organic waste..................................................................................700 Sustainability Assessment of Chemical Processes and/or Products using Life Cycle Assessment............................................................................................706 The Clean Development Mechanism in Wastewater Treatment Plants: The Case of Latin America and the Caribbean .................................................................718 Environmental impact allocation methods and their reflection on the attractiveness of blast furnace slag in cement industry .....................................725

ABSTRACTS .................................................................................................731 LCA Case Studies ..........................................................................................732 Land Use in drylands: Desertification risk assessment. An agricultural case study .........................................................................................................................733 Management of whey in small dairy industries. A life cycle analysis .................735 Waste Management and Recycling ...............................................................737 Use of garlic herbaceous waste as a fiber source on growing Rabbits .............738

POSTERS ......................................................................................................740 Carbon and Water Footprints ........................................................................741 Green Water Footprint for agricultural exports from the Province of Buenos Aires .........................................................................................................................742 Water Footprint and Life Cycle Assessment frameworks: synergies and hurdles .........................................................................................................................752 Water footprint of soybean under different tillage practices ..............................753 Effect of water recovery on the water footprint of cellulose production in Chile .754 Sustainability analysis of the Colombian flower industry: LCA, environmental indicators and benchmarking............................................................................756 Carbon footprint of the Chilean raspberry production .......................................758 Water footprint of the tourism sector in Chacras de Coria, Mendoza, Argentina .........................................................................................................................759 Carbon footprint of beers of a small processing plant in Chile ..........................760 Water footprint of a cattle breeding production system in the Argentine Pampa .........................................................................................................................761 Design for Sustainability ...............................................................................763 Application of Life Cycle Assessment in Enhancing the Environmental Characterization of Materials for Ecodesign .....................................................764 14


Calculation of the ecological footprint of concrete. A tool for sustainable design .........................................................................................................................774 Redesign of a portable water treatment plant ...................................................784 LCA applied case: Strategic Analysis for a Sustainable traveling exhibition .....786 Balancing Ecology & Economy – A case study.................................................788 Ecodesign (ISO 14006) and Environmental Management Systems (ISO 14001): specifications, comparisons and organizational advantages of its integration ...789 Proposition of LCA - and LCC- based eco-efficiency indicators for selection of concrete building structural components ..........................................................790 Life cycle assessment of temporary structures: A framework for decision making and evaluation..................................................................................................792 Inventory Of Life Cycle Of The Polymer Phb- Polyhydroxybutyrate ..................794 Education and Capability Development .......................................................795 Implementation of LCA in Poland .....................................................................796 Laboratory of Life Cycle Assessment of Energy Systems at the IEE-USP ........806 Empirical guidelines to reduce errors in LCA data gathering process ..........807 Green Economy and Sustainable Policies ...................................................808 Factores inherentes al Análisis de Ciclo de Vida: recomendaciones de política .........................................................................................................................809 Sustainability Policies in Tourism Protected Areas. Case: Archipelago Los Roques National Park ......................................................................................818 Operationalising sustainability: current industrial practice .................................819 Life cycle sustainability of wind power in Brazil ................................................820 Pilot Project: Neutralization of Emissions from Agribusiness through Afforestation and Reforestation .............................................................................................821 Inherent factors to Life Cycle Assessment: policy guidelines ............................822 Industrial Ecology ..........................................................................................823 Sustainable assessment of the pervaporation process for bioethanol dehydration using an LCA-based approach ...................................................824 LCA & Rural Development .............................................................................826 Life Cycle Assessment As A Tool To Assess The Sustainability Of Cocoa In Colombia ..........................................................................................................827 Biodigestors And Lca – A Contribution To The Pig Farming’s Sustainability – The Case Of Santa Catarina (Brazil) .......................................................................831 LCA & Sustainable Cities...............................................................................832 Quantifying the environmental value of building reuse......................................833 Cumulative energy demand estimation of SIP (structural insulated panels) homes through LCA .....................................................................................................834 15


Life Cycle Assessment of social interest housing in Mexico .............................835 LCA of housing in Chile ....................................................................................836 LCA Case Studies ..........................................................................................837 Home and ready-made meals ..........................................................................838 Beyond Carbon Footprinting for Corporate Activities – LCA vs. Carbon Footprint of a Canadian Bank ..........................................................................................844 Life cycle assessment of Miscanthus pellet production in Ireland .....................850 LCA application in the water footprint dairy chain. Argentina case study ..........851 Life Cycle Impacts Assessment as a support for risks management: the case of chemotherapy drug waste in a Brazilian hospital ..............................................852 Trade off between operating cost increment and Carbon market income due to life cycle greenhouse gases emissions reduction .............................................853 Preliminary study on the environmental profile of bioethanol production from Spartina argentinensis. Inventory phase ..........................................................855 Environmental impact assessment of mercurial sludge generated from Chloralkali Cuban plant by means of Life Cycle Analysis: Disposal or Remediation?856 Environmental impacts of used cooking oil: direct wastewater treatment or transportation to Biodiesel production plants? ..................................................858 LCA-based hotspot analysis of food products to inform major Chilean retailer’s sustainability strategy .......................................................................................859 Management of whey in small dairy industries. A life cycle analysis .................861 Life Cycle Assessment of Electric Cars in Portugal ..........................................863 Life Cycle Energy Analysis Of Rainwater Harvesting System With Reservoir Made Of Reinforced Concrete ..........................................................................864 Modeling the Consequential Life Cycle Assessment of Brazilian Biodiesel .......865 Energy Balance Analysis And Life Cycle Energy Assessment Of Sugarcane Bagasse Ethanol Production And Electricity Generation...................................867 Definition of the allocation rules in the PCR of basic metals based on a case study ................................................................................................................869 Life cycle assessment of cellulose production from pine and eucalyptus wood in Chile .................................................................................................................871 LCA methodology to guide Green Process Innovation: A case study of Brazilian MDF industry ....................................................................................................872 Potentiality of Life Cycle Assessment to determine points of inefficiency in agribusiness systems: a case study for the sugar and ethanol agro industry of Tucumán ..........................................................................................................873 Life Cycle Assessment applied to a clothing product ........................................874 Handprints: The Positive Counterpart to Footprints ..........................................875 16


Life Cycle Assessment of Concrete Blocks Masonry: Processes Contribution Analysis............................................................................................................876 Big Affect from Little Wooden Tongue Depressors ...........................................877 Comparison between internal combustion and electric vehicles in Brazil using Life Cycle Assessment............................................................................................878 Life cycle assessment of Jatrophacurcas cultivation in tropical regions destinated to biodiesel production .....................................................................................879 Environmental Evaluation of an Intensive Production System in the Central Basin of Argentina employing the Extended Life Cycle Assessment (LCA) ................881 Physic-mechanical and environmental comparison of Compressed Earth Blocks stabilized with cement and lime ........................................................................882 Post-consumer PET bottles Life Cycle Inventory (LCI) in Mexico .....................883 LCI & LCA Databases.....................................................................................885 LCA of Buildings in Mexico: Advances, Limits and Catalysts ............................886 Life Cycle Inventory Of Milk Production At An Experimental Unit In Itapetinga – BA ....................................................................................................................891 The World Food LCA Database (WFLDB) project: towards more accurate food datasets ...........................................................................................................896 Life cycle inventory of electronic waste treatment: Brazilian case .....................897 LCA-based tools for data collection and data processing towards a National Life Cycle Inventory for the Chilean Food & Agriculture Sector ...............................898 Estimating environmental impacts by means of FADN data. Comparison with horticultural LCA results ...................................................................................900 Life Cycle Assessment of soybean oil in Brazil .................................................902 Inventory of ammonia emission (NH3) from livestock production in Chile .........903 The transportation of oil in biodiesel production in Bahia / Brazil and its importance in Life Cycle Assessment ...............................................................904 The influence of transportation modal in the life cycle of copper in Brazil .........905 LCIA ................................................................................................................906 Urea formaldehyde resin: impacts on the productive life cycle of wood panels .907 Soybean Oil’s Enviromental Impacts andLand .................................................908 The use of optional elements of the Life Cycle Impacts Assessment: literature review ..............................................................................................................909 LCM and Eco-efficiency .................................................................................910 Life Cycle Management of chemicals – How far are we? .................................911 Life Cycle Costing ..........................................................................................912 Life cycle cost analysis of four bioclimatic strategies aimed at saving water and energy in direct evaporative cooling equipment ................................................913 17


Social Responsibility and Life Cycle Sustainability Assessment ...............915 Excessive Caribbean Medical Traveling: Analysis and Suggestions for a Lower the Carbon Footprint ........................................................................................916 Sustainable Resource Management .............................................................917 LCA of locally produced feeds for Peruvian aquaculture ..................................918 Potential environmental impacts of the production of antivenom immunoglobulins in a brazilian official laboratory .........................................................................920 Water consumption analysis for Life Cycle Assessmentin a dairy cattle farm ...921 Energy consumption analysis in a dairy cattle farm ..........................................922 Waste Management and Recycling ...............................................................923 Life Cycle Concept in Waste Management in the Oil & Gas Offshore Exploration Activities ...........................................................................................................924 Life Cycle Inventory of Municipal Solid Waste Incineration (MSWI) in Spain and Portugal............................................................................................................933 Car recycling management in the frame of LCM...............................................941 Recovery of manganese from spent alkaline batteries: use of MnOx as catalyst for VOCs elimination ........................................................................................942 Municipal Solid Waste Management: A Regional Proposal ..............................943 Effects of biodynamic preparations on the development of compost from manure and agroindustrial residues ............................................................................944 LCA- C&DW: An environmental assessment tool in the waste management of the construction sector ...........................................................................................946 LCA as a tool of Decision making processfor the Environmental Improvement of wastewater treatment in Latin American and the Caribbean .............................947 Life Cycle Assessment of Integrated Management of PET bottles generated in the municipality of Ecatepec de Morelos ..........................................................948 Improving the Utilization of Garlic Herbaceous Waste in the Diet of Breeding Cows ................................................................................................................950 Life Cycle Assessment of Municipal Solid Waste Management of San Miguel, Buenos Aires, Argentina...................................................................................951

DOCTORAL WORKSHOP ...........................................................................952 Integración de ACV y técnicas de optimización. Caso de estudio: Bioetanol a partir de maíz ...................................................................................................953 El Valor Intangible Del Desarrollo Tecnológico: Aspectos Ambientales ............955 Análisis de Ciclo de Vida de la Gestión de los Residuos Sólidos Urbanos de San Miguel, Buenos Aires, Argentina ......................................................................958 Análisis del Ciclo de Vida del Manejo Integral de las botellas de PET que se generan en el Municipio de Ecatepec de Morelos ............................................960 18


Technological Parametrized Lifecycle Analysis Method For Wall Insulation .....962 Energía y Huella de Carbono de Edificios Habitacionales en México: Escenarios de Mitigación Ante el Cambio Climático ...........................................................966 Envolventes De Hormigon Liviano Sustentable: Diseño Y Propiedades Para El Ahorro Energetico ............................................................................................969

PLENARY CONFERENCE ..........................................................................971 La Comunicación Estratégica del Pensamiento de Ciclo de Vida desde la perspectiva regional y mundial .........................................................................972 Global LCI for primary copper ..........................................................................974 From foundations to the building - a blueprint of LCA in Mexico .......................975 The Bhutan-UN International Project to Create a New Paradigm for Sustainable Development ....................................................................................................976 Interoperability in LCA: problems and solutions ................................................977 Contributing To Rio+20: A Unep/Setac Life Cycle Sustainability Assessment Approach..........................................................................................................978

ROUND TABLE .............................................................................................980 PCR Guidance Development Process and its Importance to the Latin American Region .............................................................................................................981 Product category rules in emerging regions: the global trade of mineral raw materials ..........................................................................................................988 The development of Product Category Rules in order to ensure a Green Economy in emerging regions ..........................................................................990

ADDENDUM………………………………………………………………….. 998 Consistent calculation of multiple system models and improved integration of regionalized data in a background inventory database………………………….. 999

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FULL PAPERS

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Carbon and Water footprints

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A new method for assessing impacts of water use in life cycle assessment Markus Berger1)*, Ruud van der Ent2), Vanessa Bach1), Korbinian Brochnow1), Matthias Finkbeiner1)

1)

Technische Universität Berlin

Department of Environmental Technology, Chair of Sustainable Engineering Office Z1, Strasse des 17. Juni 135,10623 Berlin, Germany

+49.30.314-25084 [email protected] 2)

Delft University of Technology

Department of Water Management, Faculty of Civil Engineering and Geosciences, Delft, The Netherlands

Abstract Freshwater scarcity is of increasing concern in many parts of world but still often neglected in LCAs of water intense products such as food or biofuels. In this work a new method for inventorying water use and assessing local impacts is presented. On the inventory level, the basin internal evaporation recycling is determined based on meteorological studies leading to recycling ratios of 0 – 23% and, thus, causes a new definition of water consumption. The water deprivation index is introduced as a new midpoint indicator allowing for a regional impact assessment in more than 10,000 watersheds or on the country level. In contrast to previous impact assessment methods, this indicator is set to the highest level per se in regions with low precipitation and saline groundwater. In addition to a ratio of annual water consumption to renewability rate and indexes assessing sensitivity of local population and ecosystems, sensitivity to additional water consumption as well as ground- and surface water stocks are taken into account for the first time in an impact assessment method. Since regional water flows are the only inventory requirement, this method allows for an easy applicable and robust assessment of consequences resulting from local water consumption. Keywords: water use, water consumption, life cycle impact assessment, water footprint

Introduction Freshwater scarcity is an increasing problem for humans and ecosystems in many parts of the world. Despite this global challenge, water use is often ignored in LCAs of water intense products, such as food, biofuels, or renewable raw materials, due to a lack of awareness, data, and applicable impact assessment methods. After reviewing existing water footprint methods(Berger and Finkbeiner 2010), applying them in industrial case studies(Berger et al. 2012), and identifying methodological challenges(Berger and Finkbeiner 2012), this work aims at developing a new inventory and impact assessment method for water use. 22


Methods The new methodology comprises an inventory and impact assessment framework. Inventory On the inventory level, freshwater withdrawals, wastewater discharges as well as evapo(transpi)ration and synthetical water from chemical reactions are considered (Figure 1).

Figure 1:

Water inventory

Until recently, evaporated water was regarded as lost, i.e. consumed, for the originating watershed. However, recent studies on continental evaporation recycling showed that large fractions of evaporation are recycled within relatively short time and length scales(van der Ent et al. 2010; van der Ent and Savenije 2011). Therefore, the amount of evaporation recycling within a watershed is determined by means of the basin internal evaporation recycling (BIER) ratio. 𝐸𝑅𝑖 = 𝐸𝑖 ∙ 𝐵𝐼𝐸𝑅𝑖 (1) Based on the methodology for calculating continental evaporation recycling described in van der Ent et al. (2011), evaporation recycling ratios within radii of 25, 50, 75, 100, 200, and 500 km are calculated for each raster point. Depending on the size of the watershed, evaporation recycling ratios are assigned to the watershed by averaging values of the raster within the watershed: 

Awatershed< 1964 km²  evaporation recycling value of r = 25 km (A= 1964 km²)



1964 km² 785398 km² evaporation recycling value of r = 500 km (A= 785398 km²)

Consequently, water consumption (WC) is defined as freshwater withdrawals minus wastewater discharges and evaporation recycling (equation 2). 𝑊𝐶 =

𝐹𝑊𝑖 − 𝑊𝑊𝑖 − 𝐸𝑅𝑖

(2)

𝑖

Impact assessment Impacts resulting from water consumption are determined by multiplying the water consumption in each 23


watershed (i) with the local water deprivation index (WDI) serving as a generic characterization factor to address areas of protection human health, ecosystem quality and resources (equation 3) 𝑊𝐹𝑖𝑚𝑝𝑎𝑐𝑡 =

𝑊𝐶𝑖 ∙ 𝑊𝐷𝐼𝑖

(3)

𝑖

As shown in equation 4, WDI is based on a ratio of annual water consumption (AWC) to renewability rate (RR), which is frequently used as a scarcity ratio in water footprint methods. Data are derived from the waterGAP 2.2 model (Alcamo et al. 2003). 𝑊𝐷𝐼 =

𝐴𝑊𝐶 𝑅𝑅 + 𝑆𝑊𝑆𝑎𝑢

2

∙ 𝐴𝐹𝐺𝑊𝑆 ∙ 𝑆𝐼 (4)

However, this ratio overestimates water scarcity as only the renewable supply (groundwater recharge and surface run-off) are considered which neglects the compensation ability of ground and surface water stocks.

Therefore, annually usable surface water stocks (SWSau) are added to the renewable supply. In contrast to run-offs, surface water stocks are not renewed on an annual basis. For that reason SWS au is determined as 1% of the effective surface water stocks (SWSeff). According to equation 5, SWSeff is determined for each watershed in waterGAP 2.2 by multiplying the area of surface water bodies (ASWB), i.e. lakes and wetlands, with their effective depth (deff)and by adding the volumes of reservoirs (V reservoir). For lakes an effective depth of 5 m and for wetlands an effective depth of 2 m is assumed. 𝑆𝑊𝑆𝑒𝑓𝑓 =

𝐴𝑆𝑊𝐵 ,𝑖 ∙ 𝑑𝑒𝑓𝑓 ,𝑖 + 𝑉𝑟𝑒𝑠𝑒𝑟𝑣𝑜𝑖𝑟 ,𝑖

(5)

𝑖

As groundwater stocks cannot be quantified on a global level, adjustment factors (AF GWS) for groundwater availability are introduced. Based on data from the WHYMAP (BGR 2012), adjustment factors are defined based on geological structure and annual recharge as follows: 

Major groundwater basin, very high recharge (> 300 mm): 0.900



Major groundwater basin, high recharge (100 - 300 mm): 0.925



Complex hydrogeological structure, very high recharge (> 300 mm): 0.950



Complex hydrogeological structure, high recharge (100 - 300 mm): 0.975

In order to account for sensitivity to additional water consumption, the denominator is squared leading to the effect that ratios of 1/10 are regarded more severe than ratios of 1,000/10,000. Finally, a sensitivity index (SI) is implemented to account for vulnerability of human health (SIhh) and ecosystems (SIes) to water stress (equation 6). 𝑆𝐼 = 𝑆𝐼𝑕𝑕 + 𝑆𝐼𝑒𝑠

(6)

𝑆𝐼𝑕𝑕 = 1 − 𝐻𝐷𝐼

(7)

𝑆𝐼𝑒𝑠 = 𝑁𝑃𝑃𝑤𝑎𝑡 −𝑙𝑖𝑚

(8)

While sensitivity of human health is estimated by means of the human development index (UNDP 2012) (equation 7), ecosystem sensitivity isdetermined as the share of net primary production which is limited by water availability (NPP wat-lim) (equation 8). Data for NPPwat-limis taken from(Pfister et al. 2009), who revealed a significant linear regression between net primary production andvascular plant species diversity used as an indicator for ecosystem quality. Berger and Finkbeiner (2012) discussed artifacts of other impact assessment methods (e.g. (Frischknecht et al. 2009; Pfister et al. 2009), that regions are considered not water scarce, simply as there is no consumption due to low population density and an absence of agriculture/industry. That‘s why the WDI is set to the highest 24


value automatically in areas with low rainfall (< 200 mm/a) and regions with saline groundwater (> 5 g/l TDS) and rainfall below 400 mm/a.

Results and discussion Inventory The BIER ratios, denoting the fraction of evaporation recycled within a watershed, are shown in Figure 2. As it can be seen, results differ significantly between catchments ranging from 0% on small islands to more than 20% in the Congo basin. Thus, the location of evaporation is very important for determining the actual water consumption and results may differ significantly if evaporation recycling is considered or not. Besides the size of the watershed, meteorological conditions determine the evaporation recycling as discussed in van der Ent et al. (2011).

Figure 2

Basin internal evaporation recycling (BIER) ratios in the watersheds

Impact assessment Water deprivation indexes serving as characterization factors were calculated on country and watershed level and are currently under refinement. In contrast to other midpoint indicators, WDI is highest in arid regions like the Sahel zone, in which conventional midpoint impact assessment methods indicate low water stress resulting from low water use due to the absence of population and industry. Moreover, sensitivity to additional water consumption is taken into account by squaring the denominator in equation 4. For the first time, ground- and surface water stocks are taken into account in addition to renewable supplies. Consequently, scarcity in regions with large surface water stocks, such as Scandinavia or the Amazonas basin is reduced. As such regions are usually under low water stress anyway when considering pure consumption to renewability ratios, the difference to dry regions, showing high consumption to renewability ratios and low ground- and surface water stocks, is increased further. By considering sensitivity of local population and ecosystems, socio-economic and biological aspects are taken into account, which are relevant for assessing impacts on human health and ecosystems. The new inventory and impact assessment methods are currently tested in a case study of Latin American and European biofuel production.

Conclusion A new method for assessing effects of freshwater consumption in LCA has been developed. On the inventory 25


level, the basin internal recycling of evaporation is considered, reducing water consumption up to 23% depending on the location. WDI serves as characterization factor and allows for regional impact assessment of water consumption in more than 10,000 watersheds or on the country level. In contrast to previous midpoint indicators, WDI is highest in regions with low precipitation, considers sensitivity to additional water consumption and acknowledges local ground and surface water stocks. As only regional water inventories are required, this approach provides a robust and easily applicable way of determining impacts from water consumption.

Acknowledgements The authors would like to express sincere thanks to Martina Flörke and Stephanie Eisner from the Center forEnvironmental Systems Research (CESR) at the University ofKassel for providing data from the waterGAP 2.2 model. Further we would like to thank Andrea Richts and Wilhelm Struckmeier from the Federal Institute for Geosciences and Natural Resources for fruitful discussions.

References Alcamo, J., P. Döll, T. Heinrichs, F. Kaspar, B. Lehner, T. Rosch, and S. Siebert. 2003. Development and testing of the WaterGAP 2 global model of water use and availability. Hydrol. Sci. J. 48(3): 317-337. Berger, M. and M. Finkbeiner. 2010. Water footprinting - how to address water use in life cycle assessment? Sustainability 2(4): 919-944. Berger, M. and M. Finkbeiner. 2012. Methodological challenges in volumetric and impact oriented water footprints. J. Ind. Ecol. (in press DOI: 10.1111/j.1530-9290.2012.00495.x). Berger, M., J. Warsen, S. Krinke, V. Bach, and M. Finkbeiner. 2012. Water Footprint of European Cars: Potential Impacts of Water Consumption along Automobile Life Cycles. Environ. Sci. Technol. 46(7): 4091-4099. BGR. 2012. WHYMAP http://www.whymap.org/whymap/EN/Home/whymap_node.html. Accessed 08 November 2012. Frischknecht, R., R. Steiner, and N. Jungbluth. 2009. The Ecological Scarcity Method - Eco-Factors 2006 - A method for impact assessment in LCA. Bern, Swizerland: Federal Office for the Environment. Pfister, S., A. Koehler, and S. Hellweg. 2009. Assessing the environmental impacts of freshwater consumption in LCA. Environ. Sci. Technol. 43(11): 4098-4104. UNDP. 2012. Human development reports http://hdr.undp.org/en/statistics/. Accessed 08 November 2012. van der Ent, R. J. and H. H. G. Savenije. 2011. Length and time scales of atmospheric moisture recycling. Atmos. Chem. and Phys. 11: 1853-1863. van der Ent, R. J., H. H. G. Savenije, S. Bettina, and S. C. Steele-Dunne. 2010. Origin and fate of atmospheric moisture over continents. Water Res. Research 46.

26


Farm-gate environmental decision tool Maria José Amores 1,*, Assumpció Antón Duaigües3, Francesc Castells1 1

1,2

, Francesc Ferrer3, Orene Cabot3, Antoni Baltiérrez3, Albert

Departament d'EnginyeriaQuímica, UniversitatRovira i Virgili, Campus Sescelades,

Av. Països Catalans 26, 43007 Tarragona, Spain 2

IRTA (Institute for Food and Agricultural Research and Technology),

Ctra. Cabrils km 2, 08348 – Cabrils, Barcelona, Spain 3

Centre d‘AssessoriaLabFerrer.c/FerranCatòlic, 3

25000 Cervera, Lleida, Spain

*Corresponding author: María José Amores Departamentd'Enginyeria Química, Universitat Rovira i Virgili, Campus Sescelades, Av. Països Catalans 26, 43007 Tarragona, Spain

Tel: +34 977 55 85 53, Fax: +34 977 55 96 21 e-mail: [email protected]

Abstract Purpose:

Irrigated agriculture faces the need of improving the agricultural, water and carbon management practices by doing an on-site performance evaluation or strategic assessment of farm water management practices. A methodological approach was followed to develop an operational tool that makes possible to generate an on-farm simple inventory that may be used to calculate environmental sustainability indicators (carbon and water footprint) as well as to provide assessment to the farms‘ managers to make strategic and tactical decisions. Methods:

The scope of the project was to set up an operational procedure at a farm level to evaluate agronomic and environmental water use as well as carbon footprint indicator. Testing the operability & facility of the implementation of this procedure, a set of commercial pilot farms" located in the Ebro Basin (NE Spain), were used as pilot operational cases. The applied method included inventory, accounting procedures and environmental impact assessment. In order to assess the carbon footprint, the calculator included farm tasks, fertilizers and chemical treatments, transport and distribution, irrigation and commercialization. Results:

The end product was a web-based application (so called, efoodprint), where the user enters field27


measured data and the efoodprint‘s algorithms conduct environmental and sustainable calculations based on the three defined approaches (agronomical, water and carbon) and related indicators as carbon and water footprint. Concerning water and carbon footprint results, they were structured in two sections: (I) agronomic and environmental water assessment and (II) carbon emissions assessment. Conclusions:

This work presents an attempt to implement an inventory procedure at a farm management unit level with the aim of quantifying and assessing the impact of irrigation in term of water footprint as well as contribution to global warming by carbon footprint in order to integrate them into the managers‘ dashboard to make strategic decisions. The tool was user-friendly and generic enough to be applied in different cropping systems and agricultural areas of the world, enabling to generate simple reports with the results of the analysis. This software could become a useful tool for third parts in the supply chain for evaluating and benchmarking their fresh products providers (agro-producers), based on objective parameters, in terms of water use sustainability and carbon dioxide equivalent emissions. Outlook: Additional on-site agronomic issues would be taken into account in the future, like the estimation of realistic on-site leaching fractions, inclusion of information regarding the concentration of solutes in the irrigation and drainage water the aridity of the climate and the adjustment of the crop coefficient to the specific conditions of the farm management unit. Key words: carbon footprint, water footprint, agriculture, environmental software, decision making, water use sustainability.

1 Introduction Societal concern about environmental problems has increased the demand for reliable information and tools to understand and mitigate environmental damage. One of the biggest water problems around the world is scarcity and so on, in many regions, water supplies are not sufficient to satisfy all agricultural, industrial, urban and environmental demands (Jefferies et al. 2012). Irrigated agriculture faces the need to improve water management practices from consumption (quantity and quality), resources (energy and water) and of course, environmentally (water and soil) which has to be in concordance with the economic and social sustainability of the farming activity. Agriculture places a serious burden on the environment in the process of providing humanity with food(FAO 2003). On average, it is the largest consumer of water(70% of global freshwater

consumption and almost 86% of all water used in the world is to grow food (UNESCO-WWAP 2009)) and the main source of nitrate pollution of groundwater and surface water, as well as the principal source of ammonia pollutionand contributor to the phosphate pollution of waterways (OECD 2001). Moreover, agriculture is a significant contributor to land degradation and to the release of thepowerful anthropogenic global greenhouse gas emissions (GHG), being responsible for 25% of

carbon, 50% of methane and more than 75% of nitrous oxide emitted annually by human activities (Tubiello et al. 2007)due to the emissions from nitrogen fertilizers and fossil resources consumption 28


(IPCC 2001).

The agri-food sector should take the responsibility towards implementing environmental freshwater conservation actions and develop tools to achieve these productive environmental challenges. Several environmental indicators have been developed in order to assess the farm practices. Often, these indicators become too much complicated (OECD 2001) for the farmer or in other cases, they become too much general/global assessments and then, they are very simplified (Butchart et al. 2010) for the farmer specific assessment. Hence, one of the answers to satisfy this demand has been the appearance in the market of environmental calculators focus mainly in water and carbon footprint and developed as simplifiedlife-cycle management tools to simulate systems and support decision making for producers.

Water Footprint (WF) and Carbon Footprint (CF) are two approaches to measure the environmental impact on water consumption and Global Warming Potential, respectively, from consumer products taking life-cycle perspective (Morrison et al. 2010). The concept of ‗water footprint‘ introduced by Hoekstra et al. (2003) and subsequently elaborated by (Hoekstra et al. 2009, 2011)provides a framework to analyze the link between human consumption and the appropriation of the freshwater resources that incorporates both direct and indirect water use of a consumer or producer. Recently, it is being developed an international standard for water footprint by the International Organization for Standardization (ISO 14046).The carbon footprint refers to the sum of greenhouse gas (GHG) emissions caused by an organization, event or product and is expressed in terms of CO2 equivalents (IPCC, 2007). So, global warming potential is the most widely studied impact category due to the initiatives taken by agri-food businesses (i.e. supermarket chains) who defense the use of carbon footprints (CF) since agricultural activities contribute 10-12% of GHG globally (Smith et al. 2007). International standards such as ISO 14047 provide guidelines in the framework of Life Cycle Assessment to calculate CF. Also specific standards such PAS 2050.1(BSI 2011)or the coming from World Resources Institute (WRI 2012)and the World Business Council for Sustainable Development (WBCSD) provide specifics guides to measure the carbon footprint of horticultural and agricultural products respectively. To be useful to the farm manager, some indexes needs to be calculated for each Farm Management Unit (FMU) at the end of the season to help assessing its strategy, by benchmarking the FMUs performance, thinking about changes or improvements that may have a beneficial impact on the crop and water use performance of the farm. To be able to steer irrigation management along the growing season and make tactical decisions, reliable information should be obtained at different scales (FMUs, farm and watershed).

Given that the growing in importance for WF and CF in so many studies in agri-food sector, it becomes essential to select these two indicators to assess our study. Many studies on food and agricultural products have been published accounting water footprint indicator (Ridoutt et al. 2009; Ercin et al. 2011; Jefferies et al. 2012; Mekonnen and Hoekstra 2010a; Mekonnen and Hoekstra 2011),carbon footprint indicator (Torrellas et al. 2012; Gan et al. 2012a;Gan et al. 2012b;Ma et al. 29


2012; Ingram and Thomas Fernandez 2012; Cellura et al. 2012; Hillier et al. 2009; Maheswarappa et al. 2011; Pathak et al. 2010; Röös et al. 2010; Vázquez-Rowe et al. 2012; Cerutti et al. 2010; Bosco et al. 2011; Point et al. 2012) or both, water and carbon footprint (Page et al. 2012; Stoessel et al. 2012; Chapagain et al. 2006).

Recently, some calculators have been proposed in order to assess carbon and water footprint. The Water Footprint Network published an Extended calculator (Hoekstra et al. 2005) which helps the user to know how much water uses day by day (water requirements per unit of product). In the field of agricultural practices, the most relevant published tools for sustainability assessment have been the Fieldprint calculator(Alliance 2012), which evaluates how crop production operations affect the sustainability at farm level (CF and WF assessment) and the Cool farm tool calculator (Unilever 2010), a greenhouse gas calculator for farming, including emissions from fields, inputs, livestock, land use and land use change and primary processing. Following the principle of parsimony ―as simple as possible and as complex as necessary‖(Pidd 1996), a simplified and combined tool of water and carbon footprints for agri-food products has been developed to provide better insights into key environmental issues for the farmers.

In order to combine all these fields, we propose a software-calculator (called MUSA) for accounting and assessing on-farm environmental sustainability indicators in irrigated agriculture based on water and carbon footprint as well as realistic field data. Then, our approach for MUSAtool goes beyond previous cited tools and considers a life-cycle approach of operations within a farm, including the direct and indirect uses of water. To include these indicators of environmental to be used into the practice decision making scheme of farming we include some indexes related to: environmental of water consumption (consumptive-based volumetric water footprint and stressweighted water footprint), agronomic of water use (irrigation, energy use efficiency, water use efficiency…), irrigation scheduling management (uniformity coefficient irrigation, effective precipitation…) and global warming contribution (carbon footprint). This efoodprint-calculator presents an attempt to implement an inventory procedure at a Farm Management Unit level with the aim of obtaining real on-site values (instead of being estimated from generic databases) of production, water use and environmental indicators to quantify and assess the impact of irrigation, and to integrate it into the managers‘ dashboard to make strategically decisions. The aim is to account and assess on-farm environmental sustainability indicators in irrigated agriculture based on the water footprint and the LCA methodology as well as realistic field data. In this study, the environmental calculator was used to analyze three case studies.As pilot cases, we propose the assessment of three crops (grape, nectarine and corn grain). The collected data have been obtained directly by the farmers in order to propose a tool with real data. Then, the goals of this work were: -

Determining an operational and based on real farm available data inventory to assess the water and carbon footprint at a farm-gate level. 30


-

Assessing if the carbon and water footprint individual analysis could provide enough information to producers in order to satisfy their agronomical and environmental necessities.

-

Making water and carbon water footprint methodologies more intelligible to the sector and based on more realistic data that represents specificity of each farm.

-

Obtaining a software tool to assess water and carbon footprints available for different crops.

2 Methods 2.1. Case Studies

A set of real farms will be used as pilot operational cases to test the operability & easiness of implementation of the proposed data mining&accounting procedures and the robustness of the calculations (conversion factors, indicators) and further environmental impact assessment. As a practical trial of assessment of sustainability and decision making our three case studies were carried out for three irrigated farms of grape, nectarine and corn grain (Table 1) located in the irrigated area around Lleida (region in NE of Spain, Ebro Basin). The three farms either comply with some quality standards (ex: GlobalGap, Nature choice) or their managers show genuine interest to make some kind of sustainability assessment of their fields and farms. Table 1.Key parameters of three crops. Category

Item

Unit

grape

nectarine

corn grain

Crop

Variety

-

Chardonnay

Sweet Beginner fruit

Cereal of Summer

Farm location

Lat (º)

41.7

41.5

41.7

Long (º)

0.48

0.46

0.78

Irrigation period

weeks

26

34

16

Yield

kg·ha-1·y-1

11,935

47,137

14,285

Soil

-1

Density of plantation

unit·ha

2,088

800

89,000

Surface (irrigation sector)

ha

4.2

12.5

24.5

Data of plantation

year

2004

2005

2005

First production after plantation

year

2nd

2nd (66%)

1st (annual)

Land Use

years

8

20

10

Previous crop before plantation

-

corn

barley

corn

Texture

-

loam

clayloam

siltyloam

2.2. System boundary

In the frame of Life cycle the assessment and in accordance with the ISO standards of water and carbon footprint, it is necessary to define the system boundary. It is important that the scope of reported emissions is both adequately comprehensive and consistent between different crops. The system boundary was defined from raw material extraction to farm gate. This implies to the scope from the pre-farm to farm-gate. Pre-farm processes (often referred to as ‗cradle‘) such as the extraction of raw materials, production, and transport of inputs used on the farm are also included 31


in the assessment. The production system (farm-gate) was structured in all the life cycle stages from cradle to gate (production of packaging and fertilizers, transport from the materials to the closest cooperatives, use, waste management, energy, auxiliary equipments). The results are expressed in the form of key life cycle stages as shown in Fig. 1. for each crop.

Cradle

Raw material Manufacture Electricity Diesel Transport Water

Fertilizers Pesticides

Packaging

Farm-gate

Wholesale

Transport

Cropproducti on

Fig 1. Cradle-to-farm-gate-to wholesale. Water and carbon footprintsare assessed using kg of commercial production as a functional unit for grapes, nectarines and corn grain at Ebro Basin (NE Spain). 2.3. Agronomic indices

Two indicators have been assessed in order to provide an agronomic assessment of water use WUE and EUE) by calculatingcrop evapotranspiration (ETc) and Effective Precipitation (Peff). To calculate ETc, Penman-Monteithformula has been applied. The method of Penman-Monteith is used to estimate the evapotranspiration of all crops (1). 𝐸𝑇𝑐 = 𝐾𝑐 · 𝐾𝑠 · 𝐸𝑇𝑜 (1) Where, ETcis the crop evapotranspiration [mm/day], Kc is the crop coefficient [-] obtained from FAOstat (ref), Ks is the stress factor [-] and ETo is the potential evapotranspiration [mm/day]. In order to assess effective precipitation (P eff), two considerations have been taken into account (2): 𝑖𝑓𝑃 > 6 − 8 𝑚𝑚𝑡𝑕𝑒𝑛, 𝑃𝐸𝑓𝑓 = 0.75 · 𝑃[mm] 𝑖𝑓𝑃 < 6 − 8 𝑚𝑚𝑡𝑕𝑒𝑛, 𝑃𝐸𝑓𝑓 = 0

[mm] (2)

Water Use Efficiency (WUE) and Energy Use Efficiency (EUE). The WUE [kg·m-3] is other indicator which refers to the ratio between yield and total water applied (3). 𝑊𝑈𝐸 =

𝑌 𝐼+𝑃 𝐸𝑓𝑓

[𝑘𝑔 · 𝑚−3 ] (3)

Where Y is the yield of the crop production, I is the irrigation and PEff is the Effective precipitation. The EUE [kg·kWh-1or L-1fuel] is the ratio between yield and energy consumption (4): EUE =

Y E

[kg · kWh−1 or L−1 fuel] (4)

Regarding the irrigation scheduling management several indicators have been taken into account: water application efficiency (WAE), leaching fraction (LF), accumulated net irrigation needed 32


(ANIN), accumulated gross irrigation needed (AGIN) and uniformity coefficient (UC). The irrigation system (sprinklers, drip irrigation and flood irrigation) defines the WAE and the UC which is the last uniformity coefficient measured at field (94% Excellent). The LF is the percentage of extra irrigation water needed for leaching irrigation water salts (5). 𝐿𝐹 =

𝐶𝐸𝑎 2·𝐶𝐸𝑚𝑎𝑥

[-] (5)

Where CEa[dS/m] is the Electrical Conductivity of irrigation and CE max is the Maximum Electrical Conductivity [dS/m]. Both irrigations needed, net (6) and gross (7), are accumulated during the irrigation campaign. 𝐴𝑁𝐼𝑁 = 𝐾𝑐 ·𝐸𝑇𝑜 − 𝑃𝐸𝑓𝑓 [mm] (6) 𝐴𝐺𝐼𝑁 =

𝐴𝑁𝐼𝑁 𝑊𝐴𝐸 (1−𝐿𝐹)

[mm] (7)

Deficit of irrigation is the difference between applied water and gross irrigation needed, meaning positive values the irrigation applied higher than gross irrigation water needed. Finally, environmental carbon assessment takes into account different stages from the crop‘s life cycle: production and application of raw materials, production and application of fertilizers and pesticides, energy consumption, fuel of transport and distribution and packaging.

2.4. Calculation of water footprint

The water footprint (WF) indicator is an accounting indicator of freshwater which neglects the availability of the resource and it provides no information on impact assessment.WF distinguishes the volumes of water consumed by different ‗water-colors‘ (green, blue and grey) depending on the type of water sourced and polluted. Water footprint of a primary crop is the volume of water used to grow it (the total rainwater evapotranspiration stored in the soil) at the place and during growth –green water-, plus the total volume of surface water or groundwater evapotranspiration during the growing period– blue water- and the theoretical volume required to dilute polluted water (generated during growth) to an ―unpolluted‖ condition –grey water- (Hoekstra et al. 2011). In this work, the total water footprint of the process of growing crops (WFproc) is the sum of the green and blue components being grey water left out of the scope(8): 𝑊𝐹𝑝𝑟𝑜𝑐 = 𝑊𝐹𝑝𝑟𝑜𝑐 ,𝑔𝑟𝑒𝑒𝑛 + 𝑊𝐹𝑝𝑟𝑜𝑐 ,𝑏𝑙𝑢𝑒 [m3 · tonne−1 ]

(8)

Water indices can be used as characterization factors for midpoint and endpoint impact assessment methods when applied to freshwater consumptive use. Water Stress Index (WSI) indicates the portion of consumptive water use that deprives other users of freshwater. The WSI has been used for the assessment of the environmental impact due to water consumption at a midpoint level considered in Life Cycle Impact Assessment, and it ranges from 0.01 to 1 (Pfister et al. 2009), with 1 meaning a serious water stress in a basin.Efoodprint tool provides the consumptive-based volumetric water footprint (green and blue) estimated using the water footprint manuals and the 33


stress-weighted water footprint developed by (Ridoutt and Pfister 2010) as water use impact using the WSI proposed by Pfister et al. (2009). The WSI is taken as a characterization factor for each watershed. However, due to a lack of standardized characterization factors to assess the green water footprint impact assessment, this work only focus on water footprint impact assessment for blue water (WFIAblue) following equation 9. 𝑊𝐹𝐼𝐴𝑏𝑙𝑢𝑒 = 𝑊𝐹𝑏𝑙𝑢𝑒 · 𝑊𝑆𝐼 [m3·tonne-1] (9) Where WFIAblue is the Water Footprint Impact Assessment[m3·tonne-1] by the Blue Water Footprint (WFblue) [m3·tonne-1] and WSI is the Water Stress Index [-] applied (Pfister et al. 2009) in the watershed where the crop is growing e.g. WSI=0.259 for Ebro basin.

2.5. Calculation of carbon footprint

The Carbon Footprint (CF) in accordance withISO 14040-44 and 14067(ISO/TC 2010)is a measure of the impact that human activities have on the environment in terms of the amount of Green House Gas (GHG) emitted over the full life cycle of a process or product measured in units of carbon dioxide (CO2). The climate or carbon footprint is expressed in CO2-eq. The CF value also depends on how the gas concentration decays over time in the atmosphere, and a time horizon of 100 years is commonly used in accordance with United Nations Framework Convention on Climate Change and the Kyoto Protocol (IPCC 2007). It is calculated as showed in equation 10. 𝐶𝐹 = 𝐸𝑉𝐶𝑂2 · 𝐼𝑛𝑝𝑢𝑡𝑓𝑙𝑜𝑤 [kgCO2,eq] (10)

Where CF is provided in units of kg CO2, eq, EV is the emission‘s vector per unit flow of mass[kg CO2, eq· process unit-1] and the input flows refer to the Life Cycle Inventory of crop‘s life cycle (e.g. unit of energy).

2.6.Software web Tool structure (efoodprint)

The efoodprint calculator assesses two parts: Part I: Water assessment and Part II: Carbon assessment. The tool is structured in five steps: 1.

Input data by the user (campaign data and water balance) regarding water and carbon qüestions.

2.

Database and default data.

3.

Total results and detailed results provided in 4 sections: I. Environmental Sustainability of Water Use, II. Agronomic Sustainability of water use, III. Irrigation Scheduling Management and IV. Environmental carbon assessment.

4.

Reports and recommendations.

34


5.

Tool appraisal: Users‘ opinions will be valuable given that the tool can be adapted to their needs.

3. Results and discussion Data collection from three farms located in Ebro basin for grape, nectarine and corn which were provided directly by the growers in face to face talks during campaign 2011.

3.1. Agronomic indices assessment

Concerning the WUE and EUE, the higher values are showed by nectarine since this farm had a higher production in 2011 by a) the irrigation water applied and b) energy consumption, respectively. Table 2. Water Indicators focus on agronomic sustainability of water use and irrigation scheduling management. units

Grape

nectarine

corn grain

Agronomic sustainability of water use WUE

kg yield/m3appliedwater

4.36

5.86

1.96

EUE

kg yield/kwhor l fuel consumed

4

14

5

Irrigation scheduling management WAE

-

0.80

0.80

0.65

LF

%

5

5

2

IWU

mm

214

512

465

AER

mm

70

222

55

ANIN

mm

214

411

439

AGIN

mm

280

539

692

DI

mm

-76

3

-17

Footnote: Water Use Efficiency (WUE), Energy Use Efficiency (EUE), Water Application Efficiency (WAE), Leaching Fraction (LF), Irrigation Water Use (IWU), Accumulated Effective Rainfall (AER), Accumulated Net Irrigation Needed (ANIN), Accumulated Gross Irrigation Needed (AGIN), Deficit of Irrigation (DI).

Figure 2 shows for each farm: grape (a and b), nectarine (c and d) and corn grain (e and f) the effective precipitation, the applied water and the gross water needs weekly for campaign 2011. Hence, we can foresee a priori in accordance with climatic parameters that in the area of study the best and worst suitable crops are nectarine and corn grain, respectively. These graphs may be very useful for the manager to identify where the irrigation practices (scheduling and amounts) can be tackled during the growing season to be more efficient.

35


Fig. 2Gross water needs (mm) vs applied water (mm) in grape (a), nectarine (c) and corn grain(e) and Accumulated Gross Water Needs (mm) vs applied water (mm) in grape (b), nectarine (d) and corn grain (f). 3.2. Water consumption assessment

Results of water indicators are shown in Table 2. Results from representative farms show that corn show high water footprint impact assessment (84.2 m3tonne-1) due to has higher value of BWF (325.2 m3tonne-1) for Ebro basin whereas that grape contributes with 46.4 m3·tonne-1 and nectarine 28.2 m3tonne-1 of WFIAblue. Regarding the GWF is higher also in corn farm (43.5 m3tonne-1) being 28.7 m3tonne-1 for grape and 19.2 m3tonne-1 for nectarine.

Table 2 Water Indicators focus on environmental sustainability of water use, agronomic sustainability of water use and irrigation scheduling management. units

grape

nectarine

corn grain

Environmental sustainability of water use BWF GWF WFIAblue

m3/tonne

179.1

108.7

325.2

3

28.7

19.2

43.5

3

46.4

28.2

84.2

m /tonne m /tonne

Footnote: Blue Water Footprint (BWF), Green Water Footprint (GWF), Water Footprint Impact Assessment (WFIA).

36


3.3. Carbon footprint assessment

Figure 3 shows the total impact assessment of carbon dioxide emissions and the contribution of the Global Warming Potential being the largest for fertilizer production and application in grape and corn crops and fuel for nectarine. The contribution of fertilizers use could be fairly well estimated based on the chemical consumption and the generally agreed-upon emission factors for chemicals production.

1,60E-01 1,40E-01

1,20E-01 1,00E-01 8,00E-02

6,00E-02

grape

4,00E-02

nectarine

2,00E-02

corn grain

0,00E+00

Fig. 3. Emissions of Global Warming Potential by crop production (kg CO2,eq·kg crop-1) for different parameters (fuel, transport,energy, fertilizer, phytosanitaries, packaging, infrastructure).

4 Conclusions General conclusions of this work have been: -

The research has provided a full inventory to assess the carbon and water footprint at farm level.

-

Achieving a whole environmental assessment of practices in farms, both assessments, carbon and water footprints are essentials in order to satisfy their agronomical and environmental necessities.

-

Becomes interesting to use real data from farms to provide the most accurate assessment since the results could be differed considerably with statistics data.

-

A developed software-web-based accounting and assessment module has been constructed, where the user will enter the field data (inventory), some conversion parameters will be entered, indicators will be calculated and an environmental impact assessment will be done.

The application of life cycle assessment indicators (carbon and water indices) enabled to take advantage of the benefits of each for suggesting environmental improvement in crop production. Through these midpoint indicators (Carbon and Water Footprint) have been possible to identify hotspots across and within the studied life cycle stages such as cultivation, transport and consumer use phase. The research identified that measures which address hotspots such as fertilization in crop production and fuel in transportation in field production is a priority to reduce greenhouse gas emissions. 37


This environmental calculator is a useful tool to evaluate the potential environmental impacts of crops in order to provide results for two main categories (water and carbon). The tool is designed for a mix of users to support decision making. Thisefoodprint tool adapts the requirements of data for the carbon and water footprint analysis to the reality of the farms. If too much data is required, then most of the values will be made up by the farmer instead of having real values. We can conclude that both, the stress-weighted WF and CF are useful indicators to assess the impact of farming systems on freshwater availability, tools which are increasingly recognized to address issues of environmental impacts and sustainability. Concerning the agronomic indices assessment we can conclude that nectarine is the crop which is better adapted in that zone regarding WUE and EUE results and climatic parameters. Assessing practical practices to reduce the environmental impact of irrigation (mainly, avoiding consumptions beyond real necessities and reducing the impact of leaching and erosion) will have to be done at a FMU scale and be integrated into the manager‘s dashboard. Therefore, the quantification of water use sustainability indicators should be based on a solid and simple conceptual model, so it can be integrated into the farmer‘s decision making processes.

Outlook: Methodological considerations for further research Generally, there are several criteria and methods to assess environmental at farm level, so it provides some increasing variability and uncertainty. Hence, it is needed assessing that from statistical point of view or from large regions. However, that issue lead us to: -

Discuss about underestimating or overvaluing the sustainability.

-

Quantify the uncertainty that these decisions could have to choose the correct criteria.

Acknowledgements It is a pleasure to thank the many who made this research possible: Project VALOR2010-00008 from the Catalan Government (Spain); Farmers for their help in providing data and their participation in this research.

References Alliance K (2012) Field to Market. http://www.fieldtomarket.org/fieldprint-calculator/. Accessed http://www.fieldtomarket.org/fieldprint-calculator/ BSI (2011) PAS 2050: Specification for the Assessment of the Life Cycle Greenhouse Gas Emissions of Goods and Services. Butchart SHM, Walpole M, Collen B, van Strien A, Scharlemann JPW, Almond REA, Baillie 38


JEM, Bomhard B, Brown C, Bruno J, Carpenter KE, Carr GM, Chanson J, Chenery AM, Csirke J, Davidson NC, Dentener F, Foster M, Galli A, Galloway JN, Genovesi P, Gregory RD, Hockings M, Kapos V, Lamarque J-F, Leverington F, Loh J, McGeoch MA, McRae L, Minasyan A, Hernández Morcillo M, Oldfield TEE, Pauly D, Quader S, Revenga C, Sauer JR, Skolnik B, Spear D, Stanwell-Smith D, Stuart SN, Symes A, Tierney M, Tyrrell TD, Vié J-C, Watson R (2010) Global Biodiversity: Indicators of Recent Declines. Science 328, 1164-1168. DOI: 10.1126/science.1187512. Ercin A, Aldaya M, Hoekstra A (2011) Corporate Water Footprint Accounting and Impact Assessment: The Case of the Water Footprint of a Sugar-Containing Carbonated Beverage. Water Resources Management 25 (2):721-741. doi:10.1007/s11269-010-9723-8 FAO FaAO (2003) World agriculture: towards 2015/2030. . In: Bruinsma J (ed) An FAO perspective Hoekstra A, Chapagain A, Mekonnen M (2005) Extended calculator of Water Footprint Network. http://www.waterfootprint.org/?page=cal/WaterFootprintCalculator. Hoekstra AY, Chapagain AK, Aldaya MM, Mekonnen MM (2009) Water Footprint Manual: State of the Art 2009. Water Footprint Network, Enschede,the Netherlands. Hoekstra AY, Chapagain AK, Aldaya MM, Mekonnen MM (2011) The Water Footprint AssessmentManual: Setting the Global Standard. Earthscan, London,UK. IPCC (2001) Climate change 2001: synthesis report. UK, Cambridge University Press ISO/TC SW (2010) Carbon footprint of products. Jefferies D, Muñoz I, Hodges J, King VJ, Aldaya M, Ercin AE, Milà i Canals L, Hoekstra AY (2012) Water Footprint and Life Cycle Assessment as approaches to assess potential impacts of products on water consumption. Key learning points from pilot studies on tea and margarine. Journal of Cleaner Production 33 (0):155-166. doi:10.1016/j.jclepro.2012.04.015 Mekonnen M, Hoekstra A (2011) The green, blue and grey water footprint of crops and derived crop products. Hydrology and Earth System Sciences 15(5):1577-1600 Mekonnen MM, Hoekstra AY (2010a) The Green, Blue and Grey Water Footprint of Crops and Derived Crop Products, Value of Water Research Report Series No.47. UNESCO-IHE, Delft, The Netherlands. www.waterfootprint.org/Reports/ Report47-WaterFootprintCrops-Vol1.pdf. Morrison J, Schulte P, Schenck R (2010) Corporate Water Accounting, Methods and Tools for Measuring Water Use and Its Impacts. . United Nations Environment Programme, United nations Global Compact, pacific Institute http:// wwwpacinstorg/reports/corporate_water_accounting_analysis/corporatewater_accounting_analysis pdf (accessed 101012) OECD (2001) Environmental indicators for agriculture. Paris, OECD. Pidd M Five simple principles of modelling. In: The 1996 Winter Simulation Conference, Coronado, California, USA, 1996. Ridoutt BG, Eady SJ, Sellahewa J, Simons L, Bektash R (2009) Water footprinting at the product brand level: case study and future challenges. Journal of Cleaner Production 17 (13):1228-1235. doi:10.1016/j.jclepro.2009.03.002 Ridoutt BG, Pfister S (2010) A revised approach to water footprinting to make transparent the 39


impacts of consumption and production on global freshwater scarcity. Global Environmental Change 20, 113-120. Smith P, Martino D, Cai Z, Gwary D, Janzen H, Kumar Pea (2007) Agriculture. In: Climate change 2007: Mitigation. Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Tubiello F, Soussana J-F, S.M H ( 2007) Crop and pasture response to climate change. Proc Natl Acad Sci USA 104:19686-19690 UNESCO-WWAP (2009) The United Nations World Water Development Report 3: Water in a Changing World. The United Nations Educational, Scientific and Cultural Organisation, Paris. Unilever (2010) Cool farm tool calculator. http://www.growingforthefuture.com/content/Cool+Farm+Tool. WRI (2012) GHG Protocol Agriculture Guidance. http://www.ghgprotocol.org/standards/agriculture-guidance.

40


Study of embodied energy and CO2eq.as ecoefficiency descriptors of Brazilian building materials Hawllynsgton G. FRANCO1 – Dimaghi SCHWAMBACK2 – Marcella R. M. SAADE3– Maristela G. SILVA2 – Vanessa GOMES3 1

Federal Universityof Espírito Santo, Av. Fernando Ferrari, 514 ,29075-910, Vitoria, Brazil

++55 27 4009 2652 [email protected] 2

Federal Universityof Espírito Santo, Av. Fernando Ferrari 514, 29075-910, Vitoria, Brazil

3

University of Campinas, Av. Albert Einstein 951, Campus Universitário Zeferino Vaz, 13083-970,

Campinas, Brazil

Abstract Purpose- This paper proposes to use LCA-based (embodied) energy and CO2eq., to assess ecoefficiency of building materials. Adequacy of using embodied CO2 or CO2eq., which includes all greenhouse gases emissions, is also investigated, as literature presents studies in both terms. Methods- Cradle to gate LCAs were performed using SimaPro 7.3 software. Data required for production cycle modeling of materials/components were mostly obtained from national literature or adapted from the SimaPro 7.3 built-in Ecoinvent database. Outputs were related to the material bill of four case studies to allow calculation and normalization of the analyzed indicators per unit of built area. Results- For the studied typology, results for embodied energy and embodied CO2eq.were, respectively, 1.139,96 MJ/m2 and 138,07 kg CO2eq./m2.The top six contributions (Portland cement CP III-32, ceramic brick, steel rebar, sawn timber planks, plywood and PVC tube) respond for over 80% of the total embodied energy. Analogously, over 80% embodied CO2eq.was related to cement, steel rebar, ceramic bricks and PVC tube. The CO 2 contribution to total CO2eq.emissions ranged from 52% (sawn timber plank) to 99% (Portland cement CP III-32). Conclusions-Ranking building materials based on embodied energy and CO 2eq.and its disclosure to designers can contribute to a more efficient selection of materials, enabling a more efficient, impact-based specifications and a balance of materials considering the lowest possible impact on the environment. Disclosure of impact profiles to the general public can also put societal pressure for mitigation and technological improvement in the related industries. Results confirmed that adopting embodied CO2 for all building materials and components, as a rule of thumb descriptor of climate change impact, can mislead conclusions. Calculation methods should therefore be made explicit, to avoid improper result interpretation by third-party users. For the studied building typology, a core database encompassing twelve building materials and components provides a 41


very accurate description of the embodied energy and CO2eq.profiles altogether, which can possibly streamline indicators monitoring scope. Identification of key materials which effectively define their impact profile have important implications not only on research time and investment, but also on understanding by designers and successful implementation of such concepts in their daily specification practice. Key words: embodied energy; embodied CO2, embodied CO2eq., Lifecycle assessment; building material; indicators; eco-efficiency

Introduction The building sector is responsible for major impacts on the environment. On a global scale, building material manufacture and transportation as well as installation and construction of buildings consume great quantities of energy and emitting large amounts of greenhouse gases, GHG (DIMOUDI; TOMPA, 2008). The carbon footprint (or embodied CO2) and embodied energy are indicators that can measure, respectively, the CO2 emission and the energy used during the manufacture of building materials and components, in transporting these to the site, and during the construction process itself. They can further include the measurement of energy and CO2 emission that may be incurred during renovations and replacement of components and those resulting form demolition, waste and reprocessing at the end of the building service life. Conceptual definition of this indicator and related accounting varies worldwide. Wiedmann and Minx (2008) defend that the carbon footprint should measure the amount of carbon dioxide emissions directly or indirectly caused by human activities or accumulated throughout a product‘s life cycle. On the other hand, Post (2006) states that the indicator should represent the total amount of all greenhouse gases emitted during a product or process‘ life cycle. Such a discrepancy between definitions reveals that the calculation methodology varies, and that results from different authors may lead to mistaken interpretations. Both indicators can be obtained from LCA platforms or databases such as the Inventory of Carbon & Energy, compiled and written by Hammond and Jones (2011) and a report written by Alcorn (2003). In Brazil, studies performed by Saade et al. (2012) and Manfredini and Sattler (2005) emphasize the necessity of developing life cycle inventories for Brazilian construction materials. This paper proposes indicators of life cycle embodied energy and embodied CO2eq., normalized per unit of built area (m²), as part of a set of indicators to assess the material eco-efficiency of buildings. Implications of considering embodied CO2 and embodied CO2eq. are also discussed. The study presented here is part of the Green Building R&D project funded by CPFL/ANEEL.

Methodology The performed cradle-to-gate LCAs followed ISO 14040:2006 methodological guidelines and were supported by SimaPro 7.3 software. The necessary data for modeling the production cycle of materials and components were mostly taken from national literature or adapted from the 42


SimaPro7.3 built-in Ecoinvent database by switching into the Brazilian energy mix. Table 1 indicates the functional unit adopted for each material/component, and the data sources used for modeling the respective production processes. To assess the influence of the other greenhouse gases on final results, both embodied CO 2 and embodied CO2eq. were calculated. Obtaining of embodied CO2eq.figures was assisted by CML 2001 v.2.05 environmental impact analysis which presents equivalency factors for all greenhouse gases in the global warming impact category, and expresses results in kg of CO 2eq. per functional unit. The embodied CO2 and embodied CO2eq. per functional unit were calculated from the inventory analysis for each material/component, except for the ceramic brick value, which was obtained from University of Bath‘s inventory of carbon and energy (HAMMOND; JONES, 2011). Though these authors used an electricity grid that differs from the Brazilian energy mix, and such a difference can imply in less accurate results, the methodological thoroughness observed in their research suggest its use as a potential proxy, given the lack of data related to that specific component in national and international LCI databases.The embodied energy indicator (EE) was calculated using the LCI provided by the support platform used, except for the ceramic brick value, which was obtained from Manfredini and Sattler (2005), whose adopted methodological approach was explicit and seemed reasonably close to the one herein proposed. Studied typology is basically low-rise (up to 3 floors), low window-to-wall ratio, reinforced concrete-framed, masonry façade and partitions, and ceramic or metallic roofing buildings. The four cases comprise one integrated service center (4.975,55 m²); one police-training center (1.511,74 m²); and two school buildings (4.869,23 m² and 2963,08 m²). Total usage of material/components was quantified for all case studies - according to the functional unit previously defined, divided by the total built area and corrected by national estimates for construction waste (Agopyan et al, 1998). Portland cement and ready-mixed concrete are here expressed considering three amounts of ground granulated blast furnace slag (ggbs) as clinker replacement (5% in CPI-32, 30% in CPII-E-32, and 66% in CPIII32, consistent with Brazilian standards NBR 5732:1991, NBR 11578:1991, and NBR 5735:1991). In all cases, ready-mixed concrete, steel rebar and formwork were considered only for the superstructure to isolate the effects of the soil‘s carrying capacity on the sizing - and consequently on material consumption - of foundation elements. External and urbanization elements were also disregarded. To consider typical reusability, consumption of plywood, sawn planks and raw timber was divided by a factor of four. Consumption of each material/component per unit of built area was then multiplied by its embodied energy/CO2/CO2eq.per functional unit, in order to obtain these metrics per m².

Results and Discussion For the studied typology, results for embodied energy and embodied CO 2eq.were, respectively, 1.139,96 MJ/m2 and 138,07 kg CO2eq./m2. Fay et al. (2000) speculated that 30 MPa ready-mixed concrete, steel rebar, cement, ceramic brick and timber are the materials with most embodied energy per square meter of built area. Asif et al. (2007) added glass and aluminum to this list. Saade et al. (2012);Gheewala and Kofoworola(2009) 43


also highlighted the relevance of concrete, Portland cement and reinforcement steel on the overall energy embodied in building materials. Results achieved in this research corroborate literature data and also show Portland cement and concrete (considered as component delivered to site) as the main contributors to the building‘s embodied energy profile. It is noteworthy that international studies usually investigate the performance of ordinary Portland cement, which is composed primarily by clinker, with little or no mineral admixtures and would be equivalent to Brazilian CP I-S-32. In Brazil, however, CP II-E32 (30% of ground granulated blast furnace slag, ggbs) is most widely commercially available, while CP III-32 (66% of ggbs) is the top selling cement in the geographic region of all of the cases studied. Figure 1 presents the median values of embodied energy of building materials and components per m² of built area. As explained, embodied energy and CO 2/CO2eq.of Portland cement and concrete are expressed in terms of three amounts of ggbs used as a clinker replacement, consistent with Brazilian standards NBR 5732:1991, NBR 11578:1991 and NBR 5735:1991. Portland cement indicated in Figure 1 was used in the production of other cement-based elements, as concrete was delivered ready mixed.

Figure 1 Embodied energy of materials and components per built m² (median, MJ/m²) In the scenario shown in Figure 2, concrete was broken down into its elements, which were added to cement, sand and gravel used in other construction applications.

Figure 2 Embodied energy of materials and components per built m², with concrete broken down into its constituents, which were added to cement, sand and gravel used in other applications (median, MJ/m²)

Table 1 presents embodied CO2eq., embodied CO2 and embodied energy values for the three types of cement with ggbs as clinker replacement compatible with Brazilian standards, as well as the corresponding concrete mixes. Both indicators for cement (and, therefore, for the corresponding concrete) diminished considerably as the ggbs content increased from 5% (CP I-S-32) to 30% (CP II-E-32) and 66% (CP III-32). Nevertheless, the highest embodied CO2eq.was still that of cement CP III-E-32, followed by steel rebar and ceramic brick. Powell and Monahan (2011) and Yan et al (2000) also reported large contributions from ready-mixed concrete and steel rebar.

¹ Concrete mixes containing three amounts of ground granulated blast furnace slag (ggbs) as clinker replacement in cement production (CP I-S-32 – 5%; CP II-E-32 – 30%; CP III-32 – 66%) were calculated for illustration. All case studies used cement type CPIII-32.

44


Table 1 Embodied CO2eq., CO2 and energy per built m² for the cement with ggbs and respective concrete mixes

Table 2 shows data of the building materials/components actually applied in the case studies. Application of straightforward Pareto ranking suggests that, for the studied building typology, the top six contributions (Portland cement CP III-32, ceramic brick, steel rebar, sawn timber planks, plywood and PVC tube) respond for over 82,85% of the total embodied energy. Analogously, over 81,33% of the embodied CO2eq.was related to cement, steel rebar, ceramic bricks and PVC tube. Table 2 Embodied CO2eq., CO2 and energy per built m² for all building materials/components analyzed in the case studies Figure 3 shows the median values of CO2eq.embodied in materials and components per m2 of built area, with concrete broken down into its elements, which were added to cement, sand and gravel used in other construction applications. The same procedure was applied for embodied CO 2.

Figure 3 Embodied CO2eq. in materials and components per built m² (median, kg CO2eq./m²)

Figure 4 Embodied CO2 in materials and components per built m² (median, kg CO 2/m²) Literature screening confirmed that results are equally presented in terms of embodied CO 2, for the sake of simplicity and communication leveling, and of embodied CO 2eq., which includes all GHG emissions as a more complete impact metric in terms of climate change. Contrasting of embodied CO2 and embodied CO2eq.results (Table 2) shows considerable change in the indicators absolute values with the inclusion of the other GHG emissions in the calculation. This emphasizes the need of making calculation methods explicit, to avoid improper result interpretation and disclosure. The CO2 contribution to total CO2eq.emissions ranged from 52% (sawn timber plank) to 99% (Portland cement CP III-32). For cement, ceramic brick and PVC conduit, CO2 emission represents over 95% or all GHG emissions. However, two other major situations - and corresponding groupings of materials/components - in terms of embodied CO2 and CO2eq.became very clear: 

CO2 proportion in GHG emissions is above 80% (between 80%-83%), e.g. ceramic tile (ranked #8), sawn roundwood (#12), copper wire (#13), sawn wood plank (#11), plywood (#9) and acrylic paint (#10); which might be considered enough to be a reasonable GHG descriptor for specific applications or preliminary screening; and



CO2 proportion in GHG emissions is below 80% (between 52% and 79%), e.g. steel rebar (#2), hydrated lime (#7), PVC tube (#4) and roof steel structure (#6), for which contribution of other greenhouse gases is unequivocally significant and cannot be neglected.

These results confirm that adopting embodied CO2, for all building materials and components, as a rule of thumb descriptor of climate change impact can clearly mislead conclusions. 45


Finally, a core database - encompassing cement, steel rebar, ceramic brick, PVC (tube and conduit), roof steel structure, hydrated lime, ceramic tile, plywood, acrylic paint, sawn timber plank and sawn roundwood -provides a very accurate description of the embodied energy and CO2eq.profiles altogether, which can possibly streamline indicators monitoring scope.

Final remarks Ranking building materials based on embodied energy and CO 2eq.and its disclosure to designers can contribute to a more efficient selection of materials, enabling a more efficient, impact-based specifications and a balance of materials considering the lowest possible impact on the environment. Disclosure of impact profiles to the general public can also put societal pressure for mitigation and technological improvement in the related industries. According with literature, there are significant disagreements in terms of carbon footprint definition. Those differences can imply in mistaken interpretations and disclosure. Comparison between results of embodied CO2 and embodied CO2eq.achieved in this study shows that the use of different methodologies lead to, in some cases, important variation in absolute values, and that adopting embodied CO2 as a rule of thumb descriptor of climate change impact for all building materials and components clearly mislead conclusions. Also, for the studied building typology, a core database encompassing twelve materials and components provides a very accurate description of the embodied energy and CO 2eq.profiles altogether, which can possibly streamline indicators monitoring scope. Identification of key materials which effectively define their impact profile have important implications not only on research time and investment, but also on understanding by designers and successful implementation of such concepts in their daily specification practice. Results shown in this paper are specific to the construction typology considered, basically low rise, low window-to-wall ratio, reinforced concrete-framed, masonry façade and partitions, and ceramic or metallic roofing. The case studies represent typical local building construction practices, not only for low-rise buildings but also for prevalent high-rise apartment buildings. Analysis of other construction typologies (e.g. steel or wood-framed, different wall systems and window-to-wall ratio), standards and cultures may result in other rankings and contributions per material/component. Next research steps include investigation of additional building materials, components and systems, and of their performance as measured by other indicators; database expansion to include other building typologies; and comparison of embodied and operational energy in Brazilian buildings given the differences in industry technology and energy mix in relation to international data. It is also expected that, following a coordinated methodological outline, future works evolve to gradually constitute an LCI database of the most relevant building materials and components, to enable the use of the proposed metrics, as well as LCA methodology as a whole, as decisionmaking tools.

46


References Agopyan, V. et al. (1998). Alternativas para a redução do desperdício de materiais nos canteiros de obras. São Paulo. Alcorn, A. (2003) Embodied energy and CO 2 coefficients for New Zealand building materials. http://www.victoria.ac.nz/cbpr/documents/pdfs/ee-co2_report_2003.pdf. Accessed 12 april 2012 Asif M, Muneer T, Kelley R (2007) Life cycle assessment: A case study of a dwelling home in Scotland. BuildingandEnvironment, 42: 1391-1394. doi: 10.1016/j.buildenv.2005.11.023 Associação Brasileira de Normas Técnicas NBR 11578 (1991) Cimento Portland Composto Associação Brasileira de Normas Técnicas NBR 5732 (1991) Cimento Portland Comum Associação Brasileira de Normas Técnicas NBR 5735 (1991) Cimento Portland de Alto Forno Dimoudi A, Tompa C. (2008) Energy and environmental indicators related to construction of office buildings. Resources, Conservation and Recycling; 53(1–2): 86–95 .doi:10.1016/j.resconrec.2008.09.008 Fay R, Treloar G, Iyer-raniga U (2000) Life-cycle energy analysis of buildings: a case study. Building Research & Information 28: 31–41 Gheewala H and Kofoworola F (2009) Life cycle energy assessment of a typical office building in Thailand. Building and Environment 41: 1076–1083. doi:10.1016/j.enbuild.2009.06.002 Hammond G, Jones C (2011) Inventory of Carbon and Energy (ICE), Carbon Vision Buildings Program, University of Bath, United Kingdom. Manfredini C, Sattler M (2005) Estimativa da energia incorporada a materiais de cerâmica vermelha no Rio Grande do Sul. AmbienteConstruído 5: 23-37 Powell J and Monahan J (2011) An embodied carbon and energy analysis of modern methods of construction in housing: A case study using a lifecycle assessment framework. Energy and Building 43:179-188. doi:10.1016/j.enbuild.2010.09.005 Saade M R M, Silva M G, Gomes V, Franco H G, Schwamback D, Lavor B (2012) Proposition and preliminary analysis of a core set of indicators to describe material eco-efficiency of Brazilian buildings. In: Smart and Sustainable Built Environment2012, São Paulo. Proceedings, São Paulo, p.525-532 Wiedmann T, Minx J (2008) A Definition of 'Carbon Footprint'. In: Pertsova, C.C. (ed.), Ecological Economics Research Trends. Hauppauge NY, USA, p. 1-11. Yan H, Shen Q, Fan L C H, Wang Y, Zhang L (2010) Greenhouse gas emissions in building construction: A case study of One Peking in Hong Kong. Building And Environment 45: 949-955. doi:10.1016/j.buildenv.2009.09.014 Post (2006) Carbon footprint of electricity generation. accessed 23 May 2012

47


Charts Table 1 Buildingmaterialsandcomponents Ready-mixed Concrete (fck 30)¹ Portland Cement (CP I-S-32, CPII-E-32 and CPIII-32)¹ Steel rebar, Roofing steel structure, Copper wire PVC (conduit, tube) Wood (plywood; dry plank; dry roundwood) Sand, Gravel, Acrylic paint, Hydrated lime, Adhesive mortar, Ceramic tile

Functional Unit 1 m³ 1ton

Datasource Silva, 2006 Silva, 2006

1ton

ELCD, version 2.0

1ton 1 m³

Industry Data, version2.0 Ecoinvent, version 2.2

1ton

Ecoinvent, version 2.2

¹ Concrete mixes containing three amounts of ground granulated blast furnace slag (ggbs) as clinker replacement in cement production (CP I-S-32 – 5%; CP II-E-32 – 30%; CP III-32 – 66%) were calculated for illustration. All case studies used cement type CPIII-32. Table 2 Embodied CO2 (kg CO2/m²)

Materials/components

Portland cement

Ready-mixed concrete

Embodied CO2eq. (kg CO2eq./m²) 89,42

Embodied Energy (MJ/m²)

CP I-S-32

88,68

CP II-E-32

64,79

65,33

430,59

CP III-32

37,93

38,35

254,37

CP I-S-32

38,91

39,49

256,68

CP II-E-32

31,83

32,38

210,55

CP III-32

15,31

19,28

124,89

587,93

Table 3 Embodied CO2 (kg CO2/m²)

Materials/components

Embodied CO2eq. (kg CO2eq./m²) 38,35


CP III-32

37,93

CP III-32

15,31

19,28

124,89

Steel rebar

20,45

25,82

135,78

Ceramicbrick

Portland cement Ready-mixed concrete

254,37

14,70

15,33

161,24

PVC tube

5,59

9,29

61,54

PVC Conduit

4,87

5,11

34,63

Roofsteelstructure

4,30

7,16

52,67

Hydrated lime

4,01

5,34

47,41

Ceramic tile

2,73

3,28

86,25

Plywood

2,30 1,03

1,58

Acrylicpaint

1,85 0,82

132,91

Sawntimber (planks)

0,58

1,13

1,24 48


Sawnroundwood

0,26

0,32

56,76

Copperwire

0,08

0,10

1,15

Sand

0,00

0,00

0,01

Gravel

0,00

0,00

0,02

400,00

CP II-E-32

CP III-32

300,00 200,00 100,00

1000,00 Embodied Energy (MJ/m²)

CP I-S-32 500,00

CP III-32 600,00 400,00 200,00

100,00 80,00 60,00 40,00 20,00 0,00

Fig 3

Fig 2

CP I-S-32 CP II-E-32 CP III-32

Embodied CO2eq. (kg CO2eq./m²)

120,00

CP II-E-32

800,00

Fig 1 140,00

CP I-S-32

0,00

0,00

Embodied CO2 (kg CO2/m²)


600,00

150,00

CP I-S-32

CP II-E-32

120,00

CP III-32

90,00 60,00 30,00 0,00

Fig 4

49


Modeling carbon footprint of the Chilean apple production Alfredo Iriarte1,2,*, Pablo Villalobos3, Pablo Yañez3, Carlos Huenchuleo3 1

Department of Industrial Management and Modelling. Faculty of Engineering. Universidad de Talca. Casilla

747, Talca, Chile. 2

Chilean Food Processing Research Centre (Centro de Estudios en AlimentosProcesados CEAP). R09I2001.

Av. San Miguel km 2. Talca, Chile. 3

Department of Agricultural Economics.Faculty of Agricultural Sciences. Universidad de Talca. Casilla 747,

Talca, Chile. *

Corresponding author. Tel.: ++56 75 2017 00; fax: þ56 75 32 59 58.E-mail: [email protected]

http://ing.utalca.cl

Abstract Purpose. The main objective of this study is to evaluate, using a life–cycle approach, the carbon footprint of the intensive apple orchard system in Chile. Additional objective is to identify the factors that contributed significantly to the greenhouse gas emissions of this agricultural system Methods. The method used in this study is according to the ISO 14040 framework and the main recommendations in the Publicly Available Specification (PAS) 2050. The system boundaries included all the life cycle stages from the cradle to the farm gate (harvested apples), consistent with the business-to-business approach indicated in PAS 2050. The apple production analyzed in this study corresponds to nationwide representative practices. Results and Conclusions.The results indicate that carbon footprint of the Chilean apple orchard production, under typical agricultural conditions, is 0.045 kg CO 2 equiv./kg apple. The mineral fertilizers (which include their field emissions) is the agricultural factor that presents the highest contribution (49%) to carbon footprint of the apple production. In contrast, packaging waste has a minimum contribution; this factor contributes less than 5% to the greenhouse gas (GHG) emissions. The application of the life–cycle approach helped to identify improvement measures to reduce GHG emissions of the orchard production system. Key words: apple production, greenhouse gas emissions, mineral fertilizers carbon footprint, Chile

1

Introduction

Chile is a major off-season fruit supplier and covers a significant portion of fresh fruit imports made by the United States, the European Union and Japan. Chile is the largest southern hemisphere producer and exporter of apple (Centro de Competividad del Maule 2000). Estimating carbon footprint of agricultural systems is becoming an important issue for country‘s horticulture 50


sector. The term ―carbon footprint‖ stands for the total sum of all greenhouse gas emissions caused by a product‘s life cycle. Growers in Chile need to measure the carbon footprints of their products, allowing them to satisfy consumer demand for the information and improve their production processes. This study presents the results of the estimation of the carbon footprint ofChilean apple under intensive orchard production.

2

Methodology

2.1 Goal, scope, and functional unit

The main objective of this study is to evaluate, using a life–cycle approach, the carbon footprint of the intensive apple orchard system in Chile. Additional objective is to identify the agricultural factors that contributed significantly to the greenhouse gas emissions of this system. The study area corresponds to the region of Maule; the main apple production zone of Chile. This region produces an average of 62% of the apple of the country. The study is according to the ISO 14040 framework (ISO 2006) and the main recommendations of the Publicly Available Specification (PAS) 2050 (BSI 2008). The functional unit is the production of 1 kg of apples under intensive practice in Chile. 2.2 System boundaries

The study is a cradle-to-farm gate LCA. The system includes all the agricultural stages up to obtaining the apples in the orchard. The agricultural factors evaluated in the system are: (1) fertilizers, (2) pesticides, (3) electricity consumption, (4) waste of apple production and (5) diesel consumption for agricultural operations and for application of agrochemicals. 2.3 Data on agricultural inputs

For foreground system, primary data are used to carry out this study. The primary data are collected directly from local grower though interviews, questionnaires and on-site measuring. The agricultural inputs collected in the study correspond to representative practices used in Chile. For background system, secondary data (e.g. manufacture of fertilizers and pesticides) are obtained from ecoinvent database (Frischknecht and Rebitzer 2005), with Chilean electricity production mix incorporated to reflect local conditions. 2.4 Emissions of nitrous oxidefrom application of fertilizers and evaluation of land use change

One of the major concerns in the net balance of greenhouse gas emissions of agricultural products is the nitrous oxide (N2O) emissions produced during and after growth of the crops. In this study, the N2O emissions from the application of fertilizers are estimated based on default emission factor from IPCC guidelines (IPCC 2006). 51


In relation to the land use change (LUC), according to the PAS 2050 (BSI 2008), LUC from less than 20 years are taken in to account. In our case, the orchard under study date back from more than 20 years. 2.5 Method for assessing GHG emissions

The CCaLC carbon footprinting software program (CCaLC 2012) has been used to model the apple orchard system and to evaluate the GHG emissions. For GHG emissions, this program uses the methodology defined by PAS 2050 (BSI 2008).

3 Results The results indicate that carbon footprint of the Chilean apple orchard production, under typical agricultural conditions, is 0.045 kg CO 2 equiv./kg apple. The results are in agreement with those obtained in commercial orchards in New Zealand by Milài Canals et al. (2006). The mineral fertilizers (which include their field emissions of N 2O) is the agricultural factor that presents the highest contribution (49%) to carbon footprint of the apple production (see figure 2). The waste of apple production has a minimum contribution; this factor contributes less than 5% to the GHG emissions.

Figure 1 Contribution of the agricultural activities to GHG emissions of the apple orchard production in Chile

4 Conclusions It was found that, in Chilean conditions, the carbon footprint of apple production is 0.045 kg CO2 equiv./kg apple. The mineral fertilizers contribute significantly to GHG emissions in the apple 52


orchard system. In order to identify measures for reducing the carbon footprint for Chilean apple production, other sources of fertilizers should be environmentally evaluated, such as organic fertilizers (e.g. local livestock manure) and field emissions of N 2O should be reduced.

Acknowledgements The present study was supported by the Chilean Food Processing Research Center (Centro de Estudios en AlimentosProcesados CEAP), R09I2001 and by the Project I001952.

References BSI (British Standards Institution) (2008) PAS 2050Specification for the assessment of thelife cycle greenhouse gas emissions of goods and services.London, UK. Centro de Competividad del Maule (2000). Manzanos. Universidad de Talca. Talca, Chile CCaLC(2012) Carbon Calculations over the Life Cycle ofIndustrial Activities.The University of Manchester, UK http://www.ccalc.org.uk/software.php Frischknecht R,Rebitzer G (2005) The ecoinvent database system: a comprehensive webbasedLCA database. J Clean Prod 13:1337-43 IPCC (Intergovernmental Panel on Climate Change) (2006) N2O emissions frommanaged soils, and CO2 emissions from lime and urea application[chapter 11].In:Eggleston HS, Buendia L, Miwa K, Ngara T, Tanabe K, editors. IPCC guidelinesfor national greenhouse gas inventories, vol. 4. Hayama, Japan ISO (International Organization of Standardization) (2006) ISO 14040Environmentalmanagement - Life cycle assessment - Principles and framework. Geneva, Switzerland

53


Carbon Footprint of Three Walls Systems in Low Cost Housing in Colima, Mexico Víctor Alberto Arvizu Piña1-Gabriel Gómez Azpeitia1-Pablo Arena Granados2 1

Facultad de Arquitectura y Diseño, Universidad de Colima, Km. 9 carretera Colima-Coquimatlán, México,

C.P. 28400 2

Universidad Tecnológica Nacional, Facultad Regional Mendoza, Argentina

1

[email protected], [email protected]

2

[email protected]

Introduction Along the Mexican territory you can find a wide variety of climates covering cold, warm and temperate regions, however, low cost housing does not considers as part of its design process, aspects necessary to enable an adaptation to these different conditions. The use of the cheapest materials and not necessarily the best suited to the climatic conditions of each site, is a common denominator that can be seen in this type of housing. This not only results in an economic impact generated by high energy consumption to achieve thermal comfort inside these houses, but also produce different types of environmental impacts through the generation of solid, liquid and gas emissions, which are generally not regulated by the competent authorities. Some of these impacts are related to the problem of Global Warming, and specifically with the Greenhouse Gases issue, CO2 being one of the most important in this matter. In order to contribute to the generation of knowledge on environmental matter in the field of construction of massive housing, the National Housing Commission (a Mexican institution) has funded this work as part of the Life Cycle Analysis of Affordable Housing in Mexico. Case Study: The Walls Construction Systems in the city of Colima, Mexico. This study's main objective is to dimension and asses the Carbon Footprint of the entire life cycle of the main wall construction systems used in low cost housing in Mexico. The main purpose comes with the aim of establishing a series of recommendations to the principal players in the field of design and construction of such housing.

Methodology The methodological process adhered to the already established on standard series ISO 14040 (2006) and 14044 (2006), studies concerning Life Cycle Analysis. For input and output inventories took into account the Ecoinvent database (v1 and 2), however, since the building systems analyzed 54


correspond to processes which mostly considered semi-industrial or purely craft, part of the information did not adhere to the established in this database, so additionally it was collected through field work, laboratory testing and through literature. Specialized software SimaPro 7.1 was used as support in the assessment of environmental impacts, specifically to determine the carbon footprint of each building system analyzed. System Limits As the most common materials for building walls in low cost housing in Colima, Mexico, the following building systems were chosen:

Traditional brick of burned clay. Is handmade with soil and water. The brick consistency is achieved by baking it in ovens made it from the same bricks and where wood and coconut husk are used as fuel. Its dimensions are 5x14x28cm and weighs 2.837kg (Fig1). Solid cement brick. It consists of a mixture of cement, sand, water and jal 1. Its dimensions are 10x14x28cm and weighs 5.12kg (Fig 2).

Cement Hollow Block. It is a piece composed of cement, sand and water. Its dimensions are 15x20x40cm and weighs 8.624kg (Fig 3).

Fig 1 Traditional brick of burned clay

Fig 2 Solid cementbrick

Fig Cementholow block

3

Soruce: field work

In addition to the aforementioned pieces, it is also considered in the analysis mortar of cementsand for bonding of masonry pieces and for the surface covering that consolidates the structural confining of the masonry, and the vertical structural reinforcement in all cases based on steelreinforced concrete (varies in quantity and type of steel). In the case of hollow cement block, it was also considered a steel horizontal reinforcement, typical of this building system, which is placed every 40 cm. The energy from the human being is not considered for any of the cases.

The phases of material-extraction, transport to the production site, manufacturing, transport to the construction place, building, occupation, demolition and transport to the trash site were considered. It was not considered to reuse the waste at the end of the life cycle. The measure unit that serves as parameter to analyze the three systems is the square meter (m 2) of 1

Lightweight porous mineral commonly extracted from the region of Jalisco, Mexico. 55


wall. However, in the final presentation of the results and life cycle interpretation, the surface vegetation needed is used to offset the carbon footprint generated by each of the building systems. The impact category considered was the Global Warming through CO 2 equivalent emissions.

Material and Energy Consumption Figure 4 shows the general diagram of the relationship between energy consumption and materials directly involved in each stage of the Life Cycle of the building systems analyzed. Inventories 1, 2 and 3 correspond to the extraction in open pit mines of sand, gravel and jal, used as raw material in the production and the construction phases. Since they are local materials, they are not includes in international inventories as Ecoinvent and similar. Therefore, its corresponding data were collected in field visits.

Inventories 4, 5 and 7 correspond to the generation of cement and steel, as well as the use of different equipment whose operation is based on hydrocarbons (mostly transportation). Due to industrialization and generalization of these processes worldwide, the information has been taken from the Ecoinvent database, that best conforms to the local reality.

Inventory 6, corresponding to the consumption of electricity, was based in the energy mix in Mexico, generated between 2004 and 2007 from different plants installed in the country. 62% comes from thermal power plants (based on steam generated from the combustion of fuel oil, gas and diesel), 16% hydroelectric plants, 12% coal-fired power plants, and 4% from geothermal plants (Federal Commission of Electricity, 2009).

Because the energy used for cooking traditional bricks during production comes from the combustion of wood and a waste of the coconut plant, known as "oakum" (abundant in the region of Colima), the information of its heat capacity is not included in the Ecoinvent database, so the corresponding data were based on the values of energy capacity of wood, reported by Becker (1985), and for coconut waste reported by Donaciano (2007). However, the emissions to the atmosphere associated to its combustion were obtained from a laboratory test called carbonization test, which obtains specifically the CO2 emissions.

From the mentioned inventories, these were developed for all the stages of the life cycle of each wall system analyzed. As specified in Figure 4, inventory 10 corresponds to the raw materials extraction, transport to the site of production, materials elaboration and transport to the construction site.

56


Fig 4 General outline of inflows inventories (material and energy)

Soruce: field work

Inventory 11 corresponds to the stage of construction of the wall, while inventory 12 to the occupation of the house. In this phase it is considered the electrical energy needed to maintain the internal temperature below 28 ° C2 for 50 years3. TRNSyS software was used for three thermal simulations of anlow cost housing, where the only change was the wall construction system. Inventory 13 corresponds to the phase of demolition of the wall and its transportation to the final disposal site.

Results Since the environmental impact category was established as Global Warming as part of this research, we used the methodology of the IPCC 2001 GWP 100th V1.03. In the three building 2

Maximum comfort limit of temperature in Colima, Mexico Established period of time for Life Cycle phase of housing

3

57


systems analyzed, the housing occupancy stage is the one that generates the most carbon footprint, accounting for over 99% of the total. It is important to have in consideration that at this stage there is not involve any material consumption, but energy wise electricity is used to maintain thermal comfort inside the home for 50 years. In this matter, and only comparing this phase, the construction system based on hollow cement block is the largest CO2 emissions, while the solid cement brick represents 83.41% compared to the hollow block, and the brick and clay the 84.33%. On the other hand, analyzing the rest of the life cycle, the hollow block remains the highest carbon footprint, however, the clay brick is now the lowest with 79.6%, while the solid cement brick comes in second with 88.7% (Fig 5).

Comparative Percent Carbon Footprint

Fig 5 Comparative analysis of CO 2 emissions 100,00%

100,00% 100,00%

90,00%

88,70% 83,41%

80,00%

84,33% 79,60%

70,00% 60,00% 50,00% 40,00% 30,00% 20,00% 10,00% 0,00% Holow cement block

Solid cement brick Traditional brick of burned clay Wall system

Use phase

Rest of the Life Cycle

Regardless of the house occupation phase, the construction stage is the largest contributor to the carbon footprint in the three building systems, as it is over 60% from the rest of the phases. In this matter it is important to highlight the brick, which contributes 75.17%, while the hollow block and solid cement brick with 61.24% and 53.57% respectively. Next in importance, the first four phases of the life cycle, from raw material extraction, transportation to the site of production, processing and transport parts to the construction site of the wall. In this case, the solid cement brick is the one with the most impact; it contributes with 41.93%, followed by the hollow block with 35.04% and 19.17% the clay brick. The stages of demolition and transportation to the place of waste disposal contribute less than 6% in each case (Fig 6).

58


Fig 6 Comparative analysis of the carbon footprint without consider the occupation phase

Carbon footprint percent

100,00%

3,71%

5,66%

4,50%

90,00% 80,00% 70,00% 60,00%

53,57%

61,24%

75,29%

50,00% 40,00%

Construction

30,00% 20,00% 10,00%

Demolition-Transport

41,93%

35,04%

19,04%

0,00% Holow cement Solid cement block brick

Extraction-TransportProduction-Transport

Traditional brick of burned clay

Wall system Due to the nature of the construction processes for the three materials, cement and steel are a fundamental part of their placing. It is for these components to the construction stage are the most important environmental issues in these three cases. Particularly cement contributes to the most carbon footprint, as well as mortar used in binding and coating parts of the wall, also used for making the hollow block and solid cement brick. In the case of the clay brick, its contribution is due to the amount required to join the pieces, as being the smallest of the three, a major amount required per square meter of wall. It also emphasizes the impact of steel in hollow block, contributing to 34.5% of its total. This is because of the use rods of 3/8 "as vertical reinforcement, also requires horizontal steel reinforcement each 40 cm, resulting in practically doubling steel with comparison to the two other building systems (Fig7).

Fig 7 Carbon footprint comparative analysis (inflows materials)

Carbon footprint percent

100,00% 90,00% 80,00% 70,00%

5,22% 2,98%

8,21% 14,09%

34,50%

18,36%

60,00%

8,60% 17,88% 22,90%

50,00%

Hydrocarbons

40,00% 30,00%

Others

57,30%

59,35%

20,00%

Biomass 50,62%

Jal Steel

10,00% 0,00%

Cement Holow cement block

Solid cement brick


Wall system 59


In the case of the clay brick, it is seen that 17.88% of their contribution to the carbon footprint refers to the use of biomass as fuel for its cooking. In this matter it should be noted that this figure does not include terms of CO2 emissions as a result of the material known as oakum, since according to Gomez (2008, 48-49), as it is a product that does not involve cutting down a palm tree, can be considered a zero balance condition, since when the oakum is burned, the palm still stand by their work capture CO2 through photosynthesis. In order to have a better understanding of the environmental impact, and particularly, the carbon footprint of these building systems throughout their life cycle, the chart below shows the surface of vegetation needed to counteract such impact. As the most common plant in the region of the study is the CocosNucifera, or commonly called coconut, it was the chosen plant to show these results. According to Flores (2010), one hectare of this species captures 37 Ton of CO 2. From it is already mentioned, the hollow block square meter would need 1,177.75 m2 of vegetation to absorb the CO2 emitted into the atmosphere during its entire life cycle. Meanwhile clay brick requires a green area of 992.60m2 and the cement solid brick is the constructive system that would occupy less area with 982.63m2 (Fig 8). Fig 8 Surface vegetation (Cocosnucifera) necessary to offset the carbon footprint of each m2

Green surface area (Cocos nucifera) m2

of wall system analyzed 1200,00

1177,74

1150,00 1100,00 1050,00 1000,00

982,63

992,60

Solid cement brick


950,00 900,00 850,00 Holow cement block

Wall system Furthermore, since the type of housing to which this study is directed (low cost house), has an area of approximately 100 square meters of wall, and the housing complexes that form are about 300 houses, would be required 3,533.25Ha, 2,947.86Ha and 2,977.8Ha for each housing complex with walls of hollow block, solid cement brick walls and clay brick respectively.

60


Conclusion Despite the significant differences between production processes, construction and transportation, the life stage turns out to be the greatest impact due to electricity consumption for indoor climate improvement in the three cases. That is why this phase is the most important and is where efforts should be focused to minimize its carbon footprint, so one of the main recommendations is to improve the thermal insulation characteristics of these materials. It is also necessary that the design of the houses meets the regional climatic conditions, and not be a standardized design nationally.

The construction phase is the second in importance due to the use of cement and steel, so it is recommended to review the construction procedures of the walls and the geometry of the pieces, in order to reduce their use and seek alternative elements that fulfill the same function, but whose production represents a smaller carbon footprint. It is also advisable to check the cement production processes, and especially its energy sources, as they generally come from fossil fuels.

In the case of the clay brick production, which uses biomass as energy source for its cooking, it is recommended that this comes from sustainable plantations where forestation renewal is guaranteed. It is also important to facilitate the use of local materials to reduce the energy consumption associated with transportation.

Although the wall of solid cement brick turns out to need a less area of green surface to offset the carbon footprint generated throughout its life cycle, it should be noted that the difference between this and the clay brick is less than 10m2, therefore currently either of these materials would be a good choice as wall construction system, compared with cement hollow block.

References Becker, M. y Barnet, L. (1985) Residential Wood combustion emissions and safety guidebook. Hiram Coll. Enviromental Resource Center (Department of Energy). Washington, D.C. Federal Electricity Commission (2009) http://www.cfe.gob.mx/en/laempresa/generacionelectricidad/thermalpower. Accessed 25 February 2009. Donaciano, L., González, A., Gordon, M., y Martín, N. (2007) Activated charcoal obtaining from the Coconut waste. UAM-Azcapotzálco. Thermofluids Department. D.F., México. Flores, I. (2010) Carbon Dioxide Emissions by Building Systems Covers of Affordable Housing in the Colima City. Architecture Master Thesis. School of Architecture and Design, University of Colima, Coquimatlan, Mexico. Gómez Azpeitia, G. (2008) Life Cycle Assessment of Economical Housing in Mexico. Wall Systems. Product 2: Inflows and Outflows Inventories. Extraction, transport manufacturing, construction and demolition phases (Project 66630-2007-01) Work report 2 to CONACYT. School 61


of Architecture and Design, University of Colima, Coquimatlan, Mexico. ISO 14040 (2006): Environmental Management: Life cycle assessment. Principles and framework ISO 14044 (2006): Environmental management: Life cycle assessment. Requirements and guidelines.

62


Assessing water footprint of companies in Colombia SuizAgua Colombia project Diana Rojas1, Mia Lafontaine3*, Francois Münger2, Maly Puerto1, Laura Suarez1, Anna Kounina4, Samuel Vionnet4, SebastienHumbert4 1 Swiss Agency for Development and Cooperation (SDC), Bogota, Colombia 2 Swiss Agency for Development and Cooperation (SDC), Bern, Switzerland 3 Quantis, Montreal, Canada 4 Quantis, Lausanne, Switzerland

* Corresponding and presenting author: Mia Lafontaine [email protected]

Abstract Stress on global water resources, especially in developing countries, is recognized as an important issue in terms of long term sustainability. From a company life cycle management perspective, there is therefore a growing demand for adequate methods of assessing impacts related to water use. For companies operating in developing countries, reducing pressure on water related environmental impacts should be fully part of the strategy. In order to reduce this pressure, the first step is to understand one‘s water footprint, including water withdrawal, consumption and pollution. This project, promoted by the Swiss Agency for Development and Cooperation in a public-private partnership, aims at evaluating the water footprint of four European-based companies operating in Colombia: Clariant (chemistry), Holcim (cement and concrete), Nestlé (food production), and Syngenta (Agribusiness). Additionally, in 2012, a new group of Colombian companies have joined this initiative. Special attention is given to the direct factory water footprint and the upstream (supply chain). In each corporate case evaluated, the supply chain was identified as a key contributor to the water footprint. Decreasing this aspect of the footprint is considered by companies as a complex and long term process. Communication about this water footprint is foreseen as a first step, as well as direct measures at the local level. In a second step, the different measures aiming at reducing, alleviating and possibly offsetting or compensating water footprint will be assessed in order to identify the alternatives to promote in priority. A comprehensive water footprint methodology has been specifically adapated for this project, considering impacts related to water consumption, to water withdrawal and water released into the watershed, to water pollution and also to turbined water related to hydroelectricity use. This methodology is in line with the current draft status of the ISO14046 standard for water footprinting. It is also compatible with full Life Cycle Assessment frameworks, reporting potential damages to the same areas of protection: human health, ecosystem quality and resource depletion. Key words: water, water footprint, scarcity, water pollution, Colombia

63


Introduction Water is directly linked to environmental, social, economic and political human dimensions. Water management is at the center of the sustainable development international debate, with many corporate initiatives taking place, such as with the WBCSD, the WFN and the CEO Water Mandate. Interest is rising on all fronts with increasing demand paralleled with decreasing availability and quality, generating more tension between different water users, including ecosystems. In corporate decision making, there is a necessity for a better understanding of water use and its related impact on ecosystems and human health, in order to improve water management. In this context, industry is strongly influenced by water availability, in quantity and quality, and accessibility, both directly on their operation but along their supply chain and downstream operations as well. Therefore, companies around the globe have an increasing interest in water-related issues, and they are moving forward to integrate water management in business plans and risk assessments. The Water Initiatives Section (WIS) of the Swiss Development Cooperation (SDC) seeks to contribute at finding solutions to the global challenges linked to water. It participates in programs and networks that aim at improving the provision of clean drinking water, enhancing sanitation, and upgrading irrigation in the agricultural sector. In 2009, the Swiss Ministry of Foreign Affairs aimed at strengthening collaboration between SDC and Swiss enterprises in Colombia. As a result of this effort, the ―SuizAgua Colombia‖ pilot project was launched, as a public- private partnership with Clariant, Holcim, Nestlé and Syngenta. It has been developed between end 2009 and 2012, and will have a follow up stage during 2013 and 2014, focused on the companies‘ further appropriation and direct use of the methodology and a scaling up process with a new group of 7 Colombian companies, and a water basin study. Additionally, SDC has launched the ―SuizAguaAndina‖ project to work with 10 companies and develop the water footprint know-how in Peru and Chile. .

Methodology For the SuizAgua Colombia project, a specific framework was developed based on existing methodologies for addressing water use impact assessment within the frame of Life Cycle Assessment (ISO 14044, 2006), inspired by the work of the Water group of theUNEP-SETAC Life Cycle Initiative working group (Bayart et al., 2010; Kounina et al., 2011)(Bayart, Bullek, Deschênes, Margni, Pfister, & Vince, 2010).

Data Collection

The water inventory data and information were collected for each company‘s operations – including purchases, energy and water use as well as waste and waste water treatment, for the years 2009, 2010 and 2011. The keyinventory data, on which the results are based, was provided directly by the partner companies.

The life cycle perspective accounted for virtually all water uses, direct or indirect (infrastructure, electricity consumption, fuels consumption, raw materials consumption etc.) through the use of the Quantis Water Database(Quantis, 2012), developed based on the ecoinvent database v2.2 (Frischknecht, 2006).

Pollution (thermal or chemical) of water was accounted for, using waste water characterization for direct waste water 64


effluent as well as databases for upstream processes, modeling both direct emissions to water as well as indirect emissions through air and soil. This also allowed for characterization of acidification, eutrophication, ecotoxicity and human toxicity impacts. These are used to assess the potential damage on ecosystem quality and human health, along with WULCA cause-and-effect chains related to water use and thermal pollution.

Two midpoints were selected for these assessments, which are the Scarcity assessment (Pfister et al., 2009) and the Water Impact Index (WIIX) method(Veolia, 2011). While the first evaluates a scarcity weighted equivalent consumption footprint, the second method estimates the impact on water resources availability by assessingchange in water quantity, quality and scarcity between inputs and outputs. The scarcity index used is the same, the Water Stress Index (Pfister, Koehler, & Hellweg, 2009). The quality index used in the WIIX methodology is calculated as a ratio of reference ambient water quality standardto the measured pollutant concentration of the effluent.This ratio is calculated on all pollutant and the minimum ratio is taken as the quality index(MEED & Agences d l'eau, 2003)(Legifrance, 2010).The WIIX calculates a Water footprint in equivalent WIIX cubic meters (m3 WIIX eq), by means of the Equation 1. 𝑾𝑰𝑰𝑿 =

𝑾 × 𝑸𝑾 × 𝑾𝑺𝑰𝑾 − 𝑹 × 𝑸𝑹 × 𝑾𝑺𝑰𝑹

(Equation 1)

Where W = water withdrawal, R = water released, Q is the quality index defined above and WSI the water stress index where the withdrawal or release occurs. Scope and boundaries of the study

The systems boundaries and functional unit were defined for each company. Assumptions were sometimes necessary in order to complete the water footprint assessment. All the systems were analyzed under the scope ―cradle to gate‖ and footprints were evaluated with respect to a year of operation as well as with respect to the products, as functional units. For most of the systems, water uses associated to transportation of raw materials and product packaging were neglected. Clariant

The analysis was focused on the annual production of one of the Clariant‘s plant (as functional unit). The plant is located in a zone with low water stress. The products are mainly Master batch, which are solid or liquid additives, used for imparting specific properties to plastics; as well as supplies for Oil and Mining Services (OMS). The plant has a list of supplies of nearly 2400 substances; most of them were grouped together and modeled as generic organic or inorganic compounds. Only country level location was available for some suppliers, therefore the WSI used represents a global average. Most of the flows within the system were estimated, except for the tap water use and treated waste water. The estimations were based on average equipment‘s consumption, values estimated by the company‘s technicians, mass balances and annual meteorological data (precipitation and evaporation) (IDEAM). WIIX associated to supply chain was modeled with database, using a global average WSI, thus its values could differ from reality. Holcim (Aggregates extraction site, Cement production site and concrete production sites)

The analysis was focused on the concrete production line, which includes the operations of four plants.The functional 65


unit was to produce 1 m3 of concrete. The concrete plants (Occidente and Sur) received the aggregates only from the Manas plant and the cement from the Nobsa plant. Occidente, Sur and Manas are located in Cundinamarca, Nobsa in Boyacá; all these locations have low water stress.

For the modeling of these five plants, several streams were not measured but estimated. The estimations made were based on mass balances, meteorological data and technical assumptions. Nestlé (Dairy farms, Florencia and Bugalagrande production sites)

The functional unit for this analysis was to produce 2 kg of powdered milk. The different stages of the production line were analyzed, starting at the dairy farms located in several municipalities of Caquetá which follow mainly the traditional model; the silvopastoral dairy farming, which involves trees plantation in grazing areas for optimizing production(Yamamoto, Dewi, & Ibrahim, 2007), has not a significant contribution yet because this farming model started its implementation a few years ago; so far, there are nearly 12 Figure 1. Scheme for Nestlé’s analyzed system

silvopastoral dairy farms compared to nearly 1800 traditional

dairy farms. The fresh milk is provided to the plant located in Florencia, Caquetá, where milk fat separation and milk precondensation are carried out. These subproducts are sent to the Bugalagrande plant, located in Valle del Cauca, where the powdered milk is produced among others products. All the locations of the powdered milk production line have a low water stress. For this system, the dairy farms calculations were based on estimations made by techniciansworking in areas relatedto milk collection, as well as using literature regardingwater pollution at the milking zone, drinking and service water use (Loaiza & Osorio, 2009). For cow manure pollution assessment, a leaching rate of 10% of manure‘s nitrogen was assumed(FAO, 2006). The concentration of leached nitrogen at grassland was estimated with leached nitrogen divided by the estimated runoff in the area. At the Florencia plant, all direct water uses were estimated by mass balances and technical assumptions, except for water withdrawal. At the Bugalagrande plant, all flows were based on technical assumptions; variations on water usesalong the years were estimated by extrapolations based on the powdered milk production changes.At this plant, electricity consumption for powdered milk production is accounted for all the dairy products section, where condensed milk and cream are also produced;so electricity was allocated bycost. Supplies allocation was also performed based on the requirements of precondensed milk and cream per product type.

Syngenta (Mamonal production site)

The analysis was focused on the annual production of crop protection substancesat the Mamonal plant, located in Bolivar. This zone has a high water stress. For this plant the supply chain was not modeled in detail but using general 66


categories, and several flows were estimated by mass balance. All industrial waste water is treated by evaporation and a posterior mud‘s‘ incineration, therefore this flow was assumed as consumed for the WIIX calculations. Domestic waste water quality was estimated based on literature (Brandes, 1978)

Results While the assessment included multiple indicators in parallel, to account for various impacts on water resources and quality, results presented here focus on a single indicator which integrates both quantitative and qualitative use, the WIIX. Clariant

When mapping the footprint by life cycle stage, as shown in Figure 2, the highest WIIX footprint is related to the raw materialsproduction, mostly titanium dioxide, for the first two years. It changes to the OMS in 2011. The WIIX of the factory operation is low compared to the one associated to the supply chain. With respect to the plant operations, the main contribution is related to indirect water consumption from energy production, whether it is electricity consumption, with an indirect evaporation of water in hydroelectricity production or from the cooling water where fossil fuels are consumed.

Figure 2. Overview of Water Impact Index for Clariant’sCota Plant annual production

The direct water inputs and outputswere reduced in the three years surveyed. However, it should be noted that industrial effluents do not meet the environmental quality standards (MEED & Agences d l'eau, 2003). For the first two years, the most penalizing pollutant found in the industrial effluent was mercury, with an average concentration of 0.002 mg/L whilein 2011, the output considered came from the tertiary treatment, where the most penalizing pollutant was phosphate, at an average concentration of 1.13 mg/L. The 2011 effluent had better quality than the industrial effluent in the previous years.

67


Table 1. Identified Hot spots at Clariant‘sCota plant

Table displays a hot spot mapping based on the midpoint and endpoint indicators, throughout the life cycle stages. The main impacts are once again found in the supply chain, with titanium dioxide and oil and mining services accounting for around 80% of impacts evaluated. Reduction of the WIIX footprint overtime was associated with the improvement of the waste water treatment plant in 2011. Other actions linked to reduction of the water footprint by direct water and electricity efficiency measures included: leak control, changes of appliances and raising awareness campaigns for the personnel. A comparison of the WIIX equivalent footprint as a percentage of the consumed water footprint at every life cycle stage showed that the WIIX was much more important in the

raw material production steps (WIIX of 58% of the consumed water footprint, compared to 1.5% in local operation), due to an increased scarcity in production locations that is not present locally at the manufacturing location. This confirms the risks linked to water upstream in the supply chain and the opportunity for Clariant to address this concern as part of asustainability and risk management strategy. Holcim

The overall footprint of concrete produced by Holcim was comparable to existing data (Quantis Water Database). With respect to the WIIX equivalent footprint, as displayed in Figure 3, it was the indirect water use for coal production that contributed the most, as well as indirect operations in the supply chain. 2011 also saw a drastic increase in local operations, which has been linked to the local floods causing groundwater infiltration, the necessity to pump these out, as well as the accounting of new flows.

Figure 3.Overview of Water Impact Index, Holcim, production line with final stage at Concrete Occidente

Table1shows main contributions to each stage of the water footprint assessment for the Holcim system. The highest water footprint identified is related to the Manas Aggregates plantwith direct water use in 2011, indirect water uses due

68


to electricity and coal consumption at Nobsa cement plant are also significant in years 2009 and 2010; Electricity at the inventory stage and Coal at the midpoint assessment stage. At the endpoint impact assessment, Coal consumption showed the highest contribution. Table1.Identified Hot spots at Holcim‘s concrete productionsystem having the final stage atOccidente plant.

For both production lines WIIX is significantly lower than water consumed (4-6%) because all the involved plants are located in areas with little to no scarcity (WSI = 0.012); however, it is worth noting that the quality of the water released to nature by the plants is either not optimal or taken from literature (Brandes, 1978), when compared to reference concentrations for ecosystems quality used for this study. The total result for potential impacts on human health and ecosystems quality are also shown; the highest contributions due to plant operation are related to the indirect water use due to energy consumption. Nestlé

The overall Water Impact Index footprint over the lifecycle chain of powdered milk production is shown in Figure 14. The highest impacts can be identified at the dairy farms due to the potential pollution from manureand theestimated use of herbicides in pastures crop. Water Impact Index results for direct operations of Bugalagrande and Florencia‘s plant are shown in ¡Error! No se encuentra el origen de la referencia.,A negative WIIX is also identified at Florencia‘s plant, as the water withdrawn has low quality and must be treated for its use; then treated one more time before returning it to nature. There is more output water than input water too, since water is removed from milk, this water is also treated before being released. Along the years, the water withdrawn had a BOD ranging from 630 to 860 mg/L while the water released had a BOD of 28.5mg/L to 65.6 mg/L. .

69


Figure 14. Overview of Water Impact Index, Nestlé’s powdered milk production line with final stage at Bugalagrande plant

Because milk is dehydrated, releasing water at the manufacturing plant, ¡Error! No se encuentra el origen de la eferencia.(Bugalagrande powdered milk production plant) shows a negative overall score, one that is quite variable over

the three years studied. For years 2010 and 2011,the water withdrawal increased, while the quality of the released treated water improved, the Biological Oxygen Demand (BOD) changing from 74 mg/L in 2009 to 12 mg/L in 2011. A negative WIIX is also identified at Florencia‘s plant, as the water withdrawn has low quality and must be treated for its use; then treated one more time before returning it to nature. There is more output water than input water too, since water is removed from milk, this water is also treated before being released. Along the years, the water withdrawn had a BOD ranging from 630 to 860 mg/L while the water released had a BOD of 28.5mg/L to 65.6 mg/L.

The WIIX due to dairy farm activities is related to water consumption and pollution. Water withdrawn for drinking water is significant but part of it is incorporated into the milk and other part returned to nature by the cows‘ excretions. It is assumed that 20% of the water used for cleaning at the farm evaporates and the remaining 80% is returned through runoff and infiltration water, which is polluted. According to literature (Loaiza & Osorio, 2009), Total Kjeldahl Nitrogen (TKN) detected at milking zones output could have an approximate concentration of 99.26 mg/L. TKN is the sum of organic nitrogen, ammonia (NH3), and ammonium (NH4+) in the chemical analysis of soils and water. Table 2 shows the water footprint of the powdered milk production is mostly linked to the dairy farms water uses, because of the potential water eutrophication due to manure pollution accounting for 93% of the estimated ecosystems quality impact. The electricity consumption at Bugalagrande plant is also one of the water footprint hot spots, representing 19% of the estimated human health potential impact. Programs for electricity and water use efficiency are under implementation. In order to improve the environmental practices at farms and reduce potential contamination, silvopastoral models are being promoted by Nestlé among the farmers. Within the SuizAgua Colombia Project, several Integrated Water Management plans are about to take place at around 80 dairy farms.

Table 2.Hot Spot mapping - Nestlé powdered milk production system

70


Once again, scarcity is low and keeps the WIIX equivalent footprint at a small fraction (. Acesso em: 29 jun. 2012. BRINGEZU, Stefan et al. Toward sustainable production and use of resources: Assessing Biofuels. 2009. UNEP. Disponível em . Aceso em: 20 jul. 2012. BRINGEZU, S. (Eds). Environmental consequences and interactions with changing land use. 156


proceedings of the scientific committee on problems of the environment (scope) international biofuels project rapid assessment. Disponível em: . Acesso: 20 mai. 2012. CASTRO, Antonio M.; LIMA, Suzana M.; Silva, João F. Complexo agroindustrial de biodiesel no Brasil: competitividade das cadeias produtivas de matérias-primas. 712 p.Brasília, DF: Embrapa Agroenergia, 2010. EMBRAPA. Soja em números (safra2010/2011). Disponível em: . Acesso em: 20 jun 2012. LIMA, Ângela M. F. Avaliação do Ciclo de Vida no Brasil: Inserção e perspectivas. 2007. 116 f. Dissertação (Mestrado em Gerenciamento e Tecnologias Ambientais no Processo Produtivo)Escola Politécnica, Departamento de Engenharia Ambiental, Universidade Federal da Bahia, Salvador, 2007. MENICHETTI, E.; OTTO. M. Biofuels: Energy Balance & Greenhouse Gas Emissions of Biofuels from a Life Cycle Perspective. Chapter 5. 2008. p. 81-109. In: HOWARTH, R.W.; RODRIGUES, Carla; ZOLDAN, Marcos et al. Sistemas Computacionais de Apoio a Ferramenta Análise de Ciclo de Vida do Produto (ACV). In: XXVIII Encontro Nacional de Engenharia de produção, 28., 2008, Rio de Janeiro. Anais eletrônicos. Rio de Janeiro: ABEPRO, 2008. Disponível em:. Acessoem: 12 set. 2011. SILALERTRUSKSA, T.; GHEEWALA S. Environmental sustainability assessment of palm biodiesel production in Thailand.Energy 43 (2012). 306-314. VIANA, Marcelo. Inventário do ciclo de vida do biodiesel etílico do óleo de girassol. 2008. 150 f. Dissertação (Mestrado em Engenharia) - Escola Politécnica, Universidade de São Paulo, São Paulo, 2008.

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UndeRstandable methOdology Bonding KnOwledge from cRadle-to-cradle for Undergrad Students: UROBORUS Maria Vitória Ferrari Duarte Tomé Katia Broeto Miller Raquel Naves Blumenschein Maria Clara Marques Sant Anna

(1) Faculdade UnB Gama, Área Especial 2 Lote 14 Setor Central Gama-DF, Cep: 72405-610, Brasília-DF, Brasil.

55 (61) 3107 8219, [email protected], www.fga.unb.br (2) Faculdade de Arquitetura e Urbanismo, Gleba A, ICC Norte, Campus Darci Ribeiro, Universidade de Brasília, Asa Norte, CEP: 70910-000, Brasília-DF, Brasil.

55 (61) 3107 7482, [email protected], www.fau.unb.br (3) Faculdade de Arquitetura e Urbanismo, Gleba A, ICC Norte, Campus Darci Ribeiro, Universidade de Brasília, Asa Norte, CEP: 70910-000, Brasília-DF, Brasil.

55 (61) 3107 7482, [email protected], www.fau.unb.br (4) Faculdade UnB Gama, Especial 2 Lote 14 Setor Central Gama-DF, Cep: 72405-610, Brasília-DF, Brasil.

55 (61) 3107 8219 [email protected]

Abstract Purpose: The goal of this article is to demonstrate results and difficulties of a didactic method used in the course of Engineering and Environment offered to freshmen on the Engineering program from the Universidade de Brasília (UnB) Gama Campus, seeking to discuss the inclusion of environmental parameters in the productive processes, and to establish connections among mining, manufacturing, and associated environmental impacts, and to minimize these impacts by recovering materials at the end of the product‘s life. Method: The method was divided in stages – definition of theme; a LCA exercise to draw the mass flows from cradle to cradle, including materials extraction and recovery in the recycling process; identification and analysis of environmental costs and impacts; evaluation and monitoring of methods and results obtained by students, for correction; and identification of gaps and opportunities for the project in the following semesters. 158


Results: In this topic the results obtained by the students themselves are presented, as well as the results from the application of the proposed didactic method. The students had the opportunity to build their own knowledge and to exercise concepts from Industrial Ecology and Lifecycle Analysis with this project. The mobile phones were disassembled and its components were identified and sent to the electronics recycling laboratory at the Gama Campus Faculty. The reports were revised and published in the Observatory for Waste, from the Universidade de Brasília and sent to local schools as course material for research. The elementary flows and the recycling techniques researched, the gaps and obstacles in obtaining the data were analyzed and will be used in the following semesters with the continuity of the project in the course of Engineering and Environment. Conclusion: The proposed discussion of solutions for a real problem facilitated the learning process. The disassembling of the mobile phones made it possible to identify components and characterize materials and to grasp the complexity and connectivity of the many productive chains involved. The creation of the elementary flows made it possible to comprehend the lifecycle stages from cradle to cradle, as well as the environmental impacts. Keywords: mobile phone recycling, electronic waste, LCA didactic methods.

Introduction The rapid increase both in human population and in consumption levels across the globe, natural resources are being depleted at an unprecedented rate. The general environmental overview made by UNEP in 2012 shows accelerated degradation of natural resources. If humanity intends to sustain its existence in this planet, we need to learn effectively that ―Earth is a complex physical/biological/anthropological totality. Life is a biophysical organizing force acting within an atmosphere itself created, over and below dirt and sea, where it has spread and developed. Humanity is a planetary and biospheric entity‖ (Morin, 2005, p. 23). The demand for the inclusion of environmental and social variables in the administration of raw materials and adoption of machinery and technology used in the productive processes, increases every day. Global alerts about collateral effects of this over exploitation become more frequently and public awareness prompts organizations to respond. Human activity on the planes is close to exceeding the sustainable limit of the support capacity and resilience of the system Earth (Hoffman, 1997)(UNEP, 2012). Political and productive organizations demand, thus, professionals capable of creating public policies and planning productive processes, considering environmental and social variables from the raw material extraction to the end of life of the products, evaluating and monitoring energy and matter flows, residues nd environmental impacts, to take more environmentally responsible decisions. A challenge which may be well rewarded with the contribution to the education of a environmentally and socially responsible engineer, is to adopt the premise that ―learning 159


organizations are those which succeed‖ and which cultivate commitment with the learning capacity, exercising in an integrated way, the five disciplines: ―personal mastery, creation of a shared view and systemic thought‖ as proposed by Senge (2009). The Unesco report on education in the XXI century defines horizons, principia and orientations, considering the need to develop a dynamic education, which involves the effective democratic participation which promotes international development and cooperation (Delors, 1996). The author considers the university as a ―place for culture and study open to all‖ and remarks that ―be recognized the mission of the University, in participating in the great debates related to the conception and with the process of transforming society‖. It should also be considered that the University should at the same time adapts to modern society and carry out its timeless mission of conservation and enrichment of a cultural patrimony, without which we would be mere machinery for production and consumption, according to Morin (2010). The author proposes also the investment in the aptitude to problematize and to connect knowledges. This connection is possible with the teaching of ecology, which is one of the disciplines which promotes the capacity to link, contextualize and globalize knowledge, for its multidisciplinary character, because it has as scope a complex system, which forms an organized whole. It is urgent that we exercise, in teaching engineering, the general systems theory developed by Bertalanffy (2010) and the principia of ecology of the ecosystem, since we need to understand, in a ever more populated and exploited world, for the population contingent and the creation and bad management of waste, that humanity and the environment for a total unity (Odum, 2009). The curriculum of the Engineering programs (Automotive, Electronic, Energy and Software) offered by the Gama Campus Faculty of Universidade de Brasília include the course of Engineering and Environment, with the goal of ―offer the student a basic education in environmental sciences for engineers of automotive, software, electronic and aeronautic systems. The course provides theoretical and conceptual support to make decisions based on critical and systemic analysis of interactions between engineering and the environment to act professionally in a responsible way, seeking sustainability. One of the challenges of this course is to conceive the didactic methods to raise awareness and train engineering students for a systemic view of the production process, considering the lifecycle thinking, in the scope of Industrial Ecology, seeking to understand the integration of supply chains, material and energy flows, and waste, and the respective social and environmental impacts associates, from cradle to cradle. Research and extension programs locally developed, using real scenarios with actual and relevant problem situations in the national and world scenarios, have been used as teaching method in this course since 2010, with published methods and publications in national and international congresses (TOMÉ et al, 2011a, TOMÉ et all 2011b). 160


1.

Method

The project method complied to the following stages: definition of theme which allowed to exercise the lifecycle thinking; an LCA exercise carried out by the students to draw the mass flows from raw material extraction, to carry out a LCA inventory, going through the production process to make the mobile phone components, until the final recovery of the mineral during the recycling process; the identification of costs and social and environmental impacts.

The monitoring and evaluation of planning and execution of activities and results obtained by the students were carried out, as well as identification of flaws, gaps and opportunities, seeking to continue with this project in the following semesters. The theme of the project was defined considering its global and national relevance, the complexity and capillarity of the mobile phone supply chain and the associated environmental and social impacts, the program and goals of the ―Engineering and Environment‖ course, as well as its integration with the research carried out in the Laboratory for the Built Environment, Inclusion and Sustainability (LACIS in Portuguese) and the Gama Campus Faculty from Universidade de Brasília, contributing to the institutional research project: ―Technical and economic viability of mobile phone recycling, seeking to implement a pilot facility for research and development of recovery techniques, recycling and re-use of materials from electronics in the UnB Gama Campus Faculty.‖ The method adopted was based in the premise that the construction of the knowledge from the identification of a real problem, providing a possibility of experimentation and to seek theoretical concepts, in the creation of proposed solutions to contribute to a ever more effective learning. The adopted scenario involves the lifecycle of mobile phones, from the cradle, in the extraction of raw materials, to cradle in the form of recycling, to provide a systemic view of all supply chains and its connectivity. The didactic method exercised in the course has been named Uroborus, a reference to cyclical phenomena. The students were organized in teams of seven with a leader chosen to communicate with the professor, receiving instructions and distributing and monitoring activities among the team members, organizing information and present partial results, corrections, reporting the results and organizing the presentation of a seminar to present and discuss results. The planning process and the implementation of the the project were evaluated in two aspects: (a) application of the method; (b) results obtained by the students. The application of the method was carried out seeking to develop leadership and cooperation skills and to establish connections and exercising concepts such as environmental performance, lifecycle thinking and sustainability. The evaluation of the method was carried out through the capacity to carry out activities, difficulties found and proposed solutions. For the execution of the project by the students three stages were defined: (1) planning and training of the students: a seminar was organized to present and discuss the problem situation, 161


considering the interface with the engineering courses, identification of the main legal landmarks involved, such as the National Policy for Solid Waste, created by Law 12.305/2012, methods for bibliographic review, creation of elementary flows, as well as definition of directives and monitoring systems, evaluation and presentation of results; (2) development: disassembling of mobile phones and identification of components and materials, identification of the mineral element used for making the components, bibliography review of location and estimate global and national reserves of these elements, technology, machinery, equipments, waste and GHG emissions, environmental impacts associated, production and disposal rates of mobile phones, creation of the elementary flows, identification of recycling techniques, costs, recovery possibilities and rates from unserviceable mobile phones and analysis of the complexity of the recycling processes, costs and environmental impacts associated; and (3) presentation and discussion of results in a seminar, and production of a final technical scientific report. Among the elements identified by the teams to research we mention copper, lead, lithium, palladium, platinum, silver and selenium. This project will continues over the next semesters of the course of Engineering and Environment, extending research on components and materials contained in the body, screens and accessories to the mobile phone, such as antennae and chargers. The research will also continue, with collection of quantitative data to compose the database to carry out lifecycle inventories.

Results The results obtained with the proposed didactic exercise must be presented considering, first the application of the method, and second the results obtained by the students. Among the relevant results we mention: the identification of methodological challenges, difficulties in accepting study themes related to the environment; difficulties in evaluating the development of skills and proposed. One of the methodological challenges in this discipline is to orient students recently admitted to the university to carry out a applied research project, since the courses in the engineering program have classes with over one hundred students. Another methodological challenge is the difficulty of perception, in the students, of the importance of environmental management disciplines, with other technical disciplines in the stricter core of the engineering curriculum. The perception of the professor during the semester, as in previous semesters, is that the students have difficulties in accepting the term ‗environment‘ as an important theme to be integrated in the engineering programs and which reflects in the professional exercise and reputational capital. This perception in founded in class discussions with the students and is supported by the analysis of professor evaluations carried out by Universidade de Brasília (TOMÉ et al. 2011a). 162


This project was proposed to develop the leadership, teamwork, perception of the importance of lifecycle management and learning in real life case studies. Nevertheless the perception of students of the skills developed is not measurable, and not possibly perceivable by all students in the short term. The demands on students from other courses and the limitations of students just recently graduated in high school, as well and the difficulties to perceive the importance of including environmental and social variables in the engineering education, contribute to the need of continuous overview of the activities, to ensure the quality of the work. The evaluation of the level of participation and commitment of students and the results obtained in the application of the method point to the possibility of absorbing concepts such as: lifecycle thinking, environmental performance of processes, products and services, and the concept of sustainability. The evaluation of the method was carried out with process and results indicators. Some stages were nevertheless compulsory and the teams had to complete them to proceed to the next stages, such as: (a) disassembling of the mobile phones for identification of components and materials, (b) definition of a chemical element present in the circuitry or the battery, for their environmental impact during production and disposal, (creation of a elementary mass flow from raw material extraction, through industrialization, (d) identification of recycling and material recovery techniques, and environmental costs and impacts associated (Table 1). The weekly monitoring ensured that the stages were carried out as planned and that needed corrections were applied. Some expected results were not obtained. First, the quantification of the materials, as well as the energy and waste from each stag, and will be the objectives of projects in the next semesters of this course. Second, it was not possible to identify the costs of the recycling techniques, as well as environmental impacts specific to each recycling process, for the lack of published materials, and will also be included in the scope of the projects to be developed in the next semesters. The summary of the identification and evaluation of the recycling techniques is presented on table 2. During the seminar for presentation of results, discussions about obstacles found by the students were promoted. Among them we mention: the access to published data, from the extraction of raw materials to recycling, and the difficulty to obtain data with companies, and the difficulty in managing knowledge on the management of lifecycle of electronic products for preparation of engineering students with no integrated database. According to Conmetro (2010) Brazil has a program for development of lifecycle inventories aligned with the International Lifecycle Platform. Nevertheless the involvement of the private sector is limited and there is much to evolve in the implementation of LCA in Brazil.

163


Table 1 Activities, results and difficulties

164


Activity

Mandatory

Carriedout

Visual characterization of

x

x

x

x

x

x

Partially carried out

Difficulties

components and materials Definition of the element contained in the circuitry Creation of the

Lack of published

elementary mass flows

quantitative data

from extraction to recycling Identification of

x

Lack of published data

x

No data identified on

environmental impacts from extraction x

Identification of

x

recycling techniques

costs, effluents, gases emitted and specific environmental impacts.

Table2 Analysis of recycling techniques for electronic waste Researched

Hydrometallurgy

Pyrometallurgy

Ellectrometallurgy

Bioleaching

Cost

Low

High

Low

Low

Complexity

Simple

Complex

Simple

Simple

Toxicity of

Not detailed

Not detailed

Not detailed

Not detailed

Soil contamination

Air pollution

Soil contamination

Soil

parameter

residues Environmental

contamination

impacts (qualitative data) Metals recovered

Copper

Copper, Nickel

Lead

High selectivity of

High recovery of

Few stages, Applied

Low energy

metals; Recyclable

metals (95%),

to all types of scrap

consumption

electrolyte

Associated with

with surface deposits

Electrometallurgy

of precious metals,

it achieves 99.9%

Recyclable

of recovery). Wide

electrolyte.

Lithium, Gold, Lead

Advantages

application to different types of


scrap.

Disadvantages

Doesn‘t accept

Emits gasses, loss

Need for pre sorting.

complex scrap,

of metal to

Slow process,

Slow, Generates

volatilization

Generates effluents

Not identified.

effluents.

Font: Costa (2010), Karper (2011), Mantuano et al. (2011), Veit (2001), Veit (2005), Yamaneet al. (2011)

Conclusion The students were capable of perceiving the complexity involved in the extraction of raw materials and the manufacture of mobile phones, and the importance of whole lifecycle management, as well as the need to wield tools to identify and quantify the flows of materials and energy and identify the negative environmental impacts from the extraction of raw materials for the manufacture of the mobile phones, to recovery of the elements in recycling, for making decisions to define materials and technologies. The difficulty to obtain data from the private sector and the need to continually research less toxic elements were discussed and considered as priorities for the planning of the next semesters. A massive investment in the education of consumers, professionals and organizations, as well as the political need of public managers on all levels, are essential to develop a database on LCA. Besides, mechanisms to communicate results to society are very important. This continues action project, integrating the academy and community. The theme of lifecycle analysis continues to be a challenge to all organizations and should be part, ever more intensely, of academic discussions, with more efficient communication to society. The experience of carrying out a applied research and extension project and the obstacles faced by the students in the conception of the proposal, from the identification of the problem to the creation of the hypotheses, collection and systematization and analysis of data were considered important to the development of team work skills in interdisciplinary teams. Students from the first semesters of the Engineering programs from the Gama Campus Faculty have been capable of carrying out lifecycle inventories and of making decisions to select less impacting raw material and productive processes. The targets proposed in this project were partially complied with, given the difficulty to obtain data in the bibliography review, and with direct requests to companies, which have difficulties to share information about their lifecycle inventories. Strategies will be established and perfected in the next semesters.


References Bertallanfy, L V (2009) Teoria geral dos sistemas. 4 ed. Petrópolis: Ed. Vozes.

Brasil (2010) Lei n. 12.305, de 2 de agosto de 2010. Institui a Política Nacional de Resíduos Sólidos; altera a Lei n. 9.605, de 12 de fevereiro de 1998; e dá outras providências. Costa, R C (2010) Reciclagem de baterias de íons de lítio por processamento mecânico. Porto Alegre: UFRGS, 2010. 129 p. Dissertação (Mestrado) – Programa de pós-graduação em engenharia de minas, metalúrgica e de materiais, Escola de engenharia, Universidade Federal do Rio Grande do Sul, Porto Alegre.

FGA (2008) Grade curricular dos cursos de Engenharia. Não publicado. Karper, A C (2011) Caracterização e Reciclagem de Materiais presentes em sucatas de telefones celulares. Porto Alegre: UFRGS, 2011. Dissertação (Mestrado) - Programa de Pós-Graduação em Engenharia Minas, Metalúrgica e de Materiais, Escola de Engenharia, Universidade Federal do Rio Grande do Sul, Porto Alegre. Dellors, J (1996) Educação: um tesouro a descobrir. Relatório para a Unesco da Comissão para a Educação no Século XXI. São Paulo: Cortez Editora. Mantuano, D P; Espionosa, D C R; Wolff, E;Mansur, M B; Schwabe, W K (2011) Pilhas e baterias portáteis: legislação, processos de reciclagem e perspectiva. São Paulo. Morin, E; Kern, A B (2005)Terra-Pátria. Tradução Paulo Azevedo Neves da Silva, 5ªed. Porto Alegre: Sulina. Morin, E (2010) A Cabeça bem-feita: repensar a forma, repensar o pensamento. Tradução Eloá Jacobina. 17ªed. Rio de Janeiro: Bertrand Brasil. Senge, P M (2009) A quinta disciplina: arte e prática da organização que aprende. Tradução: Gabriel Zide Neto, OP Traduções. 25ªed. Rio de Janeiro: BestSeller. Tomé, M V D F; Scardua, F P; Blumenschein, R N(2011) Educação para Responsabilidade Sócio Ambiental no Ensino de Engenharias Automotiva, de Energia, Eletrônica e Software na Faculdade UnB Gama. Porto Alegre: Anais do 3 Fórum Internacional de Resíduos Sólidos. Tomé, M V D F; Scardua, F P; Blumenschein, R N(2011) Educação para Responsabilidade sócio Ambiental no Ensino de Engenharia. Blumenau: Anais do XXIV Congresso Brasileiro para Ensino de Engenharia. Veit, H M (2001) Emprego do processamento mecânico na reciclagem de sucatas de placas de circuito impresso, 2001. Dissertação (Mestrado) - Programa de Pós-Graduação em Engenharia de Minas, Metalúrgica e de Materiais, Escola de Engenharia, Universidade Federal do Rio Grande do Sul. Porto Alegre. Veit, H M (2005) Reciclagem de cobre de sucatas de placas de circuito impresso. Porto Alegre: UFRS, 2005. Tese (Doutorado) – Programa de Pós-Graduação em Engenharia de Minas e Metalurgia e de Materiais, Escola de Engenharia, Universidade Federal do Rio Grande do Sul, Porto Alegre. Yamane, L H; Espinosa, D C R; Tenório, J A S (2011) Biolixiviação de cobre de sucata eletrônica. REM – Revista Escola de Minas, Ouro Preto. Vol. 64, no. 3.


Industrial Ecology

168


Proposal for technical and environmental performance improvement actions at an electricity cogeneration plant within the sugar/alcohol sector Guerra, João Paulo Macedo1 Junior, Jose Roberto Coleta1 Arruda, Luiza de Carvalho Martins1 Kulay, Luiz1 1 Polytechnic School of the University of Sao Paulo e-mail: [email protected]

Abstract The decentralization of the Brazilian electricity sector, which occurred at the end of the 1990s decade in association with the internal crisis of electricity supply at the beginning of the 21st century, has encouraged companies from sugarcane industry to produce electricity by burning sugarcane bagassein cogeneration plants. This action not only reduced environmental impacts intrinsic to the process, but also opened up perspectives for distilleries and annex plants to increase their products portfolio.In this study, potential scenarios for technically and environmentally improved cogeneration performancesvia the Rankine cycle are analyzed.The methodology employed in the study was initially an understanding and modeling of the vapor power systemsconventionally used by Brazilian distilleries in terms of electrical and thermal energy production and environmental impacts. Experts in vapor power systems have suggested acting in three areas for technical improvement: anelevation of the state functions of the steam from 67bar.aand 480°C, to 100bar.a and 520°C; regenerationand reheating. Eight case scenarios have beenprojected from arrangements among these conditions. Considering the systemic focus of the analysis, it was decided to consider a life cycle approach ―from cradle to gate‖. It was adopted as functional unit: "To produce 1.0 MWh of electricity in the cogeneration system". Thus, the product system covered not only the environmental burdens of the industrial stage, but also those generated during the agricultural production of sugarcane. The results obtained indicate that the proposed modifications are favorable by virtue of an increase in efficiency of the thermodynamic cycle in association with a reduction of environmental impacts of the product system for the evaluated categories. Key words: cogeneration, energy efficiency, Rankine cycle, sugarcane industry, environmental performance improvement.

Introduction Dating back around four decades, discussions, at world level, about the incorporation of renewable assets into the energy matrix have been taking place. Whether it is because of the economic instability of crude oil, the prospect of a reduction in its reserves, or the environmental effects that this would bring about, above all in terms of Climate Change, the use of cleaner energy sources has become an obligatory theme on the agenda of modern society. Brazil has one of the energy matrices with the highest participation of renewable source on the planet. In 2010 the contributions brought about by hydroelectricity, biomass – with wood and charcoal –,biofuels and wind energy totaled 45.3% of the energy offered in the country (MME 2011). Highlighted within this context is sugarcane participation, an asset in which the country is the world leader in terms of production. Even with a drop of 5.4% when compared to the previous 169


harvest, the national performance during the period 2011-2012 surpassed the level of 530 million tons of agricultural raw material (MAPA 2012).Sugarcane molasses are integrally consumed in the production of ethanol – for use in vehicles – and of sugar; though the remainder of the vegetal tissue of this graminea plant– made up of bagasse –was, until recently, discarded in an indiscriminated manner thus bringing significant environmental impacts. Developed technologies have come to correct this out of step situation by reusing the material as a source of steam and electricity for sugar and alcohol production processes themselves, thus making them self-sufficient in terms of energy. More recently, the prospect of exporting electricity into the national grid, above all during the idleness period of the distilleries and annex plants, motivated the sugar/alcohol sector to make more investments in these systems. This study proposes to make a contribution to this initiative evaluating, within technical and environmental merits, actions for improving performance of the electrical energy cogeneration units from burning sugarcane bagasse.

Method of Analysis The evaluation of technical merit was comprised of two stages: the proposal of improvement actions to the cogeneration system that operates in accordance with the Rankine cycle; and an analysis of the potential energy and environmental gains brought about by the same alternatives. The improvement actions proposal occurred by way of the formulation of hypothetical, though factual, operational scenarios. Therefore, two operating conditions for the cogeneration system were analyzed, starting from the state functions of the steam as it left the steam generator: at 67 bar and 480ºC and 100 bar and 520ºC respectively. For each condition four energy recovery alternatives were formulated, expressed in the terms of the Conventional; Reheating; Regenerative; and Composite (reheating + regeneration) cycles,totaling eight study scenarios. These are described in Table 1. Table 1: Electricity production scenarios in cogeneration systems defined from different state functions and energy recovery conditions. Case Scenario Description Standard (SS) Conventional vapor power cycle at 67 Bar and 480oC I Reheating vapor power cycle at 67 Bar and 480 oC II Regenerative vapor power cycle at 67 Bar and480oC III Reheat-Regenerative vapor power cycle at 67 Bar and 480oC IV Conventional vapor power cycle at 100 Bar and 520oC V Reheating vapor power cycle at 100 Bar and 520oC VI Regenerative vapor power cycle at 100 Bar and 520oC VII Reheat-Regenerative vapor power cycle at 100 Bar and520oC In the conventional cycle, superheated steamcoming from the steam generator expands almost completely until the condenser pressure.The cycle completes itself when the turbine exhaust steamis condensedand returns with the process condensateto the cycle and it is re-fed into the boiler. In the reheating cycle the steam does not expand to the condenser pressure in a single stage. The steam expands through a first-stage turbine and then is reheated is the steam generator. Such a flow after reheating is re-injected into the turbine second-stage.The regenerative cycle presupposes intermediate withdrawals of steam along the turbine. These steam flows are employed to heat the boiler feedwater, which occurs by indirect contact in heat exchangers. Finally, the Composite cycle associates reheating and regeneration in the form of a single cycle. The analysis of potential gains brought about by the improvement actions was made through a comparison of the overall energy efficiency results and of the quantity of exported electricity achieved with each scenario, when compared with the Standard Scenario (SS) under certain working conditions. In order to evaluate the environmental merit, a Life Cycle Assessment (LCA) was realized with focus on ―cradle to gate‖ of the cogeneration unit, taking as the objective of the study the electricity production. Under these conditions, the product system considered the agricultural stage of sugarcane production;the transport of this raw material to the distillery; ethanol production; and the cogeneration of electrical energy.For the product system modeling, the practices and 170


procedures of the State of Sao Paulo, whose average agricultural productivity reaches 90 t./ha, with peaks of up to 140 t./ha and five cultivations between land reforms (CGEE, 2008) were considered. Also, the reuse of industrial residues – filter cakes, vinasse and boiler ashes –, as well as the burning of the growing area as a preparation for harvesting (SOUSA & MACEDO, 2010) were admitted.It was decided not to take into consideration environmental impacts caused by the system in the form of Climate Change because of an admission that the carbon balance for ethanol production would be nil; and, that the contributions brought about by the other process elements, were, for the purpose of this analysis, of little significance.

Alternatives Proposition The models developed to represent the Conventional cycle; with Reheating of the steam; Regeneration; and Composite cyclesarerepresented in Figures 1 to 4 below. For all case scenarios, dry saturated steam at 2.5 bar of pressure is extracted from the turbine to be used in the ethanol production process and also to reach the deaeration set-point (110oC) then it returns to the boiler. The turbine exhaust steam at 0.1 baris condensed at the condenser unit and the liquidis pumped to the deaerator prior to be re-fed into the boiler and complete the cycle. Figure 1: Conventional vapor power cycle for a cogeneration plant (EES model)

Figure 2: Reheating vapor power cycle for a cogeneration plant (EES model)

In the cycle with Reheating, superheated steam is extracted from the turbine at an optimum pressure between 20-25bar, for both the conditions of work defined in the study. This band of variation was determined by a parametric analysis applying the graphic inspection method. Turbine exhaust steam performs the same trajectories as those realized in the Conventional cycle. The thermodynamic behavior of the scenarios under study was modeled by the computer program Engineering Equation Solver (EES), version v 9.146 (KLEIN, 2012).

171


Figure 3: Regenerative vapor power cycle for a cogeneration plant (EES model).

In the Regenerative Cycle (Figure 3), the number of heat exchangers was, once again, determined by a parametric analysis. It was verified that the use of more than three units in series to feedwater heating produced gains of efficiency that were of little significance. Figure 4: Reheat-Regenerative vapor power cycle for a cogeneration plant (EES model)

The basis of the calculation adopted in the simulations of all of the scenarios was based on anhydrous ethanol production in the autonomous distillery of sugarcane crushing capacity of 2.0Mtonof sugarcane per crop (180 days). The thermal energy consumptions – from 400 kg of saturated vapor at 2.5 bar –, and electricity – of 30 kWh/t. of processed sugarcane – necessary for the production of ethanol, are not affected by the scenarios previously presented. The excess of the electrical energy generated in the cogeneration unit is exported to the electricity grid.

Conceptual basis for the LCA study This LCA study was carried out starting from the theoretical registration described by the norms ABNT NBR ISO 14040 (2009) and 14044 (2009). Thus, in what is referred to as Objectives Definitionthe initiative proposes to carry out an environmental analysis of the actions for an improved performance of the cogeneration units from the burning sugarcane bagasse.In terms of Scope Definitionthe following requisites were established: Function:to produce electrical energy in the cogeneration system. Functional Unit (FU): to produce 1.0 MWh of electricity in the cogeneration system. Reference Flow (RF): the reference flows will be established in terms of sugarcane bagasse consumption for each one of the eight scenarios under analysis. Product System: It includes the sugarcane agricultural production stages; transport; industrial production of ethanol; and electricity cogeneration, this last system described in the form of the eight scenarios presented in Table 1. Data Source: the modeling of the product systems was essentially carried outfrom secondary data. An exception occurred for the cogeneration Standard Scenario (SS) for which it was possible to collect primary data in what was referred to the boiler efficiency. Data Quality: the Temporal Coveragecomprised of the two year period 2009-2010. As the Geographical Coverage was defined for the State of Sao Paulo; andfor the Technical Coverage,the processes and technical features previously described were admitted. 172


Allocation: realized only between ethanol and sugarcane bagasse, for the criteria of energy content. Impact Categories and method for Impact Evaluation of the Life Cycle (IELC): with the intention of obtaining an environmental performance profile of a wide spectrum, generated by a grouping of analytical indicators, the ReCiPe Midpoint (H) – version 1.06 method was selected. For the definition of the environmental profiles, all of the impact categories of the reference model were employed, except: Climatic Changes; Ionization Radiation; Marine Eutrophication and Marine Ecotoxicity; and Urban Soil Occupation (GOEDKOOP et al. 2012).

Results Technical Evaluation

Table 2 shows the results of overall energy efficiency and of net gains in terms of electricity generation for each case scenario, measured in relation to the Standard Scenario. Table 2: Results of scenarios simulationsprojectedby EES models Boiler Pressure: 67 Bar Case scenario

SS

I

II

Boiler Pressure: 100 Bar

III

IV

V

VI

VII

Net power output (kWh/ton of sugarcane)

121,8 127,8 132,0 142,0 130,3 137,0 142,6 151,9

Net power exported (kWh/ton of sugarcane)

91,8

97,8

102,0 112,0 100,3 107,0 112,6 121,9

Cooling Tower water consumption (kg/ton of sugarcane) 437,7 416,4 384,8 346,3 395,4 372,6 331,9 299,6 Deionised water consumption (kg/ton of sugarcane)

58,0

83,2

63,1

87,6

54,0

82,8

58,8

91,7

Overall Yield (% )

67,9% 68,9% 69,6% 71,4% 69,3% 70,5% 71,5% 73,1%

Net electricity gain (% )

0,0%

6,5% 11,1% 22,0% 9,3% 16,6% 22,7% 32,8%

From the data in Table 2, it can be noted that the results in terms of energy efficiency will be improved both by increasing vapor pressure when leaving the boiler, and bythe Composite Cycle bringing about greater energy benefits than its homologues.So much so, that it is true to say that for Scenario VII – with the highest overall energy efficiency – the specific rate of exported electricity reached the level of 121.9kWh/tof sugarcane, which corresponds to an increase of 32.8% in relation to the Standard Scenario (SS) performance. Simultaneously, the makeup water consumption in the cooling tower, and also makeup water to the boiler were also reduced by 21.1%in relation to the initial Standard Scenario (SS). Environmental Evaluation

Table 3 shows the results of the Environmental Performance Profiles, generated by the IELC of the eight case scenarios from the application of the ReCiPe Midpoint (H) – version 1.06 model. Table 3 – Environmental Performance Profiles of the eight case scenarios referring to the generation of 1.0 MWh Impact category

Unit

STD

I

II

III

IV

V

VI

VII

Human toxicity

kg 1,4-DB eq

37,77

35,49

33,99

30,99

34,58

32,43

30,77

28,47

Photochemical oxidant formation kg NMVOC

54,54

51,19

49,09

44,70

49,92

46,79

44,47

41,07

Particulate matter formation

kg PM10 eq

89,65

84,15

80,68

73,48

82,05

76,91

73,09

67,51

Terrestrial acidification

kg SO2 eq

22,30

20,93

20,07

18,28

20,41

19,13

18,18

16,79

Freshwater eutrophication

kg P eq

0,018

0,017

0,016

0,015

0,016

0,015

0,015

0,014

Terrestrial ecotoxicity

kg 1,4-DB eq

3,13

2,94

2,82

2,57

2,87

2,69

2,55

2,36

Freshwater ecotoxicity

kg 1,4-DB eq

1,12

1,05

1,01

0,92

1,02

0,96

0,91

0,84

Agricultural land occupation

m2a

801,62

752,44

721,45

657,03

733,68

687,74

653,53

603,67

Natural land transformation

m2

Water depletion

m3

13,32

12,54

11,72

10,61

12,02

11,22

10,31

Metal depletion

kg Fe eq

0,63

0,59

0,56

0,51

0,57

0,54

0,51

0,47

Fossil depletion

kg oil eq

40,19

37,74

36,17

32,95

36,79

34,49

32,76

30,27

6,37E-05 7,53E-05 4,04E-05 4,33E-05 5,14E-05 5,13E-05 1,33E-05 2,70E-05 9,55

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It can be noted in advance that the improvement of the energy performance system is accompanied by a reduction of the environmental impacts for all of the evaluated categories, an outcome to a certain extent foreseeable. As well as this, the tendency, both in absolute and relative terms, of the production of superheated vapor to 100 bar and 520ºC resulting in greater environmental gains, is confirmed. Once again Scenario VII, whose environmental performance improvements measured in relation to the Standard Scenario (SS) varied from 24.0% up to 28.3%over all of the analyzed impact categories, was confirmed.

Conclusions The concepts of regeneration and reheating showed themselves to be considerably effective – above all when combined in the form of a Composite Cycle – for the effect of cogeneration energy performance improvement by burning sugarcane bagasse. The results obtained through this study only ratified the expectation of the sugar/alcohol sector of being able to export electricity to the national grid during the installation‘s idleness periods. The alternatives for the technical performance improvement of the Rankine cycle also reverted in a reduction of environmental impacts in relation to the scenario defined as a reference for the analysis of all of the examined environmental impacts. In a broad manner, this analysis confirmed the tendency that the more sustainable use of natural resources is directly related to the adoption of more efficient energy practices for cogeneration systems.

References ABNT – Brazilian Association of Technical Standards.NBR 14044 - Gestão ambiental Requisitos e orientações. 2009. 52 p. ABNT – BrazilianAssociationofTechnical Standards. NBR ISO 14040 - Gestão ambiental Princípios e estrutura. 2009. 27 p. CGEE – Centro de Gestão e Estudos Estratégicos. Bioetanol de cana-de-açúcar: energia para o desenvolvimento sustentável. Rio de Janeiro: BNDES, 2008. 316 p. GOEDKOOP, M., HEIJUNGS, R., HUIJBREGTS, M., DE SCHRYVER, A., STRUIJS, J.: Description of the ReCiPe methodology for Life Assessment Impact Assessment, http://www.lciarecipe.net retrieved sept. 2012. KLEIN, S.A.: Engineering Equation Solver (EES) v9.146. 2012. Mechanical Engineering Dept. University of Wisconsin-Madison. F-Chart Software: http://www.fchart.com. 2012. MAPA – Ministério da Agricultura, Pecuária e Abastecimento, Secretaria de produção e agroenergia, açúcar e álcool no Brasil. Estatísticas do setor. Safra 2010 – 2011. Brasília. 2012. MME – Ministério de Minas e Energia - Resenha Energética Brasileira – 2010. Brasília. 2011 SOUSA, E. L. L.; MACEDO, I. C (Org.). Etanol e bioeletricidade: a cana de açúcar no futuro da matriz energética. São Paulo: Luc Projetos de Comunicação, 2010. 315 p.

174


Industrial Symbiosis in the Industrial Area of Villa El Salvador Isabel Quispe, Ramzy Kahhat, Jair Santillán, Roberto Romero

Abstract Purpose. The aim of this study is to evaluate the potential for Industrial Symbiosis between the companies located in the industrial area of Villa El Salvador, the community and the town hall. Moreover, it seeks to adapt the Industrial Symbiosis model in a context of predominant micro and small businesses. Methodology. Information about the industrial area and selected industries was gathered using several methodologies, such as experimental observation, unstructured interviews to general managers of each industry and local government officials, and literature review for selected processes. These techniques made possible the identification of key residues for each industry and current segregation and disposal management options. Additionally, preliminary material flow diagrams were created to identify current and future industrial symbiosis in the area. Results and Discussion. Study results indicate that the main solid waste found in the industrial area are scrap metal and metal shavings, slag, natural and synthetic leather pieces, scrap wood, sawdust, organic waste and wood boards. The informal recyclers were also identified as important agents in the final disposal management options for the companies. Conclusions. Industrial Symbiosis applied to the industrial area of Villa El Salvador could be rewarding for the businesses and the community. It is necessary to adapt the concepts of Industrial Symbiosis to the reality of the studied area in order to maintain the positive impacts of the present interactions, like the ones given by the informal recyclers. Keywords: Industrial Symbiosis, Villa el Salvador, small business.

Background Industrial Ecology (IE) is a relatively young scientific field, in analogy to biological ecology, can be defined as "the study of technological organizations, their resources, their potential impacts on the environment and the ways in which their interactions with the natural world can be restructured to allow global sustainability "(Graedel and Allenby 2009). There are several tools regarding this area, such as scenario analysis, material flow analysis, eco-design, life cycle assessment, industrial symbiosis (IS), among others. As an IE tool, industrial symbiosis seeks the beneficial synergy of two or more industries through the exchange of waste in order to use them as new resources that promote the sustainability of the industrial system (Chertow, 2007). IS seeks to systematically transform the waste from one industry into another raw material, in order to achieve an optimal and environmentally responsible use of resources. The IS encourages the conversion of a traditional open linear system into a closed loop with interdependent relationships as found in nature. Industrial symbiosis, despite their recent creation in the mid-nineties, has some successful stories around the globe. The most striking example is Kalundborg, in Denmark, which inspired SI implementation worldwide. The industrial symbiosis in this Danish park is characterized by the exchange of steam, heat, fly ash, organic wastes, and others from different industries including a power plant, oil refinery plant, gypsum industries and chemical pharmaceutical industries (Graedel and Allenby, 2009), achieving the reduction of approximately 240,000 tons of carbon dioxide, 3'000, 000 cubic meters of water, among others benefits (Kalundborg Symbiosis, 2012). Other successful stories include Kwinana in Australia, Kawasaki in Japan and Guitang Group in China, 175


(Van Berkel 2009; Chertow, 2007; Zhu 2007). While the concept of SI has been successfully applied in some parts of the world, its spread is still limited. In Latin America there are no reported cases of IS, perhaps because so far it has been used only in a context where there's a predominance of large industries. In this sense, there has never been a study on a smaller scale, such as for small and medium enterprises (SMEs), to determine the feasibility of using this tool with the goal of reducing the environmental impact. Studies show that, of all SMEs in the world, 11% are in Latin America. Moreover, SMEs generate 81% of the jobs existing in Latin America (CISCO, 2011). In Peru, these enterprises comprise the 98% of the companies (SUNAT 2005). One area that represents the development of SMEs in the city of Lima, Peru is the district of Villa El Salvador, this area has grown economically since the end of the eighties thanks to government support and the United Nations Industrial Development Organization (UNIDO) (ECLAC, 2000). The successful implementation of IS in different countries, has given rise the question of the possibility of extending the study of this tool not only to large industries, but also to small ones. The present study aims to conduct an Industrial Symbiosis analysis in the context of small and micro enterprises in the district of Villa El Salvador in Lima in order to propose improvements that reduce the environmental impact associated with the consumption of resources and waste management in the area.

Methodology For the present study, SMEs in Villa el Salvador were analyzed in two stages. In the first stage, we studied the most representative industries of the areas of metallurgy, foundry, carpentry and shoe. To achieve this goal, an industrial mapping was made in order to select the representative industries for each category within the boundaries of the industrial zone. The techniques used in the selected companies included experimental observation of the different processes, identification of inputs and outputs, and the use of unstructured interviews with employers. With this information, it was possible to get a detail of key residues of each industry and current methods of segregation and disposal. In the second stage, the zone outside the boundaries of the industrial area was mapped in order to identify potential companies that might interact with those already studied in the first stage in order to improve the proposal of a symbiosis model. In the last stage of the study, a preliminary model of symbiosis was made in the district. This phase included a literature search related to the possible use of generated waste as a raw material in the industrial sector of Villa el Salvador. Some possible connections of industrial symbiosis were placed in schemes in order to propose a symbiosis model according to the context and business of the district; additionally, the entry of new enterprises that optimize the symbiotic model were studied and proposed.

First phase of the study - Description of the main companies The first phase of the study includes the industrial district of Villa El Salvador. This space comprises four main industries: carpentry, with 29% of all enterprises; metalworking (30%); shoes (11%), and foundry (4%) (PIVES, 2012) The carpentry industry is the most important in the district of Villa El Salvador. The analyzed companies were classified between those involved in the production of furniture for export and those for the local market. Additionally, there are sawmills that sell plates, blocks, pieces and strips of wood. 176


The companies in the field of metalworking are responsible for making machines, mainly used in the food industry. The processes taking place in these companies vary depending on the parts that are to be obtained. In the area of footwear, companies produce pieces of natural and synthetic leather in various designs and sizes, they also make dress, orthopedic and security shoes. Some companies send orders to the province while others sell their products in their own stores in the district. Regarding the casting category, only a few companies are still engaged in this activity. As indicated by the former president of the Foundries Association of Villa El Salvador (AFAPIVES, for its acronym in Spanish), a lot of these companies had changed to the carpentry sector. These companies make brass, cooper and aluminum pieces. Chart 1 lists the most important processes of the four industries listed above; it is accurate to consider these as standard processes in many enterprises of the area. Chart 1 - Main processes of the industrial area of Villa El Salvador Metalworking Foundry Footwear Lathing Molding Design Milling Selection Cutting Brushing Melting Sewing Grinding Casting Roughing Bending Unmolding Pre-forming Polishing Gluing Refinement

Carpentry Design Drying Pre-machining Drawing Machining Assemble and Polishing Varnishing and Refinement

Second phase of the study – Description of the main agents In this second phase, companies outside the boundaries of the industrial area within a radius of 2.5 kilometers were studied in order to expand the horizons and ensure a better symbiosis model proposal. Various industries were found, and the few most relevant of them to the project will be described. Two farms were found in the area, mainly chickens and pigs are bred in them; significant aspects of the processes are the abundant use of water and the large amount of organic waste generated. These farms cater to nearby markets and some restaurants along the South Pan-American Highway. In the area, two large warehouses were found. These belong to an important department store chain and a logistics operator. These enterprises use wooden pallets for their products, at the end of their useful life these pallets are disposed with other solid waste and/or sold to recycling companies. In the center of the district of Villa El Salvador was found the Biotech Complex #26, funded by the government through the Ministry of Environment. The main activities carried out at the site are composting and growing of various plant species, and the maintenance of oxidation ponds for wastewater treatment. Around the area, two main markets were detected, one is the fish market of Villa Maria del Triunfo, the other one is the Unicachi Market, located in the west of Villa el Salvador. Both have a high flow of materials and waste, mainly organic. Another enterprise worth mentioning is a concrete mixer company; which prepares the mix and 177


transports the concrete to the construction sites. The city hall of Villa El Salvador is an important agent because of the series of services offered to the community, such as park and garden maintenance, civil construction, and waste management. The latter operation is disorganized; there is not separation of potentially recyclable or reusable waste.

Findings and Diagnosis In the metalworking industry, electrical energy is an intensive input, and they use pieces of metal as raw material. The treatment given to residues varies; only a few companies make a metal separation, while most of them dispose all the residues without distinction. Companies often sell their scrap metal to informal recyclers who visit them regularly. Other companies keep some of their waste for reuse, but because of a lack of capacity, they tend to accumulate. An exception was seen in a company that reuses metal shavings as counterweight for its machines. The main fuels used in the foundry industry are burned oil and petroleum; while inputs are basically scrap metal. The generated waste is not sorted, but randomly stored in the free spaces of the plant. Slag is sold to informal recyclers, since this metal can be recovered for re-foundry. The annual amount of generated slag reaches the order of tons. The scrap that has not been used is disposed as waste. Usually footwear companies do not segregate their waste. Sporadically, leather scraps are given to informal recyclers. The study showed that one company used its waste to manufacture souvenirs for their clients (e.g. purses); however, this activity is not done regularly. Carpentry enterprises give away or sell their residues to recyclers or, in some cases, directly to small companies that manufacture toys or wood ornaments. Some entrepreneurs mentioned that waste can be used as filler for livestock spaces. Chart 2 provides a list of the main solid waste generated by each sector processes, these are potential exchange material for an industrial symbiosis model. Chart 2 Main solid residues per industry in the industrial Area of Villa El Salvador Metalworking Foundry Footwear Carpentry Pieces of metal: brass, Metal slag Leather scraps Wood pieces steel and aluminum. Metal shavings Synthetic leather scraps Shavings Metal shavings Scrap metal Sheepskin scraps Sawdust Paint Cans Foundry Sand Varnish Cans Remains of paper Water with traces of Remains of cardboard varnish Blow Plastic Packing (Stretch Film) Industrial lubricant The solid waste management in the district is inadequate, segregation is not detected either in the city hall or in the enterprises, and therefore, large amounts of reusable material are lost. Currently, informal recyclers are actively involved in the management of solid waste, they carry the collected waste to temporary storages where people buy and sell certain types of material available for recycling or reuse. It is also important to note that the original distribution of the industrial area differs from the one obtained by the industrial mapping. Today, parts of the industrial area have changed from industrial to commercial; this has led to the emergence of banks, restaurants and supermarkets in the area. Additionally, some small industries are moving to the surrounding area.

178


Proposed Industrial Symbiosis Model Markets Unicachi Market

Fish Market

Organic Waste City Hall

Organic Waste

Biotech Complex

Compost

Pallets

Compost

Logistic Warehouses

Sawdust Sawdust

Farms

Sawdust

Carpentry

Footwear Scrap metal

Metalworking

Foundry Scrap metal

Metal Structures

Metal slag

Industrial Area

Graphic 1 - Proposed Industrial Symbiosis Model in Villa El Salvador During the development of the first stage of the research, industrial symbiosis connections based on solid waste exchange were proposed. However, a series of limitations and constraints were found in the industrial area due to the need to find agents that can give greater use of solid waste as inputs. The development of the second phase of the project enabled a greater number of symbiosis connections. Graphic 1 shows the proposed model of industrial symbiosis for the analyzed companies in Villa el Salvador. The proposed interactions are described in the current section. A first set of IS connections is formed between metalworking and foundry companies in the industrial area and enterprises that make metal structures in the district of Villa El Salvador. Not reusable scrap for manufacturing enterprises can be taken to the foundry companies, where the scrap would be classified and used as feedstock for the production of new metal parts. This process can only be used for the workable metals in the small industries, such as aluminum, copper, bronze, but not for steel, as companies in the industrial area does not have the technology that allows this work. Additionally, the remaining slag from the foundries can be reused in metallurgy enterprises, for example, in order to make counterweights for machinery. The carpentry enterprises show the greatest potential for industrial symbiosis, the wooden pallets discarded by logistics operators can be used as input for carpentry. A current connection is the direct transfer of sawdust and shavings to farms for livestock. Additionally, waste wood can be delivered to the biotech complex in order to make compost. Another proposal is the use of shavings and sawdust to form orthopedic shoe insoles, this is possible with the adoption and implementation of forming processes. The leather reuse already exists in footwear small industries, but no additional companies that can use this type of waste have been detected within the studied area. For this reason it no additional connections are proposed, but it is recommended to improve and promote existing internal reuse practices. It is proposed an organic waste flow between farms, the biotech complex, markets and the city 179


hall. The farms and markets could offer their organic waste to the biotech complex for composting. It is also possible to use organic waste as fertilizer for the maintenance of the gardens of Villa El Salvador. The mentioned connections are proposed according to the guidelines described by Chertow (2007), in which the industrial symbiosis is limited to the transfer of waste between companies and the participation of recycling agents is not possible. However, the social reality of Villa El Salvador shows an uncontrolled growth and a large number of people belonging to lower socio-economic levels according to APEIM (46% in the SES "D" and 20% on the SES "E"). For this reason informal recycling is one of the most representative sources of income, and it can‘t be ruled out. The city hall is currently working on the formalization of the recycling activity, promoting the formation of a guild that supports the municipal activity, since this activity represents the livelihood of many families in Villa El Salvador. The implementation of a complete symbiosis model can go against this objective, it is necessary to consider the industrial symbiosis connections adapted to the district's reality with the maintenance of existing relationships, thereby preserving the positive social and environmental impacts of the system.

Proposed new additions In the proposed industrial symbiosis model, it was found that many residues are not used, are used within the same sector (e.g. small footwear industries) or, in other cases, not in a constant manner (smelting slag). For this reason, it is proposed to involve other companies to optimize the use of waste, thus generating a new model proposal. Markets Unicachi Market

Fish Market

Organic Waste City Hall

Organic Waste

Biotech Complex

Compost

Compost

Pallets

Logistic Warehouses

Sawdust Leather Scraps

Sawdust

Farms

Sawdust

Carpentry

Footwear

Garment

Scrap metal

Metalworking

Foundry Metal slag

Scrap metal

Metal Structures

Industrial Area Metal slag Concrete mixer

Graphic 2 - New additions to the industrial symbiosis model in Villa El Salvador Graphic 2 shows the proposal of new connections in order to use the main residues of all the studied agents. Because within the industrial sector, the footwear industry is made up of companies that reuse their waste internally, an additional proposal is the creation of small garment companies which can work with part of the unused leather pieces. An additional reference obtained is the using of metal slag as part of construction material. It is proposed the implementation of processes of metal slag reuse in concrete production as mentioned by Khidhair (2009). New proposals arise around the carpentry industry, the use of shavings and 180


sawdust with special resins with the aim of produce wooden agglomerates. This kind of industry is not found in the district, but it may be a business opportunity. A further proposal is the use of shavings and sawdust to produce bio-ethanol or to form carbon briquettes.

Discussion When searching for reuse options for the main enterprises in the industrial area of Villa El Salvador, the greatest potential was found in carpentry industry due to the presence of other companies capable of utilizing wooden waste in their operations. Similarly, in the second stage of the project, companies with residues that can be used in carpentry were found. The proposal of new additions in the model and the adoption and implementation of new technologies would allow a greater potential for industrial symbiosis in this context. Implementing an industrial symbiosis model is only possible if SMEs from the same industry exchange their waste in the area as a whole and not individually. This is because the small amount of waste would not allow the constant flow of material needed to maintain the system. The change from industrial to commercial zone in Villa El Salvador threatens a possible implementation of the model, it is necessary a commitment from all stakeholders. The development of the research has uncovered the important role of informal recyclers in the current solid waste management in Villa El Salvador. The proposed industrial symbiosis model does not consider these agents; however, a good contribution to the economic development of the population would be the participation of the recyclers to the supply chain of the proposal.

Acknowledgments The research team is grateful for the funding from the Engineering Department at the Pontificia Universidad Católica del Perú (PUCP), also for the support of the Municipality and business associations in Villa El Salvador. Additionally, the collaboration of Raul Flor with the gathering of information in the initial stage of the investigation is well appreciated.

References Baas L. (2011). Planning and Uncovering Industrial Symbiosis: Comparing the Rotterdam and Östergötland regions. Business Strategy and the Environment. 2011, 20, 428-440. Barnes, H. 1992. Fertile project exploits recycled wastes. Survey on Denmark. The Financial Times, 8 October, 5. Berkel, R. Comparability of Industrial Symbioses. Journal of Industrial Ecology. 2009, 14, 483485. Centro Nacional de Producción Más Limpia de Guatemala (2009). Guía de Producción más limpia – Industria Forestal. Chertow, M. ―Uncovering‖ Industrial Symbiosis. Journal of Industrial Ecology. 2007, 11, 11-29. Economic Comission for Latin America and the Caribbean (ECLAC) (2000). Desarrollo Económico Local y Descentralización en América Latina. Disponible en: http://www.eclac.cl/publicaciones/xml/1/6081/lcr2016e.pdf. Graedel TE, Allenby BR. Industrial Ecology. 3er ed. Prentice Hall. Upper Saddle River, NJ; 2009. Groover, M. (2007). Fundamentos de manufactura moderna (3 ª ed.) México: McGraw-Hill Interamericana. Kalundborg Symbiosis. http://www.symbiosis.dk/ (Acceso Marzo 2012) Khidhair J.M., F. Abbas, M.O. Abbas. Using of steel slag in modification of concrete properties. Eng. & Tech. Journal, 2009, 27. Municipalidad de Villa El Salvador (Munives 2012). Historia de Villa El Salvador. Disponible en: http://www.munives.gob.pe/VillaElSalvador/historia.asp. Pinzón, A. (2009). La Simbiosis Industrial en Kalundborg, Dinamarca. Available on: dialnet.unirioja.es/servlet/fichero_articulo?codigo=3647936 R López, P. A. Nicola, O. A. Manfredi, C. F. Pérez (2003). Procesamiento de Escorias de 181


Aluminio, Experimentación a Escala Piloto. Jornadas SAM, Conamet, Simposio Materia 2003. Seoánez Calvo, Mariano. 1998. Ecología Industrial: Ingeniería Medioambiental aplicada a la industria y a la empresa. 2da edición, Mundiprensa. Shishir K., Jung-Hoon K., Sang-Yoon L., Sangwon S., Hung-Suck, P. (2011). Evolution of ‗designed‘ industrial symbiosis networks in the Ulsan Eco-Industrial Park: ‗research and development into business‘ as the enabling framework. Journal of Cleaner Production. 2012, 2930, 103-112. Superintendencia Nacional de Administración Tributaria (SUNAT). Conglomerado Estadístico, 2005. Zhu Q, Lowe E., Wei Y. y Barnes D. (2007). Industrial Symbiosis in China. Available on: http://www.rshanthini.com/tmp/CP551SD/JofIEIndustrialSymbiosisInChina.pdf.

182


LCA & Rural Development


Carbon payback times for petrodiesel substitution by palm biodiesel from expansion of plantations in Brazilian Amazon Marcela Valles Lange*, Simon Gmuender**, Rainer Zah**, Cássia Maria Lie Ugaya* * Programa de Pós-Graduação em Engenharia Mecânica e de Materiais, Universidade Tecnológica Federal do Paraná, Av. Sete de Setembro, 3165, Rebouças, CEP 80230-901, Curitiba – PR, Brasil **Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129,CH-8600, Dübendorf, Switzerland

Phone: ++55 41 33104661 Fax: ++55 41 33104661 [email protected]

Abstract Considering the possible expansion of palm plantations in the Amazon region, this study aims to assess the impact caused by changes in carbon stock due to change of land use in emissions of greenhouse gases inherent to the life cycle of palm biodiesel. To analyze this impact, the ecosystem carbon payback time (ECPT) was calculated as the number of years required to compensate for the carbon stock loss of the displaced ecosystem adding the annual avoided emissions due to the fossil fuel displaced by palm biodiesel, using a calculation method adapted from literature, supplied by spatial data of carbon stock change and data of carbon emissions in diesel and palm biodiesel life cycle from literature, put together by a geographic information system (GIS). The result is a map of different ECPT values to each different place on the Amazon Biome, depending on the natural soil and biomass types and also on the current land use. In areas where there are natural ecosystems, the ECPT can reach 79 years. However, ECPT can be considered null in areas occupied by crops and pastures in the current land use, where carbon stock changes are actually positive due to palm plantations establishment. The results suggest that land use can influence the trend of carbon emissions in biodiesel life cycle and therefore they show how important it is to consider these carbon losses during land conversion when studying the sustainability of biodiesel production, when GIS is a potential and meaningful tool. Key words: ecosystem carbon payback time, oil palm, Brazilian Amazon, land use change, carbon stock change.

Introduction Food, fuel and energy demand increase in addition to the escalating price of petroleum and adverse effects of using non-renewable sources have lead to a worldwide interest on the use of renewable sources for generating energy (Oliveira et al. 2008; Scharlemann and Laurance 2008; Suarez and Meneghetti 2007). Brazil‘s location, climate and land availability for bioenergy production are seen as advantageous factors for the country's economy. After the success of ethanol, there has been renewed interest in biodiesel production. Biodiesel are industrialized vegetable oils used as diesel fuel. Its combustion has been considered less polluting than the conventional diesel in terms of sulfur content, flash point, aromatic content and biodegradability (Ma and Hanna 1999), being able to reduce CO2 and sulfur levels in the atmosphere. Furthermore, biodiesel production has a renewable nature, promoting energy security,


and its use could be beneath also for the local rural population, job creation, provision of modern energy carriers to rural communities, and urban migration avoidance (Demirbas 2007). In Brazil, biodiesel is produced mainly from soybeans, animal fat, palm fruit, sunflower and cotton. From those, palm fruit has an advantageous oil yield (MAPA 2010)and provides a promising product for national use and exportation. Despite these characteristics, nowadays Brazil holds only a small share of world production and most of the palm oil needed for domestic industry is being imported (MAPA 2010). The low supply is related to several factors, as the access for agricultural technology, the need to guarantee social conditions and the environmentally sustainable use of the natural heritage, especially considering that much of the suitable area for palm cultivation is in the Amazon biome. In terms of environmental suitability, the avoided emissions by the use of palm biodiesel replacing conventional diesel can reach 3.14 kg CO 2eq/kg biodiesel (MME and EPE 2007). However, whether biofuels offer carbon savings depends on how and where they are produced. Converting rainforests to produce food crop–based biofuels in Brazil creates a ―biofuel carbon debt‖ by releasing 17-420 times more CO2 than the annual GHG reductions that these biofuels would provide by displacing fossil fuels, and the carbon debts attributed to biofuels would not be repaid by the annual carbon repayments from biofuel production for decades or centuries (Fargione et al. 2008). Additionally, biofuel production can displace crops or pasture from current agricultural lands, indirectly causing GHG emissions via conversion of native habitat to cropland elsewhere (Searchinger et al. 2008). Therefore, considering the suitability of the country and the deficit in the demand supply, attention has to be given to the possible expansion of palm plantations in the Amazon region. Hence, considering the environmental risks related to this expansion, this study aims to assess the impact caused by changes in carbon stock due to change of land use in emissions of greenhouse gases inherent to the life cycle of palm biodiesel. The assessment serves as a screening tool to optimize land use planning on a regional level, focusing in the Amazon region, despite it has to be linked with other sustainability criteria. The maps can be used for other researchers in future studies, for policy makers in strategic planning and for environmentally conscious investors in decision making, besides the usefulness for public awareness.

Methods During the life cycle of biodiesel or diesel (from extraction of natural resources till the final disposal), there are carbon intakes or emissions, contributing, positively or negatively to climate change. The biodiesel carbon emissions from land preparation (excluding land transformation) to the use phase can be compared to the emissions of diesel from oil extraction till its combustion. In this case, the carbon payback time consists on the time needed to compensate the amount of carbon that is emitted from land transformation, that is, the benefit of not using fossil fuels. The Ecosystem carbon payback time (ECPT) - adapted from Gibbs et al. ( 2008)- is calculated as in Equation 1. In the case where the land transformation does not cause increase in carbon emission (for instance, the transformation from pasture or cropland to palm tree cultivation), this calculation was not performed and ECPT is considered as nule. Therefore: tC

ECPT [year] =

GHG diesel

│∆CS │ h a tC −GHG biodiesel

h a x year

tC h a x year

[1]

Where │∆CS│ is the carbon stock change in biomass and soil due to land use conversion to palm plantation, which depends on the previous land use (natural ecosystem, cropland, pastureland or reforestation) taken from Lange (2012), GHGdiesel are the carbon emissions in the diesel life cycle and GHGbiodiesel are the carbon emissions in the biodiesel life cycle, excluding the emissions due to land transformation. GHGbiodiesel is taken from literature and GHGdiesel is calculated using the formula (Equation 2): GHGdiesel

tC ha .yr

= GHGdiesel

kg C kg diesel

×

EI biodiesel EI diesel

MJ kg biodiesel MJ kg diesel

× Ybiodiesel

kg biodiesel ha .yr

× 0,001 [2]


Where EIbiodiesel and EIdiesel are the energy intensities of biodiesel and diesel, respectively, and Ybiodiesel is the yield of biodiesel production. The values for ECPT were then added to the areas in the carbon stock change map due to palm plantations in the Brazilian Legal Amazon from Lange (2012)and a map was created representing the carbon debt due to diesel replacement by palm biodiesel and the consequent palm cultivation expansion.

Results and discussion For calculating the Ecosystem carbon payback times, variable values described in table 1 were used. Table 1 – Variable values used for calculation of ecosystem payback times Variable

Value

Source

Carbon emission in diesel life cycle

1,06 kg C/kg diesel

Souza et al. (2010), based on IPCC (2006) and EUCAR

(GHGdiesel )

(2006) Energy intensity of biodiesel

37,13 MJ/kg

Souza et al. (2010)

Energy intensity of diesel (EIdiesel )

54,10 MJ/kg

Souza et al. (2010)

Yield of biodiesel production

3963 kg/ha yr

Fresh Fruit Bunches yield =

(EIbiodiesel )

20,35 kg/ha.yr(Schmidt 2007);

(Ybiodiesel )

Palm oil rate in Fresh Fruit Bunches = 20-21% (EMBRAPA and MAPA 2000); Conversion rate from crude palm oil to palm oil used as biodiesel = 0,95 (Souza et al. 2010) Carbon emission in biodiesel life cycle

1436,51 kg CO2eq/ha

Based on a study of

(GHGbiodiesel )

yr

greenhouse gas emissions in palm oil biofuel life cycle (Souza et al. 2010)

The study from Souza et al. (2010) does not consider emissions from land use change, but includes emissions from other stages of the agricultural phase (application of fertilizers and pesticides and harvest), transportation (diesel), industrial phase (oil extraction and transesterification) and the use of fuel (burning) utilized for each hectare of palm oil. Emissions of different GHGs are considered based on the global warming potential (GWP) for 100 years (IPCC 2001). For the industrial phase, in which palm oil is extracted and biodiesel is produced, GHG emissions correspond to chemicals, electricity from the grid, and diesel for start-up of the turbines. Other GHG emissions are nonexistent because all energy inputs are supplied by co-products from palm oil processing. Emissions due to the manufacturing of equipment and construction of the facilities were not considered. To quantify emissions due to fossil fuels consumption, the production and use phases were considered. The map with the numbers of years required for avoided diesel emissions from substitution for biodiesel to compensate for losses in ecosystem carbon stocks during land conversion is shown in Figure 1.


Figure 1 – Ecosystem carbon payback times (years) The green areas where the carbon stock change would be nule or positive represent around 30% of the biome. In other areas, nevertheless, where there were former natural ecosystems, the carbon payback time can arrive to 79 years. Consequently, in these extreme cases, up to the year 79 planting biodiesel would be a net source of GHG and only from the 80th year on replacing biodiesel would result in reduction in carbon emissions. These results show how carbon stock change due to land transformation can influence the carbon emission trends in biodiesel life cycle and how important is considering this losses during land conversion when comparing biodiesel and petrodiesel life cycle emissions.

Conclusions The results suggest that, from the carbon stock point of view, palm cultivation should be expanded to areas that were already deforested, especially degraded pastures or non-productive croplands, and expansion to natural areas should be avoided or if it‘s necessary it should be done in the areas that house forests which are less capable to store carbon. This would help reducing the carbon emissions in biodiesel life cycle, which can be very high in cultivation expansions leading to natural areas, with carbon payback times reaching until 79 years, as the carbon losses during land conversion take years to be compensated by the avoided fossil fuel emissions from due to the use of biofuels. It is important, however, to take into account that indirect impacts of land use are not being considered in this study and they can considerably compromise the emission economy provided by biofuels. Thus, future studies should investigate also these indirect impacts so that decisions could base in a more holistic analysis. Additionally, the study outcome shows that GIS is a potential tool to be used for carbon stock change investigations when delineating scenarios of cultivation expansion to help the decision making demanded for the increasing biofuels production. The assessment serves as a screening


tool to optimize land use planning on a regional level, focusing in the Amazon region. However, it looks to the problem from a particular perspective, needing to be accompanied by other methods that encompass different perspectives to provide a reliable basis for decision making.

Ackowledgements We would like to thank to the Brazilian Coordination of Improvement of Higher Education Personnel (CAPES)for the master scholarship provided, to the Swiss Federal Laboratories for Material Science and Technology (EMPA) and the Federal Technological University of Paraná (UTFPR), and especially to the Graduate Program in Mechanical and Materials Engineering (PPGEM), for the infrastructure and scientific and technical support provided.

References Demirbas A (2007) Progress and recent trends in biofuels. Progress in Energy and Combustion Science 33 (1):1-18 EMBRAPA, MAPA (2000) A cultura do dendezeiro na Amazônia Brasileira [Palm oil cultivation in the Brazilian Amazon]. Embrapa Amazônia Ocidental, Embrapa Amazônia Oriental, Ministério da Agricultura, Pecuária e Abastecimento, Belém, Manaus EUCAR (2006) Well-to-wheels analysis of future automotive fuels and powertrains in the European context. CONCAWE and JRC/IES, Fargione J, Hill J, Tilman D, Polasky S, Hawthorne P (2008) Land clearing and the biofuel carbon debt. Science 319:1235-1238 Gibbs HK, Johnston M, Foley JA, Zaks D ( 2008) Carbon payback times for crop-based biofuel expansion in the tropics: the effects of changing yield and technology. Environmental Research Letters 3 (3):3-10. doi:10.1088/1748-9326/3/3/034001 IPCC (2001) Third Assessment Report of the Integovernmental Panel on Climate Change. Intergovernmental Panel on Climate Change, New York IPCC (2006) IPCC guidelines for national greenhouse gas inventories. Intergovernmental Panel on Climate Change, Hayama Lange M (2012) A mudança de estoque de carbono por transformação da terra e seu uso no Inventário de Ciclo de Vida de produtos de origem renovável: estudo de caso da possível expansão da palma de óleo na Amazônia Legal brasileira. Universidade Tecnológica Federal do Paraná Curitiba Ma F, Hanna MA (1999) Biodiesel production: a review. Bioresource Technology 70 (1):1-15 MAPA (2010) Palma de óleo: Programa de Produção Sustentável. Ministério de Agricultura, Pecuária e Abastecimento, MME, EPE (2007) Potencial de redução de emissões de CO2 em projetos de produção e uso de biocombustíveis [Reduction potential for CO2 emissions in biofuels production and use projects]. Ministério de Minas e Energia, Empresa de Pesquisa Energética, Oliveira FCC, Suarez PAZ, Santos WLP (2008) Biodiesel: Possibilidades e Desafios [Biodiesel: Possibilities and Challenges]. Química Nova na Escola 28 Scharlemann JPW, Laurance WF (2008) How Green Are Biofuels? . Science 319 (5859):43-44 Schmidt JH (2007) Life cycle assessment of rapeseed oil and palm oil. Ph.D, Aalborg University, Aalborg Searchinger T, Heimlich R, Houghton RA, Dong F, Elobeid A, Fabiosa J (2008) Use of U.S.uso agrícolas for biofuels increases green house gases through emissions from land use change. Science 319:1238-1240 Souza SP, Pacca S, de Ávila MT, Borges JLB (2010) Greenhouse gas emissions and energy balance of palm oil biofuel. Renewable Energy 35 (11):2552-2561 Suarez PAZ, Meneghetti SMP (2007) 70º aniversário do biodiesel em 2007: evolução histórica e situação atual no Brasil [70th anniversary of biodiesel in 2007: historical development and current situation in Brazil]. Química Nova 30:2068


Life cycle impact assessment of cotton production in the Brazilian Savanna Ana Cristina Guimarães Donke* – Letícia De Santi Barrantes1 – Michelle Tereza Scachetti1 – Nelson Dias Suassuna2 - Maria Clea Brito de Figueirêdo3 –Luiz Kulay4 – Marília Ieda da Silveira Folegatti Matsuura1 *1Embrapa Meio Ambiente, Rod. SP 340, Km 127,5, CP 69, 13820-000, Jaguariúna, SP, Brasil; 2Embrapa Algodão; 3Embrapa Agroindústria Tropical; 4Escola Politécnica da Universidade de São Paulo

++55 19 33112731 [email protected] URL: http://www.cnpma.embrapa.br

Abstract Cotton is a product of great economic importance for Brazil – the world's fourth largest producer and fifth largest exporter of this fiber. Cotton cultivation is in full expansion; the current area planted with the crop occupies 1.38 million hectares, of which 99% is in the Savanna biome. In the 2010/2011 harvest, 2.0 million tons of cotton plume were produced for the textile industry and 5.2 million tons of seed were used for oil extraction. Cotton linter is a residue from the oil production, whose use is being studied in the production of cellulose nanoparticles within the Agronano research project of Embrapa. The physical properties of nanomaterials - reduced size, varied shape and high surface area - can cause harmful effects to living organisms, requiring evaluation in relation to their potential impacts on the environment and human health. The assessments started after preparing the life cycle inventory of the agricultural cotton production phase, according to the statements of ISO standards 14040 and 14044. The production system studied employed no-tillage and was used in rotation with millet - one of the most commonly used system for the cultivation of cotton in the Brazilian Savanna. Cotton is a highly demanding crop with respect to inputs such as chemical fertilizers and pesticides. Cultivation carried out according to the technical recommendations for this crop employs over 43 different pesticides, including products for seed treatment, herbicides, insecticides, fungicides, growth regulators and maturation agents. The agricultural use of these products, particularly the fertilizers – which are carriers of heavy metals –, as well as their production, can generate severe impacts, mainly in the categories related to Toxicity and Eutrophication. Cotton production is the process responsible for the main emissions and impacts among all processes considered in this study. Rationalization of the use of agricultural inputs is clearly the way to reduce the environmental impact caused by cotton production. Other agricultural production systems, as also the fiber extraction and the production of nanofibers, will be assessed following the conclusion of this work. Keywords:

LCI,

production

system,

agricultural

input,

fertilizer,

pesticide,

Toxicity,

Eutrophication 189


1 Introduction Brazil is currently the World‘s fourth largest producer and fifth largest exporter of cotton and its derivatives. The Brazilian cotton crop has been growing vertiginously due to production modernization and favorable environmental conditions in the country. In the 2010/2011 harvest, the area cultivated increased by 551,000 ha, signifying an increase of 65.9%. Currently it occupies 1.38 million hectares as against 836,000 ha planted in 2009/2010. According to the National Supplies Company, 2.0 million tons of cotton plume were produced in the 2010/2011 harvest – a production 70% higher than in the previous harvest; seed productivity reached 3762 kg/ha – 3.5% greater than the performance registered in the previous period; and the productivity in fiber reached 1490 kg/ha – slightly greater than the maximum yield of 1487 kg/ha registered in 2007/2008 (Anuário Agrícola do Algodão 2011; Conab 2011). Such an important expansion in area and production results in impacts of various natures, the emission of greenhouse gases (GHG), derived from the land use change (LUC), being particularly important, and regional outreach impacts also deserve attention. The cotton plant presents some particularities and vulnerabilities, such as the production of nectar, which makes it very attractive to insects, amongst which the cotton boll weevil (Anthonomus grandis) stands out, a pest which is difficult to control. It also shows some particular metabolic characteristics and leaf architecture, which make it sensitive to interference by weeds (Beltrão 2003; Fonseca et al. 2011). In order to combat the pests and diseases, the cotton producers apply a battery of various insecticides, fungicides and herbicides. These, together with the products used in the treatment of the seeds, desiccant herbicides, growth regulators and maturing agents, can add up to more than 50 assets applied in the productive cycle, with a high potential for ecotoxicity and human toxicity impacts. Cotton linter is an important co-product of cotton fibers; it corresponds to about 12.5% of the total composition of the cotton seed and consists of short fibers, containing more than 90% cellulose. Of the various applications of cotton linter, the production of hydrophyllic cotton wool, surgical tissue, mixed tissues and cellulose stand out ought to be highlighted. The project ―Nanotechnology applied to agribusiness‖ (AgroNano), developed by the Brazilian Agricultural Research Company (Embrapa) has carried out research into the use of cotton linter in the production of cellulose nanostructures. The interactions between these nanostructures and living organisms are still not fully understood, and toxicological studies have indicated the occurrence of noxious effects on microorganisms, algae, fish, rats and human cells (Paschoalino et al. 2009). However, the preliminary results of in vivo toxicological studies performed with cellulose nanostructures obtained from coconut, cotton and sugarcane, found no toxicity in these materials. The commercial use of nanomaterials could promote their dissemination into different environmental compartments and hence any risks related to their presence must be evaluated throughout their entire life cycle: from the production of the raw material (cotton), until the production of the nanofibers themselves. The objective of the present study was to evaluate the 190


environmental performance at the cotton production phase using the Life Cycle Assessment approach. This analysis allowed for the orientation and adjustment of the new technology, still under development, to the environmental requirements. Other agricultural production systems, as also the fiber extraction and nanofiber production, will be evaluated in sequence to the present work.

2 Methodology 2.1 Definition of the Goal and Scope

The methodology used in this study was based on the technical requirements of the ISO 14044 standard. The Objective of the study was ―to assess the environmental performance of the agricultural production phase in which the cotton boll destined for fiber production is obtained. Co-products, such as seeds and cotton linter, are also produced. Cotton linter is used in the production of cellulose nanostructures – our final product‖. The following Scope definition statements were adhered to: Product system: agricultural production of cotton. Function: to produce cotton destined for the production of cellulose nanostructures. Reference flow: production of 1 ton of cotton boll. System boundaries: the system studied encompassed the production of cotton (boll), agricultural inputs, diesel, and electrical energy. Life Cycle Impact Assessment (LCIA) method and impact categories: ReCiPe Midpoint H. There were considered all the impact categories from the method except Marine Ecotoxicity. Data quality requirements: Temporal dimension - 2011/2012 harvest; Geographic dimension Brazilian Savanna; and Technological dimension - no-tillage system in rotation with millet, nonirrigated – the most representative system used in Brazil. Regarding to Data source, primary data were used for the agricultural production; and secondary data – technical and scientific literature, consulting specialists, and the Ecoinvent database – were considered for the other processes. Allocation: no allocation were carried out to the study.

2.2 Elaboration of the LCI

Considering the cotton crop expansion in Brazil, the study evaluated two possible scenarios: 1) the substitution of native wasteland (of the Savanna) for the cultivation of cotton (worst scenario); and 2) the substitution of another annual crop by cotton (best scenario). The carbon stock data for the living biomass, the dead organic matter and the soil type were obtained from the ―Second Brazilian Inventory of Greenhouse Gas Emission and Anthropic Removal‖ (MCT 2010); the carbon dioxide (CO2) emissions derived from LUC were estimated using the IPCC method (2006). Atmospheric emission of CO2 due to the use of lime; of CO 2 and ammonia (NH3) from the use of urea; of nitrous oxide (N2O) generated by the use of nitrogenous fertilizers and crop residues; and the nitrate (NO3) flows to groundwater, also resulting from the use of nitrogenous fertilizers, were 191


all calculated according to the IPCC guides (2006). On the other hand, estimations of the atmospheric emissions of methane (CH4), due to the reduction in soil retention capacity caused by the use of nitrogenous fertilizers; of nitrogen oxides (NOx), corresponding to a fraction of the N2O emissions; and of the flow of heavy metals originating in the fertilizers to surface waters, were made according to Canals (2003). The direct emissions of nitric oxide (NO) from the use of nitrogenous fertilizers; the phosphate (PO4) losses to groundwater and to the soil due to the use of phosphate fertilizers; and the heavy metals originating in the fertilizers to surface waters and the soil, were estimated according to Schmidt (2007). Since cotton is a crop involving an intense use of pesticides, special attention was dedicated to the emissions resulting from this use. The fate analysis was used to estimate the distribution of these pesticides in the environmental compartments, according to the model suggested by Haushild (2000), modified by Haushild & Birkved (2002) and by Canals (2003), assuming some premises: The pesticides used to treat the seeds, applied in a closed equipment, and the herbicides used in the plant pre-emergence phase and applied directly to the soil, did not drift due to the wind, nor were they retained by the plant. For all the pesticides, of the total amount of each product applied, only that applied to the border area of the plantation (22.6% of the total area) was affected by drift. An emission factor of 3.5% due to drift was adopted, recognizing cotton as a crop of low stature (Canals 2003). The retention factor of the pesticides by the plants was obtained from Linders et al. (2000), considering the chronogram of applications of a standard farm and the phenological stage of the plants. The chronogram of applications was also used to estimate the fraction of pesticide degraded in the soil, which is a function of the number of days passed between application of the product and harvest. The daily rates of loss by evaporation from the plant and from the soil adopted were those cited by Canals (2003). The physical and chemical characteristics of the pesticides were obtained from the ―Pesticide Properties Database‖ (PPDB). The physical and chemical characteristics of the soil used to calculate leaching were those indicated by Paraiba et al. (2003), and corresponded to the most common type of soil in the region. Emissions generated by the burning of diesel oil were calculated based on Nemecek & Kagi (2007). The times spent on each operation were obtained from the standard farm, with the exception of fertilization, for which information from Ecoinvent database was used.

3 Results and Discussion LCI for the agricultural phase of the cotton production covered 214 environmental aspects. It included the consumption of seeds, lime, six types of fertilizer and 43 types of pesticide, apart from the diesel oil used in the agricultural operations (Table 1). In all, 171 output flows of substances from the productive system to the environmental compartments were estimated, the 192


majority derived from the use of pesticides. Data from Table 1 indicates that most expressive impact were those of Terrestrial and Freshwater Ecotoxicity. The same result was also found recently by Silva et al. (2012). The extremely high fertilizer and pesticide consumptions resulted in impacts related to Human Toxicity and Terrestrial and Aquatic Ecotoxicity. The agricultural production was indeed the main process contributing to the first two impacts, being responsible for 95.8% and 99.3%, respectively. For Human Toxicity the heavy metals present in these agrochemicals were the most important toxic substances; in terms of Aquatic Ecotoxicity the pyrethroid insecticides must to be highlighted.

Table 1: Natural resources, inputs from and outputs on the technosphere, for 1 ton of cotton Known outputs to technosphere Cotton production, kg

1.00E+03

Known inputs from nature ( resources) Occupation, ha

2.78E-01

Transformation of, ha

2.78E-01

Transformation to, ha

2.78E-01

Known inputs from technosphere Seeds, kg

8.67E+00

Lime and gypsum, kg

5.88E+02

Urea, kg

3.93E+01

Triple superphosphate, kg

8.13E+01

Potassium chloride, kg

5.99E-02

Zinc sulfate, kg

2.78E+00

Borax, kg

5.05E+00

Ammonium sulfate, kg

5.56E+01

Insecticides (24 products), kg

8.84E+00

Fungicides (5 products), kg

6.75E-01

Glyphosate, kg

1.00E+00

Diuron 500 SC, kg

1.50E+00

Other herbicides (6 products), kg

2.42E+00

Growth regulators (4 products), kg

1.12E+02

Diesel oil, kg

4.67E+01

Regarding to Aquatic Toxicity, in addition to the cotton production, the production processes of the growth regulators, insecticides and herbicides also contributed. For this category the substances showing the greatest impact were again that one from the pyrethroid group. The cotton production process, together with the production of the phosphate fertilizers and the growth regulators, generated contaminants responsible for the Aquatic Eutrophication impact. Evidently, the inventories of the cotton produced in the two different LUC scenarios varied with 193


respect to the area of natural vegetation altered and also with respect to the amount of GHG emissions. In the scenario in which the native vegetation was substituted by cotton, 0.286 m 2 of area were altered and 78.9 ton CO2-eq/ ton cotton were emitted. In the scenario which predicted the installation of the cotton crop in an area previously dedicated to another annual crop, the emissions corresponded to 4.1 ton CO2-eq/ton cotton. The actual cotton production was the process that most contributed to the Climate Change impact. The CO 2 emitted as a function of LUC, when this occurred (in the worst scenario) and the N 2O emissions from nitrogen fertilization were the main GHG emitted.

4 Conclusions Cotton production is the process responsible for the main emissions and impacts among all processes considered in this study. An improvement in the environmental performance of cotton production depends on rationalization of the use of agrochemicals, particularly the pesticides. Even if the fragility of the cotton crop limits the adoption of alternative methods for pest control, the chemical control should be optimized, including opting for the use of more selective and safer molecules. Embrapa recommends Integrated Pest Management, which consists of monitoring the insect-pest populations in order to orientate pesticide applications, which should occur using only the truly necessary pesticides, using an adequate amount at the correct point in time (when the insect density starts offering a risk to the crop, although still below the level of causing economic damage). This allows for an association of the chemical and biological methods and a reduction in the use of pesticides. With respect to the Climate Change impact caused by emissions generated by the LUC, this presents the challenge of finding an equilibrium between an increment in productivity, which signifies an increase in production without increasing the area, and a reduction in the use of chemical inputs. Acknowledgements The authors are gratefully acknowledged to Embrapa, by financial support to the project AgroNano, and to Jatropt project, by the methodological support for the construction of the ICV

References Bastos CS, Torres JB (2005) Controle biológico e o manejo de pragas do algodoeiro. Embrapa Algodão, Campina Grande. Beltrão NEM (2003) Controle de plantas daninhas na cultura do algodão. In: Anais do IV Congresso

Brasileiro

de

Algodão.

http://www.cnpa.embrapa.br/produtos/algodao/publicacoes/trabalhos_cba4/395.pdf. Accessed 23 194


october 2012 Canals LM (2003) Contributions to LCA methodology for agricultural systems. Site dependency and soil-degradation impact assessment.

Tesis de doctorado, Universidade Autônoma de

Barcelona Czepak C, Fernandes PM, Albernaz, KC et al (2005) Seletividade de inseticidas ao complexo de inimigos naturais na cultura do algodão (Gossypium hirsutum L.) Pesqu. Agropec. Tropical 35:123-127 INDEA-MT (2012) Programa de Prevenção e Controle do Bicudo-do-algodoeiro no estado de Mato Grosso. http://www.indea.mt.gov.br/html/internas.php?tabela=paginas&codigoPagina=14. Accessed 20 october 2012 IPCC (2006) N2O emissions from managed soils, and CO2 emissions from lime and urea application. In: IPCC. Guidelines for national greenhouse gas inventories. Agriculture, forestry and other land use. IPCC, Geneva Linders J, Mensink H, Stephenson G et al (2000) Foliar interception and retention values after pesticide application. a proposal for standardized values for environmental risk assessment (Technical Report). Pure Appl. Chem. 72:2199–2218 Ministério da Ciência e Tecnologia – Brasil (2010) Segundo inventário brasileiro de emissões e remoções antrópicas de gases de efeito estufa. Relatórios de referência. Ministério da Ciência e Tecnologia, Brasília Paraíba LC, Cerdeira AL, Silva EF et al (2003) Evaluation of soil temperature effect on herbicide leaching potential into groundwater in the Brazilian Cerrado. Chemosphere 53:1087–1095 Paschoalino MP, Marcone, GPS, Jardim WF (2010) Os nanomateriais e a questão ambiental. Química Nova 33:421-430 Reetz RR, Vencaro AZ, Kist BB (2011) Anuário brasileiro do algodão. Gazeta, Santa Cruz do Sul Schmidt JH (2007) Life cycle assessment of rapeseed oil and palm oil. Thesis, Aalborg University Silva TL, Barbosa PP, Angelis Neto G (2012) Impactos ambientais da cadeia têxtil do algodão por meio da avaliação do ciclo de vida. In: Anais do III Congresso Brasileiro em Gestão do Ciclo de Vida de Produtos e Serviços. Universidade Federal de Santa Catarina, Florianópolis

195


Anthropogenic phosphorus emissions inventory in China Qinqin Chen, Zengwei Yuan Miss. Qinqin Chen State Key Laboratory of Pollution Control and Resources Reuse School of the Environment, Nanjing University Nanjing 210023, P.R. China

[email protected] Phone: 86-25-18260086730

Corresponding author: Prof. Zengwei Yuan State Key Laboratory of Pollution Control and Resources Reuse School of the Environment, Nanjing University Nanjing 210023, P.R. China

[email protected] Tel and Fax: 86-25-89680532

Abstract Phosphorus (P) is a key factor in aquatic eutrophication which has become a worldwide environmental issue. Many developing countries including China have made great effort in this anti-phosphorous-contamination battle. In this article we developed a general phosphorus emissions inventory within socioeconomic system, including 22 industries and concerning about the production and use of hundreds of products. Furthermore, considering the contribution of phosphorous emissions to eutrophication of lakes, we quantified the phosphorous emissions inventory in Wuwei, a typical county in China. The results show that Wuwei County released 3,578 metric tons (tonnes) of phosphorous into the local aquatic environment in 2008 and the phosphorus load(3.35 kg-P/cap/yr or 19.43 kg-P/ha/yr ) was higher than those of the adjoined counties in Chaohu watershed. The agricultural subsystem discharged the largest quantity of phosphorus (2,572 tonnes), meanwhile, had a relatively low phosphorus waste recycling rate (36%). Besides, the rural residential and small-scale livestock breeding also accounted for substantial portions of phosphorous emissions. Based on the above results, we provided suggestions on phosphorous emissions mitigation of agricultural cultivation, rural residential consumption, and livestock breeding, as well as discussion on their feasibilities. 196


Keywords: phosphorus; industrial metabolism; life cycle inventory; industrial ecology; environmental management.

Introduction Phosphorus (P) is a strategic resource in the agricultural and chemical industries and a key element in eutrophication that has attracted increasing global attention. About 37 million metric tons (tonnes) of P are in global circulation annually, of which 22 million tonnes are contributed by mining activities (Vaccari et al. 2009). High extraction and low use efficiency lead to great loss and P contamination has recently become a prevalent problem in many countries. Governments and communities have attempted to resolve this problem using many approaches, however, most of which have achieved limited results due to an incomplete understanding of P emissions inventory.

China has 2,859 rural counties with 721 million residents and 333 cities with 607 million residents in 2008 (NBSC 2009). Rapid growth of industrial economy, lack of environmental infrastructure, and inefficient implementation of environmental regulations make it difficult to resolve P emissions and correspondent eutrophication. The environmental statistics yearbook 2008 showed that 57.4% of Chinese sewage was treated in 2008 (MEP 2008), and this rate was much lower in rural areas. Large quantities of untreated wastewater containing P have been dumped into local aquatic environments, potentially leading to a series of environmental and ecological issues. The percentage of eutrophicated lakes in China has increased sharply from 41% in the 1970s to 77% in the late 1990s (Jin 2008). Thus, the influence of counties surrounding these water bodies cannot be ignored in China.

Aiming at mitigating eutrophication of lakes, a complete inventory in watersheds is very important because it can help macroscopically understand the sources of P emissions and their spatial distributions. Much effort has been done on the source tracing and transforming/transportation process mechanism of P emissions (Church, Ducklow et al. 2002; Ganeshram, Pedersen et al. 2002; Aurousseau and Institut 2003). However, there is no complete anthropogenic P emissions inventory so far, especially for eutrophication mitigation. In this article, we try to develop a life cycle phosphorus emissions inventory and use it in a typical county in China, aiming at quantifying the contributions of different human activities to P emissions and eutrophication.

Materials and Methods P emissions inventory in socioeconomic systems

P is widespread in soil, atmosphere and aquatic environment. It exist in soil mainly in three forms 197


which are phosphorite with the highest P concentration, companion minerals with low P content where the P couldn‘t be effectively used, and the traces of P which can be absorbed by plants. In aquatic environment P mainly exist in water body and aquatic organisms. In atmosphere environment, P is mainly attached on the surface of dust floating in the air and finally settling down to the earth.

When P enters in anthoposphere, it will be gradually discharged to the environment during the manufacturing and consuming processes. So the socioeconomic system can be simply categorized into three subsystems, namely P-containing final products manufacturing, P-containing final products consumption and waste treatments (shown in figure 1). There are three industries in the manufacturing subsystem which cause P emissions, consisting of mining industry, manufacturing industry and farming, forest, livestock breeding and fishery industry. Based on the P-containing manufacturing industry inventory, the consumption or use inventory of P-containing activities can be easy figured out. All the waste generated from the previous two processes will either be treated in the waste treatment process, or emissions in to the nature environment directly.

Atmosphere environment

P-containing final products manufacturing (Manufacturing industry inventory)

Phosphor us in other minerals

Phosphor us in soil

Socioeconomic System

Soil environment

Phosphorit e

P-containing final products consumption (Consumption inventory)

Manufacturing industry

Residents living consumption

Farming, forest, livestock breeding and fishery industry

Government consumption

Mining industry

WT WT

Aquatic environment Phosphorus flow

WT

Phosphorus in aquatic organisms Waste treatment process

Figure 9 Framework of Phosphorus inventory

Mining industry inventory Since the time and energy are limited, only those bulks of consuming goods were taken into consideration. They are: 

Phosphorite mining industry 198




Coal mining industry



Petroleum industry

Manufacturing industry inventory Based on the literatures (Bolster, Vadas et al. 2012; Han, Yu et al. 2013; NBSC 2011), the P emission industries can be categorized as: 

Phosphate fertilizer manufacturing



Coal processing



Pharmaceutical manufacturing



Feed processing



Soap and synthetic detergent manufacturing



Metal casting, forging processing, especially for ferrous metals



Building materials manufacturing



Coatings, inks, paints and similar products manufacturing



Cotton, chemical fiber textile and printing and dyeing finishing



Agricultural and sideline products processing industry, including vegetable oil processing, livestock and poultry slaughter, etc.



Food production



Sewage treatment and recycling



Refractory products manufacturing



Daily chemical industry and special equipment manufacturing



Weapons and ammunition manufacturing

Farming, forest, livestock breeding and fishery industry inventory Based on the literatures (Li, Bai et al. 2012; Linderholm, Tillman etal. 2012; Nesme, Toublant et al. 2012), activities with P emissions in this subsystem can be categorized into: 

Farming industry, including the planting of corn, potato, oil plants, beans, cotton, hemp, sugar, tobacco, tea, Chinese herbs, fruit, vegetables, nuts, etc.



Forest industry, including the logging of economic forest, bamboo, etc



Fishery industry, including the marine culture, marine fishing, inland culture, inland fishing, etc.



Livestock breeding industry, including the husbandry of poultry, livestock, etc.

P-containing products consumption/use activities According to the manufacturing industry inventory, the final P-containing goods used in consumption and production activities can be listed as follow: 

Final products used for dairy life of residents including coals, medicines, food (grain, vegetable oil, aquatic products, vegetable, fruit, nut, meat products), cloth, furniture, buildings, dyeing and printing materials, daily chemical products, etc.



Final products used for national and local government including the consumption of 199


refractory products, weapons and ammunition.

Description of Study Area Wuwei is a typical county in Anhui Province, located southeast of Chaohu Lake (Fig. 2). This lake was included in the ―Three Rivers and Three Lakes‖, a list of key targets for water-pollution control and prevention in China, because of its serious eutrophication problem. Wuwei County is 244,900 hectares in area, 35% of which is arable land. The county had 1,419,737 inhabitants in 2008, of which 175,113 were living in urban areas. The major recipients and suppliers of freshwater are Changjiang River and its tributary, the Yuxi River. Given its subtropical climate, the economic system of Wuwei County is dominated by agriculture, mainly producing rice, cotton, and rape. In 2008, the gross domestic product (GDP) of Wuwei County was ranked first among counties governed by Chaohu City, and the GDP per capita was 11,102 RMB Yuan.

Figure 2 Geographic location of Wuwei County.

System Definition This study mapped P emissions inventory of Wuwei County in 2008. Because Wuwei County has no natural phosphorite sources, so the P mining industry was absent in the inventory. The three processes were divided into nine subsystems, shown in table 1. Table 5 P emissions inventory of socioeconomic system in Wuwei County Processes

Inventories Manufacturing industry

Subsystems Pesticide manufacture, coal extraction

P-containing final products manufacturing

Farming, forest, livestock

Agriculture, domestic

breeding and fishery

livestock breeding, small-

industry

scale livestock breeding 200


P-containing final

Residents living

Urban residential, rural

products consumption

consumption

residential

P waste treatment

-

Wastewater treatment, solid waste treatment

Data Collection and Calculation Methods Data source The data used in this article were collected from governmental statistics, published reports, and field investigation. Most statistical data, such as population, material output, and product consumption, were collected from the Chaohu Statistical Yearbook in 2008 (BSCC 2009). Emission factors were collected from the published literatures data and field investigation.

The field investigation in Wuwei County included the site observation and residents questionnaire survey. Specifically, we had visited 3 villages, namely Tongcheng Village, Fandu Village and Shuangyu Village, which are all governed by Wuwei County. We had interviewed the managers and engineers of 16 relevant companies and officers of local government agencies. In addition, we distributed a hundred of questionnaires among the Wuwei residents. Finally we collected hundreds of first-hand data.

Basically the data of phosphorus intensity, which could not be directly obtained from the literatures, was acquired from the field survey, especially from the interview of the local professionals，while the data of local residents‘ consumption were obtained from the questionnaire. Besides, considering uncertainty of data derived from the field investigation, a cross-check was conducted to reduce stochastic errors. The survey data were compared with those of Lujiang County (Yuan et al. 2011), which is adjacent to Wuwei County and characterized by similar residential living patterns. Calculation Assumptions The anthropogenic P emissions are assumed to dominate the natural P emissions, so that natural P emissions (e.g., wind erosion of P mines, P release from soil, P purification in water) are not included in the analysis. Calculation Method The whole inventory calculations were fundamentally based on the equations (1) ~ (4):

EP  EPa  EPs  EPw ,

(1)

201


n

m

EPa   Q j  EF ij (1  Rij ) ,

(2)

i 1 j 1 n

m

EPs   Q j  EF ij (1  Rij ) ,

(3)

i 1 j 1 n

m

EPw   Q j  EF ij (1  Rij ) ,

(4)

i 1 j 1

Where EP represents the total P emissions from the socioeconomic system; EPa represents the total P emissions to atmosphere; EPs represents the total P emissions to soil; EPw represents the total P emissions to water (aquatic environment); i represents the P emissions sources; j represents the P-containing products;

Q j represents the output of the P-containing product j in a single year;

EFij represents the P emissions factor of the product j from the emission source i, usually given as a percentage of the unit weight of the product; Rij represents the recycle, reuse or reuse rate of the emitted P; n represents the total number of the emission sources in the inventory, and m represents the total number of products in a given emission source.

Results The overall P emissions inventory diagram was constructed by integrating the three processes of P manufacturing and production, consumption, and waste treatment (Fig. 3). Atmosphere environment P-containing final products consumption

Socioeconomic System

Soil environment

P-containing final products manufacturing

2611

Manufacturing industry Pesticide Manufacture

Coal Extraction

Residents living consumption 10.8

Rural residential

Urban residential

13

13

Farming, forest, livestock breeding and fishery industry Agriculture

Domestic Livestock Breeding

Smallscale Livestock Breeding

2572

22

291

1720

P Waste treatment Waste water treatment Solid waste treatment

422 66 20

70

5

598

Aquatic environment Phosphorus flow

Unit: tons-P/yr

Figure 3 The overall phosphorus emissions inventory in Wuwei County, 2008.

The total P input into the Wuwei County system was 10,504 tonnes, including 4,655 tonnes 202


recycled, and 3,578 tonnes discharged into aquatic environments. Table 2 shows the overall P activities for each process. Table 6 Phosphorus (P) activities in each process (tonnes-P/yr) P Processes

Input

Emissions

Recycle

P-containing final-products manufacturing

8,668

2,905

4,655

P-containing final-products consumption

1,765

668

0

P waste treatment

71

5

0

Obviously, P-containing final-products manufacturing process was the most active process in this P metabolism system, especially for the farming, forest, livestock breeding and fishery industry. In this industry, the P emissions were 2905 tonnes, which accounts for 81% of total P emissions in Wuwei County in 2008. Only part of urban P waste was treated, and the emissions quantity comprised only 1.90% of the total P emissions. Phosphorus Inventory of Manufacturing Industry

In the manufacturing industry inventory, only two industries were included, because Wuwei County has no Phosphorite reserves, all the phosphorus needed in manufacturing industry were coming from import, which partially restricted the local development of P manufacturing industry. Table 7 Inventory of manufacturing industry Products

Production

P content

P amount

P emission

name

kg/yr

%

kg/yr

kg/yr

Pesticide

Pesticide

349,000

3.30%

11,517

manufacture industry

Herbicide

20,000

7.70%

1,540

Anthracite

132,790,000

0.02%

26,558

Industry inventory

Coal extraction industry

20,000 0

Phosphorus Inventory of Farming, Forest, Livestock Breeding and Fishery Industry

Phosphorus inventory Agriculture subsystem In agriculture subsystem, the input inventory were all kinds of seeds, recycled manure from rural residents and livestock breeding, recycled straws, fertilizers and pesticides. All the recycle rates were calculate from the field investigation. And output inventory includes agriculture products and straws of paddy, wheat, rapeseed, peanut, sesame, seed cotton, vegetables and fruit, corn, beans and sweet potato. Finally 25.16% of P was discharged into ambient water through the farm drainage and 25.54% of P was deposited in soil. Table 8 Input and Output Inventory of Agriculture Subsystem Input inventory

P amount kg/yr

Output inventory

P amount kg/yr 203


Seeds

63,840

Agriculture products

3,536,717

Recycled straws

1,454,500

Straws

1,502,632

Recycled rural resident's manures

904790

Recycled small-scale livestock's

602949

manures Recycled domestic livestock's

1490421

manures Fertilizers

5,640,639

Pesticides

65,733

Phosphorus Inventory of Livestock Breeding Subsystems Small-scale livestock breeding have 7 kinds of livestock (chicken, duck, goose, pig, beef cattle, sheep, aquatic products), and they were fed with professional feed. While the domestic livestock breeding only have 5 livestock (chicken, duck, goose, pig, farm cattle), and they could only be fed on grass and kitchen wastes from rural residents. Finally, the P emissions of Small-scale livestock breeding subsystem were 291 tonnes, which were 13 times bigger than the domestic one (22 tonnes). Table 9 Input and Output Inventory of Livestock Breeding Subsystems P amount kg/yr Input inventory

Professional Feed Recycled kitchen wastes Grass

P amount kg/yr

Small-scale

Domestic

Output

Small-scale

Domestic

livestock

livestock

inventory

livestock

livestock

breeding

breeding

breeding

breeding

3,461,766

0

Living animals

2,314,527

147,285

0

3,991,619

Manures

1,810,659

1,496,707

0

257,651

Eggs

17,732

37,690

Milk

6,741

0

Phosphorus Inventory of Residential consumption

The living styles between urban and rural residents were quite different. Comparing to rural residents, the urban residents consumed various kinds of cleaning supplies and more meat per person. Due to the large population base, the rural residential subsystem have a higher P emissions of 598 tonnes, while urban residential subsystem only discharged 83 tonnes, among which 15 204


tonnes waste water were treated in waste treatment process. Table 10 Input and Output Inventory of Residential subsystems Amount of consumed P kg/yr Input Inventory Urban residents Agriculture

Paddy

1352144.83

products Wheat

36734.76

Cole

98550.14

Peanut

5343.79

Sesame

Meat

Rural residents

68763.29

1983.91

Cotton

1828.19

Vegetables

152.90

Corn

34622.57

Beans

1972.44

Sweet potato

6345.29

Pig

7457.42

22821.09

Cow

767.09

1023.17

Sheep

297.77

170.91

Poultry

2957.18

10972.27

Aquatic products

3259.01

15431.97

Fruit

Fruit

3967.92

8684.08

Milk

Milk

4920.29

7049.79

Eggs

Eggs

7089.23

23005.84

Cleaning supplies

Laundry soap

1.53

0.00

Liquid detergent

12.66

5.71

Detergent

62.54

313.76

Softener

5.51

0.00

Toilet Cleaner

28.77

0.00

Hand sanitizer

9.05

0.00

Coal

839.43

10049.46

Snacks

23176.15

0.00

Other

205


Discussion Products’ phosphorus emissions rate

Where is the production where is the emissions, so the emissions rate of unit products can be used to reflect the P utilization efficiency during the production process.

E

D O

(5)

E represents the emissions rate of unit products, kg-P/kg(cap), D represents the total amount of P emissions (including the P emissions to water, atmosphere and soil) during the manufacturing or cultivating of products; O represents the total output of the products, kg or capital. According to the equation (5), the main products‘ emissions rate can be obtained. Subsystems

Agriculture

Domestic livestock breeding

Small-scale livestock breeding

Products output

Total P emissions

kg-

kg(cap)

kg/yr

P/(kg(cap).yr)

1,122,003,000 kg

5,183,522

0.0046

Chicken

3,651,788 cap

9,079

0.0025

Duck

1,280,415 cap

3,726

0.0029

Goose

698,763 cap

2,108

0.0030

Pig

94,799 cap

6,959

0.0734

Farm cattle

11,287 cap

476

0.0422

Pig

151,765 cap

9,599

0.0633

Beef cattle

19,075 cap

7,082

0.3713

Sheep

8,313 cap

320

0.0385

Chicken

4,518,212 cap

8,076

0.0018

Duck

3,359,585 cap

6,005

0.0018

Goose

1,621,237 cap

2,898

0.0018

55,066,000 kg

257,434

0.0047

Products Agriculture products

Aquatic products (kg)

The analysis results show that the cultivation of unit agriculture products would emit phosphorus 0.0046 kg in a year. Besides, by comparing P emissions rate of the two livestock breeding subsystems, we can find that breeding unit livestock in small-scale way (average 0.0797 kgP/(cap.yr), didn‘t consider aquatic products) would emit almost 3 times phosphorus than breeding 206


in domestic way (average 0.0248 kg-P/(cap.yr)), that‘s probably because of the different diets between the two breeding ways, professional feed contains more phosphorus than kitchen wastes and grass. Upon closer analysis, the phosphorus emissions from beef cattle breeding are 10 times higher than the other livestock breeding in small-scale way, that‘s because of the high phosphorus content in beef cattle‘s living body.

Evaluation of Phosphorus Loads

Phosphorus loads are a useful parameter for the evaluation of anthropogenic influence on water quality and aquatic ecosystem balance. The calculation of P load was based on equations (6) and (7), which were used to calculate the process P loads per capita and per area respectively. Figure 6 shows the comparison of P loads per capita and by area in different districts.

L

p



Q , Population

L

a



Q , Area

where

L

p

(6)

(7)

represents phosphorus loads per capita,

L

a

represents phosphorus load by area,

Q

represents the total quantity of phosphorus discharged into surface water, Population represents the population in a given year, and Area is the aggregate area of the district.

Calculation inaccuracies and the use of data from different years limited the accuracy of this comparison. However, figure 4 clearly shows a general trend of extremely high P loads in Wuwei County, as evaluated by population (3.35 kg-P/cap/yr) and by area (19.43 kg-P/ha/yr).

25 Area-Specific Phosphorus Load(kg-P/ha.yr)

20 15

Population-Specific Phosphorus Load(kg-P/cap.yr)

10 5 0 Wuwei County in 2008

Lujiang County in 2008

Hefei City Chaohu in 2008 Lake Basin in 2007

China in 2002

Figure 4 Comparison of phosphorus loads in aquatic environments per capita and per area. Sources: Fan et al. 2008; EPDAP 2010; Li et al. 2010;Yuan et al. 2011.

P loads may be higher in Wuwei County for several reasons. Firstly, agriculture is the primary production activity in Wuwei County and about 88% of its residents are farmers who lack 207


sufficient education in agricultural technology and environmental protection and are more inclined to consume cheaper products with higher P content, also contributing to high P loads. Secondly, the scale of livestock breeding and farming is several times higher than average levels in the Chaohu Basin and Chaohu City. Finally, the lack of waste treatment plants in rural areas contributed to some extent to high P loads. Comparatively, Lujiang County‘s agriculture industry, as well as the economy, is not so prosperous as Wuwei County; Hefei City is dominated by industrial activities and has sufficient economic support and ready access to sufficient wastemanagement infrastructure. While the Chaohu Basin has the composite economic structure, which could maximize the phosphorus recycle and minimize the emissions, and the large area and population both could lessen the P loads as well.

Phosphorus Recycling

The last two columns of table 2 show the P emissions and recycling situation in the different processes. Discharged P was assumed directly emitted into the aquatic environment. Recycled P was calculated by subtracting discharged P from the total output of P waste, such as the P in manure reapplied to cropland and the P in kitchen waste recycled as livestock feed. Figure 5 presents a detailed analysis of P emissions by subsystem.

Figure 5 Proportions of discharged and recycled phosphorus (P) in the consumption process.

Figure 5 shows that the domestic livestock breeding subsystem had the highest P recycling rate, with 99% of manure (containing the overwhelming majority of P) recycled as agricultural fertilizer. The small-scale livestock breeding subsystem had the second-highest P recycling rate (67%), with 33.3% of manure recycled in croplands, 23.3% of manure reapplied to trees and plants in rural areas, and the remainder was stocked in the subsystem. The only effluent was inedible livestock waste, such as blood, hair, and bones, which accounted for a very small proportion of 208


total P.

The rural residential subsystem had the third-highest P recycling rate. Unlike the urban residential subsystem, the rural subsystem contained no waste treatment plants and sewage was thus discharged directly. Because the total population in rural areas was 10 times as large as that in urban area, the rural residential subsystem discharged a large quantity of P. However, rural residential excreta were usually disposed of together with the manure of domestic livestock, rather than being discharged.

The P recycling rate of the agricultural subsystem was the second-lowest. Straw was the main recycled material; an average of 91% of straw was recycled. However, this subsystem had a large quantity of P emissions, due to the widespread use of agricultural chemical products and the limited P absorption rate (10–30%) of crops (Malhi et al. 2002). This subsystem discharged 2,572 tonnes of P in 2008, accounting for 54% of the total P emissions in Wuwei County.

Analysis of Potential Measures Based on above analyses, the agricultural farming, rural residential consumption and small-scale livestock breeding activities caused the most phosphorus emissions. We think it‘s prime to find some feasible approaches to mitigate this three subsystems. So in this section, three options were created pointedly and the potential effects of these different measures were discussed by examining the advantages and disadvantages at the end of each option. 

Option 1: Popularization of precision fertilization. Because the excessive use of agricultural chemical products was the main reason for high P emissions in the agricultural subsystem, precision fertilization techniques should be promoted to reduce the use of P products and improve the P uptake rate. According to analysis on phosphorus emission of agricultural farming subsystem, the implementation of precision fertilization while all other factors remained unchanged would reduce the use of agricultural chemical products by 1,505 tonnes, thereby eliminating at least 470 tonnes of P emissions under ideal conditions. Advantages: 1. It could reduce 18% Agriculture Farming Subsystem‘s phosphorus emissions at the most; 2. It could reduce the chemical fertilizer cost; 3. It could benefit the cropland situation in the long run. Disadvantages: 1. It would have a high requirement for techniques; 2. The cost for hiring the technical personnel would be very high; 3. It would need related education for the rural residents.



Option 2: Construction of a sewage treatment plant versus village biogas pools. The construction of the Wucheng sewage plant, currently in the initial stage, is an important project in Wuwei County. Operation of the sewage treatment plant at full capacity (40 tonnes sewage/d; WBHUD 2008) would reduce P emissions in the urban residential subsystem by 44 tonnes. However, if: (1) the construction funds (1,300 million RMB; WBHUD 2008) were used for the construction of village biogas pools that effectively treat human and livestock 209


waste; (2) the construction cost of a 8-m3 pool was 1,700 RMB (AHNW 2004); and (3) each family had an average of five members, then 76,470 pools could be constructed that served 30% of rural families and reduced P emissions by 179.4 tonnes. Advantages: 1. It could reduce 1/3 Rural Residential Subsystem‘s phosphorus discharge; 2. It could improve the rural environment; 3. It could produce biogas for daily use. Disadvantages: 1. The construction projects would be numerous; 2. The construction cost would be paid by the rural residents. 

Option 3: Promotion of multiple recycling of P waste. The collection and reuse of all inedible livestock waste, such as blood, bones, and hair, in the livestock breeding subsystems would reduce P emissions. The reuse of this waste as a raw material, for example, in amino-acid livestock albumen feed or agricultural fertilizer would reduce farming costs and eliminate 291 tonnes of P discharge, equivalent to at least 2,425 tonnes of fertilizer (P content of phosphoric fertilizer ~12%; Marscher 1995). Advantages: 1. It could avoid the most phosphorus emissions from Small-scale Livestock Breeding Subsystem; 2. It could reuse the waste and make a profit from them. Disadvantages: 1. It would have a high requirement for techniques; 2. It would be hard to find an appropriate company just receives this kind of waste in a certain range.

Limitations Developing an inventory is a time and energy consuming work, so the P inventory developed in this article must have some emissions sources been omitted for different kinds of reasons. And in the case of Wuwei County, several P emission sources especially in government consumption and residential consumption, like refractory products, medicines, cloth, furniture, etc, were still missed due to the lack of reliable data.

Besides, because our calculations were made using several data sources and emission factors, our results incorporate a substantial degree of uncertainty. The data used in this study may be classified as belonging to the five uncertainty levels proposed by Hedbrant and Sörme (2001; Danius 2002). Due to the complex and less known of the accounting process, we demonstrated the uncertainty analysis result in table 3, which is simplified and comprehensible.

Basically, the data used in this paper were with relatively high confidence level. But there is still a portion of data with relatively high uncertainty, like field observations data, residents‘ questionnaire survey data and estimated data. The results derived from these subsystems might have comparatively large uncertainty. Nevertheless, these subsystems accounted for small proportion in the emissions of phosphorus, and the inaccuracy of data may not affect the final results dramatically. Take urban residential subsystem as example, which used relatively more data with large uncertainty, it just accounted for 2% of the emissions of phosphorus. Table 11 Uncertainty analysis of different data source 210


Basis of data

Data quality

Government documents and statistic data

High

Government website

High

Literatures

High

Experts interviews

High

Field observations

Medium

Residents questionnaire survey

Medium

Estimated

Medium

Comment of data Authorized and generally acknowledged Local situation related and generally acknowledged Professional related and high credibility Local situation related and high credibility Local situation related Local situation related but subjective Based on facts but subjective

Notes: High: interval level between /×1 and /×2; Medium: interval level between /×2 and /×4; Low: interval level above /×4. ( for example, the measured data is 1 and the interval level is /×2, thus the true value is between 0.5 and 2 )

Conclusion This study developed a relatively compete phosphorus emissions inventory within socioeconomic system which includes mining industry, manufacturing industry and farming, forest, livestock breeding and fishery industry. We then took Wuwei County as example, and calculated the total anthropogenic emissions of P in the year 2008. The results show that an extremely large P emissions in Wuwei County and a higher P load than in nearby cities and watersheds. The agricultural subsystem was the main source of P emission. The results also show that the developed inventory could help efficiently identify the sources of P pollutants and find the appropriate ways to mitigate P emissions.

Acknowledgement The research was financially supported by the Natural Science Foundation of China (41222012；40971302), the Fundamental Research Funds for the Central Universities, and the China Ministry of Science and Technology (MOST) National Research Initiative Grants Program for State Key Laboratories.

211


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213


Wiederholt, R. and B. Johnson (2005). "Phosphorus behavior in the environment." Environment Natural Resources NM-1298. Xi, D. (2003). "Thought of the safe crop produce in Wuwei County." Anhui Agricultural Science Bulletin 9(2): 26-27. (in Chinese.). Yuan, Z., X. Liu, et al. (2011). "Anthropogenic phosphorus flow analysis of Lujiang County, Anhui Province, central China." Ecological Modeling 222(8): 1534-1543. Zhang, Y. (2005). " Method of reducing poultry manure's nitrogen and phosphorus." Journal of Animal Science and Veterinary Medicine 24(1): 34-35. (in Chinese.).

214


LCA & Sustainable Cities

215


Tool for environmental analysis of domestic water use in buildings and urban environments Tito Morales-Pinzón* – Carles M. Gasol – Xavier Gabarrell – Joan Rieradevall * Facultad de Ciencias Ambientales, Universidad Tecnológica de Pereira (UTP), Colombia. La Julita, Pereira, Risaralda, Colombia. AA097

++57 6 3137227 [email protected] URL: http://www.utp.edu.co/ Other author affiliation Institute of Environmental Science and Technology (ICTA). UniversitatAutònoma de Barcelona (UAB). Campus de la UAB, Bellaterra (Cerdanyola del Vallès) 08193 Barcelona, Catalonia, Spain.

Abstract Trends in the development of urban areas are addressed in the quest for environmental sustainability. In order to achieve a true balance in managing for the sustainability of urban water resource, it is necessary to have technical analysis, economical, environmental and social tools that help to understand the dynamics water supply and demand in urbanized areas. Further analysis, especially of the demand for treated water which is still a rising trend as a result of the new urban development to meet the consequent water demand of the population.

The study has focused on the estimation of the environmental impact of urban domestic demand of water. To achieve this approach, the life cycle assessment (LCA) methodology has been used, which analyzes the environmental impacts of a product throughout its life cycle (from cradle to grave), or system that is required for a product to fulfill a specific function. We only considered the stages of classification and characterization (ISO 14040, 2000). The tool used is the Plugrisost software (developed by the authors), a dynamic model of water flow for domestic use, with emphasis on use of unconventional sources (rainwater and greywater); which incorporates as a method of calculation of impacts the Baseline 2001 v2.04 CML using the database ecoinvent 2.2, associated with the use of the program SimaPro7.2.0. The selected impact category used in this paper was global warming potential (GWP, kg CO2 eq.). New construction in the metropolitan area of Pereira (Colombia) was taken as case study. We studied two systems with different urban densities (semi-detached house and apartment building).

The most efficient was a building apartment system, where the results show that for a domestic water demand of 126 L/inhabitant/day, the different alternatives of water supply can be implemented. Mains water, rainwater and greywater used simultaneously can produce an potential environmental impacts of 0.99 kg CO2 eq./m3 of consumed tap water, 0.52 kg of CO2 eq./m3 for rainwater (to meet the demand for non-potable uses of laundry, 27%) and 0.33 kg CO 2 eq./m3 for the reuse of greywater (to meet the demand for non-potable uses of toilet, 20%). The integration of the three alternatives water sources in the system gives a favorable environmental potential impact. The use of unconventional water sources in urban systems can help to reduce the emissions of greenhouse gases in the cities. Key words: global warming potential, greywater, Life cycle assessment, rainwater, urban water. 216


Introduction The rapid growth experienced by some urban centers in developing countries determines planning authorities and water utility companies to look after alternatives that are economically viable, socially acceptable and produce less environmental impact. In Colombia the government has proposed a model of economic growth (and urban growth) with a planned increase bigger than 5% from 2010 onwards, and than 6% from 2014 onwards (Departamento Nacional de Planeación, 2005). This is affecting natural resources, including water, which is becoming a limited resource or at least one that is difficult to recover as a result of the pollution and degradation of the watershed from which urban water supply systems draw the water. The rate of urban growth in Colombia is 2.2%. The country has a predominantly urban population (71%) and an average density of 451 inhabitants per km2 urban areas, with 26 urban areas made up of 101 municipalities spread throughout the country (Instituto de Hidrología, Meteorología y Estudios Ambientales, 2001). These urban areas are causing most of the pollution of surface sources. Sewage is a major source of pollution in urban areas, since large cities in Colombia (Bogotá, Medellín, Cali) can only treat 32% of the waste water discharged into to water bodies (Superintendencia de Servicios Públicos Domiciliarios, 2006). The result of this is that Colombia does not appear among the top five of countries with the highest water availability anymore, and is now ranked 24th on a list of 203 countries (Instituto de Hidrología, Meteorología y Estudios Ambientales, 2008). Policies in countries with abundant water resources have focused more on reducing demand than on searching for non-conventional water resources. In Colombia, urban environmental management has focused on renewable natural resources as a first line of action. One of the main goals is the establishment of efficiency and water-saving programs for urban areas (Colombia. Ministerio de Ambiente, Vivienda y Desarrollo Territorial, 2008), focusing on four key strategies: setting targets for reducing losses, educational campaigns aimed at the community, strategies for the reuse of water, and incentives to promote the rational use of resources (Flórez et al., 2011). However the use of rainwater is an issue relegated to marginal or rural areas. The highest investment in water resource is intended for infrastructure development. For 2007, near of 88% of the investment in the management of water resources in Colombia (about 1100 million) were allocated for infrastructure development (Colombia. Ministerio de Ambiente, Vivienda y Desarrollo Territorial, 2010). Some studies have shown that in Colombia there is great potential for the use of non-conventional water resources such as rainwater. Morales et al. (2012a)showed the potential supply of rainwater in cities of Colombia finding that housing projects can meet the total water demand (56%) for different uses to human consummption. The use of rainwater could help to decrease the potential impact of domestic water consumption. Using data from Morales et al. (2011) the potential environmental impact of rainwater harvesting systems in a neighborhood of apartment buildings in Colombia is between 0.53 and 1.47 kg CO 2 eq./m3 of used rainwater. These values can be less than reported by tap water studies of life cycle assessment (LCA). Few studieshave been published onLCAofdrinkingwater production. Using data ofAngrill et al. (2011)and based on data reported by Muñoz et al. (2010), it is foundthat the potential impactona conventionaltap water(in Spain) is0.81 kg CO2 eq./m3 (0.37 for production and 0.44 for distribution). Morales et al. (2011) simulate GWP of 1.18 and 1.27 kg CO2 eq./m3 as potential environmental impacts in Colombian urban areas. 217


Objectives The aim of this paper is to present a tool for environmental assessment of unconventional water systems for urban domestic supported by the LCA methodology.

Methodology Study area and systems

The study was conducted in the municipality of Pereira (Colombia), with reference to the new construction reported in the national census of buildings. (Departamento Administrativo Nacional de Estadísticas, 2012). From thesedataandusingthecatchmentarea estimatespresented byMorales.et al. (2012a),two rainwater harvesting (RWH) systems have been studied, Single-house and Apartment building, respectively (see Table 1).The studiedsystems correspond tourban projectsasthepredominanttype of housingin the city ofPereira. Table 12.Design values of the non conventional water systems studied.

Variable

Apartment building

Single house

Domestic water demand (L/day) Domestic rainwater demand (laundry water use) (L/day) Domestic greywater demand (toilet water use) (L/day) Catchment area (m2) Homes Inhabitants Runoff coefficient (0-1) First-flush volume (mm) Filter Coefficients (0-1)

20133 5436 4027 500 40 160 0.9 1 0.9

503 136 101 40 1 4 0.9 1 0.9

System boundaries

Using Plugrisost software (Morales-Pinzón et al., 2012b) the uptake, storage and distribution of rainwater and the reuse of grey water in each system were studied. The life span of the system was 50 years, which is in accordance with the proposal by Roebuck et al. (2011).The quantities of materials and energy used by the system were estimated using the software Plugrisost. A concrete tank with a polypropylene pipe and a stainless steel bomb was simulated. The rainfall in the area was obtained from historical records of the years 2008-2011 reported by the Red Hidroclimatológica del Departamento de Risaralda (Universidad Tecnológica de Pereira, 2012).

Functional unitand environmental impact

Plugrisost software simulate the potential environmental impacts for the life cycle analysis of RWH systems. This is based on four main steps: definition of the objectives and scope of the study, inventory analysis, impact assessment, and interpretation (ISO 14040, 2006). The functional unit was defined as the collection, storage and supply of 1 m3 of non conventional water (rainwater or greywater) to be used as non-potable water for laundry (rainwater) or toilet (greywater) with a constant demand over a span of 50 years (see Table 1).The CML Baseline was used as life cycle impact assessment method, Guinée et al. (2001), and Global Warming Potential (GWP, kg CO2 eq.) was the selected impact category. The general model applied the system dynamics methodology developed by Forrester (1961). This methodology defines a system from two basic structures, Level and Flow, usinga four-tiered structural hierarchy (Richardson, 2011). 218


Mathematical equations support the technical component of the Plugrisost software including a detailed inventory of the materials and processes required for construction(collection, storage or distribution) (Morales-Pinzón et al., 2012b). For each material, the potential environmental impact per unit of measurement is calculated, using the ecoinvent database (Swiss Centre for Life Cycle Inventories, 2009) and the SimaPro software (PRé Consultants, 2010). TheSimaPro results are used by Plugrisost and the quantities of material are estimated using lineal models according to the storage capacity and rainwater or greywater system. Plugrisost simulate the potential environmental impact of the water systems.

Results and discussion Storage capacity according to potential environmental impacts

According to the simulation, to obtain an optimal storage capacity in greywater system, is required to find the storage tank to meet up to 100% of the demand with the minimum infrastructure required. For the Single-house system the minimum storage capacity simulated (0.5m3) is able to meet the 100% ofgreywater demand. For the Apartment building an adequate volume of 8m 3is able to meet 100% of rainwater demand. Simulating the potential environmental impacts, we found optimum greywater storage capacitiesof0.5 m3 and 8 m3 for Single-house and Apartment building, respectively (see Figure 1).For Single-house system, GWP is between 0.67 and 1.43 kg CO2 eq./m3 and for Apartment building, GWP is between 0.33 and 0.39 kg CO2 eq./m3(see Figure 1).

Figure 10.Potential environmental impact of greywater system in Single-house and Apartment building.

Figure 11. Percentage of water demand met in Single-house and Apartment building systems The averages of the demands met were 43 and 99% for rainwater and greywater demands, respectively. Respect to all domestic water demand, the percentages of water demand met were 22.6 (rainwater) and 19.7 (greywater), in Single-house system; and they were 11.7 (rainwater) and 219


19.8 (greywater), in Apartment building system (see Figure 2).

Potential environmental impacts for the three systems (rainwater, greywater and tap water) Using the optimum greywater storage capacities, we found that GWPis lowerwhencombiningthe threealternatives ofdomestic watersupply.GWP for greywater system are 0.68 and 0.33 kg CO2 eq./m3 for Single-house and Apartment building, respectively (see Figure 3). In this scenario, potential environmental impact (GWP) for rainwater system for Single-house system is between 0.53 to 0.83 kg CO2 eq./m3(see Figure 3), while GWP for Apartment building is between 0.42 to 0.62 kg CO2 eq./m3(see Figure 3). Integrating rainwater, greywater and tap water systems, average of GWP are 1.02 and 0.99 kg CO2 eq./m3 for Single-house and Apartment building respectively (see Figure 3). Potential environmental impact is less than reported by Morales et al. (2011) in similar systems (see Figure 3).The avoided GWP due to implementing nonconventional water supply is 0.27 kg CO 2 eq./m3. This value is similar to data reported by Morales et al.(2011) for rainwater harvesting systems in Colombia (these systems canreduce the GWP by 0.22 and 0.25 kg CO2 eq.).

Figure 12. Potential environmental impact (GWP) of domestic water use in Single-house and Apartment building systems

Conclusions Plugrisost software facilitated the simulation of different scenarios required in the study. This tool helps to integrate the unconventional water supply (rainwater and greywater) and tap water. When using unconventional water sources to replace domestic demand for water that does not require drinking water quality, it was found a lower environmental impact potential than using mains water. In Apartment building system, the unconventional water source with less environmental impact was greywater, while in Single-house the least environmental impact was the rainwater. The lowest GWP (0.33 kg CO2 eq./m3) of greywater system was found in Apartment building and similarly, the lowest GWP (0.42 kg CO2 eq./m3) of rainwater system was found in the same system. The environmental impact potential of the domestic water use system is reduced when two or three alternatives are combined. The best result is obtained when combining the two unconventional sources (rainwater and greywater) with tap water. When all systems (rainwater, greywater and tap water) are integrated, GWP is less than for tap water. Selecting the suitable water source as a function of different uses in domestic water demand is an alternative that should be promoted in the development of new neighborhoods, being better in 220


Apartment building systems.

Acknowledgment Theauthorswishtothanktheprojects ―Metabolismo urbano y análisis ambiental del aprovechamiento de agua no convencional en edificaciones más sostenibles‖ (Vicerrectoria de Investigaciones, Innovación y Extensión, Universidad Tecnológica de Pereira, Colombia). Also, theauthorswouldliketothanksforthe "ECOTECH SUDOE SOE2/P1/E377, LCA and Ecodesign International networkforenvironmentalinnovation" project; and theSpanishMinistryforScience and Innovationthroughtheproject ‗Análisis ambiental del aprovechamiento de las aguas pluviales‘ (PLUVISOST CTM2010-17365).

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ISO 14040. (2006). Environmentalmanagement —lifecycleassessment— principles and framework. International Standard 14040. International OrganisationforStandardisation, Geneva. Morales-Pinzón, T., Angrill, S., Rieradevall, J., Gabarrell, X., M. Gasol, C., & Josa, A. (2011). LCM of RainwaterHarvestingSystems in EmergingNeighborhoods in Colombia. In M. Finkbeiner, & M. Finkbeiner (Ed.), TowardsLifeCycleSustainability Management (pp. 277-288). Berlin: Springer. Morales-Pinzón, T., Rieradevall, J., M. Gasol, C., &Gabarrell, X. (2012a). Potential of rainwaterresourcesbasedonurban and social aspects in Colombia. Water and EnvironmentJournal , 26 (doi:10.1111/j.1747-6593.2012.00316.x), 550-559. Morales-Pinzón, T; Rieradevall, J; M. Gasol, C &Gabarrell, X. (2012b).Plugrisost v1.0. Modelo dinámica de flujos de agua para uso doméstico, con énfasis en aprovechamiento de fuentes no convencionales (pluviales, grises). Grupo de Investigación en Sostenibilidad y Prevención Ambiental (Sostenipra), Universidad Autónoma de Barcelona (España) y Grupo de Investigación Gestión Ambiental Territorial (GAT), Universidad Tecnológica de Pereira (Colombia).Available (Spanishversion) in http://plugrisost.sostenipra.cat. Muñoz, I., Milà-i-Canals, L., & Fernández-Alba, A. (2010). LifeCycleAssessment of WaterSupplyPlans in MediterraneanSpain. The Ebro River Transfer Versus the AGUA Programme. Journal of Industrial Ecology , 14 (6), 902-918. PRéConsultants. (2010). SimaPro 7.2.0. Amersfoort, TheNetherlands. Richardson, G. (2011). Reflectionsonthefoundations of systemdynamics. System Dynamics Review , 27 (3), 219–243. Roebuck, R., Oltean-Dumbrava, C., &Tait, S. (2011). Wholelifecost performance of domestic RWH systems in theUnitedKingdom. Water and EnviromentJournal , 25, 355-365. Superintendencia de Servicios Públicos Domiciliarios. (2006). Estudio sectorial de acueducto y alcantarillado 2002-2005. Available in http://www.superservicios.gov.co/c/document_library/get_file?folderId=65121&name=DLFE4235.pdf. Universidad Tecnológica de Pereira. (2012). Red Hidroclimatológica del Departamento de Risaralda. AccessedAugust 2012 from http://www.utp.edu.co/hidroclimatologica/es/inicio.

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The State of the Art of LCA in the PCCI context in Brazil Katia Broeto Miller Raquel Naves Blumenschein Armando de Azevedo Caldeira Pires Maria Vitória Ferrari Duarte Tomé (1) FacultyofArchitectureandUrbanism, Gleba A, ICC Norte, Campus Darci Ribeiro, Universityof Brasília, Asa Norte, CEP: 70910-000, Brasília-DF, Brazil.

55 (61) 3107 7482, [email protected], www.unb.br (2) FacultyofArchitectureandUrbanism, Gleba A, ICC Norte, Campus Darci Ribeiro, Universityof Brasília, Asa Norte, CEP: 70910-000, Brasília-DF, Brazil.

55 (61) 3107 7482, [email protected], www.unb.br (3) Faculty of Technology, Department of Mechanical Engineering, Campus Darcy Ribeiro, University of Brasília, Asa Norte, CEP: 70910-000, Brasília-DF, Brazil.

55 (61) 3107 5503, [email protected], www.unb.br (4) Faculty UnB Gama, Área Especial 2, Lote 14, Setor Central, Gama-DF, Cep: 72405-610, Brasília-DF, Brazil.

55 (61) 3107 8219, [email protected], www.unb.br

Abstract PurposeThe Life Cycle Assessment (LCA) is an essential tool to visualize the flows of materials and energy and the potential environmental impacts associated with construction materials and products. Understanding the degree of evolution of LCA dissemination is important to define guidelines on researches and national programs. Our goal in this paper is to create a panorama of LCA applied to the Productive Chain of the Construction Industry (PCCI) in Brazil. Methods This research was conducted in two stages: first a characterization of LCA applied to Construction Sector in the public and productive sectors and in the academy, gathering data on: LCA in the public sector; LCA in the thirty biggest building companies in Brazil, in sustainability reports of companies, in selected vendors, and in institutions that represent the productive sector; and the technical and scientific production related to LCA and Construction in databases of doctoral and master degree thesis and scientific articles. Second, we analyze the information gathered, quantifying and crossing the data obtained. Results In these surveys, LCA initiatives were identified in the three sectors. The public sector approved the Brazilian Program of LCA that seeks to develop models of LCA application and promote the development of Life Cycle Inventories (LCI). In the productive sector, the most of 223


LCA initiatives apply the LCA concepts, but do not develop LCA. We identified 26 LCA initiatives with constructors and vendors of PCCI. In the academy, we identified 28 technical and scientific production related to LCA and Construction:21 master degree thesis, threedoctoral degree thesis, and four papers. Brazil is in an early phase of LCA application, where the most of technical and scientific productions discuss construction materials and components and the initiatives in productive sector are on inventories of the natural resources and CO2 emissions. This kind of study is a previous and essential step to develop studies about the final products in PCCI, since it will provide data to build LCI. Conclusions In this context, the LCA is little widespread because of the complexity, capillarity and characteristics of PCCI and its finals products, which involve a large number of agents, materials, and services, high costs, and the lack of national database. Nevertheless, the PCCI visualizes in LCA an important toolfor Construction sector, in which there are many negative environmental impacts and the demand of built environment is fundamental and growing.

Keywords Productive Chain of the Construction Industry, Life Cycle Assessment,State of the Art, Public sector, Productive sector, Academy.

2. Introduction One of the challenges for the 21st century, as defined by the United Nations, is to guarantee the sustainability of life on planet Earth, integrating the principia of sustainable development to national policies and programs and reverting the depletion of natural resources and the GHG emissions (ONU, 2012). Initiatives that promote sustainability are essential to meet this goal, especially in the Construction Industry. This sector uses 40% of the natural resources and energy produced in the world, 17% of the potable water available and generates 40% of the waste (Athenas, 2000). Considering the environmental impacts created by the Productive Chain of the Construction Industry (PCCI), we observe the need to understand the lifecycle of the construction materials and to see more clearly the details and ecological mathematics involved in this process (Goleman, 2009). The Industrial Ecology is the science which seeks to master this ecological mathematics and consists of studying material and energy flows in industrial and consumer activities, the consequences of these flows to the environment and the economic, political, regulatory and social influences in these flows, uses and transformations of the resources (Goleman, 2009; Ayres, 2010). This science deals with the industrial system as ecosystems, because it considers the productive chains so integrated with each other that the waste of a process might be the raw material for another, forming an interdependent cycle like that of living systems. Among the tools used by Industrial Ecology we highlight the Life Cycle Assessment (LCA), in which a product, material or process has all the stages of its lifecycle analyzed, from extraction of raw materials to the final disposal or re-use of the materials, passing through the manufacturing process, transformations, storage, shipping and consumer usage (Vigon et al, 1995). LCA is a method which allows the systematic break down of a manufactured good into its parts, components and industrial processes, as well as measuring the potential negative environmental impacts and quantifying the energy and material input. LCA is the monitoring of data, inputs and outputs of the process, and shows in detail the stages which might be optimized both environmentally and economically (Vigon et al, 224


1995). This method was first developed when the Coca Cola Company hired William Frankling in 1969 (Keeler et al, 2010). The company commissioned a study to investigate the implications of using plastic instead of glass for the bottles. This study is considered a pioneering effort in the analysis of the cost of the lifecycle costs which would originate LCA. It was only in 1990 that the Society for Environmental Toxicology and Chemistry (SETAC) held a global event which resulted in a common structure and language for LCA. Later the institutionalization of LCA originated the ISO 14.040 standard, which defines parameters for application of the analysis method and presentation of obtained results. The application of the LCA methodology to the PCCI makes it possible to plan sustainable buildings. One of the hurdles preventing the adoption of sustainable practices in construction is the difficulty to understand and quantify both environmental and economic costs associated with less polluting materials and buildings. LCA makes this quantifying and the publishing of benefits from sustainable practices in construction (Keeler et al, 2010). Notwithstanding the green labels and certificates for buildings, Goleman (2009) claims that few products labeled ‗green‘ have gone through a systematic evaluation of the true benefits provided by the products, and highlights the importance of the LCA method to gather these kind of data and information. Seeing the importance of applying LCA methods to the PCCI and the environmental impacts associated with this productive chain, the goal of this article is to draw a panorama of the LCA application in the PCCI context in Brazil, regarding public and private sectors and the academy.

3. Methodology The methodology we use in this research has two stages: (a) Stage 1: identification of LCA applications in the Construction Industry in Brazil; and (b) Stage 2: analysis of the data collected. The first stage focuses in identifying LCA applications in the public and private sectors and the academy. For the public sector, we survey public initiatives in the LCA field in the main institutions and ministries of the Federal Government. For the private sector, we identify initiatives for application of LCA in the 30 largest construction companies in Brazil, ranked by area built as listed by the Brazilian Enterprise Council for Sustainable Development (CEBDS in Portuguese) as published in 2004, 2008/2010, in the best vendors in the construction industry according to the 2010 ranking by PiniEditora (a publishing house), and other private institutions. To carry out the survey with the best suppliers, we considered the three best suppliers in each of the 36 categories (PINI WEB, 2012). This amounted to 89 suppliers. We conducted a search in the companies‘ websites with the keywords ―ACV‖ (LCA in Portuguese), ―Avaliação do Ciclo de vida‖ (Life Cycle Assessment in Portuguese), ―LCA‖ and ―Life Cycle Assessment‖, just like this, in English. We also conducted this search in the websites of the biggest builders by built area. We also searched technical and scientific publications from Brazil related to LCA and the PCCI in the following databases: Digital Library of Thesis and Dissertations from the Brazilian Institute for Science and Technology Information (IBCIT, in Portuguese); the Thesis and Dissertations Library of the Coordination for Improvement of Personnel (CAPES, in Portuguese); publications from PhDs registered in the Lattes database of academic curricula from theNational Council for Scientific and Technological Development(CNPq, in Portuguese) as well as thesis and dissertations written and oriented by them; Peer reviewed publications for Architecture and Urbanism and for Civil Engineering with grades A1, A2, B1 and B2 as assigned by the CAPES Qualis website, and In the Life Cycle Assessment Community Library. 225


In the second stage, we analyzed, quantified and summarized the data we collected in the surveys to build a panorama of the LCA applications to the PCCI in Brazil.

4. Results Initiatives applying LCA methods in the context of the Construction Industry identified in the three sectors (public, private and academy) were used as reference for drawing a panorama of the state of the art of LCA in Brazil. 4.1. LCA in the Public Sector In the scope of the public sector, the Brazilian Program for Lifecycle Analysis (PBACV in Portuguese) was identified as a LCA initiative in the construction industry. This program integrates agents of different economy sectors, including the Construction, who work in groups, considering the development of this program as part of the National Plan of Sustainable Production and Consumption directly linked with the National Policy for Environmental Changes and the National Policy for Solid Waste, Brazilian law 12.305/2010 (Brasil, 2010). The LCA insertion in the Public Sector started in 2006 with the project Life Cycle Inventory for the Brazilian Industry Environmental Competitiveness (SICV Brasil) under the coordination of the Brazilian Institute for Science and Technology Information (IBCIT, in Portuguese) and of the National Institute of Metrology and Quality (Inmetro, in Portuguese) (Cavalcanti, 2009). The SICV Brasil project goal is to build a database to store the Lifecycle Inventory (ICV in Portuguese); to establish a standard LCA methodology which meets the ABNT NBR ISO 14.040 and 14.044; to compile and disseminate information on LCA and LCI, and to train people to carry out Lifecycle inventories and assessments. This project lasted three years, from 2006 to 2009. In 2010, the National Council for Metrology, Standardization and Industrial Quality (Conmetro in Portuguese) approved the creation of the PBACV that built on the efforts of SICV Brasil, supporting the sustainable development of the Brazilian output and the environmental competitiveness of the Brazilian industry, promoting access to domestic and foreign markets. (Conmetro,2010). The PBACV has the goals of implementing an internationally recognized system that organizes, stores and disseminates information on the Lifecycle Inventories of the Brazilian industry; creating baseline inventories; supporting the development of an informed public opinion; disseminating information on the lifecycle approach; intervening andinfluencing the development of national and international standards; and identifying the categories of environmental impact most relevant to the Brazilian context (Conmetro, 2010). Besides these, the program also seeks to raise awareness in the government and private institutions about the application of LCA, considering the environmental competitiveness of the Brazilian industry (Cavalcanti, 2009). According to Conmetro (2010) Brazil has a program for developing a Life Cycle Inventory aligned with the international Life Cycle platform. Nevertheless, the involvement of the private sector is limited and there is much room for improvement in the application of LCA in Brazil. Conmetro (2010) claims that the program should align strategically with the national environmental policies, such as the National Plan for Sustainable Consumption and the National Policy for Solid Waste. The latter already presents LCA elements such as reverse logistics of hazardous materials and the sharing of responsibilities along the lifecycle of the products, among the agents involved in the process. Currently the PBACV holds regular meetings with the Coordinators of the Technical Commissions to 226


define action plans for each category and for the Coordinating Committee. The Construction Industry is represented by a Work Group with the participation of the University of Brasília (UnB, in Portuguese) and the Brazilian Construction Industry Chamber (CBIC, in Portuguese) (Caldeira-Pires, 2012). Another government project identified is the publishing of the Blue Label Guide, by ―CaixaEconômica Federal‖, a major public bank. The guide deals with the lifecycle of buildings and recognizes the value of a wide view of the built environment, taking into account not only the construction phase, but also the occupancy and the end of life of the building (John et al, 2010). Nevertheless, LCA has not been included in the selection criteria, since there is no LCA certification available in Brazil. According to John et al (2010) the implementation of LCA in Brazil will bring greater objectivity to the decision making process of the construction industry regarding the negative environmental impacts of the construction materials and components. But the application of LCA depends on the development of a national database, definition of parameters and the inclusion of criteria to evaluate the informality in the industry as a factor in the sustainability of the final product. 4.2. LCA in the Private Sector In the survey we conducted with the 30 largest construction companies in Brazil, as ranked by ICTnet, in 2011 five results indicate indirect application of LCA (ICTnet, 2012). The sustainability reports from the Brazilian Enterprise Council for Sustainable Development (CEBDS, in Portuguese) from 2004 and 2008/2010 present four results (CEBDS, 2004). And the survey we conducted with the best suppliers in the construction industry, according to the ranking created by Editora PINI, sixteen results referring to applying LCA to these suppliers‘ materials were obtained. The results from this survey are summarized on Table 1. We highlight that in the described cases, little detail on the inventories is published by the companies, with information lacking on how the results were obtained and the methodology adopted.

Table2Summary of the results from the survey on the private sector

Results from the best Constructors in Brazil (ICTnet) Company

LCA Application

Construtora

Concluded, in 2007, the Eldorado Business Tower development, with LEED Platinum certification, which includes LCA concepts in its evaluation.

Gafisa Const. e Incorporadora Even Rossi Residencial

Carried out a GHG inventory and reached the figure of 0.271teq CO 2/m2of built area. Carried out an energy and water consumption and waste generation inventory, to define targets for improvement.

Trisul

Mapped and monitored the CO2 emissions related to its buildings construction, in 2010 and 2011.

Grupo Camargo

Carried out an inventory of direct and indirect optional GHG emissions in 2010. The 32 developments analyzed in 2009, and the 30 analyzed in 2010 have emitted, respectively, 899 thousand and 740 thousand teqCO 2.

Correa

Results from the CEBDS Sustainability Reports2004 and 2009/2010 Company

LCA Application

227


Grupo Amanco

Has identified 16 critical points along the PVC tubes lifecycle, such as: elimination of heavy metal based paint, elimination of naphthalene based plasticizers and substitution of lead based stabilizers with calcium and zinc based ones.

Gerdau

Received the Falcão Bauer Ecologic Label recognizing that the rebars, steel screens, and steel meshes, as environmentally sustainable materials, analyzing the adequate use of resources and the generation of waste.

Alcoa

Carried out an inventory of GHG emissions in 2009, which amounted to 2.13 million teqCO2, 17% less than 2008.

Grupo

Carried out corporate inventories of carbon emissions and stimulates the clean

Votorantim

development mechanisms which reduce emissions, energy consumption and allows for trading carbon credits.

Results from the best suppliers in the Construction Industry (PINI Editora) Company

LCA Application

Soletrol

Carried out the LCA for a Compact Solar Heater, comparing it to two other heating systems. Carried out an inventory of CO2 and other gases‘ emissions and energy and water consumption and waste each year on the plant. Conducted LCA at the Japan division, but there is no forecast for applying the method in Brazil

Bosch YKK Esquadrimeta l

Carried out an inventory of CO2 emissions, totaling 60 teqCO2 in 2007, considering:

Polimix

Carried out an inventory of GHG emissions in the headquarters, Brazilian plants and its equipment in 2010. Mentions investments in LCA but offers no further details. Developed a tool for comparing products: the Product Eco-Performance Improvement Table, which evaluates the energy and raw material consumption and allows for environmental impact reduction for new products. The USA division applies LCA to the products generating EPDs. The categories considered in the analyses were: primary energy, global warming potential, eutrophication, acidification, and smog generation potential. Recognizes the importance of LCA for their products, but has not applied the tool yet. Applied LCA to its products and has already identified potentially impacting substances. Collaborated with a study on materials based on their lifecycle. Has substituted lead based stabilizers for calcium and zinc based, due to LCA studies. Applied LCA to the auto parts of a new category made by the company (S-in motion). The Falcão Bauer Institute has analyzed and certified the steel produced by the company according to energy and water consumption and solid and liquid waste generated, emissions and raw material used.

Siemens Atlas Schindler ThyssenKrup p Viapol Bticino Docol Tigre e Amanco Arcelor Mittal Votoraço

commute, energy consumption, waste generation and shipment of aluminum.

In institutions representatives of the productive sector, initiatives were identified in the Brazilian Construction Industry Chamber (CBIC in Portuguese) and the Brazilian Committee for Sustainable Construction (CBCS in Portuguese). CBIC launched in 2011 the Sustainable Building Program containing goals which aim to contribute to the improvement and effective implementation of PBACV, by supporting the actions developed by the 228


program. CBIC emphasizes the need to incorporate simplified LCA methodologies to the PCCI, able to be quickly absorbed by the industry and that the results are consistent with models (BIM Building Information Modeling) (CBIC, 2011). For CBCS, LCA is a tool that enables the quantification of the environmental impact of a product, a system or a process, i.e. environmental accounting. "Cradle to grave" analysis allows you to compare the environmental impact of different products with similar applications. However, it highlights the problem of data load (Hachich et al, 2009). According to Hachich et al (2009) on behalf of the Brazilian Council for Sustainable Building (CBCS in Portuguese), construction materials and products have been selected by ignoring the differences between companies, such as informality and eco-efficiency, and the stage of use of the material, such as durability. And emphasizes the importance of LCA applied to the context of construction. For the CBCS, the application of LCA methodology, products‘ environmental claims and improvement of the industry value chain are actions for the future of CPIC in Brazil. Moreover, CBCS is developing a simplified LCA that reduces inventory for CO2 emissions, energy consumption and water consumption, waste generation, resource use and toxicity of the material (CBCS, 2012). 4.3. LCA in theAcademy In Brazilian databases of theses, dissertations and articles researched, 28 publications on the theme of LCA and Construction were identified, of which 21 were dissertations, three theses and four articles, considering the period from 2001 to 2010. As for the stratification of the theme of theseworks, unlike the world trend, research in Brazil is dominated by construction materials and components: 72% productions are related to materials and components; 21% to buildings and 7% to LCA concepts and software. The academic productions were plotted on a map according to source, classified by theme and type of publication (thesis, dissertation or article) (Figure 1). According to the academic research investigated, the materials studied in Brazil are: ceramic coating, exterior paint, bamboo, steel pillars compared to concrete, ceramic insulation, bricks, plastic vs. natural wood, pine wood, Portland cement, paints, ceramic vs. concrete blocks, red ceramic, flooring and fiberglass. In the sample universe researched most academic production is concentrated in the South and Southeast of the country, mainly at the University of São Paulo and Federal Universityof Rio Grande do Sul, where the academic production covers both building materials‘ and buildings‘ LCA. With the exception of these two regions, there are only two publications at Universityof Brasília with a focus on construction and concepts involving LCA and a publication at the Federal University ofAlagoas focused on the study of bamboo as an alternative building material.

229


Figure 1 Spatialization of Brazilian academic production in LCA and Construction

The technical and scientific publications on LCA and PCCI in Brazil are regularly published since 2000, when they started appearing. There is a slight reduction in 2006 and 2008 and then it increases again after 2009. Notwithstanding a rapid growth in LCA publications in the world in the last three years, Brazilian publications are still not expressive, with peaks in 2002, 2004 and 2009. For a better visualization of the relevant information in these publications, a summary table was created (Table 2) with the title of the publication and its main results. Table 2 Summary table of the academic publications in Brazil

Title/year

Main results and considerations

Environmental analysis of the feasibility of product

The use of software provides convenience and

selection through construction and LCA software

reliability, but performing procedures without a

Bees 3.0/2007

Brazilian database can distort the data.

Multidimensional analysis of sustainability of

The use of this material may have less impact than

lifecycle of a system of structural coverage of pine

other materials, since wood is a renewable material

wood: case rural settlement Pirituba II/2008

which captures CO2 from the atmosphere.

Environmental analysis of the production process

There are problems in the application foreign

of ceramic tiles: Applying LCA/2004

database for quantifying the LCA in Brazil.

Comparison processes for producing ceramic

The concrete is more compatible with the

bricks and concrete for structural masonry by

environment.

LCA/2002 Inventory of the Production of ceramic tiles and

LCA inventory for ceramic floors and bricks

bricks in the context of LCA/2004 Estimating the embodied energy of red ceramic

Environmental impacts from the productive processes

materials in Rio Grande do Sul/2005

of the red ceramic industry with qualitative and quantitative aspects regarding energy consumption.

230


Evaluation of Buildings in Brazil: the

Highlights the impossibility of simply importing

environmental assessment for the assessment of

research methods from developed countries with

sustainability/2003

different conditions.

Evaluation of the use of bamboo as an alternative

The material is feasible for social housing in Brazil

material for the implementation of affordable

and the problems identified were related to the

housing/2008

project.

Environmental LCA applied toConstruction:

The addition of cement to construction waste is

Comparison of Portland cement with added

beneficial for resistance of the product and for the

waste/2002

disposal of waste.

Characterization of environmental impacts of

The companies surveyed have initiatives with low

industrial ceramic red RS/2001

environmental impact, but we need to reduce loss and improve working conditions.

Environmental impacts caused by Red Ceramic

The impacts of use of natural resources, energy

Industry of Rio Grande do Sul/2003

sources, generation of solid waste and emissions were identified.

LCA of ceramic products from the construction

Identified problems in the use of foreign LCA

industry/2003

databases in Brazil.

LCA of a structural element: steel x concrete

The concrete pillar has fewer environmental impacts

pillar/2010

than the steel pillar.

5. Conclusion From the analysis of the obtained results, we observe that LCA is a methodology with little penetration in Brazil, mainly because of its high costs, the lack of a Brazilian database and the time commitment needed by the research. Besides, the PCCI is very complex and fine grained, and involve a large number of agents, materials and services, which makes the application of LCA a hard, time consuming and high cost activity. There are many construction materials which lack research on their lifecycles, and the application of LCA in Brazilian buildings is still not widespread in the market and the costumer has little access to this information. Compared with the rest of the world, the application of LCA in Brazil is still in an early stage, and most publications deal with LCA of materials and components and not the whole building. Conducting LCA of materials is a preliminary and essential stage for the application of LCA to buildings, since it will provide the data for the evaluation of housing and buildings and to form a Life Cycle Inventory. The early stage of LCA in the construction industry in Brazil is also evident in the initiatives found in the private sector. Most of the surveyed projects concentrated on GHG inventories or simply CO 2, and energy and water consumption and waste generated, which demonstrates a selective cut out of the data, focusing only on the inventories and not in the analysis of potential environmental impacts that the studied materials may cause. The main challenge defined in Agenda 21 for the sustainability of the Construction Industry is the search for sustainable development in the PCCI, claimed to be the main contributor to the socioeconomic development of each country (CIB; UNEP, 1999). After the publication of this document, a movement seeking to create policies for the sustainable development of the PCCI started. Considering LCA applied to construction materials, there are projects funded by the Habitare government program, a partnership between CaixaEconômica Federal and Finep established in 1994. Nevertheless, with the end of the program and of funding, many projects changed focus or closed altogether. 231


Another point which could be highlighted from the survey carried out for this article is that few theses are identified with the themes of LCA and construction materials, which demonstrates the latent demand for more detailed studies. Some research used softwares available on the market to obtain data, but some studies highlight the lack of precision in the final results obtained with those softwares. These programs use databases created in their countries of origin, which can distort results if used in other scenarios or contexts. There is still the immediate need for the creation of a Brazilian database for the development of LCA with support from software developed in other countries, economically, socially and technologically different from Brazil. Besides, it is important to identify the drivers of change in the PCCI so that the LCA technology can be absorbed by the PCCI and may be used to improve the environmental performance of materials and final products. Notwithstanding the existence of initiatives for LCA development in Brazil, there is still much to be studied and structured in this area, mainly in the construction industry, in which the level of pollution is high, across the whole supply chain, and the demand for the built environment is growing and fundamental for the development of the country.

Acknowledgments ThisprojectwasfinanciallysupportedbyCâmara Brasileira da Indústria da Construção (CBIC), CNPq-Braziland Universidade de Brasília.

References Athena (2000) Building as Products: Issues and Challenges for LCA. International Conference on Life Cycle Assessment: Tools for Sustainability. Arlington, Virginia. Ayres RU, Ayres L W (2002) A Handbook of Industrial Ecology. Cheltenham: Edward Elgar Publishing Limited. BRASIL(2010) Lei n. 12.305. Institui a Política Nacional de Resíduos Sólidos; altera a Lei n. 9.605, de 12 de fevereiro de 1998; e dá outras providências. Caldeira-Pires A (2012) Grupos de Trabalho: Planejamento Estratégico. [mensagem pessoal]. Mensagem recebida por . 16 January2012. Cavalcanti E (2009) Programa Brasileiro de Avaliação do Ciclo de Vida. Workshop Mercosul. http://www.mdic. gov.br/arquivos/dwnl_1283451608.pdf. Accessed 20 February 2012. CBCS (2012)Plataforma Global de Avaliação do Ciclo de Vida Simplificada para a Construção Sustentável. http://www.cbcs.org.br/userfiles/download/CBCS_Rio+20_PlataformaGlobaldeACVsparaConstrucaoSuste ntavel.pdf?.Accessed 22 March 2012. CBIC (2011) Desenvolvimento com Sustentabilidade: Construção Sustentável. http://www.cbic.org.br/sites/default/files/Programa-Construcao-Sustentavel.pdf.Accessed 10 January 2012. CEBDS. Relatório de Sustentabilidade Empresarial. 2004. Brasília. ______. Relatório de Sustentabilidade Empresarial. 2010. Brasília. CIB; UNEP (1999)Agenda 21 for Sustainable Construction in Developing Countries: A discussion document. Pretoria: Capture Press. Conmetro (2010) Resolução nº 4, de 15 de dezembro de 2010. Dispões sobre a aprovação do Programa Brasileiro de Avaliação do Ciclo de Vida e dá outras providências. Diário Oficial da União, ano CXLVIII, nº 2, Seção 1, Brasília. 232


Goleman D (2009)Inteligência Ecológica: O impacto do que consumimos e as mudanças que podem melhorar o planeta. Tradução de Ana Beatriz Rodrigues. Rio de Janeiro: Elsevier. Hachich VF (2009) Desafios de Seleção de materiais e fornecedores. http://www.cbcs.org.br/ sushi/images/see_pdf/Vera%20Hachihe%20Sem.%20CBCS-CDHU%2005-11-09.pdf. Accessed 30 April 2012. ITCnet (2012) Classificação: 7º Ranking ITCnet 2010 – As maiores construtoras da construção.http://www.portalvgv.com.br/site/wpcontent/uploads/2011/03/classificacao_100_maiores_ranking.jpg>. Accessed 28 February2012. John VM, Prado RTA (2010) Selo Casa Azul: Boas práticas para habitação mais sustentável. São Paulo: Páginas & Letras. Keeler M, Burke B (2010) Fundamentos de projetos de Edificações Sustentáveis. Porto Alegre: Bookman. ONU (2012) A ONU e o desenvolvimento. http://unic.un.org/imucms/rio-de-janeiro/64/38/a-onu-e-odesenvolvimento. aspx>. Accessed 14 June 2012. Pini Web (2012) Prêmio PINI. http://revista.construcaomercado. com.br/negocios-incorporacaoconstrucao/112/artigo190591-1.asp. Accessed 28 February 2012. Vigon, B Wet al (1995)Life Cycle Assessment: Inventory Guidelines and Principles. Cincinnati: U. S. Government Printing Office.

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Integrating LCA in the selection of strategies for reducing the energy demand in Mexican social housing Ileana Cerón-Palma1,2* – Esther Sanyé-Mengual1 – Jordi Oliver-Solà1,3 – Juan Ignacio Montero1,4– Joan Rieradevall1,5 1

SosteniPrA

(UAB-IRTA-Inèdit).

Institute

of

EnvironmentalScience

and

Technology

(ICTA),

UniversitatAutònoma de Barcelona (UAB), 08193 Bellaterra, Barcelona, Spain . 2

Inèdit. IneditEcoinnovación e Investigación Ambiental S de RL de CV. Mérida, Yucatán, México.

Phone: +34 93 581 37 60 E-mail: [email protected] URL: http://www.ineditinnova.com , http://www.sostenipra.cat 3

Inèdit Innovaciós.l.,carretera de Cabrils Km2, 08348,Cabrils (Barcelona),Spain.

4

Institute of Research and Technology in Agrifood Sector (IRTA), 08348 Cabrils, Barcelona, Spain.

5

Chemical Engineering Department, UniversitatAutónoma de Barcelona (UAB), 08193 Bellaterra,

Barcelona, Spain.

Abstract Currently, there are a large number of social housing units in Mexico being built in different regions, without considering the different climate conditions in the design of them. Therefore, there is an increase of the thermal demand due to long periods for cooling or heating the houses, thereby causing large energy consumption and emissions of CO 2 to the atmosphere. In this work, passive strategies are proposed for the sustainable rehabilitation of social housing in warm-humid climate settings with the objectives of selecting the best one by considering not only the thermal improvement but also the environmental impact associated with the materials used in each strategy. Four strategies were considered in this study: concrete wall overhangs, green roofs, aluminum windows louvers and jute fiber awnings for shading. The environmental assessment was performed using the Life Cycle Analysis (LCA) methodology according to ISO 14040 and following the ReCiPe method for the classification and characterization steps. According to previous works, the energy savings of the strategies were considered in the analysis. A balance of the potential cooling systems savings and the potential environmental impacts of the passive infrastructure was done to carry out the selection of the more environmentally friendly strategies. The jute fiber awning produced the greatest thermal savings (2,600 kWh/year) and was the most environmentally friendly option for 11 of 17 endpoint categories analyzed. The green roofing (1,231 kWh/year) and the aluminum windows louvers (1,054kWh/year) also showed significant savings of energy demand. However, they were the most impacting strategies from the environmental point of view. Finally, concrete wall overhangs had low energy savings and didn‘t show significant environmental savings. The integration of LCA in the decision-making process showed a complete analysis of the strategies not only from the energy but also from the environmental point of view. Key words: Social housing, LCA, Mexico, thermal comfort, sustainability.

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Introduction Cities use over 75% of the world´s resources (Pacione, 2009) and they are responsible for 75% of the world´s energy consumption and 80% of greenhouse gas (GHG) emissions (Ash et al. 2008).Latin America and the Caribbean (LAC) is the most urbanized region in the developing world with 80% of its relatively young population living in cities (UNFPA, 2007). Quality of life in these countries is affected by the rapid deterioration of the urban environment, due to the degradation of the built environment and the contamination or depletion of natural resources (Bolay et al. 2005). These problems are caused by urban development and population growth. In developed countries, residential and commercial buildings account for nearly 40% of all carbon emissions and consume as much as 73% of electricity (DAC, 2011).The Intergovernmental Panel on Climate Change (IPCC) estimates that by 2030, greenhouse gas (GHG) emissions from buildings will account for over one-third of total emissions (Levine et al. 2011). This data explains the importance of implementing eco-innovative strategies and initiatives in the construction sector. In Latin American countries like Mexico, there has been a massive increase in housing construction. Social and economic housing is of greatest demand (Cerón-Palma, 2008), where a standardized prototype house is produced. However, the different climatic contexts weren‘t considered in the design, leading to poor indoor thermal conditions.

Goal and objectives In Mexico, there are a large number of social housing projects constructed in the last few years, which need to be studied in order to determine strategies for eco-rehabilitation. These studies will need to be conducted in order to quantify the environmental of such modifications. The incorporation of eco-rehabilitation strategies represents an important local and global action to reduce energy consumption, lower the associated CO2 emissions and improve the quality of life of people living in these houses. The purpose of this study is to evaluate passive strategies for the sustainable rehabilitation of social housing in warm-humid climate settings with the objectives of quantifying the energy savings as well as the environmental impact associated with the materials used in each strategy.

Method Study system

An eco-rehabilitation study was developed using a standard social housing unit, representative of the current social housing landscape in Mexico. The social house consists of a single floor of 56 m2, which is inhabited by four people. The house is divided into four zones: adult´s room, children‘s room, bathroom and a living-dining area that includes a kitchen. The construction system is based on conventional materials, such as concrete block walls, joist and slab coverings.

FIGURE 1: CHARACTERISTIC OF STUDY SYSTEM Definition of strategies

The scenarios were obtained from Cerón-Palma et al. (2012) Scenario A: concrete overhangs in walls For this scenario, concrete overhangs in the eastern and western walls with a thickness of 0.10 m at a height of 2.20 m were considered. The main variable was the projection length of the overhang, which was 0.30, 0.50 and 0.70 m in scenarios A1, A2 and A3, respectively. The volume of concrete employed in scenarios A1, A2 and A3 were 0.41, 0.69 and 0.96 m3, respectively. Scenario B: overhangs and window louvers. Overhangs that are 0.50 m wide, extending to the same length from both sides to form an 235


aluminium frame above the windows, were considered. Four aluminium slats were considered with an inclination of 15º, a depth of 0.20 m and a placement of 0.30 m from the window glass. In total, 88 kg of aluminium were needed cover the seven windows of the house. Scenario C: green roof The scenario consisted of conventional and extensively green roof of 50 m2. The treatment included water-proofing and anti-root protection, a geotextile layer, a drainage layer, a filtering layer and a vegetation substrate totalling 0.20 m in height. Scenario D: Shade with a jute fabric awning. A shade made of jute fabric was proposed to be placed 0.35 m above the cover. The main variables of this scenario are related to the extension of the shade: D1, perimetric shading; D2, perimetric shading + 0.50 m of extension; and D3, rectangular shading

Energy savings and environmental assessment

The energy savings of the 4 strategies defined were obtained from Cerón-Palma et al. (2012).The environmental impact was evaluated through the Life Cycle Assessment method (ISO, 2006). Classification and characterization steps followed the ReCiPe method (Goedkoop et al., 2009) and the impact potential indicators were evaluated at endpoint level. The environmental assessment was performed for the construction (raw materials) and use (energy consumption) phases of the lifecycle and the lifespan of the different materials was considered (Cerón-Palma et al., 2012).

Results and discussion The proposed strategies showed reductions in the energy demand from 2600 to 359 kWh·year -1 (Table 1) (Cerón-Palma et al., 2012). According to these results, the jute fabric (D3) would be the best strategy, followed by the green roof (C). TABLE 1: ENERGY SAVINGS OF EACH PASSIVE STRATEGIES AND RANKING (FROM BEST – 1, TO WORST – 8), OBTAINED FROM CERÓN-PALMA ET AL. (2012). ENERGY SAVINGS RANKING (KWH) A1 359 8 A2 410 7 A3 499 5 B 1054 3 C 1231 2 D1 490 6 D2 1040 4 D3 2600 1 However, when the environmental impact of the materials is analyzed, the classification of the strategies varies (Figure 2). Considering the results from the LCA at endpoint level, the concrete overhangs scenarios (A1 and A2) showed the best profile, while green roof (C) and aluminum (B) strategies were the most impacting ones. Therefore, analyzing the energy savings and the environmental impact separately doesn‘t indicate the best and the worst option.

236


FIGURE 2: ENVIRONMENTAL IMPACT POTENTIAL FOR THE STRATEGIES, RANKED FROM LEAST (IN, 1) TO MOST (OUT, 8) IMPACTING. In this sense, the values were combined to obtain the environmental impact per saved energy (kWh) (Table 2). The results showed that the jute fiber strategies are the best options (especially D3 and D2) as they have great results in energy savings but not large environmental burdens. These strategies showed the lowest environmental impact in 11 out of 17 categories, apart from climate change (ecosystems), ionizing radiation, terrestrial and freshwater ecotoxicity, human toxicity and agricultural land occupation, categories where strategy A (concrete) had better results. However, if only the environmental results are considered, strategies D2 and D3 would only be at 5th or 6th position. Strategies C (green roof) and B (aluminum overhangs) had so large environmental burdens that remain the worst options although having good results in energy savings. Finally, concrete wall overhangs (strategy A) are placed in the middle of the list as they were the worst option regarding the energy savings although being the best from the environmental point of view (Figure 2). TABLE 2: CLASSIFICATION OF PASSIVE STRATEGIES: FROM BEST (1) TO WORST (8), BY ENERGY SAVINGS (CERÓN-PALMA ET AL., 2012), BY TOTAL ENVIRONMENTAL IMPACT AND ENVIRONMENTAL IMPACT PER SAVED KWH (ENDPOINT LEVEL). ENERGY ENVIRONMENTAL ENVIRONMENTAL

A1 A2 A3 B B D1 D2 D3

SAVINGS

IMPACT

IMPACT PER SAVED KWH

8 7 5 3 2 6 4 1

1 2 4 7 8 3 6 5

3 5 6 7 8 4 2 1

The integration of LCA in the classification of the strategies was a key step for selecting the best strategy while considering a global environmental profile. Therefore, strategies B and C that showed large energy savings were identified as the worst environmental options regarding the materials used. Moreover, the low environmental impact of jute fiber (D) supported the selection of this strategy as the best option for improving the thermal conditions.

237


Conclusions The integration of the strategies and methodologies presented in this study showed a complete analysis of the environmental benefits of the passive structures for improving thermal conditions analyzed. Therefore, studies that include LCA in the assessment of passive thermal strategies could result in a complete environmental analysis for the selection. Moreover, these studies could provide an economic driver for the transformation of existing social housing by integrating environmental criteria and life cycle analysis for system evaluations and decision making. Similarly, the results of this study can contribute to improvements in the competitiveness of developing new housing, when these strategies and methodologies are integrated from the design stage. We expect that the methodology of this work will allow other investigators and designers to apply similar studies to other climatic regions.

References Ash, C., Jasny, B.R., Roberts, L., Stone, R., Sugden, A (2008). Reimagining cities ‐ Introduction. Science. 319(5864):739‐739. Bolay, JC.,Pedrazzini, Y., Rabinovich, A., Catenazzi, A. and Garcia-Pleyan, C (2005). Innovations in the Urban Environmental and Social Disparities in Latin America: The Shift from Technical to Social Issues as the True Challenge of Change, Habitat International 29: 627–645. Cerón-Palma, I (2008).Evaluación de Factores de Confort y contaminaciónambiental en la viviendaeconómica de climacálido-húmedo. Master disertación. Facultad de Ingeniería. Universidad Autónoma de Yucatán. Ceron-Palma I, Oliver-Solà J, Sanyé-Mengual E, Montero JI, Rieradevall J (2013) Towards a green sustainable strategy for social neighbourhood in Latin America: Case from social housing in Merida, Yucatan, Mexico. Habitat International, 38: 47-56, in press / DAC (2012).Building and sustainable cities.Danish Architecture Centre, Copenhagen.. Accessed 29.09.12 Goedkoop MJ, Heijungs R, Huijbregts M, De Schryver A, Struijs J, Van Zelm R (2009) ReCiPe 2008, A life cycle impact assessment method which comprises harmonised category indicators at the midpoint and the endpoint level; First edition Report I: Characterisation. Available on http://www.lcia-recipe.net. Accessed 20 October 2012. ISO (2006) ISO 14044:2006 Environmental management -- Life cycle assessment -- Requirements and guidelines.International Organization for Standardization, Geneva. Levine, M., D. Ürge-Vorsatz, K. Blok, L. Geng, D. Harvey, S. Lang, G. Levermore, A. MongameliMehlwana, S. Mirasgedis, A. Novikova, J. Rilling, H. Yoshino, (2007). Residential and commercial buildings. In Climate Change 2007: Mitigation. Contribution of Working Group III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change [B. Metz, O.R. Davidson, P.R. Bosch, R. Dave, L.A. Meyer (eds)], Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA. Accessed 17.05.12. Pacione, M (2009). Urban geography. A global perspective. Oxon (UK): Routledge. UNFPA (2007).State of the world population.Accessed 29.09.12.

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Comparative Life Cycle Assessment of a Retrofit Housing Project and a Suburban Housing Development in the Metropolitan Area of Mexico City Ariadna Reyes* – Ricardo Ochoa – Louise Guibrunet Centro Mario Molina, Prolongación Paseo de los Laureles No. 458, Despacho 406 Col. Bosques de las Lomas, Cuajimalpa, C.P. 05120, México, D.F.

++52 55 91771670 Fax ++52 55 91771690 [email protected] URL: http://www.centromariomolina.org

Abstract This article presents the preliminary results of the Life Cycle Assessment (LCA) of two types of government-financed social housing present in the Metropolitan Area of Mexico City: On the one hand, a flat within an urban retrofit project, and on the other hand, a suburban terraced house. The environmental performance of these households will be compared based on these results. It was found that the urban retrofit unit has a better environmental performance than that of the suburban one. The key factor is the location. An urban location makes an efficient use of the existing urban land (instead of requiring land use conversion). In addition to this, the location facilitates the reduction of the fossil fuel consumption for private transport, provided that there is an adequate access to efficient public transport facilities (Metro, Bus Rapid Transit, and Tramway).Another important factor in the environmental performance is the construction of infrastructure and the installation of technologies which reduce the water and energy consumption.

Purpose To compare the environmental performance of a suburban housing development with that of an urban retrofit project, both being located in the Metropolitan Area of Mexico City.

Introduction The housing sector is the driving force of the development of Mexican cities. The need to foster economic growth and to provide for the great demand for middle-class housing has led the federal government to launch a National Programfor Housing in the year of 2007 (CONAVI, 2008), which has enabled and promoted housing development at a massive scale. As a result, in the last presidential term (2006-2012), 5.8 millions of families have received a government credit to buy a newly constructed house. These government-financed houses share many characteristics, be it in their constructive mode or effective use: because they are constructed with an objective of timeand cost-efficiency, they are usually located in the periphery or outside the periphery of cities where the land is the cheapest (but public transport is scarce). The houses are small (59 m2) but are often equipped with a garden and a parking space, and are constructed as single use residential complexes, with private access only. This pattern has two main consequences: First, the lack of non-residential uses in these developments means that the population has to move to access any kind of public service, activity or commodity. Considering the peripheral location and the lack of public transport in these areas, this means that this model is directly fomenting the intensive use of the car. Secondly, the horizontal construction (ground floor houses) in the periphery is inefficient 239


in terms of land use, because it does not make use of available urban land, and requires converting agricultural land for the purposes of construction: As a result, the expansion of Mexican cities is 3.5 times greater than the population growth (ONU HABITAT and SEDESOL, 2011) In Mexico, the housing sector accounts for 16% of total energy consumption and 9% of total greenhouse gases (GHG) emissions26(Trejo, 2010)as such, the environmental performance of the sector has to be monitored and improved if Mexican GHG emissions are to be reduced. The important share of government-financed housing in the construction sector means that it is essential to specifically assess its environmental performance, which can be measured by carrying out a Life Cycle Assessment (LCA) focused on both the constructive mode of the house and the use given to it by the user. This article presents the preliminary results of the Life Cycle Assessment of a house in a suburban housing development27 in comparison to that of a flat in an urban retrofit28; both households being located in the Metropolitan Area of Mexico City. Table 1 presents the main characteristics of both types of households.

Table 1: Urban and architectural characteristics of both types of households Characteristics

Urban unit

Suburban unit

Location

Urban (industrial zone) with Rural in access to public services suburban Accessibility to transport Metro, Bus Rapid Transit, Car Tramway Distance to the closest 1 km 26.6 km metro station: Average daily commute

1.06 hours

2.08 hours

Land use

Mixed-use

Residential

Living area per household 70m2

59m2

Constructed area per household 36.95 m2 (house and urbanization)

179.31 m2

Floor area ratio* Building type Building height Price (Mexican pesos) Inhabited since Water management systems

Energy-efficient technologies

transition

to

0.51 3.54 Renovated Flat New terraced house 5 floors (20 flats) 1 floor 689,000 400,000 - 650,000 2011-2012 2006 Rainwater recovery, water Municipal supply and treatment of treatment and re-use on-site, residual water permeable pavements Solar water heaters, photovoltaic None public lighting

*The floor area ratio is the total constructed area (on all floors) divided by the plot area.

Methodology The following environmental impact categories were selected for their relevance in the life cycle assessment applied to buildings: acidification, global warming, ecotoxicity, eutrophication and human toxicity. The LCA was carried out for the stages of pre-use: extraction of materials, transportation of materials, construction; and use (which includes the maintenance of the building). 26

This is excluding the emissions of the transport sector, which are inextricably linked to the residential sector and patterns of urban development. 27 For the purpose of clarity, in this article, ―the house‖, ―the suburban unit‖, and ―the suburban development‖ will be used equally to refer to the suburban development. 28 For the purpose of clarity, in this article, “the flat”, “the urban unit”, and “the retrofit project” will be used equally to refer to the urban retrofit project. 240


In the case of the urban retrofit, the materials of the previous construction were not considered because the retrofit takes advantage of existing constructions that were sub-utilized and abandoned; nonetheless, the materials required for the renovation process were taken into account. For the use stage, a lifespan of 50 years was considered. This period is based on the most common approaches in LCA in buildings (Ramesh et al., 2010) and (UNEP, 2007), which enables comparison with other investigations. It was considered that a household (subject of the LCA) includes the following subsystems: a) the house as an edification, b) the urban section—main and secondary roads, sidewalks, pipelines, etc.—, c) infrastructure works—absorption wells, treatment plants, etc.— and d) resource consumption and emissions related to the use and maintenance of the household. The environmental impacts of the elements related to the household‘s life cycle were estimated regarding the functional unit: one square meter of habitable household in a 50 years lifespan. The openLCA 1.2.6 program was used to process the inventories of LCA and, the selected method was CML 2001. This study included environmental impacts found in previous LCA studies of products made and used in Mexico (for example asphalt obtained in the Metropolitan Area of Mexico City), and the reference database was the US-based National Renewable Energy Laboratory (NREL). The flows of energy, water, materials and resources of the pre-use stage were defined through direct information from Mexican housing developers who provided plans and databases that itemize the consumption of construction materials and earth-moving machinery. The flows of energy, water, materials and resources of the use and maintenance stage were obtained through the conduction of surveys on 3,817 residents, the results of which were analyzed to obtain statistically representative information. The LCA inventory of the suburban household is representative of suburban developments in the study area; on the contrary, that of the urban retrofit is based on a case study, as such it cannot be considered representative of other similar developments.

Results and discussion Figure 1: Comparison of the units‘ environmental impacts Acidification kg SO2−Eq

15 10 5 0

Climate Change kg CO2−Eq

3000 2000 1000

Ecotoxicity kg 1,4−DCB−Eq

LCA Category

0 20 15 10 5 0

Pre−use Use

Eutrophication kg PO4−Eq

400

Stage

300 200 100 0

Human toxicity kg 1,4−DCB−Eq

10000 5000 0 Suburban

Urban Retrofit

Household type

Figure 1 shows the environmental impacts occurring in the pre-use and use stages for both types of households per LCA category —acidification, global warming, ecotoxicity, eutrophication and human toxicity—, measured in kg of their equivalent units. 241


The main differences in the environmental impacts are the water consumption, urbanized land, gasoline, electricity and gas; and to a lesser extent the consumption of construction materials. Table 2 shows the main flows of natural resources per square meter of habitable household in a 50 years lifespan. Table 2: Comparison of flows of energy and resources per square meter of habitable household in a 50 years lifespan. Flow

Stage

Urban retrofit

Suburban household

Cement Steel Water Gas Electricity Gasoline Diesel

Pre-use Pre-use Use Use Use Use Use

121 kg 34 kg 131 m3 0.07 m3 1230 kWh 187 liters 30.8 liters

151 kg 18 kg 413 m3 0.43 m3 1610 kWh 250 liters 10 liters

The suburban unit generates higher emissions in all LCA categories, particularly in global warming, for which overall emissions are 67% higher than that of the urban unit, with 3533 kgCO2eq and 2120 kgCO2eq; respectively. Similarly, the overall emissions of the suburban unit are 35% higher than that of the urban one for the rest of LCA categories (ecotoxicity, eutrophication and human toxicity); as for acidification, the impact of the suburban house is 43% higher than that of the urban flat.

Water consumption The management of residual water contributes to the most to the categories of ecotoxicity, eutrophication and human toxicity with 94%, 100% and 96% for both types of households. However, there are remarkable differences in the consumption of water, with the house requiring 413m3, and the flat only 131 m3 (due to the incorporation of systems that reduce the water consumption in the retrofit development).While in the retrofit development, 21% of the water is treated on-site and re-used; in the suburban development, the residual water (which represents 80% of the water consumed) is sent to the municipal treatment facilities; which have an estimated capacity to treat only 14% of the total residual water in the study area.

Urbanized land The differences in land use are significant, considering that the urban flat requires only 36.95m2 of urbanized land while the suburban house requires 179.31m2. The efficient land use (that is to say, building dense and urban developments) reduces the environmental impact of the unit by avoiding earthworks and by preserving rural land uses. The distribution of land use in the case studies is represented in Figure 2. Figure 2: Distribution of land use in both units

242


It is interesting to note that a higher housing density reduces the resources and space spent on roads: as one can see in Figure 2, roads represent only 5% of the plot in the case of the urban retrofit project (which has a floor area ratio of 3.54). On the other hand, in the case of the suburban development (which has a floor area ratio of 0.51); roads represent 26% of the total plot. This difference in density represents an opportunity for the developer to devote more land to green spaces or common areas: In the retrofit project, 26% of the land is used as green spaces, while in the case of the suburban development, there are no green spaces.

Gasoline and Diesel Private transport is the second highest impact contributor in the life cycle assessment, as it is responsible for 21% and 22% of CO2eq emissions for the urban and suburban units, respectively. The gasoline consumption for private transport accounts for 187 liters in the case of the urban unit and 250 liters in the case of the suburban one.The diesel consumption is mainly related to public transport activities (Bus Rapid Transit, buses, etc.). It was found that the urban retrofit requires a higher consumption of diesel with 30.81liters while the suburban consumes only 5.9 liters.

Electricity The electricity consumption accounts for 50% and 42% of the overall life cycle CO2eq emissions for the urban and suburban households. It also contributes to the 74% of the overall SO2eq emissions in the case of the urban household and 72% in the case of the suburban one. Nonetheless, there is an electricity consumption of 1230 kWh and 1610 kWh in the urban and suburban units, respectively. In the case of the retrofit project, it is worth noting that 20% of the public lighting is solar-powered.

Gas The implementation of solar water heaters instead of conventional boilers in the urban flat explains that the gas consumption is 83% lower than that of the suburban house (0.43m3 and 0.07m3). The gas consumptionis the third highest contributor of CO2eq emissions, with 20% of total emissions in the suburban household (followed by the electricity consumption and private transport), and 5% of total emissions in the case of the retrofit.

Construction materials The manufacture of cement generates the most emissions in the pre-use stage. It accounts for 37% of total CO2eq emissions in the case of the urban unit and 43% in the case of the suburban one (followed by steel with 25% and 14% of total emissions, respectively).The urban retrofit unit requires almost as many construction materials (cement and steel) as a new suburban house, because of the heavy use of permeable concrete for pavements and the construction of infrastructure to enhance water storage in cisterns and storm tanks, among others.

Pre-use and use stages The use stage is the most important in terms of emissions for all LCA categories. It is evident that the impact of the pre-use stage is minimal compared to that of the use stage for both types of households, for the following LCA categories: ecotoxicity, eutrophication and human toxicity. The pre-use category only demonstrates considerable impacts in the global warming category. With respect to the urban flat, this stage accounts for 14% of CO2eq emissions; whereas for the suburban house, it accounts for 8% of these emissions. Similarly, the impacts of the pre-use stage for both types of households account for 3% of the overall acidification.

Conclusions The main finding of this research is that a retrofit project has a lower environmental impact than a new suburban development, as it makes a more efficient use of the existing urban land, takes advantage of existing structures, and integrates resource-efficient technologies that reduce the resource consumption of the residents. To conclude, the life cycle assessment is a comprehensive tool that identifies opportunities to better the environmental performance of housing developments. It is especially powerful and relevant if used during the design stage (before the process of construction even starts), as it enables a more informed decision-making process with respect to the key design aspects of the 243


development (the location of the development, or the construction of resource-efficient systems, for instance). It is interesting to note that a parallel study focusing on the social aspects of these two types of housing has shown that the urban unit fares better in terms of quality of life than the suburban one. This is mainly due to the availability of urban infrastructures, services and public transport (which reduces drastically the daily commute), as well as the quantity and quality of green spaces and public places available within the development. As such, there are social arguments as well as environmental ones in favor of the reorientation of the production of social housing towards urban retrofit projects and away from suburban constructions —the social aspect of housing being an essential one in the Mexican context due to high vacancy rates in suburban developments.

References CONAVI (2008) Programa Nacional de Vivienda 2007-2012: Programa Nacional de Vivienda 2007-2012: Hacia un Desarrollo Habitacional Sustentable, México, D.F. ONU HABITAT & SEDESOL (2011) Estado de las Ciudades de México, México, D.F. RAMESH, T., PRAKASH, R. & SHUKLA, K. K. (2010) Life cycle energy analysis of buildings: An overview. Energy and Buildings, 42, 1592-1600. TREJO, V. I. (2010) Balance Nacional de Energía y su Relación con el Inventario de Emisiones Realidad, Datos y Espacio. Revista Internacional de Estadística y Geografía. México, D.F., INEGI. UNEP (2007) Buildings and Climate Change: Status, Challenges and Opportunities. IN DTIE, U. (Ed. 15 Rue de Milan 75009 Paris, Francia.

244


Comparative evaluation of brt (bus rapid transit) and lrt(light rail transit) systems: life cicle simulation using the gabi software tool GuilhermePedroso* - CláudiaEchevenguá Teixeira**- Oswaldo Sanchez Júnior*** *GP Engenharia S/S Ltda., Rua Guadalajara n. 817, Sala 1, Caieiras, Centro, CEP 07700-000, São Paulo, Brasil,+55 11 99592 7922, [email protected]; **

Instituto de Pesquisas Tecnológicas do Estado de São Paulo – IPT, Av. Prof. Almeida Prado, 532, Cidade

Universitária, Butantã, São Paulo, CEP 05508-901, São Paulo, Brasil, +55 011 37674151, [email protected], URL: http://www.ipt.brand Universidade Nove de Julho, Programa de Mestrado e Doutorado em Administração. Av.: Francisco Matarazzo, 612 - Prédio C- 2º Andar, Água Branca, São Paulo, CEP 05001100, São Paulo, Brasil, +55 011 36659351 URL: www.uninove.br/pmda; ***Instituto de Pesquisas Tecnológicas do Estado de São Paulo – IPT, Av. Prof. Almeida Prado, 532, Cidade Universitária, Butantã, São Paulo, CEP 05508-901, São Paulo, Brasil, +55 011 37674588, [email protected], URL: http://www.ipt.br.

Abstract Objective: to evaluate the applicabilityof theLife Cycle Assessment (LCA) technique to comparethe environmental performance oftwo means ofurbantransport: Bus Rapid Transit (BRT) and Light Rail Transit (LRT). Methods: it was defineda scopefor the study, a common functional unit and conducted an inventoryofmass and energyflows.After reviewing theinventories, simulations were conducted to analyze theimpacts ofboth systems bymodeling them with the CML 2001 and Ecoindicator 99. Results: Based on the conclusions developed within the limits of this study, it can be stated that: VLT has a better response to environmental indicators of acidification, eutrophication, depletion of nonrenewable natural resources and respiratory diseases while both systems shown greenhouse gas emissions in quite similar quantities. Conclusions: The technique of LCA is applicable as a tool for decision support on urban transit specifications and also to assist designers in the transportation sectors aiming to choose appropriate equipment and materials to mitigate environmental impacts. Keywords: LCA for Urban Transport; BRT System; LRT System.

1. Introduction The concept of sustainability is not so different from the general one, when the analysis is focusing urban transports systems even though they are quite complex structures. According to GOLDMAN and GORHAM, 2006, technical experts from this sector basically adopt two approaches regarding this sustainability concept. One of the approaches establishes that sustainability for such systems is a path that forces defined indicators and their associated parameters to be continuously monitored. So, a given system is then considered sustainable whenever improvements are detected along the time. The other approach also uses indicators, but they are taken as target to be reached: then, a given system is considered sustainable once a 245


defined target is reached. The authors under reference shows as examples for these two approaches the Environmentally Sustainable Transport (EST) Project, developed by the OECD (Organization for Economic Co-operation and Development), that follows the first philosophy and the Centre for Sustainable Transport (CST), from Toronto, which adopts the second approach. Indicators and parameters with proper metrics make possible quantitative assessments on sustainability studies. These quantitative assessments are useful for decision makers and can also provide set points and or targets to be taken as references for monitoring and controlling actions willing to improve systems or processes. Examples of specific sustainability indicators applicable for urban transit systems are shown on following cases. COSTA et al, 2004, adopts a set of indicators and parameters classified as: transport and environment; management of the urban mobility; land management and transportation demand; and social-economics aspects; RODRIGUES, 2008, made a quality analysis of the bus transportation system of the city of Uberlândia (Brazil) using the following indicators and parameters: level of accessibility; vehicle frequency (headway); trip time; system reliability; system safety; vehicle conditions; conditions of the stations; presence of passenger information system; level of connectivity; quality of passenger attendance; and conditions of the rolling lanes. A third example, a case treated by CATANHO, 2009, efforts were dedicated to study the environmental impacts and the operational performance of the bus transit system so named ExpressoTiradentes, located in São Paulo (Brazil): local environmental impacts; capacity of the system to mitigate impacts over the urban environment; level of quality maintained for the urban environment. On another case, CAMPOS and RAMOS, 2005, adopted indicators targeting to evaluate and promote the urban sustainability considering environment impacts, economic aspects and social indicators direct associated to the use of the land.

Scope and Objective Comparison BRT X LRT Functional Unit System Boundary Elementary processes Elementary Reference Flows Life Cycle Phases

Inventory Assessment along the life cycle phases Elementary Processes – Data Collection Inputs – Energy and Materials Products, co-products and discards Emissions to: air, water and soil

Interpretation Analysis and comparison of the impacts assessed for both systems (BRT and LRT)

Impacts Evaluation Category of Impact - Definition Selection of Indicators and Metrics Selection of Models for Characterizations Estimation of impacts according to the indicators and metrics

LCA

Figure 1. Steps for evaluation of Product Sustainability – LCA Source: Authors, adapted from NBR ISO 14044:2009 Life Cycle Assessment (ABNT NBR ISO 14040/14044:2009) was the method used on the assessment explained on this paper (Figure 1). This is an approach that follow systematic steps that takes care of: making clear the objective of the assessment; defining the scope of the assessment by selecting proper unit processes and elementary product flows to be assessed; performing the inventory assessment (mass and energy present on each product flow); definition of indicators, parameters and metrics, elements which are the basis for quantifications of parameters to make possible the main objective of this study (to do effective product/system comparisons); impact assessment; and finally impact interpretation of the results. In order to start designing the unit process and elementary product flows, it was defined a common basis or, in other words, a common macro specification for the two transportation systems under analysis. This common basis is so named Functional Unit by the LCA standard (ABNT NBR ISO 14044:2009). The assessment of environment was done running simulations with the GaBi Software considering the CML 2001 and the Ecoindicator 99 models (FRISCHKNECHT et al, 2004). 246


2. Case of study The case of study is a comparison of environmental impacts produced by two urban transportation systems. One is the Bus Rapid Transit (BRT) and the other is the Light Rail Transit (LRT). BRT is a urban mass transportation system of medium capacity, serving in average 20.000 passengers per hour per direction. Vehicles are buses with internal capacity for 190 people, operating on exclusively or partial exclusively dedicated road corridors. And LRT is a system that has the same general operating approach of the BRT in the sense to be a medium capacity transit corridor, but has railway types of vehicles as well as track infrastructure (Authors, adapted from VUCHIC, 2007). 2.1 Functional Unit

The Functional Unit defined for the assessment herein described has the following characteristics (PEDROSO, 2012): a people transportation lane corridor with 20 km of extension located in São Paulo (Brazil); transportation capacity is a minimum of 1500 passengers per hour per direction; minimum commercial speed of 20 kph; comfort level of 4 passengers per m2 inside the vehicles; vehicles can be either buses propelled by internal combustion engines using diesel fuel or electrical railway rolling stock equipped with electrical motors; the electricity to be used for vehicle propulsion is generated by hydroelectric power plants; system life cycle should be 30 years; assessment should be done according to the five phases, as described into the LCA standard. 2.2 Systems Boundary

Both systems, BRT and LRT were modeled using the standard definition of Product System as per the LCA standard: Product System is a ―collection of unit processes with elementary and product flows, performing one or more defined functions, and which models the life cycle of a product.‖ The BRT Reference flow was defined as having two unit processes: the vehicle itself and the roadway infrastructure, as shown on Figure 2. And the Reference Flow for the LRT system, as shown on Figure 3, has four unity processes: vehicle, railway, catenary and power substations. System Boundary

Product Flow (Materials)

Product System Rolling-stock (BRT Vehicle) Unit Process 1

Product Flow (Products)

Energy Process

Product System Roadway Infrastructure

Products and Emissions

Unit Process 2 Water Process Product System BRT

Figure 2. BRT Reference Flow - Source: Authors

247


Product System Rolling-stock (LRT Vehicle) Unit Process 1

Product Flow (Materials)

Product System Railway Infrastructure

Product Flow (Products)

Unit Process 2

Energy Process

Products and Emission s

Product System Catenary Hardware Unit Process 3

Water Process

Product System Power Substation Hardware Unit Process 4 Sistema VLT

Figure 3. LRT Reference Flow - Source: Authors

2.3 Inventory Assessment

Theinventorycanbe summarizedby thefollowing tablewhereit can be seenmainly,in bold, the unfavorableflows. Table 1. Inventory Assessment. Source: Authors. 20 20 kmdouble track 4 power kmCatenar infrastructure substation y

vehicles Materials

unit 40 vlp

10 vlt

vlp

vlt

vlp vlt

4.951.920 na

vlp vlt

300.40 na 0

6.000

484.240.0 505.866.6 na 00 66

na

na

na

0

na

na

na

na

na

na

14.000

0

na

na

na

na

na

na

Renewable MW electric energy

10.660

1.051.202.6 nd 00

nd

na

nd

na

nd

Diesel oil

lt

175.200.0 5.000 00

1.914.058 1.998.000 na

nd

na

650

Water

lt

17.302

15.614

nd

na

nd

na

nd

kg

1.156.565 81.150

0

0

na

0

na

0

kg

191.568

0

0

na

64.000 na

Metals

kg

894.712

374.605

0

Clay/gravel /sand/asphalt

kg

0

0

New tires

pç

7.000

Retreads

pç

Waste(landfill /incineration) Other materials

4.642

65.120

40.928

248


2.4 Impact Evaluation

The LCA indicators selected for this study for the environmental assessment are shown on Table 2 Table 2. Indicators and Parameters - Source: Authors Environment Dimension Scope

Global

Indicator

Parameters

Global Warming

Emissions of: CH4, CO2

Depletion of natural resources

Metrics

Depletion of fossil fuel Depletion of iron ore Emissions of CO

Local and Regional

Air pollution

Acidification / Eutrophication

Emissions of Material (PM))

Mass Unit particulate

Emissionsof: NO2,SO2, VCO, PO4, N2, N2O, NO3, NOx

The GaBi Software was configured to run the two systems (BRT/LRT) which were modeled into the GaBi environment. Impacts were simulated using: the Ecoindicator 99 (EI99) modeling with Brazilian matrix for energy; and the CML 2001.

3. Results Table 3 has the results obtained out of the simulations and Figure 4 shows these numbers on a graphical format. Table 3. Results of the GaBi simulations – Source: Authors Results Model

CML 2001

Ecoindicator 99 (EI99)

BRT Emissions: Phase of Use: GHG (100 years effect) 13,40 e-5 Emissions: Phase of Use: Acidification 2,60 e-5 Euthrofization 2,40 e-5 Natural Res. Depletion (Minerals) 2,85 e-5 Ozonization 1,85 e-5 Emissions: Phase of Use: Human Health Respir. (Inorganic 11,50 e+6 Human Health Climatic Change 3,00 e+6 Natural Res. Deplet. (Fossilfuel) 21,00 e+6 Acidification 1,80 e+6

LRT Emissions: Phase of Use: GHG (100 years effect) 19,00 e-5 Emissions: Phases of Production, Rec. and Use: Acidification 0,056 e-5 Euthrofization 0,184 e-5 Natural Res. Depletion (Minerals) 0,206 e-5 Ozonization 0,070 e-5 Emissions: Phases of Production and Use: Human Health Respir (Inorganic) 1,75 e+6 Human Health Climatic Change 3,70 e+6 Natural Res .Deplet. (Fossilfuel) 0,80 e+6 Acidification 0,00 e+6

249


Figure 4. Results of the GaBi simulations – Source: Authors Based on the assessment done within the defined systems boundaries, it is possible to say that: the LRT has better response to the environment indicators of acidification, eutrophization, consumption of natural resources (minerals and fossil fuels), ozonization, and effects on human health due to emissions of inorganic particles. The other two indicators, GWP 100 years and effects on human health due to climate changes are a little in favor of the BRT. The interpretation for this scenario is that the Functional Unit has defined that all electricity consumed by the two systems are generated by hydroelectric power plants. As proper for these power plants, especially the ones located in a tropical region, which is the case for Brazil, they produce emissions of carbon monoxide and methane gases (STEINHURST, 2012). As general recommendations for the designers of both systems: - the BRT has definitively to invest in alternatives for the fossil fuel propelled diesel engines of the vehicles (assumption taken on this study); fossil fuels emissions are also bad for the human health regarding respiratory diseases (inorganic particulate emissions); another point is to increase the life cycle of the vehicles, herein considered as been 15 years (against 30 years for the LRT vehicle), action that has direct effects on reducing the depletion of nature materials (specially mineral ones); - the LRT has to reduce the consumption of electric power during the phase of vehicles operation, even though this power is generated by hydropower; the reduction of this power consumption is direct associated with the weight of the vehicles (vehicle weights around 3 times more than a BRT one with the same transportation capacity).

4. Conclusions and envisaged applications The LCA technique is a good tool to support managers to take decisions when dealing with comparisons of urban transit modals. It is also important for designers of such systems, as a support to help them choosing equipment and materials proper to mitigate environmental impacts regarding manufacturing, installation and operation of rolling stock and trackside devices. The application of LCA on this case study has shown that both systems, BRT and LRT has pros and contras arguments, such arguments were quantified and possible to be used for improvements on both products and also possible to be used on management decisions whereas to adopt one or the other transportation means. Another outcome of this evaluation is that an interesting question can be made and then opening a possibility for this research to continue: any chance for a new system to exist, in between BRT and LRT that could incorporate the good characteristics from each one? Like for instance the monorail, a new modal just beginning to be applied for urban mass people transportation (this is the case of city of São Paulo, now installing two monorail systems) replacing BRTs and LRTs? Well, this is something to be answered after some proper simulations like the 250


ones done for the case herein described.

References ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS (ABNT). NBR ISO 14040: Gestão ambiental - Avaliação do ciclo de vida - Princípios e estrutura. Rio de Janeiro: ABNT, 2009. ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS (ABNT). NBR ISO 14044: Gestão ambiental - Avaliação do ciclo de vida - Requisitos e orientações. Rio de Janeiro: ABNT, 2009. BLACK, J. A. et al. Sustainable urban transportation: performance indicators and some analytical approaches. Journal of Planning and Development, v.128, n. 4, Dec. 1, 2002. Available at: . Access: 08 mar. 2011. CAMPOS, V. B. G.; RAMOS, R. A. R. Proposta de indicadores de mobilidade urbana sustentável relacionando transporte e uso do solo. Rio de Janeiro: UFRJ/COPPE, 2005. Availableat: . Access: 10 nov. 2009. CATANHO, M. G. Análise dos impactos ambientais e urbanos decorrentes dos investimentos em implantação ou operação de Sistemas BRT – Classe I (Transporte Rápido por Ônibus): o caso do Expresso Tiradentes em São Paulo. 2009. 201 f. Dissertação (Mestrado) - Instituto de Pesquisas Tecnológicas do Estado de São Paulo, São Paulo, 2009. COSTA, M. S.; SILVA, A. N. R.; RAMOS, R. A. R. Indicadores de mobilidade urbana sustentável para Brasil e Portugal. In: Planejamento integrado: em busca de desenvolvimento sustentável para cidades de pequeno e médio portes. Braga: Universidade do Minho, Departamento de Engenharia Civil, 2004. Availableat: . Access: 10 nov. 2009. FRISCHKNECHT, R. et al. The eco-invent Data base: Overview and Methodological Framework.International Journal of Life Cycle Assessment, Online First: October, 22nd, 2004. GOLDMAN, T.; GORHAM, R.Sustainable urban transport: four innovative directions. Technology in Society, v.28, p.261-273, 2006. HAGHSHENAS, H.; VAZIRI, M. Urban sustainable transportation indicators for global comparison.Ecological Indicators, Elsevier, v. 15, p. 115-121, 2012. JEON, C. M. et al.Addressing sustainability in transportation systems: definitions, indicators, and metrics. Journal of Infrastructure Systems, ASCE, p. 31-50, Mar. 2005. Available at: . Access: 8 mar. 2011. KATO, H.; SHIBAHARA, N.; WATANABE, Y.A systematic approach for evaluating public transport systems through LCA.INTERNATIONAL CONFERENCE ON ECOBALANCE, 7., 2006, Tsukuba, Japan. Proceedings… [S.l.; s.n.], 2006. Available at: . KLÖEPFFER, W.Life Cycle Sustainability Assessment of Products.International Journal of Life Cycle MAY, A. D. Achieving sustainable urban transport. Journeys, Nov. 2008. Available at: . Access: 8 mar. 2011. PEDROSO, G. Avaliação comparativa de sustentabilidade de sistemas VLP (Veículo leve sobre pneus) e VLT (Veículo leve sobre trilhos): um estudo exploratório. São Paulo, 2012, 189p. Dissertação (Mestrado em Tecnologia Ambiental - Gestão Ambiental) - Instituto de Pesquisas Tecnológicas do Estado de São Paulo. RODRIGUES, M. A Análise do transporte coletivo urbano com base em indicadores de qualidade. 81 f. Dissertação (Mestrado) - Faculdade de Engenharia Civil, UFU, 2008. SIMON B., TAMASKA L., KOVÁTS, N. Analysisof Global and Local Environmental Impactsof Bus Transportby LCA Methodologies. Hungarian Journal of Industrial ChemestryVeszprém, v.38, n.2, p.155–158, 2010. STEINHURST, W.; KNIGHT, P.; SCHULTZ, M.Hydropower Greenhouse Gas Emissions: State of the Research. Synapse Energy Economics, Inc. Cambridge, MA, Feb 14 th 2012. Available at . Access: 20 maio, 2012. VUCHIC, V. R.Urban transit – systems and technology. New Jersey: John Wiley & Sons, Inc. 2007. 251


Life Cycle Assessment of the Brazilian diesel consumption: Effects of sulfur reduction Moura, A S.1 - Caldeira-Pires, A. 2 - LUZ, S. M.3 - Frate, C.A. 4 1

Faculdade UnB Gama(FGA), Universidade de Brasília (UnB), Brasília, Brasil, 72444-240, e-mail:

[email protected] 2

Faculdade UnB Gama (FGA) - Universidade de Brasília (UnB), Brasília, Brasil,72444-240,e-

mail:[email protected] 3

Faculdade UnB Gama (FGA) - Universidade de Brasília (UnB), Brasília, Brasil,72444-240, e-

mail:[email protected] 4

Faculdade de Tecnologia - Universidade de Brasília (UnB), Brasília, Brasil, 72444-240,e-

mail:[email protected]

Abstract This study aims at assessing sulfur oxides environmental impacts associated with the production and consumption of Brazilian diesel. The analysis will address two diesel use context, namely before and after the Brazilian program Proconve, which implemented diesel 50ppm production and consumption.

Proconve (Portuguese acronym for ―Air Pollution Control from Motor

Vehicle‖) regulates the emission levels of pollutants from diesel engines, as well establishes limits of sulfur concentration in diesel, therefore aiming at reducing this pollutant concentration in high population density regions and the environmental impacts associated with sulfur oxides in urban and rural areas. In this context, this study compares the environmental impacts associated with the changes associated with production and use of diesel 50 and 2000 ppm sulfur content, for two different regions, rural and urban areas of the State of São Paulo. The study is based on secondary data from a typical refinery, as defined in a commercially available LCI database, and statistical data from production and use of diesel in the State of São Paulo, in the period before and after the creation of PROCONVE. The results demonstrate that PROCONVE succeeded in mitigate emissions in the urban area, after low sulfur diesel introduction, demonstrated by growth of just 3,3% in the period. In the rural area, on the other hand, the emissions grew by 20%, but basically due to increased consumption. In the urban area, Keywords: Diesel 50ppm, diesel 2000ppm,emissions SO2

1. Introduction Sulfur and its oxides are included in the refinery products specifications , for instance diesel and gasoline. On this regard, and despite the limited access to new sources of conventional oil, the refining sector faces challenges in relation to the growing demand for petroleum products ultraspecified (Bentley, 2002; Adelmam, 2004). Specifically in the case of Brazil, the use of diesel with a maximum of 50 ppm sulfur (S-50 diesel) should grow in proportion to the fleet adapted to use this fuel. Originally, the law established a mandatory distribution until 2009 (CONAMA, 2002; CONAMA, 2009; CasteloBranco et al. 2011), but this deadline was extended until January 2012 due to the major technological changes needed. 252


The emissions of SOx come from various factors, such as fires, industrial gases, decomposition of organic matter, among others. Fossil fuels burning contributes with 40% of air pollutants in urban centers (MMA, Ministry of Environment). In this context, The National Council of Environment (CONAMA) established in 1986 the Program for the Control of Air Pollution from Motor Vehicles (Proconve, 1986)29, with the participation of Brazilian refineries and car manufacturers, Petrobras (2009). Proconve aims at reducing sulfur content in fossil fuels and adapting diesel engines to use lower sulfur content fuel, as described in CONAMA Resolution 414, number 184 (MMA, 2009). In response to PROCONVE, diesel engines manufacturers and refineries were forced to improve theirs low sulfur diesel production and use technologies (McClellan et al., 2012). Environmental restrictions regarding emissions and fuel produced at the refinery are currently the most important issues in this matter, as well as more expensive to meet (U.S., 1995, U.S. EPA, 1999; ECC, 2001; ECC, 2003). In the context of reducing environmental and human health impacts, oil companies implemented new technologies to clean these products, namely by introducing hydrodesulfurization processes (HDT) and hydrocracking (HCC) in units of production of gasoline and diesel blends (Plantenga and Leliveld, 2003; Lu et al, 2006.;Jeyagowry et al. 2006).

However, units of ultra deep

hydrodesulphurization are generally high power consumption, increasing CO2 emissions (Babich and Moulijn, 2003). Several alternatives have been tested, in particular the conversion units and hydro treating / hydro cracking, together with the integration of refining petrochemicals (Williams, 2003; Martino and van Wechem, 2002). In this context, this study compares the environmental impacts associated with the changes associated with production and use of diesel 2000ppm and 50 sulfur content, specifically before and after the creation of PROCONVE, for two different regions, rural and urban areas of the State of São Paulo. The study is based on secondary data from a typical refinery, as defined in a commercially available LCI database, and statistical data from production and use of diesel in the State of São Paulo.

1.1 Objective and Scope

As mentioned in Proconve (Proconve, 1986), and since diesel represents 70% of total fossil fuels used in Brazil, diesel vehicles is a major cause of emissions linked to acid rain and soot in large urban centers, especially when

occurring thermal inversion phenomena, causing serious

respiratory problems in the population. In this scenario, and due to diesel consumption increase associated with higher environmental damage perception , it was prioritized the sulfur levels reduction in diesel fuel. On this regard, this study aims at comparing environmental impacts associated with the effects of production and consumption of diesel Brazil, before and after Proconve, specifically those related to potential soil acidification and human toxicity, beyond global warming potential - GWP. The

29

This program is derived from similar policies adopted in the European Union, namely the “Convention on the Long Range Transboundary Air Pollution” (CLRTAP) (1979). 253


analysis will encompass two spatial scales as well, the city of São Paulo and the countryside of São Paulo State. Prior to the implementation of PROCONVE, the country produced and used for its consumption the diesel with level of 2000 ppm, ie, 2000 parts per million of sulfur in the fuel.

2 Materials and Methods 2.1 System boundaries

In this paper, it is evaluated the emissions from production and use of diesel fuel S50 and S2000 in the areas of rural and urban regions of the State of São Paulo, considering the capital of São Paulo as the urban region and the rest of the State as rural. The study assumes that 50ppm diesel is distributed throughout the metropolitan region of São Paulo city30, while diesel S2000 use is confined within rural area(GaBi database only describes 2000ppm rather than 1800ppm). The consumption of diesel will be normalized by the area of the respective region of utilization. Besides, to characterize the scenarios presented in this study, it is assumed that diesel oil composition is completely fossil, although in 2004 the process of mixing of biodiesel in the diesel fossil in concentrations ranging from 2 % to 5% was initiated. These evaluations use LCA methodological approach to characterize the emissions associated with the three conditions for two periods of time, before and after the Proconve implementation, since Life Cycle Assessment (LCA) has been an important tool to assess potential impacts associated with the production and use of fossil fuels. Moreover, though LCA is a tool widely used in European countries and North America, in Brazil its use is still under development, and this study also contributes to expand its use in the Brazilian context.

2.2 Functional Unit

The functional unit was defined as the production and consumption of 1k of diesel, with 50ppm and 2000ppm of sulfur content, depending on the specific scenario. . 2.3 Sources of Data

The cradle to gate inventory of this study includes secondary data for two life cycle phase. The first phase is the production of diesel in two refinery, as reported at GaBi4.4 database, specifically for 50 and 2000 ppm fuel production. The second phase, the fuel consumption, was based on government data of metropolitan and rural areas of the State of São Paulo (IBGE, 2012). Both total and region specific diesel production and consumption data was acquired on crude oil Brazilian agency (ANP, 2013). The use of fossil fuel was simulated in Gabi6 software for a Euro III truck (load capacity of 9.3 tonnes, database EP, 2013), representing the average Brazilian fleet truck.

3 Diesel in the State of São Paulo According to the Supply Sector of the ANP (2013), all diesel distributed must be considered as consumed, called the apparent consumption. Therefore, the information used is based on data 30

The metropolitan areas were responsible for 58.53% of São Paulo State population in 2010, according to Pasternak (2010). 254


reported by the companies responsible for distribution. According to ANP (2012) in 2006, before Proconve , diesel consumption in the State of São Paulo was of 9,205,030 m3, while in São Paulo city, this figure was of 1,282,272 m3, according to data from the Municipal Secretary of Energy (ARSESP 2011). Although São Paulo city has quite an heterogeneous distribution of 50ppm diesel, as far this study is concerned,

it is assumed that in 2011 the State capital consumes only this

low sulfur

3

concentration fuel, specifically 1,706,649 m (ARSESP,2011). It is also assumed that in 2011 all the cities of the State, except its capital, consume diesel with 2000ppm sulfur, specifically 10,195,522 m3 (ARSESP, 2011). Moreover, in the context of this study, it is assumed that the region considered as rural includes the whole State of São Paulo, except the metropolitan region of São Paulo city. On the other hand, it is assumed that the region understood as urban limited only to the metropolitan capital of São Paulo.

4 Results Figure 1 depicts the information flow of the data to achieve the figures presented at Table 2 and 3. SO2 and CO2-equivalent are calculated in GaBi6.0 software, using the datasets aforementioned, for all the spatial and temporal scenarios defined. These emissions figures are combined with diesel consumption data, and the total emissions are afterward normalized by the respective areas.

Figure 1 – Calculation information flow Table 1 shows the total consumption of diesel distributed over two defined regions. The figures depict that while the total diesel consumption increases of 29,03% between the two years, the consumption of diesel in the capital augments 33,1% and in the countryside of 28,69%. Table 2 describes the emissions of SO2 in the two scenarios analyzed, in function of the two spatial scales and two concentrations of sulfur in diesel. Similarly, Table 3 describes the emissions of CO 2 in the two scenarios analyzed, in function of the two spatial scales and two concentrations of sulfur in diesel. In both tables, it is adopted the normalization of the total emissions generated by the area of the respective geographic region. Moreover, it is also presented the variation of emissions between the two years. On this regard, the tones/km2 normalized figure that describes only the variation associated with the total amount of diesel consumed per area is the CO 2-eq/km2 emission in the use phase, namely an increase of diesel consumption in the São Paulo capital and country-side of, respectively, 133% and 129%. All the others variation combines the variation of diesel consumed altogether with the effect of the implementation of the technology to produce Diesel 50ppm. 255


The normalized CO2-eq emitted at the production phase in the capital and country-side of, respectively, 199% and 129%. As far as the SO2 emissions per area are concerned, during the production phase is presented an increase of 193% and 129%, respectively, in the capital and countryside. Moreover, during the use phase is obtained an increaseof 3,33% in the capital, and an increase of 129% in the countryside.

Table 1 - Total Consumption of Diesel, Distributed by Regions 2006

2011

Variation %

Total Diesel SP State Consumption

9.205.030,00

11.902.171,72

29,00

Countryside Consumption (kg)

7.922.758,00

10.195.522,37

28,69

(86,07%)

(85,66%)

1.282.272,00

1.706.649,35

(13,93%)

(14,34%)

Capital Consumption (kg)

33,10

Table 2 - Comparison of Temporal Scenarios for Emissions of SO2 (total figures in tones and normalized in t/km2; percent values represent variation between the two years) Timescale Scenari

Spatial

os

Scale

SP - State capital 1

2006 Producti on S2000

2011 Use S2000

1,292t

4,359t

0.850t/k

2.866

m

t/km2

SP – State

7,987t

26,937t

countrysid

0.032

0.109

2

t/km2

e

SP - State capital 2 SP - State countrysid e

2

t/km

Production S50

Productio Use S50 n

Use S2000

S2000

2,498t

145t

1,642

0,095

2

t/km

t/km2

193%

3.33% 10,278t

34,664t

0,042

0,141

2

t/km

t/km2

129%

129%

Regarding the objective of this study, these results present that due to the implementation of Proconve program there was a decrease of the total and normalized SO2 emissions in the capital of São Paulo. Conversely, the emissions at production rose due to introduction of new processes necessaries for removing sulfur in the refining process. As the diesel consumed in countryside was not changed, its increase is only associated with the variation in the total amount of diesel consumed in that region. 256


Table 3 - Comparison of Temporal Scenarios for Emissions of CO2 (total figures in tones and normalized in t/km2; percent values represent variation between the two years)

Timescal e Sce

Spatia

nari

l

os

Scale SP

-

State

SP State

country side SP

Use

S2000

S2000

285,317t

3,477,629t

187,576

2,286,260

t/km –

2011

Production

2

capital 1

2006

1,762,889t 7,146 t/km2

Use S50

n S2000

Use S2000

21,487,187 t 87,098 t/km2

-

capital

SP

S50

Productio

t/km2

State

2

Production

568,305t

4,628,576t

373,615

3,042,914

2

t/km

t/km2

199%

133%

-

State country side

2,268,60

27,651,1

0t

16t

9,196

112,083

2

t/km

t/km2

129%

129%

5 Conclusions This study aimed at evaluating the change in emissions of sulfur oxides associated with diesel production and use in Brazil, due to the implementation of the Brazilian public policy Proconve. Thus, it was evaluated SO2 total emissions in two distinct regions of the State of São Paulo. The city of São Paulo was considered as the urban area and the countryside of the State the rural. From the consumption of each region it was evaluated emissions compared to diesel S2000, since its use was removed from urban area and totally replaced by diesel S50. It was found that in the rural area the emissions increased, but this increase was due to increase of the diesel consumption. Regarding the evaluation in the urban area, there was an increase of emissions of only 3,33% in the use due to insertion of the diesel S-50, despite the increase of 133% of diesel consumed in the capital of the State. These results demonstrate the success of implementation of Proconve, and of the use of new technologies for removal of sulfur from diesel fuel produced in Brazil, in the reduction of emissions of sulfur oxides in urban areas. 257


References Adelman M.A., 2004. The real oil problem.Regulation, 27(1):16–21. Agência Nacional do Petróleo (ANP) . Fonte: Distribuidoras de combustíveis autorizadas pela ANP, conforme Portaria ANP 202/99. ARSESP(Secretaria Municipal de Energia) 2011.http://www.energia.sp.gov.br/portal.php/dadosestatisticos, acesso em 15/11/2012 Babich, I.V., Moulijn, J.A., 2003. Science and technology of novel process for deep desulfurization of oil refinery streams: a review. Fuel, 82, 607-631. Bentley R.W., 2002. Global oil & gas depletion: an overview. Energy Policy, 30(3):189–205. Braglia, M., Bevilacquq, M., 2002.Environmental efficiency analysis for ENI oil refineries.Journal of Cleaner Production, 10, 85-92. CLRTAP.1979 Convention on Long-range Transboundary Air Pollution. Conselho Nacional de Meio Ambiente (CONAMA). Resolucao 315. Brasilia, novembro de 2002. Conselho Nacional de Meio Ambiente (CONAMA). Resolucao 414. Brasilia, setembro de 2009. Conselho Nacional de Meio Ambiente (CONAMA). Resolucao 414. Brasilia, novembro de 2009. Jeyagowry T, Xiao H, Dou J, Nah T, Rong X, Kwan W., 2006 A novel oxidative desulfurization process to remove refractory súlfur compounds from diesel fuel. Applied Catalysis B: Environmental, 63, 85–93. Lu¨ H, Gao J, Jiang Z, Jing F, Yang Y, Wang G, et al., 2006. Ultra-deep desulfurization of diesel by selective oxidation with [C18H37N(CH3)3]4[H2NaPW10O36] catalyst assembled in emulsion droplets. Journal of Catalysis, 75, 239 -369. Martino, G.,van Wechem, H.,2002. Current status and future developments in catalytic technologies related to refining and petro chemistry. Petrole et Techniques 440,47-65. McClellan, R. O., Hesterberg, T.W., Wall, J.C., 2012. Evaluation of carcinogenic hazard of diesel engine exhaust needs to consider revolutionary changes in diesel technology. Regulatory Toxicology and Pharmacology, 63, 225-258. Ministry of Science and Technology (MCT), Brazil; 2009. Brazilian inventory of anthropogenic emissions and removals of greenhouse gases. Ministry of the Mines and Energy (MME), Brazil, 2007.Brazilian Energy Plan 2030 (InPortuguese).Brazilian Government Enterprise for Energy Planning (EPE).Rio de Janeiro. .Acesse in 16 july 2012. Pasternak S., 2010. O Estado de São Paulo no Censo 2010. Instituto Nacional de Ciência e Tecnologia. http://www.observatoriodasmetropoles.net/, acesso em 18/11/2012

258


Plantenga F, Leliveld R., 2003. Sulfur in Fuels: more stringent sulfur specifications for fuels are driving innovation. Applied Catalysis A:General, 248, 1–7. Williams, B., 2003. Future energy supply-5: refining adjustments. Oil and Gas Journal 101 (32), 20–34.

259


LCA Case Studies

260


Environmental Study of the Sugar and Bioethanol Industry based on Sugarcane by using a Life-Cycle Assessment Approach. A Case Study in the Northwestof Argentina Nishihara Hun, Andrea L.*– Mele, Fernando D. – Hernández, María Rosa Dep. Ing. de Procesos y Gestión Industrial – FACET –Universidad Nacional de Tucumán, Av. Independencia 1800, San Miguel de Tucumán, Argentina

* +54 381 410 7573, [email protected]

Abstract This paper presents a study of the environmental impact of the production of sugar and bioethanol according to the common practices in the Northwestern Argentina (NOA) region, using the technique of Life-Cycle Analysis (LCA). Keywords Sugar and ethanol industry, Environmental impact, Vinasses

1 Introduction Energy production is vital for economic development and poverty reduction. Nonetheless, it is common knowledge that the unavoidable depletion of non-renewable energy sources on the planet and the pollution caused by the use of these sources lead to urgently redefine concepts and develop sustainable energy policies. Nowadays, fossil fuels coverjust over 90% of the global energyneeds, with oil as the leader source. Being transport the human activity with the biggest energy consumption, this sector has now reached such an activity volume that the generated environmental problems are more and more important: almost total dependence on oil, low energy efficiency and high production of greenhouse gases (GHG). The introduction of biofuels in the transport sector is one of the measures proposed to mitigate this problem. They are a source of domestic energy, technically feasible, which has the potential to substantially reduce CO2 emissions (Lechónet al., 2007). Many countries have implemented policies to regulate the biofuels production and Argentina is not an exception. In 2006, Law 26093 –for regulation and promotion of the biofuels production and use– has been approved, initially being required a share of 5% bioethanol and biodiesel to gasoline and diesel, respectively, from the year 2010. With this, the sugar-alcohol industry was faced with the challenge of producing high quality products to meet consumer demand. However, Argentine farmers need to study the environmental performance of its products to meet sustainability criteria. (Farrell et al. 2006). Argentina as a producer of ethanol from sugarcane couldnotbe environmentallycompetitiveunlessspecific measuresare implemented. These measures have to do with avoiding deforestation, implementing sustainable farming techniques, using lowtoxicity pesticides and improving technologies to reduce and treat large volumes of the wastewater (vinasses) generated. The purpose of this paper is to provide a starting point for quantifying loads and environmental impacts of the sugar-ethanol industry from sugar cane in Argentina using the LCA as a tool. Thus, it will be possible to identify those lifecycle activities that cause major impacts. In addition, there will be some guidelines to improve the industry from the environmental point of view.

2 Background In spite of the potential benefits of bioethanol derived from sugarcane, there are some drawbacks 261


associated with this biofuel, such as competition with food for land, the impact associated with the transport sector in agricultural and logistics tasks, and generation of large amounts of stillage during the process. In particular, one of the key issues that has not been considered so far is the assessment of the environmental impact of the ethanol production in Argentina from the perspective of LCA, as has been done in the case of Argentine production of biodiesel. Examples ofapplicationsto the case of the Argentinesoybeanbiodieselarethe worksbyAsalet al. (2006), Panichelliet al. (2009), and Tomei and Upham (2009). Withregardto LCAapplied tosugarcaneethanol, somerelevant contributionsin the literatureare relatedto production inother countries, for instance Australia (Renoufet al. 2011), Brazil (Omettoet al. 2009) –from where most of the works come- and Colombia (Sánchez et al., 2007). There are several reasonsto evaluatesugarcaneethanolin Argentinafrom the LCA point ofview: (i) Thisfuelis based onrenewableresources, in contrast to othertypes of fuels; (ii) sugarcaneoriginatesone ofthe main economic activitiesin rural areasofNOA, with manyenvironmental and socialimplications; (iii) aspecificlocal approachiscrucialin the LCA-based evaluationof bioenergy systems: local conditions, such as agricultural practises, change in land use and transport infrastructure will have a significant impact on the environmental performance of the system; (iv) Manystagesof the life cycleof ethanolin Argentinahave remained unchangedfor a long timeso thepotential improvementis imminent; (v) Argentine ethanol producers need to assess the environmental performance of its products to meet the requirements on sustainability issues. The next stepin a LCA study isits extension totheconsideration of uncertainty(sensitivity analysis), and the use of the resultsintoan optimization problem(multiobjective) whichconsider economic and environmentalcriteriaat the sametime. Asa contribution in thislastline isa work ofthe authors (Meleet al., 2011). Other LCA applications on the sugarcane-based industry are the works by Arvidssonet al.(2012), Contreraset al. (2008), Wilosoet al. (2012), Kiatkittiponget al. (2009) and GrilloRenóet al.(2011).

3 Methodology Data used in this paper come from an industrial complex of NW Argentina (NOA). It comprises a plant that manufactures sugar (mill) coupled to a plant that produces ethanol (distillery). As time boundaries, a harvest year was considered (zafra), from May to November 2010. To define the spatial boundaries of the system, the approach "form cradle to gate" has been used, that is from raw material –sugarcane– cultivation until the production of sugar and bioethanol as finished products. The whole system has been divided into three subsystems: Agriculture, Mill and Distillery. In the subsystem Agriculture, sugarcane is planted, treated with fertilizers and biocides, harvested and transported to the sugar mill. In the subsystem Mill, sugar is obtained as a product whereas bagasse, filter muds and molasses are generated as by-products. Bagasse is the milling lignocellulosic residue of the sugarcane, which is burned in boilers to generate power in the plant itself, and it is not a net outflow. The filter muds are sludges resulting from the purification step of the juice, which are recycled to the subsystem Agriculture. Molasses are the final honeys with high content of non-crystallizable sugars, which are sent to the distillery. In the subsystem Distillery, the molasses, through fermentation, distillation, and other processes, becomes alcohol 96 % vol. firstly, and then, absolute (anhydrous) alcohol with a purity higher than 98 % vol. Moreover, vinasses, the main liquid effluent from the distillery, are considered to be destined to field fertirrigation. As a functional unit a mass flow has been taken: 100 t of harvested sugarcane, which is sugarcane ready for entry to the mill. Inputs and outputs of each subsystem have been identified and quantified (LCA inventory phase). 90% of the data has been provided by the company. The remaining 10%, such as some emissions to air, water and soil whose information was not available, has been obtained from literature. Mass allocation has been used as allocation method. The LCA study has been done with the aid of the program SimaPro ® using as an impact assessment (impact assessment phase of LCA) the Eco-Indicator 99.

4. Case Study and Results Tables 1, 2 and 3 show the main input and output data considered in this case study for the three 262


subsystems: Agriculture, Mill and Distillery. Table 1. Subsystem Agriculture. Referred to 100 t of sugarcane. Inputs Amount Outputs Amount Outputs land use 0,856 ha sugarcane 100 t Emissions from harvest burning Solmix 281 L O2 26,72 t CH4 diammonium 321 L Emissions to the air N2O phosphate TCA 3,25 kg N2O nitrification 14,55 kg NOx Dalapon 2,44 g NOx 24,31 kg SOx Ametrina 1,71 L NH3volatilization 3,852 kg NMVOC Atrazina 1,71 L Emissions to the Emissions from diesel water combustion Decis 0,073 L NO3lixiviation 40,061 CO kg Diesel 16,2 L phosphate 2,054 kg NOx filter muds 6,31 t pesticides 32,357 g SO2 CO2 36,13 t particles

Table 2. Subsystem Mill. Referred to 100 t of sugarcane. Inputs Amount Outputs sugarcane 100 t white sugar natural gas 22,58 m3 raw sugar water 610 m3 molasses bactericides 894,3 kg filter muds sodium hypochlorite 73,9 g Emissions to the air NaCl 1502,3 kg CH4 lime 104,03 kg N 2O sulphur 24,08 kg NOx H3PO4 0,92 kg SOx NaOH 8,19 kg VOC HCl 248 g particles Emissions to the water DBO5 suspendedmaterial

Table 3.Subsystem Distillery. Referred to 100 t of sugarcane. Inputs Amount Outputs molasses 3,87 t alcohol96 % naturalgas 101,97 m3 low grade alcohol Water 162,2 m3 alcohol redistilled sulphuric acid 33 kg absolute alcohol cyclohexane 2,23 kg fusel urea 0,447 kg vinasses phosphate 0,298 kg Emissions to the air CO2 Emissions to the soil sulphates total solids ammonia sulphides potassium

Amount

2,482 kg 0,171 kg 9,074 kg 1,113 kg 5,564 kg

2,754 kg 4,82 kg 0,551 kg 67 mg

Amount 9,995 t 0,967 t 3,87 t 6,31 t 1914 g 847 g 16,4 kg 6,8 kg 18,7 g 9,1 kg 13,2 g 19,8 g

Amount 1388,49 L 35,43 L 41,96 L 886,15 L 0,74 L 11,518 L

2,48 t

82,28 kg 866,42 kg 183,29 g 16,67 g 262,65 kg 263


The LCA inventory results usually contain hundreds of different emissions and resource extraction parameters. These parameters have to be then assigned to different impact categories by means of factors that reflect the relative contribution of an inventory value to an impact category. This paper uses the Eco-indicator 99 to cover the next stages of the LCA study. The Eco-indicator 99 defines the environmental impact in terms of three types of damages: - To the human health, that includes the following effects: climate change, stratospheric ozone layer depletion, carcinogenic and respiratory effects and ionizing radiation. - To the environment quality, that includes ecotoxicity, acidification, eutrophication and land use. - To the resources, that includes mineral depletion and fossil fuels depletion. Below are two figures resulting from the impact assessment and interpretation phases using the Eco-indicator 99. In both figures, the abscissa axis contains the 11 impact categories of the Ecoindicator 99, while the ordinate axis represents the impact measured through ecopoint values. Figure 1 shows the environmental impacts resulting from the subsystem Agriculture. It is worth noting that, as expected, from the point of view of climate change, the system has an environmental impact "positive", due to the consumption of carbon dioxide during the sugarcane growth.

Figure 1. Environmental impacts in the subsystem Agriculture. Figure 2 shows the environmental impacts of the global system whose main product is ethanol 96 % vol. Even less obviously, it arises from this figure, for example, that the distillery runs virtually the same amount of fossil fuels that the subsystems Agriculture and Mill together, pointing out a clear need for improvements. It is also noteworthy the negative impact arising from the land use, in the subsystem Agriculture, and that of course is reflected in the global system.

264


Figure 2. Environmental impacts in the whole system.

6. Conclusions This paper presents a study of the environmental impact of the sugar-alcohol industry, typical of NOA region, using the LCA tool. This is an important contribution because until now the LCA studies on the complex sugar/bioethanol in Argentina have been incipient. One of the most promising applications of the results of this LCA study is the use of the information within a multiobjective optimization framework on the sugar-alcohol industry.

References Ardvisson, R, Fransson, K, Fröling, M, Svanströn, M, Molander, S (2012) Energy use indicators in energy and life cycle assessments of biofuels: review and recommendations. Journal of Cleaner Production, 31, 54-61. Asal S, Marcus R, Hilbert JA (2006) Opportunities for and obstacles to sustainable biodiesel production in Argentina. Energy for Sustainable Development 10(2): 48-58. Contreras, A, Rosa, E, Pérez, M, Van Langenhove, H, Dewful, J (2008).Comparative life cycle assessment of four alternatives for using by-products of cane sugar production, Journal of Cleaner Production, 17, 772-779. Farrell AE, Plevin RJ, Turner BT, Jones AD, O‘Hare M, Kammen DM (2006) Ethanol can contribute to energy and environmental goals. Science 311(5781):506–508. Grillo Renó, ML, Silva Lora, EE, Escobar Palacio, JC, Venturini, OJ, Buchgeister, J, Almazan, O (2011) A LCA of metanol production from sugarcane bagasse, Energy, 36, 3716-3726. Kiatkittipong, W, Wongsuchoto, P, Pasavant, P (2009) Life cycle assessment of bagasse waste management options, Waste Management, Waste Management 29 (5), 1628-1633. Lechón, Y, Cabal, H, de la Rúa, C, Lago, C, Izquierdo, L, Sáez, R, San Miguel, M (2007) Análisis de ciclo de vida de combustibles alternativos para el transporte. CIEMAT. Ed. Centro de Pub. Secretaría Gral. Técnica, Ministerio de Medio Ambiente. ISBN: 84-8320-376-6. Mele FD, Kostin A, Guillén-Gosálbez G, Jiménez L (2011) Multiobjective Model for More SustainableFuel Supply Chains. A Case Study of the Sugarcane Industry in Argentina.Industrial & Engineering Chem. Res. 50, 4939–4958. Ometto AR, Hauschild MZ, Roma, WNL (2009) Lifecycle assessment of fuel ethanol from sugarcane inBrazil. Int J Life Cycle Assess 14:236–247. Panichelli L, Dauriat A, Gnansounou E (2009) Life cycle assessment of soybean-based biodiesel inArgentina for export. Int J Life Cycle Assess.14:144–159. Renouf MA, Pagan RJ, Wegener MK (2011) Life cycle assessment of Australian sugarcane products witha focus on cane processing. Int J Life Cycle Assess 16:125–137. Sánchez, O, Cardona, C, Sánchez, D (2007) Análisis de ciclo de vida y su aplicación a la producción de bioetanol: una aproximación cualitativa, Revista Universidad EAFIT, 43 (146), 59265


79. Tomei J, Upham P (2009) Argentinean soy-based biodiesel: An introduction to production and impacts. Energy Policy 37: 3890–3898. Wiloso, E, Heijungs, R, de Snoo, G (2012) LCA of second generation bioethanol: A review and some issues to be resolved for good LCA practice. Renewable and sustainable Energy Reviews, 16, 5295-5308.

266


Nitrous Oxide Emissions from Agricultural Soils: Effects on the Environmental Profile of Soybean Biodiesel Roxana Piastrellini* - Alejandro P. Arena - Bárbara M. Civit * Grupo CLIOPE Universidad Tecnológica Nacional Facultad Regional Mendoza, Cnel. Rodríguez 273, 5500, Mendoza, Argentina

++54 261 5243001 [email protected]

Abstract Purpose. Nitrous oxide (N2O) emissions from agricultural soils are the greatest source of greenhouse gas emissions associated with bioenergy crop production. At present, the most widely accepted methodology to estimate these emissions in biofuel life cycle studies is that proposed by the Intergovernmental Panel on Climate Change (IPCC); however, the emission factors used have large uncertainty ranges. In Argentina‘s Pampas region, field measurements suggest that this methodology may overestimate N2O emissions. The European Commission‘s Joint Research Centre (JRC) suggests the adoption of the model developed by Stehfest and Bouwman (2006) to obtain an approximation of the real values of emission. The purpose of this study is to analyze the influence of N2O emissions on the environmental profile of soybean biodiesel produced in Argentina. A sensitivity analysis was carried out to evaluate to what extent variations of N2O emissions originating from agricultural soils affect the results. Methodology. N2O emissions were estimated following the methodology suggested in the IPCC Guidelines (2006), including the evaluation of default emission factors and both ends of the uncertainty range. In addition, the JRC method was applied, bringing to bear edaphoclimatic and crop conditions. The case study focuses on the Argentine region of the Pampas. The functional unit defined is 1 MJ of energy obtained from soybean biodiesel. The impact assessment stage of the life cycle contemplates the categories included in the EDIP method (2003). Results. A significant influence of N2O emissions is observed on the environmental profile of soybean biodiesel, with variations in the results of 35% in the Global warming category, 8% in Ozone formation and 5% in Acidification and Eutrophication. The results obtained with the JRC methodology are considerably higher than the field measurements reported in the literature and the values estimated with the IPCC method. Conclusions. Among the methods studied, the JRC proposal seems to be the least favorable for application in soybean biodiesel production in Argentina.

Keywords: nitrous oxide, agricultural soils, soybean biodiesel, environmental profile

267


Introduction Most global N2O emissions are generated by biological processes stimulated by nitrogen inputs to agricultural lands (IPCC, 2007). These emissions are the largest source of greenhouse gases associated with bioenergy crop production (Adler et al. 2007; Crutzen et al. 2008), and their great variability and dispersion complicates assessment (Lane and Lant, 2012). The methodology proposed by the Intergovernmental Panel on Climate Change (IPCC) is currently the most widely accepted for estimating N2O emissions from agricultural soils in biofuel life cycle studies (Cherubini et al. 2009). This methodology assumes a linear relationship between the income of nitrogen to the system and N2O emissions, further including crop residues, leaching and ammonia losses (IPCC 2007). In spite of their extensive use in national inventories, the coefficients used have extensive ranges of uncertainty, particularly direct N2O emission factors (+ / - 300%) (IPCC 2006). Studies carried out by Álvarez et al. (2011) in the Pampas region suggest that field measurements of N2O emissions are considerably lower than those estimated on the basis of IPCC proposals. The Joint Research Centre (JRC) of the European Commission suggests the adoption of the statistical model developed by Stehfest and Bouwman (2006) in combination with the 2006 IPCC model to get an approximation of the real values of emission. The method incorporates climate and soil parameters such as temperature, precipitation, crop type, nitrogen fertilization rate, soil carbon content, pH and soil texture (Koeble and Leip, 2010). The purpose of this study is to analyze the influence of N2O emissions on the environmental profile of soybean biodiesel produced in Argentina. A sensitivity analysis was carried out to evaluate to what extent the variation in N2O emissions originating from agricultural soils affects the results.

Methodology The N2O emissions were estimated in accordance with the 2006 IPCC Guidelines, evaluating the default emission factors proposed by the guidelines and both ends of the uncertainty range (EF1: 0.003-0.03; EF4: 0.002-0.05; EF5: 0.0005-0025). On the other hand, the JRC method was applied, considering parameters pertaining to a temperate continental climate and medium soil texture, with pH values ranging between 5.5 and 7.3, and with low contents of organic Carbon (1-3%). It is important to emphasize that the method proposed by the JRC uses the equations proposed by the IPCC to estimate indirect N2O emissions, including only leaching and runoff processes. The case study focused on Argentina‘s Pampas region, more specifically, on the south area of Buenos Aires and north area of Santa Fe. The analyzed system covers the farming tasks needed to obtain energy crops (sowing, fertilization, pesticide application, harvest), as well as the industrial processes involved in the grain drying stages, vegetable oil extraction and biodiesel obtainment. The agricultural stage includes soybean production under no-till planting conditions, with average fresh yield values of 2900 kg/ha and applications of monoammonium phosphate (11% nitrogen) as fertilizer (Donato et al. 2008). The industrial stage was assumed to include the technology of vegetable oil extraction by solvent and the technology of methyl-ester obtainment by alkaline 268


transesterification. Inventory data, corresponding to those of an international level industrial plant with incorporations of local characteristics, were extracted from Jungbluth et al. (2007) and Huerga et al. (2009). As for land use, the conditions studied include the occupation of the nonirrigated arable land and the ocupation of the industrial plant according to production capacity and service life. The functional unit defined is 1 MJ of energy obtained from soybean biodiesel. The biodiesel use phase was not taken into account. Attributional allocation is performed based on the mass values for the products obtained at the industrial stage (soybean meal and glycerin). The impact assessment stage of the life cycle contemplates the categories included in the EDIP 2003 method (Hauschild, M. and Potting, J. 2004).

Results and Discussion As expected, direct N2O emissions of soybean crops outweigh indirect emissions, regardless the factors and methods used (Table 1), representing at least 80% of the total N2O emissions. Volatilization losses represent values below 2% of total indirect N2O emissions (Figure 1). The N2O emissions estimated using the IPCC method decreased 0.7 times when using the lower end of the uncertainty range, and increased their value 2.0 times upon applying the upper end of the uncertainty range of the emission factors proposed in the guidelines. On the other hand, upon applying the JRC method, it is observed that the emissions increase 3.6-fold with respect to those obtained with the IPCC default values (Table 1). Koeble and Leip (2010) estimated annual N2O emissions of soybean crops in Argentina using the Stehfest and Bouwman - IPCC combined model and found values between 1.73 and 3.93 kg N2O/ha for the Pampas region, which coincides with the value obtained in the present study by means of the same method (3.3 kg N2O/ha). Table 2 shows a significant influence of N2O emissions on the environmental profile of soy biodiesel. The impact categories affected are global warming, acidification, terrestrial eutrophication, human toxicity (air), ozone formation and nitrogen water eutrophication, while the rest of the categories remain constant. Table 1: Direct and indirect emissions of N2O for a soybean farm in the Pampas region, Argentina, expressed in kg N2O/kg soybean.

Method IPCC-Default values1 IPCC-Upper end

2

IPCC–Lower end JRC4 1

3

Indirect N2O emissions

Direct N2O emissions

Volatilization

Leaching/Runoff

Total N2O emissions

2.42E-04

2.90E-07

5.45E-05

2.97E-04

7.27E-04

1.44E-06

1.82E-04

9.10E-04

7.30E-05

6.00E-08

3.60E-06

7.67E-05

1.30E-03

….

6.14E-05

1.36E-03

EF1: 0.01; EF4: 0.01; EF5: 0.0075. 0.0005. 4 EF5: 0.0075.

2

EF1: 0.03; EF4: 0.05; EF5: 0.025.

3

EF1: 0.003; EF4: 0.002; EF5:

269


100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0% IPCC-lower-end

IPCC-Default value

Direct emissions

IPCC-lower-end

Volatilization

JRC

Leaching/Runoff

Figure 1: Contribution of direct and indirect processes to total N2O emissions of soybean crops in Argentina, according to the different emission estimation methods studied. Table 2: Impact analysis of 1MJ of energy obtained from soybean biodiesel in Argentina

Global warming 100a

kg CO2 eq

IPCC lower end 1.6E-02

Ozone depletion

kg CFC11 eq

2.7E-09

2.7E-09

2.7E-09

2.7E-09

m2.ppm.h

1.4E-01

1.4E-01

1.4E-01

1.5E-01

person.ppm.h

9.5E-06

1.0E-05

9.6E-06

1.0E-05

Acidification

m2

1.1E-03

1.2E-03

1.1E-03

1.2E-03

Terrestrial eutrophication

m2

1.7E-03

1.8E-03

1.7E-03

1.9E-03

Aquatic eutrophication EP(N)

kg N

1.2E-05

1.2E-05

1.2E-05

1.2E-05

Aquatic eutrophication EP(P)

kg P

1.8E-06

1.8E-06

1.8E-06

1.8E-06

Human toxicity, air

m3

1.7E+02

1.7E+02

1.7E+02

1.7E+02

Human toxicity, water

m3

1.2E-01

1.2E-01

1.2E-01

1.2E-01

Human toxicity, soil

m3

1.7E-03

1.7E-03

1.7E-03

1.7E-03

Water ecotoxicity, chronic

m3

8.1E-01

8.1E-01

8.1E-01

8.1E-01

Water ecotoxicity, acute

m3

2.7E-01

2.7E-01

2.7E-01

2.7E-01

Soil ecotoxicity, chronic

m3

1.4E-01

1.4E-01

1.4E-01

1.4E-01

Hazardous waste

kg

7.3E-07

7.3E-07

7.3E-07

7.3E-07

Slags/ashes

kg

2.5E-06

2.5E-06

2.5E-06

2.5E-06

Bulk waste

kg

8.9E-04

8.9E-04

8.9E-04

8.9E-04

Radioactive waste

kg

3.0E-07

3.0E-07

3.0E-07

3.0E-07

Resources (all)

kg

2.1E-06

2.1E-06

2.1E-06

2.1E-06

Impact Categories

Ozone formation (Vegetation) Ozone formation (Human)

Units

IPCC upper end 2.3E-02

IPCC default value 1.8E-02

2.7E-02

JRC

The greater impact is obtained upon applying the JRC methodology, in spite of the incorporation of local environmental conditions in the calculation. The JRC mentions the incorporation of climatic and edaphic characteristics (Koeble, R., 2011) as one of the advantages of the proposed method. Nevertheless, field trials carried out in the province of Buenos Aires, Argentina, show that certain parameters such as pH and soil organic carbon are not statistically related with the nitrous oxide emissions of agricultural soils (Ciampitti, et al 2005). When the JRC methodology and the IPCC methodology are compared using default values, increments in the results reach 35% in the Global warming category, 8% in Ozone formation, 9% in 270


Terrestrial eutrophication, 5% in Aquatic eutrophication and Acidification, and 2% in Human toxicity (Figure 3). With regard to the assessment of the influence on the environmental profile when considering the ends of the uncertainty range in the IPCC factors, it appears that the variations are much more important when using the upper end of the range, resulting in increases of 31.1% for the Global warming category (Figure 2). By contrast, when using the lower end of the uncertainty range, the results decrease 10.9% for this impact category.

% 35,0

IPCC -upper end 31,1

30,0

IPCC - lower end IPCC -default value

25,0 20,0 15,0 10,0 5,1

5,0 0,0 -5,0 -10,0

-1,8

GW

OF (V)

5,7

4,9 -1,6

OF (H)

Ac

2,9

3,2

-1,1

-1,2

-2,0

Te

Ae (N)

1,2 -0,4

Hta

-10,9

-15,0

Figure 2: Percentual variation of the environmental impact of 1 MJ of energy of soybean biodiesel in Argentina, having applied the ends of the uncertainty range in the N2O emission factors proposed by IPCC. Impact categories: Global warming (GW); Ozone formationVegetation (OF-V); Ozone formation-Human (OF-H); Acidification (Ac); Terrestrial eutrophication (Te); Aquatic eutrophication-Nitrogen (Ae-N) and Human toxicity-air (Hta).

271


GW

Hta 97,9

Ae (N)

100 % 90 80 70 60 50 65 40 30 20 10 0

IPCC -default value

OF (V) 91,9

94,8

92,2

91

Te

OF (H)

95,1

Ac

Figure 3: Comparison of the environmental impact of 1 MJ of energy of soybean biodiesel in Argentina having applied the methodology of the JRC and the IPCC methodology (default values of the emission factors). Impact categories: Global warming (GW); Ozone formation-Vegetation (OF-V); Ozone formation-Human (OF-H); Acidification (Ac); Terrestrial eutrophication (Te); Aquatic eutrophication-Nitrogen (Ae-N) and Human toxicity-air (Hta).

Conclusions The environmental profile of soybean biodiesel in Argentina is largely influenced by the values adopted in the N2O emission factors, as well as by the emission estimation method implemented. The Global warming impact category presents important variations in the results (up to 35%), although this is not the only category that is affected. Applying the JRC methodology involves assigning an environmental burden greater than that of real situations, and even greater than that estimated when using the upper end of the uncertainty range of the IPCC method. Therefore, the JRC proposal seems to be the least favorable of the methods assessed for the study of soybean biodiesel production in Argentina.

References Adler, P., Stephen, R., Del Grosso, J. and Parton, W.J. 2007. ‗Life-Cycle Assessment of Net Greenhouse-Gas Flux for Bioenergy Cropping Systems.‘ Ecological Applications, 17(3), 675-691. Álvarez, C., Costantini, A., Alves, B., Jantalia, C., Alvarez, C., Urquiaga, S. 2011. Emisiones de óxido nitroso bajo diferentes secuencias de cultivo y sistemas de labranza en la región Semiárida PampeanaArgentina. Memorias del XXXIII Congresso Brasileiro de Cincia do Solo. Minas Gerais, Brasil Cherubini, F., Bird, ND., Cowie, A., Jungmeier, G., Schlamadinger, B., Woess-Gallasch, S. 2009. Energyand greenhouse gas-based LCA of biofuels and bioenergy systems: key issues, ranges and recommendations. Resources, Conservation and Recycling, 53 (8), 434-447. Ciampitti, I., Ciarlo, E., Conti, M. 2005. Emisiones de óxido nitroso en un cultivo de soja [Glycine max (L.) Merrill]: efecto de la inoculación y de la fertilización nitrogenada. CI. Suelo (Argentina), 23 (2), 123-131. Crutzen, P.J., Mosier, A.R., Smith, K.A. and Winiwarter W. 2008. ‗N2O Release from Agro-Biofuel Production Negates Global Warming Reduction by Replacing Fossil Fuels.‘ Atmospheric Chemistry and Physics. 8, 389-395. 272


Donato, L, Huerga, I, Hilbert, A. 2008. Balance energético de la producción de biodiesel a partir de aceite de soja en la republica argentina. INTA Reporte, N° Doc. IIR-BC-INF-08-08. Hauschild, M. and Potting, J. (eds.) 2004. Spatial differentiation in life cycle impact assessment: the EDIP 2003 methodology. Guidelines from the Danish Environmental Protection Agency, Copenhagen, pp. 285. Huerga, I., Hilbert, J.A., Donato, L. 2009. Balances energéticos de la producción argentina de biodiesel con datos locales de la etapa industrial. INTA Reporte, N° Doc IIR-BC-INF-03-09.

IPCC. 2006. Guidelines for National Greenhouse Gas Inventories, prepared by the National Greenhouse Gas Inventories Programme, Eggleston H.S., Buendia L., Miwa K., Ngara T. and Tanabe K. (eds). Published by: IGES, Japan. IPCC. 2007. Climate change 2007: the physical science basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge, UK Jungbluth, N., Faist Emmenegger, M., Dinkel, F., Stettler, O., Doka, G., Chudacoff, M., Dauriat, A., Gnansounou, E., Sutter, J., Spielmann, M., Kljun, N., Schleiss, K. 2007. Life cycle inventories of bioenergy. Data v2.0 (2007), ecoinvent report No. 17, Swiss Center for Life Cycle Inventories, Uster. Koeble, R., Leip, A. 2010. Global pattern of N2O emissions from soils due to cultivation of potential biofuel crops. EC DG Joint Research Centre. Draft version 0.2 (19.05.2010). Koeble, R. 2011. Quantification of N2O Emissions from Biofuel Feedstock Cultivation. EUROCLIMA Expert Consultation on Greenhouse Gas Emissions from Biofuels and Bioenergy. Buenos Aires, 29/30.03.2011 Lane, J. and Lant, P. 2012. ‗Including N2O in ozone depletion models for LCA.‘ Int J Life Cycle Assess. 17:252–257. Stehfest, E. and Bouwman, A. F. 2006. N2O and NO emissions from agricultural fields and soils under natural vegetation: summarizing available measurement data and modeling of global annual emissions. Nutr. Cycl. Agroecosyst. V74 (3): 207-228.

273


Urea formaldehyde resin: impacts on the productive life cycle of wood based panels DiogoAparecido Lopes Silvaa*, Agnes Narimatsua, Fabio Puglieria, Francisco Antonio Rocco Lahrb, Aldo Roberto Omettoa. a. Departmentof Production Engineering, São Carlos School of Engineering, University of São Paulo, Trabalhador Sao-carlenseavenue 400, São Carlos, 13566-590, Brazil b. Departmentof Structure Engineering, São Carlos School of Engineering, University of São Paulo, Trabalhador Sao-carlense avenue 400, São Carlos city, 13566-590, Brazil

* Corresponding author. Phone: +55 16 33738206 E-mail address: [email protected] (D. Silva)

Abstract This paper presents a discussion aboutkey potential environmental impacts of urea formaldehyde resin (UF) on the productive life cycle of wood based panels. In this sense, we applied the technique of Life Cycle Assessment (LCA) in accordance with ISO 14040 and 14044 standards, considering cradle to gate life cycle perspective of MDP (medium density particleboard) produced in Brazil. The data collection phase was based on primary data collected in a UF resin producer in the country,and also on secondary data from literature. For environmental impacts assessment, potential impacts have been quantified by CML (2001) method. The environmental impact categories selected were: abiotic depletion (AD), global warming (GW), acidification (AC), eutrophication (EP), photochemical ozone creation (POC), freshwater aquatic ecotoxicity (FAE) marine aquatic ecotoxicity (MAE), terrestricecotoxicity (TE) and human toxicity (HT).The results showed that the major environmental hotspots occurred due to methanol and urea production, which are raw materials on UF resin life cycle and due to air emissions of formaldehyde from MDP production. The results showed that major environmental impacts of UF resin varied from 2.5 to 43.3%, respectively, for MAE and POC categories. In order to improve the eco-efficiency of UF resin produced in Brazil, it was suggested to optimize urea and methanol resources consumption and also to reduce the molar ratio ofUF resin that was 25.0 to 30.0% higher than that produced in Europe. Finally, the paper presents subjects for future research Keywords: Life cycle assessment (LCA), Environmental impact assessment, Urea formaldehyde resin, Wood based panels, Medium density particleboard (MDP).

1- Introduction Wood based panels are classified as composite materials produced with processed wood (particles or fibers) and synthetic adhesive, in which the product thickness is considerably smaller than its width and length(Thoemen et al., 2010). Acomposite material has two constituent phases: one called matrix, which is continuous and surrounds the reinforcement phase. In the field of wood based panel production, reinforcing phase corresponds to the processed wood and matrix phase corresponds to adhesive. Biazus et al. (2010)emphasize the importance of reconstituted panels, where 73.0% of world production is concentrated in ten countries, with Brazil in 6 thplace.The particleboard/Medium Density Particleboard (MDP) is the most produced and consumed reconstituted panel around the world(Biazus et al. 2010; Thoemen et al. 2010). MDP is a particleboard built from agglutinated and compact particles fromreforested wood, which 274


are combined with heat and pressure application consolidating the product. It is produced in three layers, which the two surface layers consist of particles with smaller dimensions, and the inner layer, comprised of larger particles, being fundamentally applied on furniture sector (Silva, 2012). About the adhesives that can be applied on wooden panels, Maloney (1993) and Wilson (2009a)reported that the urea formaldehyde (FU) resin is the most common. For Iwakiri (2005), over than 90.0% of wood panels use this type of resin, in view of its low cost compared to others. The UF resin has polymeric origin and is thermoset (Iwakiri, 2005). Prepared via condensation process, the resin under heat action undergoes crosslinking internal (curing process). About environmental issues, Kinga et al. (1996)andAthanassiadou (2000)point out that air emissions of formaldehyde from healing process of UF resin is one of its main key problems.European Panel Federation (2004)defines free formaldehyde emissions as potentially carcinogenic.Athanassiadou (2000) cites that formaldehydein concentrations above 0.1 ppm in air can cause effects on human health, such as watery eyes, nausea and eyes, nose and throat irritation. Due to environmental appeal related to the free formaldehyde emissions, in Brazil, NBR 18410/2006-2 (ABNT, 2006) standard classifies the particleboard production (including MDP panel) regarding the content of free formaldehyde by the perforator method, as follows:  E1:low release of formaldehyde – less than orequal to 8 mg HOCH/100g of sample dried;  E2:medium release of formaldehyde – more than 8 and less or equal to 30 mg HOCH/100g of sample dried;  E3:high release of formaldehyde – more than 30 and less than or equal to 60 mg HOCH/100g of sample dried. According to Chipanski (2006), in Brazil, approximately 63.0% of particleboards marketed are classified as E2 and about 37.0% as E3 class. In order to better understand the environmental impact of UF resin applied as an input to produce wooden panels, this study discusses about the key impacts of UF resin on the productive lifecycle of the MDP panel for the Brazilian context.For this, it was adopted the Life Cycle Assessment (LCA)andsubsequently, the findings of the current study were compared with literature and propositions for improvement of environmental performance of the UF resin were formulated.

2- Methods 2.1 Definition of scope 2.1.1 Function unit

The functional unit provides a baseline which all input and output data are inventoried in a standard mathematical sense (ISO, 2006).In this case, as the function of UF resin studied is to be used as the matrix phase in the production of wooden based panel production, the functional unit was the production of 1m³ (or 630 kg) of MDP without coating production, and observing technical requirements from Brazilian codeNBR18410/2006-2. For each 1 m³ of MDP is necessary to consume 71.65 kgof UF resin, with 67.0% of solids content and molar ratio formaldehyde/urea of 1.35.

2.1.2 Description of system boundaries

It was visited one UF resin producer in Brazil located 500 km from São Paulo/SP, which currently holds about 50% of the Brazilian market of urea/formaldehyde. Dataset about MDP production for Brazilian conditions was taken from Silva (2012). The study was divided into two phases: production of UF resin and production of MDP, as outlined in the product system of Figure1.

275


RAW MATERIALS, WATER, FUELS & ELECTRICITY

PRODUCTION OF MDP

PRODUCTION OF UF RESIN

MANUFACTURING OF UF RESIN

EMISSIONS TO AIR, WATER & SOIL

FORESTRY PRODUCTION

RESOURCE ESTRACTION

UF RESIN USE

INDUSTRIAL PRODUCTION

Cradle to gate MDP panel life cycle

MDP PANEL (MEDIUM DENSITY PARTICLEBOARD)

Legend: Transport

Figure 1Product system defined  Production of UF resin: this phase involves two sub-phases: resource extraction and manufacturing of UF resin. In resource extractionwere considered: electricity, diesel (transportation of inputs), water, urea, methanol, formic acid and sodium hydroxide.We included on the system boundary the cradle to gate production ofurea (Ribeiro 2009), methanol (Camargo 2007), electricity (PE International, 2009a), diesel (SICV Brasil, 2009), formic acid (adapted de Sutter 2007) and sodium hydroxide (PE International, 2009b).In the manufacturing of UF resinsub-phase, the local emissions to air from production process were extracted from primary data of producer consulted; emissions to water and soil taken from Wilson (2009a).  Production of MDP:inventory data and the characteristics related to MDP production in Brazil were extracted from LCA study of Silva (2012) that considered the forestry and the industrial production sub-phases.The industrial production sub-phase involves UF resin application during the blending process. To analyze environmental impacts of UF resin consumptionemissions to air of free formaldehyde from UF resin using were grouped with impacts from resource extraction and manufacturing of UF resin sub-phases, both from production of UF resin phase.

2.3 Life cycle impact assessment (LCIA)

This phase aims at understanding and assessing the magnitude and significance of potential environmental impacts of a product system (ISO, 2006). Inventory data collected for the product system (Figure 1)were correlated with categories/indicators of environmental impactsby CML (2001) method (Guinée et al., 2001), following the three mandatory LCIA steps: selection, classification and characterization. For LCIA phase, GaBiEducation software 4.4 was used. The following categories were selected: acidification (AC), global warming (GW), abiotic depletion (AD), freshwater aquatic ecotoxicity (FAE), marine aquatic ecotoxicity (MAE), terrestricecotoxicity (TE) eutrophication (EP), photochemical ozone creation (POC) and human toxicity (HT).

3- Results Based on results from LCIA, environmental impacts are summarized in Table 1. The results include impacts of UF resin production phase and use of UF resin on industrial production of 276


MDPsub-phase. Table1Environmental impacts ofUF resin to produce 1m³of MDP Impact category Unit Result 2,53E-01 Acidification kg SO 2eq

Global warming Abiotic depletion Freshwater aquatic ecotoxicity Marine aquaticecotoxicity Terrestricecotoxicity Eutrophication Photochemical ozone creation Human toxicity

kg CO2eq kg Sbeq kg DCBeq kg DCBeq kg DCBeq kg PO-34eq kg C2H2eq kg DCBeq

2,54E-01 4,28E-02 2,70E+00 7,79E+01 6,38E-01 2,99E+02 6,40E-08 1,22E-01

Figure 2 shows relative contributions (%) of UF resin potential impacts in Table 1, related to production of MDP phase.

Figure 2 Relative environmental impacts (%)per impact category

Relative impacts - CML (2001)

Analyzing Figure 2, the relative impacts of UF resin as an input consumed on the productive life cycle of MDP was responsible for: 2.5% to MAE, 7.4% to HT, 10.6% to AC, 23.4% to GW, 23.8% to FAE, 25.4% to AD, 32.3% to EP, 33.7% to TE, and 43.3% to POC. Environmental impacts of UF resin were related primarily to raw materials production (cradle to gate) of urea and methanol toAC, GW, AD and EP categories. So, Figure 3 presents environmental impacts (%) of methanol and urea on UF resin production (considering resource extraction and manufacturing of UF resin sub-phases)for functional unit of 1 m³ of MDP. 100% 80% 60%

40% 20% 0% AD

Urea

AC

EP

FAE

GW

HT

MAE

POC

TE

Methanol

Figure 3 Relative environmental impacts (%) of methanol and urea per impact category 277


Figure 3 shows that over than 50.0% of impacts are related to urea and methanol for: AC, GW, EP and AD. For POC and toxicological categories, impacts were not much effective, less than 1.0% for MAE, FAE and TE categories. For all categories, impacts of urea were higher compared to methanol, except for GW. In Figure 3, hotspots for AC happened due to emissions to air of sulfur dioxide; for GWbecause emissions to air of carbon dioxide and methane; AD due to consumption of natural gas; and for EP because emissions to water of nitrogen and hydrocarbons. For categories POC, MAE, FAE, TE and TH, mostimportant impact has occurred in more than 50.0% mainly because of free formaldehyde emissions during UF resin application on the sub-phase of MDP industrial production. In Brazil, during industrial production of MDP, according to Silva (2012), there is a large consumption of heavy fuel oil, an energetic resource used in power plants, which was responsible for 59.2% of impacts to AC, 31.0% to AD and 27.1% to GW. Furthermore, Silva (2012) highlighted the application of glyphosate herbicide on forestry production sub-phase, being very relevant to categories of human toxicity and ecotoxicity. So, the influence of UF resin to these impact categories was reduced (see Figure 2) because the greater environmental relevance of heavy fuel oil and glyphosate on the cradle to gate MDP panel life cycle.

4- Discussion 4.1 Comparison with literature results

Wilson (2009a)inventoried life cycle (cradle to gate) of formaldehyde-based resins in wood composites industry from United States (US), including UF resin with formaldehyde/urea (F/U) molar ratio of 1.09,concluding that emissions to air of free formaldehyde and hydrocarbons are relevant for life cycle manufacturing inventory of UF resins. However, environmental impacts were not analyzed. About UF resin using in US, Wilson (2009b) reported air emissions data of free formaldehyde of 5.50E-2 kg/m³ of MDP produced. In the present work, the total amount of air emission of free formaldehyde inventoried was 1.45E01 kg/ m³ of MDP produced, being 90.0% (about 1.30E-01 kg/m³) from UF resin using on industrial production of MDP sub-phase. In this sense, local formaldehyde emissions during MDP industrial production were 57.7% higher than that inventoried by Wilson (2009b), agreeing with findings of Chipanski (2006), whoessentially classified Brazilian UF resins as E2 and E3, with medium and high release rate of free formaldehyde, respectively. Athanassiadou (2000)explains that the high rate of emission of formaldehyde depends directly on F/U ratio, and in Europe the range is 1.02 to 1.08, which allows the production of resins classified as E1, very similar to that addressed by Wilson (2009a) of 1.09.In Brazil, F/U ratio is greater, for example, Silva (2012) considering 57.0% of the domestic MDP production, found an average F/U ratio of 1.35, the same ratio adopted in this research, which is 25-30 % higher than that cited byAthanassiadou (2000) to the European context. In literature, there is a lot of discussion regarding the environmental impacts of UF resin with focus on free formaldehyde air emissions aspointed out by Kinga et al. (1996), Athanassiadou (2000) andEuropean Panel Federation (2004), that considered the impacts to human health. However, in this work as shown in Figures 2 and 3, other relevant environmental impacts were discussed, such as those related to methanol and urea production. About toxicological impact categories according to Figure 2,impacts of UF resin ranged from 2.5 to 33.7%, highlighting 33.7% of impacts to TE and 23.8% to FAE, therefore, for ecotoxicity categories. But, in the literature commonly focus is given to human toxicity impacts, like previously introduced. Garcia and Freire (2011) assessing the life cycle of MDP panel production in Portugal, concluded that production of UF resin (cradle to gate approach) was the largest contributor to the impacts of most categories analyzed by CML (2001), accounting 38.0 to 59.0% of all impacts. In this study, influence of UF resin for all environmental impact categories varied from 2.5 to 43.3%, lower than that observed by Garcia and Freire (2011). It happened because the life cycle inventory dataset of MDP in Brazil was taken from Silva (2012), whohighlighted glyphosate herbicide and heavy fuel oil as relevant resources in terms of their potential impacts.Consumption of glyphosate and heavy fuel oil were not assumed by Garcia and Freire (2011), because are not commonly covered by the European context. Furthermore, Table 2 shows more technological 278


differences between Garcia and Freire (2011) and Silva (2012) approaches: Table 2Technological differences between Garcia and Freire (2011) and Silva (2012) LCA studies Description Garcia and Freire (2011) Silva (2012) Wood Considered wooden residue as raw Considered only virgin wood from consumption material instead of virgin wood. forestry production. Energy Considered electricity generated by Electricity is consumed from Brazilian consumption cogeneration process. power grid mix, without cogeneration. Considered Eucalyptus species,which Forest species Considered Pinus species requires more fertilizers and herbicides adoption cultivation. consumption than Pinus. Therefore, all these technological differences contributed to change range of influence of environmental impacts of UF resin as input on life cycle of Brazilian MDP panel produced.

5- Conclusions This paper presented a discussion about the key potential environmental impacts of UF resin on the productive lifecycle of the MDP panel in Brazilby CML (2001) method. The results showed a range of 2.5 to 43.3% of relative impacts to UF resin. The environmental impacts of UF resin for AC, GW, AD and EP were linked to the raw materials methanol and urea. For POC, MAE, FAE, ET and HT categories, the hotspots happened due to emissions of free formaldehyde during usingUF resin on industrial panel production. Comparing the influence of UF resin applied in MDP production in Brazil with others countries cases it was found the existence of technological differences, which directly affect the influence level of UF resin in terms of its life cycle potential impacts. As example, between Brazil and Portugal, it was found that the impact of UF resin in Brazil varies from 2.5 to 43.3% and in Portugal ranged from 38.8 to 59.9% of all impacts on the productive life cycle of MDP panel. As suggestions, we emphasized the need to improve the eco-efficiency of urea and methanol production and/orto reduce the consumption of them in the production of UF resin. Furthermore, to minimize emissions to air of free formaldehyde should be focused on decreasing the F/U ratio of the resin, since the F/U ratio adopted in Brazil showed to be 25-30% higher than those in European countries. As future work, it is suggested to conduct LCA studies applied for other types of wood panels in whichUF resin is used. Also, focus on environmental comparison of UF resins with other alternatives is an interesting research topic, searching for more environmentally suitable resin alternatives.Finally, it could be compared the results of this research using more LCIA methods in view of to verify the influence of such methods on the hotspots identified, and especially for assessing toxicological impacts categories. Acknowledgements: The authors are grateful for the financial support provided by The Coordination for Graduate Personnel Improvement (CAPES).

References ABNT (2006) NBR 14810: Chapas de madeira aglomerada. Associação Brasileira de Normas Técnicas, Rio de Janeiro. Athanassiadou E (2000) Formaldehyde free aminoplastic bonded composites. Proceedings of 5th International Conference Environmental Pollution. p 15 Biazus A, Barros da Hora A, Gomes Pereira Leite B (2010) Panorama de mercado: painéis de madeira. BNDS Setorial. 32:49–90. 279


Camargo AM (2007) Inventário do ciclo de vida do metanol para as condições brasileiras. Dissertation, University of São Paulo. Chipanski E do R (2006) Proposição para melhoria do desempenho ambiental da indústria de aglomerado no Brasil. Dissertation, Federal University of Paraná. European Panel Federation (2004) Reclassification of formaldehyde by the International Agency for Research on Cancer (IARC) - a statement by the wood panels industry concerning workplace exposure. http://www.europanels.org/main_tc.html. Accessed 26 October 2012. Garcia, RP, Freire, FMCS (2011) Modelação Energética e Ambiental do Ciclo de Vida de Painéis Aglomerados de Partículas. Construlink 9:22–30. Guinée, J B (2001) Life cycle assessment: an operational guide to the ISO standards. LCA in perspective – operational annex to guide. Centre for Environmental Science, Netherlands. ISO (2006) ISO 14044: Environmental management–Lifecycle assessment–requirements and guidelines. International Organization for Standardization, Geneva. Iwakiri, S (2005) Painéis de madeira reconstituída. FUPEF, Curitiba. Kinga JD, Petrovici V, Zeleniuc O, et al. (1996) Distribution of formaldehyde emission in particleboards. Proceedings of the 8th WSEAS International Conference on System Science and Simulation in Engineering. pp 153–159 Maloney TM (1993) Modern particleboard and dry-process fiberboard manufacturing. Miller Freeman, San Francisco. PE International (2009a) GaBi software-system and databases for life cycle engineering. GaBi education database. BR: Power grid mix PE. Stuttgart, 2009. PE International (2009b). GaBi software-system and databases for life cycle engineering. GaBi education database. DE: Sodium hydroxide mix (50%) PE. Stuttgart, 2009. Ribeiro PH (2009) Contribuição ao banco de dados brasileiro para apoio à avaliação do ciclo de vida: fertilizantes nitrogenados. Thesis, University of São Paulo. SICV Brasil (2009) Metodologia padrão para elaboração de inventários de ciclo de vida da indústria brasileira – documento consolidado. Projeto Brasileiro de Inventários do Ciclo de Vida. Brasília: IBICIT/MCT. Silva, DAL (2012) Avaliação do ciclo de vida da produção do painel de madeira MDP no Brasil. Dissertation, University of São Paulo. 280


Sutter J (2007) Life cycle inventories of petrochemical solvents. Swiss Centre for Life Cycle Inventories, Zurich. Thoemen H, Irle M, Sernek M (2010) Wood-based panels - an introduction for specialists. Brunel University Press, London. Wilson JB (2009a) Life-cycle inventory of formaldehyde-based resins used in wood composites in terms of resources, emissions, energy and carbon, Wood Fiber Sci 42:125-143. Wilson JB (2009b) Life-cycle inventory of particleboard in terms of resources, emissions, energy and carbon. Wood Fiber Sci 42:90–106.

281


Carbon footprint of an integrated management system for restaurants and catering waste considering uncertainty Neus Escobar* - Neus Sanjuán *

Grupo ASPA. Departamento Tecnología de Alimentos, Edificio 3F, Universidad Politécnica de Valencia,

Camí de Vera s/n, 46022, Valencia, España

++34 963879366 [email protected] http://www.aspa.upv.es Javier Ribal Departamento Economía y Ciencias Sociales, Edificio 3P, Universidad Politécnica de Valencia, Camí de Vera s/n, 46022, Valencia, España Alfredo Rodrigo – Andrés Pascual Ainia Centro Tecnológico. Parque Tecnológico de Valencia. C/ Benjamin Franklin 5-11, 46980, Paterna (Valencia), España

Abstract Purpose: The goal of this study is to analyze the uncertainty in the carbon footprint of an alternative integrated waste management system. This system pretends to treat both Used Cooking Oil (UCO) and solid organic waste from restaurants and catering. UCO is valorized by biodiesel production and organic waste is treated by anaerobic digestion. Besides, a cogeneration system using the biogas from the anaerobic digestion is implemented in order to improve the sustainability of the process. Methods: An attributional LCA has been carried out following the ISO standards. The functional unit (FU) has been defined as the management of the amount of UCO and organic waste from restaurants and catering produced per person during a year, according Spanish statistics. Two alternative scenarios for the management of the FU have been studied: the alternative system proposed and a reference process. In the second, the organic waste is collected together with municipal solid waste; after sorting, the organic fraction is valorized by composting and the non-organic fraction which cannot be recycled is dumped in a sanitary landfill. After a sensitivity analysis for identifying the most influential parameters in the carbon footprint, the uncertainty analysis has been performed by using Monte Carlo simulation. Results and discussion: 282


GHG emissions are 106.6% lower in the proposed scenario. The alternative waste management system causes negative impact due to the avoided burdens of the electricity production from the CHP engine. The sub-stage contributing the most to the impact in the reference scenario is composting, whereas the electricity production has the greatest effect in the alternative scenario, producing carbon uptake. The most influential parameters in the carbon footprint are ―biogas production yield in AD‖ and ―electricity yield of the CHP engine‖, thus the uncertainty is more relevant in the proposed scenario but without compromising the overall results: the alternative scenario clearly outperforms the reference one. Conclusions: The carbon footprint is distinctly improved by the alternative waste management system proposed. However, in order to extend the use of LCA for decision making the uncertainty has to be accurately quantified, which implies gathering more information about key parameters. Recommendations: Further research work is needed in order to establish accurate probability distributions of the key parameters. The environmental performance should be broadened by studying other impact categories. An economical assessment would also help to decision making. Key words: waste management, used cooking oil, uncertainty, Monte Carlo simulation

1. Introduction The increasing awareness of the waste increase is a fact, not only in the European Union (EU) but worldwide. In consequence, the European Parliament and the Council recently approved the Directive 2008/98/EC with the aim to protect the environment and human health. Member states of the EU have to take measures to treat residues ranking prevention, reuse, recycling or recovery over disposal. The new Directive urges to establish the selective collection and sorting before 2015. Furthermore, the amount of biodegradable waste to be recovered from households, catering and food distribution has to reach 50% (in weight) of the total waste produced before 2020. Waste from restaurants and catering is basically made up of three types of residues: packaging, organic waste and used cooking oil (UCO). The treatment of organic waste consists mainly on composting or landfilling. According to Pascual et al. (2011), 421,142 tonnes of organic waste from restaurants and catering are produced per year in Spain. It is estimated that the production of UCO is about 80,000 tons per year (Rodrigo et al. 2011), being collected by authorized management companies. Since the EU Regulation 1774/2002 forbade using UCO for animal feed, biodiesel production has become the best alternative for its recovery. At the same time, the awareness of the energy demand and greenhouse gas (GHG) emissions from the transportation sector has increased, too. As a result, the Directive 2009/28/CE was approved to control the energy consumption in the EU and ensure the availability of transport fuels. It 283


establishes a 10 % target for energy from renewable sources in the motor fuel market of each Member State before 2020. The production of first-generation biofuels grew sharply in response to policies and targets like this around the world. However, there has been an intense debate over the sustainability of these biofuels, specially due to their competition with food and feed resources and also due to the indirect land use change (LUC) impacts. As a consequence, second-generation biofuels from waste biomass or from non-food feedstocks are gaining in importance. Carbon footprint (CFP) of biofuels has been extensively evaluated: whereas first-generation biofuels do not always cause a reduction of this impact, second generation biofuels do (Bai et al. 2010, Spatari et al. 2005, Wu et al. 2006). In this sense, biodiesel from UCO may cause even a greater improvement in the environmental performance, since it consists on a recovery of a waste and avoids its treatment. In fact, results from Hong Chua et al. (2010), Lechón et al (2006),Talens et al. (2010), Ou et al. (2009) confirm this decrease in GHG emissions. However, glycerin is produced as a byproduct during the oil transesterification, becoming a waste to be treated and disposed of safely if the demand for biofuels grows faster than the rate at which it is used by the pharmaceutical industry. No one of the mentioned studies about UCO considered the glycerin treatment or recovery. Arena et al. (2003), Beccali et al. (2001), Blengini (2008), Cadena et al. (2009), Güereca et al. (2006) studied the environmental impact caused by different waste management systems. Some of these studies suggested that the use of general data may increase the uncertainty of the results. Others performed a sensitivity analysis for determining the influence of some assumptions in the overall results, such as Bai et al. (2010), Halleux et al. (2008), Kim and Dale (2005) or Spatari et al. (2005). Some authors have used the Monte Carlo (MC) method to communicate the reliability of their results in municipal solid waste (MSW) treatments (Sonneman et al. 2003; Kaplan et al. 2004; Bao-guo et al. 2007) and in biofuel systems (Bernesson 2004; Malça and Freire 2010, 2011). The Integral-b project, funded by the LIFE programme, aims at developing an integrated triple function: to treat organic waste and UCO from the Spanish catering sector, to valorize the glycerin surplus, and to improve the sustainability and viability of the whole process. UCO is valorized by biodiesel production and the solid organic waste by anaerobic digestion. In addition, a cogeneration system is established, avoiding external thermal energy consumption and producing electricity. The Integral-b project has been developed by Ainia Technology Centre, FundaciónCidaut, Biogas Fuel Cell and Bionorte, all of them located in Spain. The goal of this study is to analyze how the uncertainty in some process parameters may influence the CFP of the system proposed by Integral-b as compared to a conventional management system for the same kind of waste. The study of the uncertainty is a prerequisite for a more thorough understanding of the environmental benefits and it is also an aid for decision making.

284


2. Methods An attributional LCA has been performed. The life cycle inventory (LCI) and life cycle impact assessment (LCIA) were carried out using the GaBi 4 Software and its databases (PE International 2006), and using also the Ecoinvent v2.1 database (Hischier et al. 2007). The MC simulation was performed by using the Analyst Tool of the GaBi 4 Software. 2.1 Functional unit

The functional unit (FU) has been defined as the management of the amount of UCO and organic waste from restaurants and catering produced per person during a year in Spain. The amount of UCO and organic waste was obtained from the literature sources mentioned in Section 1. Thus, based on Spanish population, the reference flow considered is 1.70 kgof UCO/inhabitant and year and 8.96 kg of organic waste/inhabitant and year. 2.2 System description

In order to quantify the improvement in the CFP generated by the Integral-b process, it has been compared to a reference scenario built with current waste management processes. Both scenarios, shown in Figures 1 and 2, are described below. It is assumed that the organic waste in the Scenario 0 is collected together with MSW, in a multicontainer system such as the one described by Iriarte et al. (2009). After sorting, the organic fraction is valorized by composting and the non-organic fraction which cannot be recycled is dumped in a sanitary landfill, generating avoided burdens due to electricity production by means of methane combustion. The collection of UCO takes place through a door-to-door container system, with the subsequent transport. Then UCO is delivered to the plant and biodiesel production starts based on a batch process, using methanol and a catalyst previously mixed. In the Integral-b scenario (Scenario 1) an integrated system is established. Biodiesel production is the same as described for Scenario 0, but using thermal energy from a CHP engine. The CHP engine uses biogas as a fuel together with the surplus of glycerin from biodiesel production, which is previously purified by using the flue gases from the CHP engine. The organic waste from restaurants and catering is collected as MSW in the same way as in Scenario 0 and then they are treated by anaerobic digestion, obtaining biogas for the CHP engine and digester sludge. After satisfying the CHP engine demand, the extra electricity is exported to the power grid, generating avoided burdens. Both Scenario 0 and 1 include the transport to a farm of the compost and the digester sludge, respectively. 2.3 Inventory data

The constitutive processes of both scenarios are not still operating jointly as integrated systems nowadays. Hence, primary and secondary data have been used to asses Scenario 1 and 2 and to make them entirely comparable. In this section, inventory data sources are described in order to explain input and outputs flows with regard to the FU. 285


In this case, the estimations for both scenarios are based on a biodiesel plant that processes 5,295 t/year of UCO. In the Scenario 1, the anaerobic digestion plant processes 20,000 t/year of organic waste and the CHP engine has a power capacity of 500-kW. In the Scenario 0, and according to the literature sources used, the MSW treatment plant has a processing capacity of 18,000 t/year of MSW generated in an urban locality with a density of 5,000 inhabitants/km 2. The Spanish grid mix from the GaBi professional database has been used. A standard Euro 3 truck has been used in road transport, as well as diesel supply in Europe (EU-15). The study estimates average collection distances, the same in both scenarios, of 100 km and 30 km for the UCO and the organic waste of the FU, respectively. The primary data of biodiesel production have been provided by the company Bionorte. Methanol and catalyst production processes have been obtained from the Ecoinvent v2.1 database. All the data involved in the anaerobic digestion have been provided by Ainia Technology Centre and Biogas Fuel Cell. Methane losses have been calculated according to Bachmaier and Gronauer (2007). The self-consumption rates of the anaerobic reactor are 5% in power and 10% in thermal energy from CHP. Data relating to the CHP engine have been provided by Cidaut. No CO2 emissions must be considered because they all arise from biogenic carbon. CH 4 emissions from the engine and the digester sludge storage have been calculated according to Bachmaier and Gronauer (2007). The solid fraction from the digester (Scenario 1) and the compost (Scenario 0) are assumed to be delivered to a farm located 25 km from the production plant. Data from Iriarte et al. (2009) have been used to determine the collection distance for the amount of MSW needed to manage the FU. The power needed for waste sorting has been obtained from Arena et al. (2003), as well as transportation distances of the waste. All inputs and gaseous emissions in the industrial composting system were gathered from Martínez-Blancoet al. (2010). The sanitary landfill for the non-organic fraction of MSW has been taken from Ecoinvent v2.1 database. 2.4 Sensitivity and uncertainty analysis

Much research work has been conducted to clarify the concepts linked with uncertainty and to conceive tools for its quantification (Huigbregts 1998a,b; Huijbregts et al. 2001; Ciroth et al. 2004; Von Bahr and Steen 2004). One limitation of life cycle methodologies is that all inputs and outputs are treated as deterministic values, when normally a large number of them are average values. The MC method allows converting the deterministic model into a probabilistic model where the result is not a single-value but a probability distribution of all the possible expected outputs. The uncertainty analysis has been performed by using this method in the GaBi 4 Analyst Tool. Previously a sensitivity analysis of a ± 20% change in all parameter was carried out for identifying the most influential ones. Those parameters that caused a variation of the CFP higher than 5% have been selected. The contribution to the uncertainty of the selected parameters has been assessed by means of 10,000 runs of the MC simulation. In each simulation run, each parameter can vary according to the previously fixed distribution function and a forecast distribution for the GWP is obtained between the 10th and 90th percentiles. The uncertainty distributions have been fixed following the criteria of the availability of 286


information. The GaBi 4 Analyst Tool only offers normal and equal distributions, the same type for all the parameters in each simulation. Equal distributions have been chosen in all cases, since the available information is restricted to a minimum and a maximum. Distance bounds have been fixed according to ordinary distances from cities to facilities in Spain. The bounds for technical parameters have been gathered from the Integral-b partners. In the case of technical parameters for MSW sorting and composting in Scenario 0, where no data were available, an arbitrary range of ±5% has been established. Bounds for methane content in biogas have been gathered from the study of Lastella et al. (2002) about the anaerobic digestion of semi-solid waste from the fruit and vegetable market in Italy. The key parameters chosen as well as their bounds are shown in Table 1.

3. Results The outcome of the MC simulation of both scenarios is represented in Figure 3 with box-andwhisker plots. The GaBi 4 Analyst Tool provides the results from MC simulation separated between inputs and outputs; in other words, two forecast distributions for each scenario are obtained, one for GWP accounting as an input and another one accounting as an output. Depending if the difference between emissions and withdrawals is positive or negative, the system will cause net GHG emissions or a net carbon uptake respectively. Electricity production from the Spanish grid mix uses non-renewable fossil resources. Hence, the avoided production of electricity entails avoided GHG emissions, translated into a carbon uptake in the LCIA. Therefore, Scenario 1 causes a negative impact due to the avoided burdens from electricity production, while Scenario 0 causes a positive impact although it also generates electricity from composting and MSW treatment (but less than Scenario 1). The Scenario 1 decreased the GWP around 106.6% (with regard to Scenario 0) in accordance with the mean values. In Scenario 1, the uncertainty due to parameters variation is more significant than in Scenario 0: whereas in Scenario 0 the coefficients of variation (CV) are 6.17% (output) and 4.19% (input), in Scenario 1 the CV are 10.40% (output) and 13.10% (input). However, the uncertainty in the CFP does not compromise the overall results and the Scenario 1 clearly outperforms Scenario 0. There is not any random scenario from the MC simulation where Scenario 0 produces less impact than Scenario 1. In Scenario 0 the uncertainty is more relevant in GWP as an output, since the contribution of the avoided GHG emissions to the overall impact is negligible (Figure 3), being mainly caused because of the electricity production from sanitary landfill in MSW treatment and composting. In Scenario 1 the greatest uncertainty is found for the GWP as an input, although it is also remarkable the uncertainty surrounding the output of GHG emissions. Figure 4 shows the sub-stages that contributed most to the GWP. For this analysis, collection transport includes the collection of UCO and organic waste from restaurants and catering, as explained in Section 2.3. In Scenario 1, anaerobic digestion also includes the solid-liquid separation and the transport of the solid fraction from the digester sludge to the farm. In Scenario 0, the MSW treatment includes the collection transport of the extra unsorted waste needed from the 287


multi-container system and composting includes the transport of the organic waste from the UCO filtration which takes place in the biodiesel production process. The sub-stage that makes the greatest contribution in Scenario 0 is composting (50.5%), mainly due to the sanitary landfill. The emissions from methane combustion generate a greater CFP than the avoided electricity production. A similar situation takes place in MSW treatment, accounting 39.7% of the overall GWP. Biodiesel production causes only 9.1% of the CFP, mainly because of the effect of methanol production. As the parameters UCO and organic wastecollection distances taken into account in the MC analysis for Scenario 0 only have influence on the sub-stage collection transport and its effect is negligible in the CFP (0.3%), the uncertainty due to these key parameters is not relevant. Most of the uncertainty is generated by the parameters related to composting (power consumption and organic fraction in sorting). The uncertainty is more relevant when analyzing Scenario 1. As can be observed in Figure 4 the prevailing sub-stage is electricity production: whereas the total CFP is -0.337 kg CO2-eq/FU, this sub-stage generates an impact of -2.457 kg CO2-eq/FU, accounting 53.7% of the overall impact in absolute terms. This carbon uptake is partially compensated by the GHG emissions from the other sub-stages. The contribution of anaerobic digestion is also important (35.1%) because of the methane losses. The electricity production is the sub-stage with the greatest effect in the CFP; it depends directly on the CHP engine sub-stage and, subsequently, on the process of anaerobic digestion as it produces the biogas which feeds the engine. Thus, the most influential key parameters in the CFP uncertainty are biogas production yield in anaerobic digestion and electricity yield of the CHP engine. In fact, the greatest variability is found for the GWP as an input, arising directly from the effect of the most uncertain parameters that affect electricity production. The contribution of the collection distances to global uncertainty is again negligible in Scenario 1.

4. Discussion According to the mean values, the reduction in the impact category caused by Scenario 1 is 106.6% showing that, despite the uncertainty in some process parameters, the CFP is distinctly improved by the alternative waste management system proposed. Although the uncertainty is not critical in the comparison between the scenarios under study, introducing the MC method increases the reliability of the results thereby helping the decision making. In this sense, reducing the uncertainty in the key parameters biogas production yield and electricity yield is especially important, since they influence the production of electricity, which greatly influences the overall results. Taking into account that the biogas production yield directly depends on the organic digester feed, and the organic waste from restaurants and catering is very heterogeneous, it would be difficult to control this parameter. However, the variability in electricity yield would be easy to reduce by implementing standardized CHP engines, since the one used in the Integral-b project is a special one adapted for the pilot plant. As far as the alternative system proposed in Scenario 1 and the facilities involved are concerned, historical data should be collected for as many process parameters as possible. A greater availability of historical data 288


would allow more representative probability distributions to be built for the MC analysis. It can also be useful to gather accurate information about the key parameters concerning the conventional management systems considered in the reference scenario (organic fraction in sorting and power consumption in composting). The collection distances of UCO and organic waste from restaurants and catering have not proved to be very influential. However, in order to implement this system, the collection processes should be optimized. In this sense, it could be very helpful to locate containers in each production spot, establishing a proper door-to-door system, which would reduce collection distances per FU but could increase the impact due to the maintenance of containers. This point should be studied by means of comparative LCA studies. In order to better assess the environmental profile of the process proposed other impact categories must be studied. In addition, as the ultimate goal of the Integral-b project is to influence the decision-making process, it must be taken into account that waste management activities constitute a cost for society since they require an investment from the public sector. Thus, an economic assessment would help to identify the system that reduces public expenses, considering uncertainty in the most influential prices.

5. Conclusions In this study, an LCA has been carried out to compare the CFP of two alternative systems for the management of organic waste (including UCO) from catering and restaurants in Spain. The process proposed by the Integral-b project aims to treat both types of waste jointly: UCO by biodiesel production and the organic waste by anaerobic digestion. This second sub-stage allows a cogeneration system to be established, improving the viability and sustainability of the whole process. In addition, the surplus of glycerin from the transesterification is used as a fuel in the CHP engine, avoiding its treatment as a waste. For the above-mentioned reasons, the integrated process follows the targets of the Directive 2008/98/EC, since guarantees the proper treatment of these kinds of waste. The Integral-b system has been compared to a reference one and a MC based uncertainty analysis has been implemented to identify the most robust management system. Although in this case the uncertainty does not influence the comparative assessment, it is important to analyze to what extent the studied processes are affected by data uncertainty in the inventory in order to reinforce the results for decision makers.

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management

with

consideration

of

uncertainty.

J

IndEcol

8(4):155-172.

Doi: 10.1162/1088198043630531 Kim S and Dale BE (2005) Life cycle assessment of various cropping systems utilized for producing

biofuels:

bioethanol

and

biodiesel.

Biomass

Bioenerg

29:426-439.

Doi:

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7. Tables Table 1. Summary of mean and uncertainty distributions of key parameters in both scenarios. Scenario 0

Scenario 1

Modelparameters

Mean

Uncertaintydistribution

Mean

Uncertaintydistribution

UCO collectiondistance (km)

100

Uniform (50, 300)

100

Uniform (50, 300)

Organic waste collection distance (km)

30

Uniform (30, 150)

30

Uniform (30, 150)

Organicfraction in sorting

0.8

Uniform (-5%, +5%)

384

Uniform (-5%, +5%)

187

Uniform (160, 232)

Methanecontent in biogas (%)

67.6

Uniform (60, 68)

Electricity yield of the CHP engine (%)

35

Uniform (32, 36)

Digester sludge transport distance (km)

25

Uniform (25, 150)

Power consumption in composting (MJ/t organic waste) 3

Biogas production yield in AD (m /t organic waste)

8. Figure captions Figure 1. System delimitation and flowcharts of the studied process in Scenario 0. Figure 2. System delimitation and flowcharts of the studied process in Scenario 1. Figure 3. Box-and-whisker plots of the carbon footprint from the Monte Carlo simulation of both Scenarios 0 and 1. The bold line in the middle of the box shows the median value, the box shows the percentiles and the other two wide lines are the 10 th and the 90th percentiles of the probability distribution of the carbon footprint. Figure 4.Contribution of the constitutive processes to the carbon footprint, according to the mean value of the impact per inhabitant and year.

292


9. Figures

Figure 1

Figure 2 GWP input (kg CO2-Eq./inhab·year)

GWP output (kg CO2-Eq./inhab·year)

293


5

3

4,5 2,5

4 3,5

2

3 2,5

1,5

2 1

1,5 1

0,5

0,5 0

0 Scenario 0

Scenario 1

Scenario 0

Scenario 1

Figure 3 GWP (kg CO2-eq/inhabitant·year) 5,00E+00

4,00E+00

3,00E+00

Composting 2,00E+00

MSW Treatment Electricity production

1,00E+00

CHP engine Anaerobic digestion

0,00E+00

Biodiesel production Scenario 0

Scenario 1

Collection transport

-1,00E+00

-2,00E+00

-3,00E+00

Figure 4

294


Carbon footprint of beef production in a brazilian south farm Clandio F. Ruviaro*1, Cristiane Maria de Léis2, Júlio Otávio Jardim Barcellos3 and Homero Dewes1 1

Center for Research in Agribusiness, CEPAN, UFRGS, Porto Alegre, Brazil

2

Environmental Engineering Program, UFSC, Florianópolis, Brazil

3

Center for Research on Systems of Beef Cattle Production and SupplyChain, NESPRO, UFRGS, Porto

Alegre, Brazil

*Corresponding Author: [email protected] *1,2,3 Postal address: Universidade Federal do Rio Grande do Sul Centro de Estudos e Pesquisas em Agronegócios (Cepan) Av. Bento Gonçalves, 7712 - Prédio da Agronomia Porto Alegre – RS – Brazil – Cep.: 91.540-000

Abstract The carbon footprint of beef production is one of the most widely discussed environmental issues within the current agricultural community due to its association with climate change. The goals of this study were to evaluate, by Life Cycle Assessment, the potential impact of beef production systems upon the environment and to estimate the carbon footprint of beef cattle production on a farm in the Western Frontier region of Rio Grande do Sul State. Aberdeen angus beef-bred cattle were assigned to one of seven scenarios: I) natural grass; II) improved natural grass; III) natural grass plus ryegrass; IV) improved natural grass plus sorghum; V) ryegrass and sorghum pasture; VI) intensified natural grass; and VII) intensified natural grass with supplement. The carbon footprint varied with the scenario and ranged from 18.47 to 37.18 kg CO 2 equivalent/kg live weight gain for the complete beef production system, including the contributions of cows, calves, and steers. Excluding emissions from pregnant cows, the carbon footprint ranged from 13.6 to 32.1 Kg CO2 equivalent/kg live weight gain. The results suggest that some production systems of beef cattle in the western frontier of Rio Grande do Sul have lower greenhouse gas emissions. The differences in estimated carbon footprint resulting from feed and method of calculation indicate that it is necessary to be prudent when extrapolating or comparing the obtained values among studies. It is important to recognise that the values cannot be extended to take into account the relative biodiversity of different Brazilian regions. Keywords: Supply Chain, GHG, livestock, meat, environment, consumer, sustainability

1. Introduction Beef cattle production is one of the most important agricultural activities in the world, 295


characterised by large numbers of animals and extensive pasture. The Brazilian herd has 205 million head occupying 170 million hectares of pasture, according to the most recent census of the Brazilian Institute of Geography and Statistics (IBGE, 2008). In the state of Rio Grande do Sul, there are approximately 13.2 million head of cattle occupying 11.7 million hectares, which is approximately 53.7% of the total area of the state (IBGE, 2008). The beef production relies on the management of natural pasture as the main source of animal feed. These grasslands have high biodiversity and are characterised by high production and quality during the spring and summer and low production and quality in the autumn-winter, when it is necessary to use cultivated pastures or supplementation. This seasonal efficiency combined with the media constantly highlighting beef cattle in general as a major source of emission of greenhouse gases, has generated actions to reduce its dimensions or minimise its negative impacts. Emissions from cattle are attributed to production processes that involve the inputs (CO2 and N2O) and production itself. Regarding the latter, methane emissions (CH4) are produced through enteric fermentation and manure, and nitrous oxide emissions (N2O) are emitted by faeces and urine. There is also the possible use of nitrogen fertilisers in pastures (Luo et al., 2010). Among these greenhouse gases, the most important is methane (Beauchemin et al., 2008; Biswas et al., 2010; Steinfeld et al., 2006). In Brazil, approximately 70% of methane emissions are derived from cattle production (MCT, 2010). Most of the methane has its origin in enteric fermentation and is a normal result of digestion in ruminant animals. It represents, in part, the inefficient capture of energy contained in animal feed. The use of techniques such as intensification of activity through appropriate management of the pastures and improved quality of food supplied to animals mitigates the production of greenhouse gases (Bungenstab, 2012; Harper et al., 1999;McAllister et al., 2011; O'Hara et al., 2003). Therefore, better pasture management, supplementary feeding practices, the substitution of forage for food containing less fiber, adequate sanitary control, integrated management of animal wastes, and the genetic improvement of the performance of the animals are techniques that may improve livestock productivity and reduce emissions linked to beef cattle production (Barioni et al., 2007; Boadi et al., 2004; Iqbal et al., 2008; Oliveira et al., 2007; Pedreira et al., 2004; Segnini et al., 2007; Wilkins and Hump, 2003). The aim of this study was to quantify and analyse the greenhouse gas (GHG) emissions (as carbon footprint) per functional unit (FU) for a typical south Brazilian beef production system. To attain this required (a) defining a typical beef production system operating in South Brazil; (b) defining the system boundary and functional unit; and (c) using the dietary and scenario options employed in South Brazilian beef production that may lead to reduced GHG emissions. Contribution to climate change associated with 7 different production systems was evaluated using an LCA approach ( Finnveden et al., 2009; Guinée et al., 2001). The original use of the LCA study was to associate default data provided by IPCC (2007) for CO2, CH4, and N2O emissions related to feed and animal dung with those now available in Brazil from EMBRAPA (Lima et al., 2012;MCT, 2010).

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2. Methods 2.1 Definition of the production system

This study was conducted at a farm in the Western Frontier region of the state of Rio Grande do Sul, Brazil. This region has the largest beef cattle herd (3,285,590 head), approximately 22.2% of the total cattle herd in this state (IBGE, 2008). The climatic classification is wet subtropic Cfa in Koeppen classification (Koeppen, 1948). The average precipitation is 1598 mm yr, without dry season. The average annual temperature is 19.8Celsius. Cattle are bred extensively, forage on natural and cultivated pasture with variable stocking rates and are responsible for most of the meat production in the region. In addition to natural grass, other pastures for beef cattle feed include improved natural grass (a mixture of natural grass, ryegrass and clover), ryegrass and sorghum. All the farmed animals are of the Bos taurus breed (Aberdeen angus). It was assumed that calves are weaned at approximately 180 days and that from this period onwards, they graze on grass. From 180 days to when the fattening weight is attained, the animals are allowed to graze on grass according to the scenarios defined forward (described in item 2.5). The animal fattening weight was 430 kg live weight for all scenarios. The data used (average of 6 years from 420 animals) reflect the reality of cattle farms with varied production systems in the region. 2.2 The system boundary and functional unit

The system boundary is defined by the GHG emissions associated with South Brazilian beef production from "cradle to farm-gate". The LCA of the production systems included natural grass, cultivated forages (natural grass plus ryegrass and clover, ryegrass, or sorghum), natural grass supplemented with proteinic-energetic mineralised salt and the resources used to produce these components (e.g., diesel and fertilisers), and all transportation, including the transport of components to the farm where they were consumed by the herd. Data concerning resource use and emissions associated with the production and delivery of several requirements for forage cultivation (fertilisers, diesel, and agricultural machinery) were obtained from the Ecoinvent database, version 3.0 (Nemecek et al., 2007). The model includes the physical limits of the beef unit and associated activity: emissions associated with nitrogen fertiliser production, transportation and application; emissions associated with animals; and emissions associated with the diesel used for agricultural work on the ranch. The following GHG sources were considered: on-farm CH4 emissions from cattle and manure; on-farm N2O emissions from manure and soils; and run-off and volatilization of indirect N2O emissions. The emissions associated with the production of medicines and pesticides are excluded due to absence of data (Cederberg and Mattsson, 2000). CO2 from enteric fermentation was excluded from the study because this enter a cycle comprising the uptake of atmospheric carbon by crops followed by a return to the atmosphere through animal respiration (IPCC, 2007). Thus, this gas is 297


considered neutral with respect to GHG emissions. In this study, the functional unit used for all flows within the system studied was ―1 kg live weight gain (LWG) at the farm gate‖. This functional unit serves as the measure of the performance of a production system to which all inputs and outputs are related. 2.3 Impact category

The global warming potential (GWP) over a 100-year time horizon was used to determine the contribution of CO2, CH4 and N2O to the greenhouse effect (IPCC, 2007). Carbon footprint was estimated by the average of regional beef using a standardised method of LCA (ISO, 2006a, 2006b) to calculate the environmental impact of a product from a life cycle perspective. Carbon footprint estimation through Life Cycle Assessment (Crosson et al., 2011; Čuček et al., 2012) considers the resources used in production, as well as the production of gases during the production process and from production to consumption (Peters et al., 2010). All calculations were performed in Excel using the LCA software tool SimaPro 7.3.2 (PRéConsultants, 2010). These gases have different global warming potential when converted to carbon dioxide equivalents. Each kg of carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) released to the atmosphere is equivalent to 1 kg, 21 kg and 298 kg of carbon dioxide, respectively. The analysis of carbon footprint identifies areas where emissions may be reduced by improved efficiencies, estimates the amount and breakdown of GHG emissions and provides a mechanism to track efforts in improving efficiencies and reducing emissions.

2.4 Emission factors

Enteric methane emissions were calculated using the equations from IPCC (Dong et al., 2006). Input data in this model are the animal live weights and were used to estimate the energy required for maintenance, beef yield to estimate the energy required for production, energy content in feed intake, and proportions of roughage feed and crude protein in the total dry matter intake (DMI) (Dong et al., 2006; NRC, 2000). Emission factors (EFs) for N 2O from dung were based on data from Primavesi et al. (2012). Over the duration of each life cycle stage in all production systems, the environmental inventory was limited to emissions of enteric CH4, emissions from N (urea), and emissions from manure. The emissions from animals were calculated according to the data from chapter 10 of the IPCC (Dong et al., 2006) using equation 10.21, 10.23, 10.24, 10.25 and Table 10.17. Methane emissions from manure and excreta deposited on the field during grazing were calculated according to Tier II protocols from the IPCC guidelines (IPCC, 2007). The emission factors and methane conversion factors (MCFs) were calculated following Tier II protocols and adjusted following the analysis protocols in Lima et al. (2006) and MCT (2010). Tier II protocols were employed to calculate the enteric methane emissions because of the sensitivity of emissions to the production system and the importance of methane emissions to overall GHG emissions in beef cattle production. In this study, a 6% conversion factor (Ym) was applied to the pasture data (Dong et al., 2006; Johnson and Johnson, 1995;Primavesi et al., 2012). The production of manure was calculated based on 298


DMI with digestibility varying according to the forage type in each production system (Peripolli et al., 2011; Valadares Filho et al., 2010). Direct emissions of nitrous oxide (N2O) from soil and EF values were calculated as recommended by the IPCC (2007) with adjustments as in Alves et al. (2012) using equation 11.2 and 11.5 from chapter 11 using the measured nitrogen intake and nitrogen retained. The nitrogen applied to soil as fertiliser was calculated as nitrogen in urea, as recommended by SBCS (2004). The nitrogen in excreta was calculated as the total amount of N in feed dry matter intake (DMI) minus the amount of N in beef (calves and growth). The indirect emissions of N 2O caused by volatilization of NH3 and leaching of nitrate (NO3) were estimated using EF values according to the IPCC (2007).

2.5 Scenarios for carbon footprint estimation

Scenarios were developed using Angus beef-bred animals utilised in typical South Brazilian beef production systems as castrated males. The system was then modified to consider the life cycle from pregnant cows (281 days) to fattened steers with a 430 kg final live weight in all scenarios (Table 1). Scenario I analysed animals in natural grass for a period of 840 days. In Scenario II, the animals grazed on improved natural grass for 510 days. In Scenario III, the animals grazed on natural grass for 510 days plus 159 days on ryegrass. In Scenario IV, the animals grazed on improved natural grass for 360 days plus 125 days on sorghum. In Scenario V, the animals grazed on cultivated ryegrass and sorghum for 502 days. In Scenario VI, the animals grazed on natural grass supplemented with proteinic-energetic mineralised salt for 510 days. In Scenario VII, the animals grazed on natural grass supplemented with proteinic mineralised salt for 660 days. Table 1: Schedules of the live weight, live weight gain, duration from calving to fattening and stock rate of each scenario. Age, mo

Live weight, kg

DMID, kg/d

Scenario

6

12

18

24

30

I

165

195

280

325

430

II

190

330

430

-

-

III

165

195

280

430

-

IV

190

330

430

-

-

V

190

330

430

-

-

VI

220

260

430

VII

220

260

360

430

-

I

1,02

1,84

2,42

3,36

3,37

II

1,50

3,57

4,83

-

-

III

1,02

1,84

2,42

5,59

-

IV

1,15

3,58

4,83

-

299


V

1,10

3,47

4,99

-

-

VI

1,31

2,49

3,77

-

-

VII

1,31

2,49

3,15

4,45

total

Live weight gain, kg

Period, d

I

133

30

85

45

105

398

II

158

140

100

-

-

398

III

133

30

85

150

-

398

IV

158

140

100

-

-

398

V

158

140

100

-

-

398

VI

188

40

170

-

-

398

VII

188

40

100

70

-

398

I

180

150

180

150

180

840

II

180

180

150

-

-

510

III

180

150

180

159

-

669

IV

180

180

125

-

-

485

V

180

180

142

-

-

502

VI

180

150

180

-

-

510

VII

180

150

180

150

-

660 means

Live weight supported, kg/ha

I

397

397

397

397

397

397

II

716

716

716

-

-

716

III

397

397

397

930

-

530

IV

716

716

1150

-

-

861

V

930

930

930

-

-

930

VI

380

380

380

-

-

380

VII

380

380

388

380

382

3. Results and Discussion Evaluation of strategies for mitigation and adaptation usually occurs at scales at which interventions can be performed (the production system, region or country). Recent publications have used Life Cycle Assessments to determine all or a portion of the GHG emissions from measured inputs and outputs over beef production systems (Avery and Avery, 2008;Beauchemin et al., 2011; Cederberg et al., 2011; Dollé et al., 2011; McAllister et al., 2011;Schils et al., 2007; Sejian et al., 2011; Place and Mitloehner, 2012; Veysset et al., 2010). The application of and comparisons among existing LCA can be limited due to differences in goals, system boundaries or functional units. Creating LCA models that account for different management strategies and

300


technology is critical, as there is increasing consumer interest in sustainable beef production and there is a need for a complete analysis of these different systems. In this study, the estimated carbon footprint of one cattle farm in the Western Frontier region of Rio Grande do Sul State ranged from 18.47 to 37.18 kg CO 2-e/kg LWG (Table 2) for a complete beef system including the contributions of cows, calves, and steers. Excluding emissions from pregnant cow, the estimated carbon footprint ranged from 13.6 to 32.1 Kg CO 2-e/kg LWG. The results indicate that when viewed on an equal live-weight production basis, scenario I (natural grass), with 37.18 kg CO2-e/kg LWG, is more greenhouse gas intensive than scenario V (cultivated ryegrass and sorghum), with 18.47 kg CO 2-e/kg LWG. The least CO2-e emitting production systems were scenario V and II, with 18.47 and 18.67 CO2-e/kg of LWG, respectively, producing fattened animals in 485 and 510 days, respectively. These results are close to those reported by Phetteplace et al. (2001), who estimated 15.5 kg CO2-e/kg live weight for calf-to-beef systems. Our results are also similar to estimates by Casey and Holden (2006) and Veysset et al. (2010) of 11 and 15 kg of CO2-e/kg of live weight gain, respectively. Hacala and Le Gall (2006) estimate a carbon footprint between 11.33 and 14.69 kg CO 2-e/kg live weight in three suckler systems. Studies evaluating the carbon footprint of beef production in Japan (Ogino et al., 2004), Sweden (Koneswaran and Nierenberg, 2008) and Brazil (Cederberg et al., 2009), have also reported similar values of total GHG emissions as in the current study, ranging from 22,8 kg of CO2-e/kg of beef to 32.3 kg of CO2-e/kg of beef.

Table 2: Summary of the calculated CO2 equivalent inputs from each growth stage of each scenario. excluded Age, mo

total

pregnancy cow

CO2 kg

Scenario

Cow

0-6

6 - 12

12- 18 18 - 24

24 - 30

emissions emissions

I

4,87

3,51

8,07

5,52

8,55

6,66

37,18

32,31

II

4,87

3,34

3,83

6,63

-

-

18,67

13,80

III

4,87

3,51

8,07

5,52

3,80

-

25,77

20,90

IV

4,87

3,34

8,07

6,49

-

-

22,77

17,90

V

4,87

3,48

3,78

6,34

-

-

18,47

13,60

VI

4,87

2,20

8,05

5,18

-

-

20,30

15,43

VII

4,87

2,20

8,05

6,03

7,78

-

28,93

24,06

equivalent, CO2

weight gain

e/live

The highest CO2-e emissions were from scenarios I and VII. These produced 37.18 and 28.93 kg CO2-e/kg LWG, respectively, with fattening periods of 840 and 660 day, respectively. These scenarios had the lowest dry matter intake digestibility (DMID) of 48%. Among all grasslandbased cattle farms, those production systems with DMID from 52 to 59 % achieved the lowest 301


CO2-e emissions and highest feed conversion rate. This means that they generate lower CH 4 and N2O emissions per production system. The high values of approximately 27 kg of CO 2-e per kilogram of body weight gain, scaled with intensity of production, were reported in a study by Nguyen et al. (2010). Importantly, it is necessary to consider the relative intensity of the production system, the stocking rate (number of animals raised and produced per hectare) and the kilogram of body weight gain obtained per hectare as the main drivers of the greenhouse gases emissions. The most intensive production systems, those with scenarios II, IV, V and VI with 510, 485, 485 and 510 days for producing fattened animals and a stocking rate of 716, 861, 930 and 380 kg/ha, respectively, are the lowest CO2-e emitting scenarios (Table 1). Scenario VI produces lower emissions (20.3 kg CO2-e/kg LWG) despite the low DMID (48%). The proteinic-energetic mineralised salt used led to these results because it acts as an amender in the feed conversion rate and reduces the time to achieve the fattening weight (510 days). These results are consistent with those of other studies that have shown that higher quality forage, the use of concentrated, essential oils or increased growth rates reduce methane and nitrous oxide emitted from manure, both of which are key emission gases (Benchaar and Greathead, 2011; Casey and Holden, 2006; Lovett et al., 2005). Comparisons of these results with previous studies reveal a number of difficulties. First of all, in Brazil there only a few studies concerning beef production using Life Cycle Assessment methodology (Ruviaro et al., 2012). One very significant problem is the variation in choice of functional unit and time scale among studies (de Vries and de Boer, 2010). For example, a study of a Japanese beef fattening system (Ogino et al., 2004) estimated a 32.3 kg CO2-e/kg of beef gain during the fattening of the animal, but this did not include cow emissions for the whole system. Furthermore, it should be noted that the production efficiency in the Japanese cattle system was very different from that in this study. In another recent study of Brazilian beef cattle, Cederberg et al. (2011) estimated a carbon footprint from beef cattle production in the Legal Amazon Region. However, Cederberg et al.'s estimates are not adequate for comparison because they assumed calving intervals of 20 months and 3-4 years to fattening. This is an inefficient production system that is used in a specific region and does not represent Brazilian norms. These issues make it difficult to compare the results among studies because of differences in management practices and assumptions regarding the production systems in other countries (Beauchemin et al., 2011; Crosson et al., 2011; Roy et al., 2009). Considering the variation among published studies from the point of view and specific methodology of collection and analysis of data, we recognize that the results from specific regions cannot be used to compare beef production scenarios in different regions of the world. Comparison of the various studies emphasises the effect of each production system and variation in efficiency on the estimated environmental impact.

302


4. Conclusions The results suggest that some production systems of beef cattle in the western frontier of Rio Grande do Sul have lower GHG emissions. Improvements in pasture quality, genetic selection for animals with high feed conversion rates, promotion of better pasture management, use of additives and establishment of integrated crop-livestock systems are factors for mitigation of the emissions of greenhouse gases. Likewise, the results of the research indicate that to obtain an accurate application of the LCA, it is necessary to estimate the flow balance of the greenhouse emissions at the different scenarios and regions. It also means that Brazil needs to develop methodologies, elaborate inventories based in the IPCC Tier 3, allowing, thus, for a more detailed estimate of emissions and removals and calculate the amount of land occupied and the variation of the carbon storage in the soil, since they reflect directly in the results obtained in the LCA. Also, considering the great biodiversity of the Brazilian regions, it is essential to make some adjustments concerning the IPCC equations for calculating the greenhouse gas emissions within the conditions of tropical and subtropical climate. Further, it should be noted that this is a first approximation of the impacts associated with the typical beef production systems by LCA. It is recommended that additional studies be conducted on a number of scenarios in order to improve the accuracy of results and fill in data gaps. Also, further research for more Brazilian-specific emission factor data may be warranted for the next iterations. Given that it is difficult to assess the carbon footprint of any production system alone, considering the lack of baseline data in Brazil, this study can become a standard for future LCA studies.

Acknowledgments:CAPESand CNPq, Brazil

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Life Cycle Assessment of Bioethanol Production from Eucalyptus globulus: Comparison of Solvent Extraction and Dilute Acid Hydrolysis Marjorie Moralesa,b, Julián Quinteroa,b, Felipe Scotta,b, Raúl Conejerosa, Germán Aroca*a a

Escuela de Ingeniería Bioquímica, Pontificia Universidad Católica de Valparaíso, General Cruz 34,

Valparaíso, Chile. www.eib.cl b

Bioenercel S.A. Barrio Universitario s/n, Concepción, Chile. www.bioenercel.com

Abstract In this work the Life Cycle Assessment of the ethanol production from Eucalyptus globulus with two pretreatment technologies was accomplished with the aim of determining the influence of pretreatment selection on environmental performance of the process. To compare solvent extraction and dilute acid pretreatments, this study addressed the potential impacts per kg of ethanol produced. Inventories were obtained by combining SimaPro 7.3 with materials and energy flow information obtained from process simulation models of 2,000 t/day of dry wood. Processes involved: pretreatment, liquor separation and pulp washing, simultaneous saccharification and fermentation, ethanol recovery and biological wastewater treatment. Ethanol yield were 161 and 209 kg/t of dry wood for dilute acid and solvent extraction, respectively. The limits of the evaluated systems were defined as ―cradle to gate‖. The considered impact categories were: Abiotic depletion (AD), Acidification (A), Eutrophication (E), Global warming (GWP), Ozone layer depletion (OD), Human Toxicity (HT), Fresh water aquatic Ecotoxicity (FE), Marine aquatic Ecotoxicity (ME), Terrestrial Ecotoxicity (TE) and Photochemical oxidation (PO). Results showed that pretreatment technology had a clear effect on environmental impacts of the whole process. The production of ethanol with solvent pretreatment was found to be the option with the lowest impact in most categories (AD, E, GWP, OD, HT, FE, ME and TE)when compared to dilute acid. The energy ratios obtained were 6.9 and 5.3 for solvent extraction and dilute acid, respectively. Highest difference between both pretreatments was due to the abiotic depletion, eutrophication and ozone layer depletion impact categories, showing a notable influence of ethanol yield on the environmental performance of the process, because of the lower raw material requirements for producing a kilogram of ethanol.

Key words: life cycle assessment, ethanol, Eucalyptus globulus, dilute acid, organosolv, pretreatment.

1. Introduction Increasing concern about sustainability and global warming has prompted the search for new liquid fuels showing renewable, efficient and economically viable production. Although ethanol production from sugarcane and corn has raised continuously during the last 20 years, a dramatic *

Corresponding author: G. Aroca

Phone: +56 32 2273755 e-mail: [email protected] 309


increase in ethanol production from corn starch- based technology may not be desirable since corn production will compete for the limited agricultural land and fertilizers needed for food production (González- García et al. 2009). Although corn-based and sugar based-ethanol are promising substitutes to gasoline production mainly in the transportation sector, they are not sufficient to replace a considerable portion of the one trillion gallons of fossil fuel presently consumed worldwide each year (Limayem and Ricke 2012) and their use has been broadly discussed due to the effect in the global food market and the direct competition with land use for agriculture, therefore, affecting human‘s food security. Whereby, research efforts have been oriented to develop a process that use the residues from those raw materials or alternative carbon sources, such as forestry wastes, grasses, wastepaper, municipal wastes and various industrial wastes (Baral et al. 2012)

On the other hand, ethanol produced from lignocellulosic biomass such as perennial grasses, agricultural residues and wood could be produced locally, creating jobs and improving homeland energy sustainability and independence. However, although many processes for ethanol production have been disclosed, its technical and economical potential has not been established (Warhust 2002). Most of the models published in recent years have been developed for processes using dilute acid hydrolysis, steam explosion and AFEX pretreatment processes and incorporate advanced ethanol fermentation processes such as simultaneous saccharification and cofermentation (Andrews et al. 2009; Brundtland 1987; Hart and Ahuja 1996).

Although dilute acid hydrolysis pretreatment effectively separates hemicellulose from the lignocellulosic complex, is unable to remove substantial amounts of lignin. This compound has been related to pulp enzymatic hydrolysis impairment by either restricting swelling of the substrate, acting as a barrier to enzyme accessibility (González-García et al. 2012b) or by unproductive adsorption of cellulases thereby reducing the saccharification rate (Rahikainen et al. 2011). Lignin removal can be achieved, among other alternatives, by biomass fractionation using a hot aqueous organic solvent such as ethanol. Solvent extraction process (known as Organosolv) was initially developed by General Electric and the University of Pennsylvania to provide biofuels for turbine generators. Later, it was modified by the Canadian pulp and paper industry resulting in the Alcell® pulping process (IEA 2011). The process gained new relevance for biomass pretreatment for ethanol production, and is being currently developed by Lignol(Azapagic et al. 2006), under the assumption of possible income from high quality lignin that could be sold as a coproduct for various industrial applications (ISO 2009; RSB 2012). Considerable amounts of experimental research had been performed on using solvent extraction pretreatment for bioethanol production from wood (Azapagic et al. 2006; Humphreys et al. 2003; Inoue et al. 2010; Matos and Hall 2007). Several studies have been published in the last years regarding the assessment and calculation of the environmental performance of lignocellulosic bioethanol. The main purpose of these studies has been to compare the environmental impacts of lignocellulosic bioethanol with corn-based and sugar-based bioethanol and gasoline. In order to determine the effects of biofuels on the 310


environment as exactly as possible, the methodology of Life Cycle Assessment (LCA) is the most common methodology for analyzing and assessing the potential environmental impacts due to the production and use of the bioethanol, moreover, it allows to make a more effective strategic planning (Allen et al. 1997). The LCA is a process of compilation and evaluation of the inputs as energy and resource consumption, outputs as pollutant emissions and the potential environmental impacts of a product system throughout its life cycle (Zah et al. 2007). The results obtained applying LCA allow to compare process, products and services currently available or projected. LCA can identify potential impacts at an early stage of a process design, and provides the opportunity for making decisions for improving its sustainability before the process be implemented (Quintero et al. 2008). In this work the Life Cycle Assessment of the ethanol production from Eucalyptus globulus with two pretreatment technologies was accomplished with the aim of determining the influence of pretreatment selection on environmental performance of the process.

2. Methodology LCA is a methodology for the comprehensive assessment of the environmental impact associated to a product or process throughout its life cycle (from extraction of raw materials to product disposal at the end of use) (Curran 2007). This methodology considers four stages according to the ISO standards (ISO 2006a, b): Objective and Limits of the System, Life Cycle Inventory, Life Cycle Impacts and Analysis and Interpretation. LCA methodology is a comparative tool, which is especially useful for decision making between process or product alternatives. However, comparative analysis requires that the alternatives have the same functional unit, it means that it should be possible to select the same base of analysis in the alternatives. Although, the results from the analysis can be independently visualized for each evaluated system, these are mainly useful for comparative analyses. 2.1 Goal and scope definition

In this work the Life Cycle Assessment of the ethanol production from Eucalyptus globulus by two pretreatment technologies was accomplished with the scope of determining the influence of pretreatment selection on environmental performance of the process. The pretreatment evaluated were Solvent Extraction (SE) and Dilute Acid Hydrolysis (DA). Regarding to the impact assessment, modeling was performed using SimaPro 7.3 and CML 2 baseline 2000 method. The considered impact categories were: Abiotic depletion (AD), Acidification (A), Eutrophication (E), Global warming (GWP), Ozone layer depletion (OD), Human Toxicity (HT), Fresh water aquatic Ecotoxicity (FE), Marine aquatic Ecotoxicity (ME), Terrestrial Ecotoxicity (TE) and Photochemical oxidation (PO). 2.2 Functional Unit (FU)

According to the ISO standards, the functional unit is defined as a quantified performance of a product system to be used as a reference unit in an LCA study (ISO 2006a, b). In this work, the FU 311


for each scenario was based on 1 kg of produced bioethanol. 2.3 System definition and boundaries

The system boundary of the bioethanol system includes the agricultural chain and the bioethanol production as cradle to gate boundary. To compare solvent extraction (SE) and dilute acid (DA), this study addressed the potential impacts per kg of ethanol produced. Inventories were obtained by combining SimaPro 7.3 with materials and energy balances calculated from process simulation models of 2,000 t/day of dry wood, using Aspen Plus V 7.1 to determine the compositions and flow rates of all the streams in a given process and its energy requirements.The selected capacity matches the one selected by the National Renewable Energy Laboratory (Chandel et al. 2007) so that processes can be compared without interference due to economies of scale. 2.3.1 Eucalyptus cultivation The data for eucalyptus cultivation was obtained from those reported by Curran (2007). In this study the forest operations took place in North-West Spain with a wood production of 5.2 t/ha year in a density of 1,428 plants/ha for a life cycle of 15 years including field management, planting, harvesting and cleaning. 2.3.2 Enzyme production Enzyme production inventory were obtained based on the National Renewable Energy Laboratory (NREL) report (Chandel et al. 2007). The author considered submerged aerobic fermentation of a T. reeseifungus on a feedstock of glucose and fresh water. They have assumed a media preparation step where a small fraction of glucose is converted to sophorose, an inducer of cellulase, using a small amount of the cellulase enzyme itself. 2.3.3 Process synthesis Processes under evaluation were synthesized in a previous a work (Warhust 2002) using literature information and conventional hierarchical process synthesis (Wyman et al. 2005). The first process (SE) incorporates organic solvent (ethanol) pretreatment, liquor separation and pulp washing, simultaneous saccharification and fermentation (SSF) of the cellulose-rich pulp, distillation, dehydration by adsorption on zeolites and biological wastewater treatment including anaerobic digestion for biogas production and aerobic treatment. Pretreatment section was synthesized using the conceptual design presented by Azapagic et al. (2006). SSF includes pulp liquefaction according to Kumar and Murthy (2012) and the remaining areas where designed based on 2011 NREL report (Chandel et al. 2007). The second process (DA) integrates co-current dilute-acid hydrolysis, liquor separation and washing of the produced pulp, simultaneous saccharification and fermentation, distillation, dehydration and biological waste water treatment. Pretreatment and SSF designs were adapted from the hardwood chips ethanol production process presented by NREL (Kadam et al. 1999), while the remaining areas are consistent with SE design. In both processes, SE and DA, the use of the pretreatment reaction liquor, containing xylose, was not incorporated for ethanol production. Hence no overliming or ion exchange for inhibitor removal of the 312


separated reaction liquor was considered. Process schemes for ethanol production using SE and DA are shown in Figures 2 and 3. Material composition (see Figure 1), in %(w/w) dry wood basis, was normalized from the data obtained by Kadam (2000).Results from process simulations were used to size the process equipment and to estimate the operating expenditures in chemicals, solid disposition, process water, and labor. 2.4 Allocation

Allocation is a procedure to attribute environmental burden of multi-functional processes to their input or output flows of the product under study; this is one of the most critical issues in LCA (Aichele and Felbermayr 2012). It is calculated by assigning the material input or output to the obtained products (ethanol and electricity). The EcoInvent database provides flexibility to the users when selecting an allocation basis (Heijungs and Guinée 2007). This paper focuses on the issue of allocating over a economic-based approach, following the method recommended in the CML guide (Kodera 2007).Allocation was avoided in the case of solvent extraction pretreatment because all the electricity produced from wastes was consumed in the ethanol and enzyme production processes. Meanwhile, dilute acid hydrolysis pretreatment considered the allocation due to electricity (11%) and bioethanol (89%) production.

3. Results 3.1 Life cycle inventories

Tables 1 and 2 summarize the inventories of solvent extraction and dilute acid pretreatments, respectively. 3.2 Environmental impact assessment

Table 3 summarizes the LCA characterization results for each pretreatment under study. Figure 4 shows the differences between the two pretreatment alternatives. Results showed that the levels of emissions which contribute to AD, E, GWP, OD, HT, FE, ME and TE were reduced to a maximum of 36 % in the SE pretreatment when compared to DA. The impacts obtained for these categories in SE pretreatment, respect to the emissions involved in the dilute acid pretreatment, were 68%, 66%, 84%, 64%, 79%, 85%, 81% and 84%, respectively. However, reductions of 5% and 6 % were obtained for Acidification and PO in the dilute acid hydrolysis pretreatment. 3.2.1 Global warming potential and Acidification Contributions to GW and Acidification categories of the involved stages in life cycle of ethanol production are shown in Figure 5. According to Quirin et al. (2004), the GHG sources in the life cycle of bioethanol are: the agricultural stage (due to nitrogen fertilizers and to the fossil fuels required in the crops handling), transport and the bioethanol conversion stages. In this work, the process was the main contributor to GHG (see Figure 5a) with a 55% and 35% of the total emissions in SE and DA, respectively, followed by the enzyme production with 32% in both 313


pretreatments. Eucalyptus cultivation provides 28% and 13% of the total GHGs emissions for DA and SE, respectively. This difference is mainly due to emissions associated to the application of fertilizers and fossil fuels use, which were higher in the DA because of the higher feedstock requirement to produce 1 kg of bioethanol, however if pentoses fermentation in considered in the analysis the ethanol yield can be increased and the GHG emissions and Acidification impact related to the agricultural stage can be diminished. The transport presents a negligible contribution (less than 6%). Contributions to Acidification are shown in Figure 5b. The main substances, which contribute to acidification, are NOx and ammonia, derived from forest activities and use of fertilizers followed by others acids derived from the process activities such as H 2SO4 and SOx. The acidification was higher in the solvent extraction pretreatment in comparison to dilute acid pretreatment. The main contributor in the SE was the conversion process (76% of the total acidification emissions) while in the DA both eucalyptus cultivation and process conversion had similar impacts with values of 46% and 43% of the total contribution, due to the high forest activity necessary that equals the acidification emissions from the process activities. 3.2.2 Other impact categories Figure 6 shows the main stages of the life cycle assessment for the production of 1 kg of lignocellulosic bioethanol in different impacts categories. Concerning to AD (see Figure 6a) the conversion process and feedstock cultivation were the main stages contributing in this category, representing more than 70% of the totalAD for both analyzed pretreatments, followed by the enzyme production, due to the fossil fuel used in this stages.

Nitrogen oxides and ammonium emissions from the forest activities and the conversion process influenced the Eutrophication. Ammonia and nitrogen oxides were emitted in the eucalyptus cultivation while ammonium chloride was emitted in the conversion process. Figure 6b shows the results obtained for Eutrophication. In the case of SE pretreatment the conversion process represented 58% of the total impact of this category. While in the DA pretreatment, the emissions of ammonium chloride from the conversion process were negligible in comparison to SE, however the higher demand of feedstock caused a high output of ammonia and nitrogen oxides compounds of the forestry activity, representing 60% of the total eutrophication. As in the case of GHG and Acidification, the Eutrophication impacts can be diminished by including the pentoses fermentation in the conversion process for increasing the global ethanol yield.

Figure 6c shows the contribution of each stage to the OD. Hydrocarbons are substances with a higher effect on this impact category. The main contributor stages were forest activities and conversion process for SE, 38% and 41% of the total emissions contributing this category, respectively. On the other hand, the main contributor in DA pretreatment was the forest cultivation, with a share of 64% of the total emissions. These results are due to the fossil fuels required in the eucalyptus cultivation activities and process activities, in which the hydrocarbons 314


are involved.

With respect to Ecotoxicity Potentials, Figure 6 shows the main stages contributing to HT (see Figure 6d), FE (see Figure 6e), ME (see Figure 6f) and TE (see Figure 6g). The conversion process was the principal stage emitting substances that affect the HT, representing the 67% and 49% of the total impact to human health, for SE and DA, respectively. The results were similar in the other Ecotoxicity potentials, with contributions of the conversion process higher than 65%. Concerning the PO category, the main contributor was the conversion process; representing the 70% and 41%, follow by the forest stage with 13% and 37% for SE and DA, respectively. In the case of SE, there were higher diffuse emissions of acetic acid and ethanol used as solvent with a remarkable contribution to PO compared to DA pretreatment.

3.2.3 Energy Ratio Energy ratio determines if the bioethanol produced contains more useful energy than the fossil fuels required for producing it. In general, the energy ratio of a determined fuel, also called ―energy balance‖, is defined as the ratio of the heat content of the fuel (in MJ/kg) to the nonrenewable primary energy consumed to produce 1 kg of that fuel, the latter being evaluated over the entire life cycle of the fuel (Gnansounou and Dauriat 2005). Energy ratio value indicates if the lignocellulosic process requires more or less fossil energy when compared with the energy content of bioethanol, i.e. if the energy balance is lower or higher than 1. Table 4 shows the energy ratio obtained for both pretreatments, considering the main stages in the life cycle according to the boundaries established in the study (eucalyptus cultivation, transport and process). The energy ratios obtained were 6.9 and 5.3 for SE and DA, respectively, using the inventory of eucalyptus cultivation reported by González-García et al. (2012b). However, when the eucalyptus cultivation inventory from Ecoinvent database, included in SimaPro, was considered for the production of 1 kg of Eucalyptus ssp. with moisture of 50% (see Table 5), the results varies considerably to values less to 1, 0.7 and 0.9, for SE and DA, respectively.It was evidenced that the source of the inventories (depending on location and agricultural practices) highly influenced the energy balance of the life cycle of ethanol production.

4. Discussion Several studies have been published in the last years regarding the assessment and calculation of the environmental performance of lignocellulosic bioethanol(Cherubini and Jungmeier 2010; Cherubini and Ulgiati 2010; Dias et al. 2012; González-García et al. 2009; González-García et al. 2012a; González-García et al. 2012c). The main purpose of these studies has been to compare the environmental impacts of lignocellulosic bioethanol with corn-based and sugar based-bioethanol 315


and gasoline. The general trend observed has been the significantly GHG emissions reduction when this biofuel was compared with fossil fuels and these differences are dependent on bioethanol proportion in the gasoline-bioethanol blend and the raw material (Cherubini et al. 2009; Choudhury et al. 2002; Elsayed et al. 2003; GM/ANL 2001; González-García et al. 2009; González-García et al. 2012a; González-García et al. 2012c; Woods and Bauen 2003). However, the analysis must be addressed to the definition of feasible process stages, which will be able to achieve a positive energy balance and environmental sustainability. In the positive energy balance and its environmental sustainability aspects the pretreatment become relevant, due to its effect on the amounts of sugars available for conversion to ethanol, and then the bioethanol yield. In this study was remarked the importance of the correct choice of a pretreatment technology where the researchers need to work to improve the environmental performance. Concerning to the environmental results, the process with solvent extraction pretreatment shows better results in most of the evaluated impacts categories, which was correlated to the ethanol yield of 209 and 161 kg/t of dry wood for solvent extraction and dilute acid, respectively. Whereby, a higher feedstock requirement represents more environmental impacts, due to the forest activities, which represent the main contributor in acidification, eutrophication and ozone layer depletion categories, these results are in agreement to the obtained by others authors in the production of lignocellulosic raw materials(Edwards et al. 2007; Quirin et al. 2004; Zhi fu et al. 2003). Global environmental performance of proposed processes for the production of lignocellulosic bioethanol is still under discussion due to the state (level) of development of the technology, but it is important to remark that special attention is also necessary in the other stages of the conversion process, hydrolysis and fermentation, because the efficient conversion of all the sugars highly depends on the yields of each stage involved. In the same way, a better use of sugar (i.e. pentoses fermentation) could increase the ethanol yield leading to a lower feedstock requirement and then to lower environmental impacts in the bioethanol life cycle.

5. Conclusion Results showed that pretreatment technology has a clear effect on environmental impacts of the whole process, being in this work solvent extraction the best option. The highest difference is due to the abiotic depletion, eutrophication and ozone layer depletion impact categories, showing a notable influence of ethanol yield on environmental performance of the process, due to the lower requirements of raw materials, and therefore lower emissions from the forest and process activities required for producing 1 kilogram of ethanol. The uncertainty in inventory data of the eucalyptus cultivation shows the necessity of establishing a proper inventory according to the particular context of evaluation, because it represents a high influence in the LCA results. It means that a better inventory must be obtained from the Country and region in evaluation, with the aim of establishing the better forest activities and conversion processes, which in turns could varies from place to place.

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6. Acknowledgements Work founded by Grant 08-CTE ConsorcioBioenercel from CORFO INNOVA 208-7320, Chile.

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Life cycle implications of fuel oxygenate production from California biomass, National Renewable Energy Laboratory Golden, NREL Report no. NREL/TP-580-25688. Colorado, USA. Kodera K (2007) Analysis of allocation methods of bioethanol LCA. Amsterdam: Leiden University Kumar D, Murthy G (2012) Life cycle assessment of energy and GHG emissions during ethanol production form grass straws using various pretreatment process. Int J Life Cycle Ass 17:388-401. doi:10.1007/s11367-011-0376-5 Limayem A, Ricke S (2012) Lignocellulosic biomass for bioethanol production: Current perspectives, potential issues and future prospects. Prog Energ Combust 38:449-467. doi:10.1016/j.pecs.2012.03.002 Matos S, Hall J (2007) Integrating sustainable development in the supply chain: The case of life cycle assessment in oil and gas and agricultural biotechnology. J Oper Manag 25:1083-1102. doi:10.1016/j.jom.2007.01.013 Quintero JA, Montoya MI, Sánchez OJ, Giraldo OH, Cardona CA (2008) Fuel ethanol production from sugarcane and corn: Comparative analysis for a Colombian cas. Energy 33:385-399. doi:10.1016/j.energy.2007.10.001 Quirin M, Gärtner S, Pehnt M, Reinhardt GA (2004) CO2 Mitigation through Biofuels in the Transport Sector. Status and Perspectives, Institute for Energy and Environmental Research Heidelberg (IFEU), Germany Rahikainen J, Mikander S, Marjamaa K, Tamminen T, Lappas A, Viikari L, Kruus K (2011) Inhibition of enzymatic hydrolysis by residual lignins from softwood study of enzyme binding and inactivation on lignin-rich surface. Biotechnology and Bioengineering 108:2823-2834. RSB. The Roundtable on sustainable biofuels. Lausanne. Switzerland2012. Warhust A (2002) Sustainability Indicators and Sustainability Performance Management, International Institute for Environment and Development. World Business Council for Sustainable Development, Warwick, U.o. 43. UK Woods J, Bauen A (2003) Technology status review and carbon abatement potential of renewable transport fuels in the UK, Imperial College London, Technology-ICEPT, C.f.E.P.a. London, UK Wyman C, Dale BE, Elander R, Holtzapple M, Ladisch M, Lee YY (2005) Coordinated development of leading biomass pretreatment technologies. Bioresource Technol 96:1959-1966. doi:10.1016/j.biortech.2005.01.010 Zah R, Böni H, Gauch M, Hischier R, Lehmann M, Wäger P (2007) Life Cycle Assessment of Energy Products: Environmental Impacts Assessments of Biofuels, Empa Technology and Society Lab, Switzerland Zhi fu G, Chan A, Minns D (2003) Life Cycle Assessment of Bio-ethanol Derived from Cellulose. Int J Life Cycle Ass 8:137- 141. doi:10.1007/BF02978458

319


Table 1. Inventory for lignocellulosic ethanol production (solvent extraction pretreatment) Materials Unit Value

Input from Environment Water

kg

34,8

Air

kg

240,8

Feedstock

kg

2,1

Sodium hydroxide

g

97,5

Sulphuric acid

g

74,5

Lime

g

48,4

Sodium sulphate

g

0,8

Enzyme

g

37,9

Chemicals inorganic

g

0,1

kg

1

Sludge

g

26,8

Limestone waste

g

9,43

Used air

kg

237,4

Carbon dioxide, biogenic

kg

5,5

Ammonium chloride

g

21,4

Sodium sulfate

g

57,6

Water

kg

38,9

Sulfuric acid

g

58,7

Acetic acid, sodium salt

g

17,9

Methane, biogenic

mg

0,3

Sulfur dioxide

mg

0,8

Acetic acid

mg

0,8

Sodium hydroxide

mg

0,6

Others Organic compounds

g

0,5

Input from Technosphere

Output to Technosphere Material Ethanol Wastes to treatment

Output to Environment

320


Table 2. Inventory for lignocellulosic ethanol production (dilute acid pretreatment) Materials Unit Value

Input from Environment Water

kg

695,8

Air

kg

768,0

Feedstock

kg

6,2

Sodium hydroxide

g

121,6

Sulphuric acid

g

68,5

Lime

g

62,1

Enzyme cellulase

g

49,3

g

0,2

Ethanol

kg

1,0

Electricity (MJ)

MJ

9,9

Sludge

g

57,4

Wood Ashes

g

397,4

Used air

kg

762,9

Carbon dioxide, biogenic

kg

7,9

Ammonium chloride

g

5,6

Water

kg

697,2

Acetic acid

g

18,7

Sulfuric acid

g

68,5

Acetic acid (sodium salt)

g

249,2

Lactic acid

g

31,0

Butanedioc acid

g

25,0

Glycerol

g

4,9

Sodium hydroxide

g

0,1

Others organic compounds

kg

0,7

Input from Technosphere

Chemicals

inorganic,

at

CHU

plant/

Output to Technosphere Material

Wastes to treatment

Output to Environment

321


Table 3. LCA characterization results (per functional unit) for the impact categories Impact Category Unit SE DA

Abiotic depletion

kg Sbeq

2,4E-03

2,1E-03

Acidification

kg SO2eq

3,3E-03

2,0E-03

5,7E-04

5,2E-04

PO43-eq

Eutrophication

kg

Global warming (GWP100)

kg CO2eq

3,8E-01

3,5E-01

Ozone layer depletion (ODP)

kg CFC-11 eq 3,3E-08

2,7E-08

Human toxicity

kg 1,4-DB eq

1,5E-01

1,5E-01

Fresh water aquatic ecotoxicity

kg 1,4-DB eq

8,3E-02

8,5E-02

Marine aquatic ecotoxicity

kg 1,4-DB eq

1,8E+02

1,8E+02


kg 1,4-DB eq

2,6E-03

2,7E-03

Photochemical oxidation

kg C2H4eq

1,6E-04

1,1E-04

Source: Method: CML 2 baseline 2000 V2.05/World, 1995 SE: Solvent extraction pretreatment DA: Dilute acid pretreatment

Table 4. Energy Ratio for the production of 1 kg bioethanol for each pretreatment under study. Study with Eucalyptus Study with Eucalyptus cultivation from Gonzálezcultivation from Ecoinvent García et al. database inventory (2012b)inventory Reference SE

DA

SE

DA

Eucalytuscultivation (MJ)

1,6

4,7

42

42

Transport (MJ)

2,6

2,6

2,6

2,6

Process (MJ)

0

0

0

0

Output

29,2 39

29,2

39

Energy Ratio (MJ/MJ)

6,9

0,7

0,9

Pretreament Input

5,3

Table 5. Global Inventory for Eucalyptus cultivation (per kg feedstock) in Ecoinvent Database Material Unit Value

Input from Environment Carbon dioxide Occupation, forest Transformation, from forest Transformation, to forest

kg

2,832

2

ma

0,518

2

0,026

2

0,026

m m

322


Wood, hard, standing

m3

0,002

Energy, calorific value, in biomass

MJ

41,96

Figure Captions Figure 1. Eucalyptus globulus composition (%dry weight)

Figure 2. Flow sheet from the bioethanol production process with Solvent Extraction pretreatment (SE).

Figure 3. Flow sheet from the bioethanol production process with Dilute Acid Hydrolysis pretreatment (DA). Figure 4. LCA characterization for the impact categories in bioethanol production for each pretreatment under study.

Figure 5. Contributions to Global Warming (a) and Acidification (b) in the production of 1 kg bioethanol

Figure 6. Contributions to Abiotic Depletion (a), Eutrophication (b), Ozone Layer Depletion (c), Human Toxicity (d), Fresh Water Aquatic Ecotoxicity (e), Marine Aquatic Ecotoxicity (f), Terrestrial Ecotoxicity (g), Photochemical Oxidation (h) in the production of 1 kg bioethanol.

Acetyl. 3.48%

Acid soluble lignin. 3.39%

Extractives. 2.37%

Protein. 1.08% Ash. 0.20%

Uronic acid. 5.02% Glucan. 45.29% Lignin. 22.40%

Xylan. 16.24%

Arabinan. 0.53%

Fig 1.

323


Fig 2.

Fig 3.

100 90 80 70 %

60 50 40 30 20 10 0 AD

A

E

GWP

Solvent Extraction pretreatment

OD

HT

FE

ME

TE

PO

Impacts categories

Dilute acid hydrolysis

Fig 4. 324


Fig 5.

Fig 6 325


LCA as a tool of Decision making process for the Environmental Improvement of wastewater treatment in Latin American and the Caribbean: the case of activated sludge technology F. Hernández-Padilla*, P. Güereca, A. Noyola. Instituto de Ingeniería – Universidad Nacional Autónoma de México Circuito Escolar s/n, Ciudad Universitaria, México, D.F., C.P. 04510, México.

+52 55 56233600 ext. 1658 [email protected] URL: http://www.iingen.unam.mx

Abstract Purpose. Technology selection of wastewater treatment must take into account not only aspects related to the investment and operating costs, but also the environmental impacts arising from the operation of the wastewater treatment plant (WWTP). For this evaluation, the Life Cycle Assessment (LCA) has proven to be a scientifically robust tool. Therefore, thisstudy presents as one of its objectives to identify the environmental impacts of wastewater treatment technologies representative of Latin America and the Caribbean (LAC) through the LCA and suggests improvement alternatives. Methods. The LCA developed in thestudy determines the environmental impacts of the nine scenarios representative wastewater treatment LAC, which were identified according to the statistical analysis of the information obtained from 2734 WWTP‘s in LAC, in this paper only three scenarios corresponding to Aeration extended and Conventional Activated Sludge are exposed. Results. The life cycle inventory (LCI) of the 3 scenarios analyzed (small, medium and large), considered 26 compounds of wastewater, electricity used, chemicals and transportation. From ICV environmental impacts were evaluated using the methodology CML2001. In this study the scenarios was arranged in three lines: water line which involvesthetreatmentof water and itsrespectiveuseofelectricity; sludge line which consider thesludge treatmentand disposal and waste line which considerthe transport ofscreeningsand emissionsin a landfillfordisposal. The LCA indicates that the water line is the one with the biggest environmental impacts in all scenarios due to electricity consumption except in Global Warming Potential andTerrestrial toxicity because the emissions involving biogas from Sludge digester(mainly of disposal sludge)and the metals content involved, on the other hand; the pretreatment has the highest participation in Ozone layer depletion category due to waste disposal. Conclusions. From the evaluation of improvements it can be concluded that is possible reduce the impacts with a utilization of biogas emissions in the sludge digester for obtain energetic and the use of biosolids to prevent the manufacture of fertilizers. Key words: Life Cycle Assessment, LCA wastewater treatment plants, technology, LCA in Latin America and Caribbean.

activated sludge

326


Introduction In the Latin America and Caribbean (LAC) region, the World Bank currently finances 63 projects in the water sector, sanitation and flood protection for a total of U.S. $ 3.900 million. The aim of these projects is to improve the quality of life, environmental conditions and public health of through the provision of sustainable services and to increase the access of water and sewer through partnerships among government, private sector and community organizations (World Bank 2010a). In theory, a sewer system and a wastewater treatment plant (WWTP), should help increasing the quality of life of a community, but how to identify whether the collateral environmental impacts of wastewater treatment systems do not derive in to limiting their benefits? This study answers this questions using life cycle assessment (LCA) methodology. There are several existing LCA studies of wastewater treatment systems for some particular cases such as Benetto et al. (2009) which develops a comparative LCA in an office building in Luxembourg; Hospido et al. (2004) and Rodriguez-Garcia et al. (2011) present studies for some regions of Europe, whilst Foley et al. (2009) study alternative wastewater systems in Australia; but the region of LAC has been poorly studied. The aim of this study is to present the first Life Cycle Assessment of representative wastewater treatment technologies in the LAC region with data of a representative sample of countries: Brazil, Chile, Colombia, Guatemala, Mexico and the Dominican Republic(established according to the reported inNoyola et al.2012). To carry out the study, the development of a reliable inventory of each scenario was necessary, its include an analysis of all the inputs and outputs per each step of process, emissions and a compile of electrical consumption, all this in each one of scenarios.The LCI obtained considers more than 26 chemical compounds emitted to air, water and soil, also raw material and energy used. Thus, the impact assessment showed the environmental performance of scenarios more representatives for region as well as to determine the main environmental loads.

Methods In order to obtain the representative configurations of WWTP for LAC data was collect by means of questionnaires applied to experts of thecountries selected each one of six countries. A sample of 2774 WWTP was treated statistically from which representative treatment technologies were identified: activated sludge, stabilization ponds, upflow anaerobic sludge blanket reactor (UASB) + thickening filter, UASB + ponds and UASB + activated sludge (Noyola et al. 2012). However in this paper only activated sludge in two variants is analyzed: extended aeration (in two flows) and conventional process. This study was done to compare the efficiency of the three different size plants, because many times the municipality must decide if to select a large plant or two or three small ones. Objective

This paper presentsthe LCA of the wastewater treatment scenarios of activated sludge technology for both the current situation in the region and improvement alternatives. This paper analyzes the environmental effect of each unit process in small, medium and large flow, the former within a range from 0.1 to 25 L s-1 , the medium from 25 to 250 L s-1 and the latter from 250 to 2500 L s-1. Description system

The three scenarios are as follows:

327


Scenario 1: Small flow, extended aeration secondary treatment coupled with drying bed. Scenario 2: Medium flow, the same considerations as for scenario 1. Scenario 3: large flow conventional activated sludge secondary treatment,mesophilic anaerobic digestion was adopted for solids stabilization and centrifugation for dewatering. Functional unit

Since the main function of a WWTP is the removal of pollutants present in sewage water in order to achieve a specific quality and, consequently, the reduction of emissions (mainly solids, organic matter and nutrients) and the protection of public health, in this work the functional unit is defined as the treatment of 1 m3 of wastewater municipal over 20 years considering one specific effluent quality and a specific biosolid quality. The effluent quality is defined as BOD (biochemical oxygen demand) of 30 mg L -1 and TSS (total suspended solids) of 30 mg L-1 according to an analysis of the discharge standards of the region. Likewise the quality of the resulting sludge is defined in accordance with the regulations for application to agricultural lands "Class B" of the United Stated EPA regulations (USEPA, 1992, 1999), because in the region only some countries have regulation and the majority these regulations are obtained from EPA. System boundaries

The LCA considered the processes during the operation phase; namely materials and energy required during the facility operation, direct atmospheric emissions, solid waste and biosolids disposal because are more representative in burdens according to Foley et al. (2009) and Vlasopoulos et al. (2006). Processes associated with the end-of-life phase and the construction phase, were ignored since they are generally negligible, when compared with the operating phases. For instance; Musharrafie (2009) concludes: the impacts amount that are in operation phase ranged from 75 to 98 percent, whilethe phasesof construction and arrangementsharefrom 25to 5%. Moreover other authors have the same observations (Emmerson et al. 1995; Zhang and Wilson 2000). In this study a representative electricity mix for LAC region, published by World Bank (2010b) is considered, which presents the use of Coal (5.9%), Gas(20.9%) and Oil(14.6%), other sources include hydro (55.8%) and nuclear (2.8%). The study considered three main kinds of data: 1) site specific operating data, 2) data from databases, and 3) data from bibliography.Hence; 1) heavy metals were obtained using data from monthly analytical results for 21 WWTP located in Mexico City elaborated by central laboratory of Water System of Mexico City (SACM, 2010, 2011),2) data from ecoinvent V2.0 database were adapted to the LAC mix, and 3) thebiogas production by the anaerobic digestion of sludge is directly related to the amount of volatile solids destroyed (VSD) ranging from 56 to 65%; hence, the gas-production rate considered is 0.8 m3 kg-1 of VSD; meanwhile, methane concentrations should be 60 to 70% (by volume) and carbon dioxide concentrations should be 30 to 35% (WEF,1999). According to data results for thisstudy, sludge disposal is made improperly, for instance; in some municipalities, sludge is send to ocean yet, in another ones is drop to sewage, also in another, sludge is disposed to uncontrolled landfill.Some large WWTP´s treat the sludge and send to landfill specific many times in the same site of the plant, and in very little cases the sludge is sent to agricultural soil.Thus in current situation, the final disposal of sludge was considered only as disposal soilwith theircorrespondingemissions according to heavy metals content 25 to 85% similar to Brown and Lester 1979; Brown et al. 1973 and Oliver and Crosgove1974 andemissions from disposal in soil according to IPCC(2006) methodology.In the same way, the produced biogas was supposed torch with 95% efficiency, in fact in almost all data from municipal plants, the biogas only is burned, no exist utilization. In this study, the CML2000 method was used to evaluatethe impact categories: Abiotic depletion (AD), Acidification (AC), Global warming (GWP100), Eutrophication (EU), Photochemical oxidation (PHO), Ozone layer depletion (ODP), Human toxicity (HT), and Terrestrial toxicity (TT).

328


Results Results for the current scenarios The secondary treatment has the highest environmental loads in DAR, AC, and HT, due to the high energy consumption in this process in all scenarios.However is possible to note in figure 1 that the scenario 3has a betterdistribution than another ones in the environmental impacts in each unit process because its energy consumption is lesser than scenario 1 and 2, this situation have two reasons:conventional process (large scenario) require more pumped air for endogenous respiration tan aeration extended process, but conventional process treat the highest flow in one similar volume of tank causing lesser HTR(the amount of time required for the wastewater to pass through ofaeration tank) so the necessary oxygen quantity per functional unit (1m3) is one-fifth of aeration extended process. In the same way, in DOE, pre-treatment has important impactbecause waste disposal (till 50% in small scenario) and the secondary treatment energy. Likewise, sludge disposal have impact the most impact in TT, due to excess heavy metals caused by finaldisposal of sludge in soil. Is important to note that in EU the pretreatment has the most impact follow for sludge disposal because in this study was considered the wastewater contaminants emissions in each unit process, so the pretreatment has the most impact in this category, but if is considered that the wastewater of pretreatment no left of system, so the sludge disposal impact will increase. These results are useful for to propose improvements to current scenarios as follow. Results for improvement proposed

Agricultural sludge destination. In the region, the adequate treatment and disposal of sludge is made only in few cases, in this study is analyzed the improvement alternative of sent sludge to agricultural soil according to USEPA (1995). Electrical production from anaerobic digestion.Although in the region is not a regular usage the electricity production from anaerobic digestion, in this study is analyzed because its valuable role in reducingimpactsbythe avoideduseofelectricity. In large scenario, the amount of biogas produced (0.079 m3CH4/m3 treated water) could be converted to 0.507 kWh/m3 of electricity, according to methane content, which helps to cover part of the plant electricity needs. As a result of improvement proposed in sludge line is possible to note in Figure2 thatDAR, AC, ODP, PHO and HThave the most important reduction of impacts, in fact,the top three return avoided impacts. EU and TT have no reduction impact cause the disposal to soilnot change with the improvements. GWP100 has no reduction in small and medium scenarios because the emissions are in disposal to soil either agricultural or only drop in soil without control, instead on; large scenario hasreduction after the improvement. Figure 3 shows the environmental performance per improve alternatives in DAR, is possible to note that the most important reduce of impact is for electrical production from anaerobic digester of large scenario.

Discussion The secondary treatment has the highest environmental impacts due to energy consuming equipment in aeration tank mainly. After the improve is possible to reduce this impacts but in real plants is necessary to analyze all costs for to realize this improve, nevertheless; is interesting toconsider the alternative of renewable forms of energy in the region. On the other hand; the sludge application to agricultureprovideenvironmental benefit (negative impacts) in AD, AC and ODP categories due to fertilizer avoided use. However; in a real plant of the region, ever is necessary to relate composition of sludge and crop performance and laboratory studies or the EPA regulations because the limits allowed for agricultural is not regulated in most of the municipalities of the LAC.

Conclusions The highest environmental impacts are in the energy consumption especially in the aeration thank, which accounts around of 60% (scenario small and medium) of the electricity consumed, 329


therefore; the recommendation also to use energy efficiently and use more renewable forms of energy, is to consider the alternative for the use of biogas, because as was showed in Figure 3 if large scenario have a cogeneration unit, theanaerobic digester can create an environmental benefit and the environmental profile of the entire scenario will be reduced. However in real plants, final decisions have to be taken considering costs of unit cogeneration and distance to agriculture soil to disposal because each plant is different and must be analyzed singly.

Acknowledgements This research is being developed with financial support of the International Development Research Center (IDRC), Ottawa, Canada and Coordinationofgraduate studiesat UNAM.

References Brown HG, Hensley CP, McKinney GL,Robinson JL (1973) Efficiency of heavy metals removal in municipal sewage treatment plants. EnvironLett 5:103-114 Brown MJ, Lester JN (1979) Metal removal in activated sludge: The role of bacterial extracellular polymers. Water Res 13:817-837 Emmerson RHC, Morse GK, Lester JN, Edge DR (1995) The life-cycle analysis of small-scale sewage treatment processes. J ChartInst Water & Environ Management 9:317-325 Benetto E, Nguyen D, Lohmann B,Schosseler P (2009) Life cycle assessment of ecological sanitation system for small-scale wastewater treatment. Sci Total Environ 407:1506-1516 Foley J, De Hass D, Hartley K,Lant P (2009) Comprehensive life cycle inventories of alternative wastewater treatment systems. Water Res 44:1654-1666 Hospido A, Moreira MT, Fernández-Couto M,Feijoo G (2004) Environmental Performance of a Municipal Wastewater Treatment Plant.Int J LCA, 9:261-271 IPCC (2006). Emissions from managed soils, and CO2 emissions from lime and urea applications. In: Eggleston, H.S., Buendia, L., Miwa, K., Ngara, T., Tanabe, K. (Eds.), 2006 IPCC Guidelines for National Greenhouse Gas Inventories, Prepared by the National Greenhouse Gas Inventories Programme. Agriculture, Forestry and Other Land Use, vol. 4. IGES, (Chapter 11), Japan. Musharrafie A (2011). Análisis de ciclo de vida ambiental y desarrollo de una metodología para la identificación y evaluación de impactos sociales mediante análisis de ciclo de vida, aplicado a dos tecnologías de tratamiento de aguas residuales en México.Dissertation, ITESM, México. Noyola A, Padilla-Rivera A, Morgan-SagastumeJM, Güereca P, Hernández-Padilla F (2012) Typology of wastewater treatment technologies in Latin America. Clean Soil Air Water 40:926932 Oliver BG, Cosgrove EG (1974) The efficiency of heavy metal removal by a conventional activated sludge treatment plant. Water Res 8:869-874 Rodriguez-Garcia G, Molinos-Senante M, Hospido A, Hernández Sancho F, Moreira MT,Feijoo G (2011) Environmental and economic profile of six typologies of wastewater treatment plants. Water Res 45:5997-6010 SACM (2010, 2011) Resultados analíticos mensuales de la calidad del agua en el influente y efluente de las PTAR del Sistema de Aguas de la Ciudad de México. Sistema de Aguas de la Ciudad de México (Monthly analytical results of water quality in the influent and effluent of the WWTP Water System of Mexico City. Water System of Mexico City), México. USEPA (1999) Control of Pathogens and Vector Attraction in Sewage Sludge. US Environmental Protection Agency.http://water.epa.gov/scitech/wastetech/biosolids/503pe_index.cfm Accessed 26 June 2011 USEPA (1992) Sewage Sludge Regulations 40 CFR Rule 503. US Environmental Protection Agency, http://water.epa.gov/scitech/wastetech/biosolids/503pe_index.cfm.Accessed 26 June 2011 USEPA (1995) Process Design Manual: Land Application of Sewage Sludge and Domestic Septage. EPA/625/R-95/001 edition, US Environmental Protection Agencyhttp://water.epa.gov/scitech/wastetech/biosolids/503pe_index.cfm.Accessed 26 June 2011 Vlasopoulos N, Memon FA, Butler D, Murphy R (2008) Life cycle assessment of wastewater treatment technologies treating petroleum process waters. Sci Total Environ 367:58-70 Water Environment Federation (1999) Chapter 22. In: Design of Municipal Wastewater Treatment Plants. WEF Manual of Practice No. 8, McGraw-Hill Prof (ed), 4th edn. USA World Bank (2010a) The World Bank and the water supply and sanitation in Latin America and 330


the Caribbean, http://go.worldbank.org/H10WS468Z0.Accessed 1 may 2010 World Bank (2010b) World Development indicators 2010, http://data.worldbank.org/sites/default/files/wdi-final.pdf. Accessed 10 July 2011 Zhang Z, Wilson F (2000) Life-cycle assessment of a sewage-treatment plant in South-East Asia. J Chart Inst Water Environ Manag 14:51-56

Figure 1 Comparison of environmental impact for unit process for the three scenarios

331


Figure 2 Comparison of the environmental impact of the sludge treatment for the current situation and alternatives

AD 0,00015 0,0001

kg CO2 eq

0,00005 0 -0,00005 -0,0001 -0,00015 -0,0002 -0,00025

LARGE. Current situation LARGE. Agriculture only LARGE. Electricity production only LARGE. Agriculture and Electricity production

Figure 3 Influence of agriculture use and electricity production in Abiotic Depletion 332


Life cycle assessment of solid biofuel production from microalgae with CO2 fixation in cement plants Codina, María Florencia – Gobbi, María Florencia – Pérez Hurtado, Cynthia Gabriela – Barón, Jorge Horacio Proyecto a-oil, Facultad de Ingeniería, Universidad Nacional de Cuyo, Centro Universitario, 5505, Mendoza, Argentina

Teléfono: ++54 261 4135000 ext 2100 [email protected],

[email protected],

[email protected],

[email protected] URL: http://www.algae-oil.com.ar

Abstract Microalgae need sunlight and carbon dioxide (CO 2) supply for their photosynthetic activity. CO2 can be obtained from flue gases that industries generate as a production waste. Cement plants produce large amounts of CO2 and consume fossil fuels accordingly. Thus, the production of solid biofuel from microalgae culturein a cement plant not only enables mitigation of CO2 in their flue gases, but also allows the reuse ofthe biofuelas an alternative energy source for the plant. Previous experiences carried out at laboratory conditions in Mendoza, Argentina have shown potentially high productivity of algal cultures.The objective of this work is to evaluate the reduction of impacts produced by the introduction of a microalgae culture in the productive process of a cement plant. Incremental impacts are analyzed by considering only the processes referred to microalgae culture. A life cycle assessment methodology of analysis was adopted. The SimaPro 7.3.2 software, ecoinvent v2 database and extrapolations from laboratory reports were used. Results show that the process under study presents an overall favorable environmental impact, especially for the impact categories of climate change and renewable energies. The negative impacts are caused mainly by the use of fertilizers (necessary to achieve good productivity of algal biomass). However, such effects are not very significant (in magnitude) when normalized. The results of this analysis are a first approximation of the efficiency of the process.It has allowed to assessing which stages of the process cause potentiallymajor impacts, both positive and negative. Thisinformation is the basis for further analysis in future studies, in which more variables not taken into account in this instance can be incorporated. Thereby, it is possible to generate tools for optimizing and achievingthe commercial applicability of the process. Key words: microalgae, biofuels, CO2 fixation, cement plants, life cycle assessment

Introduction Microalgae are photosynthetic organisms, they turnsun light, carbon dioxide (CO 2) and nutrients from the medium into biomass, just as terrestrial plants. However, the potential efficiency of microalgae is significantly higher than the one of traditional crop plants, both in terms of productivity of biomass and CO2 fixation capacity (Chisti 2007; Contreras et al. 2003). Due to this fact, CO2 mitigation by microalgae is being studied all over the world (Campbell et al. 2009; Stepan et al. 2002; J. R. Benemann 1997; Sheehan et al. 1998). Particularly, cement plants are interesting for this type of analysis because they generate important emissions of CO2, representing near of 5% of global antropogenic CO 2(Deja et al. 2010; Huntzinger & Eatmon 2009), and consume large amounts of energy (Schneider et al. 2011; Barker et al. 2009). 333


A typical cement production process starts with the mining and crushing of limestone. Next, limestone is ground and homogenized along with other minor components, forming what is known as raw meal. The raw meal is led into a first heating phase, initiating the processes of dehydration and decarbonation. Then the material enters into a rotary furnace, where temperature close to 1500°C is achieved. The high energy consumption of the process is due to this stage, in which the most important chemical reactions take place. The result of this process is mainly clinker for cement base material and CO2. Finally, the clinker is cooled and led to the cement mill, where it is mixed with gypsum and different mineral components. The resulting product of this joint grinding is cement. Approximately 60% of CO2 released during cement production is formed during the chemical transformation of calcium carbonate into carbon dioxide and lime. The remaining 40% comes from the combustion oflarge amounts of fossil fuels to obtain theenergy required by the reaction (Deja et al. 2010). Therefore, the integration of a microalgae culture process into existing cement plants can be an effective tool to solve two major environmental problems: emissions of greenhouse gases and energy dependence on fossil fuels. Consequently, microalgae would reuse a production waste, which is harmful to the environment (CO2),and produce biomass as a way to store energy (solar energy is transformed into chemical energy through the photosynthetic process). Around the world, this process is at research and developement stage (Kumar et al. 2010; Campbell et al. 2009; Chisti 2007; Stepan et al. 2002; J. R. Benemann 1997), and as far as the author‘s present knowledge, it has not been commercially exploited yet. Previous experiences carried out in laboratory conditions in Mendoza, Argentina, have shown that a potential high productivity of microalgae cultures is feasible(Da Silva et al. 2012; García, da Silva, Ávila Maniero & Barón 2011; García, da Silva, Ávila Maniero, Fonollá, et al. 2011; da Silva, García, J. H. Fuentes Berazategui, et al. 2009; da Silva, García, J. N. Fuentes Berazategui, et al. 2009). In the present work, the life cycle assessment methodology (LCA)is applied to a microalgae farm, thatuses CO2 and heat from flue gases produced by a typical cement plant, which in turn generates biomass. This analysis will provide an overview of the process on an untested industrial scale. The results obtained are useful as basis for further studies oriented to optimize the complete process and achieve its commercial use.

Microalgae productive process in cement plants Raceway ponds To incorporate a microalgae farm into a cement plant, raceway ponds can be used (Figure 1). A raceway pond is made of a closed loop recirculation channel that is typically about 0.3 m deep, in which the culture medium circulates(Chisti 2007). Mixing and circulation are produced by a paddlewheel, and flow is guided around bends by baffles. Mixing is necessary for avoiding sedimentation, providing appropriate nutrient distribution and uniform exposure of cells to sunlight. The walls and floor of the raceway pond are painted white to improve lighting conditions. Fertilizers are utilized to achieve the optimal growth conditions, depending on the quality of the medium water. According to the scale of biomass production, these systems can be built with different materials, such as concrete or compacted earth, and waterproofed with geomembrane. CO2 dilution The flue gases of the cement plants are utilized as a CO2 source to improve photosynthesis. These gases (with a CO2 content from 12% to 15% and a temperature close to 400°C) are retrieved, filtered, cooled and CO2 is diluted in the aqueous medium that flows to the culture pond. The diluted CO2 is used for the biomass production. Biomass harvest The harvest stage is critical for the feasibility of the microalgae production process because a large amount of energy is required for separating the biomass from de aqueous medium (Sander & Murthy 2010; Campbell et al. 2009; Oilgae 2009; Li et al. 2008). In this work, a tangential filtering process followed by a drying one is considered. From the tangential filtering a microalgae 334


concentrate is separated from water, that is reused in the ponds. The concentrated biomass is dried by a spray dryer that uses heat from flue gases. In this way, the residual energy released during the gas cooling is utilized, thus reducing the energy required for the drying process.The dried biomass is used for combustion in the rotary furnace.

Life cycle analysis Several software based tools exist in order to realize life cycle analyses. From these, Sima Pro software, created by PRé Consultants, was chosen, because it is useful to facilitate the analysis and the graphical representation of complex cycles in a systematic and transparent mode, following the recommendations cited in ISO 14040 rule (PRé Consultants n.d.). This software has available the Ecoinvent database, which is considered as the most complete in the market. For this work, a free academic license was obtained of SimaPro 7.3.3. The methodology to carry out the life cycle analysis according to ISO rules (ISO series 14040) comprises the following steps (Guineé 2002): A. Scope Definition

Analysis Purpose The work objective was to analyze the environmental impacts reduction that can be achieved by the inclusion on an existing cement plant an algae-based productive system to capture CO2 and to obtain biomass as a solid fuel for the cement plant. With the results from this analysis, the critical steps of the process under study were identified before it is practically implemented, with the purpose of generating decision tools for its optimization and large-scale application. The present work is, therefore, a descriptive analysis of a process which has not been yet implemented at an industrial scale. Its sophistication level is simplified as the final objective is to establish a first approach on the potential impacts of the activity under study, that then will be used for future studies (it is taken into account the fact that Life Cycle Analysis is an iterative technique, and therefore a first simplified version can then be enhanced in future studies). Functional Unit The functional unit considered in the present analysis is 100MJ of thermal energy that come from the burning of dry biomass in the cement plant furnace. Study function: use of energy in the furnace. Functional Unit: 100MJ of thermal energy in the furnace. Reference Flow: by assuming a Calorific Power of 2982kcal/kg (García, Da Silva, Ávila Maniero, Fonollá, et al. 2011) or 12485 MJ/ton, 8 kg of dry biomass are needed in order to obtain 100MJ. System Limits The processes considered in the analysis are those referred to the production of biomass and its combustion in the rotary furnace of the cement plant, as a replacement for natural gas, including the electric and fertilizer consumption in a productive operation regime. The processes which are inherent to the cement plant operation are not considered, as the objective of the study is to evaluate the incremental impact on an existing cement plant. At this instance those impacts related to the construction and dismantling of the facilities were also not included, as the long life of the facilities (20 years) implies that they are minor and not relevant for the overall impact of the functional unit. The replenishment of evaporated water was also neglected. Impact evaluation method and impact categories under consideration Within SimaPro software library different impact evaluation methods exist. IMPACT 2002+ was chosen, as it encompasses advantages of two different methodological lines (Jolliet et al. 2003) that are described as follows: Classic impact analysis(Guineé 2002): In this kind of analysis the indicator for each impact category is the immediate result of classifying the ambient loads in impact categories which are characterized by a reference substance. 335


Damage or Effect analysis method (Eco-Indicator 99 method): This kind of method classifies the obtained results in the characterization of damages or effects such as affectations on human health, to the ecosystem, or resources exhaustion. The IMPACT 2002+ method, besides complementing the advantages of the two mentioned criteria, is the synthesis of several previous methods and renowned prestigious institutions (IPCC Intergovernmental panel on Climate Change, EPA Environment Protection Agency). The impact categories, the category indicators and the characterization models are internationally accepted, that means, either based on international agreements or approved by a competent international organization (García Oca 2011). The impact categories considered in this analysis are:  Human toxicity (carcinogens + non-carcinogens): The human toxicity represents all the effects on human health with the exception of the respiratory effects caused by inorganic materials, effects of the ionizing radiation, ozone layer thinning and photo-chemical oxidation. This impact category comes from the estimation of toxicological risk and the potential impacts associated with the release of each kg of substance to the environment. 

Respiratory Organics: represents the risk on the respiratory health caused by organic particles released into the air.



Respiratory Inorganics: represents the risk on the respiratory health caused by inorganic particles released into the air.



Ionizing radiation: Is the result of the radioactive radiation.



Ozone layer depletion: Are the effects caused for the increase of UV radiation as the result of the emission of substances (NO, CFC) that contribute to the detriment of the stratospheric ozone.



Aquatic and Terrestrial Ecotoxicity: Is the result of the problems related to the emission of toxic substances to air, water and soil.



Climate warming: Represents the damage caused by the emission of winter house effect gases.



Land use: The impact that consider the use of land are measured through Transformation and Occupation (Lindeijer et al. 2002; Frischknecht et al. 2000). Transformation takes into account the change of status of the land before and after the activity, and it is measured in m2. Occupation is related to the area and also to the time required for the production of a certain amount of product, and it is measured in m2a (square meters times time).



Water and land acidification: Is the modification from the natural chemical equilibrium of the environment due to an increase on the concentration of acid elements.



Aquatic Eutrophication: Is the excessive enrichment of the water bodies with nutrients and the biological adverse effects which are associated to it.



Mineral extraction: It represents the extra effort that future generations will carry out in order to extract the remaining resources. At present, human kind extracts the best resources, leaving the less quality resources for future generations. This extra effort is expressed as ―exceeding energy‖ and it is measured as the exceeding energy per kg of iron, as a result of a reduction on the iron mines.



Non-renewable energy: Represents the total primary energy extracted, calculated from the PCI per unit. 336


Necessary data quality El productive process under study has not been taken into practice yet, and therefore there is not real data availability for all the process stages. Due to this fact, extrapolation of data obtained at laboratory scale tests was used to quantify incomes and outcomes in each subprocess. These data have been obtained during the period 2010-2011 in Mendoza, Argentina. The Ecoinvent v2 database, available with the SimaPro license was also used, and the electric mix corresponding to Argentina was adapted (Secretaría de Energía de la Nación Argentina 2009). B. Life Cycle inventory (LCI)

Data and calculation procedures were defined for quantifying inputs and outputs referred to raw material consumption, energy and land use (see Table 1). Studied process Microalgae production process was extrapolated to an industrial scale (10ha), from the following laboratory data: during a culture of 5 days with a depth of 0.15m a biomass concentration of 3.9g/L in the medium was achieved(Da Silva et al. 2012; García, da Silva, Ávila Maniero & Barón 2011). Assuming a linear growth rate, a productivity of117g/m2day is obtained. The studied process includes the following stages (Figure 2): 1. Culture: The biomass production is carried out in raceway ponds, using flue gas as a source of CO2 (by water dilution) and nutrientsupply for optimal growth: 0.07ton of Nitrogen per ton of dried biomass and 0.005ton of Phosphorus per ton of dried biomass (Oilgae 2009). For the reference flow (8kg of dried biomass), 0.047kg of Phosphoric acid (85%P in weight) and 1.2174kg of Urea (46%N in weight) are needed. CO 2 absorption is assumed as 1.83kgCO2 per kg of dried biomass (Chisti 2007) so 14.64kgCO2are needed for the reference flow. Land use is considered only for the culture stage. Land cover classes, based on CORINE land cover classes (Frischknecht et al. 2000), available at the Ecoinvent database, were used. For estimating land transformation, the total production of 10ha over 20 years of lifetime (with a productivity of 117g/m 2day) was considered, and the land associated to the reference flow was calculated as 0.0171m2 from the sclerophyllous class (CORINE 232, similar to Cuyo ecosystem) to the artificial water bodies class (CORINE 512). For land occupation,the artificial water bodies class was also utilized, and 0.3419m2a was calculated for the reference flow. Referring to the electric consumption, the paddlewheel, the CO2 injection and the water pumping systems were considered.

337


2.

Filtering: To achieve biomass concentrations of 3.4 g/L at the input and 117g/L at the output of the tangential filter the electric consumption of the filter was considered (see Table 1). Since water is recycled, its consumption is neglected, along with evaporation loss.

3.

Drying: Only electric consumption from the Spray drier is considered.

4.

Combustion: For the reference flow 100MJ of thermal energy are released (functional unit). This available energy allows the saving of 100MJ of natural gas, which is then considered as avoided product. Due to the biomass burnt, 14.64kgCO 2 are released to the atmosphere (the same quantity captured during culture stage).

C. Life Cycle Impact Assessment (LCIA)

SimaPro software was utilized to perform the LCIA with data from the LCI. To visualize the results the following analysis groups were created:  Culture: Includes all inputs and outputs of the culture stage without the fertilizers. 

Fertilizer N: Includes the urea consumption (Nitrogen source) at culture stage.



Fertilizer P: Includes the phosphoric acid consumption (Phosphorous source) at the culture stage.



Filtering: Includes electric consumptions at the filtering stage.



Drying: Includes electric consumptions at the drying stage.



Combustion: Includes the biomass combustion and the replacement of natural gas.

D. Interpretation

Impact assessment Percentage impacts of each impact category are shown in Figure 3. Negative percentages indicate a favorable impact, mainly due to natural gas substitution in combustion stage. An important favorable impact can be seen for the global warming categorygiven by the culture stage (when CO2 fixation is performed). Although the combustion stage releases CO 2 again, the fossil fuel replacement allows a favorable balance. There is an unfavorable impact associated to the combustion stage in global warming category. This is due to the difference between CO 2 emitted by the biomass combustion and the one avoided by the replacement of natural gas. The process stages with the most unfavorable impact are those related with fertilizer use. Urea utilization as a Nitrogen source is the main cause of impact in most categories,except Non-carcinogens and Aquatic Eutrophization, where the use of phosphoric acid has a major contribution. The electric energy consumption does not seem to cause big impacts, except for Ionizing Radiation and Mineral Extraction categories. Table 2 shows impact values for each category, and the contribution by analysis group. Impact assessment. Normalization Normalization allows the analysis of the contribution of each impact to the total damage, applying normalization factors. For the utilized method (IMPACT 2002+), the normalization factors are given by the ratio of the impact per unit of emission divided by the total impact of all substances of the specific category, per person per year (Jolliet et al. 2003). Figure 4 shows that the most important impacts for the analyzed process are those referred to Climate change and Non renewable energy, both favorable. Unfavorable impacts of other categories seem to have a low contribution. Results of normalization are shown in Table 3. 338


Conclusions In the present work, the life cycle assessment methodology was applied to a microalgae farm, that uses CO2 and heat from flue gases produced by a typical cement plant, which in turn generates biomass. The results of the analysis show that, under the current assumptions (lineal extrapolation of the laboratory scale to a productive scale) the process presents a favorable environmental impact, specially for Climate change and Non renewable energy categories. There are negative impacts caused mainly by the use of fertilizers (necessary to achieve a good biomass productivity). However, such impacts are not very significant when compared with the favorable CO 2 emission balance. In light of the results of the present analysis, it seems feasible to apply this process as a strategy to mitigate the effects of climate change. Moreover, the unfavorable impacts of drying stage are minimized by the use of residual heat from flue gases. However, it is important to emphasize that the energy performance and productivities assumed in this analysis were taken from experiences in laboratory conditions and they may differ from those achieved in an operative scale. The use of fertilizers may be a potential improvement for minimizing harmful effects on the environment. Further improvements could be achieved by the use of urban wastewater as a culture medium to reduce the use of fertilizers. The results of this analysis are a first approximation of the efficiency of the process from the environmental point of view. Stages with major impacts, both favorable and unfavorable, have been detected. This serves as a basis for further studies incorporating more variables not taken into account in this instance. In this way, it is possible to optimize the complete process and achieve its commercial use.

Acknowledgements The authors would like to thank Prof. Mst. Ing. Irma Mercante, from National University of Cuyo, for her collaboration with the realization of this work.

References Barker, D.J. et al., 2009.CO2 Capture in the Cement Industry.Energy Procedia, 1, pp.87–94. Benemann, J.R., 1997. CO2 mitigation with microalgae systems.Energy Conversion and Management, 38, pp.S457–S479. Campbell, P.K. et al., 2009. Greenhouse Gas Sequestration by Algae: Energy and Greenhouse Gas Life Cycle Studies, CSIRO Energy Transformed Flagship. Chisti, Y., 2007. Biodiesel from microalgae.Biotechnology Advances, 25(3), pp.294–306. Contreras, J.M.P.., Flores, L.B. & Cañizares, R.O., 2003. Avances en el Diseño Conceptual de Fotobiorreactores para el cultivo de microalgas. Interciencia, 8(8), pp.450–456. Deja, J., Uliasz-Bochenczyk, A. & Mokrzycki, E., 2010. CO2 emissions from Polish cement industry. International Journal of Greenhouse Gas Control, 4, pp.583–588. Frischknecht, R. et al., 2000. Code of Practice.CD-ROM Final report ecoinvent, (2). Available at: http://www.ecoinvent.org/fileadmin/documents/en/02_CodeOfPractice.pdf [Accessed November 2, 2012]. García, C.B., Da Silva, S.M., Ávila Maniero, M., Fonollá, M.A., et al., 2011. Cultivo de consorcios microalgales autóctonos como fuente alternativa de energía: caso de estudio. In XVIII Simposio Nacional de Bioprocesos SINAFERM. Caxias do Sul/RS. García, C.B., Da Silva, S.M., Ávila Maniero, M. & Barón, J.H., 2011. Cultivo de consorcios microalgales autóctonos como fuente alternativa para la producción de combustibles de tercera 339


generación. In VI EnIDI 2011 Encuentro de Investigadores y Docentes de Ingeniería. Sesión de Doctorandos. Los Reyunos, San Rafael, Mendoza, Argentina: UTN-FRM. García Oca, L., 2011. Análisis de Ciclo de Vida en la aplicación intensiva de energías renovables en el ciclo de agua, España: Aguas de Barcelona. Guineé, J.B., 2002. Handbook on Life Cycle Assessment: Operational Guide to the ISO Standards, New York: Springer. Huntzinger, D.N. & Eatmon, T.D., 2009. A life-cycle assessment of Portland cement manufacturing: comparing the traditional process with alternative technologies. Journal of Cleaner Production, 17(7), pp.668–675. Jolliet, O. et al., 2003. IMPACT 2002+: A new life cycle impact assessment methodology. The International Journal of Life Cycle Assessment, 8(6), pp.324–330. Kumar, A. et al., 2010. Enhanced CO2 fixation and biofuel production via microalgae: recent developments and future directions. Trends in Biotechnology, 28(7), pp.371–380. Li, Y. et al., 2008. Articles: Biocatalysts and biorreactor design - Biofuels from Microalgae. Biotechnol. Prog., 24, pp.815–820. Lindeijer, E. et al., 2002. Improving and testing a land use methodology for LCA, including case studies on bricks, concrete and wood. Rijkswaterstaat-DWW report. Oilgae, 2009.Oilgae Report Academic Edition, Available at: www.oilgae.com. PRé

Consultants,

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http://www.pre-

sustainability.com/simapro-lca-software [Accessed November 14, 2012]. Sander, K. & Murthy, G.S., 2010.Life cycle analysis of algae biodiesel.The International Journal of Life Cycle Assessment, 15(7), pp.704–714. Schneider, M. et al., 2011. Sustainable cement production–present and future.Cement and Concrete Research, 41, pp.642–650. Secretaría

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http://energia3.mecon.gov.ar/contenidos/. Sheehan, J. et al., 1998. A look back at the US Department of Energy‘s Aquatic Species Program: Biodiesel from algae, National Renewable Energy Laboratory. Da Silva, S.M., García, C.B., Fuentes Berazategui, J.H., et al., 2009. Cultivo de consorcios microalgales autóctonos como fuente alternativa para la producción de combustibles de tercera generación. In V EnIDI 2009 Encuentro de Investigadores y Docentes de Ingeniería. Sesión de Doctorandos. Los Reyunos, San Rafael, Mendoza, Argentina: UTN-FRM. Da Silva, S.M., García, C.B., Fuentes Berazategui, J.N., et al., 2009. Cultivo de microalgas autóctonas a escala de laboratorio para producción de aceites y obtención de biocombustibles. In 2do Congreso Latinoamericano de Refinación. Mendoza: Instituto Argentino del Petróleo y del Gas IAPG. Da Silva, S.M. et al., 2012. Microalgas autóctonas: una alternativa a la generación de biocombustibles en la región de Cuyo, Mendoza, Argentina. In CLABA 2012 Tercer Congreso Latinoamericano de Biotecnología Algal. Chile: Universidad de Concepción. Stepan, D.J. et al., 2002. Carbon dioxide sequestering using microalgal systems US Department of Energy Report., 2002-EERC-02-03. 340


Figures Figure 1. Flow diagram of the microalgae production process in a cement plant Existing cement plant

Microalgae farm

Bag filter

Raw meal

Flue gases

Microalgae concentrate

Tangential filtering

Diluted culture

Heat exchange tower

Permeated water Ashes Drying

CO2 dilution

Dried biomass Rotary furnace

Clinker

CO2

Dried biomass Raceway ponds Fuel

Figure 2. Block diagram of the studied process

Figure 3. Impact Assessment – Characterization.Method: IMPACT 2002+V2.06/IMPACT 2002+. Excluding infrastructure processes. 100 80 60 40

%

20 0 -20 -40 -60 -80 Carcinog ens

Non-carc inogens

Respirat ory inorg

Ionizing radiatio

Ozone la Respirat Aquatic Terrestri Terrestri Land occ Aquatic Aquatic Global w yer deple ory orga ecotoxici al ecotox al acid/n upation acidifica eutrophi arming Culture Fertilizer N Fertilizer P Filtering Drying Combustion

Non-rene wable en

Mineral extractio

Analyzing 1 p 'COMBUSTION'; Method: IMPACT 2002+ V2.06 / IMPACT 2002+ / Characterization / Excluding infrastructure processes

341


Figure 4. Impact Assessment – Normalization. Method: IMPACT 2002+V2.06/IMPACT 2002+. Excluding infrastructure processes. (Units: person.year)

1.2e-3 1e-3 8e-4 6e-4 4e-4 2e-4 5.42e-20 -2e-4 -4e-4 -6e-4 -8e-4 -1e-3 -1.2e-3 -1.4e-3 Carcinog ens

Non-carc inogens

Respirat ory inorg

Ionizing radiatio

Ozone la Respirat Aquatic Terrestri Terrestri Land occ Aquatic Aquatic Global w yer deple ory orga ecotoxici al ecotox al acid/n upation acidifica eutrophi arming Culture Fertilizer N Fertilizer P Filtering Drying Combustion

Non-rene wable en

Mineral extractio

Analyzing 1 p 'COMBUSTION'; Method: IMPACT 2002+ V2.06 / IMPACT 2002+ / Normalization / Excluding infrastructure processes

342


Tables Table 1. Inputs and outputs for 100MJ of thermal energy from microalgae biomass Stage

Inputs

Outputs

Culture

Electric power: Phosphoric acid: Urea: Flue gas CO2: Recycling water:

0.8916 0.0471 1.2174 14.64 2017

kWh kg kg kg L

Land use: transformation fromshrub land, sclerophyllous (CORINE 0.0171 232); to artificial water bodies (CORINE 512)

m

Land use: (CORINE 512)

0.3419

ma

occupation

2051

L

34.2

L

2017 8

L kg

2

2

Filtering

Electric power:

1.8297

kWh

Drying

Diluted culture: Electric power: Concentrated culture:

2051 0.7070 34.2

L kWh L

8

kg

Combustion Dried biomass:

Diluted culture:

Concentrated culture: Recycling water: Dried biomass:

Thermal energy (natural gas 100 replacement)

MJ

CO2 emission:

kg

14.64

Table 2. Impact assessment – Characterization. Method: Método IMPACT 2002+ V2.06 / IMPACT 2002+. Excluding infrastructure process. Impact category

Units

Total

Culture

Fert. N

Fert. P

Filering

Drying

Comb.

Global warming Ozone layer depletion Aquatic eutrophication Land occupation

kg CO2 eq

-1.45E+00

-1.42E+01

3.54E+00

5.64E-02

9.33E-01

3.60E-01

7.85E+00

kg CFC-11 eq

-1.41E-07

7.01E-08

6.08E-07

5.38E-09

1.44E-07

5.56E-08

-1.02E-06

kg PO4 P-lim

8.26E-04

6.11E-07

1.62E-04

6.92E-04

1.25E-06

4.85E-07

-3.04E-05

m2org.arable

5.12E-05

1.92E-06

9.99E-05

1.23E-05

3.93E-06

1.52E-06

-6.84E-05

Mineral extraction Respiratory inorganics Respiratory organics Non-carcinogens Aquatic acidification Terrestrial acid/nutri Carcinogens Terrestrial ecotoxicity Aquatic ecotoxicity Non-renewable energy Ionizing radiation

MJ surplus

1.11E-04

1.99E-05

4.37E-05

7.68E-06

4.09E-05

1.58E-05

-1.69E-05

kg PM2.5 eq

2.45E-03

8.14E-05

2.75E-03

1.60E-04

1.67E-04

6.45E-05

-7.71E-04

kg C2H4 eq

-5.18E-05

8.54E-05

8.32E-04

1.33E-05

1.75E-04

6.77E-05

-1.23E-03

kg C2H3Cl eq

1.36E-02

1.28E-04

4.83E-03

9.15E-03

2.63E-04

1.02E-04

-8.78E-04

kg SO2 eq

1.19E-02

5.10E-04

1.39E-02

1.53E-03

1.05E-03

4.04E-04

-5.48E-03

kg SO2 eq

7.59E-02

2.87E-03

8.73E-02

2.27E-03

5.88E-03

2.27E-03

-2.48E-02

kg C2H3Cl eq

-8.60E-03

4.12E-03

3.65E-02

1.11E-03

8.46E-03

3.27E-03

-6.21E-02

kg TEG soil

1.09E+01

2.46E-01

1.02E+01

2.65E-01

5.04E-01

1.95E-01

-4.92E-01

kg TEG water

3.12E+01

3.01E+00

1.99E+01

2.81E+00

6.17E+00

2.38E+00

-3.02E+00

MJ primary

-1.54E+01

9.72E+00

7.71E+01

8.01E-01

1.99E+01

7.70E+00

-1.31E+02

Bq C-14 eq

4.82E+01

1.04E+01

1.32E+01

1.54E+00

2.13E+01

8.23E+00

-6.40E+00

343


Table 3. Impact Assessment – Normalization. Method: IMPACT 2002+V2.06/IMPACT 2002+. Excluding infrastructure processes. (Units: person.year) Impact category

Total

Culture

Fert. N

Fert. P

Filtering

Drying

Comb.

Global warming

-1.46E-04

-1.43E-03

3.57E-04

5.70E-06

9.42E-05

3.64E-05

7.93E-04

Ozone layer depletion

-2.08E-08

1.04E-08

9.00E-08

7.96E-10

2.13E-08

8.23E-09

-1.52E-07

Aquatic eutrophication

-

-

-

-

-

-

-

Land occupation

4.07E-09

1.52E-10

7.95E-09

9.79E-10

3.13E-10

1.21E-10

-5.44E-09

Mineral extraction

7.31E-10

1.31E-10

2.87E-10

5.06E-11

2.69E-10

1.04E-10

-1.11E-10

Respiratory inorganics

2.42E-04

8.03E-06

2.72E-04

1.58E-05

1.65E-05

6.37E-06

-7.61E-05

Respiratory organics

-1.55E-08

2.56E-08

2.50E-07

3.98E-09

5.26E-08

2.03E-08

-3.68E-07

Non-carcinogens

5.37E-06

5.06E-08

1.91E-06

3.61E-06

1.04E-07

4.01E-08

-3.47E-07

Aquatic acidification

-

-

-

-

-

-

-

Terrestrial acid/nutri

5.76E-06

2.18E-07

6.63E-06

1.72E-07

4.47E-07

1.73E-07

-1.88E-06

Carcinogens

-3.40E-06

1.63E-06

1.44E-05

4.40E-07

3.34E-06

1.29E-06

-2.45E-05


6.28E-06

1.42E-07

5.87E-06

1.53E-07

2.91E-07

1.12E-07

-2.84E-07

Aquatic ecotoxicity

1.14E-07

1.10E-08

7.29E-08

1.03E-08

2.26E-08

8.74E-09

-1.11E-08

Non-renewable energy

-1.01E-04

6.39E-05

5.07E-04

5.27E-06

1.31E-04

5.07E-05

-8.59E-04

Ionizing radiation

1.43E-06

3.07E-07

3.91E-07

4.57E-08

6.31E-07

2.44E-07

-1.90E-07

344


Life Cycle of a School Power Station with Combined Renewable Fuels - Avoided CO2 Emissions Estimated with CDM *

*

Labriola, Carlos V. M. - Palavecino, Alejandro – Ferraris, Isabel

*

*Universidad Nacional del Comahue, Facultad de Ingeniería, Centro de Estudios de FER. Buenos aires 1400 (8300) Neuquén.

++54 2994481262 [email protected]

Abstract A School Power Station with combined renewable fuels (CEECRC) isbeing installed in the Faculty of Engineering, National University of Comahue (UNCo). It will cover up to 75% of UNCo´s demand and 90% of annual energy. The energy is obtained by means of the following Renewable Energy Sources (FER)  Wind Energy: Two Darrieus-Troposkien vertical axis wind turbines have been designed. It will produce 5kW and 50kW respectively.  Micro-Hydro: A Turgo turbine of 3 to 5 kW is available, with 15 to 20m of Head height between two reservoirs.  Biodiesel: A process with microalgae is being developed to obtain lipids and then with esterification process, biodiesel will be obtained.  Biogas: Digesters using organic matter from the University dining hall will be used to feed anaerobic bacteria produced in FIUNCo to obtain Biogas by means of an anaerobic digestion process. Purpose: The objective of this work is the analysis of the avoided CO2 emissions during the Life Cycle of CEECRC Methodology: The Methodology is based on Clean Development Mechanism (CDM) of United Nations (UN) and the emission factors are adopted fromthe Secretary of Energy of Argentina. The total installed power in UNCo will be 1.165 MW. The Unit Commitment of the generators will be adjusted to 75% of the power required by total demand of UNCo every hour. This restriction is taken into account because there is no Energy Contract 345


with the Utility Service Company to offer them the surplus energy. In addition there are no laws in Argentina to regulate this kind of transaction. Results: The results of total avoided CO2emissions are obtained from the gross avoided CO2 emissions minus the total CO2 emissions during the Life Cycle of CEECRC. The CO2 avoided emissions are 97% compared with CO2 Emissions during the Life Cycle of the power station. Conclusions: The study of CO2 emissions (avoided or not) during the Life Cycle is very relevant in any Energy Generation Development. It is very important not only because ofthe economic profit calculation but also for the cost of ambient and human health impact. Avoided CO2 emissions are converted in terms of forestry area to fix CO2 and in a period of time of generation to compensate the energy use by CEECRC during Life Cycle. Key words: Power, Station, School, CO2, Life Cycle, Renewable Energy, Sources

1- Introduction The concept of School Power Station in Faculty of Engineering of UNCo (FIUNCo), was born during 1980 decade. The idea was taken from the Energy Electric Institute (EEI) of Federal University of Mexico. The Mexican power station of 40MW used boilers of special design for Mexican oil with sulphur. Actually, there are several Renewable Energy Sources in Comahue Region and different Power Station and Energy Services Utility Companies which produce, transmit or distribute electrical energy from traditional energy resources (natural gas and big hydro). These companies are assisted by other ones that give installation, maintenance and spare parts services. All these companies need qualified workers for training whose need to maintain their position or new one. Since 2003 several actors of society in Argentina began to be conscious about the benefits of using Renewable Energy Sources and Hydrogen vector. This situation appears when non renewable fuels begin to scarce in the local Argentine market. Also local Universities began to include in their academia and research works, topics related with renewable energy sources to obtain thermal and electrical energy. Since 2002, subjects related to Renewable Energy and Environment in the FIUNCowere included in the curriculaof all engineering careers (Labriola, C., 2002). In this way the Sustainable Energy Group (GES) of FIUNCo began to offer training to Energy Companies, and lecturers started teaching in Universities and High School. The concept to offer training and services of Renewable Energy Sources with the CEECRC installation startedin 2010 by means of Research Project FAIN 4/160: "School Power Station by means of combined Renewable Fuels" (Labriola, C., 2010) (Palavecino, A., 2012), and then in June 2011 with the creation of the Renewable Energy Sources Analysis Centre (CEAFER) in the FIUNCo Institution (CEAFER, 2011). This project is related to the application of renewable energy sources as Wind, Solar, MicroHydro, Biomass available in Comahue Region of Argentina. CEAFER brings engineering and research services on these renewable sources including Ocean Energy to Companies and other academic institutions (UNPA, 2010). Also there is a place where renewable energy converters are tested. Consolidated Research Groups (GIAC) work in CEAFER. They came from Electrical (1 group) and Mechanics (2 groups) departments which develop projects related on intermediate technology and advanced applications (Labriola, C., et al, WEFF, 2012).

2- Proposal The electrical demand of the UNCo was estimated in 1,5MW by means of demand power and energy analysis. This electrical charge is shared on different points of Low Voltage (LV) connections to the Utility Service Company (CALF). The implementation of the CEECRC not only offers LV interconnection but also Medium Voltage of 13,2kV (MV) by means of transformers. MV connection brings the benefit of low tariff on power and energy to UNCo. 346


Taking into account the demand analysis and CEECRC installation, this work is related to Avoided CO2 net emissions of this power station, using renewable energy fuels. The renewable energy sources available in UNCo to obtain electrical energy are Wind, Solar, Biomass and Micro-Hydro (Labriola, C., et al, CLADE, 2012). The GIACs which works in CEAFER and CEECRC project are: Wind Engineering Group (GIV) and Hydraulic Machines Laboratory (LAMHI) from Mechanical Engineering Department and Sustainable Energy Group from Electrical Engineering Department. The converters available for renewable energy sources are:  Wind: GIV and GES have made a study of this resource in the FIUNCo determining an annual average wind speed of 5 m / s with a dominant direction of west-southwest and density of about 1.2 kg/m3, (Palese, et, al, 2012).  Micro-Hydro: LAMHI developed a Turgo turbine from 3 to 5 kW with a head height of about 15m for use with free flow and confined.  Solar: Solar energy is 4.5 kWh/m2 in winter and 7.5 kWh/m2 in summer, but in the latter period UNCo is in summer holidays.  Biomass: GES has studied the different types and qualities of biomass generated in the UNCo. The main source of biomass is the dining hall and common rooms of different faculties. In the case of biodiesel, there is a novel research group studying the process to obtain lipids from microalgae.

3 - Methodology The calculation methodology is based on the Kyoto Protocol which sets three flexible mechanisms, whose main objective is to offer those interested in reducing emissions, ways to reduce them at lower cost. These mechanisms are: Emissions Trading, Joint Implementation and the Clean Development Mechanism (CDM). In the case of small-scale projects different categories were established as shown in Table 1: TABLE 1

CATEGORIES FOR SMALL SCALE PROJECTS Category I.A.Residential generation

Technology electricity

Renewable Energy Sources used for residential user.

I.B. Mechanical energy for users/companies

Renewable energy generation to supply mechanical energy for users and companies which need a little energy amount: mechanical, thermal or electrical one.

I.C. Thermal Energy for end user.

Thermal renewable energy supply replacing non renewable fossil or biomass (should no exceed 45 MW)

I.D. Electricity Generation with renewable sources to supply distribution grid

Renewable energy i)installations which supply electricity a distribution grid with at least one power station with fossil fuel, or non renewable biomass. (limits: eligible Renewable Powerof 15MW – Cogeneration based on Biomass less than 45MWt)

We can conclude from Table 1 that the project may be included in Category IA small-scale CDM and will follow the methodology of the Panel on Climate Change of the United Nations, (approved Small Scale Methodologies) Version 14 (PCCde the UN, AMS, 2010). The baseline is determined by the fuel consumption of the technology used for energy generation. Once determined the baseline year values of each fuel through energy consumption, emissions are calculated by multiplying them by the CO2 emission factor of displaced fuel. An emission factor is a ratio between the quantity of pollutant emitted into the atmosphere and the power of the unit in operation. The emission factor (EF) provides the amount in tones of CO 2 equivalent that are achieved by reducing or avoiding each MWh generated, and it is the basis for the reduction of emissions of greenhouse gases (GHG) produced by the application of energy efficiency, renewable 347


energy or cogeneration projects, which impact on the generation of electricity. Emission reductions are obtained from the factor emissions based on two coefficients which areOperating Margin (OM: it includes all plants that are in operation last year) and Build Margin (BM: it includes plants that have been installed in the last 3 years). Besides the methodology provides two alternatives for calculating the combined margin (CM) which are: 1-For solar and wind projects, it must take values WOM = 0.75 and WBM = 0.25, giving more weight to the operating margin. 2-For the rest of these projects, it should have a value of WOM = 0.5 and WBM = 0.5. W: indicates a proportion of OM and BM to obtain RE. EF:values as shown in the latter paragraph can be seen in Table 2 for 2011. Ex Ante calculation is made by means of average value of generation of the last three years and Ex post calculation is made by means of average value of generation of the year that this work consider, which is 2011. TABLE 2 EMISSIONS FACTORS USING COMBINED MARGIN (CM)

EMISSION FACTORS

CM COMBINED WITH 0,5 BM

CM CON 0,25 BM Y 0,75 OM

AND 0,5 OM (T CO2/MWH)

(T CO2/MWH)

CM EX POST

0,478

0,509

CM EX ANTE

0,478

0,508

It can be seen that most of the installed generation in the Argentine electricity system is thermal and at the same time, large hydro and no new power stations entered into the system in recent years. This makes the CM EX post and CM EX ante are virtually identical. The Unit commitmentand energy supply by the different available RES in UNCoare shown in Table 3. TABLE 3 UNIT COMMINTMENT DEPENDING DIFFERENT RENEWABLE ENERGY SUPPLY AND STARTING YEAR OPERATION

Power, Energy and RES PeakDemand (kW) PeakPowersupply (kW) Micro-Hydro EnergySupply Wind (kWh/year) Biogas Biodiesel Energy purchased to CLAF (kW/year) TOTAL

Year 1 400 295 43.800 402.998 397.902 177.563

Year 2 600 535 43.800 435.030 847.963 222.751

Year 3 1000 875 43.800 1.165.700 1.065.598 335.817

Year 4 1350 1165 43.800 1.567.909 1.444.164 469.169

29.962

28.795

19.651

26.221 3.525.042

The baseline avoided emissions (ELB) for different RES in operation for EF with maximum and minimum values, can be seen in Table 4.

348


TABLA E 4 BASELINE AVOIDED EMISSIONS FOR DIFFERENT RES OF CEECRC

of RESULTS Año 1 Mín. Max. 20,94 22,29 Micro Hydro 192,44 205,12 Wind 190,00 190,22 Biogas 84,79 84,89 Biodiesel AvoidedEmissio n 488,17 502,53 (t CO2) Kind Renewable Energy Fuel

Año 2 Min. 20,94 207,73 404,91 106,37

Max. 22,29 221,43 405,38 106,49

739,95 755,59

Año 3 Min. 20,94 556,64 508,84 160,36 1246,7 7

Max. 22,29 593,34 509,43 160,54 1285,60

Año 4 Min. 20,94 748,70 689,61 224,03 1683,2 8

Max. 22,29 798,06 690,41 224,29 1735,05

The first 4 years of operation are shown in Table 4. It can be seen the increase of t CO2 avoided being emitted by fossil fuels. Furthermore it can be seen the increase of the avoided CO2 avoided emissions following the unit commitment of different RES in UNCo reaching the maximum installed capacity of 1,165 MW in the fourth year. For this study, it is considered the best condition, represented by the highest values in the right column of Table 4. In the case of CO2 emissions for Design, Manufacture, Installation, Maintenance Operation, Dismantling and Recycling of parts periods,the report ofVestas Company is used. This report shows the calculation of emissions through Energy Balance Method in those periods based on the ISO 14040/14041/14042/14043. The values of CO2 emitted of CEECRC, were obtained by calculation of energy consumed for the needs of each period by the worst EF of Argentine electricity system (SEA) and the results are shown in Table 5. TABLE 5 CO2 EMISSIONS ESTIMATION DURING THE LIFE CYCLE OF CEECRC

EnergyDemandMWh Period

Design Manufacturing MaintenanceduringOperation Dismantling Recycling of Parts TOTAL

520,00 1356,65 333,77 591,92 -196,98

Emission Factor (Worst of SEA) 0,509 0,509 0,509 0,509 0,509

t CO2 emited

264,68 690,53 169,89 265,65 -95,17 1295,58

4 - Results Table 6 shows the total emissions avoided during an operation of 25 years, total life cycle emissions and the result of total net emissions in the life cycle. Emissions are also expressed in percentages. The operation period of 25 years is considered because is the normal operation period of any electromechanical device for industrial and generation application. TABLE 6 FINAL VALUES OF CO2 AVOIDED EMISSIONS BY CEECRC

Total CO2avoided in 25 years of operation 44873,05 100%

Total CO2 emissions during Life Cycle 1295,58 3%

CO2 net emissions during life Cycle of CEECRC 43577,46 97%

349


5- Conclusions The final value of Table 6 is the net value of avoided CO2 emissions throughout the Life Cycle of the CEECRC. It should be noted that for the periods before and after the operation, an estimation of emission values was madeand it is not an exact calculation of them. In percentage terms it can be seen that CO2 emissions are very low for CEECRC (3%) for avoided emissions, making it very appropriate to be installed in areas with access to different renewable sources. Another way to look at the emissions life cycle CEECRC is estimating the time needed for generation with renewable energy to offset emissions from the use of non-renewable energy in that cycle. In other words the CEECRC should generate 4.4 months to offset emissions throughout the life cycle. This value is calculated by dividing the generation of energy used in the life cycle over annual generation for CEECRC at full power. To get an idea of the magnitude of the avoided emissions from the use of oil as fuel, we can compare with afforestation necessary to fix the CO2 emitted by oil. This comparison was made for year 4 with thermal generation using gas and diesel generator sets compatible electricity with renewable fuels proposed. Table 7 shows the results. TABLE 7 CO2 COMPARISON DURING OPERATION WITH FORESTRY (POPLAR FIX 39,88T CO2/HA .YEAR)

0,505

Totalgeneratio t CO2 n / year (Year 4) 1735,0 5 3.525.042,4 1780,1

0,648

2284,2

EnergySource

EF (t CO2/MWh)

Generationwith CEECRC Generation 100% Nat. gas Generation 100% Gasoil

Severalrenewablecombinedfu els

Ha of Popla r 43,5 44,64 57,28

It can be seen that using hydrocarbons they need more equivalents Ha of poplar to fix CO2 with afforestation than equivalent area of renewable fuels. By means of the results of the evaluation with CDM methodology, it permits to access to Green Bond issue by CO2 avoided. But the minimum economical power module to this proposal is about 10MW. Therefore this project aims the integration with others in the region and make together a proposal completing Green Bonds for 10MW or more (COPIME 2012). For the optimization of this project, given its multidisciplinary and interdisciplinarycondition, it is necessary a holistic approach in the management process throughout the life cycle of the CEECRC (Ferraris, I. et al, 2010).

References CEAFER, 2011: creation of Renewable Energy Sources Analysis Centre, Faculty of Engineering, UNCo, Chief manager: Labriola, C.,june 2011, Expte.2873/00-29/09/11. COPIME, 2012: ―Congreso de Ingeniería para el Cambio Climático‖ Presentation of Green Bons, September, 19-20,2012. 350


IEE - México, 1980s: ―Project of SteamScool Power Station of 40MW‖ Electrical Energy Institute, Federal University of Mexico, 1980-1990. Labriola, C. 2002: Lecture: ―RenewableEnergy and ttheEnvironment‖, Lecturer: Labriola C., createdon 2002, FIUNCo. Labriola, C., 2010: Research Project FAIN 4/160: ―Central Eléctrica Escuela a partir de Recursos Renovables Combinados‖. G.E.S, FIUNCo. Director: Labriola, C. Co-Director: Pérez, R.. Period 1/2010 a 12/2013. Labriola, C., et al, CLADE, 2012: ―Design and implementation of CEECRC withintelligentgridonLow Voltaje‖, LatinoamericanElectricityDistributionCongress, Rosario, Santa fé, September, 24-26, 2012. Labriola, C., et. al. WEEF, 2012: ―Academia Units of UNCo using electricity by means of Renewable Energy Sources‖ World Engineering Education Forum, October, 21-14, 2012. Palavecino, A., 2012: PostgraduateThesis: ―Estudio del CO2 evitado por la Central Eléctrica Escuela de la FIUNCo‖, 2009-2012, FIUNCo. Director: MSc. Labriola, C. Palese, C, et al, 2012: ―Modelado a Microescala de variables eólicas para banco de ensayos eólicos en Neuquén‖, LatinoamericanCongress of WindEngineering (CLIV), La Plata, Province of Buenos Aires, December, 5-7, 2012. P.C.C.de la N.U., AMS, 2010: ―Aproved Small Scale Metodologies, Indicative simplified baseline and monitoring methodologies for selected small-scale CDM project activity categories‖. Versión 14, 2010. UNPA, 2010: ―Wave and Marine current test building project‖, Director: labriola, C., National University of Austral Patagonia, Caleta Olivia Academic Unit, Santa Cruz, March, 2010. Vestas , 2005: ―Life CycleAssesment‖, para turbinas de 3MW, empresa Vestas, 23-03-2005. Ferraris, I., et. al, 2010: ―Análisis de Riesgo aplicado a Proyectos de Enseñanza de la Ingeniería‖IICAIM, Co-Author: Labriola, C., San Juan November 7-10, 2010.

351


Life Cycle Assessment of Brazilian Biodiesel Sandra Maria da Luz* – Armando Caldeira-Pires – Frederico Sampaio Vasconcelos Vilela – Thiago Oliveira Rodrigues *Faculty of Gama – University of Brasília, Área Especial de Indústria Projeção A, Setor Leste, Gama, 72444240, Brasília - DF, Brazil.

[email protected] http://www.fga.unb.br

Abstract Nowadays renewable fuels have been received a crescent attention because the potential environmental improvements. In Brazil, there are specific regulations about the use of ethanol and biodiesel as biofuel in vehicles, becoming compulsory the biodiesel use since 2008. Biodiesel is defined as the monoalkyl esters of fatty acids derived from vegetable oils or animal fats. In simple terms, biodiesel is a product of a transesterification chemical reaction using an alcohol and oil, resulting glycerin as co-product. In Brazil, there are some industrial units that have been producing biodiesel, and depending on the oil type, different pretreatments were employed to impurities and acid removal from raw material. Then, there are two different process, chemical for soybean oil and physical, for palm oil. The objectives of this work were to characterize the environmental impact for the cradle-to-gate life cycle assessment for 1kg of biodiesel obtained by different pretreatment process. Life cycle inventory considered chemicals, fertilizers and auxiliary process in the oil production, complete primary data about refine oil and transesterification process and transportation of raw materials (chemicals, catalyzer and oil) to biodiesel factory. Considering the pretreatments for three main impacts categories, the physical treatment presented the worst environmental performance, with values two times bigger than chemical treatment. Keywords: Biodiesel, LCA, cradle-to-gate.

Introduction There are numerous environmental problems caused by the intensive use of fossil fuels (e.g., carbon dioxide [CO2] emissions, pollution and resource depletion), which highlights the disadvantages of an unbalanced ratio of resource demands. The growing interest in alternative renewable resources, such as CO2-neutralizing materials, suggests that biomass derived from agricultural products is an important source of raw materials for various products and biofuels [1]. Regarding biomass use, life-cycle assessment (LCA) can be applied to determine environmental impacts of the production of a product, such as soybean oil, while simultaneously integrating various environmental impact categories into the assessment. Biodiesel has been established as a successful fuel in the Brazilian energy matrix. Biodiesel can be 352


produced from a wide variety of oleaginous plants, such as soybean, cotton, babassu and palm oil. Several aspects of soybean oil and palm oil production will be discussed below, and a description of biodiesel production via oil treatment and transesterification will be presented, as well a comparative evaluation of the environmental impacts along the biodiesel life-cycle. The life cycle scenario considered the agricultural and industrial phase. In this work the industrial phase was more discussed considering particular aspects as treatment type, physical or chemical, depending on the oil type.

Methods Life cycle assessments used as an analytical tool and modeling biodiesel production is facilitated in Gabi 5.0 software. Characterization of environmental impacts is based on CML 2001 method (Dec 2009). The flows of inputs and outputs in the process was based on in the mix of secondary (agricultural phase), primary (industrial phase) data and database from ELCD and Gabi. Functional unit

This study mainly dealt with the overall sustainability of biodiesel obtained from different kind of oil. Depending on the oil, a different pretreatment process is applied to refine it. This cradle-togate assessment allowed to choice the best process, considering environmental aspects. This analysis considered 1 kg of biodiesel at the gate of the industry. System boundaries

The system analyzed included the complete life cycle from the extraction of raw materials and agricultural practices up to the industry gate. Figure 1 shows the system boundaries for the industrial stage of biodiesel production. The agricultural stages associated with palm and soybean oil were based on secondary data.

Figure 1. Major steps involved in the industrial phase of biodiesel production.

Inventory Life Cycle

Soybean Oil In Brazil, soybeans are intended to be consumed ―in natura‖ or processed, in the form of soybean 353


meal (used in the manufacture of animal feed) and soybean oil (used in food or in the production of biodiesel). Brazil is the second-largest soybean producer in the world, producing approximately 67 million tons on 25 million ha, with a productivity of 2,665 kg/ha [2]. The life cycle inventory for soybean considered agrochemicals (herbicides, pesticides, fertilizers and phosphate) and soil and by the processes involved in their production. Palm Oil An analysis of the inputs and outputs related to the agricultural phase of 1 ha of oil palm production over the complete crop cycle of 30 years shows that the most important inputs in terms of mass are water and fertilizers, followed by diesel. Despite the culture involves mostly manual operations, there is high diesel consumption by the activities adjacent to the farm, such as the transport of inputs. Although it does not yet represent a large share of biodiesel production (contributing approximately 0.25%), the palm oil, or dendê (Elaeisguineensis), shows great potential, especially in the northern region of Brazil [3]. The average yield of crude palm oil ranges from 3 to 6 tons per ha, compared to the soybean yield of 0.2 to 0.6 tons per ha [4]. Some additional benefits of oil palm are that it is a perennial crop and is well adapted to the edaphoclimatic conditions of the Amazon region. The Biodiesel Production Biodiesel plants usually operate units for oil treatment and transesterification. The operation of these plants is directly related to market demand and maintenance and operation conditions, in addition to crude and refined oil prices. With a current biodiesel yield, of approximately 270 m3/day, the processing units of the plant are essentially those that carry out pretreatment, transesterification, steam generation and the storage and distribution of products, residues and byproducts. The plants receive a greater amount of refined oil than degummed oil; the latter consists of a mixture of raw materials (vegetable oils, animal fats and residual oils and fats) that are usually derived from soybean, tallow, oil palm, residual fat oil and cotton. Oil Pretreatment Unit The type of pretreatment stage is determined by the acidity and the amount of phosphorus specific to the oil to be refined. When using soybean as raw material, it is necessary to conduct chemical treatment due to their high phosphorus content and high acidity. However, physical treatment is sufficient to decrease the acidity indexof oil palm (20 ppm phosphorus). At the end of refine, the oil should present a maximum acidity index of 0.1%. Pretreatments are performed individually for each type of oil; if the oils are mixed, this occurs before transesterification and after the individual treatments. Soybean oil, in particular, should be treated with phosphoric acid and caustic soda to remove phosphatides and free fatty acids. After the reaction is complete, the fluid passes through a 354


centrifugation step to remove soaps and other residual products. During the pretreatment step, coproducts such as fatty acid and gum are produced. All of these coproducts are marketed or used for specific applications. Transesterification Unit Transesterification is a chemical process involving a catalyst-assisted reaction between methanol and oil for the purpose of obtaining biodiesel. In the plant, the mixture of the methanol, catalyst and oil is performed in the production line. Transesterification generally involves more than one step, and each step has a residence time of 20 min. The resulting product is overflowed to a separation tank, where glycerin (30%) diluted in methanol (30%); water and salt are separated from the biodiesel. The biodiesel is neutralized with HCl to achieve a pH in the range of 5 to 7 to deactivate the catalyst (which was not separated in the previous step). The biodiesel is then washed to remove excess nonpolar compounds (methanol and NaCl). This process continues for 20 min, and the biodiesel attains a pH between 5.5 and 6. The same washing process is performed for the glycerin. The excess methanol added to the process is recovered and reused, as is the biodiesel wash-water. Glycerin containing 10% water and 0.1% methanol is recovered after transesterification and also marketed.

Results and Discussion The entire life cycle assessments for 1kg of palm oil and soybean biodiesel is showed below. Figure 2 presents the primary energy consumption and Figure 3 displays the Global warming potential - GWP for both cycles.

Primary energy consumption (relative contribution %)

100 90 80 70 60 50 40 30 20 10 0 Palm oil (agricultural phase)

Palm oil biodiesel (industrial phase)

Soybean oil (agricultural phase)

Soybean oil biodiesel (industrial phase)

Figure 2. Primary energy consumption (MJ) in each process for soybean and palm oil biodiesel production.

The Figure 2 shows the primary energy consumption for both biodiesel processes. The energy 355


encompasses fuel, electricity and steam used in this process. The biodiesel production spends the most part of energy in the life cycle. Due to the fact that the high energy consumption in this

Global warming potential - 100 years (relative contribution %)

phase. By the time, the palm oil, in agricultural phase spends more energy than soybean oil.

80 70 60 50 40 30 20 10 0 Palm oil (Agricultural phase)

Palm oil biodiesel (Industrial phase)

Soybean oil (Agricultural phase)

Soybean oil (Industrial phase)

Figure 3. Global warming potential (CO 2 equiv.) for each process for soybean and palm oil biodiesel production.

The palm oil shows the important result about agricultural phase. During this phase, the CO 2 emission is higher than in another process. That is why in the agricultural phase, there are the intense use of fertilizers and another inputs like polyethylene bags, for example. Considering only the industrial phase the results are grouped in Figure 4. The results showed that the palm oil pretreatment is responsible for the higher emission of CO 2 in respect to soybean oil biodiesel. The only difference between this biodiesel processes is the pretreatment, physical or chemical. About 41% of industrial phase emissions for palm oil biodiesel are due to physical

Global warming potential 100 years (relative contribution %)

process, otherwise for soybean only 3 % is due to the chemical pretreatment.

120 100 80 60 40 20 0 Palm oil biodiesel (physical pretreatment)

Soybean oil biodiesel (chemical pretreatment)

Figure 4. Global warming potential considering only industrial phase.

356


Conclusions It can be concluded that the GHG associated with the production of biodiesel is dependent on the different unit processes encompassed by the transformation of vegetal oil. Moreover, the definitions of which processes will be used rely on the origin of the vegetal oil and its quality. Moreover, there must be a greater effort to improve agricultural management practices to decrease the consumption of fuel, fertilizers and herbicides. For biofuel-based systems, the impacts associated with fossil fuel consumption for agricultural transport and practices, as well as those related to fertilizer and pesticide production. Regarding vegetal oil processing for biofuel production soybean biodiesel is associated with higher values compared with oil palm biodiesel in all of analyzed categories, mainly due to extra unit processes needed to prepare the vegetal oil to be transesterified. These results depicted the importance of the vegetal oil pretreatment processes, pointing out the need of comparative studies that analyze optimized vegetal oil storage and transport, as well that analyze the influence of fertilization practices on oil phosphorus content.

Acknowledgments We would like to thank the financial support provided to authors by Petrobras and CNPq.

References 1.

Gielen, D.J.; Fujino, J.; Hashimoto, S.; Moriguchi, Y. Biomass strategies for climate

policies? ClimatePolicy2002, 2, 319-333. 2.

CONAB - Companhia Nacional de Abastecimento [NationalSupplyCompany].

Acompanhamento da Safra Brasileira: grãos, oitavo levantamento, maio 2012 [MonitoringofBrazilianharvest: grains, eighthsurvey, May 2012] Acompanhamento da Safra Brasileira: grãos, oitavo levantamento, maio 2012 [MonitoringofBrazilianharvest: grains, eighthsurvey, May 2012] 631.165(05), C743b. 2012. 3

Organização BNDES e CGEE. Bioetanol de cana-de-açúcar: Energia para o

desenvolvimento sustentável [Bioethanolfromsugarcane: Energy for sustainabledevelopment]; BNDES: Rio de Janeiro, 2008. 4.

Xavier, J.H. Análise de ciclo de vida (ACV) da produção agrícola familiar em Unaí-MG:

resultados econômicos e impactos ambientais [Life CycleAnalysis (LCA) offamilyagriculturalproduction in Unai, Minas Gerais: economicresultsandenvironmentalimpacts] Dissertação Mestrado – Universidade de Brasília, Centro de Desenvolvimento Sustentável. 2003. 5.

ANP – Agência Nacional de Petróleo [NationalAgencyofPetroleum]. Boletim Mensal de

Biodiesel http://www.anp.gov.br/?pg=60127&m=&t1=&t2=&t3=&t4=&ar=&ps=&cachebust=13367451967 14. 6.

NAE Cadernos NAE – Biocombustíveis [Biofuels]; NAE: Brasília, DF, 2005. 357


Multi-Step Decision Making on Life Cycle Assessment Methods for Industrial Sectors Robert Ilg * – Hannes Krieg * *Dept. Life Cycle Engineering (GaBi) University of Stuttgart, Chair of Building Physics Wankelstrasse 5, 70563 Stuttgart-Vaihingen

Phone

+49-(0)711-970 3174

Fax

+49-(0)711-970 3190

[email protected]

Abstract A way to quantify environmental impacts of a product is to conduct a Life Cycle Assessment (LCA). For this purpose the impacts can be determined from two different perspectives. The economically oriented top-down approach which determines the environmental effects approximately by considering the monetary in- and output flows of the economy. It is called the input-output based LCA (IO-LCA). The alternative bottom-up approach reconstructs all steps in the life cycle of a product and determines the resulting environmental effects in detail. In contrast to the IO-LCA, this approach is referred to as process-based LCA (P-LCA). A systematic multi-step approach was developed to compare environmental accounting methods and support the corporate decision making of a company. To make sure all relevant criteria are involved in the review and comparison, a set of criteria was created. The selection of the criteria was based on a detailed analysis of the considered LCA-methods, literature reviews and analysis of similar studies. Thus, eight main criteria categories are identified, each divided into subcriteria. The presentation deals with the structured analysis and comparison between the ecological accounting methods in a systematically way and can support the decision process within a company. Keywords: Life Cycle Assessment, Input-Output Analysis, Multi-Step Approach, LCA in Aviation

Introduction The starting point of this study was the discussion in the aviation industry on which method should be used for the determination of product-related environmental impacts. The aim of this study is therefore to support the aviation sectors decision with the development of a systematic approach. For this purpose, the available range of environmental accounting methods was determined. Identified as suitable methods were the top-down oriented input-output-based Life Cycle Assessment (LCA) and the bottom-up oriented process-based LCA. Based on this analysis, the significant aspects for this decision were determined, grouped and transformed into a set of criteria. To link the required objectivity of the decision to the individual requirements of users, the selection process was divided into two parts: the objective method evaluation and the criteria weighting. As part of the method evaluation, the two accounting alternatives for each criterion were compared and rated. The situational requirements and conditions have been integrated into the decision making process through the weighting of the eight main criteria. The assessments were calculated separately then brought together and evaluated. For a practical review of the results obtained, both methods were applied and compared by assessing an Airbus A320-200 358


vertical tail. With the analysis of the criteria weighting which was filled by three departments at EADS, it was demonstrated that the situational requirements, arising from the different activities of the areas considered, influence the subjective relevance of the criteria and thus the selection of method. However, within the scope of the study it was shown that in addition to the separate evaluation of each area of activity through a coherent view, the synergy and learning effects must be included in the final decision. Finally, the practical application of both methods performed on an A320-200 vertical tail has shown that the individual emissions considered in the context of input-output based LCA can be used as adequate estimation for two of the four regarded environmental impacts. The comparison also confirmed the previous assessment of the two methods and the values derived from the decision matrices results.

Background Accounting of environmental impacts for product systems

A way to quantify environmental impacts of a product is to conduct a Life Cycle Assessment (LCA). For this purpose the impacts can be determined from two different perspectives. The economically oriented top-down approach which determines the environmental effects approximately by considering the monetary in- and output flows of the economy. It is called the input-output-based LCA (IO-LCA). The alternative bottom-up approach reconstructs all steps in the life cycle of a product and determines the resulting environmental effects in detail. In contrast to the IO-LCA, this approach is referred to as process-based LCA (P-LCA). It is presumed that the input-output-based LCA (IO-LCA) and the process-based LCA (P-LCA) are well known and therefore will not be explained again specifically in this paper.

Development of an approach for the comparison of environmental accounting methods Construction of a decision-making- and evaluation-matrix

The decision problem arises from the purpose to evaluate the product-specific environmental impacts. To determine the consequences of each alternative, a multistage approach shown in Fig 1Fig 1was developed.

359


Decision problem

1.

2.

Developing a set of criteria

Evaluation of the methods (literature-based)

3.

Situational weighting of the criteria no

yes

4.

Weighted evaluation of the methods

5.

Evaluation of results

Consistency?

Decision making

Fig 1 Flowchart of the developed decision-structure (five steps)

[1] 1.

Developing a set of criteria

To make sure all relevant criteria are involved in the review and comparison, a set of criteria is created. The selection of the criteria is based on a detailed analysis of considered LCA-methods (see chapter 2), literature reviews and analysis of similar studies [2],[3]. Thus, eight main criteria are identified, each divided into sub-criteria. These criteria are shown in Table 13.

360


Main and sub criteria applied in decision A Recognition

B

C

D

A.1

General methodological recognition (expert literature, guidelines, standards)

A.2

Acceptance and application in the industry

A.3

Recognition among policy makers, NGOs and the public

Capacity B.1

An examination of the data, methodical procedure and results is provided

B.2

The method is based on scientific knowledge

B.3

The method has a high degree of objectivity

Traceability C.1

The data used can be viewed and reviewed

C.2

The calculations and assumptions are clearly documented

C.3

The basic concept of the method is easy to understand

Flexibility D.1

E

F

G

D.2

The method covers a wide range of products and environmental impacts The method cover the entire life stages of the product system

D.3

The results can be used for a wide range of applications

D.4

The method is adaptable to company-specific characteristics

D.5

The method allows the separate detection of co-products

Completeness E.1

The method enables a complete mapping of the product system

E.2

The method captures the data comprehensively and differentiated

State of the data F.1

The data used is up-to-date

F.2

The data used is representative

F.3

The required data is readily accessible

F.4

The threat of a unconscious influence of the result is low

Software G.1 There are software products available G.2 The software is readily understandable G.3 The software offers various features G.4 The software supports the user G.5 A detailed presentation of the environmental impacts is possible G.6 The method supports the presentation and export of the results

H

Time and monetary expenditure H.1

The time required for the first data collection and application of the method is low

H.2

The time required for the repeated data collection and application of the method is low

H.3

The cost of technical support is low

Table 13 Main- and sub criteria applied in decision

2.

Evaluation of the considered environmental accounting methods

The two accounting alternatives are compared and rated based on the sub-criteria. Since the criteria include quantitative and qualitative aspects, a numerical scale is required, to classify the qualitative information. For the evaluation, a scale ranging from -3 to 3 is chosen (see Fig 2). The signs (+ or -) do not constitute a positive or negative rating, but represent a preference for one of the methods.

361


Fig 2 Scale with a range from -3 to 3, to evaluate the LCA-methods The pairwise comparison indicates which of the two methods satisfies the criterion to a greater degree, relative to the other. If both methods are considered as equivalent, the value "zero" is assigned. The evaluation is based on literature research and compared to similar studies [2], [3].Fig 3shows the results of the evaluation summarized for each main criterion.

Fig 3 Result of the comparative evaluation of the two LCA methods From Fig 3 it is apparent that neither of the two methods can be classified as superior over all relevant criteria. However, it can be seen that in some areas the benefits of one method greatly outweighs. The process-based LCA for example offers a much higher flexibility (criterion D) while the input-output based LCA is particularly advantageous for the criterion time expenditure. 3.

Weighting of the criteria

Theoretical description and explanation of the criteria weighting

In addition to the objective evaluation, the situational requirements of the environment as well as the subjective perception of the decision maker have to be considered to solve a decision problem. Both variables are included on the weighting of the criteria. The weighting procedure is based on the Analytic Hierarchy Process (AHP) from Thomas Saaty. The eight main criteria are compared with each other in pairs and each pair receives a rating. Possible rating values are shown in Fig 4. A higher weight is assigned to important criteria and a lower weight to less important once.

362


Fig 4 Scale for the weighting of the criteria The pairwise comparison is performed in a matrix, shown exemplary for five criteria in Fig 5.

Fig 5 Exemplary excerpt of the matrix used for the pair-wise comparison The criteria are listed in the matrix both vertically and horizontally. The white fields above the main diagonal are filled out by the decision maker in the respective division. The fields (grey striped) below the main diagonal arise in a logical implication of the entered values (inverse value). The matrix is read from left to right. For example, if the decision maker classifies traceability (criterion C) as much more important than flexibility (criterion D), the field C/D is filled out with the value of four. The values will be aggregated for each criterion. The total values are called weighting factors. They reflect the influence of a single criterion on the overall decision. Practical implementation of the criteria weighting

In cooperation with EADS, three divisions with different requirements for an LCA are identified. The three divisions are: 

Research and Technology Management



Cabin & Cargo Engineering



Final Assembly Line

The comparison of the three matrices shows that the "capacity of the results" (Criterion B) has the greatest influence on the decision (between the LCA-methods) in all areas. Despite of the consistent assessment regarding to the most important criterion, in evaluation of all other pairwise comparisons, there are strong variations between the three divisions.

363


4.

Combination of method evaluation and criteria weighting

The evaluation carried out in step 2 has to be combined with the weighting of the criteria (see step 3) to make a final decision. This is done by multiplying the evaluation results for each subcriterion with the weighting factor of the associated main criterion. Subsequently, the individual results for each main criterion are aggregated. If there is a positive final value, the requirements are better met by the input-output based LCA. A negative sign qualifies the process-based LCA as the suitable method. Table 14shows the intermediate and final results for all three EADS divisions.

Table 14 Intermediate and final results for each of the three EADS divisions It can be seen that the process-based LCA is more suitable for the situational requirements in the two divisions‘ research and technology management as well as cabin & cargo engineering. For the final assembly department the input-output based LCA is more advantageous. 5.

Evaluation of the results

It has been shown, that  the special requirements of the divisions lead to different weights and thus to different preferences. 

according to its strengths, the process-based LCA is used in areas in which the product

system changes frequently or is being developed. 

in areas with technically and temporally narrow defined procedures, such as the final

assembly division, the input-output based LCA is preferred. 

the divisions should not be considered completely independent of each other. Since only a

coherent consideration can illustrate the synergy and learning effects associated with decisions. 

the dataset collected in earlier stages of development can reduce the cost of pro-cess-

based LCA in the following divisions significantly and minimize the advantage of the input-output based LCA.

Practical verification of the developed approach Please note, that the results will be shown at the conference and not included in this paper due to limited space and confidentiality issues.

Summary The approach developed in this study structures the comparison between the ecological accounting methods in a systematical way and supports the decision process within the aviation industry. Related to the current requirements of the considered subdivisions at EADS the process-based LCA was determined as appropriate accounting method using the developed approach. 364


Acknowledgement This paper is based on work conducted together with EADS Innovation Works (EADS IW). This contribution is highly appreciated [5].

References [1] DIN EN ISO 14040 (2006): Umweltmanagement – Ökobilanz – Grundsätze und Rahmenbedingungen [2] Reimann, K. (2011): Evaluation of environmental life cycle approaches; Dissertation (2010) TU Berlin. [3] Suh, S (2010): Handbook of Input-Output Economics in Industrial Ecology; Eco-Efficiency in Industry and Science, Jg. 23, Springer Verlag, Dordrecht (NL). [4] Grunwald, G. (Airbus) (2011a): Geometry Data Bank: Vertical Tailplane, Hrsg.: Airbus, Hamburg. [5] Bauch, K., Ilg, R. (2011): Entwicklung eines Ansatzes für den systematischen Vergleich ökologischer Bilanzierungsmethoden im Luftfahrtbereich; Masterarbeit; LBP-GaBi, Stuttgart, Germany.

365


Environmental and Socioeconomic LCA of Milk in Canada Mia Lafontaine1,*, Jean-Michel Couture2, Rosie Saad1, Julie Parent4, Manuele Margni3, Jean-Pierre Réveret4 1

Quantis Canada, 395 Laurier Ouest, Montreal, QC, H2V 2K3, Canada

2

Groupe AGECO Inc. 2014 Rue Cyrille-Duquet Bureau 307. Quebec, QC G1N 4N6, Canada

3

CIRAIG, Department of Chemical Engineering, P.O. Box 6079, ÉcolePolytechnique de Montréal, QC, H3C

3A7, Canada 4 University du Québec à Montréal, Montreal, Canada 

Corresponding author. E-mail: [email protected]

Abstract As part of its initiatives to improve the environmental performance of dairy production in Canada, the Dairy Farmers of Canada commissioned in 2010 a full environmental and socio-economic life cycle assessment (LCA) for the production of milk across Canada. This paper summarises the methodology, results and conclusions. In line with existing publications, the environmental LCA found that the main sources of greenhouse gases were emitted at the farm, with enteric fermentation, manure management and feed production. Potential impacts on ecosystem quality were mostly caused by feed production land use with some potential ecotoxicity. Potential burdens on human health were dominated by ammonia emissions. The water footprint was strongly linked to geography and the use of irrigation. To understand the impact of the choices in practices, the analysis compared regionalised provincial average results. Scenarios based on practices were modelled to understand the scale of impact reduction possible. Keywords: environmental impact, social LCA, dairy, water footprint, regionalisation

1. Introduction In an effort to clarify the path towards sustainable milk production in Canada, the Dairy Farmers of Canada, in the context of the Dairy Research Cluster, commissioned the Life Cycle Assessment (LCA) of Canadian Milk. The study took place over two years, with the support of the Canadian Dairy Farmersand collaboration of many stakeholders, including provincial associations, researchers and stakeholders in the dairy sector. The project‘s objectives were threefold: 1) To evaluate the environmental and socioeconomic impacts of dairy production in Canada; 2) To identify potential areas of focus for further improvements of the dairy sector‘s sustainability; 3) To provide the framework and the building blocks to support comparison and benchmarking.

It was innovative in different ways, mainly by its scale and regionalisation of impact, and also by integrating the first Social LCA (S-LCA) in the dairy sector. With a large inventory of farm datasets, the socioeconomic performance of dairy farmers wasassessed and the environmental impacts of their activities were calculated based on provincial average inventories, allowing for interpretation of variable farming 366


practices and their impact on overall performance, such as understanding how impacts were related to geophysical conditions.

2. Methods The current study followed ISO 14040/14044 standards, as well as the International Dairy Federation (IDF)‘s guidelines on LCA (IDF, 2010) and the UNEP/SETAC Guidelines for S-LCA (UNEP/SETAC 2009). As per the IDF‘s guidelines, the functional unit chosen was 1 kg of fat and protein corrected milk (FPCM). The boundaries of the study stopped at processing-plant front gate (farm gate + transportation). As per the guidelines, carbon sequestration in soils was excluded, and allocation between milk and meat was calculated according to a physicochemical equation, resulting in an average allocation to milk of 82%.

2.1. Life Cycle Inventory

A majority of activity data was sourced from on-farm surveys (Table 15).

Table 15.Data and their main sources Data Diet

Source percentages,

manure

Cost of Production Surveys (Ontario, Quebec, New Brunswick,

storage practices

Nova Scotia, Prince Edward Island)

Manure spreading information,

Sheppard et al. (2011) survey on 500 farms

energy Equipment and energy used in

Mail-in surveys (Alberta, Ontario)

feed production Fertiliser

types

and

Sheppard et al. (2009) NH3 emissions from fertilisers

concentrations Housing, energy & equipment in

Ecoinvent models

feed production Manure spreading tendencies

Provincial federations (most)

Crop yields, herd size, farm area

Statistics Canada

Farmers

Cost of Production Surveys (Ontario, Quebec, New Brunswick,

behaviours

towards

their stakeholders

Nova Scotia, Prince Edward Island) and Mail-in surveys (Alberta,

(S-LCA)

Ontario)

Suppliers’ behaviours (S-LCA)

Secondary data (various sources)

In total, cost of production surveys as well as mail-in surveys collected information from more than 300 farms in Alberta, Ontario, Quebec, and the Atlantic Provinces. A previous survey (Sheppard et al., 2011) supplied additional information on farm practices for all provinces. When no specific site data were available, or whenthe contribution to impact was known to be minimal, life cycle inventory databases were used, mainly ecoinvent 2.2(SCLCI, 2010). In the last resort, when assumptions were necessary because activity data were not available, expert judgements were used for validation. Models based on ecoinvent are summarised below, with adaptation described where relevant.

367


2.2. Life Cycle Inventory Assessment

On the environmental side, the global framework adopted in this study (¡Error! No se encuentra el rigen de la referencia.) is based on the peer-reviewed and internationally recognised LCIA method IMPACT 2002+ (Jolliet et al., 2003, updated by Humbert et al., 2012) with several novelties inspired by the work done for the development of IMPACT World+(CIRAIG et al., 2012), including consistent spatially explicit levels and improved impact category modelling.Eighteen impact categories are included in this study. While they can be reported and interpreted separately, they can be modelled up to the five damage indicators: Climate Change, Natural Resources, Human Health, Ecosystem Quality and Water footprint, allowing their respective contribution to be put into perspective. IMPACT 2002+ grouping methodology was used to aggregate the midpoint indicators.

Figure 13. The LCIA framework used (regionalised impact categories in bold)

2.3. Regionalisation

Nine of the 18 impact categories were regionalised (bold, Fig. 1). Having a specific geographic context, this study considers a multi-scale spatially explicit life cycle approach for both inventory and impact assessment levels. Indeed, Canada is divided into distinct regions showing differences in land covers, vegetation patterns, climate and hydrological systems, and soil types. Spatial differentiation is important when quantifying the environmental footprint at each life cycle stage of Canadian milk production for regional impacts (e.g., acidification, eutrophication, smog) and local impacts (e.g., ecotoxicity). However, potential impacts at the global level (e.g., ozone depletion, global warming) are not affected by an emission‘s location. Moreover, to perform regionalised assessment that accounts for spatial differentiation, impact indicators that address environmental problems in the agricultural sector and are highly sensitive to regional characteristics were included: water use, land use, acidification, eutrophication, toxicity and ecotoxicity. The 368


framework used in this study and the methods underlying these regional-specific impact indicators are based on the IMPACT World+ LCIA method. Provincial regionalisation was achieved using the geographical coordinates and production volumes of 13,331 farms in Canada, considering local conditions (ecoregions, watershed, etc. Characterization factors specific to farm locations were averaged by province using the annual productions of each farms. Results were calculated per province and weighted into a single environmental performance, while allowing for analysis of different practices between provinces. Activities deemed as ―background‖ (upstream of the farm) were assessed using characterization factors for the country.

2.4. The socioeconomic assessment framework The UNEP/SETAC‘s Guidelines describe the concepts and identify the main steps of implementation to conduct the S-LCA, such as the groups of stakeholders to include in an S-LCA (Workers, Local Community, Value Chain Actors and Society) and proposes a list of issues of concern to document at each stages of the life cycle. They do not however define any particular assessment methodology.A particular framework was therefrom developed to make this assessment applicable to the milk production chain. The main businesses involved in the system were identified, working from the dairy farms upstream towards their supply chains.

More specifically, a Specific Analysis was conducted over the Canadian dairy farms and their Boards. The goal of this framework was to provide a detailed analysis of the socioeconomic performance of the dairy sector by assessing the degree of social responsibility towards its stakeholders. Behaviours were documented using primary data collected through surveys completed by over 300 dairy farmers located in six provinces, as well as by the dairy Boards. More than 20 issues of concern were documented using about40 socioeconomic indicators (¡Error! No se encuentra el origen de la referencia.). The assessment of the performance was conducted using a four-tier scale (when applicable) of responsible behaviour, from risky, compliant, proactive and commited behaviour. The definintion of these scales for each indicator was established based on consultations with stakeholder groups. Data was then acquired through personal surveys to dairy farmers as well as by surveying the provincial dairy boards. Furthermore, a Potential Hotspot Analysis (PHA) was performed over the Canadian dairy sector‘s upstream suppliers. A PHA assesses the risk of encountering behaviours going against accepted social norms among the enterprises part of the system‘s supply chains, with the goal of providing a preliminary overview to point out issues for which a deeper analysis is needed. The using

PHA

was

performed

generic

data,

i.e.

available

in

data

national

and

international databases, NGOs‘ reports, websites, etc. According to data availability, the assessment was

conducted

either

at

a

Figure 2. Issues of concern documented at the farm level

business, sectorial or national level using a risk evaluation scale of Low, Moderate or High Possibility of risk of encountering hotspots at each stage of the system according to a list of social issues of concern related to the Guidelines‘ stakeholder categories. 369


3. Results The side by side environmental and socioeconomic assessment of milk was not fullyintegrated as one since this experience showed that independent, yet coherent Environmental and S-LCA frameworks are needed to fulfil each tool‘s purpose (Couture and al. 2012). For this reason, results are presented separately, while the discussion integrates both perspectives (section 4).

3.1. Environmental performance

The average footprint of 1 kg of Canadian FPCM was calculated for each province using provincial averages of inventory flows and provincial weighted averages of characterisation factors based on farm locations and their production.

Table 2. Sources of impact and allocated profile Damage Indicator

Main Contributor

Value

Unit

Climate Change

Enteric fermentation, feed production, manure

1.01

kg CO2e

Ecosystem Quality

Land use, aquatic ecotoxicity from metals in mineral

2.35

PDF.m2.yr

supplements Human Health

NH3emissions (land use), NOx, SO2 (energy & diesel)

8.3e-7

DALY

Resource Depletion

Feed production, energy on farm, transportation

3.98

MJ

Water Consumption

Irrigation (when applicable), evaporation in energy production

20

L

3.1.1. Climate change

The distribution of greenhouse gas emissions (Fig. 3) was similar to that of other studies. While energy, transportation and buildings and equipment had little impact (8% of the total), the most important emissions were caused by CH4 and N2O emissions, occurring, in decreasing order, from enteric fermentation, manure

kg CO2e / kg FPCM

storage and feed production.

0,7 0,6 0,5 0,4 0,3 0,2 0,1 0

46% 20%

CO2

27%

N2O CH4 5%

3%

Figure 3.Distribution of average greenhouse gas emissions per kg of fat-and-proteincorrected milk (FPCM) across life cycle steps, with spread of provincial average results (error bars). 370


Variability in provincial results washighest (0.025-0.17 kg CO2e/kg FPCM) for energy emissions, due to the variability of the electrical-grid-mix among provinces (14-293 g CO2e/kWh).Variability was likely underestimated in feed production, due to the assumption that fertilisation recommendations were always followed. Still, based on soils and crops, manure spreading practices varied among provinces, while emission factors also varied based on geography, a result mostly linked to humidity (Rochette et al., 2008). Feedproduction emissions were lowest in Alberta and Saskatchewan, because of their dry climate, while they were highest in British Columbia, due to a moist climate and high N recommendations for hay (200-300 kg N/ha, compared to less than 150 kg/ha elsewhere), followed by the Atlantic provinces, also because of moist climates, average yields and lower milk production per animal. Variability in emissions from livestock management were linked to changing replacement-animal ratios (since their feed, digestion and manure is also included in the milk production system), as well as digestibility of feed, with concentrates, for example, having higher digestibility than forage. Finally, different types of manure storage contributed to variability in manure-management emissions.

3.1.2. Water footprint

Water use was influenced by two distinct scenarios: irrigated crops in western Canada and non-irrigated crops elsewhere. Water withdrawal, based on low-resolution statistics, reached 550 L/kg FPCM in the worstcase scenario (highest irrigation per hectare) but was as low as 29 L/kg FPCM elsewhere. In terms of consumed water (removed from watershed through evapo(transpi)ration or incorporation in product), the this footprint ranged from 11-336 L/kg FPCM. With only 1.2% of milk produced in irrigated areas, the overall weighted average amounts to 20L/kg FPCM. The potential impacts on human health, ecosystem quality and resource depletion were assessed following different methodologies (including Maendly et al., 2010, Pfister et al., 2009,van Zelm et al., 2010,Verones et al., 2010) yet were shown to be negligible overall (< 1%). With regards to water scarcity, it is only critical in a specific location in the prairies that is not well represented in provincial averages yet still targets an important concern.

3.1.3. Ecosystem quality

In this category, potential impacts were mostly linked to land use, while the inclusion of mineral supplements in sensitivity assessments displayed a potential contribution to ecotoxicity, mainly from copper and cobalt. A small contribution to impact also exists from ammonia emission towards acidification.

Potential biodiversity loss both from land use change and ecotoxicity showed sensitivity to farm location, as a function of

geographic

variation

in

characterisation factors (CFs), such as shown in Figure 14. The effect is obvious when provincial values calculated using regional-levelCFs are compared to those calculated

using

national-level

CFs

(Fig.5). 371

Figure 14 - Map of regionalised land use characterisation factors (CFs)


3.1.4. Human health Potential effects on human health were modelled with six different impact categories, but only toxicity was regionalised. While toxicity plays a role in the overall impact(around 7%), ammonia emissions have the greatest influence(63% of potential impact). Ammonia emissions, from fertilisers, in housing and from manure storage, are linked to respiratory difficulties. The remainder of impacting substances also falls in the category of respiratory inorganics, related to fossil-fuel combustion (emissions of NOx, SO2, and hydrocarbons), electricity production and direct use. Potential toxicity impacts are also due to the heavy metal content of manure spread on crops not used in feed. Zinc, most notably, bio-accumulates, and excess zinc consumption (through crops) can interfere with the absorption of other essential minerals (ODS, 2011).

3.1.5. Hotspot assessment

Where hotspots were found, variability among provincial averages was analysed to understand the underlying trends. For climate change, the largest source of variability was the carbon footprint of energy used at the farm. This, in turn, was linked to the electrical-grid mix used ineach province(0.025-0.17 kg CO2e/kg FPCM), with provinces supplied by hydroelectricity having the smallest footprint. Next inrangeof variability was manure management and feed production. For the former, the percentage contribution of CH4 and N2O varied furthermore, where solid storage caused higher N2O emissions and liquid storage was dominated by CH4 emissions. The province with the lowest manure footprint had55% of farms usingsolid storage and tanks with a natural crust for liquid storage. Meanwhile, the province with the highest manure footprint had many liquid lagoons (37% of farms overall), driving its contribution much higher.

Table 3. Comparison of manure storage practices and their emissions (FPCM = fat-andprotein-corrected milk).

% of manure

Averaged

Solid

Solid on

Liquid

Liquid

Liquid

Liquid

Manag’t

Storage

Pasture

with

with

with No

Lagoon

Crust

Cover

Cover

Canadian

34%

13%

37%

5%

8%

3%

0.32

0.17

0.30

0.31

0.34

0.35

0.96

% CH4

47%

15%

4%

40%

52%

61%

86%

% N2 O

53%

85%

96%

60%

48%

39%

14%

avg : kg

CO2e/kg

FCPM

A similar evaluation of contributions was done for the feed-production stage (Table 4), especially since it was a hotspot in all impact categories. Rations in the Eastern provinces are more corn by-product rich while rations in the West use canola meal. 372


Table 4. Contributions of the feed production stage to impacts of crops and rations Hay

Corn

Dry Corn

Silage

Small

Soybeans

Grains

Rations

Rations

East

West

Overall weight

46%

20%

11%

10%

8%

6%

3%

Climate change

33%

10%

17%

15%

4%

13%

7%

quality

61%

4%

10%

0%

22%

2%

1%

Human health

38%

19%

13%

15%

9%

3%

2%

Ecosystem

There was variability in contribution based on type of crop. Corn grain and small grains had relatively more impact on climate change, mainly to fertilisation rates, while soybeans had less. The same trend was observed for impact on human health, as ammonia emissions also depended on fertilisation rates.With potential impacts on ecosystem quality, there were different factors in play. Corn silage, for example, benefitted from the highest yield per hectare (approximately 13 t of dry matter (DM)/ha) while soybeans were in the lower range, with a yield around 2 t DM/ha, each affecting impacts on land use. In evaluating sensitivity of certain parameters, it was important to consider the variable geopolitical and socio-economic context that influences practices, while remembering that agriculture is a complex system with many inter-related cause-effects chains that are difficult to model. With this in mind, and to perform a meaningful scenario analysis, a few ―what-if‖ scenarios were modelled based on current practices and wellknown alternatives (as opposed to marginal and emergent practices). These tested animal-replacement practices, alternative fertiliser types, fat supplements in feed, and manure management practices. Complex relationships between different areas of the life cycle stages (such as fertiliser use vs yield) were excluded for lack of sufficiently precise models. Reduction of animal-replacement rate is the only measure identified that allowed reductions of impact in three main hotspots (feed production, enteric fermentation and manure storage).

3.2. Socioeconomic Performance

The Specific Analysis assessed the behaviours of dairy farmers towards their stakeholders. ¡Error! No se ncuentra el origen de la referencia. shows the average socioeconomic performance of the Canadian dairy farms towards the farm workers, their local communities, the society and their suppliers and business partners (including the consumers).

373


* Due to data availability, a committed behaviour was not assessed for these indicators Figure 6.The average socioeconomic performance of the Canadian dairy farms It is made clear from this assessment that the Canadian dairy farms have an overall positive performance. It is furthermore obvious with respect to the agroenvironmental practices, whether it concerns water sources protection, manure storage or soil conservation. If this commitment is obvious from an environmental point of view, it is also significant in a socioeconomic perspective, as it also meets or exceeds expectations from society. The engagement towards local community is also significant, the vast majority of dairy farmers being involved in their communities in various ways. More can be done however in terms of cohabitation, towards minimizing odour propagation. The picture is also contrasted with regards to farm workers. Although dairy farmers provide overall working conditions that go beyond labour standards – to which they are mostly not legally subjected – there is room for improvements regarding various issues, such as professional training and communication of working conditions. The same holds true with respect to their suppliers and business partners, given that a majority of dairy producers do not usually consider their suppliers‘ performance in regards to social responsibility in their procurement decisions.The results present only the average performance. For each of these issues, there are producers having more socially responsible practices than others. This suggests that there is always room for improvements, now and in the future. The assessment also demonstrates that the Canadian dairy Boards (provincial and national) are, in average ,committed corporate citizens, especially with regards to local communities, as most of them support milk donation, scholarship and sponsorship to local organizations, even if these actions are not always part of a formal policy or agreement. When looking at the social risks potentially found in the supply chain upstream of the dairy sector, such as manufacturers of machinery, fertilizers, pesticides or pharmaceuticals, the prevalence of hotspots is generally low, with most businesses in Canada or the US. Some risks exist in a few links of the supply chains such as for fertilizer and oil extraction industries for example, where it was possible to document disturbing 374


practices of collusion as well as bank rolling techniques from subsidiaries companies of some major players. Potential hotspots were also identified in the North American grain and oilseed sector with regards to working conditions, as they are generally not protected by labour standards. The analysis also brought up public health issues, as well as conflicts of use of natural resources related to many industries, among which the pesticides and pharmaceutical sectors. Some links are also characterized by a lack of competition.

4. Discussion Applying LCA to production across Canada required a method that allowed and facilitated representation of differing provincial contexts, both in terms of practices (inventory) and geophysical conditions (CFs).Results showed that variability was driven by both aspects, depending on the indicator. By separating the two, it was easier to understand where reductions are possible and where observance of best practices is even more important (sensitive areas based on location). Achieving consistency in data collection and interpretation across Canada, however,was a challenge. Additionally, while great uncertainty exists in modelling emissions from soils, variability is also great due to organic (manure) and synthetic fertiliser application dosages and techniques.For the mostpart of dosages, only recommendations exist, from which assumptions were derived. The PHA identified potentially risky behaviours in the supply chain. Although the Canadian dairy sector has little power to influence these actors located far upstream, in a life cycle perspective, it falls under the responsibility of dairy farmers and their associations to get involved. The assessment serves as a first call to awareness on these issues.

5. Conclusion Overall, the LCA indicated an existing commitment from dairy producers to the supply chain‘s sustainability, which characterizes to an overall good performance – both at the environmental and socioeconomic levels. The main contributions to environmental impactcame from feed production for four of the five endpoint indicators. For climate change, as confirmed in the literature, enteric fermentation is the most important source of emissions (46%),followed by manure management (27%) and feed production (20%). The main sources of variability in climate change impacts among provinceswere linked to on-farm energy use(due to different grid mixes), followed by manure management and feed production. Variability in results is expected to be underestimated in feed production, however, due to the assumption that fertilisation recommendations were followed. The main sources of potential impact to ecosystem quality were caused by land use and aquatic ecotoxicity from mineral supplements, with a small contribution from acidification linked to ammonia emissions.Land use and ecotoxicity are both sensitive to geographic locations of farms. For human health, impacts were driven by respiratory inorganics, mostly NH3emissions from fertilisers, in housing and from manure storage. They were followed by NOx and SO2 emissions associated with fossil-fuel use for energy production in the different stages of lifecycle. An existing commitment to agroenvironmental practices, as identified in the socioeconomic assessment, suggests that evolving environmental recommendations could help sustain best practices and lower impact. With continuous improvement in mind target areas were identified. Among them is the possibility of better 375


tracking of fertilisation practices at the farm and to improve manure storage. It would be also profitable to provide guidelines on feed, based on impact. In a more socioeconomic perspective, it could be beneficial to promote more actively socially responsible behaviours among farmers, their Boards and eventually, their suppliers, to improve the sector‘s socioeconomic performance and, ultimately, its overall sustainability. This assessment provides the sector with an innovative, comprehensive and actionable roadmap to move in this direction.

6. References CIRAIG, University of Michigan, Quantis and DTU, 2012. IMPACT World +: A new global

regionalized

life

cycle

impact

assessment

method.

http://www.impactworldplus.org/en/index.php Couture JM, Parent J, Lafontaine M, Revéret JP (2012). Lessons learned from integrated environmental and socioeconomic life cycle assessments. in: Corson, M.S., van der Werf, H.M.G. (Eds.), Book of abstracts of the 8th International Conference on Life Cycle Assessment in the Agri-Food Sector (LCA Food 2012), 1-4 October 2012, Saint Malo, France. INRA, Rennes, France, pp.297-232October 2012 IDF (International Dairy Federation), 2010. A Common Carbon Footprint Approach for Dairy: The IDF Guide to Standard Lifecycle Assessment Methodology for the Dairy Sector,

http://www.idf-lca-guide.org/Files/media/Documents/445-2010-A-common-

carbon-footprint-approach-for-dairy.pdf Jolliet O, Margni M, Charles R, Humbert S, Payet J, Rebitzer G and Rosenbaum R, 2003. IMPACT 2002+: A New Life Cycle Impact Assessment Methodology. Int J LCA 8(6): 324-330. Humbert S, Margni M and Jolliet O, 2011. IMPACT 2002+ User Guide: Draft for version 2.2. Quantis, Lausanne, Switzerland. Available at: [email protected] Pfister, S., Koehler, A., and Hellweg, S., 2009. Assessing the environmental impacts of freshwater consumption. Environmental Science and Technology, 43(11), 4098-4104. Office of Dietary Supplements, 2011. Dietary Supplement Fact Sheet: Zinc, Office of Dietary

Supplements,

National

Institutes

of

Health,

USA

Gov,

http://ods.od.nih.gov/factsheets/Zinc-HealthProfessional/ Rochette, P., Worth, D., Lemke, B., McConkey B., Pennock, D., Wagner-Riddle C., Desjardins, R., 2008. Estimation of N2O emissions from agricultural soils in Canada. I. Development of a country-specific methodology, Canadian Journal of Soil Science, 2008, 88(5): 641-654 Sheppard S, Bittman S, and Bruulsema W, 2009. Monthly ammonia emissions from fertilizers in 12 Canadian ecoregions, Can. J. Soil.Sci, 90(1), 113-127 376


Sheppard SC, Bittman S, 2011. Farm survey used to guide estimates of nitrogen intake and ammonia emissions for beef cattle, including early season grazing and piosphere effects. Animal Feed Science and Technology, 166-167, 688-698. Swiss Center for Life Cycle Inventories (SCLCI) (2010) ecoinvent database v2.2. Available at http://www.ecoinvent.org/home/. UNEP/SETAC, 2009.Guidelines for Social Life Cycle Assessment of Products.United Nations Environment Programme. Paris. vanZelm, R., Schipper, A., Rombouts, M., Snepvangers, J., and Huijbregts, M. (2010). Implementing

groundwater

extraction

in

Life

Cycle

Impact

Assessment:

characterization factors based on plant species richness for the Netherlands. Enivronmental Science and Technology, 45, 629-635. Verones, F., Hanafiah, M., Pfister, S., Huijbregts, M., Pelletier, G., and Koehler, A., 2010. Characterization factors for thermal pollution in freshwater aquatic environments. Environmental Science and Technology, 44, 9364 - 9369.

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Comparative LCAs of ceramic tiles and bricks vs concrete equivalents in the Brazilian context Mia Lafontaine1, Karine Kikac1, Benoit Chappert2, Carlos André3 1Quantis Canada, 395 Laurier Ouest, Montreal, QC, H2V 2K3, Canada 2 Quantis France, 42, Bd Sébastopol, 75003 Paris, France 3 ANICER, R. Santa Luzia, 651-12°Andar, Centro-Rio de Janeiro, Brazil

[email protected] URL: http://www.quantis-intl.com

Abstract LCA is increasingly being employed by the construction industry to evaluate the environmental performance of buildings, materials, and construction practices, thereby identifying opportunities to improve the environmental performance, inform decision-making, and support marketing and communication efforts. In two consecutive studies, ANICER, the Brazilian association of ceramic, evaluated the life cycle environmental impact of roof tiles and building walls, each over 1 m2 of surface covered, using ceramic products and their concrete alternatives. While weight and thermal insulation are not necessarily the same, scenarios were adapted to the average situation for each case in Brazil, with sensitivity analyses testing for main alternatives of the average scenario. Regarding roofing solutions, ceramic tiles appear to have less impact than concrete tiles on Climate Change, Resource Depletion, and Water Withdrawal. The difference between the two options in terms of Human Health and Ecosystem Quality is however too low to be considered significant. In the case of wall materials, when comparing ceramic and concrete bricks, the same general conclusions hold true, although the differences are less appreciable, since both systems use equal amounts of mortar as well. Cast-in-place walls appeared as the worst option in almost all categories; however the inferior performance was only significant for Climate Change, Resource Depletion and Water Withdrawal categories. Both ceramic and concrete manufacturing processes require intensive heat inputs for two different purposes. While the calcination of cement constituting 20% of concrete requires a very high temperature, the baking of clay into ceramic requires a lower temperature for a longer period of time, for a total heat requirement of 126 MJ/m2 per ceramic tile versus 29 MJ/m2 per concrete tile. However, due to a the higher heat point required, calcination is achieved using fossil fuels, as oppose to the wood residues used in clay baking, such that the impact on climate change and resource depletion is significantly higher. For cast-in-place walls, the addition of more steel rods in the bill of materials than with brick walls increases the potential impact on Human Health and Ecosystem Quality because of fine particles emitted during the production process of the raw materials required to make steel. Steel production also requires a great amount of energy for its production, added to the impact on Climate Change and Resource Depletion. Key words: ceramic, brick, tiles, concrete, LCA, construction

Introduction LCA is increasingly being employed by the construction industry to evaluate the environmental performance of buildings, building materials, and construction practices. The Brazilian Association for the Construction Materials Industry (ABRAMAT) predicts an 8.8% growth in construction materials sales in Brazil in 2011, while sales are expected to grow by 48% for the next five years (Obelisk, 2011). In light of such a market growth, there is a great opportunity for ANICER, the Brazilian Association for the Ceramic Industry, to promote the advantages of ceramic products to help position this material with respect to functional equivalents. In this study, ANICER chose to compare the life cycle environmental impact of roofing tiles and exterior walls built with ceramic products and functionally equivalent concrete products.

378


Methods The comparative LCA of roof tiles and of exterior walls was done in accordance to the ISO 14040 series of standards, with a peer review panel commissioned to validate the reliability of the results and the level of conformance with the ISO standard. The panel was composed of one technical expert industrial ceramic production, one expert in industrial concrete production, and one LCA expert, leading the review panel. An additional Brazilian LCA expert also joined the review team for the second study, the comparing exterior walls. In the first of these two studies, the life cycle environmental impact of roof coverage over 1 m2 using ceramic roof tiles is compared with the same function fulfilled with similar concrete roof tiles. While weight and thermal insulation is not the same, the strength of the structure built to support the roof is considered equivalent in both cases and a sensitivity analysis evaluates the possible addition of an insulation layer below the concrete tiles to increase the thermal resistance. In the second study, the comparison is made between 1 m2 of exterior wall, built with ceramic bricks, concrete bricks or cast-in-place concrete. In each case, steel rods help reinforce the structure. The brick walls also require layers of mortar between each row as well as a mortar coating in each side. The scenarios compared were based on average construction scenarios supplied by ANICER. These were validated and supplemented by sensitive analyses following suggestions of the review panel. Primary data was provided by ANICER to best represent industry averages for ceramic tile production in Brazil. Primary data was also provided, as much as possible, for the concrete tile production. Secondary data was also extracted from ecoinvent, an internationally recognized life cycle inventory database. Impact Assessment Method Impact assessment classifies and combines the flows of materials, energy, and emissions into and out of each product system by the type of impact their use or release has on the environment. The method employed here is the peer-reviewed and internationally recognized LCIA method IMPACT 2002+ v2.2 (Jolliet et al. 2003, as updated in Humbert et al. 2012). This method assesses 16 different potential impacts categories (midpoint) and then aggregates most of them into 3 endpoint categories. They are presented along with the midpoint category for climate change, because of its individual importance, as well as with the inventory indicator for water withdrawal. In total, the five indicators are the following: 

Climate Change (in kg CO2-eq);



Human Health (in DALY);



Ecosystem Quality (in PDF*m2*yr);



Resources Depletion (in Primary MJ);



Water Withdrawal (in L).

IMPACT 2002+ uses the most current science with regard to global warming and offers the greatest consistency with data that might be presented elsewhere. The exclusion of biogenic carbon dioxide and monoxide, as well as a reduced emission factor for biogenic methane, avoids misleading computing of short cycle carbon emissions (absorbed and released by vegetation) along with carbon emissions from fossil fuels, previously stored underground permanently. Description of the Products Studied The studies focused on roofing tiles and exterior wall construction comparing ceramic with concrete alternatives. In the case of roofing materials, this was a comparison involving tiles only, as described in Table 0-1.

Table 0-1 - Key characteristics of the roof tiles studied Characteristics

Ceramic roof tiles

Concrete roof tiles

2.4

4.5

Roof coverage (tiles/m )

16

10.4

Life span (years)

20

20

Weight (kg) 2

For exterior walls, the analysis compared three different options for which there was a mix of materials: 379


ceramic bricks and concrete bricks, each with mortar and steel rods, and cast-in-place reinforced concrete. The characteristics of these options are summarized in Table 0-2.

Table 0-2 - Key characteristics of the wall products studied Characteristics

Ceramic bricks

Cast-in-place

Concrete bricks

reinforced concrete Brick weight(kg)

7.5

12

-

Wall thickness (m)

0.14

0.14

0.12

Wall construction

13 bricks

13 bricks

300 kg of concrete

15 kg of mortar

15 kg of mortar

9.48 kg of steel rods

0.4 kg of steel rods 62.5 kg of dry coating

0.4 kg of steel rods 62.5 kg of dry coating

22.8 l of water

5.75 l of water

5.75 l of water

40

40

(quantity of material for 1m2 of frontage) Mortar Coating (quantity per m2 of wall) Life span (years)

-

40

These characteristics are said to be representative of the average building roof and wall construction practices in the Brazilian context, for each material, based on ANICER knowledge.The 40 year life span of walls is based on the NBR 15575 standard, which requires that the vertical exterior joints of the walls meet the minimal requirement of a 40 year life span. Mortar is not renewed within those 40 years.

Results As can be expected, both studies highlighted similar advantages and disadvantages of the materials involved. Results comparing the tiles are depicted in Figure 15.Ceramic tiles appear to have less impact than concrete tiles on Climate Change, Resource Depletion, and Water Withdrawal. The difference between the two options in terms of Human Health and Ecosystem Quality is however significantly too small to be considered conclusive.

Comparison of Environmental Impact of Life Cycle Stages End-of-life

Concrete Tiles

Ceramic Tiles

Concrete Tiles

Ceramic Tiles

Concrete Tiles

Ceramic Tiles

Concrete Tiles

Ceramic Tiles

Concrete Tiles

Distribution

Ceramic Tiles

100% 90% 80% 70% 60% 50% 40% 30% 20% 10% 0%

Manufacturing (main components)

Climate change Human health Ecosystem quality ResourcesWater withdrawal

Figure 15 - Comparative LCA Results of ceramic and concrete roof tiles 380


When comparing ceramic and concrete bricks, the same general conclusions hold true, although the differences are less appreciable, since both systems use equal amounts of mortar as well. Cast-in-place walls appeared as the worst option in almost all categories; however the inferior performance was only significant for climate change, resource depletion and water withdrawal categories. These results can be observed in Figure 16.

Figure 16 - LCA results of exterior walls built with ceramic bricks, concrete bricks and castin-place walls For cast-in-place walls, the addition of more steel rods in the bill of materials than with brick walls increases the potential impact on Human Health and Ecosystem Quality because of fine particles emitted during the production process of the raw materials required to make steel. Steel production also requires a great amount of energy for its production, added to the impact on Climate Change and Resource Depletion. While the ceramic and concrete tile and brick shaping processes are roughly similar, both using natural resources with varying degrees of transformation to set into a solid and durable construction material, the manufacturing processes are very different. Concrete production requires limestone and clay to be calcined into cement at very high temperatures reaching 1450°C, producing an intermediate material that will set into the final product using only sand and water, air-dried at room temperature. For the production of ceramic tiles, oven temperature is lower, nearing 950°C while the entire tile must be baked, for a longer period of time. Meanwhile, the higher temperature of the clinkerization process requires a more intensive combustion, using mostly fossil fuels with some waste material recovery (such as tires). Since cement constitutes only about 20% of concrete tiles, the heat required per m2 of roof is much lower for concrete tiles than ceramic tiles, at 29 MJ/m2 rather than 126 MJ/m2. As a result of the use of fossil fuels for heat production, the concrete manufacturing process has a great impact on Climate Change and Resource Depletion. Conversely, the ceramic manufacturing process in Brazil uses residual wood chips as a heat source instead of fossil fuels, thereby significantly reducing impact on Climate Change during manufacturing while increasing impact on Human Health from fine particles emitted during combustion. For the reason listed above as well as longer distribution distances, concrete products are responsible for a higher impact in Climate Change and Resource Depletion. Higher impact on Climate Change also results from the CO2 emitted during the chemical reaction producing cement. Concrete products are also linked to a larger quantity of water withdrawal. They appear to have more impact on Ecosystem Quality; however the difference is not large enough to conclude, based on assessment method guidelines. Uncertainty and limitations An assessment of data quality identifies that data is generally of high or acceptable quality. Evaluating the influence of different parameters for which there was more uncertainty or alternative scenarios for packaging and installation indicated that only a significant change in distribution distances (large increase in ceramic and large decrease for concrete) could contribute to a change in results trends. 381


These sensitivity analyses as well as the uncertainty assessment performed using Monte-Carlo iterations have shown that the conclusions of this LCA are robust. The LCA conducted identifies some key parameters to consider when deciding between the use of ceramic or concrete products. Results of any LCA are a function of many factors, including the modeling assumptions, data employed, and choices in study boundary and functional unit. The context of this study should be considered when interpreting and applying the information presented in this report.

Conclusions The purpose of this study was to compare the environmental implications of choosing ceramic roof tiles over functionally equivalent concrete roof tiles for a surface of 1 m2. While the two processes are roughly similar, both using natural resources with varying degrees of transformation to set into a solid and durable construction material, the transformation processes are very different. Resultsshowed that because of the use of fossil fuels for heat production, the concrete manufacturing process has a great impact on Climate Change and Resource Depletion. Conversely, the ceramic manufacturing process uses residual wood chips as a heat source instead of fossil fuels, thereby significantly reducing impact on Climate Change during manufacturing while increasing impact on Human Health from fine particles emitted during combustion. Concrete tiles are also linked to a larger quantity of Water Withdrawal. They appear to have more impact on Ecosystem Quality, however the difference is not significant. Ceramic tiles on the opposite appear to have a higher impact on Human Health, yet the difference is once again not large enough to conclude, based on assessment method guidelines. An assessment of data quality identifies that data is generally of high or acceptable quality. Evaluating the influence of different parameters for which there was more uncertainty or alternative scenarios for packaging and installation indicate that variation in lifespan of less than 10 years does not affect the ranking of the option. Furthermore, the use of alternative processing of raw materials such as ―argilito‖ clay and artificial sand does not have significant impact on overall results. Neither does the addition of packaging on ceramic tiles, or the use of an aluminum-covered insulation layer under concrete tiles. These sensitivity analyses as well as the uncertainty assessment performed using Monte-Carlo iterations have shown that the conclusions of this LCA are robust. The information obtained through this LCA can lead to the undertaking of various actions to reduce the life cycle environmental impact associated with ceramic tile production, focusing on the following leads.



Since the emission of fine particles released during the combustion of wood chips is the

main contributor to Human Health impact, a focus on filtration of fines could be beneficial. 

Due to the importance of the transportation steps in all impact categories, alternative

measures could be investigated, such as shipment by boat or train, the use of biofuels, etc. Environmental relevance of these alternatives should always be validated with a life cycle approach specific to the context. This body of work was conducted for the ANICER, and the information provided here can be used public communication, following the critical review by a panel of expert. It is important to understand how this study was conducted so that its results and conclusions are applied appropriately. The typical limitations of LCA should be considered, along with the fact that several parameters are assumed to remain constant across the Brazilian geography evaluated, which may or may not be entirely accurate. This applies namely to manufacturing process, transportation distances, fuel mixes for firing and clinkerization, and building structure required to support the weight of tiles.

5. References Bauman H, Tillman A. 2004. The Hitchhiker's Guide to LCA: an orientation in life cycle assessment methodology and application, Lund Sweden: Student literature. Cement Association Canada (CEC). 2011. Canadian Cement Manufacturing Industry 1990 to 2009. http://www2.cieedac.sfu.ca/media/publications/Cement%20report%202010%20_2009%20data_%20Final.pdf Center for Clean Air Policy (CCAP). 2009. Sector-based Approach Case Study: Brazil. http://www.ccap.org/docs/resources/697/Brazil%20Cement%20Sector%20Case%20Study.pdf Humbert S, Margni M and Jolliet O, 2012. IMPACT 2002+ User Guide: Draft for version 2.2. Quantis, Lausanne, Switzerland. Available at: [email protected] Goedkoop MJ, Heijung R, Huijbregts M, De Schryver A, Struijs J and Van Zelm R 2009. ReCiPe 2008, A 382


life cycle impact assessment method which comprise harmonized category indicators at the midpoint and the endpoint level, First edition Report I: Characterisation; 6 January 2009, 126p. [online]. http://www.lciarecipe.net. IEA. 2007. Tracking Industrial Energy Efficiency and CO2 Emissions. International Energy Agency. http://www.iea.org/Textbase/npsum/tracking2007SUM.pdf Jolliet O, Margn M, Charles R., Humbert S, Payet J, Rebitzer G, Rosenbaum R. 2003. Impact 2002+: A New Life Cycle Impact Assessment Methodology. International Journal of Life Cycle Assessment 8(6): 324-330. National Institute for Standards and Technology (NIST). 2007. BEES 4.0. http://www.bfrl.nist.gov/oae/software/bees/ Obelisk International. 2011, January 20. Great Prospect for Investment in Construction Materials in Brazil. http://www.obeliskinternational.com/news60.php Portland Cement Association (PCA). 2008. Sustainable Manufacturing Fact Sheet: Tire-Derived Fuel. http://www.epa.gov/osw/conserve/materials/tires/pubs/brochure5-08.pdf Sindicato Nacional da Indústriado Cimento (SNIC). 2011. Etapas de Produçao. Consulted 12/07/2011. http://www.snic.org.br/ Swiss Center for Life Cycle Inventories (SCLCI). 2010. ecoinvent database v2.2. http://www.ecoinvent.org/home/. Udo de Haes HA, Finnveden G, Goedkoop M. 2002. Life-Cycle Impact Assessment: Striving towards Best Practice. Society of Environmental Toxicology & Chemistry: 272.

383


Sustainability assessment of chemical processes and/or products using life cycle assessment Dominguez-Ramos, A., Margallo, M., Aldaco, R., Irabien, A* Departamento de IngenieriaQuimica y QuimicaInorganica. Universidad de Cantabria. 39005 Santander (Spain)

+34 942 201597 *Email: [email protected]; URL: http://www.unican.es

1.

Introduction The document ―Our common future‖ (Brudtland and Khali, 1987) was published none

other than a quarter of century ago but the concepts of Sustainable Development and Sustainabilityare still valid and its technical implementation remains challenging. In this way, the development and application of metrics to track the progress towards Sustainability is still ongoing. It is well-known that the Sustainability Assessment is based on three main objectives: environmental, social and economic. Related to chemical processes and products, a multiobjective optimization needs to be solved taking into account the best simultaneous combination of these three objectives. In order to find a solution from a technical point of view, optimization procedures using multiobjective functions need to be developed. One of the main questions which remains open in the Sustainability Assessment using Life Cycle Assessment lies in the influence of the different variables in the objective functions and the way to be taken into account quantitatively in the optimization procedures. A technical way to carry out the Environmental Sustainability Assessment (ESA) of chemical processes and/or products has been developed using two main group of variables: Natural Resources Sustainability variables (NRS) and Environmental Burdens Sustainability variables (EBS). However, both group of variables are heterogeneous and they are

rarely normalized thus remained as different

objectives. Considering previously developed studies (Irabien et al., 2009) for normalization of EBS we apply the threshold for the different pollutantsfrom the European Pollutant Release and Transfer Register E-PRTR (E-PRTR, 2010), a similar procedure based on the values based on the use of resources in the Best Available Technologies given by the BREF documents (European Commission, 2006) was developed for the normalization of NRS. Therefore, NRS and EBS after normalization become homogeneous variables and the comparison between NR and EB can be accomplished. The aim of this work is to show a methodology to help the decision maker at choosing the best option within Environmental Sustainability Assessment, reducing complexity as the two main heterogeneous variables can be converted into comparable variables that can be further used in ESA optimization. A case study corresponding to the incineration of municipal wastes has been selected as example of the developed method. 384


2. Quantitative estimation of the Environmental Sustainability Assessment The ESA should consider the impact in the environment due to the use of natural resources (depletion/exhaustion) and the release of pollutants to the environmental compartments (air, water and soil). In this way, NRS includes the consumption of the primary resources such as energy, materials, water and land in the process and/or product so it can be describe by a NRS index 𝑋1∗ . Consequently; and on the other side EBS includes the main impacts to the air, water and soil due to the release of pollutants (emisions, effluents and wastes). According to the following procedure fourheterogeneous variables can describe NRS:  Energy (X1,1): this variable accounts for the total primary energy involved in the process (imports and exports) then it is necessary to account for the energy value of the primary energy resources employed (expressed as unit of primary energy per unit of mass of product).  Materials (X1,2): the total raw materials involved in the productionare considered here (expressed as unit of mass per unit of mass of product). Fuel and water are excluded from this variable.  Water (X1,3): it accounts for the total net water use in the process and in the cooling process (expressed as unit of mass of water per unit of mass of product).  Land (X1,4): the modified and occupied land for the process (expressed as unit of area by year per unit of mass). On the other hand, the description of EBS, which is based on an EBS index 𝑋2∗ , considers a total of twelve variables grouped into the releases to each environmental compartment:  Air (X2,1): Five different variables can be identified to assess the impact to the atmosphere: Atmospheric acidification (X2,1,1)as te·y-1 (ton equivalent per year)sulphur dioxide equivalent; Global warming (X2,1,2)aste·y-1carbon dioxide equivalent; Human health (carcinogenic) effects (X2,1,3)aste·y-1benzene equivalent; Stratospheric ozone depletion (X2,1,4)aste·y-1CFC-11 equivalent; andPhotochemical ozone (smog) formation (X2,1,5)aste·y-1ethylene equivalent.  Water (X2,2):In the case of the water compartment up to four environmental impacts can be considered: Aquatic acidification (X2,2,1) aste·y-1of released H+ ions; Aquatic oxygen demand (X2,2,2)aste·y-1oxygen; Ecotoxicity to aquatic life (X2,2,3)related to (i) metals(X2,2,3,1) as te·y-1copper equivalent, and (ii) other substances (X2,2,3,2) as te·y-1formaldehyde equivalent; andEutrophication (X2,2,4) aste·y-1phosphate equivalent.  Soil (X2,3): for the impact to the soil compartment, two variables are distinguished: Hazardous Solid Waste Disposal (X2,3,1) aste·y-1 hazardous waste and Total Non-Hazardous Solid Waste Disposal (X2,3,2) as te·y-1 non-hazardous waste. These variables are expressed interms of unit of mass of product.

Normally, the main release from the production processes is subject to Environmental Management (EM), so the impact to the concerned bodies of protection is at least partially 385


avoided. This EM practices are also not free of use of final resources. Therefore, the final quantity of pollutants stressing the environment comes from the transformation of natural resources into final resources (for the production process) and from the individual process (via EM and/or directly emitted). Therefore, different processes serving a similar functional unit can be studied in terms of the Gate to Gate boundaries. The risk associated with this kind of partial analysis (benchmarking basis comparison) is that the transformation of natural resources into final resources is not accounted. This is of particular relevance in the case of energy transformation because different process can have similar energy consumption per functional unit but the current impact is determined by how the transformation of primary energy into final energy is accomplished (i.e. composition of the grid mix for power consumption). Therefore, the impacts are attached to the suppliers of raw materials/energy, that is, the responsible agent of providing final useful resources. Similarly, the EM performed or not within the physical limits of the facility, is attached to the functional unit. The

Life Cycle Analysis methodology gives the full picture of the environmental

performance of the process or product by extending the boundaries to the whole life cycle (cradle to grave boundaries). Figure 1 shows the two main boundaries that can be identified: the Gate to Gate limits and the Cradle to Grave limits (strictly, the elementary fluxes to the environment would correspond to the arrows entering the EB box rather than to the output arrows). The Gate to Gate analysis (Ga-t-Ga) only considers the transformation of process resources (X1,i) into the corresponding functional unit and the emissions from the process (those subjected to EM or fugitive). In turn, the Cradle to Grave analysis (Cr-t-Gr) accounts for the transformation of the final resources (for the process and the EM) and the total release of pollutants to the three environmental compartments (X2,1; X2,2; and X2,3 ). Additionally, these two analyses can derived into three different analyses namely:  Cradle to Gate analysis (Cr-t-Ga): this analysis quantifies the impact due to the production of the resources to be used in the production process.  Gate to Gate analysis (Ga-t-Ga): as mentioned earlier it considers the transformation of process resources into the corresponding functional unit and the emissions from the process (fugitive and subjected to EM). Depending of the availability of the EM in the physical limits of the facility, it is feasible that a more detailed analysis could be made. For example, wastewater treatment plants could be included or not within the limits of the Ga-t-Ga. However, solid wastes (especially hazardous) are typically managed out of the facility. The combination of inventories for the Cr-tGa and Ga-t-Ga analyses will corresponds to the current available inventories in commercial databases.  Gate to Grave analysis (Ga-t-Ga): this analysis considers the impact from the final emissions to the environment and the impact from the consumption of final resources for the selected environmental management practice. Consequently, for the four variables identified for the assessment of the NRS and the twelve identified for the EBS, an assignation procedure could be performed in order to assess the contribution of each variable in the three analyses previously discussed. The information provided 386


here for NRS and EBS allows the decision maker to track the progress towards ES and to clarify the optimization procedure at least for the environmental pillar. While the capacity to reduce EBS in the Cr-t-Ga analysis is subjected essentially to the selection of greener suppliers, the decision maker could find process alternative to improve the profile in the Ga-t-Ga or in the Ga-t-Gr analysis.

Figure 17. Relationship between Natural Resources (X1,i) extracted from the environment and the Environmental Burdens (to air as X2,1), effluents (to water as X2,2) and wastes (to soil as X2,3) released to the environment due to the transformation processes and the environmental management. Physical limits of the facility in which the production process takes place includes the Ga-t-Ga boundaries and in some extension the EM.

As mentioned earlier, the different variables for EBS were compared thanks to the threshold limits taken from the European Integrated Prevention and Pollution Control (IPPC) policy, leading to normalized variables (X1,i*) using the E-PRTR reporting values. While the normalization procedure was described in detail previously, in order to help the decision maker, the normalization of variables for NRS (X2,i*) will be included as well using the references available from BREF documents for Best Available Technologies. Consequently, the two functions of ESA are converted into variables that can be compared.

3. Case study: Urban Waste Incineration 3.1.

Scope

As case study the incineration of amunicipal solid waste (MSW) facilityequipped with electricity and heat recovery located in Spain was utilized for the assessment of the different involved variables. According to the BREF document for this sector (European Commission, 2006), any MSW incineration facility will be using energy (from the waste mainly, support fuels and electricity), water, neutralizers and NOX removal agents. Table 1 shows the inventory used as 387


reference for the MSW facility. For the studied case, the use and transformation of land has not been considered. For the later inventory,data from Ecoinvent was used for the background data, considering Spain as geographical restriction for products/energy whenever available. The exported electricity was assumed to substitute the grid mix for Spain (at high voltage), whereas the final destination of the recovered heat was not provided and therefore not considered. In general, the geographical source of the different resources is Europe as explained in ecoinvent (2012).

388


Table4. Life Cycle Inventory for the selected MSW incineration facility (values per ton of waste as functional unit) Amount

Units

1.43

L

Comments

Source

ENERGY Input (import) Gasoil

Support fuel (0.03236 GJ·L-1 was used to evaluate the primary energy)

Gencat, EIA, Resolution 29/02/20008

Output (export) To the grid mix Soldelectricity

-0.128

MWhelec

(net value after consumption in the plant) (9.4737GJ·MWh elec-1 was used to evaluate

AEVERSU, 2010

primary energy) Minimum value from BREF Heat

-0.952

MWhthermal

Assumed recovery as district heating (3.956GJ·MWh thermal-1

was used to

(European Commission, 2006

evaluate primary energy)

MATERIALS Input(use of resources) Urea

1.62

kg

NOXremovalagent


Slacked lime

9.24

kg

Acid gas neutraliser


Activatedcarbon

1.63

kg


Antimony and compounds (Sb)

189

mg

E-PRTR, 2010

Carbonmonoxide (CO)

156

g

E-PRTR, 2010

Copper and compounds (Cu)

13.3

mg

E-PRTR, 2010

Arsenic and compounds (As)

189

mg

E-PRTR, 2010

Vanadium and compounds (V)

3.65

mg

E-PRTR, 2010

Manganese and compounds (Mn)

7.63

mg

E-PRTR, 2010

Output (emissionsto air)

389


Fluorine and inorganic compounds (HF)

3.98

g

E-PRTR, 2010

Chlorine and inorganic compounds (HCl)

27.0

g

E-PRTR, 2010

Lead and compounds (Pb)

82.6

mg

E-PRTR, 2010

Nickel and compounds (Ni)

17.6

mg

E-PRTR, 2010

Chromium and compounds (Cr)

30.2

mg

E-PRTR, 2010

Cadmium and compounds (Cd)

3.65

mg

E-PRTR, 2010

Nitrogen oxides (NOx)

1.72

kg

E-PRTR, 2010

Cobalt and compounds (CO)

3.65

mg

E-PRTR, 2010

Sulphur oxides (SOx)

0.139

kg

E-PRTR, 2010

Mercury and compounds (Hg)

14.3

mg

E-PRTR, 2010

PCDD + PCDF (dioxins + furans) (Teq)

37.1

ng

E-PRTR, 2010

Particles (PM10)

28.8

g

E-PRTR, 2010

Total OrganicCarbon (TOC)

30.5

g

E-PRTR, 2010

Thalium and compounds (Tl)

13.3

mg

E-PRTR, 2010

Carbondioxide (CO2)

0.325

ton

E-PRTR, 2010

Total phosphorus

32.2

mg

E-PRTR, 2010

Total Nitrogen

93.2

mg

E-PRTR, 2010

Chloride (Cl)

7.04

g

E-PRTR, 2010

Total OrganicCarbon (TOC)

447

mg

E-PRTR, 2010

Slag

81

kg


Flyashes

23

kg


660

kg

Output (emissionstowater)

Output (emissionstosoil)

WATER Input (consumption) Water

For flue-gas cleaning. Mean value for Spain MSW incineration facilities

390


3.2.

Natural Resources Sustainability (NRS)

As described previously, the NRS sustainability supports the benchmark comparison in terms of finaluseful resources such as energy, materials and water. Table 2 shows the values of the NRS for the selected MSW facility. Results from table 2 highlight the fact that whenever energy recovery is considered in the MSW facility this installation becomes a net exporter of primary energy. It is remarkable that arelatively large negative value of -4.93 GJ·ton-1is obtained as the process is able to export much more primary energy (-0.128 MWh elec·ton1

·9.47 GJ·MWh elec-1-0.952 MWh thermal-1·3.96 GJ·MWh thermal-1= -4.98 GJ·ton-1) than the amount coming

from the liquid gasoil (1.43 L·ton-1·0.0323 GJ·L-1=0.0461 GJ·ton-1) and of course assuming that the net calorific value of the waste is not considered. In order to treat 1 ton of MSW around 12.5 kg of materials and 660 kg of water are requested for the selected inventory. At this point, it is clear that, in order to understand if the previous values are acceptable, a reference should be used. Table 2 also displays the values for the minimum, mean and maximum values for the survey of MSW incineration facilities in the sector of the MSW incineration (European Commission, 2006). For the case of the materials, as different chemicals can be selected for the neutralization of acid gases, hydrated lime was used as reference.

Table 5.Natural Resource Sustainability NRS of the MSW facility per ton of municipal waste as functional unit. Values of 1 MWhth=9.4737 GJ and 1 MWhelec=3.956 GJ were used in order to obtained primary energy values (European Commission, 2006).

Analysed

BREF references NRS variables

MSW

Minimum

Mean

Maximum

ENERGY Import net

GJ primary

0.670

3.0858

6.134

0.0461

Export electricity

MWhelec

-0.279

-0.396

-0.458

-0.128

Export heat

MWhthermal

-0.952

-1,786

-2.339

-0.952

GJ primary

-5.74

-7.76

-7.46

-4.93

Hydrated/slacked lime

kg

6

14

22

9.24

Ammonia water (25% NH3)

kg

0.625

0.625

0.625

Urea

kg

1.62

Activated carbon

kg

1.63

Total

Net

Primary

Energy

Usage

X1,1

MATERIAL

Total raw materials used

X1,2

kg

6.63

14.6

22.6

12.5

kg

250

250

250

660

kg

250

250

250

660

WATER Water used in cooling Net water consumed

X1,3

391


From this table2, it is clear that a wide variation is possible in all three final resources variables X 1,i (in the case of water the energy consumption can vary noticeable depending on the presence of a heat recovery unit). Installations running under BAT technologies are those whose values are better than the mean values as pointed out in BREF (European Commission, 2006). Consequently, a fair comparison should be based on those mean ∗ calculated values. The normalized variables regarding NRS assessed as 𝑋1,𝑖 =

𝑋1,𝑖

𝑟𝑒𝑓

𝑋1,𝑖

are shown in Table 3:

Table 6.Comparison of dimensionless NRS variables for the selected MSW facility and the BAT reference Dimensionless NRS variables

MSW facility

BAT technologies (based on mean values)

ENERGY

X1,1*

-0.63

-1.00

MATERIAL

X1,2*

0.85

1.00

WATER

X1,3*

2.64

1.00

X1*

0,95

0,66

TOTAL (𝑋1∗ =

𝑋1,1 3

+

𝑋1,2 3

+

𝑋1,3 3

)

The usefulness of the proposed methodology can be seen clearly by means of table 3. While the energy balance in the facility is positive as it can be seen as a net exporter of electricity to the grid, the values of heat recovery makes 𝑋1,𝑖 to be below the BAT reference. Indeed, around 65% of the primary energy recovered in the BAT considered facilities is coming from heat recovery. Consequently, additional efforts should be made in order to reach a better energy recovery. If the energy analysis is restricted to electricity recovery, the value (-0.128 MWh·t-1) is still below the minimum stated as -0.279 MWh·t-1. Regarding materials consumption, the main chemical used is the hydrated lime so the values of 12.5 kg·t -1 are close to the reference of 14.6 kg·t-1. In the case ∗ of water, the consumption is around 2.6 times the reference. Therefore, as now three normalized variables (𝑋1,𝑖 )

are available, they are subject to directly summation so the NRS index 𝑋1∗ can be assessed as 𝑋1∗ =

𝑖=𝑛 𝑖=1

∗ 𝛼1,𝑖 𝑋1,𝑖 , 𝑛 ∈ 1,2,3 . Consequently, the NRS index depends on the weigth assigned to each final

resources variable. Whenever the three final resources are equally relevant, then 𝛼1,𝑖 =

1 3

∀𝑖 thus 𝑋1∗ =0,95 for

the selected MSW facility. However, as the process exports of primary energy, this normalized index should be carefully understood, as in this case, a lower energy recovery would lead to a lower value of the NRS index, leading to wrong conclusions. For most of the production process which are not net energy exporters, the less negative𝑋1,1 the worse performance meaning that the net primary export is lower which is clearly an undesirable situation. It is suggested that the inverse of the energy variable could be used at evaluating the index in these cases, so the lower the energy recovery the higher the energy index, then a poor performance will be translated into a higher composed index. Of course, the summation will lead to different values if different weights are chosen for energy, materials and water, but a more detailed analyses is requested to assumed a different set of values for 𝛼1,𝑖 . Consequently, the NRS will state that the analysis of the actual facility (summarized as 𝑋1∗ =0,95) is near the reference (𝑋1∗ =0,66) because a poor heat recovery is considered and especially because around 64% of the contribution to the NRS index comes from the relatively high water consumption.

392


3.3.

Environmental Burdens Sustainability (EBS)

As previously described, the EBS can be separated into three different steps: Cr-t-Ga (accounting for the EB associated to the natural resources), Ga-t-Ga (process emissions and use of resources) and Ga-t-Gr (disposal of the wastes), whose values are summarized into table 4 (annex 1), together with the normalization vector and the normalized values. In this way, some values from table 4 (annex 1) are negative in the GA-t-GA analysis, which come from the avoided electricity production allocated to this stage. The characterization factor from the TRACI method was used to incorporate the effect coming from the release of dioxins in the Human Health impact category as it was not originally defined.

The use of the normalization vector reveals that the most relevant impact category is by far the HHE, according to the normalization vector derived from the reporting threshold at E-PRTR. The advantage of using the approach described in this work is that the most relevant impact from the incineration of MSW is not GW or ATA or even WAS but HHE, as 𝑋2,1,4 =10.3, which is clearly larger that the next closer AOD with 𝑋2,2,1 =0.0201. The availability of normalized results let the assessment of the EBS index 𝑋2∗ to be assessed as 𝑋2∗ =

𝑖=𝑚 𝑖=1

∗ 𝛼2,𝑖 𝑋2,𝑖 , 𝑚 ∈ 1,2,3 . For the selected facility and hypothesis, 𝑋2∗ =10.3, thus HHE accounts for

almost 99.7% of the normalized impact, being this impact located in the Ga-t-Ga, because of the release of ∗ dioxins at the chimney of the facility. The impact to air 𝑋2,1 is the most relevant among environmental

compartments, as it accounts for 99.9% of the total dimensionless impact. These results are extremely dependent of the final emission of dioxins per ton of municipal waste incinerated. Consequently,the summation of normalized values of the different compartments leads to 𝑋2∗ =10.3 which can be used for comparison when different suppliers of the chemicals are considered or even better if a lower consumption of the chemical reagent is accomplished. While the comparison of 𝑋1∗ is possible in a similar way to benchmark study between alternatives, the comparison of the values in terms of EBS 𝑋2∗ with the reference makes few sense as each installation uses their own suppliers for energy, materials and water, this is the impact related to the production of final resources depends of each case.

4. Conclusions The IChemEsustainability metrics for the process industrieshas been extended in order to help at decisionmakingon the use of natural resources and management of environmental burdens. This methodology has been applied for a case study of a municipal waste incineration facility. As a result of the applied procedure, two dimensionless indexes regarding the use of natural resources 𝑋1∗ and the environmental burdens 𝑋2∗ were obtained: the normalization of natural resources was based on the data from facilities and the references from BAT technologies while the normalization of the environmental burdens was based on the threshold limit given by the European Pollution Release

393


5. Acknowledgments The authors gratefully acknowledge the financial support of the project ENE2010-14828 given the Spanish Ministry of Science and Innovation and the project LIFE08 ENV/E/000135: FENIX-Giving packaging a New Life project.

6. References AEVERSU, Asociación empresarial de Valorización de RSU (2010). http://www.aeversu.com/ Accessed 15 October 2010. Brundtland G, Khalid M (1987) Our Common Future: The World Commission on Environment and Development. Oxford University Press Oxford Ecoembes, EcoembalajesEspaña (2010) http://www.ecoembes.com/ Accessed 10 August 2010). E-PRTR, European Pollutant and Release Transference Register (2010). http://prtr.ec.europa.eu/ Accessed 22 October 2010. Ecoinvent (2008) The life cycle inventory data version 2.0 (2008). Swiss Center for Life Cycle Inventories. Ecoinvent. http://www.ecoinvent.ch European Commission (2006) Reference Document on the Best Available Techniques for Waste Incineration. Gencat, Departament de Medi Ambient iHabitatge de la Generalitat de Catalunya (2008b) Resolution of 29 February 2008 of the Environmental Integrated Authorization (EIA).http://mediambient.gencat.net/cat/. Accessed 4 October 2010. Irabien A, Aldaco R, Dominguez-Ramos A (2009) EnvironmentalSustainabilityNormalization of Industrial Processes. Computer Aided Chemical Engineering 26: 1105-1109.

394


ANNEX 1 Table 7.EBS for the case study assuming the three analyses considering as functional unit 1 ton of waste

Municipal Municipal Categoría de impacto

Unidad

AtmosphericAcidification

TonSO2eq /y

Global Warming

waste incineration

waste Municipal

Normalization

treated_GATE_GATE

CRADLE_TO_GATE wastetreated

vector

Normalizedvalues

X2,1,1

0,000479128

0,000037836

0,000516964

0,15

3,45E-03

TonCO2eq /y

X2,1,2

0,317818740

0,014305290

0,332124029

100000

3,32E-06

Human HealthEffects

TonBenzeq/y

X2,1,3

0,009620497

0,000647486

0,010267982

1,00E-03

1,03E+01

Ozone Depletion

TonCFC11eq/y

X2,1,4

-0,000000002

0,000000001

0,000000000

1,00E+00

-3,80E-10

Photochemical Ozone Formation

TonEthyle /y

X2,1,5

0,000018329

0,000001791

0,000020120

1,00E-03

2,01E-02

AquaticAcidification

TonH+rele /y

X2,2,1

-0,000013984

0,000003231

-0,000010753 0,1

-1,08E-04

AquaticOxygenDemand

TonOxygeq/y

X2,2,2

-0,000108194

0,000081315

-0,000026879 50

-5,38E-07

Ecotoxicity (Sea Water) Metals

Ton Cu eq/y

X2,2,3,1

-0,000000463

0,000000064

-0,000000399 0,05

-7,98E-06

Ecotoxicity (sea Water) Other

TonFormeq/y

X2,2,3,2

-0,000145464

0,000056475

-0,000088990 0,05

-1,78E-03

Eutrophication

kg PO4eq/Y

X2,2,4

-0,000081942

0,000212946

0,000131004

5,00E+00

2,62E-05

0,023401703

0,000000000

0,023401703

2

1,17E-02

0,081200000

2000

0,0000406

Ton Waste

hazardouswastes/y X2,3,1 Ton

Waste

non-

hazardouswastes/y X2,3,2

395


Life Cycle Assessment of the CILCA 2007 event PiaWiche* – Gil Anderi da Silva * Red Chilena de Análisis de Ciclo de Vida, Chile.

+56 974476306 [email protected] URL: http://www.redacv.cl Otherauthoraffiliation: Universidade de São Paulo, Escola Politécnica, Departamento de Engenharia Química. Av. Prof. Luciano Gualberto, Trav. 3, 380 Cidade Universitaria 05508-900 - Sao Paulo, SP – Brasil.

Abstract Purpose: CILCA is the most important Latin American conference on Life Cycle Assessment (LCA). It is organized biannually, and serves as a meeting place for the Iberoamerican community in the area. Up to date, the conferences have not included their own LCAs. We would like to contribute with this first, partial LCA of the 2007 version of the conference that took place in São Paulo, looking forward to making it a tradition of this meeting. Methods: Information for the inventory stage was extracted from the conference reports and meeting agendas, as kept by the organizing team. We considered the manufacturing of the welcome package and effects of travelling to and from the conference. Results: Transport related to the conference had a much greater impact than the manufacturing of the ―welcome package‖. In particular, effects were related to the use of fuel for transport.The categories of global warming potential (GWP100), human toxicity, and marine aquatic ecotoxicityshowed the highest results in the characterization stage of the impact assessment, however when normalized, the highest priorities were aquatic ecotoxicity, abiotic depletion and global warming potential. Conclusion: Transport was an environmental hotspot in the organization of the CILCA 2007 conference. It is suggested that for future events, the conference site be as close as possible to hotels and the airport in a city with light traffic. Key words: conference, LCA, transport, materials

Introduction With the advance in sustainability metrics, focus has expanded from products to include services and events. In the latter, it seems the leadership has been taken by governments, agencies and other institutions. These have published a myriad of documents to guide the organization of sustainable events, generally called ―green event guides‖ (Harding and Malone, 2010; Ministry for the Environment, 2010; Business Events Australia, 2011; National Tourism Development Authority, 2010; UNEP, 2009; Yale University, 2010; Delta Institute, 2011). There are also certifications and carbon footprint measures (ETH Zurich, 2002; Atmosfair, 2005; Native Energy, 2000). The new ISO 20121 stresses the importance of keeping records, useful to building an inventory, but does not give guidance into which impactassessment method to use. LCAis a good option because it is a science-based methodology that has ample inventories, and covers a number of impacts and substances, which are useful in aiding decision making processes while designing conferences. We found two studies related to the LCA of conferences, with a narrower scope, focusing on the use of cups during events (Garrido et al. 2007; Vercalsteren et al. 2010). But, to the best of our knowledge, there are no LCA studies practiced to a conference as a whole. CILCA (International Conference of Life Cycle Assessment) is an international biannual 396


conference focused on LCA work related to Latin America. Besides hosting trainings and presentations, it serves as a meeting point for the leaders of the Latin American LCA community. The city of São Paulo was host of the 2007 version of the conference, between the 26 th and 28th of February. This work presents a first approach to the LCA of a conference, defining some conventions and presenting the LCA of CILCA 2007. We hope that this work will start a tradition of measuring the impacts of CILCAs through LCA and helpfuture organizers to plan more sustainable meetings.

Methods There were 150 attendants from 10 countries (Brazil, Argentina, Chile, USA, Spain, France, Switzerland, Germany, Denmark and the Netherlands). There was information available for an 80% of attendees, which is used for calculating impacts from transport. Travel distances and times are estimated from the shortest routes rendered by Google Maps © from the participant‘s original address to the official hotel and conference centre. We separated attendees by travel length: 

People from São Paulo, or travelling less than 1.5 h by car are considered to travel home every day from the conference centre;



People whose travelling time by car was between 1.5 [h] and 5 [h] are considered to drive once into São Paulo and stay at the official hotel;



People whose travelling time by car was greater than 5 [h] are considered to take a flight to São Paulo and stay at the official hotel. Land transport to and from the airport is added. It is assumed that domestic flights arrived to the Congonhas airport and international flights arrived to the Guarulhos airport.

Transport is divided into land and air transport. Land transport modules were structured differently depending on whether it referred to Europe or South America. Air transport is divided between long and short distance flights. More details can be found below: 

Land transport in South America: PROCONVE L4 standard for Brazilian landtransport, with 11 km/l efficiency. Gasoline with 20% ethanol w/wis used. The Ecoinvent© dataset for Brazilian ethanol is used;



Land transport in Europe: includes the effects of infrastructure, assuming Euro III efficiency and fuel use;



Short distance flights: flights inside Brazil and in the European Union;



Long distance flights: overseas flights and those from the Americas with origin outside of Brazil.

Assumptions 

The event took place at SENAC (AvenidaEngenheiroEusébioStevaux, 823 - São Paulo, 04696-000) and the official accommodation for guests was the Blue Tree Towers Hotel (Av. RoquePetroniJr, 1000, Sao Paulo)



Original addresses for participants are taken from the records kept by the event organizers. Many of these were work addresses, but they were used as residential addresses in the absence of better information. 397




Air distances are estimated using the Mileage Calculator tool from www.webflyer.com;



The event lasted 3 days, meaning that everyone made at least six (6) trips to and fro their accommodation to the place of the event;

Emissions related to land transport in Brazil are estimated using the IPCC 2006 guidelines, based on kilometres travelled. We are aware that according to the IPCC method, this is more appropriate for calculating CH4 and N2O, rather than CO2, but we use it for all three gases (IPCC, 2007). The emission factors used can be found in Table 1. We only considered materials which had entries in Ecoinvent© datasets. SimaPro is used for estimating environmental impacts using its embedded databases and assessment methods. CML2001 method is used, with normalization ―World 1995‖.

Goal and Scope Definition The main product of CILCA 2007 was the event itself. The event's function is to lend a service: topresent information to participants. CILCA 2007 had 72 oral presentations, 19 poster presentations, 4 discussion panels/plenary sessions, and 4 courses. Each of these activities was considered as one information unit, giving a total of 99 units of information during the event. Goal of the Study: to determine the environmental impacts associated to the execution of the CILCA 2007 event. Functional Unit: the environmental impact of one unit of information given in CILCA 2007. Reference flow: one unit of information.

Inventory analysis Transport

The origin of guests is shown in Figure 19. There are four distinct groups: USA in green, Europe in red, Brazil in blue and South America (not Brazil) in yellow. Short distance flights are those in Europe or Brazil. All other flights are considered as long distance. Air transport accounted for 82.3% of the total distance covered in relation to the conference. Then, it is no surprise that air transport showed the greatest contribution to all impact categories. The 12 long-haul flights recorded account for 66% of the total air distance travelled by attendees, while 61 local flights only contribute with 34%. It is interesting that land transport between the hotel and the conference centre accounted for 23% of the total land transport estimated for South America. Welcome Package

A welcome package consisting of one blue nylon bag, one programme of the event, one note block, one CD-ROM with the proceedings, one pen, and one ruler was given to each attendee. Presenters also got one hard cover copybook. The characteristics of the paper booksgiven are presented on table 2. The pen and ruler came inside a paper envelope, which weighted 4.9 g. As there is no data available for the recycled plastic at the moment, we did not to consider the pen and ruler in the assessment. The conference CD was wrapped in a paper envelope of 17.8 g. Only the paper was considered, because there is no inventory information for the CD. The nylon bag has several parts, but for practical reasons it was considered as ―Nylon 600‖ with a weight of 337 g.

Impact Assessment SimaPro in its Faculty version is used to simulate the data. In order to ensure that the choice of method would not affect the conclusions, the inventory was analysed with all the methods available in SimaPro. The conclusion is similar for all methods: transporthas the greatest weight in results, and more specifically, air transport. 398


The environmental profile can be found in Table 5. From the table it can be seen that transportis dominant for the assessment results. In the normalized results, shown in Figure 20, aquatic ecotoxicity is the most impacted category. This is mainly associated to the extraction of crude oil and production of fuels for transport.

Interpretation Transport appeared as the greatest contributor to the impacts of the conference. This may be because there was more available information related to transport as to the welcome package, or perhaps because of its energy intensity. From the inventory it is clear that long-haul travelling is much more impacting than short flights. This can be seen bythe fact that although local flights accounted for an 83.6% of all flights, they covered only 33% of the total distance flown. Another surprising result was the importance of the distance between the hotel and the conference centre. In this case, it accounted for 23% of all land transportcalculated in South America. Even though land transport was not as important as air transport in the results, we conclude that the location of the conference hotel plays an important role in the total impacts, especially in a big city like São Paulo, where there is heavy traffic at all times, which increases emissions related to transport.

Discussion We found a few important differences between the LCA of a product and that of an event or service. The first of those is that activities taking place before the ―first extraction of materials‖ or ―cradle‖ of a service may play an important role in its life cycle impacts, especially if this service has a short lifetime. In the case of an event that lasts for a few days, planning may take several months. Within this time, meetings are organized, travels are arranged to meet collaborators and sponsors, and materials are used. We then propose that the planning stage should be considered within the LCA of any event, both to have more complete results, but also to orient decisionmaking, such as in the election and design of the welcome package, or choosing the event site. The second difference was the difficulty in accounting for some of the functions of the ―product‖. The various activities taking place during a conference, and the consideration of networking during coffee breaks made it hard to standardize the function of CILCA 2007 as a product. However, it was agreed that networking would be dismissed (given it is impossible to take account for it) and that every session or course would be considered as 1 information unit. The lack of local datasets and assessment methods was a limitation of this study, best reflected in the results for transport. There is a dataset for gasoline and other crude derivatives in Brazil, but it wasimpossible to use it given its format. We hope that this work starts a tradition for CILCA, and we suggest future organizers to keep good track of all materials and travels required for the organization and implementation of conferences.

References Harding., P., R. Malone (2010) Greener Events. http://www.oursouthwest.com/SusBus/greenerevents.pdf. Accessed 17 June 2011. Ministry for the Environment, New Zealand (2010) Major Event Greening Guide.http://www.mfe.govt.nz/publications/sus-dev/major-event-greening-guide/major-eventgreening-guide.pdf. Accessed 15 June 2011. Business Events Australia (2011) Key Facts. Green Check-list. http://anzmh.asn.au/rrmh11/GREEN_CHECK-LIST_fact_sheet.pdf. Accessed 10 June 2011. National Tourism Development Authority (2010) A guide to Running Green Meetings and Event .http://www.failteireland.ie/FailteCorp/media/FailteIreland/documents/Business%20Supports/Envi ronmental%20Guidelines/FI_GreenGuide_Web.pdf. Accessed 23 June 2011. UNEP (2009) Green Meeting Guide 2009.http://www.unep.fr/shared/publications/pdf/DTIx1141xPA-GreenMeetingGuide.pdf. Accessed 15 June 2011. Yale University (2010) Green Event Certification.http://sustainability.yale.edu/green-eventcertification. Accessed 9 June 2011. 399


ETH Zurich (2002) My Climate.http://www.myclimate.org. Accessed 13 June 2011. Atmosfair. Atmosfair website. 2005. www.atmosfair.de Native Energy (2000) Native Energy website. http://www.nativeenergy.com. Accessed 23 June 2011. Delta Institute (2011) Green Events & Destinations.http://www.delta-institute.org/content/greenevents-destinations. Accessed: 15 June 2011. Garrido, N., M. D. Alvarez del Castillo (2007) Environmental Evaluation of Single-Use and Reusable Cups.Int. J. LCA, 12:252 – 256. doi: 10.1065/lca2007.05.334. Vercalsteren, A., C. Spirinckx, T. Geerken(2010) Life cycle assessment and eco-efficiency analysis of drinkingcups used at public events. Int. J. LCA, 15:221 – 230. doi: 10.1007/s11367-009-0143-z IPCC (2007) 2006 IPCC Guidelines for National Greenhouse Inventories.In: S. Eggleston, L. Buendia, K. Miwa and Kiyoto Tanabe (eds.) Vol. 2, Ch.3 Mobile Combustion.Road Transport. Sistema Ambiental Paulista, Governo do Estado de São Paulo (2011)Inventário de fatores de emissão de gases de efeito estufa. http://www.ambiente.sp.gov.br/proclima/PDF/inventario_efeitoestufa.pdf. Accessed: 10 July 2011.

Figures and tables

Figure 18.Origin of attendees to the CILCA 2007 conference. Table 18. Emission factors for 3 Greenhouse Gases (used for Brazilian ground transport calculations) (IPCC, 2007; SistemaAmbientalPaulista, 2011). Gas Factor Unit CH4

0.0765

g/km

NOx

0.2

g/km

CO2 (fossil)

0.166871

kg CO2/km

CO2 (renewable)

0.026007

kg CO2/km

Table 19.Copybook and notebook parts and respective weight. All paper was 100% recycled paper. Hard cover copybooks Weight [g] Notebook Weight [g] Hard cover 191.8 Pages 77.6 Figure 19.Location of attendees to CILCA 2007. Participants Pages 411.3 Back 5.8 from Brazil are in blue, from Europe are in red, etc… First page (hard paper) 5.9 Bookbinding 2.1 Bookbinding 11.2 Plastic page 16 Plastic wrapping 5.3

400


Table 5.Environmental profile for CILCA 2007 (characterization results). Impact category Unit Total Transport Abiotic depletion Acidification Eutrophication Global warming (GWP100) Ozone layer depletion (ODP) Human toxicity Fresh water aquatic ecotox. Marine aquatic ecotoxicity Terrestrial ecotoxicity Photochemical oxidation

kg Sbeq kg SO2eq kg PO4eq

9,065.10 5,420.00 1,035.06

9,060.61 5,417.80 1,034.23

Welcome Package 4.48 2.20 0.83

kg CO2eq

1,398,274.21

1,397,696.53

577.68

kg CFC-11 eq

0.18

0.18

0.00

kg 1.4-DB eq

1,167,941.53

1,167,856.22

85.31

kg 1.4-DB eq

34,998.55

34,945.76

52.79

kg 1.4-DB eq

144,598,581.84

144,503,001.19

95,580.65

kg 1.4-DB eq

973.15

971.29

1.86

kg C2H4

229.82

229.72

0.11

Figure 20. Normalization results of the study.

401


Life cycle assessment of Chilean copper wire rods Mabel Vega* – Claudio Zaror* – Claudia Peña** – Carolina Scarinci** * University of Concepcion, PO Box160-C, correo 3,Concepcion, Chile. **Research Centre for Mining and Metallurgy, CIMM, Santiago. Chile

+56 41 2204197 +56 41 2247491 [email protected] URL: http://www.redacv.cl Chilean Life Cycle Assessment Network member

Abstract This paper presents a cradle-to-gate life cycle assessment of copper wire rods production in Chile. Copper wire rods constitute the main raw material in the production of electrical conductors, and could be made from fresh copper cathodes or from scrap metals. Wire rods manufacturing is an energy intensive operation, with significant consumption of electricity and fuels. Two manufacturing processes were considered here, namely, the Contirod® technology for the continuous melting, casting and drawing of copper wire rod, and the Upcast® technology for oxygen-free copper rod. Production and transport of copper cathodes, and fuels, as well as electricity generation and transmission were included within the system boundaries. Three sources of copper materials were considered in this study, namely, copper cathodes from electro-wining and smelters, and copper scraps. Primary data for process yields and energy consumption was obtained from local plants. Electricity supply was obtained from the Northern (SING) and Central (SIC) networks, and corresponding inventories were built on the basis of primary data. Impact categories included: depletion of abiotic resources, global warming, ozone depletion, photochemical ozone formation, acidification, and eutrophication potentials. Sensitivity to of results to specific energy consumption, and electricity and raw material sources was conducted. Results show that most environmental loads were associated to the production of copper cathodes, and inventories were highly dependent on the source of electricity. These results were discussed under the light of PCR requirements for such products. Key words: copper wire rod, Upcast process, Contirod process, LCA.

Introduction Chilean copper production accounts for 13.5% GNP, and is the largest productive sector in the national economy [1]. Most copper is exported as cathode and copper concentrate, and a little fraction of the former is locally used in piping and wire manufacturing. In particular, copper wire rods constitute the basis for the elaboration of different wire conductors. In Chile, two alternative wire rods (ASTM B-49) production processes are used, namely, Contirod ® and Upcast®. The former consists of fusion, continuous casting, and molding, using fossil fuels as main energy source. On the other hand, the Upcast ® process uses electricity for melting copper raw materials, 402


thus reducing the amount of dissolved oxygen. Given the importance of wire rods in the copper value chain, it is interesting to know the environmental impact associated with these process alternatives, under Chilean conditions. No information on this matter has been published so far, and this paper constitutes a first approximation to a life cycle assessment for copper wire rods.

Goal and scope This work aims to compare the environmental attributes of both Contirod ® and Upcast® wire rods production processes in Chile. Site-specific production conditions concerning cathode manufacturing and transport, electricity generation, fuels production, and wire rods making were used. The system boundaries follow a cradle-to-gate approach, from raw materials extraction to the wire rods manufacturing plant. Cut-off was set at 0.2 kg/ton wire for material inputs, and all process water and energy aspects were included. The functional unit was 1 metric ton (ton) of wire rods ASTM B-49, 8mm de diameter (Ø).

Methodology Inventorydata were obtained from primary sources, as well as publicly available reports and databases. National database were used in the case of energy generation, and transmission, and cathodic copper production. Electricity consumed in wire rods manufacturing was supplied by the Chilean Interconnected Central Network (SIC), whereas cathodic copper utilizes electricity from both SIC and the Northern Interconnected system (SING). Inventories were developed following procedures stated in ISO 14.040:2006 [2]and ISO 14.044:2006 [3]. Product Category Rules (PCR), coded CPC 41513 [4], developed according to ISO 14025:2006 [5], were used here. Ecoinvent database was used to provide inventory data on imported chemicals. Finally, SimaPro was used for data processing. Figure 1 illustrate the system boundaries for copper wire rods manufacturing, as defined in PCR/CPC 41513 Copper Wire Rod, in the EPD system.

Figure 1: Systems boundaries for PCR/CPC 41513 Copper Wire Rod, in EPD system [5] Environmental impacts were assessed on the basis of CML 2 Baseline v2.04 2000/World 1995 models.

Process Description Both Contirod and Upcast processes use similar grade A copper cathodes. A brief description of 403


main process characteristics are presented below. Contirod Process Grade A copper cathodes are meltedin a ASARCO shaft furnace and charged into a holding furnace, fired with fossil fuels, mainly natural gas and LPG (see fig. 2). Then, liquid copper is fed to a retention furnace before molding.Graphite is added as an oxygen barrier and the melt is cast between the two conveyer belts and then cooled down with soft water. The rectangular bar is rolled in a rolling mill to make a circular sectional area, meanwhile keeping cool with oil and soft water. In the last rolling stage, it fixing the wire rod diameter and get cold with isopropyl alcohol in crosscurrent. Finally the rod is coiled in 2 tons wire rod rolls [6]. Scrap cables Cathode grade A

Isopropylic alcohol

Melting furnace

Coiled up

Soft water and oil

Moulding

Texto Wire Rod

Molten copper NG o LPG

Molten copper

Copper rod

Cooling

Retention furnace

Wire Rod Ø 8mm

Rolling Emulsion + slag

Isopropylic alcohol waste

Soft water Graphyte

Figure 2: Process scheme of Contirod copper wire rod, at chilean plant. UpCast An electric fusion furnace is used to fuse copper cathodes, under an oxygen-free atmosphere (see fig. 3). This process produces rod from oxygen-free copper of a high drawability and plasticity, by continuous melting and vertical casting in an upwards direction. The charge in the form of highquality cathode is loaded to the induction furnace. The cathodes are melted in a melting furnace beneath a protective layer of charcoal. The cathodes are brought individually from upright stands by lifting machinery to a loader which places them in the furnace. The periodically-required copper alloy is transferred from the melting furnace through a sealed pipe to the casting furnace. The drawing rollers for the 8mm wire rod coiling machines are located above the casting furnace. The moulds for the graphite dies are set in the molten copper. The solidified rods are drawn upwards by drawing rollers. The graphite dies are held at a steady depth in the molten copper by a positioning control mechanism, which automatically raises and lowers the casting machine, depending on the level of the molten copper in the casting furnace. Each of the strands is directed to a coiler, to which the rod is passed from the drawing rollers by an automated speed control [7]. Scrap cables Cathode grade A

Cooling water

Moulding

Melting furnace

Cooling water Molten copper

Coiled up Wire rod Ø8mm Oxygen free

Molten copper

Retention furnace

Electricity

Electricity

Figure 3: Process scheme of UpCast copper wire rod, at chilean plant.

Results and discussion of LCA Life cycle inventory analysis

Table 1 and 2 show the mail inventory results

404


Table1: Life cycle inventory data for copper wire rod production by Contirod process in Chile Wire rod, copper Wire rod, copper Unit Contirod/SIC Contirod/SING Raw Material Gas, natural, in ground m3/ton 5.45 102 7.21 102 Oil, crude, in ground kg/ton 5.53 102 4.85 102 Shale, in ground kg/ton 3.59 10-4 3.63 10-4 Water, cooling kg/ton 1.32 102 4.15 102 Emissions to air Carbon dioxide, fossil kg/ton 4.67 103 6.27 103 1 Carbon monoxide, fossil kg/ton 2.33 10 2.32 101 -1 Dinitrogen monoxide kg/ton 6.03 10 6.16 10-1 Methane, fossil kg/ton 6.23 7.33 Nitrogen oxides kg/ton 5.73 101 6.31 101 Particulates, < 10 um kg/ton 4.27 101 4.30 101 Sulfur dioxide kg/ton 3.48 102 3.59 102 Emissions to water BOD5 kg/ton 1.10 101 1.01 101 -2 Chromium VI kg/ton 7.57 10 9.14 10-2 -1 Nitrate kg/ton 2.38 10 2.40 10-1 -1 Phosphate kg/ton 5.23 10 8.33 10-1 Sulfate kg/ton 1.80 102 1.84 102 TOC kg/ton 6.02 5,75 Emissions to land Cadmium kg/ton 3.84 10-7 9.62 10-7 -4 Chromium VI kg/ton 6.19 10 6.51 10-4 -5 Lead kg/ton 1.25 10 1.52 10-5 -6 Nickel kg/ton 6.20 10 8.49 10-6 -4 Zinc kg/ton 7.63 10 8.22 10-4 Table 2: Life cycle inventory data for copper wire rod production by UpCast process in Chile Wire rod, copper Wire rod, copper Unit UpCast/SIC UpCast/SING Raw Material Gas, natural, in ground m3/ton 5.09 102 7.02 102 Oil, crude, in ground kg/ton 5.62 102 4.87 102 Shale, in ground kg/ton 3.43 10-4 3.4810-4 Water, cooling kg/ton 1.37 102 4.46 102 Emissions to air Carbon dioxide, fossil kg/ton 4.68 103 6.42 103 1 Carbon monoxide, fossil kg/ton 2.34 10 2.33 101 -1 Dinitrogen monoxide kg/ton 6.04 10 6.18 10-1 Methane, fossil kg/ton 6.03 7.23 Nitrogen oxides kg/ton 5.74 101 6.38 101 Particulates, < 10 um kg/ton 4.26 101 4.30 101 Sulfur dioxide kg/ton 3.48 102 3.60 102 Emissions to water BOD5 kg/ton 1.10 101 9.94 Chromium VI kg/ton 7.62 10-2 9.34 10-2 -1 Nitrate kg/ton 1.95 10 1.98 10-1 -1 Phosphate kg/ton 5.31 10 8.70 10-1 Sulfate kg/ton 1.80 102 1.84 102 TOC kg/ton 6.00 5.72 Emissions to land Cadmium kg/ton 2.97 10-7 9.29 10-7 -4 Chromium VI kg/ton 6.56 10 6.91 10-4 -6 Lead kg/ton 9.44 10 1.25 10-5 405


Nickel Zinc

kg/ton kg/ton

5.10 10-6 7.19 10-4

7.61 10-6 7.83 10-4

Life cycle impact assessment

%

Figures 4and 5summarise the Contirod and Upcast impact assessment results, according to CML 2 Baseline v2.04 2000/World 1995. 100 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 0

Abiotic depletion

Acidification

Eutrophication


Ozone layer depletion (ODP

Human toxicity

Wire rod, copper Contirod/SIC CL Refractory, fireclay, packed, at plant/DE U Isopropanol, at plant/RER U Rolling mill/RER/I U Electricity, medium voltage, at grid SIC/Chile 2010 Natural gas, burned in industrial furnace low-NOx >100kW/CL U Disposal, inert waste, 5% water, to inert material landfill/CH U Disposal, used mineral oil, 10% water, to hazardous waste incineration/CH U

Fresh water aquatic ecotox




Copper, primary, at refinery/CL SIC U Steel, converter, low-alloyed, at plant/RER U Diethylene glycol, at plant/RER U Transport, lorry >16t, fleet average/RER U LPG, burned in industrial furnace 1MW, non-modulating/RER U Transport, barge/RER U Recycling non-ferro/RER U Treatment, sewage, from residence, to wastewater treatment, class 2/CH U

Analizando 1 kg 'Wire rod, copper Contirod/SIC CL'; Método: CML 2 baseline 2000 V2.04 / World, 1995 / Caracterización

Figure 4: Contirod Copper Wire Rod Impact process. CML 2 Baseline v2.04 2000/World 1995

100 95 90 85 80 75 70 65 60 %

55 50 45 40 35 30 25 20 15 10 5 0

Abiotic depletion

Acidification

Eutrophication


Wire rod, copper Upcast/SIC CL Charcoal, at plant/GLO U Transport, lorry >28t, fleet average/CH U Water, completely softened, at plant/RER U


Human toxicity


Copper, primary, at refinery/CL SIC U Refractory, fireclay, packed, at plant/DE U Electricity, medium voltage, at grid SIC/Chile 2010 Disposal, inert waste, 5% water, to inert material landfill/CH U




Graphite, at plant/RER U Rolling mill/RER/I U Transport, barge/RER U

Analizando 1 kg 'Wire rod, copper Upcast/SIC CL'; Método: CML 2 baseline 2000 V2.04 / World, 1995 / Caracterización

Figure 5: Upcast Copper Wire Rod Impact process. CML 2 Baseline v2.04 2000/World 1995 In both cases, copper extraction and refining account for most impacts. Independent on the wire rods manufacturing processes, the main environmental loads are associated with primary copper production. In turn, such process is highly influenced by the source of electricity, and sensitivity results are summarised below.

Sensibility analysis In Chile there are 2 main interconnected electricity networks, namely, a northern (SING) and a central (SIC) networks. The SING network features 99.5% thermoelectric sources, and only 0.5% hydroelectricity, whereas the SIC presents 52% renewable sources, mostly hydroelectric [8]. 406


Figures 5 and 6 present results on the sensitivity of environmental impacts to the electricity source in upstream modules, for Contirod and Upcast processes, respectively.

100 95 90 85 80 75 70 65 60 %

55 50 45 40 35 30 25 20 15 10 5 0

Abiotic depletion

Acidification

Eutrophication



Human toxicity

Wire rod, copper Contirod/SIC CL





Wire rod, copper Contirod/SING CL

Comparando 1 kg 'Wire rod, copper Contirod/SIC CL' con 1 kg 'Wire rod, copper Contirod/SING CL'; Método: CML 2 baseline 2000 V2.04 / World, 1995 / Caracterización

Figure 6: Contirod Copper Wire Rod Impact process comparison SIC/SING electricity matrix. CML 2 Baseline v2.04 2000/World 1995 100 95 90 85 80 75 70 65 60 %

55 50 45 40 35 30 25 20 15 10 5 0

Abiotic depletion

Acidification

Eutrophication



Human toxicity

Wire rod, copper Upcast/SIC CL





Wire rod, copper Upcast/SING CL

Comparando 1 kg 'Wire rod, copper Upcast/SIC CL' con 1 kg 'Wire rod, copper Upcast/SING CL'; Método: CML 2 baseline 2000 V2.04 / World, 1995 / Caracterización

Figure 7: Upcast Copper Wire Rod Impact process comparison SIC/SING electricity matrix. CML 2 Baseline v2.04 2000/World 1995 In both cases, the use of SING electricity yielded greater environmental impacts than SIC electricity, reflecting the greater fraction of thermoelectric production in the former. Abiotic resource depletion, global warming potential, water ecotoxicity, and photochemical oxidation, showed reductions around 24%, 25%, 11% and 11%, respectively.

Conclusions This work shows that the upstream processes, namely, extraction and refining of copper cathodes accounted for the main environmental loads in the copper wire rod life cycle. Additionally, the type of electricity generation technology has an important influence on such loads.

Acknowledgements The authors acknowledge the financial support from project FONDEF D09I1188. 407


References [1] Estadísticas Nacionales 2011. Banco Central de Chile. Ultima visita 09/12/12 http://www.bcentral.cl/publicaciones/estadisticas/actividad-economica-gasto/aeg01h.htm [2] ISO 14040.2006‖ Environmental Mangement. Life cycle assessment. Principles and framework‖ International Standard Asociation. Switzerland. 2006 [3] ISO 14044.2006 ―Evironmental Managemet. Life cycle assessment. Requirements and guidelines. ―International Standard Asociation. Switzerland. 2006 [4] ISO 14.025.2006. ―Evironmental Management. Environmental levels and declarations. Type III Environmental declarations. Principles and procedures‖ International Standard Asociation. Switzerland. 2006 [5] PCR/EPD Wire of copper, UN CPC 41513, ver. 1.0, EPD System, Swedden, 2012. [6] ―Continuous casting in the Copper Industry‖ P.F. Cuypers. University of Technology Netherlands. Eindhoven, 1987. ISBN 90-6757029-X http://alexandria.tue.nl/repository/books/289621.pdf [7] Polzka Miedz S.A. web page. Last visit at 12/03/12 http://www.kghm.pl/index.dhtml?category_id=383&lang=en [8] M.Vega, C.A. Zaror, C. Peña ―LCI of Chilean electricity generation‖. 4 th International Conference on Life Cycle Assessment in Latin America CILCA 2011. Coatzacoalcos, México 4-6 Abril 2011. [9] Effect of the electricity mix and ore fgrade on the carbon footprint of Chilean cathodic copper. C.A. Zaror, M. Vega, C. Peña, M. Bustamante. Conference of Metallurgist COM 2011, Montreal.

408


Energy balance of IVS 4500 wind turbine through a Life Cycle Assessment Ignacio Sagardoy(1), Sebastián Gortari(2) y Néstor Carlos Názer(1)

(1) Pontificia Universidad Católica Argentina Santa María de los Buenos Aires, Alicia Moreau de Justo 1300, Ciudad Autónoma de Buenos Aires, 1107, Argentina. (2) Comisión Nacional de Energía Atómica, Centro Atómico Bariloche, Av. Bustillo 9500, Río Negro, 8400, Argentina.

E-mail: [email protected]

Abstract With the goal of evaluating the environmental performance in terms of energy of a small wind turbine, an energy balance of the IVS 4500 wind turbine produced by INVAP Ingeniería S.A. was conducted. Using Life Cycle Assessment as methodology, the energy consumed to produce and utilize the wind system was compared with the one delivered throughout the lifetime of the system, being that one of 20 years. A detailed Life Cycle Inventory was made with materials and components that are part of the machine and the installation. Likewise, processes carried on to produce, install, maintain and decommission the system were inventoried. In order to reflect the reality, boundaries and scenario limits were established, evaluating the production stages, installation and maintenance, dismissing the last stage of the Life Cycle (dismantling) given its level of uncertainty. That stage was included, however, in the sensitivity analyses carried out. Energy storage systems (e.g. batteries) were neither included in the analysis, because of motives based in the scope of the work. The results of the inventory were translated into energy through a mixed analysis. This included the utilization of bibliographic data and specific LCA software. On the other hand, the electricity production of the wind turbine was estimated for installations representative wind conditions and typical losses for electricity transmission and control were included. There were also considered the times in which the system is not functioning because of regular maintenance stops or breakdown. Results account for the energy sustainability of this kind of electric production. In comparative terms, the energy produced throughout the lifetime of the machine is equivalent to more than 9 times the energy invested. From another point of view, the time in which the system returns the energy consumed in the different Life Cycle stages can be estimated in 2.2 years. Sensitivity analyses regarding key variables showed the strong influence on the energetic indicators (Energy Payback Time and Energy Yield Ratio) thatthe wind speed and also the kind of 409


transport used for the different movings have. Other variables such as lifetime and decommissioning of the installation (with energy recovery through material recycle) showed less influence. For all cases, even the leastfavorable, the energy balance resulted positive.

Keywords: wind turbine, LCA, energy balance.

1 Introduction With the rise experienced by alternative energy in general, and wind energy particularly, several debates have emerged about thebenefits and the environmental impacts generated by its use. The production and utilization of wind turbines for electric production come entailed -like almost every human activity does- with negative impacts on the environment. These last have to be identified and studied to be eliminated or minimized. The best benefits obtained by the use of wind energy lies in the low pollutant emissions associated and the use of a renewable resource while it‘s working. However, like any machine, wind turbines precise of materials and energy for its construction and it is that aspect at which some of the criticisms have been aimed.Sustainability of wind turbines has been questioned, arguing that the energy consumed to produce them is greater than the delivered later during its operation. In the last decade important studies about the environmental impacts of large wind turbines have been made, many of them conducted throughout Life Cycle Assessment (LCA) methodologies. These studies led to the identification of many negative aspects of the production and operation of wind turbines, some of which have been improved while others continue under study. Likewise, studies of wind turbines in the market have refuted the non energy sustainable argument, showing some results that in approximately eight months of operation the machines generate the energy consumed intheirlifetime.[1] These kinds of studies were made, mostly, by large wind turbine companies given the fact that the criticisms were mainly aimed at them. On the other hand, small scale wind energy, despite being used commercially since the beginnings of the XX Century, has not generated enough resources or interest for its environmental and social impacts to be studied, as well as the energy balances, as these last aspects became relevant. This work has as goal the identification of all the processes and materials, and the respective energy employed in the production of an INVAP Ingeniería S.A. IVS 4500 wind turbine through a Life Cycle Assessment. To carry out this joban exhaustive inventory was made of the components and the production processes of the machine, as well as other tasks that are performed throughout the Life Cycle of the turbine. The transformation from materials and processes to energy was made by the specific LCA software GaBi, complemented with estimations and other calculations. Once obtained the energy consumed during the Life Cycle of the wind turbine, the simulation software HOMER was used to estimate the energy generated by the turbine in its lifetime. Finally, both results were compared to obtain two energy performance indexes. On one hand, there 410


is the estimated time in which the wind turbine will produce the energy consumed over its Life Cycle; on the other hand, there is the calculated ratio between the total energy produced during the turbine‘s lifetime and the total energy consumed during the Life Cycle. This way, it is expected to answer the main hypothesis the work deals with: the energy sustainability of this industry.

2 Materials and method 2.1 Scope of the study

Figure 1: Scope of the Life Cycle Assessment

As mentioned in the introduction, this LCA involves only one environmental aspect of the production of the wind turbine, in this particular case, the energy aspect. Between the aspects that were evaluated in the work are the estimation of the energy consumed by the productions of the materials that make up the machine, the estimation of the energy consumed in the transport of the parts to the production plant, the estimation of the energy used in the production process inside INVAP Ingeniería S.A, and the estimation of the energy consumed in the installation and maintenance of the wind turbine. A subject that was partially approached is the energy balance including the final stage of the product, i.e. after the wind turbine has met its lifecycle. This is because there are no machines that have reached that instance, and at the same time, the company doesn‗t have at the present an established protocol for removal and dismantling of the produced wind turbines.

2.1.1 Function and Functional Unit

The wind turbine has as the only function the production of electric energy through the exploitation of the kinetic energy contained in the wind. Given the fact that these machines are produced with different characteristics (e.g. rated power, efficiency, lifetime, etc.), the Functional 411


Unit used in wind turbine Life Cycle studies is the energy unit, expressed in kWh, delivered to the user or the grid and generated over the lifetime of the wind turbine under certain wind conditions. In this LCA the Functional Unit is defined then as 1 kWh of electricity delivered to the user, for storage or water pumping, by the wind turbine operating under low wind conditions (IEC Class III)31.

2.1.2 Components and system boundaries

In this LCA, the system consists of the wind turbine, the tower and electricity cables to the place where the energy is stored or consumed. This means that even though the system is assumed as an off grid generating system, which mostly count with battery energy storage, for this study energy consumption related to such equipment won‘t be considered. This system boundary is caused by several reasons: one of the goals of the work is to be useful for comparisons with other off grid generation systems (e.g. solar), which also need storage; this turbine and other produced at the present can be used also without storage (either being connected to the grid or to water pumps); there are other ways of storage with different characteristics, so choosing one arbitrarily could difficult the comparison with other storage systems; finally, including the storage would exceed the scope and the resources to do it for it would need working with producers of such equipment.

2.1.3 Life Cycle stages

The typical stages that wind turbines go through during their lifetime can be defined as: production, installation, maintenance and operation, removal and dismantling at the end of the lifecycle. In the case of small scale wind energy, the first three stages cover concepts similar to those ofutility scale wind energy, but taken to a smaller scale. However, in the dismantling stage, the concepts, actions and resources contemplated are considerably different between small and utility scale wind energy.

Figure 2. Life Cycle stages. The last stage is not included in this LCA;however its influences are evaluated in the sensitivity analyses carried out. 31 International Electrotechnical Commission (IEC) classification for wind turbines were used arbitrarily in the LCA. 412


Production stage includes, on one side, the energy consumed to extract the raw material and to produce the primary materials that will make up the components of the wind turbine. On the other side, the energy consumed in the production of the wind turbines at the production plant of INVAP Ingeniería S.A. is considered, estimated only through the hours of processes and machinery used, according to the company‘s statements. Energy consumed by activities associated to the production of the wind turbine, such as marketing, advertising, financial services and research conducted by the company or third parties, will not be included in the study. Neither will be included the natural gas and electricity consumed by the entire production plant, avoiding allocation with other production lines. Installation includes the activities for the transportation of the wind turbine and additional elements (e.g. the tower) to the site and the activities for the erection.It involves the transportation of parts of the equipment in a pickup truckalong with the technicians that carry out the installation,and the transportation of other elements by short and long distance trucks. Maintenance consists in a complete annual inspection of the installation. The energy consumed in the transportation of specialized staff from a generic distribution centre, as well as the energy invested in the production of the parts replaced for wearing out and/or breakage, is taken into account in this stage for the calculation of the energy consumption 32. In this study the energy consumed for dismantling of the wind turbine will not be included in the energy balance. This is mainly due tothe fact that companies don‘t have recovery or final disposal programs for the machines. For that reason, the destiny of the materials and the way in which decommissioning of the installation take place, is often under the responsibility of the user. Also, regarding the end of the lifecycle of small wind turbines, there is the possibility of replacing only the wind turbine and continue to use the previously installed wiring and tower. This could result in important environmental benefits given the energy consumed not only in the installation but in the production of the materials also. However, in the sensitivity section, an estimation of the value that would represent an almost completedismantling (wind turbine and tower) and the energy that would be recovered if materials of the system were recycled was conducted.

2.2 Materials inventory

The Lifecycle Inventory was made exhaustively first through an information compiling work in the production plant, later completed in coordination with the producer. It includes all the material that is estimated will be consumed along the lifetime of the system, including the materials for maintenance and replacement of parts. Regarding the electronic parts ofwhich specific components could not be determined, a conservative estimation was made and the inclusion of generic communication and control electronics through the addition of 1 kg of aluminium was proposed. This approximation is

32

For this study, the complete replacement of the blades and other steel parts is included representing a weight of 10 kg. 413


believed to assure a minimum inclusion of the energy load related to the electronic devices. Information regarding material waste from production processes could not be gathered, consequently, an additional 20% of thesystem‘s components total mass was included, proportionally distributed between materials.

Component

Weight

Unit

Tower

2,042 Kg

Generator

62 Kg

Nacelle body

28 Kg

Electronics

27 Kg

Maintenance

18 Kg

Other

18 Kg

Yaw and control

17 Kg

Spinner and blades

16 Kg

Electric system

2

Kg

Total without gravel, sand and water* 732 Kg Total

2,230 Kg

Table1. Summary of weights by components.*These materials for the foundations are used almost without any transformation through industrial processes.This table doesn‘t include the extra 20% material proposed as process losses, which are distributed proportionally and are considered for the calculation of energy in processes and transport.

Material

Weight

Gravel*

814.4

Unit Kg

Sand*

566.4

Kg

Carbon steel

330.8

Kg

Cement*

177.6

Kg

Iron and steel materials (unclassified)

121.8

Kg

Water*

117.3

Kg

Cast iron

19.4

Kg

Resin and epoxy compounds

13.5

Kg

Copper and copper alloys

11.9

Kg

Alloy steel

10.9

Kg

Magnets

9.2

Kg 414


Fibreglass and GRP'´s

7.6

Kg

Resins y polyesters compounds

6.3

Kg

Plastics (PVC, polycarbonate, etc.)

6.1

Kg

Stainless steel

4.7

Kg

Ceramic compounds

3.1

Kg

Aluminium and aluminium alloys

2.9

Kg

Others

1.8

Kg

Polyurethane foam

1.4

Kg

Varnish, lacquers and similar

1.3

Kg

Other metals (lead, nickel, etc.)

0.7

Kg

Oils, lubricants, etc.

0.3

Kg

Total without cement, gravel, sand and water* Total sin gravel, sand and water. Total

2,230

554 Kg

732 Kg

Kg

Table2. Summary of weights by material. *The cement, gravel, sand and water are used for the foundations and anchors of the tower.This table doesn‘t include the extra 20% material proposed as process losses, which are distributed proportionally and is considered for the calculation of energy in processes and transport.

2.3 Processes inventory

The processes considered in the study can be divided into two. A group consist ofthe activities that are carried out inside the production plant of INVAP Ingeniería S.A. An inventory of machinery, powers and times required by each one of them was performed to cover this group.The other processes included in the analysis are those carried out by heavy industries for the production of primary materials such as cement, steel, aluminium, copper, etc. This group was incorporated in the analysis using the LCA software GaBi, which counts with a large database of industrial processes. The energy for the production of the materials later used by INVAP Ingeniería S.A. isevaluated through standard process data generated in the E.U. and the U.S.A. However, it is assumed thatthe difference between heavy industries processes in Argentina and those countriesshouldn‘t be substantial.

2.4 Transport

There are various transport distances included in the study. First, it is assumed that all the materials used by INVAP Ingeniería S.A. for the production come from Buenos Aires city, and it‘s done by long distance trucks. 415


Then, according to the information provided by the producer, a representative scenario for transport would be as described next. The wind turbine and other elements of the installation are transported with long distance trucks from the production plant to a distribution centre (sales, installation and maintenance) that is located 1,000 km away. Then a diesel fuelled pickup truck is used to transport the tower and the turbine to the site, located 500 km from the distribution centre. Energy consumption is then calculated in function of the kind of transport used and the load, covering a 1,500 km radius from the production plan, which includes most of the region with better aptitudes for wind exploitation in Argentina. The only materials that are not transported this way are the elements that make up the concrete for the foundation and anchors of the tower. The cement is assumed to be transported in long distance trucks to the nearest town to the installation site where the aggregates are bought and then transported together 100 km in a truck for short distances. This level of detail intends to be representative of the reality specially because these elements are together the heaviest group in terms of mass. It is assumed also that an annual maintenance is done over the twenty years of lifetime of the machine, with technicians being transported from the distribution centre. Maintenance routines are expected to be done coordinatedin order to inspect at least two installations every 1,000 km travelled. This assumption, suggested by the producer, is also considered conservative, being expected that maintenance routines include more than two installations.

Component / Task

Distance

Wind turbine, tower and othercomponents for the installation, excluding concrete materials. Includes 20% of 1,200 km waste material. 1,000 km Wind turbine, tower and other components for the installation, excluding concrete materials. 500 km

2,600 km

Transport characteristics Long distance truck (approximate payload 40 t) Long distance truck (approximate payload 40 t) Pickup truck, diesel fuel. (approximate payload 0.8 t) Long distance truck (approximate payload 40 t)

Cement.Includes 20% of waste material in the process. 100 km Sand and gravel. Includes 20% of waste material in the process. Return from erection and maintenance.

100 km

10,500 km

Short distance truck (approximate payload 20 t) Short distance truck (approximate payload 20 t) Pickup truck, diesel fuel. (approximate payload 0.8 t)

Table 3. Distance chart and transport characteristics considered in the LCA.

416


2.5 Energy consumed

From the Lifecycle Inventory and using a mixed model the total energy required along the lifetime of the system was calculated. The energy in the processes involved in the study has different origins, being most of them hydrocarbons, with a small participation of renewable energy. For the calculation, the volumes of the fuels consumed in the different productive processes are multiplied by their corresponding specific energy contents (calorific value). The following table shows the energy that is needed for the production of the materials that later, through processes inside INVAP Ingeniería S.A., make up each component of the system. This energy is obtained using the LCA software GaBi, representing heavy industries‘ common processesand includes the extra material that is proposed as waste in the study.

Component

Energy

Unit

Percentage

Spinner and blades

848

MJ

4.16

Generator

1,451

MJ

7.11

Electronics

1,703

MJ

8.35

Tower

11,337

MJ

55.57

Nacelle body

913

MJ

4.47

Yaw and control

891

MJ

4.37

Electric system

241

MJ

1.18

Other

3,019

MJ

14.80

Total

20,403

MJ

100

Table 4. Energy consumed in the production of the primary materials that make up the system‘s components.

To obtain the total energy required by component, the energy consumed in processes inside INVAP Ingeniería S.A. has to be added to the values presented in Table 4. That energy is 8,273 MJ, distributed as follows: Nacelle body (40%), Bearing and control (22%), Tower (17%), Generator (13%), Electric system (4%), Spinner and blades (3%) and Electronics (1%).

Stage of the Lifecycle

Energy

Unit

Percentage

Production

28,454.28

MJ

42.99

Installation

4,472.66

MJ

6.76

Maintenance

33,261.87

MJ

50.25

Total

66,188.81

MJ

100

Table 5. Energy by stage of the Lifecycle.

417


Table 5 shows the total consumption of energy during the Lifecycle of the system, divided by stage, and includes all energy flows considered in the study: production of materials, production processes, waste, and transport required for production, installation and maintenance.

2.6 Energy production

The estimated energy production of the wind turbine was calculated for an annual average wind speed of 7.5 m/s at 10 m above ground level. This is considered representative of typical installations done by INVAP Ingeniería S.A., which are done mostly in the argentine Patagonia. In the production over the 20 years there are losses related with the transmission of energy, efficiency of the electronics and time when the wind turbine is not in working conditions. This last is known as availability and can be caused by regular stops for maintenance, failures or breakdowns, and the time needed for the repair. In this study it is assumed as 95%. Due to the complexity of the subject and not enough information, in this study it is also assumed that there is no efficiency loss in the production caused by the natural wearing out of the components over the lifetime. Using the software HOMER and the data from the argentine National Wind Map, a production of 170,493 kWh (613,775 MJ) over the lifetime was estimated.

2.7 Energy balance

With the information generated for the LCA of the wind turbine it is possible to perform an energy balance between the energy produced during the lifetime of the machine and the one needed to produce, install and operate it. This balance, in addition to being represented by an index, can be expressed in terms of the time that the machine has to be working to produce the energy consumed over the different stages of the Life Cycle. Even though there are concept differences between the energy produced by the wind turbine (electric) and the one used for its production (mainly thermal and a minor share of electric), these indexes homogenize the values to obtain a result that can illustrate the energy balance of the system studied. It has to be mentioned also that the processes involved in the calculation of the energy consumed take into account the caloric energy needed to drive them. In other words, if it was assumed that the energy consumed in the different processes comes from sources that don‘t need other fuels to produce electricity (e.g. hydro or solar) the energy balance would be even more positive. This can be observed in the Primary Energy Payback Time (PEPT) used further on. The energy performance index in function of energy production time can be defined as Energy Payback Time (EPT) and can be expressed through the following equation:

𝐸𝑃𝑇 =

𝐸𝑛𝑒𝑟𝑔𝑦 𝑐𝑜𝑛𝑠𝑢𝑚𝑒𝑑 𝑜𝑣𝑒𝑟 𝑡𝑕𝑒 𝐿𝑖𝑓𝑒 𝐶𝑦𝑐𝑙𝑒 × 𝐿𝑇 𝐸𝑛𝑒𝑟𝑔𝑦 𝑝𝑟𝑜𝑑𝑢𝑐𝑒𝑑 𝑜𝑣𝑒𝑟 𝑡𝑕𝑒 𝐿𝑖𝑓𝑒 𝐶𝑦𝑐𝑙𝑒

Equation 1. Energy Payback Time, expressed in years. LT: Lifetime. 418


From this perspective, the time needed for the wind turbine to produce the energy that was invested in the different Life Cycle stages in our case is approximately 2.2 years33. If we consider the primary energy that had to be used to generate the energy consumed over the different stages of the Life Cycle, considering average efficiencies typical for thermal combustion machines, we can then estimate the PEPT.

𝑃𝐸𝑃𝑇 =

𝐸𝑛𝑒𝑟𝑔𝑦 𝑐𝑜𝑛𝑠𝑢𝑚𝑒𝑑 𝑜𝑣𝑒𝑟 𝑡𝑕𝑒 𝐿𝑖𝑓𝑒 𝐶𝑦𝑐𝑙𝑒 × 𝜂 𝑇𝑟𝑎𝑛𝑠𝑓𝑜𝑟𝑚𝑎𝑡𝑖𝑜𝑛 × 𝐿𝑇 𝐸𝑛𝑒𝑟𝑔𝑦 𝑝𝑟𝑜𝑑𝑢𝑐𝑒𝑑 𝑜𝑣𝑒𝑟 𝑡𝑕𝑒 𝐿𝑖𝑓𝑒 𝐶𝑦𝑐𝑙𝑒

Equation 2. Primary Energy Payback Time, expressed in years. LT: Lifetime. Using an average efficiency (ηTransformation) in theexploitation of fossil fuels of 0.35 we then obtain a PEPT of approximately 0.7 years (a little over 8 months). These two indicators have, nevertheless, a limitation when being used for comparisons, due to the fact that they don‘t clearly reflect the lifetime of a product, but they only point out the time to regain the energy consumed by the system. [13] Even for machines with a minimum lifetime established by a standard, it is believed appropriate the communication throw this other approach. For this reason, it has been proposed a nondimensional index that can be called Energy Yield Ratio, which simply shows how many times it is recovered the energy invested in the system throughout the Life Cycle stages.

𝐸𝑌𝑅 =

𝐸𝑛𝑒𝑟𝑔𝑦 𝑝𝑟𝑜𝑑𝑢𝑐𝑒𝑑 𝑜𝑣𝑒𝑟 𝑡𝑕𝑒 𝐿𝑖𝑓𝑒 𝐶𝑦𝑐𝑙𝑒 𝐸𝑛𝑒𝑟𝑔𝑦 𝑐𝑜𝑛𝑠𝑢𝑚𝑒𝑑 𝑜𝑣𝑒𝑟 𝑡𝑕𝑒 𝐿𝑖𝑓𝑒 𝐶𝑦𝑐𝑙𝑒

Equation 3. Energy Yield Ratio.

Using this indicator, the system studied shows an EYR of 9.3. This means that the energy produced over the lifetime of the machine equals to more than 9 times the energy invested according to our model.

2.8 Sensitivity analyses

In order to observe the influence of different factors on the energy performance indexes, several sensitivity analyses were conducted. Decreasing and extending the lifetime of the machine in 5 yearsdidn‘t cause significant variations on the indexes (EYR of 7.93 and 10.32; EPT of 1.89 and 2.42, respectively). On the contrary, wind speed and installation site showed important influence on the indexes (e.g. for an average wind speed of 8.5 m/s the EYR was 10.65 and EPT 1.88) as

33 Energy consumed over the Life Cycle (66,189 MJ); Energy produced over the Life Cycle (613,775 MJ). 419


well as the transport model. This last caused a marked difference for changes in the distance driven for the annual maintenance, resulting in EYR of 11.09 and EPT of 1.8 years when including three installations for each maintenance routine instead of two. In the case of considering the last stage of the Life Cycle, performing a complete decommission and recycling material, the indexes showed little difference (EYR of 9.6 and EPT of 2.1) because the energy regained was balanced with the extra energy needed for the transportation of the materials.

3. Discussion and conclusions If the energy is analysed by stage of the Life Cycle, the one with largest consumption is maintenance. In this last point, calculations showed that transport, done entirely by light vehicles (pickup trucks) represent nearly 97% of the energy. Regarding production, demanding component due to its mass (544.05 kg of industrially process materials). The main energy consumptions for that group of components are caused by the different steel parts (76%), transport (16%) and cement (7%). It can also be noticed that the energy consumed in processes inside INVAP Ingeniería S.A. (8,273 MJ) represent 30% of the total energy of production processes (28,454 MJ), being the other 70% consumed in the so called primary processes (e.g. the production of steel plates in the steel industry). Other materials that possess a remarkable specific energy load, though they don‘t have a large energy load in the total cause their masses are small in relative terms, are fibreglass and resin, epoxy paint and aluminium. Through the analysis of the different stages of the Life Cycle of the wind turbine the main aspects that affect the global energy performance of the systemcould be seen. This has proven to be positive even in highly unfavourable scenarios, leading to the conclusion that it is a sustainable activity in terms of energy produced and consumed. It can be noticed, by the main results but specially when observing the variations obtained in the sensitivity analyses, that even though the highest energy burdens occur during production and maintenance, a relevant improvement could be achieved by adjusting the variables of the second. Working on a few aspects related to maintenance the energy performance of the system could be improved importantly. This could be done by increasing the efficiency in logistics and in maintenance routines, minimizing the use of light vehicles (e.g. including several installations in each scheduled maintenance routine). Likewise, a constant maintenance throughout the lifetime of the system could not only reduce the times when the machine is not working due to breakdowns, but it could also extend the lifetime. Both improvements would cause an increase of the total energy production, making the energy performance of the system better.

4. Declaration This LCA was done as final dissertation to obtain the Environmental Engineering grade by the 420


first author, and the data and information used in this paper were taken from it. To get a copy of the complete report, write to the e-mail on the headings.

5. References [1] Life Cycle Assessment of offshore and onshore sited wind farms. Elsam Engineering. Vestas Wind Systems A/S. October 2004. [2]. Life Cycle Assessment of Electricity Production from a Vestas V112 Turbine Wind Plant. PE North West Europe ApS.Vestas Wind Systems A/S. February 2011. [3] Life Cycle Assessment of Electricity Production from a V80-2.0 MW Gridstreamer Wind Plant. Peter Garrett & Klaus Rønde. Vestas Wind Systems A/S. December 2011. [4]. Contaminación directa e indirecta producida por sistemas fotovoltaicos, eólicos y motogeneradores. Gustavo Nadal. Centro de Desarrollo de Proyectos, Fundación Balseiro, Fundación Bariloche. February 1995. [5] Comparative life-cycle assessment of a small wind turbine for residential off-grid use. Brian Fleck, Marc Huot. Renewable Energy, An International Journal. June 2009. [6] Life cycle environmental and economic analyses of a hydrogen station with wind energy. Ji-Yong Lee, Sanghyuk An, Kyounghoon Cha, TakHur.International Journal of Hydrogen Energy. December 2009. [7] The energy balance of modern wind turbines. Wind Power Note. Danish Wind Turbine Manufacturers Association. December 1997. [8] Energy and CO2 life-cycle analyses of wind turbines – review and applications. Manfred Lenzen, JesperMunksgaard. Renewable Energy Journal. June 2001. [9] Life cycle analysis of 4.5 MW and 250 W wind turbines. Brice Tremeac, Francis Meunier. Renewable and Sustainable Energy Reviews.January 2009. [10] International Standard IEC 61400-1, Wind turbines - Part 1: Design requirements. International Electrotechnical Commission.Third edition, 2005. [11] The Economics of Wind Energy. A report by the European Wind Energy Association. European Wind Energy Association. March 2009. [12] Beneficios ambientales del uso de paja de cereal para muros en edificios de la patagonia andina. Alejandro D. González, Conrado Tognetti, Simon Van den Heede. Asociación Argentina de Energías Renovables y Ambiente, Revista Avances en Energías Renovables y Medio Ambiente. Volumen 15. 2011. [13] Life cycle energy and greenhouse emissions analysis of wind turbine and the effect of size on energy yield. R.H. Crawford. Renewable and Sustainable Energy Reviews. July 2009.

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Life cycle analysis of handmade ceramic brick in chiapa de corzo, chiapas, mexico Argüello Méndez Teresa del Rosario, Beatriz Eugenia Argüelles León, Nguyen Molina Narváez Facultad de Arquitectura, Universidad Autónoma de Chiapas, Boulevard Belisario Domínguez Km1081, Calzada a Rectoría s/n, C.P. 29050, Tuxtla Gutiérrez, Chiapas, México.

++ 52 961 6150935 [email protected] www.unach.mx

Abstract With the aim of provide representative data of production conditions of handmade ceramic brick in Chiapa de Corzo, Chiapas, Mexico,and to propose strategies and alternatives for improving the quality of the material and to reduce the impact of this activity, the environmental impact associated with its production has beenevaluated, with the method of Life Cycle Assessment (LCA), calculated with the CML baseline 2001-Ecoinvent defined by the European Environment Agency, via the software SimaPro 7.1 PRé Consultants, according to the ISO 14040 series – in simplified form reducing the scope of the study to half life cycle, considering primary flows of the product system, materials and energy in production and distribution. The evaluation results are shown according to the functional unit: piece, front wall area of 130 cm2, including a description of the production system, inventory analysis (LCI) -. The major impacts identified into the process -Environmental impact assessment (LCIA) - are in the stages of raw material extraction and while burning the bricks, due to the changeof land use and furnaces emissions, also is here where occurs the major deficiencies in the quality of the product because the low thermal efficiency of furnaces. It is desirable to restore basic soil properties, reforest the extraction sites, innovate and improve the performance of the furnaces to increase product quality and reduce energy consumption without a rise in cost production. Keywords: life cycle analysis, handmade ceramic brick, building material

Introduction The impact ofhome construction activity in the city of Tuxtla Gutierrez(capital of the Mexican state of Chiapas)to the environment includes local affectations in the construction site due to changes in land use that increases urban sprawl and indirect affectations caused elsewhere and /or at other times caused by industries that supply building materials. In these homes walls of handmade ceramic bricks from the of Chiapa de Corzo area, are common. The brick fabrics are located at the margins of Grijalva River, there are around 29 fabrics, the occupation surface of each is about 1,000 to 5,000 square meters, each fabric has a production of 20,000 bricks every 15 or 20 days, and have a similar production system, handcrafted only, within the informal sector, which does not regulate the product quality or damages to the environment while product fabrication.34

Methodology The application of the LCA methodology was performed in a simplified form, with limited scope of the study to half life cycle (cradle to gate or half-life). Considering only primary flows of the 34

The quality requirements of bricks should perform are set forth in the NMX-C-036/037/038ONNCCE-2004 SCT-2000 Standard. The Laboratory Tests taken at the Engineering Faculty in UNACH showed that these bricks rarely comply the general specifications of construction. 422


systems (material and energy), from transporting raw materials to obtain the finished product and taking it to the construction area (phase of extraction of raw materials, production and distribution), without assessing the impacts during the use of these materials in the building and during its final phase, its disposal as waste (phases of use and disposal). Following the recommendations of the ISO 14044 standard for the development of the Life Cycle Inventory (LCI), a flowchart was created of the system processes (process tree) as a guide in identifying the input and output of material resources and energy of the system. After a census of the total handcrafted brick producers in Chiapa de Corzo, two brickyards were selected for specific analysis, where there were taken times and volumes of supplies during the brick-making process, according to the corresponding functional unit, by direct measurements. These measures may have some inaccuracies as they were not taken systematically like a continuous metering. The magnitude and significance of potential environmental impacts in the Impact Assessment phase of Life Cycle Assessment (LCIA), in compliance with ISO 14042, was quantified with the support of the database Ecoinvent Data v2, and method CML 2001 (baseline), by the Dutch program SimaPro 7.1, which considers the most important impact categories defined by the European Environment Agency: abiotic depletion, global warming, acidification, eutrophication, ecotoxicological impacts (terrestrial, marine and fresh water), toxicological impacts, Ozone depletionand photochemical oxidation.

General objective and goals The objective of this analysis was to obtain product information to generate a necessary database in inventories required in LCA of building materials for housing in the city of Tuxtla Gutierrez. The goals and limits of the system of the study range from transporting raw materials to the finished product and its distribution, considering only primary flows of the system (material and energy). The main function of handcrafted ceramic brick,measuring 26x12x5 cm and weighing 2.6 kg, whose material components are clay, coffee husks and water, is wall construction; each covers a frontal area of 130 cm2 (26x5cm = 130cm2). The functional unitis considered one brick.

Inventory analysis Production steps of the handmade ceramic bricks are: extraction and molding, drying,burning, and distribution: Loading and transport. See process tree (Fig. 1), and data of the inputs and outputs (Table 1).  Removing and mixing material. In situ, manual excavation and mixing with hand tools; water and coffee's husks are added to the mound of clay, forming a uniform mass (2 m 3) which lies 24 hrs, it is transported in metal wheelbarrows to the molding place.  Molding. The ―laying‖ area is leveled and cleaned manually, wateris spreadedto moist the surface and coffee husks or sand are added. The mold is made of wood and is called "moldera" It is cleaned with water inside a bucket to remove all types of old remains. With the mold resting on the ground, 5 pieces per mold are manually filled with clay, removing the excess before removing the mold, leaving the raw bricks laying on the soil.  Drying. It takes approximately 24 hours of initial sun drying, after that the bricks are tilted on its edge another 24 hours, to then,bricks are stacked in alternate arrayin a height of 9 rows,where are dried in the sun for another 3 to 6 days upon on the weather. In case of rain, raw bricks are covered with plastics (nylons-polymers) and / or metal foils.

423


Figure 1. Process Tree: handmade ceramic bricks.

 Baked. The dry raw bricks are carried in wheelbarrows to, which is made of brick or adobe; there bricks are fixedin alternate rows to allow homogeneous distribution of heat. Bricks are "burned" for two consecutive days, at a temperature between 1.000 to 1.037 ° C. These furnaces of direct combustion are heated mainly with coffee husks, and sometimes with firewood and tree branches, sawdust and shavings, or cobs ―olotes‖35 (dry waste biomassprimary waste), to complete these phase, the brick makers add disposed car lubricants, obtainedat auto repair shops in the area, the initial combustion of the furnace is startedby one or two disposed chopped tires. To keep the combustion air is inducted in to the furnace, using adomestic electric fan. Bricks remain inside the furnace three days after combustion is over. There are made about 20,000bricks in each furnace.  Loading and distribution. Bricks are loaded manually into3 tons trucks (one thousand pieces), and distributed to sale points and construction sites, at an average a distanceof 17 km.

TABLE 1. INPUT AND OUTPUT IN PRODUCTION - HANDMADE CERAMIC BRICK Input Output Products MATERIAL AMOUNT UN MATERIAL AMOUNT UN MATERIAL AMOUNT Clay 0.0019 m3 Emissions to air Handmade 1 ceramic 1.985 kg CO2 46.51 gr brick Water 0.197 l CO 0.010 gr (26 x 12 x 5 coffee husks 0.01273 kg N 2O 0.0003 gr cms) Usedtires 0.0001 pza NOX 0.048 gr Electricity 0.018140 l CH4 0.0002 gr Diesel 0.634356 mj NMVOC 0.003 gr

Impact Analysis The process of analyzing the environmental impact associated with the production of the handmade ceramic bricks used in building walls, only considers the impacts of the fuels used in transport vehicles, not by the use of the material (clay, husks and water), although it is considered as the affected area (land use), the calculation methods do not yet have a value for these resources 35

Olote (náhuatl:olotl), chócolo o zuro. 424

UN p


assignment. Also air emissions are recorded from the burning of residual biomass used in the baking phase, that contribute the global warming, in the other categories, the impact is subtracted from the total impact caused by the use of other fossil fuels, as it takes this as avoided product by recycling agricultural waste. TABLE 2. HANDMADE CERAMIC BRICK LCIA - Analyzing CHARACTERIZATION 1 pc. Method: CML 2 baseline 2000 V2.04 / World, 1995 Indicator: Characterization Diesel, burned Electricity, Biowaste, at Impact in building Unit Total hydropower, at collection category machine/GLO power plant/AT S point/CH S S Abiotic kg Sb eq 0.00038465 0.00038575 8.09E-09 -1.11E-06 depletion Acidification kg SO2 eq 0.00044563 0.0004464 5.62E-09 -7.77E-07 Eutrophicatio kg PO4--- eq 9.55E-05 9.56E-05 9.54E-10 -1.61E-07 n Global kg CO2 eq 0.06162167 0.05798238 1.67E-06 0.00363763 warming Decreased kg CFC-11 eq 7.19E-09 7.21E-09 1.02E-13 -2.58E-11 ozone Human kg 1,4-DB eq 0.03645125 0.03648306 1.35E-06 -3.32E-05 toxicity Freshwater kg 1,4-DB eq 0.00138226 0.00138476 3.10E-07 -2.81E-06 ecotoxicity Marine aquatic kg 1,4-DB eq 4.9602322 4.969814 0.00032199 -0.00990381 ecotoxicity Terrestrial kg 1,4-DB eq 6.25E-05 6.27E-05 8.04E-09 -1.66E-07 ecotoxicity Photochemic kg C2H4 1.14E-05 1.14E-05 2.97E-10 -2.97E-08 al oxidation Graph

1.

LCIA

characterization.

HANDMADE

CERAMIC

BRICK

LADRILLO CERÁMICO ARTESAL ROJO COMÚN. Chiapa de Corzo, Chiapas, México 120 115 110 105 100 95 90 85 80 75 70 65 60

%

55 50 45 40 35 30 25 20 15 10 5 0 -5 -10 -15 Abiotic depletion

Acidification

Eutrophication

LADRILLO CERÁMICO ARTESAL ROJO COMÚN



Diesel, burned in building machine/GLO S

Human toxicity


Electricity, hydropower, at power plant/AT S




Biowaste, at collection point/CH S

Analizando 1 p (LADRILLO CERÁMICO ARTESAL ROJO COMÚN); Método: CML 2 baseline 2000 V2.04 / World, 1995 / Caracterización

TABLE 3. HANDMADE CERAMIC BRICK-LCIA AnalyzingSTANDARDIZATION 1 pc. Mhetod: CML 2 baseline 2000 V2.04 / World, 1995 Indicator: Standardization Diesel, burned in Electricity, Biowaste, at Impact category Total building hydropower, at collection machine/GLOU power plant/AT S point/CH S Abiotic depletion 2.46E-15 2.46E-15 5.17E-20 -7.10E-18 Acidification 1.39E-15 1.39E-15 1.75E-20 -2.42E-18 Eutrophication 7.22E-16 7.23E-16 7.21E-21 -1.22E-18 Global warming 1.49E-15 1.40E-15 4.02E-20 8.77E-17 425


Decreased ozone Human toxicity Freshwater ecotoxicity Marine aquatic ecotoxicity Terrestrial ecotoxicity Photochemical oxidation

1.39E-17 6.38E-16 6.77E-16 9.67E-15 2.33E-16 1.19E-16

Chart

normalization.

2.

LCIA

1.40E-17 6.38E-16 6.79E-16 9.69E-15 2.33E-16 1.19E-16

1.99E-22 2.36E-20 1.52E-19 6.28E-19 2.99E-20 3.09E-21

HANDMADE

-5.01E-20 -5.80E-19 -1.38E-18 -1.93E-17 -6.19E-19 -3.09E-19

CERAMIC

BRICK

LADRILLO CERÁMICO ARTESAL ROJO COMÚN. Chiapa de Corzo, Chiapas, México

0e+0 Abiotic depletion

Acidification

Eutrophication

LADRILLO CERÁMICO ARTESAL ROJO COMÚN



Diesel, burned in building machine/GLO S

Human toxicity


Electricity, hydropower, at power plant/AT S




Biowaste, at collection point/CH S

Analizando 1 p (LADRILLO CERÁMICO ARTESAL ROJO COMÚN); Método: CML 2 baseline 2000 V2.04 / World, 1995 / normalización

Interpretation The geometric characteristics of these bricks are fairly regular, is in the mechanical characteristicswhere larger variations are observed from the cooking deficiencies. The resistance of the bricks varies according to their location inside the oven during the firing process, furnace thermal gradients produce bricks without uniform quality, these can be well cooked, "raw" or "molten" (complete loss of the chemistry and physics composition). The furnaces arenaturally (non mechanic)up drafted, have no cover or insulation. The absence of chimney flue causes incomplete combustion of used fuel because the lack of oxygen. The impact categories identified by the program Simapro, accusesthe generation of greenhouse gas, both fromthe fossil fuels used in transport trucks, andthe burned biomass in the oven; unfortunately, the software has not registryin the emissions database;of burning of tires, disposedmotor oils and greases,that are burned in the furnace, also soot is produced by the presence of volatile particles, containing significant amounts of PAHs, highly carcinogenic, and can generate significant amounts of liquids and solids that contain damaging chemicals to soil, water and groundwater aquifers. Moreover, exploited soil in the extraction of clay is devoid of vegetation and is seriously affected in their chemical and physical properties, left at the mercy of the rain, with the risk of landslides and washouts, by being composed of clay and fine silts.

Conclusion Using the LCA methodology, the realization of the ICV is the most complex part of the process by far, to quantify the list of raw material consumption energy (inputs), and emissions to the environment (outputs), of the flowcharts (process tree) of the production system, it is very important to seek the confidence of producers. Indeed, the results of the LCIA provided by the programs used by SimaPro have provided an estimate of the environmental impacts associated with the production of the handmade ceramic bricks in the sample area, since the data describes conditions of production in Western Europe, are enough to reflect about these production process and their environmental achievements,even whenits assessment is based on the basis of the total energy required for the production process.In 426


consequence, assessed pollution categories give information of the damage done by such provision and the use of such material as energy suppliers, also the category that includes resource depletion is to consider the possible exhaustion of fossil fuels that are obtained. However to these limitations, the ACV of the production process of the handmade ceramic bricks, has identified that the stage of cooking (baking) as the point at which the problems related to the emissions of pollutants, associated with energy consumption and to obtain quality products are critical. So that is that stage where improvements should be implemented in the technological process of production, taking care of environmental priorities and strengthening the businessopportunities, to reduce costs and improve market positions. If geometrical and mechanical qualities of bricks were corrected, product would improve, environmental, economic and social conditions in the region to build homes with this product, since is being local produced. Furthermore, regarding disturbances by the changeof land use, schemes are needed to restore the clay extraction sites to decrease CO2 non-energetic emissions from deforestation and land use changes that degrade their natural carbon sinks, which have a higher relative weight globally compared to the CO2 emissions from the energetic sector in the region.

Bibliography Asociación Española de Normalización y Certificación (2006), Gestión ambiental Manual de Normas UNE, AENOR ediciones, España. Wadel G., Avellaneda J., Cuchí A. (2010) La sostenibilidad en la arquitectura industrializada: cerrando el ciclo de los materiales. Informes de la Construcción. Vol. 62, No. 517: 37-51. Pre Consultants(2008), Introduction to LCA with SimaPro 7, Holanda. Reisman J. I. (1997) Emisiones al aire de la combustión de llantas usadas. EPA-600/R-97-115, CICA-EPA. Web: http://www.epa.gov/ttn/catc/dir1/tire_esp.pdf [Consulta: 01-06-2009] Suppen N. y Van Hoof B. (2005) Conceptos básicos del Análisis de Ciclo de Vida y su aplicación en el Ecodiseño [Documento] Centro de Análisis de Ciclo de Vida y Diseño Sustentable, México, United Nations Environment Programme (2003)Evaluation of Environmental Impacts in Life Cycle Assessment, Italia.

427


Life cycle assessment of corn-based ethanol via dry milling in Province of Santa Fe, Argentina Carla Pieragostini1, Pío Aguirre 2, Miguel C. Mussati3 INGAR Instituto de Desarrollo y Diseño (CONICET–UTN), Avellaneda Nº 3657 (S3002GJC) Santa Fe, Argentina.

++54 342 4535568 ++54 342 4553439 1

cpieragostini, 2 paguir, 3 [email protected]

URL: http://www.ingar.santafe-conicet.gov.ar/

Abstract Agricultural resources for energy purposes increased sharply in recent years. In Argentina, the legislation has imposed, like in other countries, the use of biofuels in blend with gasoline. The aim of this work is the identification of the life cycle points critical to the total environmental impact of anhydrous ethanol production in the Province of Santa Fe, which heads the corn yields in the country. A ―cradle to gate‖ analysis taking into account a valorization of co-products is performed. All the activities from the extraction of raw materials (farming subsystem – S1) to ethanol production (refinery subsystem- S2) are included, taking into account the use of DDGs as animal feed. An LCA study of corn-based ethanol corresponds to a country-specific approach is provided. As the global process is divided into two subsystems, two functional units are chosen: 1 kg of corn for S1 and 1 Mj of anhydrous ethanol for S2. Life Cycle assessment (LCA) is the methodology chosen through two LCIA methods:Eco-indicator 99 and Recipe 2008. Corn production, supplied energy in biorefinery subsystem and valorization of DDGs are the most relevant processes. Sensitivity analysis was performed to evaluate first the influence of the perspectives of the methods (hierarchical, egalitarian and individualist), and second the effects of deforestation, corn yield, transportation and energy matrix.The most relevant processesremain the same in three perspectives for both methods. It was observed a great environmental impact considering deforestation, particularly in human health and ecosystem endpoint categories. However, it is necessary a ―cradle to grave‖ analysis considering the use of biofuel in vehicles for a complete evaluation, which will be performed in a future work. Keywords: LCA, ethanol, corn, co-products, perspectives influence Abbreviations: Distillers‘ dried grains and soluble (DDGs), Life Cycle Assessment (LCA), Life Cycle Impact Assessment (LCIA),

Introduction Nowadays, as consequence mainly of oil reserves depletion and a day-to-day more environmentally conscious society, there are strong incentives to encourage research and development projects on renewable energies. In 2006, the National Law 26190 (El Senado y Cámara de Diputados de la Nación Argentina 2006) established that 8% of the national electric consumption in 2016 has to come from renewable energy sources.Biofuels, mainly biodiesel and bioethanol, constitute a renewable source of primary energy and its sustainable use is a valuable palliative to the current global energy crisis. In Argentina, a country with fertile soils climatologically favored for cultivation of a variety of cereals and oleaginous, the legislation has 428


imposedthe use of biofuels in blend with gasoline. This work aims at analyzing the environmental performance of corn-based ethanol production in the province of Santa Fe, which it has one of the highest corn yields in Argentina thought LCA methodology. A ―cradle to gate‖ analysis taking into account a valorization of co-products is performed.In addition, the influence of the perspectives (hierarchical, egalitarian and individualist) of the LCIA methods chosen and the effects of deforestation, corn yield, transportation, and energy matrix are evaluated through a sensitivity analysis.

Methodology Goal, functional unit and system boundary Goal and functional unit GLOBAL SYSTEM S1

LAND (Agricultural area)

SEEDS DIESEL FUEL

FERTILIZING SOWING HARVESTING DRYING

FERTILIZERS PESTICIDES

LAND (Agricultural area)

EMISSIONS TO AIR, SOIL AND WATER

TRANSPORT CORN

TRANSPORT

S2

ELECTRICITY NATURAL GAS CHEMICAL COMPOUNDS

CO2 DRY MILLING (milling, liquefaction, saccharification, fermentation, distillation, stillage treatment and dehydration)

HEAT

TRANSPORT ETHANOL 99%

DDGS

ANIMAL FEED

Figure 21: System boundary of anhydrous bioethanol production and co-product use. The studied system includes from raw materials production to anhydrous ethanolproduction and DDGs use via dry milling technology. The global system is divided into two subsystems: farming(S1) and refinery (S2), so two functional units are chosen: 1kg of corn and 1Mj for S1 and S2 respectively (Figure 1). For common stages, economic allocation is chosen, while for CO2 emissions carbon balance allocation is chosen,as USA reference case in Ecoinvent database (Jungbluth and Emmenegger 2007). System boundary Soil under continuous direct seeding for 40 years is assumed. Therefore, direct and indirect carbon emissions originated by land use changes are not included (Fargione et al. 2008; Searchinger et al. 2008). Thestudy takes into account seeds; biogenic CO2 captured by photosynthesis during plant growth; carbon content in soil; the energy content in corn;fertilizers and pesticides production; diesel fuel consumption; raw material transport; emissions to the air from combustion; and the emission to the soil from tire abrasion during the work process of agricultural machinery. Nitrogen oxides (NOx), dinitrogen monoxide (N2O), ammonia (NH3-N), methane (CH4) emissions to air as well as nitrate and phosphorous emissions to groundwater and phosphorous emissions to surface water are considered also. The applied pesticides are calculated as emissions to soil. In the corn drying process, emissions and heat waste to the air from combustion are taken into account, but waste and other emissions such as noise and dust are not. For transportation, trucks‘ production, maintenance, operation and final disposal are included, as well as construction, maintenance and disposal of roads. 429


Figure 22: Endpoint characterization of S1.

In S2, all stages until anhydrous ethanol production are considered: milling, liquefaction, saccharification, distillation, dehydration and stillage treatment, including the use of DDGS but without consider the use of biofuel. The electricity production and its transmission and distribution are taken into account. The process heat is produced by natural gas in an industrial furnace (>100 Kw). The considered process raw materials include sulphuric acid, soda powder, and N-based nutrients in the form of ammonium sulphate and diammonium phosphate. Mill infrastructure is included. As for trucks,construction, maintenance, operation and railway structure disposal are considered for train. Environmental impact assessment

The LCIA methods chosen are Eco-indicator 99 (Goedkoop and Spriensma 2001) and Recipe 2008 (Goedkoop et al. 2012), which are available in SimaPro 7.3.3 LCA software (Goedkoop and Oele 2008). Eco-indicator 99 involves eleven impact categories aggregated in three endpoint categories: Human health, which includes (i) carcinogenic effects on humans; respiratory effects on humans caused (ii) by organic substances and (iii) by inorganic substances; (iv) damage to human health caused by climate change; human health effects caused (v) by ionizing radiations and (vi) by ozone layer depletion. Ecosystem, that involves (vii) ecosystem toxic emissions; (viii) thecombined effect of acidification and eutrophication; and (ix) land occupation and land conversion considering only terrestrial ecosystem damage. Resources, that considers extraction of (x) minerals, and (xi) fossil fuels. Recipe taken into account the same endpoint categories but involves different impact categories. Human health includes (i) ozone depletion; (ii) climate change human health; (iii) human toxicity;(iv) photochemical oxidant and (v) particulate matter formation; and (vi) ionizing radiation. Ecosystem is the most different category, which includes (vii) climate change ecosystem; (viii) terrestrial acidification; (ix) freshwater eutrophication; (x) terrestrial, (xi) freshwater, and (xii) marine ecotoxicity; (xiii) agricultural and (xiv) urban land occupation; and (xv) natural land transformation. Finally, resources category remains equal. Regards to uncertainties about the correctness of the model, both methods are based on the concept of cultural theory (Thompson et al. 1990), identifying three different versions of damage model (Hofstetter 1998): Individualist version, where only proven cause effect relations are included using the short-term perspective; Egalitarian version that uses a precautionary principle, trying not to leave anything out; and Hierarchical version which includes facts that are backed up by scientific and political bodies with sufficient recognition. The hierarchical attitude is rather common in the scientific community, and among policy markets. In addition, four scenarios (E) are assessed in the performed sensitivity analysis: E0: Reference case: (i) grain yield of 7726 kg/ha, (ii) no deforestation, (iii) 80 and 20% of 430


transportation is by 28 t trucks and train, respectively, and (iv) 90% of energy matrix represented by hydrocarbons- based vectors (49.45% natural gas and 40.85% oil). E1: Deforestation. Transformation from forest to arable land, CO2 emissions caused by land conversion (55 t/ha), and biomass from forest cleaning (193 t/ha), are considered (Panichelli et al. 2009). E2: Lower grain yield: 5500 kg/ha. E3: 50% allocation for each transport mode (28 t trucks and train). E4: A larger contribution of renewable energy sources in energy matrix is considered: 6% nuclear, 20.73% natural gas, 0.957% wood, 0.019% coal, 0.33% biofuels, 17.27% oil, and 46.694% hydraulic energy.

Results Characterization

Both subsystems, S1 and S2, and the global system are characterized according to the LCIA methods. In figure 2 the endpoint characterization of S1 is showed. The use of fertilizers and resources, seed production, harvesting process, fertilizersproduction and corn drying are the most relevant processes. In the case of Resources category there are not significantly differences between the methods (less than 2% in the most relevant processes) but in the others categories the differences regard to processes contributions are bigger (until 60% in ecosystem category). Regard to S2, corn production has the most significantly contribution for human health and ecosystem category according to both methods (Figure 3).

Figure 23: Endpoint characterization of S2. However, itsinfluence is bigger according to Eco-indicator 99 than Recipe (until 1.6 times for Ecosystem category). For the lastmethod, natural gas and heat supplied have more influence in the both endpoint categories. Again, in resources category the contributions are equal for both method and evenly distributed in corn production, natural gas and heat supplied. Finally, the use of the DDGs has positive impact in both methods, particularly in ecosystem (Figure 4). The contributions are very similar for bioethanol production and use of DDGs, except in ecosystem category where the impact according to Recipe is 6.6 times than the impact conforming toEco-indicator. Sensitivity Analysis

So far, the results are based on the hierarchical perspective of both methods. Following, the other two ones (individualist and egalitarian) are compared to observe if the results remain the same, 431


independently of the perspective considered. The most relevant processes remain the same but its contributions are modified in some cases. For both methods, in resources category there are differences less than 6% between perspectives. The differences in human health category are less than 10% for both methods while in ecosystem category there are differences more than 40% for Recipe method. The differences among scenarios are not very significantly (less than 20%), except for deforestation (Table 1). This scenario increases the impact since 11 times in Human Health and ecosystem categories.

Figure 24: Endpoint characterization of Global system.

E0: Reference case E1: Deforestation E2: Grain yield E3: Transportation matrix E4: Energy matrix E0: Reference case E1: Deforestation E2: Grain yield E3: Transportation matrix E4: Energy matrix

Human Health Recipe 8.548 100.000 9.578 8.386 7.928 Eco-indicator 21.773 100.000 25.813 21.225 20.235

Ecosystems

Resources

-0.031 100.000 0.037 -0.034 -0.042

95.428 95.443 100.000 93.775 89.318

-0.949 100.000 -0.920 -0.950 -0.952

95.554 95.569 100.000 93.787 89.344

Table 21: Comparison among scenarios.

Conclusions A country-specific approach for LCA study of corn-based ethanol is provided. The emissions caused by the use of fertilizers and resources, land use for seed production and resources used in harvesting process, fertilizers production and corn drying have the most relevant environmental impacts in farming subsystem. This subsystem is one of the most relevant processes with natural gas and heat supplied in biorefinery process. The valorization of DDGs has an important positive impact, particularly because of the land use avoided. As fossil fuels use has significant impacts in all studied stages, biomass fired thermal systemsto energy supplied can be improve theenvironmental performance of global system. Although the contributions of the processes vary according to each LCIA method, same relevant processes are identified. The biggest differencesare found in Ecosystem category,where, for example, Recipe taken into account toxicity in water, while Eco-indicator considers only terrestrial toxicity. 432


Finally, deforestation has a very significant environment impact, so the indirect effects of land use change should be considered since an agricultural frontier extension can lead to the possibility of affect protection areas. Although no methodological standards exist on this issue (Cherubini and Strømman 2011), more data are needed to determine the part of deforestation attributable to cornbased ethanol production in Argentina.

Acknowledgements The financial support from the ConsejoNacional de InvestigacionesCientíficas y Técnicas (CONICET) and the AgenciaNacional de PromociónCientífica y Tecnológica (ANPCyT) of Argentina is gratefully acknowledged.

References El Senado y Cámara de Diputados de la Nación Argentina., 2006. ―Ley 26.190: Régimen de fomento nacional para el uso de fuentes renovables de energía destinada a la producción de energía eléctrica.‖ Fargione, J., Hill, J., Tilman, D., Polasky, S., and Hawthorne, P., 2008. ―Land clearing and the biofuel carbon debt.‖ Science, 319, 1235–1238. Goedkoop, M., Heijungs, R., Huijbregts, M., De Schryver, A., Struijs, J., and Van Zelm, R., 2012. ReCiPe 2008 A life cycle impact assessment method which comprises harmonised category indicators at the midpoint and the endpoint level. Goedkoop, M., and Oele, M., 2008. ―Introduction to LCA with SimaPro 7.‖ Amersfoort: Pre Consultant. Goedkoop, M., and Spriensma, R., 2001.The Eco-indicator 99. A damage oriented method for Life Cycle Assessment. Methodology Report, PRé Consultants B.V. Hofstetter, P., 1998.Perspectives in Life Cycle Assessment; a structure approach to combine models of the technosphere, ecosphere and valuesphere.Kluwers Academic Publishers. Jungbluth, N., and Emmenegger, M. 2007. Life Cycle Inventories of bionergy. ecoinvent report. Panichelli, L., Dauriat, A., and Gnansounou, E., 2009. ―Life cycle assessment of soybean-based biodiesel in Argentina for export.‖ International Journal of Life Cycle Assessment, Renewable resources • case study, 144–159. Searchinger, T., Heimlich, R., Houghton, R. A., Dong, F., Elobeid, A., Fabiosa, J., Tokgoz, S., Hayes, D., and Yu, T., 2008. ―Use of U.S. croplands for biofuels increases Greenhouse Gases through emissions from land-use change.‖ Science, 319, 1238–1240. Thompson, M., Ellis, R., and Wildavsky, A., 1990. Cultural Theory. Westview Print Boulder.

433


Analysis of the procedures for allocation criteria and the system boundaries in LCA: study case of a toothbrush Agnes Narimatsua*– Fabio Puglieria – Diogo Aparecido Lopes Silvaa - Fábio Rangelb – Aldo Roberto Omettoa a

Department of Production Engineering, São Carlos School of Engineering, University of São Paulo,

Trabalhador São Carlense Avenue 400, São Carlos,13566-590, Brazil b

Johnson & Johnson Consumer, Rodovia Presidente Dutra, km 154, 12240-907, São José dos Campos, Brazil

* Corresponding author. Phone: +55 12 81571606 E-mail address: [email protected]

Abstract The growing awareness regarding the importance of environmental protection and the possible impacts associated with products has led to an increased interest in developing methods to better understand and reduce these impacts. LCA is a technique that meets this goal, since it allows identifying which stages of the life cycle have greater contribution to the environmental impact. Life Cycle Assessment (LCA) is standardized in accordance with ISO 14040 and 14044 references. This study performed a comparative LCA between 2 toothbrushes in order to evaluate the impact of two allocation criteria: presented by Wenzel et al. (1997) and the ILCD Handbook (2010). Eco Reach Essencial Johnson&Johnson® (EREJJ) toothbrush contains 40% of recycled material in the handle, while Reach Essencial Johnson&Johnson® (REJJ) toothbrush is manufactured with 100% of virgin material. This work also evaluated the different results of studies with different system boundaries: cradle to gate and cradle to grave. The Life Cycle impact assessment (LCIA) was conducted according to EDIP97 method. When just the toothbrush handle was compared (cradle to gate), the results varied according to the allocation criteria adopted. EREJJ did not present lower impact when the allocation was applied according to Wenzel et al (1997). When the allocation was applied according to ILCD Handbook (2010), EREJJ presented impact reduction for: global warming (39%), non-renewable (41%) and renewable (41%) resources consumption. In the cradle to grave study, the allocation approach showed little interference on the final data. The normalized data showed that the EREJJ presents 44% less impact when compared to REJJ, regardless the allocation criteria. In the conditions of this study, the allocation criteria showed less interference on the final results in the study with broader system boundaries.

Key words: Comparative LCA, allocation criteria, system boundaries, toothbrush.

1.

Introduction

Several companies recognize that good environmental performance is a critical factor for their success in the future. In order to reduce their environmental impact, the companies implement treatment actions, cleaner technologies and product modifications (Nielsen and Wenzel 2002). There is an increasing awareness about the importance of environmental protection and the potential impacts associated to products, both in their manufacture and use phases. As a consequence there is an increasing interest to develop methods to enhance comprehension and reduce these impacts. One technique broadly applied with this objective is the Life Cycle Assessment (LCA), since it allows identifying which stage of the life cycle has greater contribution to the environmental impact related to a product (ABNT 2008). 434


Considering the importance of LCA, it is fundamental to understand its applications and limitations. Life Cycle Assessment (LCA) is standardized in accordance with ISO 14040 and 14044 references. However, there are several practices (methods, tools, techniques) and application ways. LCA is one among various techniques for environmental management (for example: risk assessment, environmental performance evaluation, environmental audit and environmental impact evaluation) and may not be the best technique for all situations (ABNT 2008). The objective of the study was to evaluate the impact of different allocation methods (in case of recycled material) and system boundaries on the results and consequently on the conclusion of the comparative study. The study compared the environmental benefit of Eco Reach Essencial Johnson&Johnson® (EREJJ) to Reach Essencial Johnson&Johnson® (REJJ) toothbrush and toothbrush handle according to two different allocation criteria: presented by Wenzel et al. (1997) and the ILCD Handbook (2010). EREJJ toothbrush is made with 40% of pre consumption recycled material and REJJ toothbrush is made with 100% virgin material. Also, the study compared two system boundaries: cradle to gate (toothbrush handle analysis) and cradle to grave (toothbrush analysis).

2.

Method

The LCA was conducted according to ISO 14040/14044 standards and EDIP97 method to compare the environmental impacts of EREJJ to REJJ toothbrushes. Firstly, a cradle to gate study was conducted to compare the environmental impact of the toothbrush handle of the two products. In this case, the functional unit is the reference flow, established as ―1 ton of material to produce toothbrush handles‖ and the phases of the study are Raw Materials, Transportation and Handle Manufacture. The potential impact categories selected were: Global Warming and Resource Consumption (non renewable, renewable and energy). This simplified study was conducted to verify the environmental benefit of using recycled material in the toothbrush handle. Then the cradle to grave LCA compared both toothbrushes. The function of the systems was ―oral hygiene by using toothbrush three times a day for three months‖ (i.e. 4 toothbrushes are used per year) and the functional unit for this study is ―to promote oral hygiene of 250 persons for 1 year through tooth brushing‖. Thereby, the reference flow for both systems was 1000 toothbrushes. This reference flow (1000 toothbrushes) was used to avoid too low values in the Inventory phase and final results. The life cycle phases included were: Raw Materials, Transportation, Toothbrush Manufacture (handle production and bristling) and End-of-Life. Since this was a comparative study, the identical phases for both systems (some production and transportation processes, Packaging and Use) were not considered. All resource consumption impact (renewable, non renewable and energy) and potential environmental impact categories listed in EDIP 97 (global warming, stratospheric ozone depletion, photochemical ozone formation, acidification, nutrient enrichment, ecotoxicity, human toxicity) were considered. To evaluate the relevance of the potential environmental impacts, the contribution of each potential impact was normalized to annual consumption using EDIP 97, since the 2003 version does not consider impacts on a worldwide scale. Primary data on formulations, material compositions, primary suppliers and their locations, and toothbrush production were used to the maximum extent possible. According to the cut-off criteria established, the environmental impacts of inputs that represented less than 5% in mass of the product system were not considered. Secondary data was used based on GaBi 4 database for polyethylene and polypropylene life cycle inventories, literature data regarding equipment energy consumption and publication with data that reflects Brazilian condition (Monteiro 2008) for diesel and hydroelectric energy life cycle inventories. The allocation procedure for recycling is necessary to quantify the impacts of the pre consumption recycled flow that occurs to produce EREJJ toothbrush. Allocation solves the multifunctionality by splitting up the amounts of the individual inputs and outputs between the co-functions according to some allocation criterion, being a property of the co-functions (ILCD 2010). The 435


allocation procedure was applied on the process that generates the pre consumption waste while manufacturing other plastic products. According to Wenzel et al. (1997), there are two different ways whereby a process can contribute to more than one function: 1) when several products, called co-products, simultaneously arise from or enter into one process and 2) in the case of recycling materials or sub-assemblies from one product. There are several variants under each of these two categories. In this study the allocation was applied considering co-products in the special case when production waste from a process is used in another product. In this case, the authors state that the environmental aspects of the elementary processes and transportation that occurs before the process that generates the waste must be allocated between the final product and the waste. Exception is made for the elementary process that originates the waste and the transportation immediately preceding this step. In these cases, the environmental aspects must be allocated only to the main product. All the inputs and outputs later must be allocated to the product that utilizes the waste. Figure 1 illustrates this case.

Oil Extraction

Transport

Refining

Naphtha cracking

Transport

Polymerization

Transport

Injection molding

Product 1 Production waste

Transport

Injection molding

Product 2

Figure 1 - Allocation criteria according to Wenzel et al. (1997) On the other hand, according to ILCD Handbook (2010), in those cases where the waste does not present market value and were during the waste treatment processes a valuable product is produced, this secondary good is a co-product of the first system and an allocation is to be applied. It is argued that all treatment processes that are necessary until the treated waste product is achieving a market value of zero are within the responsibility of the first system. This is because the waste or end-of-life product is generated by the first system, while a waste cannot per se carry any burden of treatment. Furthermore it is considered inappropriate to attribute all preceding waste treatment processes to the eventually produced secondary good. An allocation of burdens to the secondary goods can only be done at process step where a valuable secondary good is produced. In the example of Figure 2, ―Transport‖ and ―Injection molding‖ after production waste are steps where a valuable secondary good is produced. Thus, the studies were conducted with both allocation criteria in order to evaluate the impact of different allocation criteria on the final results. Oil Extraction Naphtha cracking Transport

Transport

Refining

Transport

Polymerization

Injection molding

Product 1 Production waste

Transport Transport

Injection molding

Product 2

Figure 2 - Allocation criteria according to ILCD Handbook (2010)

3.

Results and Discussions

3.1.

Comparative Study – Toothbrush Handle

The results of the comparative study (Figures 3 to 6) show that the outcomes vary according to the allocation criteria. When the allocation was applied according to Wenzel et al. (1997), the results are higher when compared to the allocation according to ILCD Handbook (2010) for all environmental categories considered in the study. When production waste from a process is used 436


in another product, Wenzel et al. (1997) state that the environmental aspects must be allocated between both products. By contrast, ILCD Handbook (2010) argues that all environmental burdens must be attributed just to the first product. Therefore, it was expected to have lower values when allocation was applied according to ILCD Handbook (2010). It is known that application of distinct allocation method give different values of cumulative environmental impact for the same material and that these impacts change at differing rates between the various methods (Nicholson 2009).

Figure 3 - Global Warming potential impact related to the product systems (toothbrush handle)

Figure 4 - Non renewable resource consumption impact related to the product systems (toothbrush handle)

Figure 5 - Renewable resource consumption impact related to the product systems (toothbrush handle)

Figure 6 - Energy consumption impact related to the product systems (toothbrush handle)

The energy consumption related to EREJJ handle is higher than the related to REJJ handle (Figure 6), regardless the allocation approach. An additional extrusion process is necessary to enable the appropriate waste incorporation into the handle. This process is essential to assure quality of the final product. The impact of this additional process is observed through the higher energy consumption: 283% higher when allocation is applied according to Wenzel et al. (1997) and 99% higher when allocation is applied according to ILCD Handbook (2010). For the other categories, EREJJ handle showed lower impact than REJJ when allocation was applied according to ILCD Handbook (2010). This evidences that, in this case, the use of recycled material in the toothbrush handle presents an environmental benefit related to global warming (39% lower), non renewable (41% lower) and renewable resource consumption (41% lower). However, when allocation was applied according to Wenzel et al. (1997), the environmental benefit was not observed, which reinforces that different allocation methods give different values and these disparities result in different conclusions.

3.2.

Comparative study – Toothbrush

In the comparative cradle to grave LCA, the outcomes varied less according to the allocation 437


criteria. Figures 7 to 10 present results of some categories evaluated in the study. For some categories (e.g. global warming and non renewable resource consumption), the impact or potential impact presented very similar values for both allocation criteria. In all categories, the process showed significantly higher contribution than the transport.

Figure 7 - Global Warming potential impact Figure 8 - Non renewable resource consumption related to the product systems (toothbrush) impact related to the product systems (toothbrush)

Figure 9 - Renewable resource consumption impact related to the product systems (toothbrush)

Figure 10 - Energy consumption impact related to the product systems (toothbrush handle)

For the same reason mentioned in the previous item, the energy consumption related to EREJJ toothbrush is higher than the related to REJJ toothbrush, regardless the allocation approach. When allocation is applied according to Wenzel et al. (1997), the energy consumption is 14 times higher and when allocation is applied according to ILCD Handbook (2010), it is 13 times higher. For all other categories, EREJJ toothbrush showed lower impact according to both allocation approaches. To evaluate the relevance of the potential environmental impacts, the contribution of each potential impact was normalized to annual consumption using EDIP 97 (Figure 11). The graphic shows that the results did not vary with the allocation approach. For both allocation criteria, EREJJ showed 44% less impact then REJJ. It is assumed for many LCA‘s that a 10% difference between the test case and the baseline case qualifies as significant (Weisbrod and Hoof 2011). Therefore, it is verified an environmental benefit of EREJJ toothbrush when compared to a toothbrush without recycled material. The normalized data shows that the allocation approach did not influence significantly the overall results in this LCA study.

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Figure 11 - Normalized data for Reach Essencial Johnson&Johnson® toothbrush vs. Eco Reach Essencial Johnson&Johnson® toothbrush

4.

Conclusion

This study performed a comparative LCA between 2 toothbrushes (EREJJ and REJJ) in order to evaluate two allocation criteria - according to Wenzel et al. (1997) and ILCD Handbook (2010) and their impact on LCA final results. EREJJ toothbrush is made with 40% of pre consumption recycled material and REJJ toothbrush is made with 100% virgin material. In the cradle to gate study, the outcomes varied according to the allocation criteria. EREJJ did not present lower impact when the allocation was applied according to Wenzel et al (1997). When the allocation was applied according to ILCD Handbook (2010), EREJJ presented impact reduction for: global warming (39%), non-renewable (41%) and renewable (41%) resources consumption. The cradle to grave results presented less variation due to the allocation criteria and the normalized data showed that the EREJJ presents 44% less impact when compared to REJJ, regardless the allocation criteria. In the conditions of this study, the allocation criteria tend to interfere less on the final results in a broader study (cradle to grave) when compared to a cradle to gate study. It is known that application of distinct allocation method give different values of cumulative environmental impact for the same material. Also, different allocation methods give different values and these disparities can result in different conclusions (Nicholson 2009). This work showed that divergent conclusion due to different allocation approach is reduced when the system boundaries is extended. It is important to emphasize that one study limitation is the lack of database with information that reflects the Brazilian reality.

5.

References

Associação Brasileira de Normas Técnicas – ABNT (2008) NBR 14040: Gestão Ambiental – Avaliação do Ciclo de Vida - Princípios e estrutura. Rio de Janeiro. Bortolin AR (2009) Avaliação do Ciclo de Vida: principais métodos e estudo comparativo entre o cesto de plástico e de inox de uma lavadora de roupa. Dissertation, São Paulo University. Coltro L (2007) Avaliação do Ciclo de Vida – ACV. In: Coltro L (org) Avaliação do Ciclo de Vida como Instrumento de Gestão, 1st edn. CETEA/ITAL, Campinas, pp 7 - 14 Hauschild M, Jeswiet J, Alting L (2005) From Life Cycle Assessment to Sustainable Production: Status and Perspectives. Annals of the CIRP 54/2. International Reference Life Cycle Data System - ILCD (2010) General guide for Life Cycle Assessment - Detailed guidance. European Union, Ispra 439


Monteiro MF (2008) Avaliação do Ciclo de Vida do Fertilizante Superfosfato Simples. Dissertation, Federal University of Bahia. Nicholson AL, Olivetti EA, Gregory JR, Field FR, Kirchain R (2009) End-of-life LAC Allocation methods: open loop recycling impacts on robustness of material selection decisions. Sustainable Systems and Technology. Paper presented at ISSST‘09. IEEE International Symposium held 18/20 May, pp 1-6 Nielsen PH, Wenzel H (2002) Integration of environmental aspects in product development: a stepwise procedure based on quantitative life cycle assessment. Journal of Cleaner Production 10:247-257 Weisbrod AV, Hoof GV, (2011) LCA-measured environmental improvements in Pampers® diapers. International Journal Life Cycle Assessment. 17:145-153 Wenzel H, Hauschild M, Alting L (1997) Environmental Assessment of Products. Volume 1: Methodology, tools and case studies in product development, 1st edn. Chapman & Hall, London

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Evaluation of the dicalcium phosphate process with a view to environmental performance improvement identification Martinho, Henrique Miguel1 Kulay, Luiz1 1 Polytechnic School of the University of Sao Paulo

e-mail: [email protected]

Abstract Dicalcium phosphate (CaHPO4.2H2O) is used in the composition of dog food, mineral salts, and other products used by the livestock sector. Nevertheless, its manufacture is not absent from causing impacts on its sourroundings. An organization within the Brazilian fertilizer sector is proposing to search for alternatives towards environmental performance improvement for its dicalcium phosphate production process. This study involves the initial stage of this initiative and deals with the elaboration of a Life Cycle Analysis (LCA) with a view to identifying potential points for the implantation of these improvements. The study revealed that phosphoric acid production and sulfur combustion – previous activity electricity cogeneration – are stages with elevated environmental compromise potential. However, only when looking from a systematic vision brought about by the LCA, was it possible to identify further, and mainly, the important influence of sulphuric acid production – in the manner currently practiced by this organization – upon the above stated processes. Based upon these results, it will thus be possible to dimension solutions that reduce the impacts brought about by such process stages, testing the environmental validity of these same actions prior to their implementation. Key words: dicalcium phosphate, animal supplement, Life Cycle Assessment, LCA, Continuous Improvement.

Introduction Considered as the main essential ingredient in the composition of products involved in the area of animal feed, dicalcium phosphate is included as a source of phosphate and calcium in dog food, mineral salts and other regularly consumed products in the livestock sector. However, its manufacture for the functions to which it is destined is not absent of bringing about impacts on the environment. This occurs not only by way of the inexorable consumption of phosphate rock – a natural resource considered by many as the strategic reserve of a nation – but also because of the demand for water, sulfur, additives, energy, other processing agents, of loses to the environment in terms of liquid effluents, gaseous emissions, solid residues, of the inevitable misuse and transformation of the soil as well as the suppression of vegetation originating from the mining activities. Characteristics such as these have motivated an important organization within the Brazilian fertilizer sector to evaluate its environmental performance within the technological route used by it in the manufacturing of dicalcium phosphate. The initiative materialized in the form of a research project conducted in conjunction with the Chemical Engineering Department of the University of Sao Paulo. The present study makes up the project‘s initial phase and deals with a Life Cycle Analysis (LCA) that looked at identifying potential points for the implementation of the above cited actions. The strictly procedural character of the analysis predisposed that the LCA technique would be applied within a focus of the type ―cradle to gate‖.

Technology for obtaining dicalcium phosphate Obtaining dicalcium phosphate can be structured in accordance with two groups of processes: the mineral sector and chemical transformations. The mineral sector consists of the operations of 441


washing, crushing and the concentration of the mineral Apatite. For their part, the chemical transformations bring together the manufacturing processes of sulphuric acid and phosphoric acid, as well as the making of dicalcium phosphate itself. The washing of the mineral deposit is done in the open air, the stage of its dismantling having been carried out by explosions in various detonation networks. The sterile material is transported to deposit mounds. The mineral – with a theoretical phosphorus average of 4.5%ww P2O5 – goes from there to the crushing plant, where it will be crushed and classified. That accepted by screening feeds the milling unit, already in the concentration plant (CETEM, 2004). The concentration is based on the use of unitary operations of separation in order to separate the minerals Calcite and Magnetite from the Apatite, of interest to the process (CETEM, 2005). The chemical sector begins with the manufacture of sulphuric acid, starting from the combustion of sulfur in the presence of excess dry air. Such a transformation brings about not only sulfur dioxide (SO2) – an essential intermediate in the production of H2SO4 – but also generates a high pressure vapor, from which electricity is generated in order to attend to the demand of a part of the complex by cogeneration. The H2SO4 reacts with the concentrated Apatite under controlled temperature conditions with a view to phosphoric acid production. From the process some contaminated calcium sulfate, know within the sector as phosphogypsum, is obtained. Although of lesser added value, this byproduct is generated in the massive proportion of 4.8:1 in relation to H3PO4. The final process stage consists in the production of the desired product itself, dicalcium phosphate. This occurs through the intermediate reaction between H3PO4 and calcium carbonate, CaCO3. After drying in industrial furnaces, the dicalcium phosphate is sent for dispatch.

The LCA of dicalcium phosphate production This LCA study was carried out starting from the theoretical registration described by the norms ABNT NBR ISO 14040 (2009) and 14044 (2009). Thus, in what is referred to as Objectives Definition the initiative proposes to identify opportunities for environmental performance improvements in the specific production process of dicalcium phosphate. As to the Scope Definition the following requisites were established: Product System: dicalcium phosphate – a product based on phosphorus and calcium – commercialized within the market in the forms of micro-granulated P18 and P20, P18 powder and micro-granulated MCPD. Function: to produce micro-granulated P18 dicalcium phosphate. Functional Unit: to produce 1.0 t of micro-granulated P18 dicalcium phosphate. Frontiers of Product System: the product system under analysis considered the elementary processes of phosphate rock treatment – which are made up of the washing, crushing and classification operations –; obtaining the phosphate concentrate; the importing of sulfur; sulphuric acid and phosphoric acid production; the extraction of limestone (calcium carbonate) and the production of dicalcium phosphate. To these were added the generation of utilities – industrial water treatment, boiler water and effluents and the production of electricity by cogeneration –; the diverse internal transportation that occurs during the process; and the production and transport of electricity acquired from the Brazilian grid. Product system is described in Figure 1. Exclusion Criteria: excluded from the LCA were the environmental loads whose accumulated contributions of mass and energy presented values lower than the level of 1%. Loads whose environmental relevance had been considered negligible, in terms of the instructions defined in ABNT NBR ISO 14044 (2009), were also excluded. Data sources: the consumption of resources and the generation of residues to the environment, directly related to the manufacture of dicalcium phosphate, were modeled starting from primary data collected for the study‘s objective. The same thing occurred with the environmental loads associated with the transportation of inputs internal to the unit, as well as of the industrial utilities production. For other production system elements – the cases of production and transport of sulfur and of electrical energy acquired from the grid – secondary data was used.

442


Figure 1: Dicalcium phosphate production manufacturing system

Data Quality: in what is referred to as Temporal Dimension it was decided – for primary and secondary data – to use a continuous historical series defined during the twelve months of 2011. In terms of Geographical Dimension, The State of Sao Paulo was considered – the region in which the dicalcium phosphate manufacturing unit is installed. For the specific case of sulfur, the productive regions within countries from which importation occurs, were identified, namely: Germany, Canada, United Arab Emirates, the United States, Italy, Qatar and Russia, Still on the case of this raw material, the product system of the mining processes – via the Frasch Process; the burning of Pyrite; the de-sulfurization of crude oil and natural gas, regularly used by suppliers for obtaining it, were integrated. Finally, as to the Technological Dimension, the sequencing of the operations laid out in the productive processing description (Figure 1) were observed, considering the whole production studied as being of the formulation dicalcium phosphate P18 microgranulate. Allocation: the energy content as the criteria of allocation between vapor and H2SO4 for the case of sulphuric acid production was applied. In whatever other situation, mass criteria was employed. Impact evaluation Category and Models: in order to obtain an environmental impact profile generated by a group of analytical indicators, the ReCiPe Midpoint (H) – version 1.07 method was selected. For the environmental profile, all of the impact categories of the model were adopted, apart from: Marine Eutrophication; Marine Ecotoxicity; Ionization Radiation; Urban Land Occupation; Natural Land Transformation; and Metal Depletion (GOEDKOOP et al. 2012). The fact that the LCA study had been elaborated in order to identify opportunities for improved environmental performance for a process specific to dicalcium phosphate production required that additional premises to the requirements previously announced for the modeling of the product system were also established. Some of these considerations were the following: a) For the cases in which primary data had not been available, estimates by way of the balances of material and energy, carried out starting from complementary data, were performed; b) The unavailability of the means of particulate material emissions determined in rock washing, preconditioned the use of the specific Ecoinvent database (ALTHAUS et al, 2007); c) The consumption of air for sulfur combustion in sulphuric acid production, of 2.97kg / t. H2SO4 was obtained from Lutgens & Tarbuck (1995);

443


d) Even with mass cumulative contributions lower than 1% in their respective elementary processes, collectors, depressors and catalyzers were considered, for the effect of the elaboration of the LCA, at the level of elementary entrance flows; e) The cogeneration unit operates in accordance with the Rankine Cycle. The rate of thermal energy conversion into electrical energy in the turbine was estimated at 70%. The boiler vapor extracted from the same equipment as dry saturated at 0.1 bar pressure, was considered. The Thermodynamic properties for steam were obtained from Moran & Shapiro (2006); f) The removal of 95% of fluorides and phosphates in the effluent treatment station of the dicalcium phosphate processing unit were allowed for; g) The model elaborated for the sulfur transportation considered rail transportation from the obtaining site to the port of origin. Also, transoceanic transport occurring by fright ship was considered. In all cases real and registered itineraries were used. Transport between Santos port and the industrial unit was modeled by road travel and at a distance of 225 km; h) The discarding of inert solid waste from the process occurred via a landfill. The environmental loads generated by this action were modeled by databases for this scenario (DOKA, 2009); i) Energy emissions in the form of noise and vibrations were not contemplated in the study; j) Environmental loads associated with capital goods involved in the process were not considered.

Results and Discussion The evaluation of the environmental performance for dicalcium phosphate production was modeled with the help of the software SimaPro 7.0 – version 7.3 (Pre Consultants, 2010). Table 1 shows the totalized results of performance for the process in question, as well as the individual percentage contributions of the elementary processes that constitute the product system. As to Climate Change, the main contributions (56.7%) occurred with electricity, acquired from a concessionaire, by virtue of the CO2 and CH4 emissions in hydroelectric reservoirs, as well as from CO2 in the burning of natural gas and fuel oil in thermoelectric plants, important contribution modes for the national energy matrix. In terms of Freshwater Eutrophication the most significant intake originated from the loss of phosphates in the production of H3PO4. The important impacts brought about by the system in terms of Ozone Depletion were considered to be residual. The results observed in terms of Terrestrial Acidification were, to a certain extent, expected by virtue of emissions, even when residual, of SO 2 and SO3 brought about by the Double–Absorption and Double-Contact (DA/DC) process during H2SO4 production. As it is possible to observe in Table 1, this influence is reflected in the H 3PO4 production and in electricity cogeneration. In terms of Human Toxicity and Freshwater Ecotoxicity, the following stood out: loses of metals and organic compounds in the cultivation of timber used in the process as a source of thermal energy in rock concentration and in dicalcium phosphate manufacture; sulfur and catalyzer sludge in H2SO4 production – which is reflected, once again, in steam cogeneration; and discard of metals and pesticides associated with the national energy matrix, starting from the burning of biomass and charcoal. The main contributions in terms of Photochemical Oxidant Formation came from the emission of NOx that occurred in successive transport operations for the importing of sulfur. Once more this performance was notable in the H3PO4 production and the steam cogeneration; together, elementary processes account for exactly 74.8% of the product system impacts in this category. It also happened that these are the causes for the same elementary processes being pointed to as the main contributors for Particle Matter Formation. The use of pesticides in the cultivation of wood for energy production, justifies the prevalence of this elementary process (55.84%) over its homologues in terms of intakes for Terrestrial Ecotoxicity.

444


Table 1 – Environmental impact profile for the dicalcium phosphate process

As might have been imagined beforehand, it also falls upon the generation of thermal energy via the burning of chips intake, almost completely (96.29%), in terms of Agricultural Land Occupation. The most expressive contributions in terms of Water Depletion occurred starting from the consumption of water in humid milling; in phosphate rock concentration and in the production of H3PO4. Together these totaled 66.15% of all of the quantified impacts for the category in question. In terms of Fossil Depletion, the consumption of diesel oil for raw material transportation was outstanding; of natural gas for the dicalcium phosphate process; as well as, for these same petroleum derivatives, their usage in the national energy matrix.

Proposal for alternative improvements The study allowed for the identification of the phosphoric acid and electricity cogeneration processes as the stages with the greatest impact in obtaining dicalcium phosphate. Together with the electricity acquired from the concessionaire, such elementary processes always figured amongst the three principal contributors for the product system‘s environmental impacts in twelve of the thirteen categories analyzed. However, the common influence upon both processes for the production of sulphuric acid was highlighted. In this context, the importation of sulfur – whose logistic reformulation could be carried out, taking the environmental variable as a benchmark – would become the target of potential improvement actions, as well as the losses of SOx to the atmosphere. If such effects were to be damped down, one could then think of increasing cogeneration, already in operation at the unit, to levels that would allow for no longer having dependence on energy supplied by the Brazilian grid. Such non-compatibility must occur, only and merely, after taking care of the rationalization of the raw materials of the process itself.

Conclusions The realization of the LCA study was clearly effective as to the identification of potential improvement points involving environmental performance in the dicalcium phosphate process. This, not just from the fact of starting from the application of the technique, but also by making it possible to identify the profile of the more relevant impact processes: phosphoric acid production; and importation of sulfur. In present study, the main virtue of the LCA was to allow for the identification of the cause of these impacts, by processing of sulphuric acid, which had been acting behind both processes, influencing them in a negative manner. Based upon these results, it will now be possible to dimension solutions that reduce the impacts brought about in such stages of the process, testing the environmental validity of these same actions, before their implementation. These are precisely the next steps of the project into which this initiative is inserted.

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References ABNT – Associação Brasileira de Normas Técnicas. NBR ISO 14.040 - Gestão ambiental Avaliação do ciclo de vida - Princípios e estrutura. 2009. Rio de Janeiro. ________. NBR 14.044 - Gestão ambiental - Avaliação do ciclo de vida - Requisitos e orientações. 2009. Rio de Janeiro. ALTHAUS, H-J.; HISCHIER, R.; OSSES, M.: Life Cycle Inventories of Chemicals. Ecoinvent report. No. 08. Ecoinvent Centre. Dübendorf. 2007. pp 541- 542. CETEM – Centro de Tecnologia Mineral. Introdução ao Tratamento de Minérios. In: Tratamento de Minérios. 4ª. Ed. 2004. Rio de Janeiro. pg. 3-16 ________. Britagem. In: Tratamento de Minérios. 4ª. Ed. 2004. Rio de Janeiro. pp.113-194. ________. Fosfatos. In: Tratamento de Minérios. 5ª. Ed. 2005. Rio de Janeiro. pp.141-171. DOKA, G. Life Cycle Inventories of Waste Treatment Services. Part II – Landfills – Underground deposits – Landfarming. Ecoinvent report. No. 13. Ecoinvent Centre. Dübendorf. 2009. 140pg. GOEDKOOP, M., HEIJUNGS, R., HUIJBREGTS, M., DE SCHRYVER, A., STRUIJS J.: Description of the ReCiPe methodology for Life Assessment Impact Assessment. 2012. retrieved from http://www.lcia-recipe.net LUTGENS, F. K.; TARBUCK, E.J.: The Atmosphere. 1995. Prentice Hall, 6th ed. pp14-17. MORAN, M.J.; SHAPIRO, H.N.: Fundamentals of engineering Thermodynamics. 5th ed. 2006. John Wiley & Sons, Inc. pp 770 – 772. PRé Consultants. SimaPro, 7.0 – v. 7.3. 2010. Amersfoort, Netherlands.

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LCA-based comparison of different scenarios of the application of a novel ceramic nanofiltration membrane in the pulp industry Florian Gehring* – Jan Paul Lindner+ – Tabea Beck* – Hannes Krieg* – Robert Ilg* * Dept. Life Cycle Engineering (GaBi), Chair of Building Physics, University of Stuttgart, Wankelstrasse 5, 70563 Stuttgart, Germany

+49-711-9703173 [email protected] URL: www.lbp-gabi.de +

Dept. Life Cycle Engineering (GaBi) Fraunhofer IBP, Wankelstrasse 5, 70563 Stuttgart, Germany

Abstract One of the most important basic needs of human, animal, and plant life is water. In Germany, water consumption in industry was reduced in the last years by process- and productionintegrated recycling of water. One challenge is that harmful substances and contaminants can accumulate in the water circuit. These substances can disturb production processes and need to be removed. As common filters are often not resistant enough to particularly corrosive media, new filters are being developed. The project NanoMembrane, supported by the German Bundesministerium für Bildung und Forschung36 (BMBF), is aimed at the development of ceramic nanofiltration membranes with a very small pore size in order to profit from the most novel technology. Furthermore, it determines the potential for sustainable development for various industrial sectors through the application of improved waste water treatment systems. One of the industries under assessment is the pulp & paper industry. Within this sector, potential applications of the newly developed membrane are being analyzed. The new membrane is more pH and temperature resistant than other commonly used membranes, so it is a suitable alternative for treating highly contaminated waste water streams. In the pulp industry one of those streams is bleaching filtrate, which currently can only be partially recycled. Through the filter system using the novel ceramic membrane, more water circuits can be closed. On the one hand it is possible to recycle a larger share of water due to the lower contamination of the generated permeate. On the other hand there are new application possibilities for the treated stream. An LCA model is developed, which allows creating a representative comparison between different scenarios and the current state of the art. At places where the permeate could be used, the temperature and the load of chemical oxygen demand have to be met. There are two options for the utilization of the retentate; discharge to waste water treatment or evaporation and subsequently incineration with energy recovery. The comparison of the scenarios of retentate utilization shows significant differences in environmental impacts. The influence of the evaporation option depends on the perspective of the viewer, because emissions released in the generation of low pressure steam can be allocated differently. The comparison also confirms that not every scenario has a positive influence on the considered impact categories. Key words: Nanomembrane, Water, Recycling, Filtration

36

Federal Ministry for Education and Research 447


Abbrevations: wtp, water treatment plant; wwtp, waste water treatment plant;

Introduction The production of pulp is a water intensive process. Despite the considerable water use reduction in the last 50 years, water consumption amounts to an avarage of 45 litres per 1 kg pulp [1]. According to market data, the pulp demand will increase to the year 2025 at an avarage 1.5 % per year. This means that the pulp production amount increases from 150 million to 170 million tons [2]. Pulp is predominantly used to produce paper, carton, and tissue products. Because of the higher pulp demand the water consumption increases in the next years. Process- and production integrated water recycling reduced the fresh water consumption in the last years. An important part was the the multiple water usage and the circuitry of the originating waste water. Contaminants accumulate continuously in the water circuit which limits the water return. The Limit is given by boundary conditions like the chemical oxygen demand (COD). With contemporary filtration technology the contaminants could be removed, but the extreme temperature and the high pHvalue attack and destroy the filter coating. The development of resistant filters continues. The NanoMembrane project is supported by the German Bundesministerium für Bildung und Forschung and aimed at the development of a novel ceramic nanofiltration membrane in order to profit from the most novel technology. This technology enables more water to be circulated. The strenght of the novel membrane is the small pore size and the ceramic coating, which is resistent against aggressive waste water. The technology allows to reduce both freshwater use and wastewater generation. Parallel to the membrane devolopment ecological impacts of the application of the membrane are reviewed and assessed.

Goal and scope One scope in the project is the assessment of the environmental impacts from using nanofiltraion in the treatment of wastewater from pulp production. A model is developed which allowed a representive comparison between the current production and the considered scenarios. The waste water stream (feed) is led to the membrane which separates the main stream into permeate (filtrate) and retentate (concentrate). Picture 1 shows a filtration process and the generated streams (permeate and retentate). Figure 1: Schematic structure of a nanofiltration process [3] There are various recovery possibilities for both streams. The filtrated permeate has a lower COD load than the currently recycled waste water and enables a higher circulation rate. Boundary conditions for the circulation are given by the COD load. For the retentate recycling two options are compared. On the one hand the discharge to the waste water treatment plant and on the other modul pump permeate

feed

membrane

hand the evaporation and subsequent incineration of suspended solids.

448


Life cycle assessment The model shows the conditioning of accrue bleaching water which is generated by the production of one (metric) ton of pulp. The system boundary includes all processes which have an influence on the considered scenarios. Power and steam production is given special attention because of the specific on-site production. Power and steam is produced from black liquor and bark incineration. Allocation of emissions is quite complex and difficult. A represetantive approach is to allocate the emissions based on exergy content. Data used in this model are supplied by Zellstoff Stendal GmbH.

Scenarios The considered scenarios differ in concentrate (retentate) utilisation. Overall, there are three scenarios which are compared among each other as well as against the current process. The filtrate (permeate) can be used for three processes. Two different recovery and utilisation options are possible for the concentrate (retentate). In scenario2 the generated retentate is piped to the waste water treatment plant. In the scenarios3r and 3a the retentate is evaporated, the solids are combusted, and the emerged condensate is either recycled (3r) or disposed (3ª).

Results In this study the impact categories global warming potential, eutrophication potential, acidification potential, photochemical ozone creation potential, primary energy demand (fossil and regenerative) are assessed. In this paper, only the global warming potential (GWP) is presented. In Figure 2 shows the GWP in kg CO2 equivalent). It shows the impact of the different scenarios in this category.

Global warming potential (GWP)

kg CO2-equivalent per tone pulp

120 100

wtp (reverse osmosis) 80

incineration energy nanomembrane

60

steam generation 40

wwtp (high contaminated) 20

wwtp (low contaminated) wwtp (contaminated)

0

current-state

scenario2

scenario3r

scenario3a

Figure 2: Global warming potential of the different scenarios [4] In the current state more kg CO2 equivalent is generated than in all the other considered scenarios. Scenario2 has the lowest influence on this category followed by scenario3r and 3a. A detailed look at the efficiency of the different permeate recycling options yields the next diagram which shows a feed variation. Feed Variation means that the waste water stream to the membrane increased step by step. Scenario2 has the lowest ecological impacts and is used as a reference.

449


Feed variation (GWP) 100% 80% 60% 40% 20% 0% 0%

20%

40%

60%

80%

current-state

100%

scenario2

Figure 3: Graph of the feed variation between the current state and scenario2 [4] The graph shows the differen efficiencies of the permeate recycling options. Furthermore, it is possible to reduce fresh water consumption and waste water production. Figure 4 shows the water reduction of the considered scenarios.

Fresh and waste water balance

Liter per kilogram pulp

40 35

34,5 31,4

31,4

30,4

30 25

23,0 19,9

20

19,3

19,7

scenario3r

scenario3a

15 10 5 0

current-state

scenario2 fresh water

waste water

Figure 4: Fresh water consumption and waste water production of the different scenarios [4] Each scenario has a lower fresh water consumption and waste water production than the current state. The diagram shows that scenario3r has the lowest water balance of all. Overall up to 4.1 liters fresh water (11.8%) and 3.7 liters waste water (16.8%) could be saved.

Summary and outlook In this study a life cycle model is developed which allowed the comparison of different scenarios to their environmental impacts. It would exemplarily demonstrate that a decreasing water use does not automatically have a positive environmental effect. Furthermore the results of the different impact categories do not correlate with each other. Just in this aspect it is important to quantify tradeoffs. The research and development in the frame of the project goes on. This means currently unclear data in the ongoing progress could be obtained and included. The study shows in which direction the application of nanofiltration in the pulp & paper industry can go. [1] European Commission (pub.) (2011): Reference Document on Best Available Techniques in the Pulp and Paper Industry; Brussels (Belgium). [2] Andritz (2010): Die Welt von Andritz Pulp and Paper, Geschäftsbericht 2010; Graz (Austria). [3] Menzel, U. (2009/2010): Industrielle Wassertchnologie, lecture note; Institute for Sanitary Engineering, Water Quality and Solid Waste Management, University of Stuttgart (Germany). 450


[4] Gehring, F. (2012): LCA based consideration of the application of a novel ceramic nanofiltration membrane in the pulp and paper industry; diploma thesis; LBP-GaBi, Stuttgart (Germany).

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Allocation in Brazilian milk production: a case study Cristiane Maria de Léis1*,2 – Christel Cederberg2 –Airton Spies3 – Sebastião Roberto Soares4. 1*4

Universidade Federal de Santa Catarina, Programa de Pós Graduação em Engenharia Ambiental,

Campus Universitário Reitor João David Ferreira Lima, Bairro Trindade, 88040-970, Florianópolis/SC, Brazil. 2

SIK- The Swedish Institute for Food and Biotechnology, P.O. Box 5401, 40229, Gothenburg, Sweden

3

EPAGRI/CEPA, Rod. Admar Gonzaga, 1347, 88034901, Florianópolis, Brazil.

[email protected]/ www.ciclodevida.ufsc.br

Abstract The purpose of this study was to compare different allocation methods of milk and meat in Life Cycle Assessment (LCA) of Brazilian milk production. Data were collected for two farming seasons (2008/2009 and 2009/2010) from three dairy farms in South of Brazil, one with a confined feedlot system, one semi-confined (including some grazing) and one pasture-based grazing system. Four allocation methods for milk and meat were tested: economic, physical, protein and mass. When using economic allocation, milk in the semi-confined system was allocated with the largest environmental impacts (94% milk, 6% meat as by-product), while when applying physical allocation the environmental impact allocated to milk was greater for confined system (98% to milk and 2% to meat). The protein allocation was similar in the three system studied with an average of 94% to milk and 6% to meat. The mass allocation was also similar between the systems, with an average of 99% to milk and 1% to meat. Physical allocation between milk and meat is prioritized according to International Dairy Federation (IDF, 2010) since it is based on energy feed input to the dairy system and reflecting the energy feed needed for milk and meat byproducts respectively. IDF´s proposal for physical allocation factor is 85% of environmental impacts attribute to milk and similar factors are used in research in Sweden. This is lower than factors calculated in this case study. In Europe, there are more precise data on dairy cattle´s feed intake and meat production by dairy cattle. The lack of these data makes it difficult to come to the same allocation factors in LCA case studies of Brazilian milk. One explanation for this can be the scale and large regional variations in Brazilian dairy and beef production as well as lack of availability of high-quality input data. There are various ways to handle co-products, some more pragmatic, others more scientific methods, but there is no single common or established method. If we use the system expansion the consequences of a change always is analyzed. In research conducted in Sweden, about 63%-76% of the emissions were attributed directly to milk when the system expansion was used, reducing the emission from milk. The choice of a allocation method influences the final results about the contribution of milk for the environmental impact and more studies focusing on joint analysis of milk and meat are necessary for Brazilian production. Key words: milk, allocation, Brazil, environmental impacts.

Introduction The expansion of new areas has contributed to increase Brazilian milk production, but the main factor responsible for the growth of production is increased productivity (MASSUDA et al. 2010). According this authors a characteristic of milk production in Brazil is the heterogeneity of production systems, because of the climate and soil conditions. The chain productive of milk is more important of brazilian agroindustrial complex (CARVALHO et al. 2003). Dairy herds produce a mix of goods and services that cannot easily be disaggregated into individual processes (GERBER et al. 2010). 452


The available date about environmental impacts from milk production are studies from Europe an few studies has been made in others countries, but the information where the environmental impact occur are very important (IDF, 2009). The according Xavier and Caldeira-Pires (2004) is need studies about LCA in the farms of Brazil, that representative of the various types of existing production systems. However, all milk production systems generate more than one functional output:milk and meat, from culled cows and calves (CASEY and HOLDEN, 2005). The allocation method used for distributing the environmental impacts between the main product and by-products (NBR ISO 14044 2009) can be significant on the final results (FLYSJÖ et al. 2011).

Methods Data were collected for two farming seasons (2008/2009 and 2009/2010) from three dairy farms in South of Brazil, one with a confined feedlot system, one semi-confined (including some grazing) and one pasture-based grazing system and was using a standardized method of Life Cycle Assessment (LCA) NBR ISO 14040 (2009) and NBR ISO 14044 (2009). The confined feedlot systems is located in north central State Paraná, in the Mandaguari city, total area of farm is 48.4ha, whith 17ha are busy with production systems. The climate is tropical and the annual average temperature isn´t more than 20°C. The semi-confined system is localized in the Porto Amazonas city and 96km from capital State Curitiba. The total area of 51.39 ha, of which 29.98 ha is busy by production systems. The climate is humid and the annual average temperature is less than 26°C. The localization of pasture system is in the middle western State Santa Catarina in Campos Novos city, in southern Brazil. The total area of the dairy farm is 219 ha, when 161 ha of these is destined for milk production. The climate is Cfa and Cfb is subtropical according to the Köppen classification. The average annual temperature is 15°C to 19°C. The lactation period in Brazil varies of 290 to 305 days and for this study was used 305 days. The replacement rate is about 25% and heifers start milking at an average age 26 months. In each farm the average cow weight is different, but the average of all farms studied was about 600 kg. The life time cow is about 6 years. Four allocation methods for milk and meat were tested: economic, physical, protein and mass. The analyse economic allocation was according Cederberg and Flysjö (2004) and the information about price/litre and price/arroba meat are from Departament of Agriculture of Paraná for confined feedlot and semi confined system and from Departament of Agriculture of Santa Catarina State for the pasture system. Boths prices were of agricultural year studied. Physical allocation between milk and meat was prioritized according to the International Dairy Federation (IDF 2010) since it is based on energy feed input to the dairy system and reflecting the energy feed needed for milk and meat by-products respectively. The protein allocation was based on edible protein in milk and meat (GERBER et al. 2010). The amount of protein in meat is about 20%, according Flysjö et al (2011). Mass allocation is performes based on mass, the total weight of milk and live weight of culled dairy cow and surplus calves, that leave the farm gate (FLYSJÖ et al. 2011).

Results When using economic allocation, milk in the semi-confined system was allocated with the largest environmental impacts with 94% milk and 6% meat as by-product, while when applying physical allocation the environmental impact allocated to milk was greater for confined system with 98% to milk and 2% to meat. The protein allocation was similar in the three system studied with an average of 94% to milk and 6% to meat. The mass allocation was also similar between the systems, with an average of 99% to milk and 1% to meat. 453


The IDF (2010) proposal for physical allocation factor is 85% of environmental impacts attribute to milk and similar factors are used in research in Sweden. This is lower than factors calculated in this case study. In Europe, there are more precise data on dairy cattle´s feed intake and meat production by dairy cattle. The lack of these data makes it difficult to come to the same allocation factors in LCA case studies of Brazilian milk. One explanation for this can be the scale and large regional variations in Brazilian dairy and beef production as well as lack of availability of high-quality input data. There are various ways to handle co-products, some more pragmatic, others more scientific methods, but there is no single common or established method. If we use the system expansion the consequences of a change always is analyzed. This is possible when the level of the digestibility of the feed and productivity per cow per year is higher. In this case is the contribution to environmental impact will be lower for the dairy system. In research conducted in Sweden, about 63%-76% of the emissions were attributed directly to milk when the system expansion was used (FLYSJÖ et al. 2011), reducing the emission from milk. These studies showed a strong relation between the dairy and meat systems.

Conclusion The choice of a allocation method influences the final results about the contribution of milk for the environmental impact and more studies focusing on joint analysis of milk and meat are necessary for Brazilian production.

Acknowledgements The authors thank the Brazilian Science and Technology National Council (CNPq) for financially supporting this research and scholarship (Process 143311/2009-3) and and Coordination of Improvement of High Education Personnel for scholarship doctoral ―sandwich‖ (CAPES/Brazil Process 2410-11-7). We would like to thank the Department Sustainable Food Production of The Swedish Institute for Food and Biotechnology (SIK) and Universidade Federal de Santa Catarina (UFSC/Brazil).

References Carvalho LA, Novaes LP, Gomes AT, Miranda JEC, Ribeiro ACCL (2003): Sistema de producao de leite (Zona da Mata Atlantica). Embrapa Gado de Leite. Sistemas de Produção. 1. ISSN 1678314X. Casey JW, Holden NM (2005): Analysis of greenhouse gas emissions from the average Irish milk production system. Agricultural Systems, 86: 97-114 Cederberg C, Flysjö A (2004): Life Cycle Inventory of 23 Dairy Farms in South-Western Sweden. SIK - Report Swedish Institute for Food and Biotechnology. 728: 63p Flysjö A, Cederberg C, Henriksson M, Ledgard S (2011): How does co-product handling affect the carbon footprint of milk? Case study of milk production in New Zealand and Sweden. Int J Life Cycle Assess 16:420–430 Gerber P, Vellinga T, Opio C, Henderson B, Steinfeld H (2010): Greenhouse Gas Emissions from the Dairy Sector, A Life Cycle Assessment. FAO Food and Agriculture Organisation of the United Nations, Rome. 98p IDF (2009): Environmental/ ecological impact of the dairy sector: literature review on dairy products for an inventory of key issues list of environmental initiatives and influences on the dairy sector. Bulletin N° 436/2009. IDF (2010): A Common Carbon Footprint for Dairy, The IDF Guide to Standard Lifecycle Assessment Methodology for the Dairy Sector. Bulletin N° 445/2010 454


Massuda EM, Alves AF, Parré JL, Santos GT (2010): Panorama da cadeia produtiva do leite no Brasil. In: Santos GT, Massuda EM, Kazama DC, Jobim CC, Branco AF Bovinocultura leiteira: bases zootécnicas, fisiológicas e de produção. Maringá: Eduem. pp 9-25 NBR ISO 14040 (2009): Avaliação do Ciclo de Vida: Princípios e Estrutura. Associação Brasileira de Normas Técnicas, 21. Rio de Janeiro NBR ISO 14044 (2009): Gestão Ambiental: Avaliação do Ciclo de Vida: Requisitos e Orientações. Associação Brasileira de Normas Técnicas, 46. Rio de Janeiro Xavier JH, CALDEIRA-PIRES A (2004): Uso potencial da Análise de Ciclo de Vida de Produtos (ACV) para a caracterização de impactos ambientais na agricultura. Cadernos de Cência e Tecnologia, 21: 311-341

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Importance of dry matter intake on environmental impacts of Brazilian milk production: a case study Cristiane Maria de Léis1*,2 – Christel Cederberg2 – Clandio Favarini Ruviaro3– Airton Spies4 – Sebastião Roberto Soares5. 1*,5

Universidade Federal de Santa Catarina, Programa de Pós Graduação em Engenharia Ambiental,

Campus Universitário Reitor João David Ferreira Lima, Bairro Trindade, 88040-970, Florianópolis/SC, Brazil. 2

3

SIK- The Swedish Institute for Food and Biotechnology, P.O. Box 5401, 40229, Gothenburg, Sweden. Universidade Federal do Rio Grande do Sul, Centro de Estudos e Pesquisas em Agronegócios (Cepan),

Porto Alegre e RS e Brazil. 4

EPAGRI/CEPA, Rod. Admar Gonzaga, 1347, 88034901, Florianópolis, Brazil.

[email protected]/ www.ciclodevida.ufsc.br

Abstract The purpose of this study was to assess how feed intake by dairy cows affects the environmental impacts of milk production in South of Brazil. The study analysed three farms with specific production systems: a confined feedlot system, a semi-confined system (including some grazing) and a pasture-based grazing system. Two farming seasons (2008/2009 and 2009/2010) were studied. The confined feedlot dairy farm had 37 dairy cows producing 7668 kg Energy Corrected Milk (ECM) per cow/year and an area of 48 ha that was 35% used for milk production. The farm with the semi-confined system had 91 dairy cows with 7325 kg ECM per cow/year and area of 51 ha of which 58% was used for milk production. The farm with pasture-based production system had 178 dairy cows producing 5306 kg ECM per cow/year and area of 219 ha of which 74% was used for milk production. Data on the annual amount of feed intake was collected separately at each farm and analysed and presented as feed intake (dry matter, energy, protein) per kg milk. The most important differences between the systems were dry matter intake from pasture and concentrate feed as the confined and semi-confined systems used some co-products of other agricultural products. Data were adjusted according to the cows´ milk production capacity and body weight per cow. The annual feed intake as dry matter (DMI) per cow was estimated at 6335 kg for the confined system, 5628 kg for the semi-confined and 4657 kg for the pasture-based system, respectively and this corresponded to a feed conversion efficiency (kg milk/kg DMI) as 0.83; 0.77 and 0.88 for confined, semi-confined and pasture system, respectively. The feed conversion efficiency estimated in this study was lower than found in research of European milk production and this has an important and direct influence on the environmental impacts, e.g. emissions of greenhouse gases. Others studies in Scandinavian countries reported that the key to performance indicator for predicting reductions emission of greenhouse gases is milk and feed production and feed conversion efficiency (ECM/DMI). Other actions towards grassland improvement, silage quality, feed cultivation, feed digestibility, genetic potential, as well as the correct estimates of the amount of feed consumption can influence the results of emissions per kg milk produced. Therefore, the precise farm-records are critical to estimate the contribution of milk production to global warming and also others impacts categories in LCA. Key words: milk production, dry matter intake, environmental impacts, Brazil.

456


Introduction The Brazilian milk production represents about 4.8% of worldwide milk production (IDF 2010). The climate and soil conditions of Brazil allow the adaptation of activity the regional peculiarities, observing the existence of several production systems (MASSUDA et al. 2010). A characteristic of milk production in Brazil is the heterogeneity of production systems (MARQUES 2003; MASSUDA et al. 2010), which difficulty of accurate information. The expansion of news areas has contributed for increase production and is the main responsible factor by the production growth (MASSUDA et al. 2010). The factors main for the determinants of milk production are the amounts of metabolisable energy and protein consumed by the cows and the partition of these nutrients between maintenance, milk production, pregnancy, growth, tissue repletion in later lactation, walking and grazing (BEEVER and DOYLE 2007). Feed conversion efficiency (ECM/DMI) can be a valuable indicator of feeding system performance (HENRIKSSON et al. 2011; BEEVER and DOYLE 2007). However, the new studies about the environmental impact of feed conversion efficiency in milk production of the subtropical region are necessary.

Methods The study analysed three farms with specific production systems: a confined feedlot system (37 dairy cows), a semi-confined system (including some grazing with 91 dairy cows) and a pasturebased grazing system (178 dairy cows). The confined feedlot systems is located in north central State Paraná, in the Mandaguari city, total area of farm is 48.4ha, whith 17ha are busy with production systems. The climate is tropical and the annual average temperature isn´t more than 20°C. The semi-confined system is localized in the Porto Amazonas city and 96km from capital State Curitiba. The total area of 51.39 ha, of which 29.98 ha is busy by production systems. The climate is humid and the annual average temperature is less than 26°C. The localization of pasture system is in the middle western State Santa Catarina in Campos Novos city, in southern Brazil. The total area of the dairy farm is 219 ha, when 161 ha of these is destined for milk production. The climate is Cfa and Cfb is subtropical according to the Köppen classification. The average annual temperature is 15°C to 19°C. The lactation period in Brazil varies of 290 to 305 days and for this study was used 305 days. The replacement rate is about 25% and heifers start milking at an average age 26 months. In each farm the average cow weight is different, but the average of all farms studied was about 600 kg. The life time cow is about 6 years. The data collect was using a standardised method of Life Cycle Assessment (LCA) NBR ISO 14040 (2009) and NBR ISO 14044 (2009). For this study was used two farming seasons (2008/2009 and 2009/2010). The calculation about Energy Correct Milk (ECM) cow/ year was used formula described by Sjaunja et al (1990) for correct fat and protein. Data on the annual amount of feed intake was collected separately at each farm and analysed and presented as feed intake (dry matter, energy, protein) per kg milk. The information about the levels of total digestible nutrients and dry matter in each food consumed in each farm was used Valadares Filho et al. (2012) using equation of NRC (2001).

Results The most important differences between the systems were dry matter intake from pasture and concentrate feed as the confined and semi-confined systems used some co-products of other agricultural products. Data were adjusted according to the cows´ milk production capacity and body weight per cow. 457


The annual feed intake as dry matter (DMI) per cow was estimated at 6335 kg for the confined system, 5628 kg for the semi-confined and 4657 kg for the pasture-based system, respectively and this corresponded to a feed conversion efficiency (kg milk/kg DMI) as 0.83; 0.77 and 0.88 for confined, semi-confined and pasture system, respectively. The feed conversion efficiency estimated in this study was lower than found in research of European milk production. Others studies in Scandinavian countries reported that the key to performance indicator for predicting reductions emission of greenhouse gases is milk and feed production and feed conversion efficiency (ECM/DMI) (FLYSJÖ et al. 2011; HENRIKSSON et al. 2011).

Conclusion The actions towards grassland improvement, silage quality, feed cultivation, feed digestibility, genetic potential, as well as the correct estimates of the amount of feed consumption can influence the results of emissions per kg milk produced. Therefore, the precise farm-records are critical to estimate the contribution of milk production to global warming and also others environmental impacts categories in LCA. The feed conversion efficiency can be a key for Brazilian milk production more effective.

Acknowledgements The authors thank the Brazilian Science and Technology National Council (CNPq) for financially supporting this research and scholarship (Process 143311/2009-3) and and Coordination of Improvement of High Education Personnel for scholarship doctoral ―sandwich‖ (CAPES/Brazil Process 2410-11-7). We would like to thank the Department Sustainable Food Production of The Swedish Institute for Food and Biotechnology (SIK) and Universidade Federal de Santa Catarina (UFSC/Brazil).

References Beever DE, Doyle PT (2007): Feed conversion efficiency as a key determinant of dairy herd performance: a review. Australian Journal of Experimental Agriculture. 47: 645-657 Flysjö A, Henriksson M, Cederberg C, Ledgard S, Englund JE (2011): The impact of various parameters on the carbon footprint of milk production in New Zealand and Sweden. Agricultural Systems 104: 459–469 Henriksson M, Flysjö A, Cederberg C, Swensson C (2011): Variation in carbon footprint of milk due to management differences between Swedish dairy farms. Animal. 5: 1474-1484 IDF (2010): World dairy situation 2010. Bulletin 446/2010 Marques DD (2003): Criação de Bovinos (7ª ed.). Belo Horizonte: CVP Consultoria Veterinária e Publicações Massuda EM, Alves AF, Parré JL, Santos GT (2010): Panorama da cadeia produtiva do leite no Brasil. In: Santos GT, Massuda EM, Kazama DC, Jobim CC, Branco AF Bovinocultura leiteira: bases zootécnicas, fisiológicas e de produção. Maringá: Eduem. pp 9-25 NRC (2001): Nutrient Requirements of Dairy Cattle. 7 ed. Washington, D.C. National Academy Press. 381p NBR ISO 14040 (2009): Avaliação do Ciclo de Vida: Princípios e Estrutura. Associação Brasileira de Normas Técnicas, 21. Rio de Janeiro NBR ISO 14044 (2009): Gestão Ambiental: Avaliação do Ciclo de Vida: Requisitos e Orientações. Associação Brasileira de Normas Técnicas, 46. Rio de Janeiro 458


Sjaunja LO, Baevre L, Junkkarinen L, Pedersen J, Setãlä J (1990): A Nordic proposal for an energy corrected milk (ECM) formula. Proceedings of the 27th Bienal Session of the International Committee for Animal Recording (ICAR) Paris, France: EAAP Publication, pp. 156-157 Valadares Filho SC, Machado PAS, Chizzotti ML (2012): CQBAL 3.0. Tabelas Brasileiras de Composição de Alimentos para Bovinos. Available in: www.ufv.br/cqbal. Accessed in December 2011

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Life-cycle evaluation of the ceramic block with a focus on social interest housing Maria Cecilia Araujo Santos Arnaldo Cardim de Carvalho Filho Maria Cecilia Araujo Santos

MSc. Engenharia Civil – Escola Politécnica de Pernambuco / Universidade de Pernambuco, Rua Benfica, 455, Madalena,Recife – Pernambuco, Brasil.

e-mail: [email protected] Arnaldo Cardim de Carvalho Filho Prof. PhD. Engenharia Civil – Escola Politécnica de Pernambuco / Universidade de Pernambuco, Rua Benfica, 455, Madalena, Recife – Pernambuco, Brasil.

e-mail: [email protected]

Abstract The construction industry is one of the least productive activities, with a high consumption of natural resources and levels of gaseous emissions which contribute to global warming. The exploitation of renewable resources exceeds about 30% of the planet's regenerative capacity, only the ceramics industry estimates a total of 124 million tons of clay per year. Ceramic materials are formed by a high temperature thermal process, typically burnt between 900°C and 1400°C. Within the chain of the ceramic block, the production process is the phase of greater environmental impact due to biomass consumption and gaseous emissions. It is divided into three basic stages: preparation of raw materials (with reduction of the clay particles and damping), material molding (which forms the product) and burning (drying of the material and burning in furnaces for 24 hours). This research creates an inventory of the production process of the ceramic block for sealing in the dimensions 9 x 19 x 19cm, in the state of Pernambuco, Brazil, using the methodology of Life-Cycle Evaluation (LCE) as defined by ISO 14040. It is an experimental research conducted in three industries of the state, where the reference flow used is of 1 ton of clay, to quantify energy consumption (thermal and electrical) and estimate CO2 emissions. The evaluation of inventories shows that during the production process, the preparation of raw material and molding are the steps with greater electricity consumption, and the burning stage responsible for the consumption of biomass for thermal energy generation, which leads to CO2 emissions. The analysis allows to identify that the ceramic block may be a viable alternative for the use in housing of social interest, besides clay being a raw material in abundance in the state, the production process can adopt measures to minimize environmental impact, such as the replacement of native biomass for byproducts and the modernization of the system with the use of low-energy consumption machines. The results when applied to social interest housing, demonstrate the need for the consumption of about 139 kWh of electricity and 272 kg of biomass - resulting in the emission of 0.038 kg/Nm ³ of CO2. The results can be applied to other buildings, and also compared to products with similar function. 460


Keywords: life-cycle evaluation, ceramic block, social interest housing.

1 Introduction Since the Industrial Revolution of the eighteenth century, which began in England – milestone of the economic development of humanity - the demand for the production of consumer goods for the society increased and, consequently, CO2 emissions have become more effective. Cities are responsible for 75% of these emissions and consume about 50% of natural resources, which contribute to the environmental crisis and generate high levels of global warming (Edwards, 2005). Climate change, air and water pollution, destruction of nature, soil erosion, water scarcity and biodiversity loss are the most serious problems of developing countries, aggravated on low-income populations. The researches and applications of principles aimed at sustainability have shown that it is possible to promote a balanced economic growth, reduce poverty and ensure the quality of life of the society (IEG, 2008). This research mainly aims to use the LCE tool to identify energy consumption and CO2 emissions in the production process of the ceramic block, incorporated to the Social Interest Housing in the state of Pernambuco.

2 Inventory of the life-cycle of the ceramic block (ILC) The LCE of the ceramic block was performed from the construction of an inventory of its own production process, with data referring to the consumption of materials and energy, and CO2 emissions. This application is of great value for studying the impacts of the life cycle of the product, since the production of the material is the phase that most degrades the environment. The construction of the ceramic block inventory used to sealing, in the dimensions 9 x 9 x 19cm was carried out through visits to three industries in the state of Pernambuco: one located in Camaragibe, municipality member of the Greater Metropolitan Recife (GMR) and two located in Paudalho, 40 km from the capital. The data regarding the CO2 emissions were collected by a digital meter. Other data were obtained from information supplied by companies or determined by an approximated value. In the region, the municipality of Paudalho is responsible for 70% of the extraction of clay. Consequently, this is a location where numerous industries are located. Among the major suppliers of raw materials, we may also emphasize the municipalities of Vicencia, Passira and Limoeiro. It is important to stand out that this study is limited to the production phase of the ceramic block. For a complete demonstration of the scope of the research, a flowchart of the ceramic block chain was created (Figure 1), based on studies from Soares Pereira and Breitenbach (2002), and on the database created by Kellenberger et al. (2007), who delimits the cutting criteria and defines the inputs and outputs of the life-cycle of the ceramic block.

461


Figure 1 - Flowchart of the life-cycle of the ceramic block. According to the manufacturing system of the ceramic block, the determination of the inputs is the main factor regarding environmental sustainability, thus the choice of the energy matrix defines the profile of the product. The option for the use of fuels with low emissions and materials that are not directly derived from nature establishes a responsibility that involves every sphere of sustainable development: environmental, social and economic. The production process of the ceramic block is divided into three basic stages: preparation of the raw material, molding the material and burning of the product, as shown in Figure 2.

Figure 2 - Flowchart of the ceramic block production process. The preparation of the raw material is accomplished by mixing the clay with a loading shovel, at a ratio of 1:2, being red and black, respectively. After the execution of the trace, the raw material is reduced into smaller particles and moistened. The molding of the material is done by a mill, which compresses the raw material under vacuum and shapes the product. By means of a cutter, the blocks take its dimension for the beginning of the burning process. 462


The burning step is initiated by natural or artificial drying. The first one consists in the storage of the blocks during four days (some industries use greenhouses for the completion of drying) to be sent to the continuous furnace (also known as Hoffman), which conducts the burning within 24 hours. Artificial drying is carried out in 48 hours, in which the blocks are conveyed to a greenhouse and transported into the tunnel furnace. At all stages, there is electric or thermal energy consumption and only at the stage of molding the material there are no CO2 emissions.

2.1 Data collection

Data collection was based on the daily production of the industries visited. To survey CO2 emissions, a digital Instrutemp meter was used, which measures the CO2 concentration in 30 seconds, with the reading of the values in particles per million (PPM). Data were collected at a one-hour period and recorded every twenty minutes. In Brazil, studies of CO2 use milligrams per normal cubic meter (mg/Nm³) as a unit reference. It is a more common unit of volume, used as the basis for measuring exhaust emissions. This conversion is performed by the following formula (CATERPILLAR, 2007): mg/Nm³ = PPM x P x MW RxT In which: P = pressure in kPa for normal conditions, 101,3 kPa MW = molecular weight of the exhaust component R = universal constant of the gas, 8,3144 kN m / kmole K T = temperature in Kelvin degrees, i.e., 273,15 ° K (0 ° C) for normal conditions Substituting these constants and the molecular weight of the component to the equation, the formula can be defined as: mg/Nm3 = PPM x mg/Nm3 Inwhich the conversion factor is of 1 PPM of CO 2 = 1,963 mg/Nm³ For the data collection from electric energy consumption, the values were collected from the power of the engines of the machines used in relation to hours worked daily. The power unit is presented by HP (horsepower) and energy consumption in kWh (kilowatt-hour). Considering HP = 1.36 1 kw, we have: T = P x t Where: T = electric work in kwh P = power in kw t = hours worked per day For the collection of data of the consumption of natural resources, a clay (kg) survey was made and the type of materials used in the drying and burning of the blocks. These were: wood (m³), cane briquette (kg), vegetable oil (kg) and sawdust (kg). It is important to emphasize that, for the values of clay, the information is provided by industries and for the values of other resources, information was sometimes provided, or sometimes measured onsite. 2.2 Industry A

Industry A is located in Camaragibe and its daily production of ceramic blocks is of 30.600 units. Daily, 92 tons of clay are used. From this amount, 30% correspond to red, 50% to black and 20% for white. In order to elaborate the reference flowchart (Figure 3), the following aspects were considered:  Measures for 1.000 kg of clay.  Consumption values of diesel from loading shovel  Emission of CO2 from Hoffman furnace and from stackers  Lack of information about the power of the chimney exhausts

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Figure 3 - Flowchart of inputs and outputs of the production process of industry A. 2.3 Industry B

Industry B is located in Paudalho and its daily production is of 45.000 blocks. Its energy matrix consists of electricity - from a thermoelectric power plant – and thermal, resulting from combustion of wood, sawdust and furniture residue. It is important to emphasize that there was difficulty in collecting the CO2 emission values in this industry due to the chimney height and the lack of maintenance points (as in other industries). Therefore, the exhaust was shut down so the gaseous emissions could exit through feeding openings of the lines of the furnace and the equipment positioned 1 m high in order to obtain the desired results. This process was repeated at 20 minute intervals for 1 hour. To elaborate the reference flowchart (Figure 4), the following aspects were considered:  Measures for 1.000 kg of clay.  Consumption values of diesel derived from the loading shovel  Emission of CO2 from the Hoffman furnace  Lack of information about the power of the greenhouse exhausts and chimneys  Same power as the engine from industry A for the value regarding the energy consumption of the pneumatic cutter.

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Figure 4 – Flowchart of inputs and outputs of the production process of industry B. 2.3 Industry C

The third industry visited also located in Paudalho manufactures daily 133.000 ceramic blocks. In 2009, the company acquired a certificate of reduction of CO2 emissions through fuel switching from non-renewable biomass by renewable biomass. However, this certificate has not been updated. The industry works with continuous and tunnel furnaces and its energy matrix is constituted of electric energy, from hydroelectric and thermal plants, resulting from the combustion of biomass (sugar cane briquette, bamboo powder, sawdust, firewood, babassu nut and vegetable oil). It is important to emphasize that daily, the company replaces electricity for four hours run by a diesel generator. For this reason, the amount of CO2 emission that this industry produces was divided, in the reference flowchart between all devices that function through electrical power in order to show that devices do not generate emissions, for being electric, begin to discharge when using the generator. Daily, 376 tons of clay are used in the production of ceramic blocks. To elaborate the reference flowchart (Figure 5 on next page), the following aspects were considered:  Measures for 1.000 kg of clay.  Consumption values of diesel and emission of CO2 derived from the generator divided between equipments depending in its functionality.  Lack of information about the power of the greenhouse exhausts, chimneys and wood cutter.  Same power as the engine from industry A for the value regarding the energy consumption of the pneumatic cutter.

465


The choice of the three industries was due to the access granted for the collection of data and information by the owners. A total of 18 industries were contacted among the registered in the Anicer´s institutional site, informed by Sindicer and the ones available in the phone book. However, only 3 facilitated the access and data collection, whereas two are located in the Zona da Mata mesoregion (Paudalho) and one in the Metropolitan Region (Camaragibe). The results found can be used in other regions, since the technology adopted does not change for other locations (information collected at the time of telephone contact).

Figure 5 – Flowchart of inputs and outputs of the production process of industry C.

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3 Inventory evaluation of the life cycle of the ceramic block For presentation of the data defined, a conversion of units in the parameters of universal measures was performed. Thus, the values corresponding to the electrical and thermal energies are presented in megajoule (MJ), a measure of heat energy and CO2 emissions in kg/Nm³. For this, the following conversion factors were considered: Table 1 – Conversion Factors of measures. 1 kWh

3,6 MJ

1 m³ of firewood

340 kg de firewood

1 kg of firewood

11,59 MJ

1 kg of sawdust

10,50 MJ

1 kg of cane briquette

9,62 MJ

37

36,43 MJ *

1 mg/Nm³

0,000001 kg/Nm³

1 kg of vegetable oil

Table 2 presents a summary of the data obtained, corresponding to a ton of clay. Table 2 - Data obtained referring to a ton of clay. Ind. A

INPUTS

OUTPUTS

Electric power consumption 23 (kWh/t) Thermal power 356 consumption (MJ/t)

Ind. B Ind. C 11

12

465

77.000

CO2 Emission (kg/t)

0,0053

0,0032

0,0042

Blocks (unit/t)

333

333

354

During the production process, the preparation of the raw material and the molding are the steps of greater electricity consumption due to the use of high power equipment, such as the laminator and the mill. Moreover, the working hours of the industries are the determining factor for this use, since the greater the working period, greater is the consumption. The step of burning, is characterized by being the phase of greater environmental impact due to the combustion of biomass. It is noteworthy to say that industries B and C use mesquite wood as a component for combustion, material derived directly from nature. Industry A presents the highest value in relation to energy consumption and CO2 emissions, which indicates the use of equipment with high power engines and use of more polluting biomass than other industries. Machines run daily for nine hours and the furnace for 24 hours in the production of ceramic blocks. Although it is presented as the most polluting material, the cane briquette is a byproduct, a feature that minimizes the environmental burden generated by emissions. Industry B showed lower results concerning energy consumption - due to the use of equipment with low power engines, even with hours of operation equal to industry A - and CO2 emissions. Industry C, on the other hand, in order to reduce the consumption of electricity, replaces the matrix by a generator that works on burning diesel for four hours, contributing to gaseous emissions. As to the consumption of thermal energy, industry C had a much higher value than industries A and B due to the use of two furnaces: the continuous and the tunnel. For the continuous furnace firewood and vegetable oil are used the latter being characterized by high calorific and energy potential, three times superior than firewood. As for the tunnel furnace, a mixture of cane briquette, sawdust and firewood is used and its daily production is

* Value regarding weighed average of vegetable oils from dendê (38,09 MJ/kg), peanut (37 MJ/kg), soy bean (36,87 MJ/kg), babaçu (35,29 MJ/kg) and castor (34,90 MJ/kg), (NERI, 2000). 467


superior to the continuous furnace, for two days are enough so that the process is completed, while the continuous furnace requires four days. Among the industries studied, it can be considered that industry C has lower values for emission due to the quantity of blocks burnt for each ton of clay, adding the utilization of two furnaces in the burning process. 3.1 Interpretation of the results

The data regarding the biomass show that the cane briquette (industry A) has lower calorific value and energy than firewood and sawdust (industry B) - however, as a byproduct, it can achieve better results and be used along with products of high calorific value, such as vegetable oil, used in industry C. The consumption of biomass in industry C is superior to other industries because of the use of the two methods of burning. Despite not showing lower results, it is possible to consider that industry C consumes less energy and has a lower amount of emissions by making more products with a ton of clay. Table 3 - Analysis of the contribution by stage of the life-cycle of production. Preparati on of raw material

Molding of material

Burning

TOTAL

Consump tion of electric energy (MJ/t)

50%

50%

0%

100%

Consump tion of thermal energia (MJ/t)

0%

0%

100%

100%

Emission of CO2 (kg/t)

5%

0%

95%

100%

In the phase of preparation of the raw material, the power consumption is very important and this can lead to the study of alternatives with positive contribution to the environment. Although it avoids power consumption for four hours, the use of generator by industry C is a polluting source, since it uses the combustion of diesel for its operation. As the industries are located in full sunny and perennial environments, they could use photovoltaic panels for its energy matrix and take advantage of the weather for power generation. The burning phase is relevant for the study of consumption of thermal energy for being the only step that uses biomass combustion. Performed by all industries analyzed, the use of firewood to start the fire in the furnace can be replaced by continuous briquette cane and fueled with vegetable oil, as both showed low CO2 emissions throughout the study. The preparation phase of the raw material had negligible influence on the emissions of CO2 in the lifecycle of production, because the only source of this gas is loading shovel - a machine that uses combustion of diesel for its operation. This measure can be reversed by the use of cleaner fuels.

3.2 Case study

The case study was conducted in a social interest housing which integrates a housing project located in the city of Paulista (Metropolitan Region of Recife), 18 km from Recife, destined for the low income population occupying irregular, environmental protection or risky areas. The typologies most commonly found in the state of Pernambuco are performed in ceramic block masonry for sealing - often used with structural function in the dimensions 9 x 19 x 19 cm, with eight holes horizontally, Figure 6 - and concrete blocks dimensions 9 x 19 x 39 cm, Figure 7. 468


Figure 6 – Ceramic block 9 x 19 x 19 cm.

Figure 7 – Concrete block 9 x 19 x 39 cm.

The tradition of use of ceramic blocks in state is due to the abundance of the raw material in the region. Some towns like Limeiro, Passira, Paudalho and Vicencia are large suppliers of this resource. Most industries that manufacture the product are also found in these locations. The housing complex studied as reference in this dissertation is part of the My Home program and its typology is marked by the use of ceramic blocks in the dimensions 9 x 19 x 19 cm, as uncoated masonry sealing, covered with a wood frame and ceramic tiles, with dry painted wooden framing with oil paint. Each unit has approximately 40 m² of built area (Figure 8).

Figure 8 – Pattern of housing in ceramic blocks.

Characterization of housing:  Built area: 40 m².  Necessity program: living room, kitchen, bathroom and two bedrooms.  Foundation: non-structural concrete (1:4:8) and structural concrete with FCK=30MPA, both thrown and plotted.  Masonry: ceramic blocks with eight holes horizontally (9 x 19 x 19 cm), settled and grouted with cement mortar and sand in 1:3 ratio, with a thickness of 1.50 cm and textile blocks of pressed cement, coated in roughcast with mortar cement and sand in 1:3 ratio and latex painting with no spackle.  Cover: wood structures with spacing of up to 4 m and colonial-type ceramic tile.  Framing: dry wood painted with oil paint.  Wet areas: ceramic 30 x 30 cm applied on the walls of up to 1,50 m and on the bathroom floor. Given the values found in Chapter 3, it is possible to generate an average of data collected in the three industries surveyed. Considering 1 m² of masonry as a functional unit, it is possible to identify CO2 emissions and energy consumption for any building that uses the ceramic block as sealing material. Table 4 - Results for 1 m² of masonry. VALUE Biomass (kg/m²)

consumption

2,43

INPUTS Electric energy consumption (kWh/m²)

1,25 469


OUTPUTS

Emission (kg/m²)

of

CO2

Blocks (unit/m²)

0,0003 28

For the construction of a social interest housing with 40 m², a total of 3.125 units of ceramic blocks were necessary. According to the data in Table 4, it is possible to establish the values shown in Table 5. Table 5 - Results for housing with 40 m². VALUE

INPUTS

OUTPUTS

Biomass consumption (kg/40m²)

271,50

Electric energy consumption (kWh/40m²)

139,15

Emission of (kg/40m²)

0,038

CO2

Blocks (unit/40m²)

3.125,00

Therefore, to construct a 40 m² house, it is necessary to consume approximately 139.15 kWh of electricity and 271.50 kg of biomass - which results in the emission of 0.038 kg / Nm ³ of CO2.

4 Final considerations The consumption of natural resources for the production of construction materials intensifies the effects of environmental impacts. So far, only nature proved fully effective in improving air quality, for only plants are capable of photosynthesis (natural process that turns carbon dioxide into oxygen). Even if society changes its daily habits and customs, it will continue to contribute to the negative impacts to the environment. The preparation of the inventory from the LCE methodology allowed us to identify the inputs and outputs of the production system to qualify and quantify consumption and CO2 emissions. It is an important tool for the study of environmental impacts for they may enable the realization of a diagnosis to make decisions that can define environmental quality and therefore, the quality of life of the society. The ceramic block is the most used product in civil construction in Pernambuco characterized by low cost, easy access and use of unskilled labor. However, the intense use of this material affects the environment, either solid or gaseous. Its production has a high consumption of electrical and thermal energy and demonstrates the potential contribution to global warming with CO2 emissions and consumption of non-renewable resources. The value of CO2 emission may seem meaningless if used for manufacturing 340 ceramic blocks, however, when adapted to every house in housing complex, it is possible to scale its influence on global warming. Experimental research has allowed to identify that the utilization of biomass in the burning of the product may be a feasible alternative if used as a byproduct, such as the cane briquette. Firewood, although appears effective with high calorific value, may be replaced by cane briquette and also by vegetable oil. The use of furniture and vegetation residues may also be a viable alternative to the process of burning, in addition to contributing for the elimination of residues.

References ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS. NBR 14040: Gestão Ambiental – Avaliação do ciclo de vida – Princípios e Estrutura. Rio de Janeiro, 2009. NBR 14044: Gestão Ambiental – Avaliação do ciclo de vida – Requisitos e orientações. Rio de Janeiro, 2009. BP, Statistical Review of World Energy, 2011. http://www.bp.com CALLISTER JR, W. D. Fundamentos da ciência e engenharia dos materiais: uma abordagem integrada. Rio de Janeiro – RJ, 2 ed., LTC, 2006. CATERPILLAR. Gas Engine Emissions – Application and Installation Guide. Estados Unidos, 2007. 470


http://www.scribd.com CARVALHO FILHO, A. C. Análisis del ciclo de vida de productos derivados del cemento – Aportaciones al análisis de los inventários del ciclo de vida del cemento. 2001. Tese, 297p. Barcelona, jul.2001. CONFEDERAÇÃO NACIONAL DA INDÚSTRIA – CNI. Matriz energética: cenários, oportunidades e desafios. Brasília, 2007. http://www.cni.org.br. EDWARDS, B.; G uia básico para a sustentabilidade. 2.ed. 226p., Barcelona, RIBA Enterprises, 2005. INDEPENDENT EVALUATION GROUP – IEG. Sustentabilidade Ambiental: uma avaliação do Grupo Banco Mundial (Resumo de Avaliação), 28p., Washington D.C. – EUA, Copyright, 2008. http://worldbank.org/. INTERGOVERNMENTAL PANEL ON CLIMATE CHANGE – IPCC. Cambio climático 2007: Informe de síntesis, Ginebra, Suiza, 104 págs. http://www.ipcc.ch. KELLENBERGER, D.; ALTHAUS, H. J.; JUNGBLUTH, N.; KÜNNIGER, T.; LEHMANN, M.; THALMANN, P. Life Cycle Inventories of Building Products. Final report ecoinvent data, v.2, n.7. EMPA Dübendorf, Swiss Centre for Life Cycle Inventories, CH: 2007. http://www.ecoinvent.org. LOVELOCK, J. Gaia: cura para um planeta doente. 192p. São Paulo: Editora Cultrix, 2007. NERI, J. T. Dados de Unidades de Conversão. Natal – RN, Centro de Tecnologia do gás, 2000. http://lspsteam.dominiotemporario.com SOARES, S. R., PEREIRA, S. W., BREITENBACH, F. E..Análise do Ciclo de Vida de Produtos Cerâmicos da Indústria da Construção Civil. In: CONGRESSO INTERAMERICANO DE INGENIERÍA SANITARIA Y AMBIENTAL, 28., 2002, México. Anais... Santa Catarina: Departamento de Engenharia Sanitária e Ambiental (UFSC), 2002, 8p. http://www.bvsde.paho.org WORLD WILDLIFE FUND – WWF. Relatório Planeta Vivo 2008, 48p., versão portuguesa coordenada por: CESTRAS, 2008. http://www.cestras.org/planetavivo2008.pdf

471


LCA of lighting products: looking for methodological consistency Oswaldo Sanchez Júnior* * Researcher at the Institute of Technological Research of the State of São Paulo - IPT and Student of Postgraduate Program in Energy, University of São Paulo - PPGE Prof. Almeida Prado Avenue, 532, Cidade Universitária, Butantã, São Paulo, CEP 05508-901, São Paulo, Brazil.

++55 011 37674588 [email protected] or [email protected] http://www.ipt.br or http://www.energia.usp.br/energia/

Abstract Introduction The technique of Life Cycle Assessment - LCA has been increasingly used for resource management and development of products and services in the lighting segment. However, there are inconsistencies in particular regarding the definition and use of the functional unit designed more to products than to users, which limits the validation and comparison of these studies. Objective This study aims to establish a minimum protocol for the application of the technique for this segment incorporating the importance of services to the final user. Method This study was a compilation of comparative LCA studies of lighting products published. The elements of economic, social and environmental dimension were mapped and studied even considering its applicability to the inventory step of LCA and a roadmap for defining the Functional Unit was proposed. Results It was observed that the interest in LCA studies is more focused on general lighting, focusing on the products and materials used in services. Therefore, it is possible to incorporate other variables affecting results for the user, which would make the studies more effective and comparable. Conclusions The definition of a protocol leads to gains for everyone (producers and users of LCA studies), it allows greater transparency and uniformity in the analysis, adding value to the work and broadening the spectrum of its use, according to the approach described in the objective. Keywords: LCA of lighting products, comparative LCA.

Introduction Innovations in products and installation projects for lighting fell on the searchfor energy efficiency, 472


increasingly demanding the use of analytical tools for decision support. Moreover, with the expansion of concerns about the environment since the late 1980s, the production and consumption of energy began to be considered under the aspect of environmental impacts associated with these activities. In this context, tools such as Design for the Environment (Design for Environment - DfE) and Life Cycle Assessment - LCA began to be used for resource management and development of products and services. With this emphasis, there were many ACV studies for lighting products since the early 2000's, however, there are inconsistencies in the application of this technique, particularly regarding the definition and use of the functional unit, which limits comparison and validation of these studies. Moreover, the absence of parameters associated with the quality of the illumination service focused on the final user (rationale of lighting installations) restricts further qualified analysis and comparison of studies of ACV.

Objective With the motivation to overcome this inconsistency, this study sought to identify the main figures of merit present in the stage of defining the purpose and scope of the LCA to establish a minimum protocol for the application of the technique for this segment.

Method The implementation of an LCA study, as Brazilian and international standards for environmental management, should follow a sequence of activities. This paper will focus on research, analysis and discussion of the first phase of the application of the technique of ACV, which comes to the Purpose and Scope Definition stage. For cases of LCA performed for environmental assessment of lighting products, there is

a number of

preventions required specifically for this stage that can organize and facilitate the work from the beginning, but, on the other hand, may lead to misunderstanding and to surface evaluations and biased. The working hypothesis adopted for this research is that the initial definition of the proper and judicious Functional Unit in cases of LCA of lighting products can offer the "ball of yarn" to organize the process of getting the other necessary elements. According to ABNT NBR ISO 14040, Functional Unit is: ―...the quantified performance of a product system for use as a reference unit in a study to assess the life cycle‖.

However, in cases of LCA of products for lighting, setting the Functional Unit must necessarily take into account which of the various niches and subniches applications (street lighting, commercial, industrial or residential) the study is inserted, due to the fact that lighting services cater to different requirements of its users and demand the use of products with different characteristics. Considering that each niche has its metrics and demands and it is inserted in a particular way in the supply chain, it is expected that each one has its own reality in terms of functions to which the products and facilities must attend To identify the key figures of merit associated with niche applications for lighting and arrange them in an 473


objective manner to facilitate the early LCA studies, it was done a survey and an analysis of the major papers describing LCA of products and services for illumination published in academic databases, identifying and comparing their elements from the design of ACV heralded by ABNT NBR ISO 14040. We also carried out a survey and an analysis of major works that address the quality of lighting and its influence on productivity and human behavior. Thus, were established the main parameters that allow the definition of functional units appropriate for each application of lighting services and, therefore, the identification of gaps that could be overcome by applying a sequence of simple steps in order to make more practical the phase of the LCA called Defining the Purpose and Scope.

Data Survey In the interest shown above, there was a non-exhaustive search of scientific articles to evaluate the scope and approach typically performed in implementing LCA studies, particularly in the illumination area. The used databasewas composed of collections accessible through the portal serial Capes. We also carried out a nonexhaustive search of scientific articles that deal and qualify the quality of lighting services, in particular its influence to human productivity. The used database was composed of collections accessible through the portal serial ―Capes‖. Among other relevant issues, we must remember that the definition of service quality lighting changes a lot depending on culture and geography. This is partly due to differences in habits when it comes to urban and rural life, of the circadian cycle of the majority population, the level of education and purchasing power of the population, the urban reality in cities with large human concentrations, insolation in the geographic region and its annual seasonality, supply and availability of lighting technologies, besides, of course, the type of activity for which the service lighting plays an aggregation of comfort, safety and productivity or visual performance.

Analysis The published works of ACV lighting products (total of 10) can be analyzed as follows. Concerning the objectives, there is not much novelty, all of them are provided and cited by the ABNT NBR ISO 14040. The main objectives are technical support to public policies,use as element of analysis in the design phase of the product (ecodesign) and also as a strictly academic subject to study environmental impacts associated with the final use of electricity. The use of the technique of LCA as an element of technical support for the commercial sector of firms that sells new technologies also seamed promising. The scope of published works is mostly comparative studies, which seek to present results from the comparison of a product of interest with his conventional counterpart or more popular. While there is greater interest in one or another stage of the life cycle of lighting products (notably the use or operation phase where the bulk of energy consumption occurs), most studies sought to give a sympathetic character (complete) to the product system considered. The Functional Unit defined in the work is heterogeneous, with no similarities in the extent or the depth of scope. 474


It is observed that the emphasis given to studies is almost always in harmony with the objectives but tied to the interests of who performs the work or sponsors. This becomes clear when one observes almost always the findings reported. It is observed that application in LCA studies are more focused on residential lighting, commercial technologies and "generic" (products that were not designed for a specific environment) but able to be attached to lamps for applications in specialized functions. Therefore, various segments, such as public lighting, deserve further attention. As for the geographical region considered in the works, it is observed that Europe is the object of interest of most of them and, in smaller numbers, the U.S.. Considering that the phase of analysis of the environmental impacts should take into account local and global impacts, but uses data from databases generated for specific places (most of them made by European companies and institutions), the lack of jobs is evident, considering the reality of the southern hemisphere and mostly Latin America and Africa reality. For example, Brazilian energy matrix is presented with a very different profile compared to the one of the matrices used in analyzes. No work has addressed the social dimension of the life cycle, although there are tools already proposed for this approach (inventory software allow various categories of impacts for this review), considering the tripod economy, society and environment, a sustainable development model proposed by Elkington (1998), known as TBL. Finally, it is clear that the analysis of costs associated with LCA studies are not unanimity. Despite of recurrent motivation to guide decisions by economic parameters, this issue is not even contemplated in many of the studies. Work on power quality (total of 12) can be analyzed as follows. As to the objectives of the work, the intention is mainly to identify rules in relations between ambient light and its effect on work performance and well-being to support designers and specifiers. It almost always seeks to be a standardization of recurring situations. Concerning the methods,

two basic types are used: literature review and discussions with experts or

experiments that simulate those situations that supposedly represent interests. Regarding the application area of lighting services under review, there are studies that cover most lighting applications, approaching from internal and external environments, but most of them are concerned about the visual aiming productivity (great interest in the productive sectors and trade). As for the quality parameters monitored, there is much heterogeneity, depending on interest and availability of resources. The objective parameters most cited are: level of illuminance, luminance, luminous spectrum, contrast and light distribution. Regarding the areas where the works were done, there was a predominance of interest in Europe and USA.

Discussion and Conclusions Because of these technological and behavioral changes, it is understandable that the exercise of practices focused on environmental sustainability, such as the use of LCA for environmental management of facilities and services, lies on the problem of the use of energy and energy efficiency in services lighting, among others. The generation, transmission and distribution of electricity are major villains in the balance of environmental impacts in any modern society. However, the strict focus on technologies or products of lighting, mainly aiming

the evaluation of unquestionable environmental impacts in the use phase (due to

electricity 475


consumption for conversion of light over useful life), brings a mistake that is not to consider the effect of the operation of installations for the final user. For example, efficient products can constitute inefficient instalations from the point of view of the final user. On the other hand,, products considered ineffective, if well placed and routed, can offer quality lighting for both productive activity and comfortable living. The survey and its analysis allow the identification of methodological gaps in the use of LCA for lighting products and services. Clearly the lack of a standard approach makes the LCA technique relatively arbitrary, and in this sense, devalues its potential as an analytical tool. Moreover, it ends up functioning more as a marketing tool than as an element of transformation of consumption-production ratio. As big fans of the LCA art, we have developed a roadmap that proposes the organization and the insurance of a minimum of consistency for those interested in environmental management of lighting services. Imagined from the analysis of the references mentioned earlier, two complementary axes are proposed to the use of ACV in these cases, see Figure 1. There are specific requirements and technical standards that must be met so that the choices reflect products with safety, durability, reliability and other qualities that are not directly linked to the service enjoyed by the user, but the financial impact and return on investment, for example, and should be considered in defining the functional unit. Despite of being very common the development focused on technology or product lighting, this approach alone is insufficient for conducting a LCA qualified and comprehensive. With only this approach, some dimensions are excluded, such as the aesthetics and the exercise of a series of visual capabilities, which powerfully influences the desired result with the lighting services.

476


Figure 1 - Proposed Roadmap for Phase 1 of the LCA area lighting. By focusing on service or user, the goal is to capture and translate in all aspects of LCA (or at least the main ones) the influence of the actual outcome of lighting services to the final user that, in the end, is the main interested in an environmentally responsible management of the service. The script offers step-by-step the construction of specifications, that complete, compose the definition of 477


appropriate Functional Unit. In the common aspects of the two focuses, such as the definition of the geographic region and time period considered, configuration technology and facilities considered, the level of detail of the processes to be mapped (depth LCA) and the life cycle stages that compose the product system (extension of LCA), the script would help in the settings due to the fact that the two outbreaks have already defined the main dependencies. Finally, a contraposition of the settings with the initial goals would be conducted in order to ascertain their satisfaction. If not, another round would be held to achieve consistency and harmony. Eventually the same path could be followed by another study, realized by another team, that if compared, could lead to figures of merit equivalent or even similar. This would greatly facilitate the exchange of such knowledge.

References Abdou, O.A. (1997) Effects of Luminous Environment on Worker Productivity in Building Spaces, Journal of Architectural Engineering, setember ASSOCIAÇÃO BRASILEIRA DA INDÚSTRIA DA ILUMINAÇÃO (2005) Levantamento do Estágio Tecnológico

do

Setor

de

Iluminação.

São

Paulo:

Abilux,

Available:

http://www.abilux.com.br/pdf/diagnostico.pdf>. Accessed: 04 set. 2009. ASSOCIAÇÃO BRASILEIRA DE NORMAS TÉCNICAS – ABNT (2009) Gestão ambiental - Avaliação do ciclo de vida - Princípios e estrutura, ABNT NBR ISO 14040. Rio de Janeiro: ABNT Blengini, G. A.; Di Carlo, T. (2010) Energy-saving policies and low-energy residential buildings: an LCA case study to support decision makers in Piedmont (Italy), Int J Life Cycle Assess 15:652–665 Dubberley, M.; Agogino, A.M.; Horvath, A. (2004) Life-cycle Assessment of an Intelligent Lighting System Using a Distributed Wireless Mote Network; ISEE '04 Proceedings of the International Symposium on Electronics and the Environment; Pages 122-127; IEEE Computer Society Washington, DC, USA; ISBN:07803-8250-1 Elkington, J. (1998) Cannibals with forks: the triple bottom line of the 21st century business. Gabriola Island, CA: New Society Publishers, The Conscientious Commerce Series Eloholma, M. et al. (2005) Mesopic models*/from brightness matching to visual performance in night-time driving: a review; Lighting Res. Technol. 37,2 pp. 155_/175 EMPRESA DE PESQUISA ENERGÉTICA – EPE (2008) Balanço Energético Nacional 2008: Ano base 2007. Rio

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. Accessed: 04 set. 2009 Fostervold, KI, Nersveen, J. (2008) Proportions of direct and indirect indoor lighting – The effect on health, well-being and cognitive performance of office workers; Lighting Res. Technol. 40: 175–200 Fotios, S., Cheal, C. (2007) Lighting for subsidiary streets: investigation of lamps of different SPD. Part 1— Visual Performance, Lighting Res. Technol. 39,3 pp. 215–232 Garrett, P.; Collins, M. (2009) Life Cycle Assessment of Product Stewardship Options for Mercury-Containing Lamps in New Zealand: Final Report , Environmental Resources Management (ERM), for the Ministry for the Environment, New Zealand Goodman T, Gibbs D and Cook G. Better (2006) Lighting for Improved Human Performance, Health and Well-Being, and Increased Energy Efficiency – A Scoping Study for CIE-UK, NPL Report DQL-OR019, National Physical Labouratory, Teddington 84 pp 478


Hansen, M. (2009) Energy-Efficient Lighting Lifecycle – White Paper, Cree, Inc. Hartley D.; Jurgens, C.; Zatcoff, E. (2009) Life Cycle Assessment of Streetlight Technologies, University of Pittsburgh, Pittsburgh, PA Izsó, L. et all (2009) Psychophysiological, performance and subjective correlates of different lighting conditions; Lighting Res. Technol. 41: 349–360 Loe, DL. (2009) Energy efficiency in lighting – considerations and possibilities; Lighting Res. Technol. 41: 209–218 Mayhoub, MS; Carter, DJ. (2012) Hybrid lighting systems: Performance and design; Lighting Res. Technol. 44: 261–276 Navigant Consulting Europe (2009) Life Cycle Assessment of Ultra-Efficient Lamps, London Osram (2009) Life Cycle Assessment of Illuminants A Comparison of Light Bulbs, Compact Fluorescent Lamps and LED Lamps, Osram, Alemanha Ramroth, L. (2008) Comparison of Life-Cycle Analyses of Compact Fluorescent and Incandescent Lamps Based on Rated Life of Compact Fluorescent Lamp, Rocky Mountain Institute, February Rutter, P.; Keirstead J. (2012) A brief history and the possible future of urban energy systems; Energy Policy 50 72–80 Techato, K.; Watts, D.J. ; Chaiprapat, S. (2009) Life cycle analysis of retrofitting with high energy efficiency air-conditioner and fluorescent lamp in existing buildings, Energy Policy 37, 318–325 Veitch et all (2008) Lighting appraisal, well-being and performance in open-plan offices: A linked mechanisms approach; Lighting Res. Technol. 40: 133–151 Wang, N.; Boubekri, M. (2011) Design recommendations based on cognitive, mood and preference assessments in a sunlit workspace; Lighting Res. Technol. 43: 55–72 Welz, T.; Hischier, R.; Hilty, L. M. (2011) Environmental impacts of lighting technologies — Life cycle assessment and sensitivity analysis, Elsevier, Environmental Impact Assessment Review 31, 334–343 Wilhelm, B. et all (2011) Increased illuminance at the workplace: Does it have advantages for daytime shifts?; Lighting Res. Technol. 43: 185–199

479


Comparison of different methods for vinasses treatment from the bioethanol industry based on LCA Nishihara Hun, Andrea L.*– Mele, Fernando D. – Hernández, María Rosa Dep. Ing. de Procesos y Gestión Industrial – FACET –Universidad Nacional de Tucumán, Av. Independencia 1800, San Miguel de Tucumán, Argentina

* +54 381 410 7573, [email protected]

Abstract This paper presents a comparative study of the environmental impact of the main waste of the sugar-alcohol industry, vinasses, considering three options for treatment: field fertigation, anaerobic digestion in UASB reactors and concentration (60%) for combustion in natural gas boilers, using in each case the technique of Life-Cycle Analysis (LCA). Keywords Sugar-alcohol industry, Sugarcane, UASB reactors, Fertigation, Evaporation

1 Introduction With the approval of National Law 26093 on biofuels, sugar and ethanol activities has had a major boost in northwestern Argentina (NOA), the main drawback being the generation of large volumes of vinasses, a highly polluting liquid effluent. It is necessary to propose alternative ways to reduce and treat the vinasses generated by evaluating each of these pathways not only on their technical and economic viability, but also on their environmental impact. Thus the aim of this work is to apply the methodology of Life-Cycle Analysis (LCA) for the study and comparison of different options of treatment for vinasses. This work was performed as part of a Federal Production Innovation Project (PFIP) funded by the Ministry of Science, Technology and Productive Innovation of Argentina.

2 Background While bioethanol derived from sugarcane is considered as an environmentally beneficial option, there are some drawbacks associated with this biofuel to be analyzed all together such as competition with food for land, the impact associated with the transportation sector during the agricultural and logistics tasks, and the generation of large amounts of stillage during the process. Particularly, one of the aspects not taken into account so far is how the treatment of vinasses affects the environmental impact of the ethanol production in Argentina, from a LCA perspective. Regarding the LCA applied to the sugarcane-based ethanol, most of the contributions in the literature are related to production in other countries. It is worth noting that all these works are recent, tackling the bioethanol production mainly in Brazil (Cavalett et al. 2011a,b; Luo et al., 2009; Ometto et al. 2009, 480


Roberto et al. 2009; Seabra et al., 2011), but also in other countries such as Australia (Renouf et al. 2011), Colombia (Sánchez et al., 2007), Cuba (Contreras et al., 2009), Mexico (García et al., 2011) and Thailand (Nguyen and Gheewala, 2008). The LCA studies on the sugar/bioethanol industry in Argentina are incipient. An application that can be mentioned is the work by Mele et al. (2011). The importance of evaluating the sugarcane ethanol in Argentina from the LCA point of view is based on: (i) this fuel is based on renewable resources, in contrast to other types of fuels; (ii) sugarcane originates one of the main economic activities in rural areas of NOA, with many environmental and social implications; (iii) a specific local approach is crucial in the LCA-based evaluation of bioenergy systems; (iv) being vinasses generation the main constraint against the feasibility of the bioethanol projects, it is important to include in the studies how the final disposal of the stillage affects the environmental performance of the whole system.

3 Methodology Data utilized in this paper come from an industrial complex of NW Argentina (NOA). It comprises a plant that manufactures sugar (mill) coupled to a plant that produces ethanol (distillery). As time boundaries, a harvest year was considered (zafra), from May to November 2010. To define the spatial boundaries of the system, the approach "form cradle to gate" has been used, that is from raw material –sugarcane– cultivation until the production of sugar and bioethanol as finished products. The whole system has been divided into three subsystems: Agriculture, Mill and Distillery. In the subsystem Agriculture, sugarcane is planted, treated with agrochemicals, harvested and transported to the sugar mill. In the subsystem Mill, sugar is obtained as a product whereas bagasse, filter muds and molasses are generated as by-products. Bagasse is the lignocellulosic residue of the sugarcane after milling, which is burned in boilers to generate power in the plant itself, and it is not a net outflow. The filter muds are sludges resulting from the purification step of the juice, which are recycled to the subsystem Agriculture. Molasses are the final honeys with high content of non-crystallizable sugars, which are sent to the distillery. In the subsystem Distillery, the molasses, through fermentation, distillation, and other processes, becomes alcohol 96 % vol. firstly, and then, absolute (anhydrous) alcohol with a purity higher than 98 % vol. Moreover, with regard to vinasses, the main liquid effluent from the distillery, three alternatives treatment methods has been considered, which will be described in section 4. As a functional unit a mass flow has been taken: 100 t of harvested sugarcane, ready to enter the mill. Inputs and outputs of each subsystem have been identified and quantified (LCA inventory phase). 90 % of the data has been provided by the company. The remaining 10 %, such as some emissions to air, water and soil whose information was not available, has been obtained from literature. In all the cases, mass allocation has been used as allocation method. The LCA study has been done with the aid of the program SimaPro ® using as an impact assessment (impact assessment phase of LCA) the Eco-Indicator 99.

4. Case Studies Three options of vinasses treatment have been taken into consideration: fertigation of the crop field, anaerobic 481


digestion in reactors UASB and concentration (until 60 %) to burn the concentrated vinasses in natural gas boilers. Case I: Fertigation of the fields

This alternative considers that vinasses are sent to the sugarcane fields for irrrigation. Tables 1, 2 and 3 show the main input-output data considered in this cases study for the subsystems: Agriculture, Mill and Distillery.

Table 8. Subsystem Agriculture. Amounts referred to 100 t of sugarcane. Inputs

Amount

Outputs

Amount

Outputs

land use

0.856 ha

harvested sugarcane

100 t

Emissions

Amount from

harvest

burning Solmix

281 L

O2

26.72 t

CH4

2.482 kg

diammonium

321 L

Emissions to the air

N2O

0.171 kg

TCA

3.25 kg

N2O nitrification

14.55 kg

NOx

9.074 kg

Dalapon

2,44 g

NOx

24.31 kg

SOx

1.113 kg

Ametrina

1.71 L

NH3volatilization

3.852 kg

NMVOC

5.564 kg

Atrazina

1.71 L

Emissions

phosphate

to

the

Emissions

water Decis

0.073 L

from

diesel

combustion

NO3lixiviación

40.061

CO

2.754 kg

kg Diesel

16.2 L

phosphate

2.054 kg

NOx

4.82 kg

filter muds

6.31 t

pesticides

32.357 g

SO2

0.551 kg

CO2

36.13 t

particles

67 mg

Table 9. Subsystem Mill. Amounts referred to 100 t of sugarcane. Inputs

Amount

Outputs

Amount

Sugarcane

100 t

white sugar

9.995 t

natural gas

22.58 m3

raw sugar

0.967 t

3

Water

610 m

molasses

3.87 t

Bactericides

894.3 kg

filter muds

6.31 t

sodium hypochlorite

73.9 g


NaCl

1502.3 kg

CH4

1914 g

Lime

104.03 kg

N 2O

847 g

Sulphur

24.08 kg

NOx

16.4 kg

H3PO4

0.92 kg

SOx

6.8 kg 482


NaOH

8.19 kg

NMVOC

18.7 g

HCl

248 g

particles

9.1 kg

Emissions to the water DBO5

13.2 g

suspended material

19.8 g

Table 10. Subsystem Distillery. Amounts referred to 100 t of sugarcane. Inputs

Amount

Molasses

3.87 t

natural gas

3

101.97 m 3

Outputs

Amount

alcohol 96 %

1388.49 L

alcohol low grade

35.43 L

Water

162.2 m

alcohol redistilled

41.96 L

H2SO4

33 kg

anhydrous alcohol

886.15 L

Cyclohexane

2.23 kg

fusel

0.74 L

Urea

0.447 kg

vinasses

11518 L

Phosphate

0.298 kg

Emissions to the air CO2

2.48 t

Emissions to the soil sulphates

82.28 kg

total solids

866.42 kg

ammonia

183,29 g

sulphides

16.67 g

potassium

262.65 kg

Case II: Anaerobic digestion in UASB reactors and combustion of mixed raw vinasses + bagasse + RAC

This alternative considers that a certain percentage of the vinasses that leaves the subsystem Distillery is treated in anaerobic reactors UASB-type with the aim of removing the organic load, then sending the output of this reactor to the sugarcane fields for fertigation. The remaining vinasses without treatment are mixed with RAC (agricultural harvest waste) and bagasse, in order to be burnt in a tailored boiler. The calorific power of this mixture is about 4110 kcal/kg related t a blend composition of 50 % bagasse, 30 % RAC and 20 % raw vinasses, in a mass basis. In the anaerobic treatment of vinasses, the volume of vinasses remains almost constant, resulting in a COD removal of 65 % and in BOD renoval of 80 %, as indicated by the works by Mohana et al. (2009), Pant and Adholeya (2007) and Harada et al. (1996). As observed in Table 4, BOD values at the reactor inlet vary from 50,000 to 60,000 ppm, COD values from 110,000 and 190,000, whereas at the outlet, values oscillate between 8,000-10,000 and 45,000-52,000, respectively. Basically two streams leave these reactors: treated vinasses and biogas. For the considered production of ethanol it is generated a flow rate of approximately 2.7 m3 of biogas, which is considered as an air emission, however the possibility of integrate energetically this waste treatment to the sugar-ethanol production process could be studied. 483


Table 11. Characterization of the vinasses that enter and leave the reactor (Mohana et al., 2009) Parameter

Raw vinasses

Treated vinasses

PH

3.0-4.5

7.5-7.8

BOD5 (mg/L)

50,000-60,000

8,000-10,000

COD (mg/L)

110,000-190,000

45,000-52,000

total solids (mg/L)

110,000-190,000

70,000-75,000

total suspended solids (mg/L)

13,000-15,000

38,000-42,000

total dissolved solids (mg/L)

90,000-150,000

30,000-32,000

phenols (mg/L)

8,000-10,000

7,000-8,000

sulphates (mg/L)

7,500-9,000

3,000-5,000

phosphates (mg/L)

2,500-2,700

1,500-1,700

total nitrogen (mg/L)

5,000-7,000

4,000-4,200

Figure 3. Schematic of a UASB reactor.

Table 5 shows the input and output data for the subsystem Distillery. Table 12. Subsystem Distillery. Amounts referred to 100 t of sugarcane. Inputs

Amount

Molasses

3.87 t

natural gas

Outputs

Amount

alcohol 96 %

1388.49 L

101.97 m

alcohol low grade

35.43 L

3

3

Water

162.2 m

alcohol redistilled

41.96 L

H2SO4

33 kg

anhydrous alcohol

886.15 L

Cyclohexane

2.23 kg

fusel

0.74 L

Urea

0.447 kg


Phosphate

0.298 kg

CO2

3.29 t

methane

190.67 kg

Emissions to the soil sulphates

55.13 kg

ammonia

122.8 g 484


sulphides

11.17 g

potassium

175.97 kg

Case III: Concentration to 60 % for combustion in gas natural boilers

With this combined alternative, the goal is that the effluent to the outlet of the reactors UASB enters to an evaporation system to be concentrated; this is done to obtain concentrated vinasses suitable to be burned. During the evaporation of vinasses some water steam is generated while during vinasses combustion potassium ashes are generated, which can be utilized as fertilizers. For Cases II and III, the input and output data of the subsystem Agriculture are the same as those for Case I. The proposed strategy, vinasses concentration using an arrangement of multiple effect evaporators, employs exhaust vapour at 1.5 bar as a heating agent. So as to be able to concentrate 11,978 litres of vinasses from 11.1 % to 60 %, Table 6 shows some relevant values that arise from the mass and energy balances.

Table 13. Balance for vinasses evaporation (Perera, 2009). Item

Volume

vinasses with 11 % solids to concentrate

11,978 kg

evaporated water

9,762 kg

requirements of vapour for heating

1,823 kg

vinasses with 60 % solids concentrated

2,216 kg

It is noteworthy that some contributions mention that vinasses concentration can be only done from a concentration value of 4 % solids to a maximum value of 40 %, by using a five-effect evaporation system (Sowmeyan and Swaminathan, 2008). It is also important to point out that the vinasses concentration and combustion processes removes almost totally the organic load, meeting one of the main objectives of the treatment, which is the weakening of the high pollutant power of the waste. Once the vinasses are concentrated, an alternative fuel is obtained, which can be burnt as concentrated vinasses or mixed with bagasse. It has been considered, from the corresponding energy balances, that 1 kg of bagasse 50 % moisture is energetically equivalent to 1.2 kg of vinasses with 60 % of solids. Table 7 shows some relevant figures for the proposed scheme.

Table 14. Inputs and outputs of the systems for vinasses treatment by means of digestion-concentrationcombustion. Inputs raw vinasses

Outputs

11,518 L

biogas generated in reactors UASB

2.7 m3

methane after biogas purification

1.62 m3

water vapour at 1.5 bar evaporated water

1,823 kg 9,762 kg 485


vinasses with 60 % solids

2,216 kg

Heat energy produced for combustion of concentrated vinasses

6,367 kcal

Among the uses of methane gas, water steam and heat derived from this alternative, it can be mentioned: (i) vapour generation in gas natural boilers; (ii) electricity generation in turbines; (iii) hot water production for pre-heating water feed in boilers, and (iv) electricity generation in gas engines or gas turbines. With this alternative, from the point of view of the mass balance, it is also possible to obtain a high valueadded by-product: a liquid or solid biofertilizer with a high content of potassium. Table 8 shows the inputs and outputs data for the subsystem Distillery. Table 15. Subsystem Distillery. Amounts referred to 100 t of sugarcane. Inputs

Amount

Molasses

3.87 t

natural gas

Outputs

Amount

alcohol 96 %

1388.49 L

121.97 m

alcohol low grade

35.43 L

3

3

Water

163.4 m

alcohol redistilled

41.96 L

H2SO4

33 kg

anhydrous alcohol

886.15 L

cyclohexane

2.23 kg

fusel

0.74 L

urea

0.447 kg


phosphate

0.298 kg

CO2

10.5 t

methane

0.935 t

NOx

0.82 t

Emissions to the soil potassium

170 kg

5 Results

Figure 4. Environmental performance for the subsystem Agriculture, Case I (fertigation).

486


Figure 5. Environmental performance for Agriculture + Mill, Case I (fertigation).

Figure 6. Environmental performance for the global system, Case I (fertigation).

Figure 7. Environmental performance for the global system, Case II (digestion UASB + combustion).

487


Figure 8. Environmental performance for the global system, Case III (digestion + concentration + combustion). The results show, firstly, that the alternatives of fertigation and vinasses treatment with UASB reactor more combustion, i.e. the alternatives I and II, respectively, have the best overall environmental performance. That is not so if the environmental impact is discriminated in different categories. Moreover, the alternative I have the best environmental performance, from the point of view of climate change, based on the balance of greenhouse gases, while the opposite occurs with the alternative III.

6. Conclusions While treatment of vinasses represents no direct economic benefits, it is closely related to the sustainability of the sugar-ethanol production activities. The possibility of achieving an objective view of the impact caused by each of the treatment strategies makes the LCA a valuable and essential support tool for selecting the most appropriate technology. Acknowledgements The authors acknowledge the financial support of the Ministry of Science, Technology and Productive Innovation (Projects PFIP-ESPRO), Council of Science and Technology (Universidad Nacional de Tucumán), and CONICET.

References Cavalett O, Da Cunha MP, Junqueira TL, De Souza Dias MO, De Jesus CDF, Mantelatto PE, Cardoso TF, Franco HCJ, Maciel R, Bonomi A (2011a). Environmental and economic assessment of bioethanol, sugar and bioelectricity production from sugarcane. Chemical Engineering Transactions, 25, 1007-1012. Cavalett O, Junqueira TL, Dias MOS, Jesus CDF, Mantelatto PE, Cunha MP, Franco H, Cardoso T, Maciel R, Rosell C, Bonomi A (2011b). Environmental and economic assessment of sugarcane first generation biorefineries in Brazil. Clean Technologies and Environmental Policy, 1-12. Contreras, A, Rosa, E, Pérez, M, Van Langenhove, H, Dewful, J (2008). Comparative life cycle assessment of four alternatives for using by-products of cane sugar production, Journal of Cleaner Production, 17, 772-779. 488


García CA, Fuentes A, Hennecke A, Riegelhaupt E, Manzini F, Masera O (2011). Life-cycle greenhouse gas emissions and energy balances of sugarcane ethanol production in Mexico. Applied Energy, 88(6), 2088-2097. Harada, H, Uemura, S, Chen, AC, Jayadevan, J (1996). Anaerobic treatment of a recalcitrant distillery wastewater by a thermophilic UASB reactor.Bioresource Technology, 55, 215-221. Luo L, van der Voet E, Huppes G (2009). Life cycle assessment and life cycle costing of bioethanol from sugarcane in Brazil. Renewable and Sustainable Energy Reviews, 13(6-7), 1613-1619. Mele FD, Kostin A, Guillén-Gosálbez G, Jiménez L (2011) Multiobjective Model for More SustainableFuel Supply Chains. A Case Study of the Sugarcane Industry in Argentina. Industrial & Engineering Chem. Res. 50, 4939–4958. Mohana, S, Acharya, B, Madamwar, D (2009).Distillery spent wash: Treatment technologies and potential applications. Journal of Hazardous Materials, 163, 12-25. Nguyen TLT, Gheewala SH (2008). Life cycle assessment of fuel ethanol from cane molasses in Thailand. International Journal of Life Cycle Assessment, 13(4), 301-311. Ometto AR, Hauschild MZ, Roma, WNL (2009) Lifecycle assessment of fuel ethanol from sugarcane inBrazil. Int J Life Cycle Assess 14:236–247. Pant, D, Adholeya, A (2007). Biological approaches for treatment of distillery wastewater: a review. Bioresource Technology, 98, 2321-2334. Perera, JG (2009). Concentración y combustión de vinazas. Informe Técnico de Secretaría de Estado de Gobierno y Justicia - Subsecretaría de Asuntos Técnicos. Renouf MA, Pagan RJ, Wegener MK (2011) Life cycle assessment of Australian sugarcane products witha focus on cane processing. Int J Life Cycle Assess 16:125–137. Roberto A, Zwicky M, Nelson W (2009) Lifecycle assessment of fuel ethanol from sugarcane in Brazil. International Journal of Life Cycle Assessment, 14(3), 236-247. Sánchez, O, Cardona, C, Sánchez, D (2007) Análisis de ciclo de vida y su aplicación a la producción de bioetanol: una aproximación cualitativa, Revista Universidad EAFIT, 43 (146), 59-79. Sowmeyan, R, Swaminathan, G (2008). Effluent treatment process in molasses based distillery industries: a review. Journal of Hazardous Materials, 152, 453-462. Seabra JEA, Macedo IC, Chum HL, Faroni CE, Sarto CA (2011). Life cycle assessment of Brazilian sugarcane products: GHG emissions and energy use. Biofuels, Bioproducts and Biorefining, 5(5), 519-532.

489


Life cycle assessment applied to technology for the remediation of contaminated sites: a case study with chemical oxidation Claudia Echevenguá Teixeira*+ – Rachel Horta Arduin* – Oswaldo Sanchez Junior * – Ana Carolina La Laina Cunha – Alexandre MaximianoΔ * IPT – Instituto de Pesquisas Tecnológicas do Estado de São Paulo – Avenida Professor Almeida Prado, 532 – Cidade Universitária – 05509-901 – São Paulo, SP – Brasil +

UNINOVE – Universidade Nove de Julho – Mestrado Profissional em Gestão Ambiental e Sustentabilidade – GeAS –

Avenida Francisco Matarazzo, 612 – 05001-100 – São Paulo, SP – Brasil Δ

Tecnohidro Projetos Ambientais LTDA

++55 11 3767-4251 [email protected] URL: http://www.ipt.br

Abstract The remediation of contaminated areas comprises the rehabilitation of a region through the removal, containment or reduction of contaminant concentrations. Despite the remediation solve problems related to environmental and public health, the technologies used can cause environmental impacts associated with resource use, emissions and transformation of the area. This case study aimed at quantifying the environmental impacts associated with the treatment of an area contaminated with tetrachloroethene, trichloroethene and 1,1,2,2-tetrachloroethane by chemical oxidation through the life cycle assessment method. The contaminated area is located in the city of São Paulo (Brazil), and had hosted a factory where the main industrial process developed was electroplating. Methods The GaBi 4.0 software was used for modeling the life cycle, and TRACI was the selected method for the life cycle impact assessment once it has been the most widely method used in studies of life cycle assessment applied to remediation technologies. Results Among the environmental impact associated to the process of rehabilitation of the contaminated area, entitled secondary impacts, a high impact associated with soil acidification was noticed due to the pH reduction caused by the addition of oxidizing agents in the treatment. Conclusion The application of LCA in assessing the impact of remediation technologies indicates the most significant environmental impacts of the technologies and thus may foster the development of improvements on the techniques with respect to environmental performance, and also assist in decision making for selection among technologies. Keywords: Remediation of contaminated areas - Chemical oxidation - Sustainable Remediation - Life cycle assessment.

1. Background The deposition of waste and chemicals into the soil and water resources causes negative impacts on human health and the environment. Among the groups of chemicals responsible for actions adverse to health and the environment are organochlorines, polychlorinated biphenyls, phenolic compounds, petroleum hydrocarbons, heavy metals, among others (Teixeira et al. 2012). In the state of São Paulo (Brazil), according to the State Law # 13,577, of July 8, 2009, contaminated area 490


is an area, land, location, installation, construction or improvement containing quantities or concentrations of matter under conditions of causing or that could cause harm to human health, the environment or other good to protect (Conselho Nacional de Meio Ambiente, 2009). In technical terms, the management of contaminated areas is a sequence of steps that aim to identify and establish the extent of contamination and develop recovery actions after confirmation of contamination. The recovery process involves a detailed investigation, risk assessment, remedial investigation, project and implementation of remediation and monitoring (CETESB 2007). The remediation comprises one of the intervention actions for rehabilitation of a contaminated area, which consists of applying techniques, aiming at the removal, containment or reduction of contaminant mass (CONAMA 2009). The remediation of a contaminated area can involve biological processes, thermal, physical and chemical, as, for example, bioremediation, phytoremediation, thermal and chemical treatment, among others (Sharma and Reddy 2004). The adoption of one or a combination of different technologies will depend on the intended use of the contaminated area, the risk assessment, process efficiency, time for decontamination and economic viability. Although the process of rehabilitating a contaminated area solves environmental and public health, it can also create negative environmental impacts (Teixeira et al. 2012). The remediation techniques can last for a long time and are responsible for natural resource consumption, greenhouse gas emissions and effluents, waste generation, land use, among others (Beinat and Nijkamp 1997). In this perspective, in 2006 the Sustainable Remediation Forum (SURF) expanded the dialogue on sustainable remediation, which includes technique or combination of remediation techniques that considers the best combination considering environmental, social and economic factors (Bayer and Finkel 2006). According to a review performed by Cunha et al. (2012), the first life cycle assessment study applied to remediation technologies was conducted in 1999. Some studies have presented discussions regarding the characteristics, difficulties and general structure of LCA applied to remediation technologies (Suer et, 2004, Lemming et al, 2010, Morais and Delerue-Matos, 2010 and Teixeira, 2012). According to the review mentioned above, only the study performed by Cadotte, Deschênes, Samson (2007) evaluated the impacts associated with the application of chemical oxidation. This study aimed to compare the environmental performance of four treatment scenarios, technologies both in situ and ex situ, viable financially, technically and legally, for rehabilitation of an area contaminated by diesel in the ground and in the aquifer. This case study aimed at quantifying the environmental impacts associated with the treatment of an area contaminated with tetrachloroethene, trichloroethene and 1,1,2,2-tetrachloroethane by chemical oxidation. This study is characterized as an exploratory life cycle assessment, oriented to assessing the impacts associated with the preparation, oxidant injection and monitoring phases.

2. Methods The contaminated area hosted a factory located in the southern region of the city of São Paulo, São Paulo state, and occupies approximately 24,000 m2. According to surveys developed in the stage of preliminary evaluation, the main industrial process potentially developed in the area was electroplating. In electroplating process the metal is subjected to several chemical treatments aiming to increase its durability. In order to revitalize the mentioned area for construction of residential buildings (future intended use), a risk assessment to human health was performed and an intervention plan was established based on the procedure described by CETESB in DD 103/2007 (TECNOHIDRO , 2010). According to analytical results of the samples collected in the field area investigated, it was found that the soil had chemicals, but at concentrations that pose no hazard. However, groundwater was affected with high levels of concentration of chemicals belonging to the group of volatile organic compounds as shown in Table 1.

Table 1 - Concentration of contaminants, guiding values and reduction factor Contaminants 1,1,2,2Concentration Tetrachloroethe Tetrachloroetha ne ne Groundwater of the area 1 3500 – 7125,6 188,2 – 34.638 (µg/L) Guiding values for intervention (µg/L) Reduction factor based on risk

Trichloroethen e 382,9 – 7176

0,055 2

40 3

70 3

45

590

590 491


1

Minimum and maximum volume of contaminant detected in one or more samples collected in the sixteen multilevel monitoring wells installed in the area. 2 EPA-Region 9 guiding values for intervention. 3 CETESB guiding values for intervention. From these values, the risk characterization was prepared considering workers and future residents of the building that will be built in the study area for the following exposure scenarios: inhalation of vapors from groundwater in closed and open ambient, dermal contact with groundwater and groundwater ingestion. A partir desses valores, elaborou-se a caracterização do risco considerando trabalhadores e residentes do futuro empreendimento a ser construído na área de estudo, considerando os seguintes cenários de exposição validos: inalação de vapores a partir da água subterrânea em ambientes fechados e abertos, contato dérmico com a água subterrânea, e ingestão de água subterrânea. In this context, to establish actions that minimize or eliminate the potential human health risks identified, an intervention plan was established based on the following intervention actions: remediation for treatment of the groundwater; institutional action with definition of a restriction perimeter for use of the groundwater; environmental monitoring action for verifying the concentrations of residual contaminants in groundwater for a period of two years after the remediation. The possible techniques considered for the remediation area were chemical oxidation using sodium persulfate and chemical reduction with zero-valent iron nanoparticles (EZVI). Regarding the LCA, due to lack of information on the production of zero valent iron nanoparticles in LCA databases, only the impact of the application of chemical oxidation with sodium persulfate was evaluated. The selected method for evaluating the impact of the life cycle was the TRACI and the impact categories considered were global warming potential, ozone depletion potential, acidification potential and eutrophication potential. The method and impact categories were selected based on the high incidence in LCA studies applied to remediation technologies according to the review presented by Teixeira et al. (2012). Gabi 4.0 was the software selected for modeling the lifecycle.

3. Results The functional unit adopted in the study was "management of the groundwater located in an area of 24,000 m2, with depth between 0.9 and 5.0 meters, with a reduction in the concentration factor of 45 for 1,2,2 tetrachloroethane, 590 for tetrachloroethene and 590 trichloroethene in two years". Figure 1 shows the system considered, and the boundaries of the study. The impacts associated with laboratory analyzes and manufacture of the equipment used in the remediation were not considered in the study.

Figure 1 – System Table 2 presents the inputs considered in the life cycle inventory (LCI). It is important to mention that were not considered emissions from the reactions of sodium persulfate with the contaminants in the soil. Table 2 – Lifecycle inventory Inputs

Mass/ Volume

Stages of the system Preparation

Injection

Monitoring

Database

1. Materials 492


Procedure gloves

kg

20,00

PlasticsEurope

Disposable sampler

kg

6,60

PlasticsEurope

Trash bag

kg

2,00

PlasticsEurope

Bubble wrap

kg

2,00

PlasticsEurope

Glassware

kg

4,00

Buwal

Ball valves

kg

27,00

Leather glove

kg

7,50

Tube

kg

252,00

308,00

PE International Especialistas PE: Hans-Jörg Althaus PlasticsEurope

Tube filter

kg

72,00

88,00

Bentonite

kg

900,00

1.100,00

Cement

kg

450,00

550,00

Sand

kg

36,00

44,00

Prefilter

kg

1.350,00

1.650,00

PlasticsEurope Especialistas PE: Roberto Dones Especialistas PE: Tina Künniger Especialistas PE: Roberto Dones PE International

Inlet chamber

kg

54,00

66,00

PE International

kg

78000,00

Water for mixture

L

648.000,00

792.000,00

PE International

Water for washing

L

675,00

825,00

PE International

Fuel (gasoline)

L

2,70

3,30

PE International1

Fuel (diesel) Caption: 1 Brazilian grid

L

4000

55,00

PE International1

2. Oxidant Sodium persulfate

Especialistas PE: Jürgen Sutter

3. Water

4. Fuel

Figure 2 presents the results obtained in the distribution of aspects associated with the impact categories mostly evaluated in LCA studies applied to remediation of contaminated areas (global warming potential, acidification potential, eutrophication potential and ozone depletion potential). Evaluating the other impact categories associated with the TRACI method, others categories presented higher impacts as shown in Figure 3.

493


Figure 2 – TRACI method – Impact categories mostly evaluated in LCA studies for remediation technologies

Figure 3 – TRACI method – Impact categories with greater potential impact

4. Discussion The global warming potential (Figure 2) represents the largest contribution, amounting in all stages of the life cycle of 15,215 kg CO2 equivalent. Emissions are caused by use of fossil fuels and other energy sources necessary for the manufacture of components and materials (preparation stage) and during injection due to the use of diesel in the injection pumps. The acidification potential was also high, totaling at all stages of the life cycle 3175 mol equivalent H +, consequent to the addition of oxidant agents in the treatment and to the generation and disposition of wastes in the manufacture of metal parts, glass and cement. Evaluating all impact categories of the TRACI method (Figure 3), it was also observed that the greatest potential impacts are associated to global warming and acidification. However, the air and water ecotoxicity potentials and smog potential had greater impact than the eutrophication and ozone depletion potentials preselected due to a higher incidence in LCA studies applied to remediation technologies. The air and water ecotoxicity and smog are resulting from the preparation phase, and can be attributed to emissions and waste generation at this stage, which involves, among others, manufacture of metal parts, 494


cement, glass and conformation plastics. Emissions from the reaction of sodium persulfate with the contaminants in the soil were not included in the study, however the authors believe that these issues should be considered in LCA studies applied to remediation technologies, especially knowing that the collection and treatment of gases emitted as a result of the application of remediation technologies is not commonly practiced in remediation of contaminated areas in Brazil. Therefore, it is understood as an opportunity for future work verifying if has a significant difference in the final outcome of the LCA when such emissions are considered. An important issue to be considered is that the environmental impacts associated with the remediation technique is not only a result of the use of materials, equipment and energy, but also of the strategies selected for the interventions. These also end up reflecting the commitments related to availability of funds and time to perform the work. The model adopted should reflect these parameters and mark out the product considered. Another aspect to be considered is how to capture the main inputs for remediation (water and sodium persulfate) and its transportation to the site because it influences the final result of the study since it can introduce considerable impacts on the assessment depending on the logistics considered. In this study we considered the caption of water on site, which is associated with the high incidence of global warming potential in the monitoring phase due to the use of suction pumps.

5. Conclusion The application of LCA in assessing the impact of remediation technologies indicates the most significant environmental impacts of the technologies and thus may foster the development of improvements on the techniques with respect to environmental performance, and also assist in decision making for selection among technologies. Another advantage of using the means of LCA to compare remediation technologies or even different intervention strategies, is that it enables to simulate various scenarios (reflection of intervention strategies), producing more information for foundation of decision making by managers responsible for the enterprise. Aiming to encourage decision-making during the intervention plan elaboration, the LCA must be performed before the selection of remediation technology, as a prospective LCA that allows the assortment of remediation technology based not only on technical aspects and costs.

6. References Bayer P, Finkel M (2006) Life cycle assessment of active and passive groundwater remediation technologies. Journal Of Contaminant Hydrology, Amsterdam, v. 83, n.3/4, p.171-199 Beinat E, Nijkamp P (1997) Environmental rehabilitation: efficiency and effectiveness in soil remediation. Amsterdam: Faculteit der Economische Wetenschappen en Econometric. Cadotte, M., Deschênes, L. & Samson, R. (2007) Selection of a remediation scenario for a diesel-contaminated site using LCA. The International Journal of Life Cycle Assessment. 12 (4), 239-251. Companhia Ambiental do Estado de São Paulo [CETESB] (2007) Decisão de Diretoria nº 103/2007/C/E, de 22 de junho de 2007. Dispõe sobre o procedimento para gerenciamento de áreas contaminadas. Conselho Nacional de Meio Ambiente [CONAMA] (2009) Resolução nº 420, de 28 de dezembro de 2009. Dispõe sobre critérios e valores orientadores de qualidade do solo quanto à presença de substâncias químicas e estabelece diretrizes para o gerenciamento ambiental de áreas contaminadas por essas substâncias em decorrência de atividades antrópicas. La Laina Cunha A C, Arduin RH, Ruiz M, Texeira C E (2012) Análise crítica da aplicação da avaliação do ciclo de vida no contexto de remediação de áreas contaminadas. Anais do III Congresso Brasileiro em Gestão do Ciclo de Vida de Produtos e Serviços. 24-29. Lemming G, Hauschild M Z, Bjerg P L (2010) Life cycle assessment of soil and groundwater remediation technologies: literature review. International Journal of Life Cycle Assessment, v.15, n.1, p.115-127. Morais, S. A. & Delerue-Matos, C. (2010). A perspective on LCA application in site remediation services: Critical review of challenges. Journal of Hazardous Materials, 175 (1-3), 12-22. Oliveira, R. M., Bastos, L. H. P., Dias, A. E. X. O., Silva, S. A., & Moreira, J. C. (2003). Concentração residual de hexaclorociclohexano em área contaminada na Cidade dos Meninos, Duque de Caxias, Rio de Janeiro, Brasil, após tratamento com óxido de cálcio. Cadernos de Saúde Pública. 19 (2), 447-453. Sharma, H. D. & Reddy, K. R. (2004) Geoenvironmental engineering: site remediation, waste containment, and emerging waste management technologies. Hoboken, New Jersey: John Wiley & Sons. Suer, P., Nilsson-Paledal, S., Norrman, J. (2004). LCA for site remediation: a literature review. Soil & Sediment Contamination: an International Journal. 13 (4), 415-425. TECNOHIDRO (2010). Relatório SP20100205 – confidencial. 495


Teixeira, C. E.; Cunha, A. C. L. L.; Arduin, R. H.; Ruiz, M. S. (2012). Avaliação do ciclo de vida (ACV) aplicada a remediação de áreas contaminadas. Revista de Gestão Social e Ambiental, v. 6, p. 3-18.

Acknowledgements The authors acknowledge the support provided by Instituto de Pesquisas Tecnológicas do Estado de São Paulo – IPT, Tecnohidro Projetos Ambientais LTDA and Fundo de Apoio a Pesquisa - FAP/UNINOVE, as well as the financial support provided by Banco Nacional de Desenvolvimento – BNDES through the project "Development and validation of technologies for remediation of soil and groundwater contaminated with organochlorines."

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The need for consequential system modelling in Life Cycle Assessment for robust decision support Bo P. Weidema1 - Miguel Brandão2–- Jannick H. Schmidt1 1

Aalborg University, Denmark

2

International Life Cycle Academy,ESCI, PasseigPujades 1, 08003,Barcelona, Spain

2.-0 LCA consultants

+ 34 931 066799 [email protected] URL: http://ilca.es

Abstract Purpose The purpose of this paper is to review and elucidate on the need for consequential system modelling in life cycle assessment for robust decision support. Methods A range of critical issues that have been claimed to limit the usefulness of consequential LCA is identified and reviewed. For illustrative purposes, the life cycle greenhouse gas emissions of different biofuels estimated via both consequential and attributional system modelling approaches are compared and contrasted. Results Each point of criticism of consequential LCA is evaluated and rebutted. It is found that attributional LCAs consistently underestimate the magnitude of (and hence the impacts related to) indirect land-use changes and those related to biofuel co-products. Conclusions For robust policy support, it is necessary to consider as far as possible all (direct and indirect) potential impacts of product systems, which is core to the concept of non-shifting of burdens in life-cycle thinking. Given that robust methods – such as those embedded in a consequential system modelling approach - already exist to this effect, the normative system modelling choice of consistently excluding these indirect effects in (attributional) LCAs is unjustifiable and will support the wrong decisions. The implication is that the reproducibility, reliability and acceptance of life cycle assessment as a decision-support tool is, hence, compromised. The superiority of consequential LCA over attributional LCA for robust decision support is demonstrated. Key words: attributional LCA, consequential LCA, normative choices, decision support, biofuels, indirect landuse change. It is much more important to be able to survey the set of possible systems approximately than to examine the wrong system exactly. It is better to be approximately right than precisely wrong. Tribus and El-Sayed (1982)

Introduction There are many misconceptions in the LCA community regarding consequential life cycle assessment(CLCA) modelling. This synthesis paper reviews and discusses some of the most common misconceptions related to the nature and use of CLCA and, thereby, highlights the real potential of using CLCA. 498


This paper identifies and assesses some criticismstargeted at CLCA expressed in current literature. In particular, Baitz et al. (2013) express several concerns about the use of CLCA that reflect some of the misconceptions that we are trying to clarify here. The following sectionsfocus on specific arguments that have been put forward, and challenge them, one by one.The misconceptions on completeness, on uncertainty, on market assumptions, and on accountability and incentives, are addressed here. Additional misconceived features erroneously attributed to consequential modelling include lack of representativeness, increased data requirements, higher cost, greater uncertainty, and irrelevant for small changes. Similarly, attributional models are often considered simpler, easier to communicate, and more reproducible. These misconceptions are identified here, but not elaborated upon.Subsequently, a case-study on biofuels is used to illustrate the key differences between these two irreconcilable approaches and implications for robust decision support. Reviewing alternative modelling approaches

The two different approaches are defined in the Shonan Guidance Principles (UNEP/SETAC, 2011). CLCAis a ―system modelling approach in which activities in a product system are linked so that activities are included in the product system to the extent that they are expected to change as a consequence of a change in demand for the functional unit.― Conversely, attributionalLCA is a ―system modellingapproach in which inputs and outputs are attributed to the functional unit of a product system by linking and/or partitioning the unit processes of the system according to a normative rule― (UNEP/SETAC, 2011) [our highlighting]. Figure 1 illustrates the conceptual difference between ALCA and CLCA regarding system delimitation.

Figure 1. The conceptual difference between attributional and consequential LCA. The circles represent the total global environmental exchanges. In the left circle, attributional LCA seeks to cut out the piece with dotted lines that belongs to a specific human activity, e.g. car driving. In the right circle, consequential LCA seeks to capture the change in environmental exchanges that occur as a consequence of adding or removing a specific human activity (Weidema, 2003, p.15). The main differences between attributional and consequential approaches are summarised in Table 1. Further differences and consequential applications can be found (e.g. Abiola et al., 2010; Brandão, 2012; Dalgaard et al., 2008; Earles and Halog, 2011; Ekvall, 2004; Finnveden et al., 2009; Kløverpris et al., 2008; Kløverpris, 2010; Lund et al., 2010; Reinhard and Zah, 2009; Reinhard and Zah, 2011; Sanden and Schmidt, 2007; Schmidt, 2008; Schmidt and Weidema, 2008; Schmidt, 2010; Suh et al., 2010; Thomassen et al., 2008; Weidema et al., 2009). Table 1. Main differences between attributional and consequential modelling ALCA CLCA Standardisation Rule-based (e.g. ILCD ISO 14040/44/49 Handbook) Goal & Scope Descriptive Consequences of changes Completeness / Complete global system of Only affected parts. Only System delimitation activities, but no rebound unconstrained activities 499


Reference flow

Elasticity of supply

effects. Linking of both constrained and unconstrained activities. Produced by scaling the existing average markets and suppliers

Long-term constraints Handling of joint production

Full, except for joint production Ignored Partitioning (Allocation)

Market effects38 Data Uncertainty

Ignored Average More precise, less accurate

Complexity Cost Reproducibility Representativeness and relevance for decision-support

High High Low Low

are linked. Produced by scaling the most likely suppliers to be affected by a change in demand Full, except for constrained supplies Identified / captured Substitution (System expansion) Identified / captured Marginal39 Less precise, but more accurate Low Low High High

Key misconceptions The most important misconceptions related to consequential modelling are discussed here. These are on data requirements and extension of modelled system, on uncertainty and relevance, on market assumptions, and on accountability and incentives. On data requirements and extension of modelled system

Some LCA researchers/practitioners fear that CLCA implies infinitely-extended systems (e.g. Baitz et al., 2013). This may be a misconception stemming from the term ―system expansion‖ which is used in ISO 14044 to describe the procedure where an alternative production route is substituted for each dependent by-product of the system. However, when working with LCA databases that cover the entire economy, the activities to be substituted are already included in the database.Most life cycle inventory database providers put a considerable amount of effort in improving their datasets, both by extending the completeness/coverage of economic processes of/in their database and by improving the quality and representativeness of their datasets. The increased quality of data allows for all first-order substitution effects to be captured without need for adding new data to the database. On uncertainty and relevance

Another issue raised by some LCA researchers/practitioners is that CLCA implies ―growing uncertainties due to assumptions of related or possible consequences" (Baitz et al., 2013)‖. However, ignoring real and relevant consequences does not diminish the uncertainty, but simply ignores or hides it. The quote given above make the point that "it is better to be approximately right than precisely wrong" (Tribus and El-Sayed, 1982). The difference between accuracy and precision is illustrated in Figure 1. The problem is very clearly illustrated in Weidema (2009) using the parable of the "streetlight effect" (e.g. Friedman, 2010), which is a type of observational bias. The parable is told in several ways but includes the following details: An observer sees a drunk man searching for something under a streetlight and asks what the drunk has lost. He says he lost his 38

substititution, income, rebound and other market effects The term marginal, as opposed to average, refers to the effect per unit of a small change in any variable. For example, marginal land, or land on the margin of cultivation, is land that would just become worth farming if output prices rose slightly, or would go out of cultivation if prices fell slightly. The term also refers to productivity (of land, i.e. yield, farm, capital), production, product (e.g. cereal, crop), supply, supplier, producer, source, emissions, models, cost (including social, private, pricing), benefit (including social), revenue, utility, rate (of substitution, transformation, equality, tax), efficiency (of capital), propensity (to consume, import, save), spending, conditions, firm, etc. (Black, 2002) 39

500


keys and they both look under the streetlight together. After a few minutes the observer asks if he is sure he lost them here, and the drunk replies:No, he lost them in the dark alley. The observer asks why he is searching here, and the drunk replies: "This is where the light is." Figure 2explicitly points out the subtle but important difference between accuracy and precision and the importance of not confounding the two.

Figure 2: Precision and accuracy (European Commission, 2010, p. 326) On market assumptions: data, supply elasticity and linking of activities

Some LCA researchers/practitioners express their belief that the main challenge for CLCA is the reliance on uncertain predictions of market effects, apparently failing to understand that any system model necessarily relies on market assumptions. The market delimitations in CLCA are identical to those in ALCA, e.g. that electricity markets are commonly nationally delimited. IfALCA is used for decision support, it is implicitly assumed that all current suppliers to the market will continue to supply the market in proportion to their current production volumes, so that demanding an extra unit of product will lead to the production of one unit of product without any changes in prices and consumption by other market actors, which is often clearly a highly implausible assumption. The use of average data, instead of marginal, is clearly a limitation significant enough for policy-makers to have discarded ALCA for policy support, e.g. in the assessment of the climate impacts of arising from the indirect land-use change effects of biofuels (see e.g. Malins, 2012 and Brander et al. 2009). On accountability and incentives

Some LCA researchers/practitioners claim that CLCA does not address accountabilities appropriately and can provide misleading incentives, but no justification or examples have been provided to support this claim. In reality, it is attributional models that provide misleading incentives because they:  artificially subdivide (i.e. allocate) activities that in real life belong together; 

include activities that cannot contribute to environmental improvements, and ignore real-life consequences and impacts;



leave out environmentally-relevant flows and include irrelevant ones; and



ignore or underestimate uncertainties that can only be quantified by comparison to the consequential results.

Case-study: indirect land-use changes and biofuels A case-study on the indirect land-use change (iLUC) effects ofproducing one tonne of oil equivalent40(toe) of bioethanolin different countries and crop feedstocksis used here for comparing consequential and attributionalmodelling approaches. A consequential approach does not attempt to give an equal share of landuse change to all current land use. Instead, it tries to identify the drivers that actually result in land conversions, without which the land-use change would not have occurred, and ascribe them to these. Conversely, an attributional approach looks at land-use change as a phenomenon that can be ascribed to all crop production from current agricultural land use, so that each occupied hectare is ascribed the same share of the total global land-use change. 40

1 toe = 41.9 GJ 501


Estimating iLUC with a consequential approach

The method by Brandão (2012), adapted from Schmidt (2010), is used here to calculate iLUC. This method takes into account the balance associated with additional production of feed protein and energy arising from biofuel by-products. Figure 3 shows a scenario whereby the additional demand for 1 toe of bioethanol in EU is met through increased imports of maize (aka corn) from France. Assuming that the diverted maize was used for flour, that flour demand remains constant, and that wheat flour substitutes for maize flour, the displaced maize production in France is compensated by extra production of wheat in Canada, resulting in 2.11 ha of iLUC in Canada (the marginal wheat supplier). In addition, accounting for the marginal production of animal feed from the extra Dried Distillers Grains and Solubles (DDGS) results in a net effect of 1.35 ha of iLUC, mainly from Canada (the marginal wheat producer). Figure 4 shows the total land requirements for the production of 1 toe of bioethanol from several regions and crops, estimated with a consequential-modelling approach.

Figure

3:

Wheat

Sugar Beet

Sugar Cane

France

USA

South Africa

Pakistan

Mozambique

Brazil

UK

France

Ukraine

Germany

France

4 3 2 1 0 Canada

ha

1toe extra ethanol demand in EU from French maize

ILUC Land Use

Maize

Figure 4. Land use requirements and indirect land-use change (iLUC) associated with producing 1 toe of bioethanol from a range of feedstocks and origins, calculated with consequential approach. NB: iLUC does not take place in the same country as the origin of the crop/feedstock (Brandão, 2009). Estimating iLUC with an attributional approach

FAOSTAT (2013) estimated that global arable land expanded by around 5.5 Mha between 2008 and 2009 (the year for which the latest data are available). In an attributional approach, this change would be attributed to 502


every existing crop, resulting in 0.004ha of LUC being attributed to each ha of land use. Comparing iLUC results estimated via both approaches

Including iLUC estimated with an attributional approach in Figure 4 would produce no visually-perceptible changes as they are minute. iLUC is significantly greater when calculated with a consequential-modelling (marginal) approach than with an attributional-modelling (average) counterpart. Indeed, while iLUC calculated consequentially is higher than 0.2ha/toe, that calculated atributionally is lower than 0.02ha/toe. Furthermore, iLUC is may often be of a greater magnitude than direct LUC in CLCA, but never in ALCA. Whereas in a consequential approach iLUC is never less than half of direct land use (and sometimes it is much greater than land use, see Figure 4), in an attributional approach less than 0.5% of (i)LUC is attributed to each ha of land use. The difference between 0.5haindirect/ha and 0.004haindirect/ha is greater than three orders of magnitude.

Conclusions and Outlook The case study used here show that an attributional approach shows to consistently underestimate iLUC relative to the alternative consequential approach. The difference is greater than three orders of magnitude and illustrates each of the four misconceptions identified above in relation to decision support for biofuels and climate-change policies. ALCA should not be discussed as an alternative to consequential modelling, which is in practice the only system model that ―describes the environmentally relevant flows to and from a product or process and is therefore the backbone for robust results in practice. Changes in results relate directly to modifications of the technical processes under analysis, uncertainties, or variations in results are understandable and quantifiable over parameter variations and future trends can be addressed via suitable technical scenarios‖ (description of ALCA by Baitz et al., 2013). Academia, industry and governments – and society, at large - can benefit from a consistent application of a consequential system-modelling approach: 1) by obtaining the real information instead of false and malleable information, and 2) from dealing with the real issues and contributing to the long-term societal changes rather than postponing change by focusing on artificial problems.

References Abiola, A., E. S. Fraga and P. Lettieri (2010). Multi-objective design for the consequential life cycle assessment of corn ethanol production. Computer Aided Chemical Engineering. 28: 1309-1314. Baitz et al. (2012) LCA‘s theory and practice: like ebony and ivory living in perfect harmony?International Journal of Life Cycle Assessment.http://www.springerlink.com/content/2166816077516680/ Black, J. (2002). Oxford Dictionary of Economics. Oxford, New York, Oxford University Press. Börjesson, P. and L. M. Tufvesson (2011). "Agricultural crop-based biofuels - resource efficiency and environmental performance including direct land use changes." Journal of Cleaner Production 19(2-3): 108120. Brandão (2009) Assessing the land-use consequences of meeting EU biofuel targets. European Commission Joint Research Centre. Draft Report. Brandão M (2012) Food, Feed, Fuel, Timber or Carbon Sink? Towards Sustainable Land Use: a consequential life cycle approach. PhD thesis. Centre for Environmental Strategy (Division of Civil, Chemical and Environmental Engineering), Faculty of Engineering and Physical Sciences, University of Surrey, UK. 246 pp. Appendices 541 pp. Brander and Wylie (2011) The use of substitution in attributional assessment.http://www.tandfonline.com/doi/pdf/10.1080/20430779.2011.637670

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Dalgaard, R., J. Schmidt, N. Halberg, P. Christensen, M. Thrane and W. Pengue (2008). "LCA of soybean meal." The International Journal of Life Cycle Assessment 13(3): 240-254. Earles and Halog (2011) Consequential life cycle assessment: a review. The International Journal of Life Cycle Assessment 16(5): 445-453. http://www.springerlink.com/content/9325304g17315042/ Ekvall, T., Weidema B.P. (2004). "System boundaries and Input Data in consequential Life Cycle Inventory Analysis." International Journal of Life Cycle Assessment 9(3): 161-171. European Commission (2010).General guide for Life Cycle Assessment - Detailed guidance.International Reference Life Cycle Data System (ILCD) Handbook.Ispra, Joint Research Centre, Institute for Environment and Sustainability. FAOSTAT. Statistical database of the Food and Nations.http://faostat.fao.org. Accessed 14th January 2013.

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Finnveden, G., M. Z. Hauschild, T. Ekvall, J. Guinée, R. Heijungs, S. Hellweg, A. Koehler, D. Pennington and S. Suh (2009). "Recent developments in Life Cycle Assessment." Journal of Environmental Management 91(1): 1-21. Freedman D (August 1, 2010)."The Streetlight Effect". Discover magazine. Freedman D (2010).Wrong: Why Experts Keep Failing Us. Little, Brown and Company. ISBN 0-316-02378-7. Henry, K (2010) Measuring what we do or doing what we measure: Challenges for Australia. Plenary address to the Natsats 2010 Conference.Natstats 2010. 15 September 2010 – 17.September 2010, Sydney. Secretary to the Treasury of the Government of Australia | 16 September 2010. http://www.treasury.gov.au/PublicationsAndMedia/Speeches/2010/Measuring-what-we-do-or-doing-what-wemeasure Kløverpris, J., H. Wenzel and P. Nielsen (2008). "Life cycle inventory modelling of land use induced by crop consumption. Part 1: Conceptual analysis and methodological proposal." The International Journal of Life Cycle Assessment 13(1): 13-21. Kløverpris, J. H. (2010). Consequential Life Cycle Inventory Modelling of Land Use Induced by Crop Consumption.Department of Management Engineering.Lyngby, Technical University of Denmark. Industrial PhD: 168. Lund, H., B. Mathiesen, P. Christensen and J. Schmidt (2010). "Energy system analysis of marginal electricity supply in consequential LCA." The International Journal of Life Cycle Assessment. Malins, C. (2012), A model-based quantitative assessment of the carbon benefits of introducing iLUC factors in the European Renewable Energy Directive. GCB Bioenergy. doi: 10.1111/j.1757-1707.2012.01207.x Pelletier and Tyedmers (2011) plus response, plus response.An Ecological Economic Critique of the Use of Market Information in Life Cycle Assessment Research.http://onlinelibrary.wiley.com/doi/10.1111/j.15309290.2011.00337.x/abstract Read, C. (1898). Logic: deductive and inductive. London, Simpkin. Reap et al. (2008) A survey of unresolved problems in life cycle assessment. Part 1: goal and scope and inventory analysis. http://www.springerlink.com/content/514424221v18t3r7/ Reinhard, J. and R. Zah (2009). "Global environmental consequences of increased biodiesel consumption in Switzerland: consequential life cycle assessment." Journal of Cleaner Production 17(Supplement 1): S46. Chapter V – Discussion and Conclusions 241 504


Reinhard, J. and R. Zah (2011). "Consequential life cycle assessment of the environmental impacts of an increased rapemethylester (RME) production in Switzerland." Biomass and Bioenergy In Press, Corrected Proof. Sanden, B. A. and M. Karlstrom (2007). "Positive and negative feedback in consequential life-cycle assessment." Journal of Cleaner Production 15(15): 1469. Schmidt, J. (2007). Life Cycle Assessment of Rapessed Oil and Palm Oil.Department of Development and Planning. Aalborg, University of Aalborg. PhD: 362. Schmidt, J. (2008). "System delimitation in agricultural consequential LCA." The International Journal of Life Cycle Assessment 13(4): 350. Schmidt, J. and B. Weidema (2008). "Shift in the marginal supply of vegetable oil." The International Journal of Life Cycle Assessment 13(3): 235-239. Schmidt, J. (2010). "Comparative life cycle assessment of rapeseed oil and palm oil." The International Journal of Life Cycle Assessment 15(2): 183-197. Suh, S., B. Weidema, J. H. Schmidt and R. Heijungs (2010). "Generalized Make and Use Framework for Allocation in Life Cycle Assessment." Journal of Industrial Ecology 14(2): 335-353. Thomassen et al. (2008) Attributional and consequential LCA of milk production. The International Journal of Life Cycle Assessment 13(4): 339. http://www.springerlink.com/content/f5239h5q15224696/ Tribus, M. and Y. El-Sayed (1982).Introduction to Thermoeconomics. Cambridge, Massachusetts, Compendium, MIT UNEP/SETAC (2011) Global Guidance Principles for Life Cycle Assessment Databases: A Basis for Greener Processes and Products. 'Shonan Guidance Principles'. Weidema, B. P. (2009), Avoiding or Ignoring Uncertainty. Journal of Industrial Ecology, 13(3): 354– 356.doi: 10.1111/j.1530-9290.2009.00132.x. http://onlinelibrary.wiley.com/doi/10.1111/j.15309290.2009.00132.x/abstract Weidema, B. P., T. Ekval and R. Heijungs (2009). Guidelines for application of deepened and broadened LCA. Deliverable D18 of work package 5 of the CALCAS project.http://fr1.estis.net/includes/file.asp?site=calcas&file=7F2938F9-09CD-409F-9D70-767169EC8AA9 Weidema, B. P. and J. H. Schmidt (2010). "Avoiding Allocation in Life Cycle Assessment Revisited." Journal of Industrial Ecology 14(2): 192.http://onlinelibrary.wiley.com/doi/10.1111/j.1530-9290.2010.00236.x/abstract Weidema (2011) Stepping Stones From Life Cycle Assessment to Adjacent Assessment Techniques.Journal of Industrial Ecology.http://onlinelibrary.wiley.com/doi/10.1111/j.1530-9290.2011.00391.x/abstract Weidema (2011) Stepping Stones From Life Cycle Assessment to Adjacent Assessment Techniques http://onlinelibrary.wiley.com/doi/10.1111/j.1530-9290.2011.00391.x/abstract Weidema B P. (2003).Market information in life cycle assessment. Copenhagen: Danish Environmental Protection Agency. (Environmental Project no. 863). http://www2.mst.dk/Udgiv/publications/2003/87-7972-991-6/pdf/87-7972-992-4.pdf Zamagni et al (2012a) Finding Life Cycle Assessment Research Direction with the Aid of Meta-Analysis. http://onlinelibrary.wiley.com/doi/10.1111/j.1530-9290.2012.00467.x/abstract Zamagni et al. (2012b) Lights and http://www.springerlink.com/content/7141344788620059/

shadows

in

consequential

LCA.

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LCADB.sudoe: Life Cycle Inventories database of the southwest of Europe Carles M. Gasol1,2* – Esther Sanyé1 – Elsa Valencia2 – Joan Rieradevall1,2,3 – Eva Sevigné1– Julia Martínez-Blanco1 –Gara Villalba1,3– Xavier Font 3,4 - Adriana Artola 3,4 – Antoni Sanchez3,4–Assumpció Anton1,5 – Pere Muñoz1,5 – Juan Ignacio Montero5 – Cyril Arnoult6,7 – Philippe Roux7 – Marilys Pradel8–VeroniqueBellon Maurel7, – Montse Núñez7,9– Arnaud Hélias6,9 – Ana Claudia Dias10 – Luis Arroja10– Miquel Rigola11–Quim Comas11 –Serní Morera11– Xavier Gabarrell1,2,3 1

Sostenipra (UAB-IRTA-Inèdit). Institute of EnvironmentalScience and Technology (ICTA), UniversitatAutònoma de

Barcelona (UAB), 08193 Bellaterra, Barcelona, Spain 2

Inèdit Innovaciós.l.,carretera de Cabrils Km2, 08348,Cabrils (Barcelona),Spain.

Phone: +34 93 753 29 15 E-mail: [email protected] URL: http://www.ineditinnova.com, http://www.sostenipra.cat, http://lcadb.sudoe.ecotech.cat/, 3

Chemical EngineeringDepartment, Universitat Autónoma de Barcelona (UAB), 08193 Bellaterra, Barcelona, Spain.

4

Grup de Recerca en Compostatge (GICOM). 3Chemical EngineeringDepartment, Universitat Autónoma de Barcelona

(UAB), 08193 Bellaterra, Barcelona, Spain. 5

Institut de Recerca i TecnologiaAgroalimentàries (IRTA). Carretera de Cabrils. km 2. 08348. Barcelona, Spain

6

Montpellier SupAgro, 2 place Pierre Viala, F-34060 Montpellier Cedex 2, France7 Irstea, ITAP Research Unit, team

ELSA (Environmental Lifecycle & Sustainability Assessment) 361 rue JF Breton, 34196 Montpellier, France 7

Irstea, ITAP Research Unit. 361 rue JF Breton 34196 Montpellier, France

8

Irstea, TSCF Research Unit, Domaine des Palaquins, F-03150 Montoldre, France

9

INRA, UR0050, Laboratoire de Biotechnologie de l‘Environnement, Avenue des Etangs, Narbonne, F-11100, France

10

Universidad de Aveiro, Aveiro, Portugal

11

Universitat de Girona, Girona, Spain

507


Abstract Purpose. During the life cycle inventory (LCI) phase the data collection and modelling of the system (e.g. product) is performed. This is usually done in line with the goal definition and meeting the requirements derived from the scope phase. Afterwards, these LCI results are the input to the subsequent LCIA phase (ILCD 2010). The objective of this paper is to present the design and structure of the LCADB.sudoe database and explain how to share Life Cycle Inventory datasets in the on-line application, available in the website: http://lcadb.sudoe.ecotech.cat/ Method. The database presented in this chapter is being developed in the context of the Ecotech-Sudoe project (ECOTECH-SUDOE project, soe2/P2/E377). An on-line application and a protocol of dataset compilation were developed to facilitate the introduction of datasets of primary data by different users (LCA practitioners, decision-makers in companies and designers and engineering‘s of products, processes and services, etc.). A dataset questionnaire was created considering the criteria proposed by the in ecoeditor of ecoinvent database and the ILCD editor of ELCD database. Hence, compatibility between data of the LCADB.sudoe, ecoinvent and ELCD requirements was ensured. The partners collaborating in the EcotechSudoe project and institutions of Spanish LCA Network have shared datasets in this first version of LCADB.Sudoe The last step of the process includes the review of the LCI by an expert committee before its publication. Results. The entire database contains initially more than 100 dataset about some productive sectors of SUDOE area tested at user level for more than 20 research institutions. For their scope, the inventories that we can expect to find in these databases, are related to important and specific productive sectors of SUDOE area such as agriculture, fishing, cities, energy production, manufacture process, services, transport, use & consumption, waste treatment and water among others. An expert committee that it will review and publish the datasets has been configured with editors of Spain, France, Portugal&Brasil. They are specialist in the Life Cycle Assessment research in each productive sector and the responsibles of securing a good quality in the data shared in datasets. Conclusions. As indicated by a great scientific team in LCA (Rebitzer et al, 2004), ―the databases that provide LCA inventories of high quality data (transparent and coherent) of frequent use products are useful and necessary, especially for development of products in a company‖. In this sense some experiences and databases have been developed: LCI (Life Cycle Inventory) of PNUMA/SETAC which had establish a revised database and updated (ELCD) or ecoinvent, among others (Gabi Team, LCAFoods…). LCADB.sudoe aims to complete and share life cycle datasets with other existing life cycle databases with the final objective of improving productive sectors of the Sudoe area (South of France, Spain and Portugal). Finally the LCADB.sudoe aims to be a replicable and useful data management tool for other LCA databases initiatives especially in Latin America.

KEY WORDS: dataset, Ecotech, life cycle assessment, life cycle inventories, sostenipra

Introduction Data collection is one of the main parts to perform a Life Cycle Inventory (LCI) of the Life Cycle Assessment (LCA) method (ISO, 2006). During the last decades, some databases were created in order to compile consistent and transparent LCI data, such as the ecoinvent (Frischneckt et al., 2007) and the ELCD (JRC, 2012) databases at Europe level. However, there is a lack of specific databases for the SUDOE area that include local inventory data to avoid the uncertainty of using European data (e.g. specific process and products such as: wine, cork, oil, fish, etc., differences in technology level, efficiency or transport distances). Therefore, a LCI database for the Sudoe area could provide geographic specific LCI with quality data that also focuses on themes with special importance in this regional area (e.g. water). 508


Purpose The main objective of this project is to develop a common database for LCI in the SUDOE region (Spain, Portugal and France) useful for projects and collaboration between the participant institutions. Furthermore LCADB.sudoe aims to be a replicable and useful data management tool for other LCA databases initiatives especially in Latin America. There are 10 topics covered in the database, as summarized in table 1.

Method In order to fulfil this goal a manual for users and revisers was written. These manuals contain useful and detailed information about how to upload the datasets, an explanation of the required data for each field and how to use the tool. Each Inventory has 4 sections: 1. INFORMATION: includes all the relevant information of the project such as name, type, ID (NACE code), system boundaries (flow chart), etc. 2. LCI & VALIDATION: includes data about the methodology and approach used. 3. ADMINISTRATIVE: includes the contact details of the author for the purpose of giving feedback, asking for supporting documentation or information. 4. INVENTORY: includes all the flows and components of the process. The users of the database creation process are  User: normal users (can consult public datasets) or qualified as a collaborator (can consult either public and private datasets) 

Reviser: researchers that carry out the content review



Editor: expert committee of researchers of the SUDOE area and partners of the ECOTECH project that decided if the dataset can be published or not.

The steps for the creation of the database are shown in Figure 1.
1.



User: creates an inventory model Model: a flow model of the technical system is made using data on inputs and outputs. The flow model includes the activities that are going to be assessed in the relevant supply chain and gives a clear picture of the technical system boundaries.



Data: The next step is to collect the input and output data needed for the construction of the model for all activities within the system boundary (including from the supply chain), the data should be relevant for the study and simplified when possible.



Verification: When the LCI is completed, meaning all the data is compiled the data should be verified in terms of its consistency with the methodology and with the goal/scope of the overall project, the data quality should meet basic statistical requirements such as: accuracy, representativeness, completeness and precision/uncertainty of the inventory [European Commission, 2010].



Format: The data is uploaded in the online format through the website http://lcadb.sudoe.ecotech.cat/

2. The dataset is uploaded into the system and sent to the editor of the topic with the aim to be reviewed. The editors of the project organize the different LCIs, as they are the link between the revisers and users. 3. The reviewer receives the information and evaluates the content of the inventory; the points to be assessed are: complete submission of the data in each step (i.e. all required fields completed), nomenclature according the elemental flows from the International Reference Life Cycle Data System (ILCD – [1]), and the 509


correct and sufficient information for the LCI. 4. The reviewer should contact the database author using the contact data provided in the forma for feedback or in the case that further documentation and/or complementary information is required. 5. The editor, previous communication with reviewer, sets the status of the process: accepted, need to be improved, rejected. In any case the reviser notifies the editor about this decision. 6. The editor makes the inventory accessible to the partners and other users of the LCIDB. The editor takes into consideration the user‘s request regarding the publication of the database (public, public for partners, private, etc.)

Results The results of this phase were the development of the LCADB website as a tool for the database creation. The LCADB website has been tested, at user level, for more than 20 research institutions. Another result was the 2 manuals for a proper use of the tool: one for users and another for revisers & editor. The user‘s manual also defines the quality guidelines of the LCI data collection and the system modeling, that were created according to the ecoinvent (Weidema et al., 2012) and the ELCD databases (JRC, 2012) The expert‘s manual includes a list of the revisers per category and a checklist in order to review each of the phases of the process in the LCI and assure its completeness. Currently the database contains more than 100 different datasets and it is provided that the total quantity rises due to the increasing participation of SUDOE & Spanish LCA research institutions in LCADB.sudoe. The inventories categories covered now are (Figure 2): Agriculture (72%), followed by Manufacture processes (9%), Water (5%), Energy production (4%), Cities (3%), Services (3%), Waste (2%), Fishing (2%) and Waste (1%).
The inventories accessibility is 61% public, 22% public for partners and 17% private. It is also important to note that half of the inventories uploaded (48%), had been published in journals or in other scientific resources and therefore were evaluated through peer-review process.

Conclusions The LCADB.sudoe is a useful tool for compiling consistent and transparent data of local and specific products & processes of the Sudoe area. Regarding to complete and share life cycle inventory (LCI) data with other existing life cycle databases like ecoinvent and ELCD, we are still working to develop an informatics data management tool capable to export and import datasets. An expert committee with high expertise in LCA has been configured for the review process to secure a high quality, uniform and useful LCI database. This project fulfils its final objective of improving productive sectors of the Sudoe area (South of France, Spain and Portugal) by giving access to useful information about processes in 10 different categories to LCA practitioners, decision-makers in companies and designers and engineering‘s of products, processes and services. The database is oriented to public and private participants, national and international. Furthermore LCADB.sudoe aims to be a replicable and useful data management tool for other LCA databases initiatives especially in Latin America.

Acknowledgment Interregional cooperation which enabled this work was done with the support of Ecotech-Sudoe project (International Network on LCA and Ecodesign for Eco-innovation - SOE2/P2/E377) funded by the EU Interreg IV B Sudoe Program. Philippe Roux, VérniqueBellon, Cyril Arnoult, MontseNuñez, Arnaud Hélias are members of the ELSA research group and they thank their colleagues from their relevant advice (Elsa: Environmental Life Cycle & Sustainability Assessment, www.elsa-lca.org).

510


References Frischknecht R, Jungbluth N, Althaus H-J, Doka G, Dones R, Hischier R, Hellweg S, Nemecek T, Rebitzer G, Spielmann M (2007) Overview and Methodology. Final report ecoinvent data v2.0, No. 1.Swiss Centre for Life Cycle Inventories, Dübendorf. European Commission - Joint Research Centre (2010) International Reference Life Cycle Data System (ILCD) Handbook - General guide for Life Cycle Assessment - Detailed guidance. Publications Office of the European Union, Luxemburg. Weidema BP, Bauer C, Hischier R, Mutel C, Nemecek T, Reinhard J, Vadenbo CO, Wernet G (2012). Overview and methodology.Data quality guideline for the ecoinvent database version 3.Swiss Centre for Life Cycle Inventories, Dübendorf. ISO (2006) ISO 14044:2006 Environmental management -- Life cycle assessment -- Requirements and guidelines.International Organization for Standardization, Geneva. JRC (2012).ELCD database – online application.European Commission - Joint Research Centre. Available on: http://lca.jrc.ec.europa.eu/lcainfohub/datasetArea.vm. Accessed 20 October 2012.

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Tables And Figures Table 1. Description of topics, scope and examples of specific datasets available on LCADB.sudoe. Topic Scope of topic Specific products or process for SUDOE area Agriculture Intensive, Extensive, Fruit, Products as: tomato, fruits, cork. Horticulture… Process as: machinery, agrochemicals doses, operation times, diesel. Fishing

Fishery

Cities

Construction, street furniture

Energy Production Waste treatment

Renewable & Nonrenewable Municipal waste treatment

Water

Municipal Waste Water treatment and Rainwater use

Manufacture process Services Transport Use and Consumption

Products as: tune. Process as: machinery, operation times, diesel. mobility,

General

Products: construction building materials, infrastructures for recharging electrical car, street furniture products Products as: biomass production, energy crops. Technologies and infrastructures available of SUDOE area for municipal waste treatment Technologies and infrastructures available of SUDOE area to treat and use several kinds of water

All the production and services process involved in productive sectors of SUDOE regions.

Figure 1. LCI database creation process.

Figure 2.Number of datasets compiled in dataset categories until November 2012

512


513


LCIA

514


Life Cycle Impact Assessment on the land use impacts and application of Geographic Information Systems Natalia Crespo Mendes* – Ana Laura Raymundo Pavan – Cristiane Bueno – Giulio de Manincor Capestrani–Paula Madeira Gomes – Marcelo Montaño – Aldo Roberto Ometto * Universidade de São Paulo. Avenida Trabalhador Sãocarlense, 400. São Carlos – São Paulo – Brasil – CEP 13566-590.

++55 16 33738608 [email protected] URL: http://www.prod.eesc.usp.br/sep/

Abstract Objectives: To promote a survey of the main Life Cycle Impact Assessment (LCIA) methods, currently used worldwide, classifying their evaluative characteristics in order to obtain an overview of the applicability of such methods on the land use impacts for Latin American countries. This paper also aims to discuss how these impacts have been evaluated in LCIA and how the integration of Geographic Information Systems (GIS) as an element of methodological support can occur. Methods: The main LCIA methods were classified according to the level of assessment, geographical scope, impact categories addressed, normalization and weighting methods. Thus it was possible to identify which methods are applicable in Latin America to assess the impacts on land use. In parallel a literature review was conducted about the land use impacts which data were analyzed according to the following parameters: applied method, midpoint and endpoint indicators, impact characterization model and inventory data required for calculation. From this information was verified how GIS can support the Life Cycle Assessment (LCA). Results and discussion: The methods, in general, are aimed at specific regional contexts of European, Asian and North American countries, which limits their coverage of application to different locations worldwide. The land use impacts are assessed by the methods CML 2002, Eco-indicator 99, Ecological Scarcity, Imapct 2002+, LIME, LUCAS, ReCiPe, TRACI e IMPACT World+ but only CML 2002 and IMPACT World + are considered to be global application methods. It can be noticed that land use is usually evaluated based on net primary productivity, species richness of vascular plants, life support functions, biodiversity, resource depletion, exploitation of natural resources, land use efficiency and rehabilitation degree of the land. Conclusions: Since most of LCIA methodologies are specifically developed to Europe, Asia and North America, one solution identified for evaluation in Latin American countries is the use of global coverage application methods. Further possibility relates to the adaptation or development of methodologies aimed specifically at the Latin American context of application, and the integration with Geographic Information Systems is suggested in this research as a promising field. Keywords: Life Cycle Assessment, Life Cycle Impact Assessment, Land Use, Geographic Information Systems.

Introduction The Life Cycle Assessment (LCA) is a methodology used to assess the potential environmental impacts of a product system throughout its life cycle. This practice includes goal and scope definition, inventory analysis, impact assessment and interpretation of the results. Among the phases of a LCA study, the Life Cycle Impact Assessment (LCIA) is the one which uses impact categories and category indicators to assess the significance of environmental interventions within the Life Cycle Inventory (LCI) (Udo de Haes et al, 2002; ABNT, 2009). According to NBR 14044 (ABNT, 2009), the LCIA has the following mandatory steps: a) selection of impact categories, category indicators and characterization models; b) classification of inventory results according to the selected categories, and c) characterization of the aspect valuation, according to its magnitude 515


in relation to the impact. There are also optional steps such as normalization, weighting and grouping, and techniques for data quality analysis. Many LCIA methods have been developed and applied to LCA studies, such as CML 2002, Eco Indicator 99, EDIP 2003, EPS, IMPACT 2002 +, LIME, LUCAS, ReCiPeand TRACI, however, none of these methods is internationally accepted according to the requirements of ISO, and the LCA practitioner has no guidelines when choosing between characterization models and factors, which for some impact categories provide very different results when applied (Hauschild et al, 2012). Most of these methods have a specific impact category to assess impacts related to land use, commonly called Land Use category. However, the approaches of land use as well as its impact category definition are issues that should be studied and discussed, since these impacts are related to others LCA categories. Land use change impacts reflects on the biotic diversity, influence the degradation of soil and water, contributes to the local and regional climate change, as well as global climate change. The land use is often approached as a natural resource that is unavailable for other purposes. Thus, the impacts ofland use reflect the damage to ecosystems due to the effects of occupation and transformation of land (Brentrup et al., 2002; Nguyen; Hermansen; Mogensen, 2010; Gallego et al, 2011). The term land occupation can be defined as the maintenance of an area in a particular state over a particular time period. The term transformation refers to the conversion of land from one state to another (EC-JRC, 2010b). Some approaches present land use related to biodiversity, considering the number of species affected (Canals; Romanya; Cowell, 2007; Schmidt, 2008) or even related to land degradation due to human use, e. g. agriculture and industry (Lindeijer; Alfers, 2001; Brentrup et al., 2004b). In some studies land use is treated as a parameter of climate change category. Kim, Jimenez-Gonzalez and Dale (2009), Kristensen et al. (2011); Lechon, Cabal and Saez (2011); and Reinhardt and Von Falkenstein (2011) consider the effect of land use changes in the evaluation of greenhouse gases emissions. These effects on climate change are considered due to albedo change or changes in CO 2, N2O or CH4 balances. The impacts of land use are highly dependent on the location of the system under study. Many biogeographic factors such as landscape, weather patterns, vegetation and a variety of soil properties determine the severity of environmental effects. Thus, the accuracy of LCA to assess the life cycle of products and services is limited due to the absence of site-specific data. In this sense the use of Geographic Information Systems (GIS) can act as an element of methodological support in order to overcome the issues related to the spatial aspect of the impacts assessed in the LCIA. Syrrakou, Yanoulis and Skordilis (2001) point out the advantages in environmental decision-making possible by the combination of the LCA‘s holistic view with the visualization power of GIS. The authors also emphasize that the application of GIS in LCA studies enables consider specific regional information while optimizing the LCIA, especially the management of the end of the product chain. Thus, this paper aims to discuss the applicability of the main LCIA methods and models currently used for the impact characterization of land use and how Geographic Information Systems (GIS) can be integrated as an element of methodological support to the LCA.

Methodology The methodological procedures used in this paper can be divided into three main stages, namely: A) Survey of the main Life Cycle Impact Assessment (LCIA) methods currently used We performed a literature review based on the methods outlined by the International Reference Life Cycle Data System (ILCD) Handbook – Analysis of existing Environmental Impact Assessment Methodologies for use in Life Cycle Assessment – Background document (EC-JRC, 2010a) and in publications of the UNEP program Life Cycle Initiative, referring to the Life Cycle Impact Assessment stage (UNEP, 2010). The LCIA methods were analyzed according to the following parameters: 

Impact Categories: Analysis of the impact categories addressed by each method;



Evaluation level: Assigning levels of impact assessment as midpoint, endpoint or combined (midpoint / endpoint) to the impact categories addressed by each method;



Scope of application: Determination of the regional coverage of the impact categories of each specific method; 516




Normalization Method: Description of the normalization methodologies presented by the LCIA methods;



Weighting Method: Description of the weighting methodologies presented by the LCIA methods; Among the considered methods we have selected only those which comprise the Land Use impact

category. From this selection the possible methods to be applied in Latin America were identified. B) Analysis of the land use impact approach during the LCIA stage Developed based on material already elaborated this stage of the study comprises a literature review with an exploratory character. The models were analyzed according to the following parameters:  Method applied in the LCIA: Method for assessing the potential environmental impacts from emissions and resource use that can be attributed to specific products in Life Cycle Assessments. 

Impact category indicator: Quantifiable representation of an impact category.



Category endpoint: The category endpoint is an attribute or aspect of natural environment, human health, or resources, identifying an environmental issue giving cause for concern.



Impact characterization model: A set of principles, models and characterization factors that enable the calculation of the characterization results for a certain impact category.



Inventory data required for calculation.

C) Discussion on the integration of Geographic Information Systems (GIS) as a methodological support tool in LCA. This step was jointly developed with the previous one to identify initiatives to implement GIS in the assessment of impacts related to land use in LCA, and also the possible contributions of GIS for LCIA methods.

Results Main LCIA methods

The main LCIA methods addressed in this paper are: Eco-indicator 99 (Goedkoop and Spriensma, 2000), EDIP 97 (Hauschild and Wenzel, 1998), EDIP 2003 (Hauschild and Potting, 2005), EPS 2000 (Steen, 1999a, b), CML 2002 (Guinée et al, 2002), Impact 2002+ (Jolliet et al, 2003), LIME (Itsubo et al, 2004), LUCAS (TOFFOLETTO et al, 2007), ReCiPe (GOEDKOOP et al, 2009), Ecological Scarcity (Frischknecht, 2006), TRACI (Bare et al, 2003), MEEuP (Kemna et al, 2005) and IMPACT World+(IMPACT World+, 2012). After analyzing the first parameter "impact categories" it was possible to identify the methods which evaluate land use impacts. These methods are shown in Table 1 along with the results obtained for the other parameters: evaluation level, scope of application, normalization and weighting methods. Table 1 – LCIA methods which evaluate the land use category. Assessment parameters LCIA Evaluation Scope of Methods Normalization Method Level Application Baseline global CML 2002

Midpoint

Global

normalization factors available for 1990 and

Weighting Method

No baseline method is proposed for weighting.

517


1995 as aggregate annual world interventions or per capita as the annual interventions of an average world citizen. Background spreadsheet available so that normalization factors can be adapted for other methods than baseline methods and for new data developments. Similar normalization factors for the Netherlands and WestEurope are available for extensions (sensitivity analyses). Three options: 1. Panel method is used for default weights European normalization Eco-indicator 99

data are calculated with Endpoint

Switzerland

the method for each area of protection (damage category).

2. Weighting triangle has been developed for decision-making without explicit weighting (i.e. equal weighting) 3. Some authors proposed monetization methods, but these are not widely used.

Ecological Scarcity

Impact 2002+

Normalization applied by Endpoint

Switzerland

dividing by 2004 emission flows.

Combined

Europe

Weighting applied by multiplying by the square of the ratio of actual flow/critical flow.

Normalization factors for

No specific weighting

Europe available for

developed. As a default,

2000 as annual impact

the weighting factors can

scores for an average

be taken as equal,

citizen for all impact

assuming that overall

categories at midpoint

present European

and damage levels.

damage on human health 518


is comparable to impact on ecosystems and to climate change and resources impacts.

LIME

Combined

Japan

No normalization

For weighting, societal

needed, as monetization

costs (in Yen) are used to

is applied at the endpoint

combine the four

level.

safeguard subjects.

It is determined by the ratio of the impact per unit of emission divided by the total impact of all LUCAS

Midpoint

Canada

substances contributing to the specific impact


category, per person. Normalization factors are currently being updated. Three methods are developed: 1. For endpoints a manual for panel

ReCiPe

Combined

Europe

Normalisation data are

weighting is available,

available for Europe and

but no operational

the world in year 2000,

generic weighting set

for 16 midpoint

have been developed

categories and for the

2. For the midpoints a

three endpoint

monetisation method on

categories.

the basis of prevention

Normalisation data on

costs is provided.

land transformation and

3. For endpoints a

fresh water depletion are

monetisation on the basis

not included.

of damage costs is provided. The weighting triangle can be used at the endpoint level.

No baseline method is TRACI

Midpoint

United States

proposed for normalization.

IMPACT World+

Midpoint

Global


No baseline method is

No baseline method is

proposed for

proposed for weighting. 519


normalization. Land use impacts

Regarding the assessment of land use it was possible to identify someauthors who worked with LCIA methods known scientific and internationally, as: Panichelli, Dauriat and Gnansounou (2009), Brandão, Mila I Canals and Clift (2011) and Gallego et al (2011) that used the CML methodology; TRACI was used by Curran (2004); Morais, Mata and Ferreira (2010) the EcoIndicator 99; and Nguyen, Hermansen and Mogensen (2010) EDIP 97. Others authors have developed or adapted assessment models for land use, which will be discussed below. The results were organized in chronological order and respecting the parameters previously set. In a study of Brentrup et al. (2004a) a new LCA method specifically tailored to crop production systems was used in a case study in order to investigate the environmental impact of different N fertilizer rates in winter wheat production. In this study the land use was evaluated and defined as the degradation of natural land due to human utilization for agriculture, housing, roads, industry etc. Hence the authors estimated the Naturalness Degradation Potential (NDP) including the area used for a certain period of time and the intensity of land use. Thus, to calculate the NDP, the model used multiply the land area used for a certain period of time (in m2× year/ton grain) and the characterization factor for a specific type of land use (intensive arable). The study includes the normalization step, which the results for the impact categories deal with effects on natural ecosystems and human health following by the weighting step based on the distance-to-target principle (Brentrup et al., 2003apud Brentrup et al. 2004a). Each normalized indicator value is multiplied by a weighting factor, which represents the potential of the respective impact category to harm resources, natural ecosystems and human health. In the study two separate indicators result from the weighting step: the aggregated resource depletion indicator (RDI) and the aggregated environmental indicator (EcoX). Due to the lack of suitable models that are currently available, Toffoletto et al. (2007) develop an LCIA method by adapting existing LCIA models to the Canadian context named LUCAS. The model selected in LUCAS for land use is based on work by Weidema et al. (2001apud Toffoletto et al, 2007) which take into account both impacts related to Biodiversity and those related to Life Support Functions (LSF). Net Primary Production (NPP) which is defined as the net carbon uptake of the ecosystem over time is the indicator for the LSF of natural systems. Regarding biodiversity the indicator is given by the multiplication of Species richness of the ecosystem (or number of species by surface area), Inherent ecosystem scarcity (ES), Ecosystem vulnerability (EV) and those normalization factors. In the study vascular plants are used as proxy for species richness. Furthermore, characterization factors for each of the 15 terrestrial Canadian ecozones were calculated and when ecozone data were not available, biome data were used in the calculation procedures. In the following year, the study published by Schmidt (2008) develops a method for LCIA that links the land use with biodiversity, focusing on species richness of vascular plants which can be determined from species area curves. The indicator is calculated as the multiplication of occupied area, the number of species affected per standard area (100 m2), the duration of occupation and renaturalisation from transformation, and a factor for ecosystem vulnerability. The entry to the LCI applied by the author was based on land use types, since it is the most common and the required data for are the affected area and the time of occupation. In short, the article proposes an LCIA-method which is applicable on the global scale and is not limited by divisions of categories of land use types. With the aim of fill up the important gap in LCIA of land use Liu et al. (2010) developed a model with Chinese characterization factors for quantify the damages to environment by land use in terms of change in net primary productivity (NPP) of ecosystem. The method comprises the forms of land utilization divided into two aspects involving long-term use of land, namely ―land occupation‖, and the change of land properties, namely ―land transformation‖. The characterization factors of both land occupation and land transformation were calculated using (i) Chinese empirical information on the indicator NPP; (ii) land quality change during the land use duration; (iii) occupation and transformation areas; and (iv) occupation and restore durations. Moreover, the authors considered Damage to the ecosystem as the endpoint category. Garrigues et al (2012) review land use impact assessment in LCA and states that it refers to impacts on land quality, that is ―in the sense of fulfillment of the land functions related to safeguard subjects to be protected by humans ‖(Milà i Canals et al., 2007). This statement implies quantifying land use in units that vary according to the functions of interest of different users. The authors emphasize the importance of developing indicators for soil quality. Thus, the LCI data needed to evaluate involve the amount of occupation, rehabilitated area and Soil Organic Matter (SOM). The authors highlight the need of aggregating several soilrelated impacts into a single midpoint indicator of impact on soil quality. As a midpoint indicator, it would feed into an endpoint indicator such as ―Damage to ecosystem diversity‖. A single indicator of impact on soil quality has not yet been developed because of the difficulty in aggregating processes such as erosion, SOM 520


change, and compaction into a single measure. In the assessment of land use, specific data are usually required for analysis in LCIA as the area occupied by the production processes, period during which follows the occupation of land, and quantitative description of the occupation and transformation processes (characteristics of the land use before, during and after activity). The last item represents one of the problems regarding the information gathering on land transformation processes at a given location. Moreover, information on the number of species affected, Net Primary Productivity and soil characteristics can be difficult to access in countries where the use of LCA is still incipient. In this context, the Figure 1 summarizes the information that GIS can provide at the LCIstage, and the motives for using GIS in LCA studies are shown in Table 2.

Figure 1: Information that GIS can provide at the LCI stage. Table 2 – Motives for using GIS in LCA studies Motives for using GIS in LCA studies Reference

Approach

Saad, et al (2011) Land Occupation and Transformation

Motivation

Expected results

Mapping the differences in Verification of the spatial severity of environmental impact variability of the impacts of between the scenarios using land use generic characterization factors and with local specificities

Beck, et al (2011)

Producing reliable data in Improved database structures appropriate geographical scale for the LANCA tool, increasing and allows the creation of medium the accuracy and reliability characteristic values for any area of interest in LCA

Geyer, et al (2010)

Generates a list of land parcels that, if used for planting biomass crops, would reach a production target previously established

Biodiversity

The comparison of data on crop, regional characteristics, soil productivity and specific habitats, enabling the assessment of impacts over the biodiversity caused by monoculture farming for ethanol production

521


Núñez, et al (2010) Desertification

Crossing information on aridity, erosion, overexploitation of aquifers and risk of fire (each with Allows the production of its own weighting scale), with the impacts scenarios for geographic location, and desertification spatiotemporal distributions of activity, and plotting by overlapping layers

Discussion In most cases the LCIA methods currently used to assess the environmental impacts associated with land use have impact categories labeled as "land use" or "land occupation". However, some particularities were identified for each method with regard to this approach. CML 2002 besides addressing the "land use" category also covers categories as "loss of life support function" and "biodiversity loss", all with global scope of application. The Ecological Scarcity method presents such category as "loss of biodiversity by land occupation", and "emissions to land", both directed to application in Switzerland. LIME presents the category "land use", and also features the categories "terrestrial biodiversity" and "aquatic biodiversity," specific to the Japanese context. ReCiPe is a method which allows the evaluation of land use by different categories such as "agricultural land use" and "urban land use" besides the impact category "natural land transformation". It is noteworthy that the EPS 2000 is not among the methods that have a category of impact assessment for land use, but such method has a category developed to analyze the proportion of species extinction in Sweden. From the results obtained in the second stage of this article, on the approach to land use in LCA studies, it is possible to determine the correlation between impacts associated with land use, biodiversity loss and life support functions. Biodiversity and life support functions, which in some methods appear as categories of impact evaluated separately, may still be considered indicators of land use in other studies, demonstrating the absence of a consensus on the concepts and a standard methodology for assessing these impacts. Regarding the scope of application of the LCIA methods, it is understood that only the methods classified as global are applicable in Latin American countries, such as Brazil. In this context, among the main LCIA methods currently used, only the methods CML 2002 and IMPACT World + are indicated to evaluate the land use impacts, anywhere in the world. The method IMPACT World + was included in this study once it has been recently launched in May 2012 by a research team composed of experts from other LCIA methods mentioned above.IMPACT World + has been developed in response to the need for a regionalized impact assessment. The method provides factors for each continent and assesses regionally any geo-referenced emission or resource use, and uncertainties include information covering both the spatial variability and the uncertainties related to the model (IMPACT World+, 2012). In addition,in a recent study of Hauschild et al. (2012) to identify the best among existingcharacterization models, the authors concluded that the model of Milà i Canals et al. (2007), which applies the indicatorsoil organic matter, is recommendedforcharacterizing land use effects at midpoint. The model is considered by the authors as well applicable for agro andforest systems but it must be applied with caution. Once it constitutes a powerful set of tools for collecting, storing, processing and visualizing spatial data, GIS can be integrated into LCA studies in order to support the evaluation of land use impacts. As an example, it is observed that in many analyzed models data are used on the net primary productivity. However, for the modeling of primary productivity of an ecosystem is necessary to understand the bio-physicochemical relationships between soil, vegetation and atmosphere. These issues, which may be complex in a LCA study, would be solved through the integration of GIS tools in the evaluation.

522


Conclusions As regards the applicability of the LCIA methods in Latin America, it is recommended to use those whose range of application is global. It was found that the assessment of impacts related to land use, life support function and biodiversity are interrelated, however, there is no consensus on how such evaluation should be performed. Also, there are many conceptual issues that should be discussed in further works about the term land use itself and the category definition. Regarding the processing capacity that supports sophisticated models, the existence of new experimental data from remote sensing and the various possible spatial analyzes through GIS, it becomes evident the demand for a methodology integrating GIS and LCA subsidizing more reliable and accurate studies. Since the approach of land use impacts in LCA depends on the amount and the quality information about the studied areas, the survey of inventory data can assist the fusion of LCA models with GIS.

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Goedkoop, M. J., Spriensma, R. (2000). Eco-indicator 99, a damage oriented method for lifecycle impact assessment, methodology report (update April 2000) Guinée, J. B. et al (2002). Handbook on life cycle assessment: operational guide to the ISO standards. Series: eco-efficiency in industry and science. Kluwer Academic Publishers, Dordrecht. Hauschild, M. Z. et al (2012): Identifying best existing practice for characterization modeling in life cycle impact assessment. Int J Life Cycle Assess. DOI 10.1007/s11367-012-0489-5. Hauschild, M,; Potting, J. (2005) Spatial differentiation in life cycle impact assessment — the EDIP2003 methodology. Environmental News no. 80. The Danish Ministry of the Environment, Environmental Protection Agency, Copenhagen. Hauschild, M.Z.; Wenzel, H. (1998). Environmental assessment of products. Vol. 2 - Scientific background, 565 pp. Chapman & Hall, United Kingdom, Kluwer Academic Publishers, Hingham, MA. USA. ISBN 0412 80810 2. 1998. IMPACT WORLD+. At http://www.impactworldplus.org/en/presentation.php Accessed May 2012. Itsubo, N.; Sakagami, M.; Washida, T.; Kokubu K,; Inaba, A. (2004). Weighting across safeguard subjects for LCIA through the application of conjoint analysis. Int J Life Cycle Assess 9(3):196 – 205 Jolliet O, Margni M, Charles R, Humbert S, Payet J, Rebitzer G, Rosenbaum R (2003) IMPACT 2002+: a new life cycle impact assessment methodology. Int J Life Cycle Assess 8(6):324 –330. Kemna, R. et al (2005).MEEuP – The methodology Report. EC, Brussels. (Final version, Delft 28-11-2005) Kim, S.; Jimenez-Gonzalez, C.; Dale, B. E. (2009). Enzymes for pharmaceutical applications-a cradle-to-gate life cycle assessment. International Journal of Life Cycle Assessment, v. 14, n. 5, p. 392-400, Jul 2009. Kristensen, T. et al. Effect of production system and farming strategy on greenhouse gas emissions from commercial dairy farms in a life cycle approach. Livestock Science, v. 140, n. 1-3, p. 136-148, 2011. 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Assessment of land use impacts on soil ecological functions: development of spatially differentiated characterization factors within a Canadian context. (L. M. Canals, Ed.) Springer-Verlag, 198-211, 2011. Schmidt, J. H. Development of LCIA characterisation factors for land use impacts on biodiversity. Journal of Cleaner Production, v. 16, n. 18, p. 1929-1942, 2008. Steen, B. (1999a). A systematic approach to environmental priority strategies in product development (EPS). Version 2000-general system characteristics; CPM report 1999:4, Chalmers University of Technology, Gothenburg, Sweden. Steen, B. (1999b) A systematic approach to environmental priority strategies in product development (EPS). Version 2000-models and data of the default method; CPM report 1999:5, Chalmers University of Technology, Gothenburg, Sweden. Syrrakou, H.; Yainoulis, P.; Skordilis, A. (2001). Environmental decision-making using GIS and LCA. In: International Conference on Environmental Science and Technology, VII, 2001, Ermoupolis, Syros island, Greece. Anais… At < http://www.srcosmos.gr/srcosmos/showpub.aspx?aa=4560f>. Accessed August 2012. Toffoletto, L. et al. (2007). LUCAS - A new LCIA method used for a Canadian-specific context. International Journal of Life Cycle Assessment, v. 12, n. 2, p. 93-102, Mar 2007. Udo de Haes, H. A. et al. (2002). Life-Cycle Impact Assessment: Striving towards Best Practice. Society of 524


Environmental Toxicology and Chemistry (SETAC). ISBN 1-880611-54-6, 2002. United Nations Environment Programme – UNEP (2010). Life Cycle Impact Assessment Programme. Life Cycle Initiative. July 2010. At (Accessed June 2011).

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Incorporation Of Risks Analysis Into The Lca Methodology: Challenges In Petroleum Production Caldeira-Pires, A.1 – Deutsch, L.2 1

Department of Mechanical Engineering, University of Brasília.

Campus Universitário Darcy Ribeiro, ZIP 70910-900, Brasília, DF [email protected] 2 Department of Mechanical Engineering, University of Brasília. Campus Universitário Darcy Ribeiro, ZIP 70910-900, Brasília, DF [email protected]

Abstract PurposeThis paper is aimed at discussing aspects related to the frameworks of Life Cycle Assessment and Risks Assessment and their relevance in mitigating environmental impacts. Due to difficulties related to deadline, costs and legal requirements, entrepreneurs have elected one method or the other. This can lead to the adoption of inadequate strategies in a scenario of intensive climatic changes and increasing political and social concerns related to the sustainability of economic growth. Material and MethodsThe use of both methods enables a comprehensive understanding on the impacts ensuing from industrial processes, since the Life Cycle Assessment is concerned with deterministic events (chronic pollution) and the Risks Assessment focuses on probabilistic events (acute pollution), thus being supplementary one another. The unification of the aforementioned assessments frameworks is presented as an alternative to mitigate impacts ensuing from chronic and acute pollutions, and events like those in Bhopal, Fukushima, with Piper Alpha platform, or with the Exxon Valdez oil tanker, thus justifying this initiative. Results and discussionThe proposed framework is applied on the three-phase separation process (petroleum, gas and water) of an offshore platform, using secondary data and the software GaBi 4 (Educational version) in the analysis of different scenarios, thus evidencing its feasibility. Conclusion Based on this analysis, new studies are recommended to improve the method and to build a framework that is easily understood and applied. Keywords:Life Cycle Assessment; Risks Assessment; Monte Carlo Method; Environmental Risks; Mitigation; Petroleum Production.

1.

Introduction

Yeung et al (2011) state that technological and economic development has followed the history of humanity, generating a wide range of pollutants that, in turn, have led to alarming levels of environmental degradation, as observed all over the world.Developing preventive strategies is crucial to environmental conservation, considering that both in environmental and economic lights it is better safe than sorry (Burztyn 1994).That is why Sonneman et al (2004) make reference to the importance of introducing environmental considerations in all aspects and stages of the industrial practices, thus recommending the assessment of impacts caused by chronic and acute pollutions. In order to present the main issues, a brief discussion about Life Cycle Assessment, Risk Assessment and Offshore Petroleum Exploitation is performed:

1.1 Life Cycle Assessment

According to ISO14044 (2009) the Life Cycle Assessment (LCA) focuses on environmental aspects and 526


potential impacts like the use of resources and consequences of releases in environment throughout a product life cycle – from crib to grave.The LCA allows for evaluating environmental impacts through: 

Compilation of inflows and outflows (mass and energetic flows) belonging to a Product System (PS);



Assessment of potential environmental impacts associated to inflows and outflows; and,



Interpretation of findings during the inventory analysis and impacts assessment in relation to the objectives of the studies.

According to Curran (1999), the concept of life cycle has expanded and is now considered to be a core piece to reach more comprehensive objectives, like sustainability. According to Heijungs et al (2010), the scope, boundaries, depth, extension and level of details in the analysis depend on the intended topic and use. However, like any other technique on environmental impact assessment, the LCA bears limitations and uncertainties esteeming from undue handling or interpretation of the data collected, inconsistent selections of the analysis objectives and scope, among other factors (Finnveden et al 2009).The lack of space and time dimensions in the LCA also introduces uncertainty to the results of the analyses (ISO14040 2009). 1.2 Risk Assessment

The Risk Assessment (RA) could be defined as an integrated analysis of the risk inherent to a product, system or plant, and its relevance in an appropriate context.It could also be defined as a scientific process where dangers inherent to processes are estimated as risks, and evaluated in a qualitative and quantitative way (Royal Society 1992).Sonnemann (2004) states that the purpose or objective when carrying out a RAused to be mainly focused on examining the effect of given events on human health.This concept has developed and now it places more emphasis on all kinds of environmental damages.It is a critical and essential part of any decision-making process, and should provide sound grounds to the assessment of potential environmental risk (Darbra et al 2008; Flemstron et al 2004).Please find below the main terms and concepts used by the RA: Box 01:Main terms and concepts used in Risk Assessment Term

Concept

Risk

Combination between probability – or frequency – of the occurrence of a danger defined and magnitude of the consequences of that occurrence.

Impact

Degree of the risk consequence: tolerable or intolerable. It sets out the actions on acceptance, mitigation, modifications or abandonment of the process.

Probability

Philosophical and mathematical concept that allows for quantifying uncertainty, enabling its measurement, analysis and use to make forecasts or to guide interventions.

Uncertainty

Lack of knowledge about the value of a parameter.

Source: Darbra et al (2008), Castro et al (2005), Flemstrom et al (2004) and Philippi Jr. et al (2004). According to Darbra et al (2008) and Philippi Jr. et al (2004) environmental data many times are uncertain, vague and incomplete, so that imprecision is associated to any study in this field. In the assessment of environmental risks, uncertainty may ensue from randomness, be due to the variability of phenomena, or esteem from incompleteness when data or data sources are contaminated by uncertainty, and due to the role played by human judgment in the process when subjectivity is present. 1.3 Offshore Petroleum Exploitation

Air, water and energy are vital ingredients to human life. The demand for energy, notably after the Industrial Revolution, has led to the use of coal, gas and, above all, petroleum that has been the prevailing fuel in the last 50 years (Haug 2011). Jointly with its byproducts like gas, diesel oil, naftas, etc., petroleum has supported the world energetic matrix, and contributes to economic growth (ANEEL 2008). Most of the petroleum produced in Brazil is extracted from maritime fields where, sometimes, the offshore production systems are in charge of primary processing. Processing is required since the in-naturapetroleum is typically composed by oily, water and gaseous fractions, associated or not to the oily phase, additionally to other impurities (Silveira 2006). The FPSO (Floating Production Storage and Offloading) platforms have capacity to receive the in-natura petroleum and separate the fractions of oil, gas, water and other contaminants. That prevents problems of corrosion, incrustation and waste caused by some contaminants, and the over-dimensioning of pumping and storage 527


systems (Devold 2006). Only oil and gas bear economic interest to industry, and are stored for further use. Water is returned to the environment, after being adjusted to the standards established (CONAMA 1986). ISO 17776 (2000) does not distinguish danger or risk directly associated to the separation process, approaching the FPSO structure in a general way. In this situation, the Monte Carlo Method is recommended to define the probability of events that are not covered by the traditional statistical methods.

2.

Material and Methods

Mattheus et al (2002) state that LCA and RA are mutually complementary, despite the different focuses of both frameworks:

Box 02:Conceptual differences between Life Cycle Assessment and Risk Assessment Life Cycle Assessment

Risk Assessment

Focused on product

Focused on process

Disregards the time dimension (permanent regime)

Demands time considerations (transient regime)

No space dimension

Requires space dimension

Source: Mattheus et al (2002) and the authors.

In a graphic way, differences could be represented as follows:

Figure 01: Conceptual differences between Life Cycle Assessment and Risk Assessment

Source: the authors (2012).

The LCA recommends observing a data collection time span long enough to attenuate abnormal behaviors such as machine stoppages or process disturbances (Ferreira, 2004), where line C represents this impact, i.e., chronic pollution. The RA is concerned with abnormalities along time caused by endogenous or exogenous factors, which are represented by peaks A and B and should be analyzed isolated. These are events of acute pollution, whose impact is measured in term of losses (lives, environmental degradation, monetary values, etc.) (Flemstrom et al, 2004). The conceptual

528


differences impair the simplesum of the LCA and RA findings; however, one can think about a unified process. To that, one should: 

For a Product System (PS): observe its geographic location;



For the Process Units (PU) granularity in a PS: highlight those presenting important risk;



Evaluate all operational scenarios to the PS along time, considering endogenous and exogenous risk factors.

The different PU‘s that make up a PS stand for stages of the production process where the inflows (mass and energy) are modified to produce intermediary and final products, and emissions to the environment (outflow). Heijungs et al (2002) propose a matrix approach to solve the PS, where the occurrence of processes is determined simultaneously rather than sequentially. This P matrix could be represented as follows:

𝑃=

𝑎 𝑡𝑒𝑐𝑕𝑛𝑜𝑙𝑜𝑔𝑖𝑐𝑎𝑙 𝑚𝑎𝑡𝑟𝑖𝑥 𝑏 𝑒𝑛𝑣𝑖𝑟𝑜𝑛𝑚𝑒𝑛𝑡𝑎𝑙 𝑖𝑛𝑡𝑒𝑟𝑣𝑒𝑛𝑡𝑖𝑜𝑛 𝑚𝑎𝑡𝑟𝑖𝑥

=

𝑎𝑖,𝑗 ⋯ ⋯ 𝑎𝑖+1,𝑗 𝑏𝑖,𝑗 ⋯ ⋯ 𝑏𝑖+1,𝑗

⋯ ⋯ ⋯ ⋯ ⋯ ⋯ ⋯ ⋯

⋯ ⋯ ⋯ ⋯ ⋯ ⋯ ⋯ ⋯

𝑎𝑖,𝑗 +𝑛 ⋯ ⋯ 𝑎𝑖+𝑛,𝑗 +𝑛 𝑏𝑖,𝑗 +1 ⋯ ⋯ 𝑏𝑖+𝑛,𝑗 +𝑛

(01)

Equation 01: Technological matrix and intervention matrix

Source: Heijings et al (2002). P matrix is made up by two main segments: the technological matrix (a) where elements ai,,j disclose the inflow and outflow of the product i of a process j, where processes are being run in constant conditions; and by the environmental interventions matrix (b), where elements bi,,j disclose the quantity of pollutants or natural resources ireleased or consumed by process j during the operation time in which process ai,,j is specified.

2.1

Case of test – Process of separating oil, gas and water in offshore platform

The separation of fractions of oil, gas and water in gross petroleum is one of the major tasks of a FPSO. According to Sant‘Anna (2005), separation can take place in twophases (free-water knockouts – FWKO) when gas fraction is insignificant, or in three phases when the gas volume is important. Figure 02 depicts a typical three-phase separator:

Figure 02: Schematic model of a three-phase separator Source: Sant‘Anna (2005)

A separator is a complex set of reservoirs, ducts, heaters, heat exchangers, valves, pressurizers, displays, sensors, etc. In this context, petroleum is subjected to a set of interventions regarding the inflow speed, pressure, temperature and composition, being added with agents that could contribute to improve the separation 529


of fractions. The petroleum stays at least four minutes in the separator - time enough to the first separation of gas fraction by gravity. One or more separators can work simultaneously, depending on the volume of petroleum. For example, the FPSO Seillean, working in the Jubarte field, has two sets of separators with total capacity of up to 60 thousand barrels/day, initially serving four flow wells. The separators process, on average, 7m3/minute, with capacity of up to 30m3 for residence (EIA, 2004). After separation, the gas can be used as fuel to the equipment on the platform, be discharged (burn in the flare) or stored, like oil, for further relief. After being decontaminated, water is discharged in the ocean. The case study aimed at determining the environmental impact of the oil, gas and water separation process. The separator model and inflows/outflows were based on literature data. Environmental impacts were estimated based on the LCA, pursuant to ISO14040. The LCA was carried out in two phases: objective and scope and LCI. It employed the gate-to-gate approach, being limited to the boundaries of the system, separation process, gas burn, oil storage, and water discharge. All data used are secondary, and esteem from specialized literature. A young well was considered, with average composition of 70% of oil, 20% of gas and 10% of water and other contaminants. The table below discloses the composition used for inflows and outflows:

Composition of inflows/outflows Inflows

Outflows

Offshore petroleum

Gas

Oil

Comp.

%

Comp.

%

Butane

0,005

x

0,005

Carbon Dioxide

0,002

x

0,002

Decane

Water

Comp.

%

0,075

x

0,075

Dodecane

0,113

x

0,113

Ethane

0,019

Heptane

0,045

x

0,045

Hexane

0,04

x

0,012

x

0,028

Isobutene

0,005

x

0,005

Isopentane

0,017

x

0,0051

x

0,119

Methane

0,138

x

0,138

Nonane

0,075

x

0,075

Octane

0,075

x

0,075

1-Tridecane

0,189

x

0,189

Pentane

0,017

x

0,0051

x

0,0119

Propane

0,015

x

0,015

Ocean Water

0,17

x

Comp.

%

x

0,17

0,019

Table 01: Composition of an offshore petroleum flow Source: Sant‘Anna (2005) and other authors.

Two scenarios were selected to the impact analysis: normal operation and accident with leakage of 100% of the petroleum and water. In all cases, 100% of the gas is burnt. To the permanent regime, total mass flows of about 7m3 were considered, while to the simulation of accident the total flow was 30m3 (volume stores in the threephase separator). To each scenario, the software GaBi 4 (Educational Version) was used to identify environmental impacts, in independent executions. In both cases the same categories of impact were selected, and the results achieved are shown below: 530


Impact Categories

Permanent Regime

Accident

Edip1997 - Global Warming Potential (GWP 100 years)

1,4153x105 Kg.CO2equiv

6,0755x105 Kg.CO2 equiv.

Edip1997 - Photochemical Ozone Formation – impact on human health and materials

0,23733 pers/ppm/hours

1,2264 pers/ppm/hours

Edip1997 - Ecotoxicity water

1,6876x108 m3 water

7,2442x108 m3 water

Table 02: Results achieved in the test case

Source: the authors (2012).

3.

Discussion

In an industrial process, flammable materials and other contaminants are part of transformation processes that operate in conditions very close to the security limits. The installation complexity, kind of material processed and exogenous factors add new dangers to those inherent to the process. The LCA cannot capture these scenarios, thus demanding the use of RA techniques. However, in the case of accidents the spaces neighboring the point of origin of the event are affected. A discussion on the risks and probabilities associated to the scenarios of danger allows the identification of the mass volumes that make up such neighborhood with a reasonable degree of security. The matrix technique proposed by Heijungs at al (2002) is adequate to depict the scenarios of operation in permanent regime, and to accept new data ensuing from a probabilistic event. Therefore, this event becomes a disturbance in one or more processes of the matrix, which can be solved to identify the environmental impacts. The case of test performed, although missing the aforementioned matrix, disclosed that a same set of flows can allow for the calculation of impacts, changing volumes in a simulation of accident.

4.

Conclusion

Bursztyn (1994) emphasizes that the tools for environmental management do not offer accurate scientific solutions, but significantly contribute to the decision-making process. Incorporating RA aspects into the LCA contributes to improve the information generated, simplifies processes, and enables entrepreneurs, government and the society to save time and resources. The proposal herein is consistent to that and proved to be promising, although needing to be deepened. Measuring probabilistic risks is a field yet to be studied, and its final incorporation to the LCA should surely provide a framework responsive to the social and economic demands of our times.

5.

References

ANEEL – Agência Nacional de Energia Elétrica (2008) Derivados de petróleo. Atlas de Energia Elétrica no Brasil, 3a ed. 159 p. Bursztyn MAA (1994) Gestão Ambiental: instrumentos e práticas. IBAMA. Castro CM, Peixoto MNO, Pires do Rio GA (2005) Riscos Ambientais e Geografia: conceituações, abordagens e escalas. Anuário de Geociências – UFRJ, 28:11-30. CONAMA – Conselho Nacional do Meio Ambiente (1986) Resolução n. 20/1986. DiárioOficial da União. Curran M (1999) The Status of LCA in USA.Int J. LCA, 4(3):123-124. Landsberg, Germany: Ecomed.

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Darbra RM, Eljarrat E, Barceló D (2008) How to measure uncertainties in environmental risk assessment. Trends in Analytical Chemistry, 27(4):377-385. Devold H (2006) Oil and Gas Production Handbook – an introduction to oil and gas production.ABB ATPA OilandGas, Oslo Edition 1.3, 84 p. Ferreira JVR (2004) Gestão Ambiental – Análise do Ciclo de Vida dos Produtos. InstitutoPolitécnico de Viseu. Finnveden G, Hauschild MZ, Ekvall T, Guinée J, Heijungs R, Hellweg S, Koehler A, Pennington D, Suh S (2009) Recent developments in Life Cycle Assessment. Journal of Environmental Management, 91:1-21. Flemstrom K, Carlson R, Erixon M (2004) Relationships between Life Cycle Assessment and Risk Assessment – Potentials and Obstacles. Industrial Environmental Informatics (IMI), Chalmers University of Technology, Suécia. Haug M (2011) Clean Energy and international oil.Oxford Review of Economic Policy. 27(1): 92-116. Heijungs R, Suh S (2002) The Computacional Structure of Life Cycle Assessment.Eco-efficiency in Industry and Science.Kluwer Academic Publishers, 241 p. Heijungs R, Huppes G, Guinée JB (2010) Life Cycle Assessment and sustainability analysis of products, materials and technologies. Towards a scientific framework for sustainability life cycle analysis. Polymer Degradation and Stability, 95:422-428. ISO 14040 (2009) Gestão Ambiental – Avaliação do ciclo de vida – Princípios e estrutura. ABNT. ISO 14044 (2009) Gestão Ambiental – Avaliação do ciclo de vida – Requisitos e orientações. ABNT. ISO 17776 (2000) Petroleum and natural gas industries – offshore production installations – Guidelines on tools and techniques for hazard identification and risk assessment. Matthews H, Scott L, Lester MH (2002) Life Cycle Assessment: A Challenge for Risk Analysts. RiskAnalysis, 22(5):853-860. Philippi Jr. A, Romero MA, Bruna GC (2004) Curso de Gestão Ambiental. USP – FAU, Núcleo de Informações em Saúde Ambiental, Editora Manole, 1045 p. Royal Society (2004) Risk – Analysis, perception and management.Reportof a Royal SocietyGroup. Sant‘Anna AA (2005) Simulação de processamento de gás natural em plataforma offshore.UFRJ/EQ. Silveira MACR (2006) Controle de um processo de tratamento primário de petróleo. Dissertação – UFRJ – COPPE. Sonnemann G, Castells F, Schumacher M (2004) Integrated Life-Cycle and Risk Assessment for Industrial Processes. Advanced Methods in Resource and Waste Management Series, 2 – Lewis Publishers – CRC Press Company LLC. Yeung DWK.,Petrosyan, LA (2011) Collaborative Environmental Management. Subgame Consistent Economic Optimization. Static & Dynamic Game Theory: Foundations & Applications.

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LCM and Eco-efficiency

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Development of a methodology for the integration of nutritional and environmental aspects for sustainable food consumption Melanie Haupt* – Neus Sanjuan1 – Javier Ribal2 – Gabriela Clemente1 – Purificación García-Segovia3 * ETH Zurich, Institute of Environmental Engineering, Schafmattstrasse 6, 8093 Zurich, Switzerland 1

ASPA Group.Departament de Tecnologiad‘Aliments.UniversitatPolitècnica de València. Camí de Vera s/n 46022

València. Spain. 2

Departamentd‘EconomiaiCiènciesSocials. Universitat Politècnica de València. Camí de Vera s/n 46022 València. Spain

3

Departament de Tecnologiad‘Aliments.UniversitatPolitècnica de València. Camí de Vera s/n 46022 València. Spain.

Purpose The study aims to develop a methodology to integrate nutritional and environmental aspects of food products into a single indicator. The eco-nutritional-efficiency will aggregate the different dimensions in a unique value to support decision processes of governments, companies and consumers. To provide a non-subjective weighting index, the nonparametric technique data envelopment analysis (DEA) is used. A case study comparing four dietary habits and combinations thereof, consisting of Spanish products, is used to validate the methodology.

Methods A ratio ―nutritional performance/carbon footprint‖ was estimated for 256 daily menus. Carbon footprint (CFP) was obtained from literature. Where no data for Spain was available, the modular method for the extrapolation of crop LCA (MEXALCA) was used for regionalisation. The functional units of literature data were standardised regarding transport and processing. All menus were normalised to 2000 kcal. Macronutrients (fat, proteins and carbohydrates) were used to assess the nutritional performance. To integrate nutritional aspects and CFP two models were developed using DEA. Model 1 focused on the nutrient content. Whereas model 2 took into account the recommended daily intake in order to assess the compliance of each menu with the health guidelines. The eco-nutritional-efficiency ranged between 0 and 1, 1 being efficient.

Results and discussion The CFP of all menus varied between 2.02 and 5.16 kg CO2-eq. Within the group of 256 daily menus, 29 were healthy. The results of the case study showed a high relative eco-nutritional-efficiency of the vegetarian menus, followed by the mediterranean. The vegetarian lunch, including vegetal proteins, was present in all efficient menus. Western dietary habits performed worst due to a high CFP arising from meat consumption. Econutritional-efficiencies between 0.42 and 1 (model 2) showed a potential CFP reduction of 60%. The efficiencies for healthy menus were higher when model 2 was applied. Both models showed a high correlation between the eco-nutritional-efficiency and the CFP.

Conclusion Model 2 focused more strongly on nutritional values and should therefore be preferred and further developed. But while LCA offers a tool to measure environmental performance, no standardized measure for nutritional performance exists. Further investigation and methodological development is needed. The result of DEA, a data based approach, depends largely on its input. To include more products and impact categories, further 534


work should be invested in compiling food LCA. In addition, micronutrients should be considered. Key words: Eco-nutritional-efficiency, data envelopment analysis (DEA), life cycle assessment (LCA), diet, carbon footprint (CFP), sustainability.

1. Introduction The food sector contributes 15-30% to the environmental impact caused by European consumption (Tukker and Janses, 2006; Garnett, 2008). For this and due to the high degree of personal choice and possible day-today selection, food represents a good opportunity for consumers to influence their personal impact (Weber et al., 2008). Several studies investigated the relationship of food and environmental impact (Gerbens-Leenes and Nonhebel, 2002; Carlsson-Kanyama et al., 2003; Reijnders and Soret, 2003). But a comparison between products must also encompass aspects such as nutritional value. One way to tackle the nutritional aspect of foods is to study diets or meals (Saxe et al., 2012;Stehfest et al., 2009; Marlow et al., 2009). Vieux et al. (2012) show that health and environmental effects are not necessarily convergent. Thus, it would be interesting to integrate the nutritional content of diets and their environmental impact into a single value. This value would allow to measure the efficiency of diets. As Farrell and Hart (1998) state, a single aggregated number can be very useful in communicating information on general sustainability to the public and to decision-makers. In engineering, efficiency is defined as the weighted sum of outputs divided by the weighted sum of inputs. Based on this, the eco-nutritional-efficiency (ENE) gives the amount of nutritional value (output) which is provided per produced environmental impact (input). The aggregation of numerous nutritional values and environmental impacts can be carried out in two generic ways (Rüdenauer et al., 2005): weights used during the aggregation can either be determined by expert judgment or based on a specific weighting method. Kuosmanen and Kortelainen (2005) recommended the use of data envelopment analysis (DEA) within the closely related concept of eco-efficiency. The goal of this paper is to examine data envelopment analysis as a method to measure the ENE of diets. Two ENE indexes based on DEA have been proposed. Model 1 is based on the nutritional content, while model 2 includes a nutritional performance measure. A case study comparing 256 daily menus has been used to test the proposedmodels.

2. Methods Geographically, the case study focused on Spanish diets. First of all, the menus for the case study were developed using products with known carbon footprints. In a second step, the nutritional value, based on the macronutrient contents and the recommended daily intake (RDI), was determined. Thirdly, the carbon footprint (CFP) as representative for the environmental impact was assessed based on literature data. In a fourth step this values were aggregated within the ENE using DEA. 2.1. Daily menus

Based on nowadaysfood consumption patterns and CFP availability four daily menus were designed (mediterranean, western, standard and vegetarian). Table 1 shows these four daily menus, each consisting of four meals. On general terms consumers do not follow a strict diet but in their daily menus they mix foods and vary the portions according to personal criteria and preferences. In order to mimic this consumer behavior, 535


combinations of the four meals of each representative menu were made, obtaining 256 daily menus. The daily menus were named according to their meals (breakfast/snack/lunch/dinner); wsvm is therefore a daily menu with a western breakfast, a standard snack, a vegetarian lunch and a mediterranean dinner. After this, all daily menus were normalized to 2000 kcal to enable comparison. 1.2.

Environmental assessment

The CFP of all products was obtained from literature andanalyzed regarding their system boundaries according to PAS 2050 guidelines. When a life cycle stage was not taken into account in a product CFP (e.g., transport to retailer, processing) it was added.To reach a geographical specificity, the modular method for the extrapolation of crop LCA (MEXALCA, Roches et al., 2010) was used. Only sugar from sugarcane and chocolate were assumed to be imported. For all other products, production in Spain was assumed. 1.3.

Nutritional assessment

The nutritional values per edible portion were calculated. The macronutrient content of allmenus was determined using the nutritional database Dietowin v7.3. While in model 1 absolute values are used, in model 2 the recommended daily intake (RDI) fractions of macronutrients were used. According to the FAO-OMS (2003)guidelines, 12-15% of all calories should be delivered by proteins, 30-35% by fat and 50-55% by carbohydrates. The RDIwas used to calculate the nutritional performance using an extent of compliance indicator (ECI) (Equation 1.1). The calculation of the ECI leads to a value of 1 if the macronutrient content is within the RDI range and values below 1 if the macronutrient contents exceed the guidelines or lie below them. i 1  1  actual lbi   ECI   1  actual 1  1  ubi i  

1.4.

if actuali  lbi if lbi  actuali  ubi

(0.1)

if actuali  ubi

Integration of results

The aim of this step was to aggregate the results obtained above within a unique number. The ENE describes the amount of nutritional value gained (macronutrients) by investing a certain amount of environmental impact (CFP). DEA was used to aggregate the multiple system outputs.Specifically, the input-oriented CCR-model was implemented and a constant returns-to-scale was used (Charnes, Cooper and Rhodes, 1978). As DEA is used to assess the relative efficiency of a daily menu within the group of all daily menus taken into account, only the relative position of a daily menu within the group is relevant. For this reason, the analysis of results was performed using the spearman‘s rank correlation coefficient (). Model 1 Equation ¡Error! No se encuentra el origen de la referencia. gives the eco-nutritional-efficiency using model 1 (ENE1), whereiareweights assigned to the outputs andthe weight of the system input.

ENE1 

1  protein  2  fat  3  carbohydrate   carbon footprint

(1.2)

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Model 2 To account for a balanced nutrition, model 2 uses the ECI to calculate the nutritional performance, as given in Equation(0.1). The ECIi for each nutritional valueiis then entered into model 2, given in Equation (1.3).

ENE2 

1  ECI protein  2  ECI fat  3  ECIcarbohydrate   carbon footprint

(1.3)

2. Results 3.1.

Nutritional and environmental assessment

Figures 1and 2 show the results of the nutritional and environmental assessment, respectively. In these figures daily menus are sorted according to their meals. The structure is dominated by the lunch. Secondly, all daily menus having the same lunch were sorted according to their dinner, followed by breakfast and snacks. Regarding macronutrient contents, no extreme outliers or unreasonable menus, which could bias the efficiency frontier, are present. Regarding RDI, only the mediterranean and standard daily menus can be considered healthy. Single meals are often unbalanced:Only 29 daily menus out of 256 follow the health guidelines. As shown in Figure 2, significant differences among the CFP of food were found. Daily menus had a CFP between 2.02 kg CO2-eq (vmvv) and 5.16 kg CO2-eq (wwww). Among the four preliminary modeled menus, the vegetarian one performs the best (2.28 kg CO2-eq). Within the daily menu inspired by western diet, meat and fish consumption leads to the overall worst result of 5.16 kg CO 2-eq. The CFP from meat consumption within the mediterranean and standard daily menu contribute with 34% and 46%, respectively, to the overall result. Vegetal proteins included in the vegetarian daily menu are consumed as pea burger and contribute with 18% to its CFP. Overall, lunch and dinner provide together 62% to 85% of the menus‘ calorific content and provoke 60% to 95% of the CFP. 3.2.

Integration of results

The daily menus analyzed have an ENE between 0.48 and 1 for model 1 and 0.42 and 1 for model 2 (Figure 3). Using model 1, eight daily menus were found to be efficient (mmvs, mwvs, smvs, swvs, mmvv, smvv, vmvv and swvv). It can be seen that all efficient menus include a vegetarian lunch. The macronutrient content of the vegetarian lunch is close to the guidelines and its CFP is 31% to 78% smaller than other lunches. The efficiencies calculated using model 1 correlate with  =-0.89 to the CFP. While model 1bases on the absolute values, model 2 was designed to maximise not only the nutritional content but to optimize the quality of nutrition. Within the RDI-range, meals were rated as nutritionally efficient. The average ENE using model 2 is 0.62 and therewith lower compared to model 1 (0.65). Only a subset of the above found efficient menus were rated as efficient within model 2: mmvv, smvv and vmvv. All of them have a mediterranean snack, and a vegetarian lunch and dinner, only the breakfast varies. Spearman‘s  to the CFP reaches -0.98 and reveals a high dependence on the CFP. As all macronutrient contents are close to the RDI guidelines, the ECI is similar for all menus and the CFP gains on importance. For both models, the correlation to the nutritional values is small for protein and fat and reaches 0.51 as a maximum for carbohydrate.

4. Discussion The investigated daily menus have shown a relative ENE between 0.42 and 1, which means that keeping nutritional values constant, the CFP could be reduced up to 60%. As mentioned above, 15% to 30% of the CFP due to European consumption is related to food. Thus, a reduction of 6% to 12% of the total European CFP seems possible. As DEA is a data based approach, results strongly depend on the input data. In this study, 44 products were used to design the daily menus. A higher variability of CFP and nutritional value could lead to a different efficiency frontier within DEA and influence the ENE. Additionally, the menus were designed to be close to the guidelines, but the actual consumption reveals a different picture. While a maximum of 35% of all calories are supposed to be delivered by fat, in Spain this fraction reaches 42% (Varela Moreiras et al., 2008). While carbohydrates consumption is too low (42%), the protein content meets the RDI. 537


The meat and fish content within a daily menu and its ENE performance correlate strongly. This supports prior studies emphasizing the advantages of vegetarian diets (e.g. Carlsson-Kanyama et al., 2003). This is highlighted by the presence of a vegetarian lunch in all efficient menus. However, to give nutritional guidance regarding protein sources, aspects such as essential amino acids should be assessed. As model1 uses an input-oriented DEA model and absolute nutritional valuesitmaximizes the macronutrient content delivered by the consumption of a certain CFP, irrespective of the menus macronutrient composition and its compliance with the RDI. For this reason, model 1 rates extreme values regarding macronutrient contents positively and can be misleading from a nutritional point of view. But the ENE aims to combine environmental and nutritional performance and, therefore, an unbalanced diet should be rated negatively. For this, model 2 additionally uses the ECI concept, which rates the nutritional performance prior to its aggregation. Nevertheless, only model 1 is applicable where so far no performance measurement could be performed. Model 2 was developed as a first approach to measure the nutritional performance before applying DEA. As the daily menus are designed to be close or within the RDI, their nutritional performance is rated highly. While this is, from a nutritional point of view, preferable, it leads to a high influence of environmental performance on the ENE and the efficiencies calculated with model 2 correlate strongly to the CFP (=−0.98). In addition, the relative weights identified are less balanced between the three macronutrients and often a relative weight of 100% is found for one nutrient (161 relative weights of 100% are identified). As nutritional values are within a narrow range (0.62 -1

0.05). The final product did not differ between treatments: electrical conductivity was ~ 14 dS m , organic material content was 42% and N was 1.84%. 944


In conclusion, biodynamic preparations did not accelerate the composting process or enhance the quality of the compost. The chemical profile of the final compost from the mix of materials used, indicate that, either conventional of biodynamic, the quality was appropriated for its use as soil amendment. Keywords: compost, biodynamic preparations, agro-industrial waste, reuse

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LCA- C&DW: An environmental assessment tool in the waste management of the construction sector Irma Mercante*, María D Bovea, Alejandro P Arena * CEIRS, Facultad de Ingeniería, Universidad Nacional de Cuyo, Mendoza M5502JMA, Argentina

++54 261 4135000 Int. 2142 [email protected]

Abstract Aim. The management of solid wastes has evolved significantly over the past 20 years. Different methodologies have been developed to facilitate the evaluation of management strategies. However, all of them refer to domestic wastes, and include European databases. The aim of this paper is to describe the development of a new computational tool, named LCAC&DW, that allows analyzing the environmental impact of the wastemanagement systems in construction and demolition (C&DW). Methodology. Based on 1t of C&DW as a functional unit, the life cycle of the waste has been divided into stages. These stages include collection, transportation, sorting, recycling and waste disposal. The LCA-C&DWtool considers also the avoided burdens due to recycling. The main variables that characterize the process at each stage have been identified. These sub-models are combined to represent a complete C&DW management system. The inventory data come from both primary sources and literature and specialized databases. The Impact assessment results are summarized in six environmental categories: global warming, acidification, eutrophication, ozone layer depletion, natural resources depletion and photochemical smog. Results. The application of this model allows estimating and analyzing the environmental profile of different C&DW management alternatives. A flexible tool, suitable for adaptation to regional inventory data has been obtained. Conclusions. The LCA-C&DW model provides a tool which support regional and municipal C&DW management planners on the environmental decision making process. Also, it allows to evaluate the last life-cycle stage of buildings or civil infrastructures and to integrate it into their complete life cycle. Key words: life cycle assessment, waste management, construction and demolition waste, computer model, LCA-C&DW

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LCA as a tool of Decision making processfor the Environmental Improvement of wastewater treatment in Latin American and the Caribbean F. Hernández-Padilla*, P. Güereca, A. Noyola. Instituto de Ingeniería – Universidad Nacional Autónoma de México Circuito Escolar s/n, Ciudad Universitaria, México, D.F., C.P. 04510, México.

+52 55 56233600 ext. 1658 [email protected] URL:http://www.iingen.unam.mx

Abstract Purpose. Technology selection of wastewater treatment must take into account not only aspects related to the investment and operating costs, but also the environmental impacts arising from the operation of the wastewater treatment plant (WWTP). For this evaluation, the Life Cycle Assessment (LCA) has proven to be a scientifically robust tool, which supports the process of decision making environmentally responsible. Therefore, the project "Water and Sanitation: LAC Cities Adapting to Climate Change by Making Better Use of Their Available Bioenergy Resources", presents as one of its objectives to identify the environmental impacts of wastewater treatment technologies representative of Latin America and the Caribbean (LAC) through the Life Cycle Assessment and suggest improvement alternatives. This paper presents the results of the LCA, obtained in this project. Methods. The LCA developed in this project determines the environmental impacts of the nine scenarios representative wastewater treatment LAC, which were identified according to the statistical analysis of the information obtained from 2734 WWTP‘s in LAC. Results. The life cycle inventory (LCI) of the 9 scenarios analyzed, considered 26 compounds of wastewater, electricity used, chemicals and transportation. From ICV environmental impacts were evaluated using the methodology CML2001. In this study the scenarios was arranged in three lines: water Line which involvesthetreatmentof water and itsrespectiveuseofelectricity; sludge line which consider thesludge treatmentand disposal and waste line which considerthe transport ofscreeningsand emissionsin a landfillfordisposal. The life cycle assessment indicates that the water treatment line is the one with the biggest environmental impacts in technologies: activated sludge process, trickling filters + UASB and UASB + Activated sludge due to electricity consumption and emissions involving biogas With respect to the sludge line,in the stabilization ponds scenarios, impacts occur primarily in the categories of eutrophication and ecotoxicity due to the metals contentinvolved, in contrast ofactivated sludge scenarios because it is the effluent which has more percentage of metal content. Conclusions. From the evaluation it can be concluded that improvements should be in the control and utilization of landfill gas emissions in the energy efficiency of processes and the use of biosolids to prevent the manufacture of fertilizers. Key words: Life Cycle Assessment, LCA wastewater treatment plants, stabilization ponds technology, activated sludge technology, UASB technology, LCA in Latin America and Caribbean.

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Life Cycle Assessment of Integrated Management of PET bottles generated in the municipality of Ecatepec de Morelos Ulises Emmanuel Jiménez Ocampo1*, Leonor Patricia Güereca Hernández 2, Alfonso Durán Moreno1. 1 Department of Chemistry, National Autonomous University of Mexico, 04510, Mexico DF, Mexico.

Tel. (+52) 55 56233537 2

Institute of Engineering, National Autonomous University of Mexico, 04510, Mexico DF, Mexico.

Tel. (+52) 55 56233600 ext. 8706

Abstract Purpose This study evaluates the environmental impact generated by the Integrated Management of PET bottles (IMPETB) generated in the municipality of Ecatepec de Morelos (EM) and the recycling of them to polyester fiber using the methodology of Life Cycle Assessment (LCA). The objective of this paper is to provide bases for decision making to improve the Integrated Management of Municipal Solid Waste (IMMSW) in EM, due to the fact that the PET bottles represent 8% by weight and 12% by volume of the total Municipal Solid Waste (MSW) generated worldwide, besides being a waste with high added value. EM is a city in the center of México with 1,656,107 inhabitants and a surface of 160.17 km2. Its population has an average level of primary study and a MSW generation per capita of 0.97 kg / hab*day. The EM IMMSW shows various deficiencies, among other factors, the low budget allocated, factors related to regulatory standards, lack of essential infrastructure, and open dumps in public roads, odors, gastrointestinal diseases and injuries for workers, attracting vermin and GHG emissions.

Methods The LCA is developed according to ISO 14040/44. The system is IMPETB comprising the stages of generation, collection, temporal storage, exporting, recycling and final disposal that is currently being developed in EM.The functional unit corresponds to 2.862 tons of PET bottles identified as MSW. The inventory data come from statistics provided by private agencies and from the municipal, state and federal government. The impact categories evaluated with support of SimaPro software are global warming, eutrophication, acidification, human toxicity, ecotoxicity and natural resource depletion.

Results The identification, quantification and characterization of the different environmental impacts associated with each stage of IMPETB are key indicators for the planning and development of alternative solutions for correcting operational, energy, economic, social and environmental inefficiencies.

Conclusions. The implementation of the alternative solutions proposed will improve and optimize the operation 948


of IMMSW and PET bottles minimizing emissions to the environment, health and social affectations of the population, reducing processing costs and infrastructure, earning income by the sale of raw material produced, these contributing to the sustainable development of EM.

Keywords: IMMSW, IMPETB , PET bottles, MSW, recycling of PET bottles

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Improving the Utilization of Garlic Herbaceous Waste in the Diet of Breeding Cows Van den Bosch, Silvia(*)- Savietto, M.- Tacchini, F. - Jordá , R.- Iglesias, G.- Rodríguez, G. *Dto. de Producción Agropecuaria, FCA, UNCuyo. Mendoza. Argentina. Almirante Brown 500. Chacras de Coria. Luján de Cuyo. Mendoza.

Argentina. M5528AHB.++54 261 4135000 int 1231 [email protected]

Abstract The Garlic Herbaceous Waste (CAj) is very appealing for cows, but it offers/adds excessive fiber and it does not exceed the 4.5% of CP (nitrogen 0,8%). This deficit limits the ruminal microbial production and impedes an adeccuate digestion of the fibrous components, limiting the energy contribution. The purpose of the project is to prove if the addition of urea improves the consumption of CAj in young heifers. After the adjusting period, a test was carried out with two batches of three pregnant heifers each crossed with Angus, in separate boxes of the Facultad de Ciencias Agrarias, that were fed only with CAj. Only one was given a supplement with urea on water to 4% (LU), during two weeks and the others were not (LT). The consumption of CAj (Kg.) and water (Kg.) were weighted daily, three times a week corporal condition (scale IPCVA) and classification of manure on a scale ANEMBE with three judges were carried out; and also weekly weight (Kg.). The consumption of CAj per Kg. of metabolic weight (W) of the animal showed averages of 0.057 g.W-1 (LT) y 0.065Kg.W-1 (LU). The LU animals consumed a 14% more CAj, with an average consumption of 60,58 g.d-1 of urea. A rise in the digestibility of the fibers can be attribute to the extra nitrogen for the microbial use, which accelerates the rumial emptying and allows greater intake. When MS consumption is increased so does the consumption of water (LT: 0.160 g.W-1y LU: 0.218 Kg.W-1), LU maintained their weight while the LT lost 13.5 Kg. However, it was not reflected on their corporal condition. The best digestibility was seen in the manure reading: LU presented a mode of 3.3: digestibility between 60- 65%, proteins between 6-10%. LT presented values of 4: proteins between 5 - 7%, digestibility under 56%. The incorporation of urea improved the utilization of CAj in cows.

Key words: waste, garlic, digestibility, NPN

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Life Cycle Assessment of Municipal Solid Waste Management of San Miguel, Buenos Aires, Argentina María Daniela Caprile Área de Ecología – Instituto del Conurbano Universidad Nacional de General Sarmiento Juan María Gutiérrez 1150 CP. 1613, Los Polvorines, Buenos Aires, Argentina

++54 11 4469-7774 [email protected]

Abstract This study is part of my Ph.D. thesis in progress entitled "Life Cycle Assessment of Municipal Solid Waste Management. The case of San Miguel, Buenos Aires, Argentina‖. The main objective is to analyze the environmental impacts associated with the current management of the municipal solid waste (MSW) of San Miguel. The methodological framework is an extended Life Cycle Analysis, where the systemic approach and language system named "Emergy Synthesis" developed by Horward T. Odum is used in order to enrich the study. Mass and energy flows directly involved in the Municipal waste system are identified in order to provide a previous approach that expresses the amount of renewable and non-renewable resources used and the ecosystem services cancellation associated. Is expected to have an overview of the current system state to detect key inputs and outputs of energy and materials that greatly affect their performance, identify areas where environmental improvements can be implemented and propose future scenarios for sustainable municipal solid waste management systems . Keywords: life cycle assessment, municipal solid waste management, emergy assessment, ecosystem services cancellation.

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DOCTORAL WORKSHOP

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Integración de ACV y técnicas de optimización. Caso de estudio: Bioetanol a partir de maíz Resumen El grupo de trabajo posee una vasta experiencia en métodos de optimización y simulación y sus aplicaciones. Sin embargo, la incorporación formal del criterio ambiental en el esquema de optimización no ha sido considerada para la toma de decisiones. Para abordar este aspecto, se ha investigado el estado dearte de técnicas de optimización de procesos y herramientas basadas en la metodología de análisis de ciclo de vida (ACV). Se recopilaron diferentes métodos de evaluación de impacto clasificándolos en función de (a) su origen, (b) su base de modelado, (c) si aplican las dos últimas instancias: normalización y valoración, y (d) cómo las realizan. En este análisis se han encontrado falencias de la metodología: como la no disponibilidad de bases de datos públicas para América Latina, la falta de evaluación de efectos sinérgicos en la etapa de caracterización y una componente subjetiva en varios aspectos, como los límites del sistema, la definición de alcances y objetivos y los métodos de evaluación de impacto escogidos. También se recopilaron diferentes trabajos referidos a la combinación de la metodología ACV y la optimización de procesos publicados en el período 1999-2011, observándose la formulación de problemas multi-criterios como la alternativa más utilizada para la inclusión de los aspectos ambientales. Como en la mayoría de los casos las funciones objetivo económicas se encuentran en conflicto con las ambientales, se ha observado que si bien esta formulación permite hallar la mejor relación de compromiso, el resultado depende fuertemente del criterio de los tomadores de decisiones ya que se hallan un conjunto de soluciones óptimas y no una única solución. A propósito, en la mayor parte de los casos, la función objetivo ambiental utilizada consistió en un único índice generado en la etapa de valoración de los métodos de ACV, cuya aplicación no es recomendada por ISO para estudios públicos. Como caso de estudio se escogió la optimización económica y ambiental del sistema de producción de bioetanol a partir de maíz considerando diferentes zonas del país, con el objetivo de identificar opciones sustentables para la integración de los biocombustibles en el sector del transporte. Se realizaron los ACVs correspondientes a las distintas zonas considerando desde la producción de materia prima hasta la biorefinería y el uso del co-producto (DDGs) como alimento para ganado. Se tuvieron en cuenta dos escenarios principales: sin y con el uso de los residuos del cultivo para los requerimientos energéticos de la planta, manteniendo la cantidad necesaria para la conservación del suelo. En primer lugar se escogió el método de evaluación de impacto Eco-indicator 99 (ya que resultó el más utilizado en el análisis previo), sin embargo, posteriormente se compararon los resultados con el método ReCiPe 2008 debido a que éste último es más completo y permite una normalización mundial además de la europea. La asignación de cargas ambientales entre el producto principal (etanol) y el co-producto (DDGS) se realizó teniendo como referencia el caso de Estados Unidos disponible en la base de datos de ECOINVENT: asignación económica para las etapas comunes y asignación según el balance de carbono para las emisiones 953


de CO2. Si bien la expansión de límites para evitar cualquier tipo de asignación ha resultado de gran interés, un ACV de todos los procesos relacionados al co-producto como sugiere la bibliografía, es decir, la molienda húmeda, el sistema de producción de urea y la molienda de la soja demanda un tiempo superior al disponible en el plan de tesis. En relación al uso indirecto del suelo, si bien no se ha encontrado una metodología estándar para su evaluación, se considera necesario un análisis. Una alternativapodría ser realizar un cálculo de las áreas cultivables disponibles en el país, evaluar los cultivos existentes y analizar distintos escenarios según los cultivos desplazados por el maíz. Las tareas futuras corresponden a relacionar los ACVs realizados con el modelo de optimización con el fin de identificar regiones y tecnologías sustentables y comparar con el combustible fósil equivalente. Para ello será necesario extender los límites del sistema para considerar la distribución del biocombustible y su uso.Para la implementación de ambos métodos de ACV se utiliza el software SimaPro versión Phd, mientras que el software General AlgebraicModellingSystem (GAMS) es usado para resolver los modelos de optimización.

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El Valor Intangible Del Desarrollo Tecnológico: Aspectos Ambientales Florencia Codina, Doctorado en Ingeniería, Facultad de Ingeniería, UNCUYO

Introducción La economía neoclásica-keynesiana considera el ciclo económico como la producción de bienes y servicios por parte de las empresas, que son consumidos por las familias que a su vez ofrecen trabajo, tierra y capital a las empresas, formando un ciclo cerrado. Aquellos elementos que no tienen precio de mercado, como son los materiales de la naturaleza (ej.: energía solar) y los desechos son considerados por fuera del sistema económico (Foladori & Pierri 2005). Una manera que encuentra la economía ambiental neoclásica para incorporar al circuito mercantil estos elementos es mediante la internalización de externalidades. Para ello, es necesario valorizar en términos monetarios tales aspectos ambientales. Sin embargo, para el caso de un desarrollo tecnológico innovador existe una serie de beneficios ambientales y socioeconómicos, difíciles de cuantificar y por ende no valorizados. Todo lo que no está valorizado, por ser ―invaluable‖, pasa a tener valor cero a los fines prácticos. Tanto en el ámbito de ciencia pura, como de aplicación pura o profesión, la valorización está satisfactoriamente resuelta (precio de patentes para el primer caso, y precio de bienes o servicios para el segundo). En cambio, en el ámbito de los desarrollos de tecnologías de aplicación, es decir para el tecnólogo, la valorización de la transferencia no está resuelta. De hecho, las técnicas tradicionales para el análisis económico de la oportunidad de negocio asociado a una nueva tecnología incluyen la consideración de la inversión necesaria, costos operativos e ingresos futuros, pero no incorporan la valorización de los intangibles asociados a la idea tecnológica.

Objetivo Desarrollar métodos y técnicas que permitan, de manera objetiva y auditable, estimar el valor de aspectos intangibles asociados a un desarrollo tecnológico, tomando como caso de estudio el desarrollo de tecnologías de producción de microalgas con fines ambientales y energéticos.

Hipótesis La hipótesis del trabajo sostiene que la cuantificación del valor intangible de una innovación tecnológica aportaría elementos útiles para la toma de decisiones en proyectos tecnológicos.

Identificación de variables El primer paso para la cuantificación del valor intangible del desarrollo tecnológico, en este caso la producción de microalgas con fines ambientales y energéticos, es identificar aquellas variables que lo componen.Tales variables pueden agruparse según su naturaleza en variables ambientales y variables socioeconómicas. Para esta presentación (CILCA 2013, Doctoral Workshop) se acotará el análisis a las variables ambientales. 

Variables ambientales: Estas variables reflejan los beneficios para el medio ambiente que se obtendrían al aplicar la tecnología desarrollada. Pueden cuantificarse con herramientas desarrolladas, como el Análisis de Ciclo de Vida (ACV), de una manera objetiva. La ventaja de aplicar la metodología de ACV es que se consideran también los impactos negativos del ciclo completo de producción (ej.: Uso de fertilizantes, consumos energéticos durante la cosecha y extracción de aceites, 955


etc.) que podrían contrarrestar los beneficios de la actividad, por lo tanto se reflejan los impactos netos. Las variables ambientales para el desarrollo de cultivos de microalgas pueden ser(Chisti 2007; Sheehan et al. 1998; J. R. Benemann 1997; Campbell et al. 2009; Stepan et al. 2002; O‘Connor 2011): o

Captura de CO2: La capacidad de mitigación de CO2 del sistema, y su contribución a disminuir el efecto invernadero, puede cuantificarse y expresarse en kg CO 2 eq, acorde a la metodología de ACV.

o

Tratamiento de efluentes: La capacidad depuradora de las microalgas puede aprovecharse para remover fósforo y nitrógeno de efluentes urbanos pre-tratados, u otro tipo de efluente industrial. Puede medirse aplicando las técnicas de ACV para categorías de impacto tales como Eutrofización.

o

Fuente renovable de energía: La generación de una fuente renovable de energía (con energía solar primaria) contribuye a disminuir la demanda de combustibles fósiles y por ende el detrimento de recursos no renovables, como es el petróleo. Puede medirse aplicando las técnicas de ACV para categorías de impacto como Energías renovables y no renovables.

o

Reutilización de agua de cultivo: Una particularidad del cultivo de microalgas en comparación con los cultivos terrestres tradicionales es la posibilidad de reutilizar el agua de cultivo, una vez efectuada la cosecha. Esto disminuye notablemente los requerimientos de agua y resulta vital para la producción de cultivos energéticos en zonas desérticas. Podría medirse comparando la cantidad de agua necesaria para la producción de microalgas respecto al requerimiento de agua para la producción de otro cultivo, por ejemplo soja, tomando como unidad de comparación los kg de biomasa, los MJ producidos, o por hectárea.

o

Ecosistema y biodiversidad: La mayoría de los proyectos de investigación de cultivo de microalgas centran sus estudios en aislar especies que optimizan la producción de aceites o maximizan la productividad de biomasa. Así, una tecnología que utiliza consorcios de microalgas autóctonas, además de tener ventajas operativas como la ausencia de condiciones de esterilización, presenta menor riesgo de contaminación de ecosistemas con especies foráneas, y por lo tanto un equilibrio más estable con el ambiente donde se emplace el sistema.

o

Sinergia entre variables: El hecho de poder combinar en un mismo proyecto aspectos diversos como mitigación de CO2, tratamiento de efluentes y producción de energías renovables implica un beneficio extra. Es decir, el valor de un proyecto que reúne todos estos beneficios debería ser mayor que la suma de tales beneficios por separado.

Metodología Se propone realizar un análisis por escenarios, planteando al menos dos escenarios: uno actual, sin la aplicación de la tecnología, y otro con un porcentaje de implementación de la tecnología a gran escala (ej.: 10% de biocombustible de algas sobre el total nacional de producción de combustibles líquidos). Se utilizará la técnica de ACV para cuantificación de variables ambientales en cada escenario.

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Datos El presente trabajo se enmarca en el Proyecto algae-oil: Producción de microalgas para extracción de aceite y obtención de biocombustibles, UNCUYO. Para la realización de este trabajo se utilizarán datos obtenidos de experiencias de laboratorio y piloto pequeño, extrapolaciones a escalas comerciales y también datos de bibliografías.

Resultados esperados Con los resultados del análisis, se espera estimar cuantitativamente las diferencias entre aplicar o no una tecnología innovadora, en este caso haciendo foco en los aspectos ambientales de la producción de microalgas para biocombustibles y fines ambientales. La cuantificación objetiva de estas diferencias aportará elementos para establecer, en estudios posteriores, el valor económico de los intangibles asociados al desarrollo tecnológico. La cuantificación de estos aspectos intangibles puede ser una herramienta fuerte a la hora de negociar el financiamiento de proyectos de desarrollo tecnológico y para la atracción de inversores de riesgo.

Bibliografía Benemann, J.R., 1997. CO2 mitigation with microalgae systems.Energy Conversion and Management, 38, pp.S457–S479. Campbell, P.K. et al., 2009. Greenhouse Gas Sequestration by Algae: Energy and Greenhouse Gas Life Cycle Studies, CSIRO Energy Transformed Flagship. Chisti, Y., 2007. Biodiesel from microalgae.Biotechnology Advances, 25(3), pp.294–306. Foladori, G. & Pierri, N., 2005.Sustentabilidad? : desacuerdos sobre el desarrollo sustentable, México, D.F.: Cámara de Diputados, LIX Legislatura, Estados Unidos Mexicanos : Universidad Autónoma de Zacatecas :

M.A.

Porrúa.

Available

at:

http://estudiosdeldesarrollo.net/pagina_tipo_cuatro.php?libro=sustentabilidad. O‘Connor, D., 2011. Algae as a feedstock for biofuels. An assessment of the current status and potential for algal biofuels production, IEA Bioenergy Task 39 & IEA Advanced Motor Fuels Implementing Agreement. Available at: http://www.globalbioenergy.org/uploads/media/1008_IEA_Bioenergy__Current_status_and_potential_for_algal_biofuels_production.pdf [Accessed February 8, 2013]. Sheehan, J. et al., 1998. A look back at the US Department of Energy‘s Aquatic Species Program: Biodiesel from algae, National Renewable Energy Laboratory. Stepan, D.J. et al., 2002. Carbon dioxide sequestering using microalgal systems US Department of Energy Report., 2002-EERC-02-03.

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Análisis de Ciclo de Vida de la Gestión de los Residuos Sólidos Urbanos de San Miguel, Buenos Aires, Argentina Introducción Estado de arte y definición del problema La gestión de los residuos sólidos urbanos (RSU) en el Área Metropolitana de Buenos Aires (AMBA) constituye una preocupación prioritaria para los gobiernos municipales y provincial. En la actualidad el mayor problema se centra en la falta de disponibilidad de espacios para la disposición final de los RSU, ya que el único relleno sanitario que opera en la región es el ubicado en el Complejo Ambiental Norte III de CEAMSE (Coordinación Ecológica Área Metropolitana del Estado). Tal relleno no solo genera un impacto ambiental para las poblaciones cercanas, sino que su vida útil es acotada a abril de 2013 y existen claras dificultades para las gestiones locales de encontrar alternativas para la localización de nuevos rellenos sanitarios. A esto se suma la falta de programas de Gestión Integral de Residuos de escala en la región (solo hay experiencias piloto en algunos municipios), que tiendan a minimizar los residuos que deben ser dispuestos en rellenos sanitarios; y una conciencia ambiental poco desarrollada en la comunidad en general respecto a la importancia de implementar estrategias de separación en origen y minimización de la generación de residuos. Se presenta así una situación crítica donde la cantidad de RSU generados crece mientras la disponibilidad de sitios de disposición final aceptables desde el punto de vista ambiental, político, económico y social se reducen. Esta realidad pone en evidencia la importancia de contar con estudios que aborden dicha problemática de manera integral. El presente trabajo se focalizará en la evaluación del actual Sistema de Gestión de Residuos Sólidos Urbanos del Partido de San Miguel. Se aplicará un Análisis de Ciclo de Vida Extendido (ACV) con el objetivo de identificar, cuantificar y caracterizar los diferentes impactos ambientales potenciales, asociados a cada una de las etapas de la gestión de los residuos sólidos urbanos; y se analizará y comparará diferentes alternativas de gestión de residuos, resaltando aquéllas que se focalicen por un lado, en minimizar la cantidad final de residuos depositados en rellenos sanitarios y la polución asociada a su tratamiento y recolección; y por el otro, en maximizar la recuperación de energía y materiales.

Objetivo del Estudio e Hipótesis de trabajo Hipótesis de trabajo: La Emergía y la Entropía pueden convertirse en nuevos Indicadores de Impacto Ambiental que complementen el Análisis de Ciclo de Vida de la Gestión de los Residuos Sólidos Urbanos.

Objetivo General Evaluar el impacto ambiental del actual sistema de gestión de residuos sólidos urbanos del Partido de San 958


Miguel y proponer un sistema integral de gestión de los residuos sólidos urbanos basado en el Análisis de Ciclo de Vida.

Preguntas de investigación 1. ¿Es compatible el crecimiento económico con las metas de cuidado del medio ambiente o estamos acaso frente a una paradoja? 2. ¿Qué metodología de valoración podríamos utilizar para dar cuenta de los límites biogeofísicos de la naturaleza?. 3. ¿Pueden la Emergía y la Entropía convertirse en nuevos Indicadores de Impacto Ambiental del Análisis de Ciclo de Vida de la gestión de los residuos sólidos urbanos?

Metodología La metodología a aplicar para la evaluación de los impactos ambientales será un Análisis de Ciclo de Vida extendido, porque se incorporará al ACV el Análisis Emergético y el Análisis Entrópico, no contemplados en los ACV convencionales.

Contribuciones y Resultados esperados La integración de la Emergía y de la Entropía al Análisis de Ciclo de Vida, podría ofrecer un cambio de paradigma, al proporcionar una perspectiva de análisis más amplia que la antropocéntrica, orientada hacia una nueva forma de valoración; una valoración con base termodinámica, que de cuenta de los límites biogeofísicos de la naturaleza y que valore el trabajo realizado por ella. Se espera que los resultados derivados de dicho análisis permitan obtener una visión holística del sistema bajo estudio donde se detecten aquéllas entradas y salidas clave de energía y materiales que afectan en mayor medida el rendimiento del sistema. De manera tal que sirvan de base para la toma de decisiones basadas en datos científicos y que posibiliten la implementación de sistemas sustentables de gestión de los residuos sólidos urbanos. Por otra parte la revisión bibliográfica realizada da cuenta de la inexistencia en nuestro país de trabajos de investigación que aborden la problemática de los residuos sólidos urbanos desde la óptica aquí planteada. En ese sentido existe un campo de investigación a explorar, al que la presente investigación pretende contribuir, de manera de aportar al enriquecimiento de las investigaciones actuales.

Recursos

disponibles

(información,

equipamiento,

soporte institucional) Becaria Doctoral. Proyecto PRH Nº 9 UNGS Programa Recursos Humanos de la ANPCyT Componente: Proyecto de Formación de Doctores en Áreas Tecnológicas Prioritarias (PFDT) Línea: residuos.

Lugar de Trabajo: UNGS (Universidad Nacional de General Sarmiento) ICO (Instituto del Conurbano) Área de Ecología

959


Análisis del Ciclo de Vida del Manejo Integral de las botellas de PET que se generan en el Municipio de Ecatepec de Morelos Ulises Jiménez Ocampo1* 1 Facultad de Química, Universidad Nacional Autónoma de México,04510, México D.F,, México.

Tel. (+52) 55 56233537

Objetivo El presente estudio evalúa el impacto ambiental generado por el Manejo Integral de las botellas de PET y su Reciclaje a fibra de poliéster que se generan en el municipio de Ecatepec de Morelos (EM), utilizando la metodología de Análisis de Ciclo de Vida (ACV). El objetivo del trabajo es ofrecer fundamentos para la toma de decisiones para la mejora del Manejo Integral de los Residuos Sólidos Urbanos y el Reciclaje de las botellas en EM, lo anterior considerando que las botellas de PET representan el 8% en peso y 12% en volumen de los Residuos Sólidos Urbanos, además de ser un residuo con gran valor agregado. EMes un municipio del centro del país con 1,656,107 habitantes y una superficie de 160.17 km2. Su población tiene un nivel de estudio promedio de educación primaria y una generación per cápita de RSU de 0.97kg /hab día. El Manejo Integral de los Residuos Sólidos Urbanos en EM presenta diversas ineficiencias debido, entre otros factores, al bajo presupuesto que se asigna, factores relacionados a incumplimientos normativos e intereses.Existe carencia de infraestructuraindispensable,tiraderos a cielo abierto y en la vía pública, malos olores, enfermedades gastrointestinales y lesiones en los trabajadores,atracción de fauna nociva y emisión de GEI.

Metodología El ACVse desarrolla acorde a las normas ISO 14040/44. El sistema es el Manejo Integral de las botellas de PET que integran las etapas de generación, separación, recolección, transporte, reciclaje y disposición finalque se desarrolla actualmente en EM. La unidad funcional son 2,862 toneladas de botellas que fueron recolectadas durante el año 2011.Los datos para el inventario provienen de estadísticas e informespresentados por organismos públicos y privados de carácter municipal, estatal y federal. Las categorías de impacto evaluadas son el calentamiento global, eutrofización, acidificación, toxicidad humana, ecotoxicidad y agotamiento de recursos naturales.

Resultados La identificación, cuantificación y caracterizaciónde los diferentes impactos ambientales asociados a cada una de las etapas del Manejo Integral de las botellas de PET son indicadores primordiales para el planteamiento y desarrollo de alternativas de solución para la corrección de las ineficienciasoperacionales, técnicas, económicas, sociales y ambientales presentes en el actual Manejo de los Residuos Sólidos Urbanos en EM.

Conclusiones Con la implementación de las alternativas de solución propuestas, el Manejo de los Residuos Sólidos Urbanos y el Reciclaje de las botellas se mejorará y optimizará su operación minimizando las emisiones al ambiente, afectaciones sociales y de salud de la población, reducción de costos de proceso e infraestructura, obteniendo ingresos por la venta de los RSU valorizables y coadyuvando así aldesarrollo sustentable de EM. 960


Palabras clave: MIRSU, RSU, botellas de PET, RBPET

961


Technological Parametrized Lifecycle Analysis Method For Wall Insulation

Introduction: the problem to be studied The Productive Chain of the Construction Industry (PCCI) is one of the most important areas of the economy, in economic, social and environmental aspects. Its GDP amounts to 5.35% of the national GDP, and it is fundamental in eliminating the housing deficit in Brazil, which represents a gat of 23.49 million homes until 2022. Considering environmental aspects, the PCCI demands high volumes of raw material, energy and water, and produces 40% of the solid residues (SINSUCON-SP, 2011; CBIC, 2011; ATHENA, 2000). Considering this context, there is a demand for evaluating the environmental performance of Construction products and processes, since they are widely used. The field of Industrial Ecology seeks to understand the ecological mathematics involved in the calculation of potential impacts from the productive processes adopted and applies the Lifecycle Analysis method for this. The product, material, process or service is evaluated in all stages of its lifecycle. The application of LCA methods in the PCCI can contribute to the design of more sustainable buildings, allowing for an evaluation of the environmental performance of materials and products, as well as raising awareness to the benefits of sustainable construction practices (GOLEMAN, 2009; VIGON et al, 1995; KEELER et al, 2010). In Brazil, there are challenges in the application of LCA methods in the construction context, mainly because of the complexity of this supply chain, characteristics of the final products, and the lack of a national database. Regardless, Brazil is starting to build a LCA system, via de Brazilian Program for Lifecycle Analysis (PBACV in Portuguese). We thus observe initiatives for promotion of LCA methods in spite of the challenges and bottlenecks against its implementation. Among the challenges, we can highlight the need of developing Parameterized Technological Models (PTM) for applying LCA methods specific to construction products. The development of these PTM will define a scheme of methodological steps to be considered in the environmental evaluation of these products, considering their lifecycle, facilitating the flow of information in the LCA application processes and the operability in standardizing these studies. In developing the Masters‘ degree dissertation the bloc of compacted cement-soil mix was adopted as a case study object for developing the PTM, as well as identifying the state of the art of LCA methods applied to the construction industry. In the development of the Doctorate thesis, the scope was expanded to include the supply chain of products used in wall insulation sub-systems, to validate the applicability of the PTM. The flexibility of the model will be evaluated as well, taking into account the limitations established by the complexity and variability of the productive processes and raw materials in the PCCI.

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Goals General objective: to test a Parameterized Technological Model for construction products used in the wall insulation sub-system. Specific goals: 

To carry out a bibliography review of main concepts;



To evaluate the state of the art of LCA application in the construction industry in the public, private and academic sectors;



To test the applicability of the Parameterized Technological Model for construction products.

Hypothesis The development of the Parameterized Technological Model for application of LCA methodology is applicable to the construction products used in the wall insulation sub-system, in the Brazilian context.

Methodology The following methodological steps will be adopted: (a) A review of the bibliography covering the main concepts in the areas of PCCI, Industrial Ecology, LCA and Wall Insulation; (b) Classification of the types of wall insulation according to function, components and materials used; (c) Evaluation of the state of the art of LCA application in the PCCI in Brazil and the world, with evaluation of academic publications, private sector initiatives and public policies which involve LCA methods. (d) Characterization of the supply chains of concrete models 53 defined and data gathering; (e) Definition of a model-object built based on the concrete models characterization; (f) Definition of PTM variables; (g) Creation of PTM for LCA application according to the model-object, the variables, the NBR ISO 14.040 and 14.044 standards and the International Reference Life Cycle Data System Handbook (ILCD); (h) Applicability test for the developed PTM based on the case study of a type of wall insulation to be defined, as well as the data gathering and analysis of environmental impacts associated with the supply chain. Inputs and outputs will be analyzed and related to defined indicators of environmental impact, and the process which can be optimized will be identified; (i) Validation of the PTM.

53

The characterization of the Cement Soil Blocs was already conducted for the Master’s degree dissertation. 963


Chronogram Main activity

Semesters 1

2

3

Carried 4

5

6

7

8

9

Out

Bilbiography Review

Yes

Definition of classification of wall insulation

Partial

Chapter 1 Creation

Partial

Evaluation of State of the Art of LCA in PCCI

Yes

Chapter 2 Creation

Yes

Criteria for definition of products to be characterized

No

Concrete Model 1: data gathering for characterization of the

Yes

Soil Cement Bloc Supply Chain Concrete Model 2: data gathering for characterization of the

No

Case 2 Supply Chain Chapter 3 Creation

Partial

Definition of Model Object and PTM variables

No

PTM development

No

Project qualification

No

PTM viability test

No

LCA methodology application

No

Chapter 4 creation

No

Conclusion creation

No

Obtained and expected results and contributions Among the obtained results are: creation of a classification system for the wall insulation sub-system based on function, components and materials used; evaluation of the state of the art of LCA in Brazil and the world in the academic, private and public sectors; evaluation of data and characterization of the Soil Cement Bloc productive chain; and partial development of the PTM based on the Soil Cement Bloc case study. The expected results are: creation of a flowchart of questions to gather data on the supply chains, which can be used for other supply chains; characterization and evaluation of data from other supply chain of wall insulation sub-system products; development and test of applicability of PTM; and LCA study for a product of Wall insulation sub-system. This research seeks to develop a technological tool which is fundamentally important to the definition of a basic structure to subsidize the evaluation of environmental performances of PCCI products along their lifecycles.

964


Necessary Resources GaBi software licenses for the development of PTM analyzes, as well as a specific database for construction. Visits to the makers and suppliers of studied concrete-models.

Bibliography Athena (2000) Building as Products: Issues and Challenges for LCA. International Conference on Life Cycle Assessment: Tools for Sustainability. Arlington, Virginia. CBIC (2011) Desenvolvimento com Sustentabilidade: Construção Sustentável. http://www.cbic.org.br/sites/ default/files/Programa-Construcao-Sustentavel.pdf. Accessed 28 September 2011. Goleman, D (2009) Inteligência Ecológica: O impacto do que consumimos e as mudanças que podem melhorar o planeta. Tradução de Ana Beatriz Rodrigues. Rio de Janeiro: Elsevier. Keeler, M.; Burke, B (2010) Fundamentos de projetos de Edificações Sustentáveis. Porto Alegre: Bookman. Sinduscon-SP (2011) Construção Civil: Desempenho em 2011 e perspectivas para 2012.

http://www.

sindusconsp.com.br/downloads/imprensa/2011/ coletiva.pdf. AAccessed 14 June 2012. Vigon, B. W. et al (1995) Life Cycle Assessment: Inventory Guidelines and Principles. Cincinnati: U. S. Government Printing Office.

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Energía y Huella de Carbono de Edificios Habitacionales en México: Escenarios de Mitigación Ante el Cambio Climático Ricardo Ochoa Sosa Universidad Nacional Autónoma de México, Instituto de Ingeniería Doctorado en Energía en Diseño Bioclimático de Edificaciones (Segundo semestre)

Introducción Las distintas principales etapas del ciclo de vida de las edificaciones son: la extracción y manufactura de materiales, el transporte de los mismos, la construcción, el uso y la demolición. Todas las etapas tienen impactos ambientales relacionados, pero en especial la etapa de uso tiene importantes impactos relacionados al uso de energía para climatización.

El diseño bioclimático considera el clima, las propiedades físicas de un edificio y los aspectos psicométricos relacionados al confort, para optimizar el uso de recursos y energía en el ambiente construido. Durante la etapa de diseño de una edificación se plantea qué propiedades físicas debería tener la envolvente para satisfacer los niveles de confort de los usuarios. En esta etapa el clima es definido a partir de las normales climatológicas; es decir, a través de los valores medios de las variables meteorológicas (temperatura, humedad, precipitación, viento, etc.) de los últimos 30 años.

El clima ha tenido alteraciones de manera natural durante la historia de la tierra. Sin embargo, en las últimas décadas se han registrado cambios que pueden atribuirse a actividades humanas. Estas variaciones en el clima – a diferencia de las naturales–, se han dado de manera acelerada y han repercutido tanto en el medio natural (arrecifes, manglares, selvas, bosques, glaciares, etc.), como en el ambiente construido. Aunque el orden de magnitud de las variaciones en la temperatura superficial de la tierra corresponde a décimas de grado, se ha estimado que podría llegar a ser de hasta 6.4 C.

Definición del problema Lo descrito en párrafos anteriores implica que un edificio, diseñado para hacer un uso óptimo de energía y de recursos mediante la incorporación de técnicas de diseño bioclimático, podría tener un desempeño ambiental y económico completamente distinto en las próximas décadas si se diera una alteración en el clima. Es decir, el diseño óptimo para el clima actual no es necesariamente un diseño óptimo para el futuro, si se consideran los escenarios de cambio climático. Esto se puede demostrar mediante el modelado y la simulación del desempeño energético de edificaciones en función las variables climatológicas –normales climatológicas y proyecciones de cambio climático.

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Estado del arte Diversas investigaciones han demostrado que ante una alteración en el clima, la demanda en el uso de energía de los edificios se vería alterada. En éstas investigaciones se han considerado distintos escenarios de cambio climático, regiones, tipos de edificios y se han evaluado también niveles de incertidumbre en los cálculos. Sin embargo, los impactos han sido analizados únicamente para la etapa de uso de las edificaciones. Adicionalmente, la mayoría de los estudios se han enfocado en simular el comportamiento de las edificaciones en zonas predominantemente frías y solamente algunos han analizado regiones tropicales.

Principales preguntas Esta investigación toma como estudio de caso las edificaciones habitacionales y analiza su comportamiento ambiental y económico bajo distintas perspectivas de cambio climático. Con este análisis se pretende entender si la demanda de energía de las edificaciones habitacionales en México se vería alterada ante el cambio climático; y de ser así qué oportunidades existen para reducir la demanda de energía mediante la incorporación de técnicas de diseño bioclimático en las edificaciones.

Objetivo El objetivo general de esta investigación es proponer escenarios de mitigación y de un uso más eficiente de los recursos ante escenarios de cambio climático, mediante el diseño bioclimático en edificaciones habitacionales.

Hipótesis Las hipótesis para este estudio son: (1) Existe una relación estrecha entre clima y consumo energético en edificaciones. Si el clima cambia, también cambiará el consumo energético del edificio, así como su huella de carbono. (2) El análisis de costos de los edificios bajo distintos escenarios provee información útil para la toma de decisiones en materia de edificación y diseño bioclimático, que no es posible determinar a partir de un único escenario de clima.

Metodología Se realiza una serie de estudios de caso de edificaciones habitacionales en México, y se evalúan: a) el desempeño energético, mediante la estimación de la demanda acumulada de energía,

b) los impactos

ambientales, mediante el cálculo de la huella de carbono y c) el desempeño económico, mediante un análisis de costos nivelados; bajo distintos escenarios de cambio climático. Se lleva a cabo un análisis de sensibilidad ante la implementación de distintas técnicas de diseño bioclimático y se realiza un análisis de incertidumbre para todas las variables involucradas en los cálculos.

Resultados esperados Se obtendrán una serie de escenarios en los que se evalúe la demanda acumulada de energía, la huella de carbono y los costos nivelados de edificios habitacionales en México, para presentar propuestas de diseño bioclimático para mitigación y adaptación ante el cambio climático. 967


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Envolventes De Hormigon Liviano Sustentable: Diseño Y Propiedades Para El Ahorro Energetico Iris, Sánchez Soloaga. Becaria Doctoral CONICET. CINTEMAC. UTN. Facultad Regional Córdoba.

Es conocido el problema energético que afecta al planeta y su vinculación con el concepto de sustentabilidad; por ello la utilización de materiales ecológicos se presenta como una alternativa importante y muy valorada en cualquier obra de ingeniería. Una construcción sustentable o los llamados ―edificios verdes‖ son cada vez más requeridos en el mercado y sin duda que los materialesy el diseño son una parte importante para hacer que una vivienda pueda ahorrar energía por sí sola. En este sentido el hormigón no ha querido quedarse atrás. En el marco conceptual de las envolventes de hormigón liviano sustentable, motivo de esta tesis, se agrega una variable a considerar que es la transmitancia térmica (K). Existe una amplia gama de soluciones que permiten mejorar las características térmicas de una vivienda, desde aquellas más conocidas que consisten en colocar capas de material aislante en el interior o exterior de los muros, hasta soluciones más novedosas como la incorporación de aislante en el centro de un muro de hormigón, el uso de hormigón celular y los moldes de poliestireno expandido. Sin embargo todos los ejemplos nombrados con anterioridad, no presentan un único material que reúna las propiedades de aislación térmica, sino un sistema constructivo conformado por varios materiales de diferentes características. Esto lleva a un mayor costo en la ejecución de los paneles, con la necesidad de incorporar varios materiales y debiendo tener especial cuidado en las uniones para evitar los puentes térmicos. A nivel nacional, existen muy pocos antecedentes de investigaciones realizadas sobre materiales que reúnen propiedades aislantes y de soporte estructural. Puede citarse: El CECOVI, UTN. Facultad Regional Santa Fe, elaboró un material de construcción constituido por un mortero alveolar obtenido a partir de cemento, arena, agua y agente espumígeno. La transmisión de calor a través de este hormigón, es muy reducida debido a la presencia de multitud de pequeñas y finísimas retículas de cemento fraguado que contienen aire encerrado en burbujas con un volumen lo suficientemente pequeño como para que no se produzca transmisión de calor por convección. Otra experiencia a nivel nacional fue realizada por el CINTEMAC, UTN. Facultad Regional Córdoba, quienes han realizado un estudio para mejorar la aislación térmica de los hormigones con la utilización de residuos sólidos no biodegradables (polietileno y polipropileno) utilizado como agregado liviano. A nivel internacional, (Miller, 2007), ha ideado una manera de reutilizar los residuos plásticos como agregado en el hormigón, contribuyendo a mejorar sus propiedades aislantes. Al moler plástico y su mezclado con cemento portland, Miller fue capaz de crear un material tan resistente como el hormigón convencional. Por otra parte, los investigadores del Centro Tecnológico de Letonia y del Instituto de Mecánica de Polímeros de la Universidad de Letonia, en colaboración con Hormigones Uniland, empresa cementera española, han logrado convertir residuos poliméricos termoplásticos en una sustancia aglutinante que podría mezclarse con otros materiales, como la arena, y dar lugar a un hormigón polimérico sin cemento. Realizaron ladrillos de hormigón polimérico, (Balodis, 2008) que tienen el mismo aspecto que los ladrillos comunes de cemento, absorben menos agua, por lo que resiste muy bien las variaciones de temperaturas y las heladas. Puede usarse en exteriores y para pavimentación urbana. Sin embargo, los ladrillos no se pueden utilizar en edificios porque 969


el hormigón polímero no cumple con las normas de regulación de fuego del material. Por otra parte el crecimiento de la industria del plástico mundial ha sido enorme llegando a 100 millones de toneladas en 2001 (www.wasteonline.org.uk). Los residuos plásticos industriales y domésticos constituyen entonces una creciente amenaza para el medio ambiente y su destino final merece un esfuerzo para su desarrollo. En la ciudad de Córdoba es factible la obtención de reciclado de plásticos que, mediante su concentración selectiva, pueda ser reutilizado incorporándolo al hormigón, como parte de agregados gruesos, disminuyendo la utilización de materias primas naturales, minimizando el volumen de acopio de los residuos y los riesgos de contaminación consecuentes, obteniendo además un material con propiedades térmicas que contribuya al ahorro energético. El objetivo principal de esta tesis doctoral es evaluar las propiedades mecánicas y térmicas de los hormigones livianos sustentables con agregados procedentes de residuos plásticos, desarrollando criterios para su diseño y aplicación, contribuyendo así a optimizar las envolventes constructivas. Para ello se propone:  Desarrollar dosificaciones para hormigones livianos sustentables que incorporen agregados procedentes de residuos plásticos.  Caracterizar física, mecánica y térmicamente las mezclas de hormigones livianos sustentables con residuos plásticos, incluyendo criterios de durabilidad.  Proyectar con este nuevo material un elemento constructivo que a partir de su mismo diseño formal y como parte de un sistema estructural contribuya a mantener el confort térmico.  Verificar el ahorro energético a partir del estudio de las propiedades de estos hormigones y su aplicación en un elemento constructivo, contribuyendo a un ahorro energético respecto de la construcción tradicional. En los ensayos de asentamiento realizados hasta el momento se pudo observar una consistencia seca y cohesiva en lasmezclas que incorporan plásticos. En estado endurecido, la resistencia a compresión obtenida en los hormigones con CPC40 y plástico bicapa de silobolsa fue relativamente baja en comparación con los resultados obtenidos en el hormigón patrón, sin plástico, HPC0. Analizando estos resultados se decidió cambiar el CPC40 por un CPN40 buscando un aumento de la resistencia a compresión y justificando también este cambio por ser el CPN40 más utilizado en la industria de la prefabricación. Los resultados indican que los hormigones que mejor respuesta han tenido son los del grupo CPN40. Con el 10% y 20% de reemplazo del agregado grueso por plástico multicapa (mezcla de PVC, PP y OPP), se alcanzaron resistencias a compresión que, si bien son menores que el de referencia HPN0, son buenos en comparación con el hormigón patrón.En la caracterización térmica de estos hormigones los resultados del ensayo de conductividad mostraron una disminución en la transmitancia térmica con el agregado del plástico multicapa. Como conclusión los resultados obtenidos permiten estimar que los agregados provenientes de residuos plásticos multicapa son adecuados para su uso en la industria de la construcción disminuyendo la conductividad térmica del hormigón y logrando resistencias mecánicas adecuadas.Se continuará con el plan experimental propuesto estudiando la incorporación del plástico multicapa al hormigón, su dosificación, características mecánicas y de durabilidad y especialmente sus propiedades de conductividad térmica, a los fines de verificar su capacidad aislante.

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PLENARY CONFERENCE

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La Comunicación Estratégica del Pensamiento de Ciclo de Vida desde la perspectiva regional y mundial Ana Quirós*, Sonia Valdivia, Thad Mermer *ECO GLOBAL y ALCALA, P.O.Box 134, 1000 San José Costa Rica

+506 22894106, +506 89190937 [email protected] URL:http//:www.ecoglobal.com y http//:www.alcalacr.org

Introduccion Reconociendo la importancia de difundir el pensamiento de ciclo de vida (PCV) y la necesidad de desarrollar capacidades en la región en relación con la Evaluación de Ciclo de Vida (ECV), tanto la Red Ibero Americana para Ciclo de Vida (RIBCV) como la Iniciativa Internacional de Ciclo de Vida UNEP/SETAC (IILC)han desarrollado e implementado instrumentos de comunicación bajo el marco de una visión estratégica.

El Proposito Presentar a los participantes la estrategia de comunicación que actualmente desarrolla, y está en el proceso de implementación, la IILC (Fase 3: período 2012-2017) a nivel global y en específico relativo a la acción conjunta y de apoyo con la gestión de comunicación que mantiene la RIBCV en la región. Además, el proceso de comunicación es dinámico y cambiante por lo que se eleva a discusión posterior la estrategia, en particular los indicadores de desempeño identificados.

El Método Se proporciona breve reseña sobre el desarrollo de IILC y de los antecedentes de la RIBCV. Se presentan los principales objetivos Fase 3 de IILC y la forma en que la estrategia de comunicación es elaborada: estudios base, encuestas y definición de elementos: selección de audiencias meta, mensajes clave, instrumentos idóneos e indicadores de desempeño. Se brinda ilustración del caso CILCA en la región. Se plantea la importancia de aportar opinión sobre la estrategia y sus elementos, en particular sobre los indicadores.

Los Resultados En específico, se reporta que: 1. la audiencia meta de la Fase 1 y Fase 2 es los profesionales de ECV, reafirmando la correspondencia entre los elementos de comunicación y los objetivos de estas fases de la IICV -se ejemplifica el resultado con logros, 2.

es posible expresar los objetivos de la Fase 3 en términos de comunicación -ilustrando con cuadro de correspondencia;

3.

se definen recomendaciones para concretar la implementación considerando sub-categorías de audiencias, categorías para los mensajes clave y variedad de instrumentos,

4.

es oportuno aplicar nuevos instrumentos e innovar,

5.

conviene utilizar indicadores de desempeño,

6.

se deben asegurar recursos para mantener la comunicación. 972


Conclusiones El desarrollo de una estrategia de comunicación relacionada con la difusión del PCV, desarrollo de capacidades y transferencia de información que oriente a mejores decisiones sobre consumo, producción y estilos de vida sustentables es un proceso complejo pero indispensable. Requiere entre otros de estudios base, actualización constante y recursos adecuados.

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Global LCI for primary copper Gustavo Lagos C.C.* *Universidad Católica de Chile, Vicuña Mackenna 4860, Macul, 7820436, Santiago, Chile, ++56223545895,

[email protected] www.gustavolagos.cl

Resumen El propósito de este trabajo es analizar los principales resultados del Inventario Global de Ciclo de Vida (LCI) concluido en 2011 para el cobre primario y comparar sus resultados con los valores que se citan en la literatura académica. Este estudio, con una muestra del 30% de la producción mundial en 2007 proveniente de yacimientos de seis compañías mineras en cinco continentes, cuantifica los recursos y la energía utilizados,así como las emisiones generadas en los procesos productivos desde la mina hasta los concentrados y cátodos. Incluye los procesos hidro y pirometalúrgicos, entregando resultados de un mix que corresponde a los volumenes globales procesados de 1 a 4, respectivamente. Dicho estudio es el más representativo y actual realizado sobre la minería del cobre hasta la fecha. Fue conducido de acuerdo a los estándares ISO y reemplaza información fragmentada, no representativa,y desactualizada que había en la literatura.La información del estudio se reunió entre 2005 y 2009, y en aquellos casos en que se presentaron inconsistencias, fue medida o revisada nuevamente, utilizando la misma metodología. La información de base del estudio, así como la metodología empleada, las condiciones de borde, y las asignaciones están plenamente documentadas y son transparentes, lo que es clave para este tipo de estudio, ya que el objetivo final es que los resultados sean utilizados por diversas industrias para evaluar sus estrategias ambientales, así como asitirlos en la selección y utilización de materiales. Las contribuciones de las emisiones a los seis efectos considerados por ISO se refieren a los alcances uno a tres. Las etapas de mina y concentradora en la ruta pirometalúrgica dominan la contribución a la demanda primaria de energía (PED), potencial de calentamiento global (GWP), y eutroficación (EP), mientras que las etapas de pirometalurgia y refinación dominan los otros tres efectos evaluados, la acidficación (AP), el potencial de generación fotoquímica de ozono (POCP), y la depleción de la capa de ozono (ODP). Uno de las 14 fundiciones analizadas se desvía significativamente de la media, incrementando el valor medio de AP. La generación de energía eléctrica (alcance dos) juega un rol determinante en la contribución a GWP, como podría esperarse. Por ejemplo los tres mayores productores via la ruta hidrometalúrgica tienen un mix de abastecimiento de electricidad basada en combustibles fósiles. Los asignación de efectos de los subproductos como el ácido sulfúrico, el molibdeno, y los barros anódicos, se efectúa mediante diversos métodos, todos los que son contabilizados como créditos a los efectos producidos por la producción de concentrados y cátodos, con objeto de no realizar una doble contabilidad. Ello significa que la producción de cátodos via hidro y piro metalurgia no puede ser comparada. El uso de chatarra en las fundiciones reduce la generación de los seis efectos considerados en la producción de concentrados. Palabras clave: Inventario, Ciclo, Vida, Cobre, Primario

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From foundations to the building - a blueprint of LCA in Mexico Nydia Suppen Reynaga* *CADIS-Centro de Análisis de Ciclo de Vida y Diseño Sustentable México

[email protected]

Abstract The LCA methodology is generally conceptualized with a tinge of academic and research, which indeed is a very important and necessary ground , but LCA has also proven to be a solid methodology for implementation in industry and government. The aim of the presentation is to outline (blueprint), "from the foundation to the building―, the efforts and achievements in the implementation of LCA in the construction sector in Mexico, from the formation of consolidated academic groups, successful ―green housing‖ construction projects to public policies, thus contributing to the improvement of the environmental performance of the sector.

975


The Bhutan-UN International Project to Create a New Paradigm for Sustainable Development Gregory A. Norris* * Harvard School of Public Health, 401 Park Drive, 02215, Boston, MA, USA

++1 207 351 1897 [email protected] URL: http://handprinter.org New Earth (www.newearth.info)

Abstract Purpose

The Government of Bhutan, in collaboration with the Secretary General of the United Nations, has launched a 2-year international effort to develop and define details of a "new development paradigm" which is focused on human well-being and on the well-being of all life on earth, "based on a healthy balance among thriving natural, human, social, cultural, and built assets, and recognizing ecological sustainability and the fair distribution and efficient use of resources as key conditions for the new model." Methods

An international Working Group of roughly 50 experts from around the world has been convened in order to undertake this work, and a detailed workplan has been established. The author of this paper is a member of the International Working Group. The Working Group will prepare detailed documentation, including thorough literature reviews and examinations of existing best practices, on the actual, practical workings of the new model. The outcomes and results of the Working Group will be presented to the United Nations General Assembly in 2013 and 2014. The first year‘s work will focus on the ultimate goal, purpose, and context of the new development paradigm ― namely to promote human happiness and the wellbeing of all life forms. The second year will focus on key conditions required to achieve that goal, including the measurement and accounting systems required to assess sustainability, wellbeing and happiness, and the appropriate governance, resource, investment, financial, trade, and regulatory policies and mechanisms appropriate for such a development model.

Results

This international project to develop a new paradigm for Sustainable Development, focused on human wellbeing and the well-being of all life, is likely to be of broad general interest to many practitioners and users of Life Cycle Assessment. There are also likely to be specific ways that LCA can contribute to and be supported by the paradigm. The presentation will provide an overview of the motivation, background, workplan, and progress of this international effort. It will highlight connections to the methods and practice of Life Cycle Assessment, and implications for the future of our field.

Conclusions

I am submitting this abstract for consideration as a general presentation, and also perhaps for consideration as a possible ―keynote‖ presentation, in case the conference organizers believe it would be of high and general interest to the participants. Key words: Sustainable Development, Human Well-being

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Interoperability in LCA: problems and solutions Sangwon Suh* * Bren School of Environmental Science and Management University of California

Santa Barbara, CA 93106-5131 Office Phone: (805) 893-7185 Fax: (805) 893-7612 Email: [email protected]

Abstract Building a global Life Cycle Inventory (LCI) database from scratch with a harmonized method and wide process coverage would require significant resources. Therefore, it is worth examining to what extent existing LCI datasets can be adapted to form the basis of a more common database. This study examines the opportunities and challenges of transforming the existing US LCI database to meet the intrinsic (e.g. assumptions, methods, completeness) and extrinsic (e.g. data format) requirements of ecoinvent 3. Nineteen US LCI datasets were selected for transformation. Datasets were first converted in batch from EcoSpold 1 to EcoSpold 2 format using an automated tool based on a Python script. Other changes, necessary to conform with ecoinvent standards, were made manually, such as changing activity and flow names, mapping dummy exchanges, and creating global reference datasets. To address data gaps and other data quality issues, each dataset was assessed against ecoinvent 3 data quality guidelines, and missing information was noted. When available, public reports for the US LCI datasets were examined to fill in data gaps. Datasets were also compared against similar processes in ecoinvent to see if there were any significant flows omitted; missing flows were filled by using estimates for these exchanges from similar processes already within ecoinvent. The automated tool for data exchange format conversion saved time and reduced the potential for error. Even so, a nontrivial amount of time and research was spent on the manual changes needed to conform to ecoinvent standards. Addressing data gaps and other data quality issues also required considerable effort. In general, US LCI datasets were missing the following data required by ecoinvent 3: land use, water, and infrastructure exchanges; production volumes; uncertainty and data quality information; and adequate documentation of system boundaries, methodology, and process technology. Much of this missing data could be filled by examining available reports, using ecoinvent data as proxies, or conducting independent research. However, in some cases, such as for water data, adequate estimates could not be determined based on readily available materials

977


Contributing To Rio+20: A Unep/Setac Life Cycle Sustainability Assessment Approach Valdivia, S. (1), Ugaya C.M.L. (2), Hildenbrand, J. (3), Traverso, M. (4), Mazijn, B. (5), Sonnemann, G. (6) (1) United Nations Environment Programme, France (2) Technical Federal University of Parana, Brazil (3) Chalmers University, Sweden (4) TU Berlin (5) Ghent University (6) University of Bordeaux

Abstract The aim of this abstract is to present the UNEP/SETAC publication ―Towards a Life Cycle Sustainability Assessment (LCSA)‖ which contributes to the United Nations Conference on Sustainable Development (Rio+20) in 2012 by introducing LCSA and showing how it can play a crucial role in moving towards sustainable consumption and production. The publication shows how the three Life Cycle techniques (environmental) LCA, Social LCA and Life Cycle Costing can be combined on an overarching LCSA by evaluating the characteristics of each phase for each LC technique. In defining the goal and scope of an LCSA, for example, different aspects should be taken into account to establish the aim of the study and the functional unit, system boundaries, impact category and allocation. Then, the data to be collected for the Life Cycle Sustainability Inventory (LCSI) can be either in a unit process or on organizational level, and they can also be quantitative or qualitative. Life Cycle Sustainability Impact Assessment (LCSIA) should consider the relevance of the impacts as well as the perspective of stakeholders. The interpretation should not add up the results, but rather evaluate them conjointly. To clarify the approach, a case study is presented to evaluate three types of marbles according to the method proposed. The authors have identified following areas that need more development: data production and acquisition; discussion about LCSA criteria (e.g. cut-off rules), definitions and formats of communication and dissemination of LCSA results; and the expansion of research and applications combining (environmental) LCA, LCC and S-LCA. The authors have also pointed out the necessity to develop more examples and cases. The application showed that, LCSA is possible and should be pursued, nevertheless, more efforts should be made to improve the technique and facilitate the studies in order to contribute to more sustainable consumption and production.

Keywords: Sustainability, life cycle, social LCA, life cycle costing, Rio+20

Acknowledgements The authors of this article would like to thank the other co-authors of the publication ‗Towards a Life Cycle Assessment of Products‘, Walter Klöpffer, Matthias Finkbeiner, Andreas Ciroth, Siddhart Prakash and Gina Vickery-Niederman, as well as the members of the International Life Cycle Board of the UNEP/SETAC Life Cycle Initiative for their support. 978


References [1] Capitano C, Traverso M, Rizzo G and Finkbeiner M (2011). Life Cycle Sustainability Assessment: An Implementation to Marble Products. Proceedings of the LCM 2011 Conference. Berlin, 29–31 August 2011, www.lcm2011.org [2] Finkbeiner M, Schau E, Lehmann A and Traverso M (2010). Towards life cycle sustainability assessment. Sustainability, 2(10), 3309–22; open access doi:10.3390/ su2103309. [3] Franze J and Ciroth A (2011). A comparison of cut roses from Ecuador and the Netherlands. Int J Life Cycle Assess, (16)4, 366–79. [4] Guinée JB, Gorrée M, Heijungs R, Huppes G, Kleijn R, Koning A de, Oers L van, Wegener Sleeswijk A, Suh S, Udo de Haes HA, Bruijn, H de, Duin R van, Huijbregts, M.A.J. (2002). Handbook on Life Cycle Assessment. Operational Guide to the ISO standards. I: LCA in perspective. IIa: Guide. IIb: Operational annex. III: Scientific background. Kluwer Academic Publishers, Dordrecht. [5] ISO 14040 (2006). Environmental Management – Life Cycle Assessment – Principles and Framework. International Organization of Standardization. [6] ISO 14044 (2006). Environmental Management – Life Cycle Assessment – Requirements and Guidelines. International Organization of Standardization. [7] Klöpffer W (2008). Life cycle sustainability assessment of products. Int J Life Cycle Assess, 13(2), 89–95 [8] Poulsen P and Jensen A (eds). (2004). Working Environment in Life cycle Assessment. SETAC Press, Pensacola [9] Swarr T, Hunkeler D, Klöpffer W, Pesonen H-L, Ciroth A, Brent AC and Pagan, R. (2011). Environmental Life Cycle Costing: A Code of Practice. SETAC Press, Pensacola. [10] Traverso M, Finkbeiner M, Jørgensen A and Schneider L (2012). Life Cycle Sustainability Dashboard. Article first published online in journal of Industrial Ecology, 12 July2012 by Yale University DOI: 10.1111/j.1530-9290.2012.00497.x [11] UNEP/SETAC (2009) Guidelines for Social Life Cycle Assessment of Products. 103p. [12] UNEP/SETAC (2011a) Towards Life Cycle Sustainability Assessment. 65p. [13] UNEP/SETAC (2011b) Global Guidance Principles for LCA Databases.157p. [14] UN (1992), Rio Declaration, available at http://www.un.org/documents/ga/conf151/aconf151261annex1.htm First Edition: 2012-05-29

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ROUND TABLE

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PCR Guidance Development Process and its Importance to the Latin American Region Carolina Scarinci1,* - Wesley Ingwersen2 - Vairavan Subramanian3 - Claudia Peña1 1

Research Centre for Mining and Metallurgy (CIMM), Av. Parque Antonio Rabat 6500, Vitacura, Santiago, Chile

2

US EPA Office of Research and Development, USA

3

PRé North America Inc., USA

++56 02 5805323 *[email protected]

Abstract Environmental product declarations (EPD) are being increasingly used to report quantified environmental information of products based on their life cycle(Ingwersen and Stevenson, 2012). ISO 14025 mandates the development of product category rules (PCR) to set guidelines on how to generate and report such environmental information(ISO, 2006). Existing product claim standards and programs fail to provide sufficient specificity, resulting in duplicate and inconsistent PCR(Subramanian et al., 2012). This results in EPDs whose comparability is limited, thereby threatening the legitimacy of environmental labels and product claim comparisons. In response to this situation, multi-stakeholder organizations such as the PCF World Forum‘s PCR Roundtable and Taskforce and the American Center for LCA‘s PCR Committee worked in tandem to initiate a collaborative effort to develop a PCR Guidance that aims to supplement existing LCA-based product claim standards(Ingwersen et al., 2012). This Guidance seeks to improve alignment, comparability and the credibility of environmental claims. This initiative, which consists of more than 50 organizations from 14 countries and regions, was launched in early 2012with guidance from a special session in the LCA XI Conference in September 2011 in Portland, USA (Ingwersen et al., 2012). The first draft of the guidance was presented in a special session in the LCA XII conference in September 2012 in Tacoma, Washington, USA(Subramanian and Ingwersen, 2012). This paper presents the main outcomes and issues that were discussed in the LCA XII Conference. One novel concept is the ability to create a single ―unified‖ PCR with elements that accommodates fixed and flexible content that can serve multiple product declaration standards, different technologies, and different geographical conditions, thereby eliminating the need to invest in program and standard-specific PCRs. We also determine the importance of the Guidance for advancing sustainable development in Latin America. The feasibility of using EPDs as information modules will determine the utility of environmental claims from this region in the global arena. Furthermore, the selection and modeling of impact category indicators can be critical for the consideration of site-specific impact over global impacts, where relevant. Finally, additional discussion is encouraged on the incorporation of social and economic aspects into product declarations.

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Keywords: product category rules, alignment, environmental product declaration, labeling, PCR

1 Introduction Globally there is an increasing number of initiatives to quantitatively report the environmental performance of goods and services based on a life cycle assessment (LCA) (Ingwersen and Stevenson, 2012). Programs have been developed to provide end-consumers and business partners with information about the sustainability of products in the form of both single-criteria claims, such as product carbon footprint (CFP) and water footprints, and multi-criteria claims, such as environmental product declarations (EPD)(Subramanian et al., 2012). These programs require rules of standardization to define the requirements of data quality, system boundaries, allocation and impact category methodology, among others, so that fair comparison between claims is ensured (Del Borghi et al., 2008). These rules are known as ‗supplementary requirements‘ in PAS2050 (BSI, 2011), ‗product rules‘ in Greenhouse Gas Product Accounting and Reporting Standard (GHG Protocol, 2011), ‗carbon footprint product category rules‘ in the draft version of the ISO product carbon footprint standard, ISO/DIS 14067, and ‗product environmental footprint category rules‘ in the Product Environmental Footprint Guide (EC JRC, 2012). ‗Product Category Rules‘ (PCR) is the official term used in the ISO 14025 standard and this term may also be used to encompass all of the aforementioned rules, which all serve the purpose of providing product category specific rules for LCA-based claims. Programs to develop EPDs have been in place for more than a decade in Northern Europe, and demand for this type of product information is now growing in other parts of the world (Fava et al., 2011). Programs that permit manufacturers to develop EPDs are now present in Europe, Asia, and North America (Ingwersen and Stevenson, 2012). It has been noted that, due to the global supply chains, eco-labeling regulations or certification requirements for consumer products in the developed world can potentially harm the small or medium-sized enterprises (SMEs) in developing countries, where they account for a large part of employment (UN DESA, 2007). Furthermore, the expansion of labeling programs to developing nations in Africa and Latin America without the correct adaptation to geographical conditions can also affect the local economies. The LCA-based standards themselves fail to provide sufficient specificity to ensure that consistent assumptions are made in the development of PCRs. Furthermore, ISO 14025 does not designate a single institution to oversee the development and regulation of PCRs. Thus, programs often develop new PCRs, resulting in duplication and inconsistency in PCR development(Subramanian et al., 2012), which in turn results in claims whose comparability is limited, thereby threatening the legitimacy of environmental labels and product claim comparisons.In response to this situation, multi-stakeholder organizations such as the PCF World Forum‘s PCR Roundtable and Taskforce54 and the American Center for LCA‘s PCR Committee 55, came to a consensus that more guidance on PCRs would benefit all parties involved and improve legitimacy of environmental declarations (Ingwersen et al., 2012). Early in 2012, a collaborative effort was launched by the American Center for LCA‘s PCR Committee to develop a PCR Guidance that aimed to supplement existing LCA-based product claim standards. This effort, originally a sub-committee, evolved into a grassroots, open, international, 54 55

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transparent and collaborative effort called the ‗Product Category Rule Guidance Development Initiative‘ 56. This initiative, which consists of more than 40 organizations (academia, civil society, trade associations, program operators, standard developers, consultants, etc.) from 14 countries and regions, presented the first draft of the Guidance in the PCR special session at the LCA XII Conference in Tacoma, in September 2012 (Subramanian and Ingwersen, 2012). The public consultation of the document, which is currently in progress, will end on March 1st, 2013. The Guidanceis expected to be publishedin April 2013. This Guidance seeks to improve alignment among PCRs, so that claims are consistent and comparable. The Guidance makes recommendations for defining product category rules and assembling stakeholder groups to draft PCRs. It also provides recommendations on mechanisms for PCR alignment, including creating unified PCRs that overcome differences between competing PCRs for the same product category. The Guidance describes required elements of PCR, including LCA and additional information components, recommends best practices for PCR creation, and suggests procedures for reviewing and publishing PCRs. It sources these guidance rules from a range of existing programs, standards, and publications and provides additional visionary guidance to remain relevant in this dynamic field. The annexes of the Guidance include a template for PCR creation and a comparison of rules for LCA from all product claims standards and programs. This paper presents the main outcomes in the development of the PCR Guidance. The first section of this paper will describe the main concerns of the participants in the PCR special session in Tacoma. Later, this paper will determine the relevance of the Guidance for the sustainable development of Latin America due to the impact of labeling programs around the world over this region. To conclude, a final remark will be made on the importance of the involvement of developing nations in the global discussion over PCR development and alignment.

2 Discussion 2.1 PCR Guidance Special Session at LCA XII Conference

A special session was organized at the LCA XII conference, in Tacoma, Washington, USA on September 25th, 2012, to update the LCA community on the roughly 5-month progress made in the writing of the Guidance. In acknowledgement of the wide-spread interest in the development of PCR Guidance and the importance of it to the LCA community, the session took the place of the first session in the conference, right after the plenary. It was attended by roughly 100 participants from academia, government, civil-society, program operators, trade associations, industry, and consultants. This special session was a follow-up to the previous special session in LCA XI conference, in Chicago, Illinois, USA on October 4, 2011, where over 120 participants reaffirmed the need for a PCR Guidance (Ingwersen et al., 2012). The special session in Tacoma had three core purposes: to communicate the contents of the PCR Guidance; to present the process through which the Guidance was created; and to discuss selected issues with the LCA community that relate to the Guidance(Ingwersen et al, 2012b). Here are some issues that were discussed: 56

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A novel concept from the Guidance is a ―Unified PCR‖ – one PCR for a product category for the entire world. It has fixed and flexible conents that allows it be used across different product claim standards and in different countries. What are your thoughts on this concept? A participant, who is also a manufacturer of products, stated that this is an excellent idea. Given that they manufacture the same product in US, Asia, and in UK, it would be ideal not to model three different times, but to modify the model to accommodate the local situation. Another participant appreciated the concept, but doubted its feasibility given many complexities. Several more, agreed that it was a great idea. One participant, with prior experience in creating PCRs, stated that the unified PCR is essential due to the global supply chains. It was stated that in the near term, it is acceptable to have highly specific PCRs, but when moving on to the next level, unified PCRs are the way forward. Based on the personal experience of that participant in creating one such PCR that resembled a unified PCR, it was noted that it is very time consuming to deal with nuances between countries, programs, other modeling rules. Another participant statedthat we need to get all program operators to the table and get them to agree on a lot of things. With reference to organizational responsibility, do PCRs need to have an owner associated with it? If so, what should be conditions of ownership? If a PCR is adapted from another PCR, should there be a fee be associated with it? These are legal questions that each organization deals with on their own, one participant responded. It also varies on a case by case basis and on an organization by organization basis. Copyrighting and licensing are business decisions, stated another participant. One stated that adaption should not be fee based, as it would reduce interest and commitment in adapting and harmonizing PCRs. ISO 14025 states that every PCR should consider harmonization as a first step and a fee will deter that. Another participant suggested that all PCRs be put in the public domain without any copyright. Not all LCA-based product claim standards require program operators. The term PCR comes from of 14025, which requires program operators to create a PCR. If a party is interested in creating a PCR and is not a program operator, should this party conform to some basic requirements? Should any organization be allowed to develop PCR's?

One participant stated that the Guidance should provide such basic requirements. Another participant noted that stakeholders should be sufficiently represented during the PCR development process. Without basic requirements, what is the assurance that the interested party undertook necessary measures to ensure that all stakeholders were represented? It was suggested by another participant that a single organization without any ―status approval‖ may not be neutral and might tend to favor the organization that commissioned the PCR. Therefore, it is pertinent that any organization that intends to create a PCR be a neutral party without any vested interests in the PCR development process. Another participant agreed that a neutral party would be ideal but doubted its practicality; and therefore suggested the use of a transparent process as a compromise. It was stated by another that a neutral third party almost always doesn‘t have the details, and the industry does always have the LCA knowledge, so working together seems to be the best option. Currently, the program operator serves the role of a neutral third party and having them follow a transparent process seems like a realistic option. Another participant suggested that if the Guidance created a set of decisions that industry needs to make, then it would be easy for the third party, which has limited knowledge of the industry, to make decisions.

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2.2 Importance of the Guidance to the Latin American region.

Although the Guidance itself, if widely adopted, will likely improve consistency among PCRs, there are a number of other considerations for promotion of more global alignment, especially in order to engage stakeholders in global regions such as Latin America, where LCA and PCRs are just beginning to get a foothold. Better networks that connect program operators internationally, as well as interested stakeholders, will help educate the public and prevent duplication of efforts in PCR development. Tools that enable easier creation of PCRs and that facilitate translation across languages will expedite the PCR creation and adaptation process. The expansion of publically-available life-cycle inventory data is a necessary requirement to enable claims from sectors and regions where data is relatively absent. Following the principle of modularity for EPDs set in ISO 14025, emerging countries implicitly receive an important role in the development of PCRs. PCRs can be created for raw materials, parts, components and other inputs that are used in the manufacture or assembly of products (ISO, 2006). EPDs of materials elaborated using these PCRs can be used as information modules for the creation of EPDs of products. The provision of extensive guidance on how to combine EPDs as information modules could determine the value and usefulness of environmental claims in Latin American countries for B2B operations at an international level, due to the fact that a considerable amount of export from that region corresponds to raw material and agricultural products. On the other hand, there are still fears that certification schemes applied in international trade act as a barrier to market access. However, there are numerous ways to counteract the possible negative consequences for regions with less experience in LCA-based claims. Ingwersen et al. (2009) presents recommendations for the establishment of an government-sponsored EPD program in Costa Rica that are potentially relevant for other countries in Latin America. These include the development of a national LCA program, the early involvement of relevant sectors, especially those catering to international markets with potential interest in LCA-based claims, technical assistance for industry and financial support for SMEs, and promotion of the program to potential buyers in international markets by public entities like export promotion agencies. Taking careful steps to support the growth of LCA-based claim programs that are both educational, while at the same time assist in the creation of claims that are rigorous and accurate, and by providing assistance to all producers so that they can be competitive in international markets, LCA-based claims can be designed to be successful in Latin America. It is a requirement that the PCR Guidance provides requirements and recommendations on the selection and modeling of impact category indicators, as this can be critical for the consideration of site-specific impact over global impacts, where relevant. This was one of the reasons why fixed and flexible components where defined in the PCR Guidance. In this way, PCRs can become more robust, and comparability between LCA-based claims can be ensured. The development of unified PCRs with a global scope, should consider that geographically specific (primary and secondary) data or information modules can be used in order to account for regional-specific impacts. Both ISO 14025:2006 and the PCR Guidance state that geographical

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differentiation shall not be a reason for the development of an alternative PCR, but it certainly can be a reason for adapting existing PCRs. Finally, further discussion is encouraged on the incorporation of social and economic aspects into product declarations, in line with the global efforts towards sustainable consumption and a green economy (UNEP, 2012).

3 Conclusions The additional guidance provided in the recently developed draft of the PCR Guidance enables the development of consistent product category rules and their equivalent in other life cycle-based product claim standards. There are still many concerns about PCR development among the LCA community, which were reflected in the discussion held among people from from academia, government, civil-society, program operators, trade associations, industry, and consultants at the special session at the LCA XII conference, in Tacoma. One of these is the ability to create a unified PCR with flexible elements that can serve the purpose of multiple product declaration standards and geographical specificity, eliminating the need to invest in multiple PCR development. However, potential obstacles remain to be solved that particularly concerns the Latin American region such as the use of EPDs as information modules, the adaption of PCRs to geographical conditions, the selection of secondary data sources, and the incorporation of the other aspects of sustainability apart from the environmental one. Consequently, it is of paramount important that developing nations become active in the development of global labeling standards and guidance, so that they contribute with examples and case studies that highlight the specific requirements of the region.

4 Reference BSI (2011) PAS 2050:2011 - Specification for the assessment of the life cycle greenhouse gas emissions of goods and services. UK, British Standards Institution,. DEL BORGHI, A., GAGGERO, P., GALLO, M. & STRAZZA, C. (2008) Development of PCR for WWTP based on a case study.The International Journal of Life Cycle Assessment, 13, 512-521. EC JRC (2012) Product Environmental Footprint (PEF) Guide.Ispra, European Commission Joint Research Centre. FAVA, J., BAER, S. & COOPER, J. (2011) Green(er) Product Standard Trends in North America. Journal of Industrial Ecology, 15, 9-12. GHG PROTOCOL (2011) Product Life Cycle Accounting and Reporting Standard. Washington and Geneva, World Resources Institute, World Business Council for Sustainable Development. INGWERSEN, W. & STEVENSON, M. (2012) Can we compare the environmental performance of this product to that one? An update on the development of product category rules and future challenges toward alignment.Journal of Cleaner Production, 24, 102-108. INGWERSEN, W., SUBRAMANIAN, V., SCHENCK, R., BUSHI, L., COSTELLO, A., DRAUCKER, L., EAST, C., HENSLER, C., LAHD, H. & RYDING, S.-O. (2012) Product category rules alignment workshop, October 4, 2011 in Chicago, IL, USA. The International Journal of Life Cycle Assessment, 17, 258-263. INGWERSEN, W. W., CLARE, S. A., ACUÑA, D., CHARLES, M. J., KOSHAL, C. & QUIROS, A. (2009) Environmental Product Declarations (Declaraciones ambientales de Producto, o EPDs): Introducción y recomendaciones para su uso en Costa Rica. Gainesville, FL, University of Florida Levin College of Law Conservation Clinic. ISO (2006) ISO 14025: Environmental labels and declarations - Type III environmental declarations Principles and procedures. Geneve, International Organization for Standarization,. SUBRAMANIAN, V. & INGWERSEN, W. W. (2012) Guidance Development for Product Category Rules.A 986


Special Session at the LCA XII conference. Tacoma. SUBRAMANIAN, V., INGWERSEN, W. W., HENSLER, C. & COLLIE, H. (2012) Comparing Product Category Rules from Different Programs: Learned Outcomes Towards Global Alignment. International Journal of Life Cycle Assessment, 17, 892-903. UN DESA (2007) CSR and Developing Countries: What scope for government action? Innovation Briefs.New York, United Nations Department of Economic and Social Affairs.Division for Sustainable Development. UNEP (2012) Green Economy: measuring progress towards a green economy. Draft working paper. United Nations Environment Programme

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Product category rules in emerging regions: the global trade of mineral raw materials Claudia Peña* – Kevin Harding *Ibero-American Network of Life Cycle Assessment

++56 2 3260183 [email protected] URL: rediberoamericanadeciclodevida.wordpress.com/ African Life Cycle Assessment Network University of the Witwatersand, Johannesburg, South Africa

[email protected] ++27 11 7177576 URL: estis.net/sites/alcanet/

Abstract The life cycle of products, which are mainly located in emerging regions of the World, starts when extracting raw materials from their primary sources (Sonnemann and de Leeuw 2006). Being part of the global supply and value chain of products, the way the rules for Life Cycle Assessment (LCA) of raw materials were defined, has significant implications for environmental, social and economic dimensions. The purpose of this article is present two approaches to define product category rules (PCR) of raw materials. The first is from the perspective of the producers or distributors of final products and secondary industry, which is widely located in developed countries. The second approach is from the perspective of local LCA experts who consider sustainability aspects under site-specific conditions. In this study, we specifically took mineral resources as the case study due to its massive impact in global trade. We based our work on official studies establishing recommendations for policy making in Europe and other OECD countries, taking into account their access to mineral raw materials (EU 2010) under a new scenario where emerging regions start to introduce environmental and socio-economic restrictions on exporting mining products (WTO 2010). According to the ISO standard 14025, PCR is a tool that has the potential to establish a basic framework to perform life cycle assessment and report environmental and sustainability indicators. These include carbonand water footprints of products, land use and other LCA indicators, as well as social and economic indicators.Therefore it is considered fundamental to set up common reference to globally traded products in a fair and adequate way. Hence, PCR provides a protective border for emerging countries to trade their raw material products (RICV-ALCANET 2011), taking into consideration life cycle sustainability aspects that will directly impact on their sustainable development. The two different approaches presented in this work are expected to raise awareness amongst policy makers in the developed and developing countries, about how emerging regions could introduce new elements to market behavior, while the life cycle sustainability assessment concepts are being adopted in these regions. This will also eventually affect final product design (for instance, putting an end to obsolescent commercial strategies) and prices, and consequently the pattern for sustainable consumption and production in the developed world. Key words: Life Cycle Assessment (LCA), Product Category Rules (PCR), emerging regions, natural resources, product competitivenes, sustainable development.

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References EU (European Union). 2010. Report lists 14 critical mineral raw materials. MEMO/10/263, 17/06/2010 Ramdoo, I. 2010. Implications of the EU Raw Materials Initiative on ACP Countries Status of the Mining Sector in Trade Negotiations. The Netherlands: European Centre for Developing Policy Managemnet (ECDPM). RICV-ALCANET (Ibero-American Network of LCA – African Network of LCA). 2011. Rio+20 Conference. http://uncsd2012.org/rio20/index.php?page=view&type=510&nr=278&menu=20 Accessed August 2012. Sonnemann, G. and B. de Leeuw. 2006. Life Cycle Management in Developing Countries: State of the Art and Outlook. Int J LCA 11, 123 – 126 Special Issue 1. WTO (World Trade Organization). 2010. http://www.wto.org/english/res_e/publications_e/wtr10_forum_e/wtr10_oecd2_e.htm Accessed August 2012.

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The development of Product Category Rules in order to ensure a Green Economy in emerging regions Carolina Scarinci1,* - Claudia Peña2 1

Chilean Network of LCA

2

Ibero-American LCA Network

*Corresponding author: [email protected]

Abstract Since the World Summit on Sustainable Development in Johannesburg 2002, where countries committed to sustainable consumption and production, an international race to develop eco-labelling programs and product claims schemes has begun, often led by big companies and consortiums. In emerging regions, this could jeopardize the local sustainable development, as many governments, short of resources and experience, might delegate these tasks to the private sector, potentially causing mishandling and abuse. It is recognized that the communication of the sustainability of products should be dissociated from the economic and commercial interests of big companies and consortiums. Product Category Rules (PCR) are identified as a key standardized tool to control product claim initiatives, projects and programs. Recently, the ‗Product Category Rule Guidance Development Initiative‘, consisting of more than 40 organizations from 14 countries, developed a PCR Guidance to supplement existing LCA-based product claim standards (Subramanian and Ingwersen, 2012). In this paper, we present the main elements in the development of PCRs that have an impact in developing countries, as they set the framework for sustainable consumption and production. Many of these elements, such as the definition of system boundaries, the selection of impact categories and additional information, are fully addressed in the PCR Guidance. Others, although discussed in the Guidance, still need further definition. Among these are the creation of a Global PCR repository, the geographical representativeness of the PCR committee, the adaptation of existing PCRs, and the use of information modules. As a final remark, a call is made on developing countries to engage in EPD programs and in the international discussion about PCRs, to prevent that local strategies of sustainable consumption and production are defined exclusively by private initiatives. Also, developed nations are called upon to acknowledge the potential risk and to collaborate by extending their global initiatives to the emerging regions. Keywords: product category rules, sustainable consumption, environmental product declaration, developing countries, green economy

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Introduction At the World Summit on Sustainable Development in Johannesburg 2002, countries committed themselves to promote sustainable consumption and production (Tukker et al., 2008). The World Business Council for Sustainable Development, who is a key reference for industry in sustainability matters, indicated that the market should be the primary means to reach a sustainable world (Holliday and Pepper, 2001). This can be achieved only if purchasers are informed about the sustainability of the products they buy. For this reason, private companies who manufacture consumer goods started to develop initiatives to quantitatively report the environmental performance of goods and services, based on a life-cycle assessment (LCA), as a way to promote sustainable consumption. Programs have been developed around the world to inform consumers about the sustainability of products in the form of both single-criteria claims, such as product carbon footprint (CFP), and multi-criteria claims, such as environmental product declarations (EPD) (Subramanian et al., 2012).

Governments in developing countries, who only recently and in a very slow pace incorporated sustainability in their public agenda, may entrust the initiatives on sustainable consumption to the private sector to accomplish their own goals in social and environmental areas. These initiatives not only fulfil the expectations of society regarding green economy, but also help governmental agencies, who lack monetary resources, knowledge and experience, to develop extensive environmental claim programs. Nevertheless, when these initiatives are promoted only by large transnational companies and powerful consortiums, there might be a risk of a conflict of interest, as they might orientate programs to their economic and commercial objectives. Companies with huge resources for research in LCA and significant capacity to implement and communicate extensive environmental declaration programs in developed countries, might set up the framework for sustainable consumption and production in emerging regions, without the relevant consideration of local aspects. As public organizations in emerging regions do not have comparable resources and knowledge, they remain not fully involved, resulting in a potential damage for their economy and sustainable development. There is a risk that, by establishing models and patterns of reference that entail their own economic interests, companies might distort the implementation of the existing methodological standards for sustainable consumption and production. In this scenario, these companies might determine what environmental impacts are the most relevant in these regions, what emissions need to be considered, which are their relationship to site-specific conditions, what is more significant for different industrial sectors, which activity bears the greatest burden, which allocation scheme should be used for a life-cycle sustainability assessment, etc. In this context, consortiums and big companies might become judges in the development of sustainable policies. For all the above, it has been noted that developing countries, through governmental agencies, should engage in sustainable production and consumption policies, and develop eco-labelling programs directed towards the public objectives of economic, environmental and social sustainability. Although EPDs (ISO, 2006), and other LCA-based product claims (EC JRC, 2012, BSI, 2011, GHG Protocol, 2011), require rules of standardization to define the methodological requirements, they fail to provide enough guidance to avoid the aforementioned mismanagement of the methodology. ‗Product Category Rules‘ (PCR) in ISO 14025, ‗supplementary requirements‘ in PAS2050 (BSI, 2011), ‗product rules‘ in GHG Protocol (GHG Protocol, 2011), ‗carbon footprint product category rules‘ in the draft version of ISO/DIS 14067, and ‗product environmental footprint

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category rules‘ in the Product Environmental Footprint Guide (EC JRC, 2012), set the requirements of data quality, system boundaries, allocation and impact category methodology, among others, so that fair comparison between claims is ensured (Del Borghi et al., 2008). Currently, PCRs are being developed in an uncoordinated manner among programs, resulting in duplication, inconsistency and limited comparability of claims (Subramanian et al., 2012). In response to this scenario, a collaborative effort was launched early in 2012 by the American Center for LCA‘s PCR Committee to develop a PCR Guidance that aimed to supplement existing LCA-based product claim standards (Subramanian and Ingwersen, 2012). The ‗Product Category Rule Guidance Development Initiative‘ 57 consists of more than 40 organizations from 14 countries. The PCR Guidance gives recommendations on five aspects of PCRs: steps before the development of the PCR; elements included in a PCR; the review process; publishing a PCR; and use of the PCR. This paper aims to present the main elements of PCR development, which were addressed in the PCR Guidance, and that can have an impact in emerging regions as they will determine the way sustainable consumption and production is defined. Final conclusions and recommendations are provided to engage developing countries in EPD programs and in the international discussion about PCRs.

Discussion The Guidance for Product Category Rule Development aims that ―PCRs can be developed in a consistent manner and used to support claims based on multiple standards‖ (Ingwersen and Subramanian, 2013). Thus, a unified PCR with fixed and flexible components is proposed, to serve different LCA-based claim standards, different technologies and different geographical scopes. Single unified PCRs for each product category would avoid PCR duplication and inconsistent claims. Here, we will discuss some elements of PCR development that are relevant to the sustainable development of the developing countries, and that either were directly addressed in the PCR Guidance or need further definition. The elements are grouped into 4 sections: preparation for PCR development, stakeholder involvement, PCR alignment and elements of the PCR. Preparation for PCR development

Based on the requirements of ISO 14025, there are four the steps to carry out before the creation of a PCR: identify a program operator; determine the product category; search for existing PCRs; and involve the appropriate parties (Ingwersen and Subramanian, 2013). The former is only appropriate when speaking of a type III environmental declaration, as GHG protocol, PAS 2050 and PEF do not require the existence of a program operator. The involvement of the appropriate parties is discussed in the following section. With regards to the definition of product category, a long discussion is still in place. Many programs require the use of systems of product classification to define the product category. These classification systems, such

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as UNSPSC58, CPC59, GPC60, ISIC61, NAPCS62, CPA63 and HS64, were designed in the past and updated for different purposes. Thus, although they allow for clarity and unequivocal grouping of products, as well as easy discovery of existing PCRs, they present certain limitations when trying to assign a product category to a single code because functionality is not the classification key (Ingwersen and Subramanian, 2013). The PCR Guidance suggests the use of system of product classification for the sake of organization, but recommends that this shall not be the single element to identify a product category. Only the correct definition of the functional unit will determine the amount of products covered by the PCR and the comparability of claims (Ingwersen and Subramanian, 2013). The search for existing PCRs has proven to be a challenging job for PCR developers due to the amount of emerging programs around the world, the sometimes limited advertising of published PCRs and the language differences among programs. The PCR Guidance recommends that a Centralized Global PCR Repository is created and appropriately maintained so that PCRs are made available at a single location, as well as at their program operator website (Ingwersen and Subramanian, 2013). Nevertheless, a PCR Library65 currently exists, although it only groups PCRs from program operators that are members of GEDnet. Here, it should be noted that there are still issues that need to be defined if a Global PCR repository is to be created. Among these, which organization(s) will be responsible for the administration and maintenance of such a platform, and how the platform will be funded. A fee could be charged for downloading PCRs. However, this is against the aim of the platform: to have PCRs fully available in a single location so that developers can search for existing PCRs and adapt them as appropriate. Another alternative could be charging a fee for publishing PCRs. However, if a membership fee is to be implemented for publishing PCRs, this might be a barrier for developing countries to include their PCRs into the Global PCR repository. Stakeholder involvement

The PCR Guidance recommends a mechanism for open consultation to involve all the relevant stakeholders at all four stages in the development of PCRs: prior to the development, during the development, during the review process, and while the PCR is active. In order to inform stakeholders about the status of the PCR document and to indicate when to make comments, the Guidance suggests that a centralized notification mechanism is used to send public notices to subscribed participants every time the PCR changes its status. Emerging countries are only beginning to take part in the development of PCR, so it is safe to say that subscribers to the centralized notification mechanism will most certainly be stakeholders from the developed world. There should be mechanisms in place to ensure that all stakeholders, with the relevant geographical representation, are invited to take part in the open consultation and not just leave it to the people that are interested and part of the LCA community to subscribe to the notification system. On the other hand, governments and NGOs from emerging countries should commit to get actively involved in the discussion. 58

United Nations Standard Products and Services Code – http://www.unspsc.org Central Product Classification - http://unstats.un.org/unsd/cr/registry/cpc-2.asp 60 Global Product Classification - http://www.gs1.org/gdsn/gpc 61 International Standard Industrial Classification - http://unstats.un.org/unsd/cr/registry/isic-4.asp 62 North American Product Classification System - http://www.census.gov/eos/www/napcs/ 63 Classification of Products by activity 64 Harmonized System 65 http://pcr-library.edf.org.tw/index.asp 59

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Similarly, the composition of the PCR committee, i.e. who drafts the PCR, should also account for geographical representativeness. PCR committees should be composed of representatives from industry, civil society, government and LCA experts (Ingwersen and Subramanian, 2013). However, it is important that if the PCR is meant to have a global scope, members representing the most relevant geographical area should be considered. So, for example, all efforts should be made to involve Mexico in the PCR committee for avocado, Ecuador for bananas, and Brazil for green coffee, etc., as those are the main exporter of each mentioned product (FAO, 2010). PCR alignment

A novel concept of a unified PCR is introduced in the Guidance, to refer to a single PCR for a product category that fulfils requirements for more than one program or standard, and adapts to all geographical areas and technologies (Ingwersen and Subramanian, 2013). If the PCR committee finds that a PCR for a product category already exists, they can suggest the program operator of the existing PCR creating a unified PCR. If that is not achieved, the PCR committee should adapt the existing PCR, aiming at minimum modification from the core rules. The reasons to adapt a PCR are detailed in the Guidance. The adapted PCR should explicitly refer to the original PCR. Although adapting PCRs is a step towards alignment, it is still unclear whether claims based on adapted PCRs are comparable. Due to the fact that the ―minimal amount of modifications‖ is not quantified in the Guidance, there can be doubts on whether the PCR is adapted or if it is a completely different, even competing, PCR. A solution could be to state that the minimal amount of modifications is that that ensures the resulting claim is still comparable. However, the reasons to adapt a PCR provided in the Guidance are, in many cases, changes to the core rules that will certainly result in claims with limited comparability. Examples of the reasons to adapt a PCR are the exclusion of unit operations that are major impact contributors or the selection of characterization models applicable to one geographical area but not to another. Elements of a PCR

Type III environmental declarations are primarily intended for use in business-to-business (b2b) (ISO, 2006). ISO 14025 states that declarations that do not cover all life-cycle stages have limited comparability. However, it should be noted that many b2b transactions involve raw materials or semi-finished goods, whose LCA are commonly cradle-to-gate due to numerous uses that these products may have. The Guidance recommends that cradle-to-gate should be the minimum system boundary for virgin products and gate-to-gate, for recycled products. Thus, the issue with system boundaries presented for raw material and semi-finished goods traded in developing countries is addressed in the Guidance. One of the principles of EPDs is modularity (ISO, 2006). It allows the use of LCA-based information for parts and components to elaborate EPDs for the final product. Therefore, the development of PCRs for materials, part and components is important, as they can be used as inputs in the PCRs for final products. Although no example of an EPD created by adding up PCR information modules actually exists, this can be a key in the development of the complete set of PCRs to cover all possible product categories. In this case, developing

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countries have an important role in the development of PCRs for raw materials and semi-finished goods, as they are the main suppliers of these products. The selection of the relevant impact categories and calculation of category indicators has proven to be a controversial issue in the development of the Guidance. It has been previously noted that the use of different LCIA methodologies provide potentially different results (EC JRC, 2010). The regional validity of the existing methodologies varies: global for impact categories such as climate change and ozone depletion and regional/local for other midpoint and endpoint categories. However, due to the fact that most product systems include activities at a global scale (global supply chains), the PCR should specify a single method to calculate the indicator for each impact category and each geographical region covered by the PCR (Ingwersen and Subramanian, 2013). Furthermore, given the subjective nature of weighting, this step should be avoided for environmental declarations, because a truly objective and universally agreeable weighting methods is not feasible (US EPA, 2006). Finally, ISO 14025 provides the possibility of including additional information in the EPD, which is not necessarily derived from LCA, LCI or information modules. The Guidance recommends including here the indicators that, up to date, have not been fully treated in LCA such as water use and scarcity, biodiversity and habitat, land use, persistence in environment, individual toxicity, etc. Although ISO 14025 refers to additional environmental information only, it should be noted that efforts should be made in order to incorporate information about social and economic aspects into EPDs, in line with the global efforts towards sustainable consumption and a green economy (UNEP, 2012).

Conclusion Given the important role that the private sector might have in the definition of eco-labelling programs and product claims schemes in developing countries, and provided the potential for conflict of interest and mismanagement, it is recommended that developing countries engage in EPD schemes under public control, preventing that these regulatory processes are defined exclusively by private initiative. The communication of the sustainability of products should be dissociated from the economic and commercial interests of big companies and consortiums, and should have the input from local organizations to understand the site-specific issues. To achieve this, we identified that Product Category Rules (PCR) are a key standardized tool to control product claim initiatives, projects and programs. As a result of our work, we discovered the issues in the development of PCR that can affect the emerging region. Although the PCR Guidance, developed to supplement existing standards on product claims, tackles many of them and limits the potential mismanagement of product claims, there are still aspects of the development of PCRs that need to be discussed. We believe the developing world has a key role in this discussion. Among the aspects that need further discussion about PCR development, there is the creation and administration of a Global PCR repository. A membership fee for program operators to enable publishing of their PCRs could be a viable solution, although this could be a limitation for the poorer developing nations.

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However, a fee structure could be designed so that different fees are applied depending on the country‘s ability to pay, which can be determined by the gross domestic product, or the human development index (UNDP, 2011), or any other defined by consensus. Furthermore, the regional representativeness of the PCR committee is of paramount important, in order to include site-specific issues in PCR development. National, or else regional, associations of LCA experts in emerging countries can overtake this role, as they are able to identify local and regional industry experts, provide their technical knowledge on LCA, and act as guarantors for public organisms. Given their non-profit nature, they would look after the correct implementation and development of EPD programmes. Alignment of PCRs and the development of a unified PCR is a novel concept that will certainly be investigated as soon as program operators start developing them. However, adaptation of PCRs seems to be a controversial issue and more guidance should be provided to understand the level of comparability among claims from adapted PCRs. The participation of emerging countries in the development of PCRs is strongly advised so that site-specific conditions are taken into account in product claims. Also, it is requested that the developed nations acknowledge the relevance of regional representativeness in the development of global strategies to promote sustainable production and consumption, and fair trading of goods and services.

References BSI (2011) PAS 2050:2011 - Specification for the assessment of the life cycle greenhouse gas emissions of goods and services. UK, British Standards Institution,. DEL BORGHI, A., GAGGERO, P., GALLO, M. & STRAZZA, C. (2008) Development of PCR for WWTP based on a case study. The International Journal of Life Cycle Assessment, 13, 512-521. EC JRC (2010) ILCD Handbook: Analysis of existing Environmental Impact Assessment methodologies for use in Life Cycle Assessment. Luxembourg, European Commission - Joint Research Centre - Institute for Environment and Sustainability,. EC JRC (2012) Product Environmental Footprint (PEF) Guide. Ispra, European Commission Joint Research Centre. FAO (2010) EXPORTS: Countries by commodity. [Online] Available at http://faostat.fao.org/site/342/default.aspx (accessed 4th February 2013). GHG PROTOCOL (2011) Product Life Cycle Accounting and Reporting Standard. Washington and Geneva, World Resources Institute, World Business Council for Sustainable Development. HOLLIDAY, C. & PEPPER, J. (2001) Sustainable through the market: Seven keys to success. Switzerland, World Business Council for Sustainable Development. 996


INGWERSEN, W. & SUBRAMANIAN, V. (2013) Guidance for Product Category Rule Development, version 0.9 (draft for public comment). The Product Category Rule Development Initiative. ISO (2006) ISO 14025: Environmental labels and declarations - Type III environmental declarations Principles and procedures. Geneve, International Organization for Standardization. SUBRAMANIAN, V. & INGWERSEN, W. W. (2012) Guidance Development for Product Category Rules. A Special Session at the LCA XII conference. Tacoma. SUBRAMANIAN, V., INGWERSEN, W. W., HENSLER, C. & COLLIE, H. (2012) Comparing Product Category Rules from Different Programs: Learned Outcomes Towards Global Alignment. International Journal of Life Cycle Assessment, 17, 892-903. TUKKER, A., CHARTER, M., VEZZOLI, C., STO, E. & ANDERSEN, M. M. (2008) Perspectives on Radical Changes to Sustainable Consumption and Production, Sheffield, UK, Greenleaf Publishing Ltd. U.S. ENVIRONMENTAL PROTECTION AGENCY (2006) Life Cycle Assessment: Principles and Practice. Cincinnati, Office of Research and Development. UNDP (2011) Inequality-adjusted Human Development Index (IHDI). [Online] available at http://hdr.undp.org/en/statistics/ihdi/ (accessed 80-02-2013). UNEP (2012) Green Economy: measuring progress towards a green economy. Draft working paper. United Nations Environment Programme

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ADDENDUM

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Consistent calculation of multiple system models and improved integration of regionalized data in a background inventory database Emilia Moreno-Ruiz, Bo Weidema, Gregor Wernet The ecoinvent Centre, 129 Ueberlandstrasse, 8600 Duebendorf, Switzerland.

[email protected]

Abstract

In modern Life Cycle Assessment (LCA), practitioners have to make several important choices to define their system model, e.g. whether to use substitution or allocation based on various properties, whether to use marginal or average flows, and how to deal with issues such as open-loop recycling. The ecoinvent database has traditionally provided only one system model. The ecoinvent database version 3.0 has been adapted to allow multiple system models to be created based on the same unlinked data. This allows comparisons between different models and offers new research possibilities, e.g. a more consistent application of consequential LCA. To achieve this, a system for indirect linking was implemented that can be adapted to follow various linking rules. Market activities serve as intermediary steps to link suppliers and consumers and linking rules can affect the way markets provide products. At the same time, the indirect linking approach allows a much more consistent and faster integration of regionalized data in the database. This facilitates the hosting and development of regional databases within the framework of the ecoinvent database. Data for specific regions or countries can be included into the ecoinvent framework in a step-by-step process where supply chains are always covered through global background data and then automatically updated as local data becomes available. Collaborations with partners in Canada, India, South Africa, Brazil and other countries are aiming to utilize this system to maximize the usefulness of their inventory data.

Results The unlinked database With the new v3structure the ecoinvent database is constructed and fed in a constant way,via the freeware ecoEditor. The data providers submit now to ecoinvent unlinked multi output datasets, meaning that the data provider has only to focus on modelling accurately, and following the guidelines of the v3, the activity he or she has data for. But let us explain what do we mean by ―unlinked and multi output‖ datasets. First, face to activities that produce co-product, the data provider does not have to face the painful exercise of deciding whether to allocate them, and using which criteria. So if the described activity generates several co-products, all of them will be detailed in the multi output inventory that the data provider has to submit to ecoinvent. Of course, there are datasets that only produce a reference product, and there is no by-product/waste to consider, and this is logically supported in the v3. The multi output datasets have to provide one reference product, that is pointed as being the economic driver of the activity, and as much by-products/wastes as needed. The by-products are other marketable products, but that do not by themselves justify the economic interest of the activity. The ecoinvent Centre does not provide an official definition for waste. We support the concept of material for treatment, as by-products/wastes that are not marketable as such, but need to be treated before supplying a market. Second, the unit process is generated and submitted as an unlinked activity. This is possible because in the v3activities generate products, and both concepts are distinct, and as such, bear different names. For example: the activity ―hard coal mine operation‖ generates the product ―hard coal‖. All specifications regarding geography and time validity remain within the activity. Thereby, a dataset is constructed as a list of inputs and outputs of products (intermediate exchanges) and exchanges to or from environment. The data provider is not obliged anymore to assess the origin of the intermediate exchanges from Technosphere. He or she does not have to know or guess where the inputs to the activity are coming from

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(in terms of which activity produces them, and where this activity is located), and what will be the fate of the byproduct/wastes generated out of it (to which waste treatment should them be directed).

Figure 34.Activity in ecoinvent v3 The possibility of providing unlinked datasets is ensured because ecoinvent has established an automatic linking in order to calculate the system models out of the unlinked datasets.This distinction between the unlinked ecoinvent datasets and the linked system models is new. In the ecoinvent database version 2, only one system model existed, following an attributional approach, using allocation rules for multi-output processes according to the recommendations of the individual data providers. The difference in version 3 is that there are now several system models, all of which are used to create fully independent and self-contained model implementations out of the same unlinked ecoinvent data.

Behind the linking: use of the markets The ecoinvent v3 database is organised in activities: transforming activities and market activities are the main ones. A transforming activity will be ―hard coal operation‖, where ―hard coal‖ is the reference product of the activity that represents the mining of the coal. Market activities represent consumption mixes in a specific geography. They are identified by the reference product they provide. For example, ―market for hard coal‖ is defined by its reference product ―hard coal‖. The name of the reference product of an activity (market or transforming) is then crucial: it will define to and from which market products are being directed.Market activities also harbour the generic transport modelling of the reference product to the demanding activities in the geographical boundaries of the market; as well as losses and stock changes.

Figure 35.Market activity in ecoinvent v3. The linking of the database in order to calculate the system models happens by default viathe market activities: a market will be linked to receive inputs from the transforming activities, located in the geographical boundaries of the market, and producing its reference product. Similarly, markets will provide the activities, locatedin their geographical boundaries, thatdemand its reference product as input. So the supply chain is automatically generated and assembled using the geographical localization of the activities. Otherwise, the data provider has also the possibility of defining a direct linking that avoids the market linking. This possibility is of interest in the case of products where the supplier is known. In that case, a direct link can be established between the activity producing a product, and the activity consuming it, regardless geographic locations. In that case, the market linking is avoided, and the necessary supply is withdrawn from the producing activity itself.

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Figure 36.Simplified example of linking via the markets in the v3 (only the references products are marked). The linking via the markets is behind the calculation of the system models, whatever the one the user decides to choose.

System models Two system models will be available in the v3.0 of the database: the Allocation default system model and the Consequential system model.As an ecoinvent database user, your first important choice is therefore to determine which system model you want to use, according to the goal and scope definition of your project. You shall be aware of which system model version you are using in your projects, and communicate this openly when talking about results based on these data. The system model Allocation defaultis attributional, meaning that uses allocation to deal with multi output activities, and considers average suppliers. It is traditionally the system model being provided by ecoinvent, except for the fact that now the allocation factors are provided by default by the ecoinvent Centre, and the data provider does not need to decide on them. The system model Consequential uses substitution (system expansion) to substitute by-product outputs and takes into account both constrained markets and technology constraints. Technology constraints are taken into account using the ―technology level‖ of the transforming activities (current, modern, old…). In the Allocation default system model, all providers are giving inputs to the market. In the Consequential system model, only the most competitive technology (modern) is unconstrained in growing market volumes (and only the least competitive (old) in decreasing market volumes).

Figure 37.Attributional and Consequential System models (decision onby-products).

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Integration of local datasets New regionalised data can be now easily integrated in the database. The data provider does not need to provide data for all necessary input from Technospherein order to legitimate the geographical location of his or her new local dataset. On the contrary, the system itself will withdraw from local markets the available local products; taking the missing ones from generic global markets systematically provided by the database. The unlinked database is updated constantly; each new calculation of the system models integrates the updated or new datasets. As newer regionalised datasets are stored in the database,the local supply chains that are constituted automatically using the linking viathe marketsget more specific data, without having necessarily to correct or update the existing inventories.

References

Weidema B P, Bauer C, Hischier R, Mutel C, Nemecek T, Reinhard J, Vadenbo C O, Wernet G. (2012). Overview and methodology.Data quality guideline for the ecoinvent database version 3. Ecoinvent Report 1(v3). St. Gallen: The ecoinvent Centre.

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