Green Chemistry Principles, Intro. to Environmental

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Materials for Slides (15, 20-29) from U. of Illinois Case Study notes PPT ... (Anastas, P. T.; Warner, J. C. Green Chemistry: Theory and Practice, Oxford University ...
Waste Water/Solid Treatment (Review) Green Chemistry Principles, Intro. to Environmental Regulations and Pollution Prevention

Lecture 4A Christine S. Grant, Ph.D. Professor of Chemical and Biomolecular Engineering North Carolina State University College of Engineering Raleigh, North Carolina, USA Materials for Slides (15, 20-29) from U. of Illinois Case Study notes PPT

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Sources of municipal waste and relationship to collection and treatment

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Block diagram of a complete wastewater treatment plant

Primary Treatment

(Enviromental Pollution and Control 3rd A.P. Vesilind, J.J. Peirce and R.F. Weiner 1990) CHE 475/575 Advances in Pollution Prevention: Environmental Management for the Future Spring 2003 by Dr. Grant

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Secondary Treatment

Microorganisms + Organics -> CO2 + new cells BOD5 10- 100 mg/l When microorganism 1st contact food a great deal of oxygen is required. (Environmental Pollution and Control 3rd A.P. Vesilind, J.J. Pierce and R.F. Weiner 1990) CHE 475/575 Advances in Pollution Prevention: Environmental Management for the Future Spring 2003 by Dr. Grant

Tertiary Treatment

Nitrogen Removal Nitrosomonas 2NH4+ + 3O2 -

2NO2 + O2

2NO2- + 2H20 + 4H+ Nitrobacter

2NO3-

(Enviromental Pollution and Control 3rd A.P. Vesilind, J.J. Peirce and R.F. Weiner 1990) CHE 475/575 Advances in Pollution Prevention: Environmental Management for the Future Spring 2003 by Dr. Grant

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CHE 475/575 Advances in Pollution Prevention: Environmental Management for the Future Spring 2003 by Dr. Grant

CHE 475/575 Advances in Pollution Prevention: Environmental Management for the Future Spring 2003 by Dr. Grant

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Solid Waste Disposal LandFills : Problems include - not enough space, leaching, toxic gas production, health problems (e.g., from rodents, insects) Oceanic Dumping: Illegal in the U .S .and many other countries Vitrification: Glass Formation (e.g. nuclear wastes) Incineration

Chemical Treatment Processes Treatment Process Classification

Applications

Neutralization

Neutralization of acidic or basic liquids to minimize corrosivity.

Precipitation

Removal of dissolved heavy metals or other dissolved hazardous inorganic contaminants.

Oxidation/reduction

Oxidative destruction of cyanide or organic contaminants. Change of valency of ionic constituents to render them less toxic or amenable to other treatment processes. Reduction of dissolved heavy metals to metallic form, and subsequent physical separation from solution.

Ion Exchange

Removal of dissolved ionic contaminants.

Stabilization

Stabilization of metal containing sludges by precipitation and encapsulation with cement.

CHE 475/575 Advances in Pollution Prevention: Environmental Management for the Future

Spring 2003 by Dr. Grant

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12 Principles of Green Chemistry* 1.

Prevention It is better to prevent waste than to treat or clean up waste after it has been created.

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Atom Economy Synthetic methods should be designed to maximize the incorporation of all materials used in the process into the final product.

2.

Less Hazardous Chemical Syntheses Wherever practicable, synthetic methods should be designed to use and generate substances that possess little or no toxicity to human health and the environment.

3.

Designing Safer Chemicals Chemical products should be designed to effect their desired function while minimizing their toxicity.

4.

Safer Solvents and Auxiliaries The use of auxiliary substances (e.g., solvents, separation agents, etc.) should be made unnecessary wherever possible and innocuous when used.

5.

Design for Energy Efficiency Energy requirements of chemical processes should be recognized for their environmental and economic impacts and should be minimized. If possible, synthetic methods should be conducted at ambient temperature and pressure.

(Anastas, P. T.; Warner, J. C. Green Chemistry: Theory and Practice, Oxford University Press: New York, 1998, p.30. By permission of Oxford University Press)

12 Principles of Green Chemistry*

7.

Use of Renewable Feedstocks A raw material or feedstock should be renewable rather than depleting whenever technically and economically practicable.

8.

Reduce Derivatives Unnecessary derivatization (use of blocking groups, protection/ deprotection, temporary modification of physical/chemical processes) should be minimized or avoided if possible, because such steps require additional reagents and can generate waste.

9.

Catalysis Catalytic reagents (as selective as possible) are superior to stoichiometric reagents.

10. Design for Degradation Chemical products should be designed so that at the end of their function they break down into innocuous degradation products and do not persist in the environment. 11. Real-time analysis for Pollution Prevention Analytical methodologies need to be further developed to allow for real-time, in-process monitoring and control prior to the formation of hazardous substances. 12. Inherently Safer Chemistry for Accident Prevention Substances and the form of a substance used in a chemical process should be chosen to minimize the potential for chemical accidents, including releases, explosions, and fires. (Anastas, P. T.; Warner, J. C. Green Chemistry: Theory and Practice, Oxford University Press: New York, 1998, p.30. By permission of Oxford University Press)

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Environmental Protection Agency Brief Introduction

z Created in 1970 during the Nixon Administration

– – –





Nixon wanted the support of environmentally conscious voters Executive order stressed comprehensive environmental management Agency initially staffed with bureaucrats from other agencies z experienced in planning, grant giving and technical assistance z not accustomed to an enforcement mentality Nixon appointed William Ruckelshaus as first EPA administrator – Nixon’s executive order stressed comprehensive environmental management – Ruckelshaus was a skilled law enforcer • Gave first priority to enforcement • Concerned most with public opinion • Believed alternate strategies would only produce results in the distant future • Shortchanged R&D, planning & tech. Assistance • Created confrontational relationships that still exist today State Programs Patterned after U.S. EPA CHE 475/575 Advances in Pollution Prevention: Environmental Management for the Future

Dr. Grant

Environmental Regulations Hazardous Substances •EPA listed wastes:source-specific, generic and commercial chemical products. •Has 1 of following 4 characteristic attributes: reactivity, ignitability, corrosivity or toxicity.

CHE 475/575 Advances in Pollution Prevention: Environmental Management for the Future

Dr. Grant

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Clean Air Act (CAA): 1963>1977 - Regulates the emission of hazardous air pollutants. - National Ambient Air Quality Standards (NAAQS): set acceptable concentrations of pollution in the atmosphere. • Set for 6 criteria pollutants: CO, Pb, NO2, ozone, SO2 and particulates , 10 mm standards. - New Source Performance Standards (NSPS) • for stationary sources: e.g., power plants, incinerators, petroleum refineries, sewage treatment plants, and smelters • Clean Water Act (CWA): 1977 - Requires at least secondary treatment for all publicly owned treatment works. - Must have at least 85% BOD removal • Toxic Substances Control Act (TSCA): 1979 -Banned use of CFCs • Pollution Prevention Act (PPA) CHE 475/575 Advances in Pollution Prevention: Environmental Management for the Future

by Dr. Grant

Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA): 1980

• Used to "regulate" existing (e.g., abandoned) dump sites. - Superfund created from special crude oil and chemical company taxes ($1.6 --> 8.5 billion trust fund). Used to deal with short-term emergencies and long term problems needing permanent solutions. - Superfund Amendments and Reauthorization Act of 1986 (SARA). • Resource Conservation and Recovery Act (RCRA): 1976>1980>1984 (Hazardous and Solid Waste Amendments) - Provides guidelines for prudent management of new and future hazardous substances. - Regulates generation, storage, transportation, treatment and disposal of hazardous substances.

CHE 475/575 Advances in Pollution Prevention: Environmental Management for the Future

Spring 2003 by Dr. Grant

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RCRA: TRANSPORTATION, STORAGE AND DISPOSAL

Pollution Prevention Definition • any in-plant practice that reduces or eliminates the amount and/or toxicity of pollutants which would have entered any waste stream or would otherwise have been released into the environment prior to management techniques such as recycling, treatment or disposal • Helps eliminate or decrease the volume or toxicity of – hazardous waste – other solid waste – wastewater – air emissions – energy usage

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Pollution Prevention IS • Source Reduction • In-process Recycling • Clean Technology • Raw Material Substitution • Preventative Maintenance IS NOT… • End-of-pipe Technologies • Pollution Control • Off-site waste recycling • Out-of-process waste recycling

Paradigm Shifts in Industry Pollution Prevention • More efficient use of materials is a goal of every company • Greater efficiency means less waste • Pollution prevention is everyone’s job • Pollution prevention is not just an environmental thing, it is a way of doing business Total Quality Management (TQM) • Started in America (Deming, Juran) • Adopted first by Japanese • Modified the bureaucratic model of organization • Created “Cross-functional management • Initial focus was on quality, cost and delivery (how these factors are influenced by all departments)

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TQM and Waste Minimization What they ARE Elements

TQM

Philosophy Customer Focus Approach Desired Outcomes

P2.

Emphasis on customer satisfaction, continuous Improvement

Emphasis on environmental quality & leadership, cleaner processes

Traditional customer

Customers, shareholders, regulators and community interests

Assess quality improvement opportunities in the company

Review design process; assess waste reduction & prevention opportunities

Continuous improvements; greater customer satisfaction, sales, employee morale

Less waste, reduced costs, improved regulations & public relations

TQM and Waste Minimization What they ARE NOT Elements Philosophy

TQM

Waste Min.

Inspection for defects

End-of-pipe pollution control

Customer Focus

Reactive approach to customer concerns

Minimal compliance

Approach

More inspection after operation More environmental controls; is completed better treatment and disposal

Desired Outcomes

Same defects in process but better inspection techniques

Same amount of waste generated, but managed more efficiently

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Federal Legislation that Encourages Pollution Prevention

Regulations for P2 • RCRA/HSWA • Community Right-to-Know Act-SARA 313 • Pollution Prevention Act of 1990 • Clean Air Act Amendments Applications for P2 • Production • Maintenance • Purchasing • Accounting • Engineering • Health and Safety

“EPA is...fundamentally shifting U.S. environmental protection strategy toward pollution prevention...this Administration is committed to making pollution prevention the guiding principle of all our environmental efforts.” -Administrator Carol Browner Hazardous and Solid Waste Amendments (RCRA) • Generators to demonstrate in biennial report their efforts to reduce the volume and toxicity of waste • Generators to certify on manifest that they have a program in place to reduce waste to the degree economically practical 1990 Pollution Prevention Act • Congress declared that the national policy of the U.S. is that: – Pollution should be reduced at the source whenever feasible (prevention); – Pollution that cannot be prevented should be recycled in an environmentally safe manner; – Pollution that cannot be prevented or recycled should be treated in an environmentally safe manner; and – Disposal or other release into the environment should be employed only as a last resort.

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Waste Management Hierarchy Preferred Order:

Pollution Prevention Waste Elimination Source Reduction In-Process Recycling/Reuse Process Substitution

lower Potential for Economic Benefits

Potential Liability

On-Site Recycling/Reuse Off-Site Recycling/Reuse

higher

Treatment including Incineration Disposal

Pressures on Companies to Adopt Pollution Prevention

• • • • • • • •

Legislation - Federal and State Public Information of Toxic Chemicals Public Demand for Zero Risk Increasing Costs for Treatment, Disposal, and Clean-up Valdez Principles CMA Responsible Care & API Regulatory Reporting & Enforcement Competition

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Is Pollution Prevention “Viable”?

One our largest pollution prevention project involved transforming a waste material into a saleable commercial byproduct. This project saves us about $500,000 per year. Of course saving money on this product grade improved profit margin and makes us more competitive. Chris Hallier,12 yr Process Engineer This is an important topic relevant to our business. We are always trying to reduce waste primarily to save money. We have additional incentive to find new treatment options in order improve public perception of our business to the community. Chris Hallier,12 yr Process Engineer I think pollution prevention is consistent with industrial competitiveness. At the plant I work at we have been able to convert some waste to fuel and found a product and buyer for some of the residue. Waste disposal can also become quite expensive and future regulations may credit trading benefits to companies. Companies may also be able to market their advances. Sara Perrin,Co-op at INVISTA - Wilmington, NC in Process Safety

Is Pollution Prevention “Viable”? Unless there is an economic benefit, pollution control and waste treatment will be the Is Pollution Prevention “Viable”? primary activities with existing processes. Green chemistry/engineering, pollution prevention, and waste minimization are more likely to be included in new projects/processes, but not if there is a significant increase in associated costs. Publicly owned companies are primarily concerned with turning a profit and any pollution prevention activities will need to contribute to this primary concern. Robert Rhode, BS ChemE / MBA,16 years Industry-production engineering (e.g., inorganic chemicals) I think that most industries are more concerned with making money than preventing pollution. The preventing pollution mindset is fairly new and industries are not really cooperating with the initiative. Because of this, to be competitive, companies are not concerned with the pollution prevention. Laura Blackwell – Co-op at GSK (CBE Senior) Based on my 16 years of manufacturing experience with a top tier chemical company, pollution prevention is consistent with industrial competitiveness only when the pollution prevention activities lower the cost of manufacture or are mandated by regulation. For example, pollution prevention alternatives to the landfilling or incineration of waste will not be used if they cost more than the landfilling or incineration. Robert Rhode, BS ChemE / MBA,16 years Industry-production engineering (e.g., inorganic chemicals)

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Career Experiences of Classmates • I have worked on waste minimization as part of my job. • I have been in a chemical plant for ~12 years. My primary responsibilities include scale-up, formulation and troubleshooting. • Conducted precious metal catalyst research at Pacific Northwest National Laboratory for reverse water gas shift and Sabatier reactions. Project was sponsored by NASA for future manned mission to Mars. • 7 ½ years as a production engineer in the manufacture of inorganic chemicals – calcium chloride, magnesium hydroxide, and bromine • 5 years as a production engineer in pharmaceutical active ingredient manufacturing • 3 ½ years as a production engineer in the manufacture of an insect management product made via fermentation, the last 2 years of which I was responsible for environmental compliance – air, water, waste, and inventory. • I worked at GlaxoSmithKline in the production of Advair. • Currently the job requires to minimize the waste treatment for processes, working on issues to remove metal waste such as Zn and Ti from a process streams. Also working on catalysis for few projects

Career Experiences of Classmates • I currently work in the power industry. Specifically, I have worked on licensing efforts for the development of new nuclear facilities. I have been involved in performing hazards analyses for this licensing effort. • . During my professional career I have done research on SO2 removal and combustion based NOx reduction in coal fired power plants. • . Currently with my senior design group, I am doing research on treating waste water from biodiesel production. I am finding that it is similar to treating municipal wastewater in the methods and trying to find safe ways to dispose of the final waste. • Before freshman year 6 weeks research experience in Dr. Parsons lab working w/ graduate student Joe Spagnola, working with applications of carbon nanotubes. • Worked in Process Development for Diosynth Biotechnology. Did some process modeling. • I did a three semester long rotation co-op at Novozymes, where they manufacture enzymes. I worked in the Recovery, Environmental, and Fermentation departments. I worked with the treatment of PWW and also did testing for toxicity limits

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