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[greenyes] White Paper # 8 Biological, Chemical and Thermal Technologies

Apologies for Cross-Postings

GRC is circulating portions of a White Paper for your review and comment and welcomes your suggestions. Please reply to this listserve with comments.

August 26 ? 27, 2004 ? Global Recycling Council: International Dialog on Proper Discard Management in the New Millennium, San Francisco, CA.

White Paper # 8

Biological, Chemical and Thermal Technologies

By Gary Liss, Gary Liss Associates, Loomis, CA,

Although the diversion rate in California is estimated to be approximately 47%, over 37 million tons of material is still disposed of in landfills. Of the materials landfilled, 79% of the material is organic (biomass and plastic carbonaceous material). Some are advocating that these materials that are currently still being landfilled should be processed to produce energy. Technologies that are being proposed include biological, chemical and thermal technologies. Materials that are proposed to be processed with these technologies are primarily the organic materials that are now being landfilled. These include paper, cardboard, plastic, discarded food, and yard trimmings.

Biological processes are used to process higher moisture materials. Source separated organic materials (e.g., yard trimmings and discarded food) provide the highest quality and most marketable end-products from such processes. Some biological systems, such as anaerobic digestion, are being used primarily as pollution control devices; after all other Zero Waste techniques are employed.[i][ii] Chemical processes are being proposed to process difficult to recycle materials, such as plastics.

Thermal processes are being proposed with many different names and configurations, including: combustion (or incineration), waste-to-energy, pyrolysis, gasification, plasma arc, and catalytic cracking. Whatever they are called, they all are designed to heat discarded materials until they are either destroyed, or converted into liquids, gases, char and ash. Most of these systems operate at high temperatures (over 750 to 3,000 degrees Fahrenheit). Plasma arc systems operate at 9,000 ? 27,000 degrees Fahrenheit.

Pyrolysis systems are designed to heat materials to high temperatures without adding oxygen, as in an oven. Gasification systems often involve the addition of air, oxygen, hydrogen, or some combination of these reactants. The composition of the products of these systems can be changed by the temperature, the pressure, the speed of the process, and the rate of heat transfer.[iii] Pyrolysis systems produce both gas and liquid products, with lower temperatures producing more liquid products and higher temperatures producing more gases. The products from these systems are usually burned to produce energy. Some technologies directly convert resources to electricity while others create liquid or gaseous fuels.

The European Union Parliament's Directive on Incineration of Waste defines pyrolysis and gasification as incineration:
?[I]ncineration plant' means any stationary or mobile technical unit and equipment dedicated to the thermal treatment of wastes with or without recovery of the combustion heat generated. This includes the incineration by oxidation of waste as well as other thermal treatment processes such as pyrolysis, gasification or plasma processes in so far as the substances resulting from the treatment are subsequently incinerated.?[iv]
The USEPA considers gasification to be combustion under EPA?s medical waste incinerator rule.[v]

Plasma arc and radio frequency (microwave) heating converts heat from electricity to gasify, pyrolyze, or combust the materials, depending on the amount of oxygen or hydrogen fed into the reactor. Catalytic cracking refers to the addition of catalysts to wastes such as plastics in a pyrolysis system to produce liquid fuels (such as gasoline). However, the catalysts may be deactivated by chlorine present in PVC plastics.

Depending on the composition of the waste and operating conditions, incineration, pyrolysis and gasification release poisonous substances like dioxins and furans, toxic metals are volatilized (e.g., mercury, cadmium, chromium, beryllium, vanadium, zinc, manganese, nickel, selenium and tin), and particulate matter, other halogenated organic compounds, carbon monoxide, hydrogen chloride, sulfur dioxide, arsenic, are also released to the air. Toxins such as dioxins and furans are dangerous at extremely minute levels. Since failsafe systems have not been demonstrated to control migration of these toxins to the environment, it is better to apply the Precautionary Principle to preclude high-temperature technologies, create systems that maximize the highest and best use of discarded materials, and require safe waste disposal alternatives for any remaining materials. Ironically, maximizing energy recovery is technologically incompatible with reducing dioxin emissions. One alarming new trend is the increase in projects to use incinerator ash and disperse it throughout the environment despite toxic contaminants in the char or ash residues.

The key to determining when energy generation from discards may be consistent with Zero Waste lies with whether feedstocks are source-separated and at what temperatures the technologies operate. Technologies of the 'Carbohydrate Economy' espoused by the Institute for Local Self-Reliance and others are consistent with the goal of Zero Waste. For example, making bio-diesel fuel from source-separated organic materials could help meet air pollution control goals for transportation.

Thermal technologies using mixed garbage feedstocks or high temperatures destroy resources, are incompatible with Zero Waste systems and are threats to human health and the environment. Reusing, recycling or composting the same materials burned in an incinerator can save about 3-5 times more energy.[vi] When you burn something you have to replace it starting with virgin materials; this is where the energy is used and the major contribution to global warming is created. Thus, even if thermal technologies could be operated safely, they would not be sensible. It simply does not make sense to spend so much money destroying resources we should be sharing with the future. [vii]

For every ton of material destroyed by thermal technologies, about 71 tons of manufacturing, mining, agriculture, oil and gas exploration, coal combustion, and other discards are produced.[viii] There are significant upstream benefits of avoiding wastes from mining, manufacturing and distribution of products, including energy conservation and reduced greenhouse gas emissions benefits of waste prevention and recycling. Reduced waste generation to 1990 levels and increased recycling to 35% would reduce greenhouse gases by 11.4 million metric tons of carbon equivalent (MTCE), equal to taking nearly 7 million cars off the road for one year.[ix] By cutting the amount of materials discarded by just 5%, we could reduce greenhouse gas emissions by another 10.2 million MTCE.[x]

As a result, no public subsidies should be provided for any form of thermal technologies. In particular, communities should not enter into any ?put-or-pay? contracts that may be requested to support thermal technologies. These contracts may deter competition, damage reuse, recycling and composting businesses, and discourage waste reduction. In addition, federal, state and local governments should not include thermal technologies in any programs designed to promote and expand renewable energy sources.

The terms ?waste,? ?waste resources,? ?waste incineration,? ?pyrolysis,? and ?gasification? should be excluded from qualifying as renewable or sources of renewable energy, fuel, or power in renewable portfolio standards, renewable energy solicitations, renewable energy grant/loan programs, green or clean power programs, biomass energy programs, and other related programs, regulations, legislation, and policies. The term ?municipal solid waste? should be excluded from the definition of "biomass" in renewable energy standards, procurement policies, and other related programs, regulations, legislation, and policies.

Professionals dedicated to achieving a sustainable economy based on the principle of Zero Waste should encourage a combination of community responsibility and industrial responsibility towards the way materials pass through our society. Where ?waste? is currently produced, the emphasis should be placed on better industrial design to eliminate its production, wherever humanly possible, rather than finding a technology to make the material disappear. Thermal technologies costs cities and counties more and provides fewer jobs than comprehensive reuse, recycling and composting, and deters the development of local recycling-based businesses.

Environmental impact reports should compare the impacts of biological, chemical and thermal technologies to expanded reuse, recycling and composting alternatives, and approaches that eliminate waste.

A huge capital and political investment in biological and chemical technologies could distract decision makers in government and industry from the primary task of designing packaging and products which can be reused, recycled and composted.

Although some biological and chemical technologies may help us to develop the Carbohydrate Economy that eliminates our society?s reliance on scarce oil and gas supplies, these technologies must be designed first and foremost to protect the public?s health and safety and the environment, as well as ensuring that we remain focused on truly sustainable practices.

For more information:

· ?Resources Up In Flames, The Economic Pitfalls of Incineration versus a Zero Waste Approach in the Global South,? prepared by the Institute for Local Self-Reliance (ILSR) for Global Alliance for Incinerator Alternatives (GAIA),

· Neil Tangri, GAIA, ?Waste Incineration: A Dying Technology,? July, 2003,

· Greenpeace, ?Incineration and Human Health,? 2001,

· USEPA, ?Draft Summary of the Dioxin Reassessment,? 1994,

· Center for Health, Environment and Justice, ?America?s Choice: Children?s Health or Corporate Profit: The American People?s Dioxin Report,?

· Blue Ridge Environmental Defense League (BREDL), ?Pyrolysis and Thermal Gasification of Municipal Solid Waste,?

· Blue Ridge Environmental Defense League (BREDL), ?Waste Gasification: Impacts on Public Health,?

· Blue Ridge Environmental Defense League (BREDL), ?Incineration and Gasification: A Toxic Comparison,?

· ?Incineration Repackaged? by Stephen Lester (CHEJ), repackaged.html

· McNeill, I.C., Memetea, L., Mohammed, M.H., Fernandes, A.R., Ambidge, P. 1998. ?Polychlorinated dibenzodioxins and dibenzofurans in PVC pyrolysis. Polymer Degradation and Stability,? 62:145-155.


[i] In Halifax, Nova Scotia, all solid waste that has not been reduced, reused, recycled or composted before it reaches the landfill is processed in an anaerobic digestion process with concrete bunkers. This approach was taken to ensure that all organics that could produce gases in the landfill are digested at this stage in a controlled environment, and to ensure that all toxics are leached out of the waste before being buried.
[ii] Source: non-published studies performed for the CA Integrated Waste Management Board, 2004. For more info, contact Fernando Berton, 916-341-6590 or fberton@no.address
[iii] Ibid, Berton.
[v] ?Pyrolysis and Gasification Presentation? to NCRA Recycling Update 2004, by Jorge Emmanuel, PhD, February 4, 2004, San Francisco.
[vi] Personal communication from Dr. Paul Connett, Professor of Chemistry, St. Lawrence University, Canton, NY 13617, 315-379-9200, ggvideo@no.address
[vii] Ibid, Connett.
[viii] Brenda Platt and Neil Seldman, Institute for Local Self-Reliance, ?Wasting and Recycling in the United States 2000,? prepared for the GrassRoots Recycling Network, page 13,
[ix] <> Ibid, Platt and Seldman, page 25.
[x]<> Ibid, Platt and Seldman, page 25.

Gary Liss
Fax: 916-652-0485

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