A New Resource: The Waste-to-Energy Research and Technology Council. Nickolas J. Themelis, Director, Earth Engineering Center, Columbia University

Transcription

1 11th North American Waste to Energy Conference Copyright C 2003 by ASME NAWTEC A New Resource: The Waste-to-Energy Research and Technology Council Nickolas J. Themelis, Director, Earth Engineering Center, Columbia University Summary Despite the fact that there are over one hundred Waste-to-Energy (WTE) facilities around the country serving tens of millions of people, there are no industrial or government research centers dedicated to solving problems and improving the WfE technology. In recognition of this fact, the Waste-to-Energy Research and Technology (WTER1) Council was formed in May Its mission is to link academic researchers and professionals concerned with integrated waste management and energy recovery from wastes and promote R&D that will advance resource recovery by combustion or gasification. This paper reports on the activities of WTERT in its first year and the research directions that have been identified and initiated. Keywords: WTE, Waste-to-Energy, recycling, resource recovery, dioxins, mercury, greenhouse gas, GHG Introduction The Earth Engineering Center (EEC) is part of the Earth Institute at Columbia University. The Earth Institute (1) is one of the world's leading academic centers for the integrated study of the Earth, its environment, and society. It builds upon excellence in the core sciences - earth, biology, engineering, social, and health - and stresses cross-disciplinary approaches to complex problems. Through research, training, and global partnerships, the Earth Institute aims to mobilize science and technology to advance sustainable development. In addition to EEC, the Institute includes the Lamont-Doherty Earth Observatory, the Goddard Institute for Space Studies, the Center for Environmental Research and Conservation, and the International Research Institute for Climate Prediction. One of the areas of EEC research (2) is the integrated management of wastes (IWM) so as to maximize resource recovery and minimize environmental impacts. New York City has been the working laboratory for various studies that have resulted in several graduate theses and technical papers (3). This work led to two important findings: a) IWM must include both materials recovery, by recycling, and energy recovery, by combustion of the non-recyclable and non-compostable wastes in modem Waste-to-Energy (WTE) plants; and b) there were no U.S. industrial or government research centers dedicated to advancing the WTE technology. The only organization dedicated to helping the WfE industry, the Integrated Wastes Services Association (IWSA, 4), was formed in However, its role does not include R&D although it has an active technology committee that interfaces with state and federal agencies and promotes the exchange of technical information within the industry. On the basis of the above findings, in the spring of 2002, EEC and IWSA agreed to found an organization dedicated to advancing R&D in Waste-to-Energy. It is called the Waste-to-Energy Research and Technology Council (WTERT, 3) and its formation was announced at NA WTEC 10. It is therefore fitting to present at NA WfEC 11 a description of the mission and scope of WfERT and its first year activities. 253

2 Although WfERT is headquartered at Columbia University in the City of New York, one of its objectives is to link all academic research groups that are working on various aspects of WTE technology, as well as other professionals concerned with Integrated Waste Management and the global development of Waste-to-Energy. Mission of WTERT Council WTE technologies are an indispensable tool for the integrated management of municipal solid wastes. Both recycling and WTE reduce the use of virgin materials and energy. Waste-to-energy facilities contribute to the national economies, by providing jobs and generating electricity, and to the environment by conserving non-renewable fossil fuel resources and reducing the environmental impacts of trash disposal. The Waste-to-Energy Research Council (WTER1) brings together engineers and scientists from industry, government, and universities around the world who are interested in increasing the global recovery of materials and energy from used materials. In particular, the WTERT Council focuses on improving the economic and environmental performance of waste-to-energy technologies. Sponsors and organization The founding organizations, EEC and IWSA, provided most of the funding for the July 2002-June 2003 budget of the Council. The following organizations are now cosponsoring WTERT: The Solid Wastes Processing Division of ASME International. The Office for Solid Waste and Emergency Response and the Office of Air and Radiation (Air Quality Planning and Standards) of U.S.E.P.A. The Chlorine Chemistry Council. The Solid Wastes Association of North America. The Municipal Waste Management Association of the U.S. Conference of Mayors. The Green Fund (founded by U.S. Congressman Bill Green). The Council membership is open to engineers and scientists of environmental and waste management organizations, environmental and energy government agencies, and academics engaged in research relevant to the goals of the Council. All professionals concerned with Waste-to-Energy technologies and their effects on energy and the environment, both in the U.S. and abroad, can join the general membership of the Council, be informed of its activities, and contribute to its goals. The executive committee consists of fifteen members that represent the sponsoring organizations. The WTERT Chair is Prof. Nickolas Themelis, Director of the Earth Engineering Center of Columbia University. Ms. Maria Zannes, President of IWSA, is the Vice Chair. The scope of WTERT includes the following activities: 254

3 Collect, analyze and distribute information on major advances in operating practice, results of ongoing R&D, environmental performance of waste-toenergy facilities, and problems of a technical nature encountered by members of the Council. Compile and review crucial operating data that may assist in improving waste-to-energy operations, such as advanced alloys and refractories, new instrumentation and control systems, and novel methods for disposal or beneficial use of ash. Investigate programs and methods to encourage integrated waste management, i.e. the compatibility between strong community recycling programs and pre- and post-combustion resource recovery at Waste-to Energy plants. Research and report on alternate, emerging technologies for resource recovery from solid wastes. Review the results of research work conducted by organizations represented in the Council and report on technological advances in Waste-to-Energy and recycling technologies worldwide. Work with member academic groups and with industry in preparing joint proposals for research to government agencies and other organizations. Current state of the global and the U.S. WTE industries A recent WTERT survey has shown that WTE facilities exist in about thirty five nations with a total population of 2.6 billion. Some of the newest plants are located in Singapore and in China. The predominant technology is mass burning on a moving grate and the foremost technology is by Martin (Munich, Germany; 5) with total installed capacity of about 59 million metric tons. The Von Roll (Zurich, Switzerland; 6) mass burning process follows with 32 million tons worldwide. All other processes have an estimated total capacity of about 40 million tons. Therefore, the total world WTE capacity is estimated at 130 million tons. According to a directive of the European Union, landfilling of combustible materials must be phased out by the year 2005, because of documented concerns regarding emissions from landfilled putrescible materials. However, it is not clear that the large capital investments that will be required to attain this goal are available in the member countries, some of which, like Greece, have no WTE plants at all. The current installed capacity in the European Union and the per capita use ofwte are shown in Table 1 (1). For comparison, the use of WTE amounts to 314 kilograms per capita in Japan, 252 kg in Singapore, and 105 kg per capita in the U.S. Table 1 shows that, in contrast to the U.S., the E.U. makes extensive use of the ability ofwte plants to co-generate thermal and electrical energy. It is noteworthy that one of the newcomers to the global WTE industry is China with seven plants in operation and an annual capacity of 1.6 million metric tons per year. The U.S. WTE industry processes 30 million tons (4), i.e. about 25% of the world WTE capacity. Coincidentally, the U.S. also represents about 25% of the global use of fossil fuels and several other materials. About 60% of the U.S. WTE capacity is concentrated in thirteen states (Table 2, 8). 255

4 Table 1. WfE capacity and generation of thermal and electric energ: in Europe (7) Tons/year Kilograms/ Thermal energy Electric energy Country (in 1999) Capita Gigajoules Gigajoules Austria 450, ,053, ,000 Denmark 2,562,000 10,543,000 3,472,000 France 10,984, ,303,000 2,164,000 Germany 12,853, ,190,000 12,042,000 Great Britain 1,074, ,000 1,895,000 Hungary 352, , ,000 Italy 2,169, ,354,000 2,338,000 Netherlands 4,818, ,130,000 Norway 220,000 1,409,000 27,000 Portugal 322, , ,000 Spain 1,039, ,934,000 Sweden 2,005, ,996,000 4,360,000 Switzerland 1,636, ,698,000 2,311, The word incinerators is being used to describe all types of incinerators. However, this is the wrong appellation for Waste-to-Energy plants that generate electricity and also are subject to very stringent emission standards. For example, in the U.S., there are over 1600 incinerators (medical, sludge, hazardous wastes, etc.) and only 105 WTE plants. Table 2. Major states using WfE in the U.S. (8) State Number of plants Capacity (short tons/day) Florida 13 19,000 New York 10 11,100 Massachusetts 7 9,500 Pennsylvania 6 8,700 Virginia 6 8,300 Connecticut 6 6,500 New Jersey 5 6,300 Minnesota 11 4,000 WfE emissions Until the late eightes, WTE plants were considered to be prime emitters of air contaminants such as volatile metals and dioxins. However, in response to the Maximum Available Control Technology (MACT) regulations imposed by U.S.E.P.A., the WTE industry spent over one billion dollars in retrofitting gas control systems to become one of the lowest emitters amongst high temperature processes. Figure 1 (9) shows the post-mact cumulative emissions of dioxins of the U.S. WTE facilities. The diagonal straight line represents the allowable limit of toxic dioxins (Toxic Equivalent or TEQ grams) using the present E.U. limit of 0.1 nanogram per cubic meter and the cumulative processing rate of MSW (x-axis). It can be seen that the U.S. cumulative emissions are well below the EU standard. The dramatic decrease of dioxin emissions in recent years is also shown in Table 3, which is based on EPA published data, as presented at this conference by WTERT (9). 256

5 POST-MACT PERFORMANCE OF US WTE PLANTS Cumulatlvo Processing Rite, [tonelyelr) Millions Figure 1. Cumulative dioxin emissions (in grams TEQ) of U.S. WTE plants in 2000 (EPA data, 9) Table 3. Sources of dioxin emissions in the U.S., (EPA data, 9) Recorded 1987 Emissions 1995 emissions 2000 sources of dioxins gteq % of U.S. gteq % of U.S. emissions, gramsteq Waste-to-Energy (MSW) Plants % % 15 Backyard refuse % % N.A. barrel burning Medical waste % % incineration Secondary copper % % smelting Cement kilns % % (haz. wastes) Sewage sludge (land % % applied) Residential wood % % burning Coal-fired utilities % % Diesel trucks % 1.10% 35.5 Secondary % % aluminum smeltin Iron ore sintering % % Industrial wood % % burning Bleach pulp &paper % % mills (water) All other U.S % % TOTAL U.S. 13, % 3, % 257

6 Table 3 shows that the WfE industry dioxin emissions have decreased by a factor of 600 between 1987 and Currendy, the U.S. WfE industry emits an estimated total of 15 grams TEQ and is an insignificant source of dioxins. With regard to mercury emissions, a WfERT paper presented at NAWfEC 10 (10) documented a 60-fold decrease in WrE mercury emissions between 1987 and Figure 2 (10) shows that by 1999, WrE mercury emissions were a small fraction of the 1989 emissions. Decrease of U.S. WTE mercury emissions 90 rr == i J6 40 ::J U C!; 30 ::E 0.; 20.s 10 o----l- Figure 2. Decrease in U.S. WTE mercury emissions, (10) Conclusions reached at first WT ERT Council Meeting, November 18-19, 2002 The first meeting of WTERT was held at Columbia University (New York City) and was attended by about eighty members. There were formal presentations by Columbia, Sheffield, Stony Brook, Temple, and Harvard Universities, and by Martin, Covanta and CalRecovery companies. The formal panel discussions addressed four subjects: Improvement of existing WTE operations and next generation processes Beneficial uses of WTE Ash Synergies between recycling and WTE Environmental Impacts of WTE emissions A full description of the proceedings is posted on the WrERT web page (4). The conclusions regarding future research directions were as follows: 1. WTERT should continue as a forum for academic and industrial scientists and engineers concerned with waste management to meet periodically and exchange information about the latest research and technological developments and agree on directions for future research. 2. The recommendation of WTERT for developing a web-based library of technical publications on various aspects of Waste-to-Energy and recycling technologies was accepted and is currendy being implemented. 3. WTERT will pursue with U.S.E.P.A. collaboration in further developing the Decision Support Tool (DS1). In particular, the DST model may be amplified to 258

7 include air emissions of landfills and applied to New York City. WTERT has already compared the carbon dioxide emissions projected by the EPA model with greenhouse gas emissions estimated by Columbia University, Australia and Israel researchers. 4. The mathematical model developed by Columbia University to simulate transport and reaction phenomena in the SEMASS WTE will be amplified to include grate phenomena and will be used to simulate a mass bum combustion chamber. In particular, the effects of air distribution and flue gas recirculation will be examined as well as operating conditions that minimize the formation of NOx. 5. The next contaminant to be investigated is in great detail is NOx. As was done earlier with mercury and dioxins, the WTE emissions will be compared with those of fossil fuel-fired power plants. 6. The WTERT discussions made evident the fact that beneficial uses of bottom ash are of primary importance to the industry. There should be a rigorous comparison of the environmental performance of coal ash and WTE bottom ash and whether there is any reason for WTE ash not to be treated the same as coal ash. This research is of environmental importance because it can also reduce the amount of ash landfilled and thus prolong the life of landfills. Participating academic groups The WTERT Council has already identified a number of academic research groups that are working on various aspects of WTE technology. They are described briefly below. Sheffield University (U.K.) The Sheffield University Waste Incineration Center (SUWIC) is a unique academic center in Europe that concentrates on the use of combustion for resource recovery from solid wastes (11). They are working on several multidisciplinary projects ranging from the development of an advanced control system to novel instrumentation for monitoring turbulence and other conditions in a combustion chamber. The director of SUWIC is Prof. James Swithenbank. Stony Brook University (SUNY) At the Marine Sciences Research Center of the State University of New York at Stony Brook (12), extensive research has been conducted on the beneficial use of coal and municipal solid waste combustion residues since the late 70s. Under the direction of Prof. Frank Roethel, research has focused on the beneficial use of WTE ash as engineered aggregate, artificial concrete reefs, and production of cement blocks. In 1990, the research group used ash-concrete blocks to build a boathouse on the SUNY campus in Long Island. Air quality monitoring and other tests have indicated no adverse environmental impacts. In 1987 and 1988, they built two artificial reefs in Long Island Sound, made of two types of concrete blocks, one containing WTE ash. In contrast to the ash blocks that have maintained their structural integrity, the standard blocks are breaking apart. Also, there have not been any adverse environmental impacts. Prof. Roethel has worked closely with the industry and municipalities in developing uses of WTE ash, e.g., with American Ash Recycling Corp. and Duos Engineering, Inc. in developing an engineered aggregate and with the Bermuda WTE in their efforts to use most of their WTE ash in the construction of artificial reefs. 259

8 Department of Civil and Environmental Engineering, Temple University (Philadelphia) After being associated for several years with EPA as a senior scientist in the hydrogeology and geophysics of remediation projects, in recent years Prof. David Kargbo joined Temple University where he has concentrated on the recovery of Superfund sites. His research group at Temple University has developed permeable reactive barriers (PRB) for groundwater decontamination, and complexation and sequestration methods for aciddrainage of abandoned mines (13). Other research projects are addressed on the environmental consequences of contaminant transport in soils, sediments, and groundwater. Recendy, Prof. Kargbo has focused on the use of coal combustion and WTE ash in the reclamation of contaminated sites. Earth Engineering Center, Columbia University The activities of Columbia's Earth Engineering Center on integrated waste management were mentioned earlier. Prof. Meyer of Civil Engineering has a very active program on the use of recycled glass (glass-concrete, etc., 14) and the beneficial uses of contaminated sediments and WTE ash in concrete blocks and tiles. Prof. Anid (Chair of Chemical Engineering, Manhattan College and Research Associate, EEC; 15) specializes on the containment and mitigation of metal and organic contaminants and will set up at Columbia a laboratory for assessing the leachability of WTE ash used in various applications. Research at Columbia University at the present time addresses the following issues: a) Development of a WTE database as discussed earlier; b) development of mathematical models simulating the combustion phenomena on the Martin grate of a mass-bum WTE and in the combustion chamber above the grate; d) analysis of operating and scientific data regarding the corrosion phenomena in WTE combustion chambers; e) analysis of NOx formation in WTEs and coal-fired plants. Other WTERT initiatives In its summary of the periodic survey of MSW management in the U.S. (16), EPA identifies tonnages recycled and composted but groups the tonnage processed by WTE with landfilling, under disposal. As shown in a WTERT paper published in the NAWTEC 10 proceedings (17), the after-mact WTE air emissions are insignificant in comparison to landfill emissions. Also, a recent paper by Thomeloe et al (18) contained information that confirmed the WTERT analysis of greenhouse gas (GHG) emissions of WTEs and landfills. Table 4 (19) shows that WTE processing of MSW reduces carbon emissions by 0.33 tons of carbon, i.e tons of carbon dioxide/ton MSW. Considering the energy and environmental advantages of WTE, plus the fact that communities that use WTE have invested billions of dollars in these plants, it was reasonable for WTERT to suggest to U.S.E.P.A. in December 2002 that WTE should be shown separately from landfilling. This approach was used by WTERT in a recent article, published in the January 2003 issue of BioCycle (20), and it is illustrated in Table 5 that compares waste generation and disposition in New York, California, and the U.S. 260

9 Tabl e 4. G te e nh ouse G as R e d uct lon b )y com b ustlng mstea d 0 flandfilling (19) Tons of carbon equivalent Source of greenhouse gas per ton MSW reduction Generating electricity by 0.17 combustion of MSW A voiding methane emissions 0.18 at landfill Minus loss in thermal energy of captured methane at landfills Total GHG reduction 0.33 Table 5. Generation and disposition of solid wastes in New York, California and the U.S. in 2000 (20; tonnages in short tons) Population Generated Recycled* Waste-to-Energy Landfilled New York City (NYC) 8,008,000 15,871,990 6,478, ,000 8,842,390 New York (Biocycle, 1) 19,047,000 31,100,000 13,062,000 3,732,000 14,306,000 Los Angeles (LA) 3,694,800 9,110,224 5,359,943 81,860 3,668,421 California (CA) 33,871,000 63,713,793 26,099, ,000 36,954,000 U.S.A. (Biocycle, 1) 281,422, ,000, ,880,000 28,630, ,490,000 *mcludes composllng Conclusions The above report shows that the Waste-to-Energy Research and Technology Council is off to a good start. Now, there is a need to secure sufficient funding, either from government or industry, to support the research work of the academic groups that have already joined in the effort to advance WTE technology and entice other researchers to become involved in WTE research. References 1. Earth Institute at Columbia University, 2. Earth Engineering Center, cui earth. 3. Waste-to-Energy Research and Technology Council, cui wtert 4. Integrated Waste Services Association, 5. Martin technology, 6. Von Roll technology, index.html. 7. ISWA, Energyfrom Waste, State-of the Art Report, 8. Winston Porter, 9. Deriziotis, P. and Themelis, N.J., Dioxins from Waste-to-Energy, Proceedings of NAWTEC 11, ASME International, Tampa FL, April Themelis, N.J. and Gregory, A., Mercury Emissionsfrom High Temperature Sources in Hudson Basin, Proceedings NA WTEC 10, May 2002, Solid Wastes Processing Division, ASME International, p Sheffield University Waste Incineration Center, Marine Sciences Research Center, Stony Brook-SUNY 13. Prof. David Kargbo, Temple University, / astro.temple.edu/ -dka'eboj. 261

10 14. Prof. Christian Meyer, Columbia University, Prof. Nada Anid, l1)lv1v.enginmillg./nanhattan.edu!dlemical (taatltv!anid.html 16. U.S.E.P.A., Municipal Solid Waste in the United States: 2000 Facts and Figures, Office of Solid Wastes and Emergency Response (EPA530-R ), June 2002, Themelis, N.J., Integrated Management a/solid Wastes/or New York City, NA WTEC 10 Proceedings, May 2002, Solid Wastes Processing Division, ASME International, p Thomeloe, S.A., Weitz, KA., Mishtala, Yarkosky. S., and Zannes M., The Impact of Municipal Solid Waste Management on Greenhouse Gas Emissions in the United States A WMA Journal, Vol. 52, p , September Themelis, N. J., Note to Editor, AWMA Journal, January 2003 (in press). 20. Themelis, N. J., Anafyzing Data in State of Garbage in America and EPA Reports, BioCycle January 22, 2003, p