Hauck P.L.,CDM |
LoRe A.M.,Cdm Smith |
19th Annual North American Waste-to-Energy Conference, NAWTEC19 | Year: 2011
When the current generation of U.S. waste-toenergy (WTE) facilities was developed during the 1980s and early 1990s, there were a large number of companies competing to design, build, operate and maintain them under a long term contract. Over the years, almost all of these firms have left the WTE business for a variety of reasons leaving essentially only two U.S. firms actively competing for renewed operating and maintenance (O&M) contracts for publicly owned WTE facilities. This consolidation has significantly reduced the level of competition for public owners who are interested in rebidding their WTE O&M contracts at the end of their initial or extended terms and, as a result, has the potential to increase the cost of service. Consolidation has likewise reduced the level of competition for potential new WTE projects in the U.S. This paper reviews the history of public sector operation of WTE facilities in the U.S., the unique challenges presented by public operation and whether it is time for more public owners to consider this alternative for existing WTE facilities in light of the lack of competition by private operating companies. Perceived risks and impediments to public operation of WTE facilities and suggestions on how to overcome them are presented as well as the benefits and opportunities available to public owners. The keys to a successful public WTE operating venture are also discussed based on the experiences of ecomaine, a consortium of 21 member municipalities in southern Maine that have operated and maintained their own 550 ton per day (tpd) WTE facility for more than 20 years. Public versus private operating practices for European WTE facilities are also explored as well as public ownership and operation of new WTE facilities including those based on. © 2011 by ASME.
Wagner T.P.,University of Southern Maine |
Waste Management | Year: 2015
Worldwide, the generation of municipal solid waste (MSW) is increasing and landfills continue to be the dominant method for managing solid waste. Because of inadequate diversion of reusable and recoverable materials, MSW landfills continue to receive significant quantities of recyclable materials, especially metals. The economic value of landfilled metals is significant, fostering interest worldwide in recovering the landfilled metals through mining. However, economically viable landfill mining for metals has been elusive due to multiple barriers including technological challenges and high costs of processing waste. The objective of this article is to present a case study of an economically successful landfill mining operation specifically to recover metals. The mining operation was at an ashfill, which serves a MSW waste-to-energy facility. Landfill mining operations began in November 2011. Between December 2011 and March 2015, 34,352Mt of ferrous and non-ferrous metals were recovered and shipped for recycling, which consisted of metals >125mm (5.2%), 50-125mm (85.9%), <50mm (3.4%), zorba (4.6%), and mixed products (0.8%). The conservative estimated value of the recovered metal was $7.42 million. Mining also increased the landfill's airspace by 10,194m3 extending the life of the ashfill with an estimated economic value of $267,000. The estimated per-Mt cost for the extraction of metal was $158. This case study demonstrates that ashfills can be profitably mined for metals without financial support from government. Although there are comparatively few ashfills, the results and experience obtained from this case study can help foster further research into the potential recovery of metals from raw, landfilled MSW. © 2015 Elsevier Ltd.
Roche K.H.,Ecomaine |
20th Annual North American Waste-to-Energy Conference, NAWTEC 2012 | Year: 2012
ecomaine manages solid waste for its member communities through an integrated strategy that includes a single sort recycling center, a waste-to-energy (WTE) power plant and a 250 acre landfill for residual ash. The public organization has over 40 member communities in Maine which equates to over 24% of the State's population. Established as a non-profit in the 1970's with a mission to address trash disposal for future generations, a comprehensive waste system has emerged. The method of balefilling municipal solid waste (MSW) was replaced by a state-ofthe- art WTE facility in 1988 and the multiple-sort recycling system was upgraded to a single-sort advanced system in 2007. Roughly 170,000 tons of MSW are processed through the WTE facility each year. This results in an average of 83,000- 105,000 megawatt-hours of electricity generated annually. Since 2005, recycling tonnage has increased 71% from 21,000 to 36,000 tons. The State of Maine established a "Solid Waste Management Hierarchy" in 2007 cascading in disposal preference from Reduce, Reuse, Recycle, Compost, Waste-to-Energy to Landfilling MSW. ecomaine is researching the feasibility of implementing an organics recovery system that would include food waste to further advance the Solid Waste Hierarchy and State's recycling goal of 50%. ecomaine continues to manage its resources through innovation that highlight the resiliency of an integrated waste management system. For example, ecomaine has adapted to periods of waste shortages through strategies of caching MSW during times of higher waste generation and storing that waste until it is needed. ecomaine selects cover material for temporary use that is combustible so that it can efficiently be processed through the WTE facility. When fuel is scarce, the cached material is returned to the WTE as a fuel input. Another example, of matching a waste to a beneficial reuse is ecomaine's ash metals mining project for the recovery of both ferrous metals and valuable nonferrous material from screened ash. ecomaine strives to sustainably treat residual waste streams after enhanced resource recovery re-use and recycling efforts and embrace an integrated waste management system. While challenges face many waste disposal operations such as changing regulations, ecomaine communities believe an integrated system with a good design and forward-looking plant management allow for a robust and effective service, as the ecomaine example shows. Copyright © 2012 by ASME.
Maritato M.C.,Ecomaine |
20th Annual North American Waste-to-Energy Conference, NAWTEC 2012 | Year: 2012
On October 30, 2009 the U.S. Environmental Protection Agency (USEPA) promulgated the Mandatory Reporting of Greenhouse Gases (ghg) across virtually every industry sector in the U.S., including Waste-to-Energy (WTE) plants, emitting over 25,000 metric tons of carbon dioxide (CO2) equivalent emissions per year. In conformance with 40CFR part 98, subpart C stationary fuel combustion sources, WTE plants were required to report 2010 CO2 emissions by September 30, 2011, and annually thereafter by March 31 st. A key element of this process involves the quarterly collection of flue gas samples for characterization of mean biogenic CO2 content. While this rule is in its infancy, it is clear that the Agency intends to regulate CO2 emissions, especially the anthropogenic fraction, across all industry sectors. Currently, ecomaine's sample results for its municipal waste combustor (MWC) contain, on average, 60% biogenic carbon with the remaining 40% fraction characterized by anthropogenic carbon. As ecomaine begins to optimize the removal of organic material through stepped up recycling efforts and the phase-in of large-scale composting operations, it is plausible that the biogenic carbon fraction will diminish over time, leaving a growing fraction of the less desirable anthropogenic carbon. Based on USEPA's 2010 Municipal Solid Waste in the U.S. - 2009 Facts and Figures report (EPA-530R-10-012), the organic fraction of municipal solid waste is approximately 62.5% by weight before recycling. The successful diversion of even 1/2 this material away from ecomaine's MWC could result in a measurable reduction of biogenic carbon, possibly reversing the biogenic:anthropogenic fraction to 40%:60%. This paper will explore strategies, including Life Cycle Analyses of WTE, recycling, and composting operations that the WTE industry can employ to help frame anthropogenic carbon emissions in a better light and stave off future regulatory sanctions as the climate change debate advances to a new level in the years ahead. Copyright © 2012 by ASME.