Mercury and Dioxin Control for Municipal Waste Combustors

Anthony Licata Ucata Energy & Environmental Consultants, Inc. 2150 Central Park Ave. Yonkers, NY 10710-1843 Tel.: 914-779-3451 Fax: 914-779-4234 E-mail: [email protected] Hans-Ulrich Hartenstein L. & C. Steinmiiller GmbH Fabrikstrasse, 1 D-51643 Gummersbach, Germany Tel.: 49-2261-85-2451 Fax: 49-2261-85-2059 E-mail: [email protected] The control of mercury and dioxins from waste-to-energy plants has been of prime concern for facilities around the world. In the U.S., waste-to-energy plants are called Municipal Waste Combustors (MWCs). Control technologies that were developed in Germany in the 1990's became very elaborate and often uses up to five control stages. In the U.S., simpler systems were developed based on the German experience that incorporated good control technologies on a cost-effective basis. Today in Germany, it is common to find disposal fees at MWCs in the range of $150 to $350/ton. This is due to the high cost of air pollution control systems and the lack of competition from landfills. In the U.S., there are many landfills available with disposal fees less than $32/ton that compete with MWCs for waste. Therefore, U.S. MWCs had to implement control technologies that meet world recognized standards for dioxin and mercury emissions at cost competitive bases as well as considering local economics when selecting control technologies. The use of carbon-based technologies is effective in controlling emissions. In addition, a new technology sodium tetra sulfide, is being considered to reduce mercury emissions. This paper discusses the current technologies being used at MWCs in the U.S.