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Show 1 Fluidized-bed Pyrolysis and Swirl-flow Melting System for Municipal Solid Waste Toshiya Tada, Tadashi Yaso, Mamoru Suyari, Hiroaki Kawabata, Tomio Suzuki Kobe Steel, LTD. ABSTRACT A new municipal solid waste incineration system which includes a directly connected fluidi zed-bed pyrolysis furnace and a swirl-flow melting process has been developed. In this system, inflammable materials formed in a pyrolysis furnace with partial combustion are utilized for melting the waste ash in a melting furnace. To develop this new process, the pyrolysis characteristics of waste in the fluidized-bed furnace were studied experimentally using the simulated waste. The following results were obtained. 1. The operating conditions of fluidized-bed pyrolysis 2. The effects of lower heating values of waste and air ratio on bed temperature 3. The effects of bed temperature on pyrolysis gas components 4. The oxidation of metals in the pyrolysis process Also the results of operation of a facility of about 2 tons/day capacity are presented. The facility has already operated more than 600 hours. Through the experimental results and operating experience the usefulness of this system was confirmed. 1. Introduction In Japan, municipal solid waste is mainly processed by incineration, and the discharged ash is disposed of at landfill sites. Incineration offers stable and sanitary processing for large quantities, and that enables a large reduction in ultimate disposal volume. However, the annual volume of municipal solid waste, about 50 million tons/year, is increasing and the capacity of the landfill sites is decreasing year by year. Further reduction of the volume of discharged ash is required. In addition, secondary pollution by the harmful components of heavy metals leached from landfilling ashes is feared, and so the inactivation and stabilization of ash has become an important issue. |