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Show 2 The melting and solidification of ash is considered to be an effective technique that will meet the requirements mentioned above. In this process, ash is melted by heating to a temperature higher than the melting point, cooled to solidify, and recovered as slag. Some refuse disposal plants which have both an i nci nerati on process and a mel ti ng-sol i di f i cation process are operati ng, but a considerable amount of valuable energy in municipal solid waste is lost in this process, although some is recovered by boilers and so on. In recent years, systems which consists of both a pyrolysis process to gasify wastes and a melting process have attracted attention as a "next generation" waste processing method. As a new municipal solid waste incineration system, we have also proposed a fluidi zed-bed pyrolysis and swirl-flow mel ting process, in which our own incineration technique (fluidized-bed furnace) and melting technique (swirl-flow melting furnace) are used very efficiently. The present paper gives an outline of the process and of the pyrolysis characteristics of solid waste in a fluidi zed-bed furnace, which is important data in establishing the process. We also report on the results of operation of a pilot plant of about 2 tons/day capacity, which directly connects a fluidized-bed furnace and a swirl-flow melting furnace. 2. Fluidized-bed pyrolysis and swirl-flow melting process 2.1 System flow Fig.1 shows the process flow of the fluidi zed-bed pyrolysis and swirl-flow melting system we have proposed. This process has the following features: O It consists of field-proven techniques. O The process configuration is simple. In this process, using the fluidized-bed furnace which is well-proven in the field of municipal solid waste incineration, partial combustion is carried out at an air ratio of 0.2 to 0.4 and low temperature pyrolysis with the fluidi zed-bed temperature kept at 500 to 600°C is performed. The dust and pyrolytic gas generated in the pyrolysis furnace are led into the swirl-flow melting furnace, which has often been used for melting the incineration ash of sewage sludge, and the carbon in the pyrolytic gas and dust are burnt there at a total air ratio of about 1.3. In the melting furnace, high temperature combustion at about 1300°C is achieved, the ash is melted and separated as slag, |