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Show 7 Fig.8 shows an example of the measurement of the exhaust gas composition at a pyrolysis and melting test using the simulated refuse. The temperature in the melting furnace is 1300 to 1400 °C. Because the total air ratio is about 1.3, the oxygen concentration at the exit of the melting furnace is 4 to 5 %. The concentration of nitrogen oxide is 100 to 150 ppm, which is the equivalent discharge to that of the incinerator. Therefore, it is desirable to install a N0X removal reactor in the actual equipment. The concentration of discharged CO is under 10 ppm on the average, a relatively low value, because of high temperature combustion and good mixing. In the actual equipment, combustion will be further stabilized due to the scale up effect. The leaching data for slag discharged from the melting furnace are shown in Table 2. All of the toxic heavy metals regulated in Japan are leached well below the specified limits. Thus, the slag obtained from this system may be used as a material for roadbeds, for example. 4. Conclusion Kobe Steel has proposed the fl ui di zed-bed pyrolysis and swirl-flow melting process as a future municipal solid waste incineration system. In this study, an important part of this process, fluidized-bed pyrolysis behavior, was experimentally studied and the conditions for designing and operating the pyrolysis furnace were clarified. In addition, by operating the pyrolysis furnace coupled with a melting furnace, the data for exhaust gas and discharged slag were obtained. It was also found that this system is very effective in recovering resources. As a result, it was confirmed that the fluidized-bed pyrolysis and swirl-flow melting process proposed by Kobe Steel can be achieved. We are going to carry out a long-term experiment using a demonstration plant, which has a capacity of 30 tons/day, on actual municipal solid waste from October,1998. References 1) Yaso,T., Minoura,T., Higashi,Y., Tada,T. and Kawabata,H., Proceedings of The 2nd SCEJ Symposium on Fluidization, p156-161(1996) 2) Yaso,T., Minoura,T., Higashi,Y. and Tada,T., Proceedings of JFRC Japan Flame Days '97,(1997) |