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Show 5 after finishing an experiment. The exhaust gas treating system consists of a secondary combustion furnace to ensure safety during experiments, a gas cooler, and a bag house. 3.2 Pyrolysis experiment In this paper, we report the results of an experiment in which forage pellets were used as simulated refuse. The heating value of the simulated refuse was ad j usted wi th water. The composi ti on and the 1 ower heati ng val ue of the si mul ated refuse are presented in Table 1. Two types of simulated refuse were used in the experiment, with heating value of 9.2 and 14.2 MJ/kg. The primary air ratio was 0.2 to 0.4. It took 3 to 6 hours for the furnace to stabilize. After the furnace had been stabilized, pyrolytic gas and unburned carbon were sampled at the exit of the furnace and analyzed to investigate the fluidized-bed pyrolysis behavior of the simulated refuse. 3.2.1 Relationship between material feed rate and fluidizing air flux Fig.4 shows the relationship between the material feed rate (the charging amount of simulated refuse per unit bed area) and the fluidi zing air flux (the amount of fluidizing air per unit bed area). The operation range for incineration in a conventional fluidi zed-bed incinerator is also given in the figure. Operation with a charging load of up to about 200 kg/m2hr is possible, which i s three to four ti mes the chargi ng 1 oad of a conventional i nci nerator. The above result means that the furnace can be made compact. 3.2.2 Relationship between bed temperature and air ratio Fig.5 shows the relationship between the bed temperature and the air ratio. The relationship is nearly linear and the bed temperature decreases with the decrease in the air ratio. The bed temperature becomes higher as the heating value of the simulated refuse increases. As the result, it was not possible to keep the bed temperature below 600 °C when the heating value was 14.2 MJ/kg. Therefore, for the solid waste with a high heating value it is necessary to recover heat from the fluidi zed-bed. On the other hand, when the heat value of the simulated refuse was 9.2 MJ/kg, it was possible to operate the plant with the desirable bed temperature kept below 600 °C. Hence, it is evident that it |