The Burning Properties of Dust from Asphalt Firing in Pulverized Coal Fired Boilers

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in all over the world. Therefore the actions for zero emission have become important. Ashes exhausted from thermal power plants are one of the emissions to be reduced and to be utilized effectively. In pulverized coal fired plants, the ashes for the most part collected at the EP have been mainly used as the cement material. Whereas the dusts from heavy oil or asphalt fired boilers are used to be burnt up in incinerators with additional fuel because they contain considerable amount of corrosive materials. The object of this study is to make clear whether the dusts collected at the EP of an asphalt fired boiler (EP dust) can be co-fired in the puIverized-coal-fired boiler. In this study, laboratory-scale and bench-scale experiments were conducted. EXPERIMENTS 1.Chemical and Physical Analysis The properties of EP dust were ultimate by and proximate by analyzed. In addition, the melting point and the micro-pore structure were investigated. 2.Laboratory-scale testing Burning properties of EP dust were investigated by the differential thermal analysis and by combustion testing in a drop tube furnace. Figure 1 shows the schematic diagram of the experimental apparatus for combustion testing. It consisted of a drop tube furnace heated by an electric heater, the system to feed EP dust or pulverize coal, the system supplying gas for combustion, and the gas sampling and analyzing equipments. The drop tube furnace's inside diameter was 42mm and the length was 1200 mm. It was heated by the electric heater of which maximum temperature was 1600°C. The flue gas was sampled by a samp I ing probe which was inserted from the exi t of drop tube furnace. The sampling probe was cooled by water and had an outside diameter of 12mm and inner diameter of 4mm. Table 1 shows the experimental conditions. On the uti I ization of the EP dust, i t wi 11 be straged in a strage bin once.