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Show Ma.--L-The Burning Properties of Dust from Asphalt-firing in Pulverized Coal Fired Boilers Shinji WATANABE and Takashi KIGA Combustion Engineering Department, Power Plant Division, Ishikawajima-Harima Heavy Industries Co., Ltd. 2-16, Toyosu 3-chome, Koto-ku, Tokyo 135-8733 JAPAN ABSTRUCT Since ashes from heavy oil or asphalt fired boilers contain considerable amount of corrosive materials, they are burned with additional oil in an exclusive incinerator. On the other hand, as they includes much unburned carbon having as much heating value as coal, there is some possibility to use them as fuel. In this study, ashes sampled at the electrostatic precipitator (EP) of an asphalt-fired boiler were examined whether they could be co-fired in the pulverized-coal-fired boilers. From laboratory-scale and pilot-scale test results it was made clear that although the ashes from asphalt firing had as only as a little amount of volatile matter as semianthraci te or anthraci te had, they revealed burn-out properties I ike bi turninous. When they were co-fired wi th pulverized coal by 1% by heat input, a considerable increase in SO, emission was noted, whi I e N0X emission was somewhat decreased compared wi th coal f i ring. From these verifications, it was confirmed that the co-firing of ashes from asphalt f i ring wi th pulverized coal was appl i cable to actual boi lers wi thin the perm i t ted S02 concentration at the inlet of the de-SOx system. INTRODUCTION In recent years, the concern for environmental problems has been increased |