INVESTIGATION ON SO2 EMISSION FROM 410T/H CFB BOILER BURNING PETROLEUM COKE AND COAL
Due to its good fuel flexibility and low pollutant emission, circulating fluidized bed (CFB) combustion technology is considered to be one of the clean combustion technologies, and it becomes possible to use high sulfur petroleum coke as an alternative fuel in CFB. The combustion characteristics of a 410t/h CFB boiler burning three kinds of fuels, in terms of bituminous coal(BC), 70％ bituminous coal+30％ petroleum coke(PC) and 50％ anthracite(AN)+50％ petroleum coke, were studied. Effects of operation parameters, including bed temperature, Ca/S molar ratio, excess air coefficient, fly ash recirculation rate and limestone microstructure on SO2 emission were verified. Test results indicate that all the three kinds of fuels could be burned adequately in the boiler, and the bed temperature distribution is uniform. For different fuels, SO2 emission is correspondingly related to sulfur content in it at the same operation parameters. With increasing bed temperature, SO2 concentration in the flue gas reduces first and then increases. There is an optimal desulfurization temperature. For burning bituminous coal only or 70％ bituminous coal +30％ petroleum coke, the optimal desulfurization temperature is about 850℃, while it is about 850-870℃ for burning 50％ anthracite +50％ petroleum coke, because of the different sulfur content in the fuel. The SO2 concentration decreases with the increase in Ca/S ratio, excess air coefficient and fly ash recirculation rate. Results also show that the microstructures of limestones such as specific surface area and specific pore volume have distinct impact on their SO2 retention, and bigger specific surface area and higher specific pore volume can improve their SO2 capture activities to a certain extent. The optimal temperature, Ca/S ratio and excess air coefficient for different fuels are recommended for industrial application. All the experimental results are beneficial to providing the database for the design and operation of the CFB boiler.
Circulating fluidized bed Petroleum coke SO2 emission Fly ash recirculation Microstructure
Lunbo DUAN Xiaoping CHEN Yingjie LI Cai LIANG Qingzhao LI Changsui ZHAO
Key Laboratory of Clean Coal Power Generation and Combustion Technology of Ministry of Education, Southeast University, Nanjing 210096, Jiangsu, China
国际会议
第六届煤燃烧国际会议(The 6th International Symposium on Coal Combustion)
武汉
英文
434-440
2007-12-01（万方平台首次上网日期，不代表论文的发表时间）