循环流化床中石油焦与煤混合燃烧SO_2排放特性研究

Invistigation on SO_2 Emission of Petroleum Coke Combustion Blending with Coal in CFB

在一座0.5MWt循环流化床热态试验装置上进行了石油焦与煤混合燃烧试验,研究了烟气中SO2的排放特性.对于石油焦与煤不同燃料配比,不同锅炉运行参数,如过量空气系数、床温、一次风率、Ca/S比等对烟气中SO2排放浓度的影响规律进行了研究.试验表明:对不同配比的燃料,随过量空气系数和一次风率的增大,SO2排放浓度降低;对于床温有一最佳温度,其SO2排放浓度最低;随Ca/S增大,SO2排放浓度降低.

Petroleum coke is a byproduct of the residua from the crude refining process. It is considered as a cleaner and more effective way to burn the petroleum coke blended with coal in a circulating fluidized bed combustor. In this paper, systematic combustion experiments of mixed fuels with different ratios of petroleum coke over coal are conducted on a 0.5 MW_t pilot-scale CFB(circulating fluidized bed) facility. The effects of various parameters, in terms of the ratio of petroleum coke to coal, the excess air coefficient, the bed temperature, the primary air fraction, the Ca/S ratio on the SO_2 emission in the flue gas are revealed in this paper. It indicates from the experiments that with the increase of primary air fraction, the excess air coefficient and the Ca/S ratio,the SO_2 concentration in flue gas decreases for all fuel mixtures. There is an optimal temperature at which the SO_2 concentration is the lowest.