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循环流化床(CFB)锅炉炉膛物料浓度分布直接影响炉膛内的传热特性和锅炉负荷.基于CFB锅炉炉膛内气固两相流动特性,建立了密相区以上区域的物料浓度数学计算模型.以1台1 060t/h CFB锅炉为研究对象,数值计算分析不同煤种、给煤粒度分布、流化风速、分离器效率及床压降对炉膛物料浓度分布的影响,计算分析结果表明,CFB锅炉运行中,针对不同煤质,可以通过优化给煤粒度分布和床压降来调节炉膛上部的物料浓度分布,低挥发分煤种的给煤粒度分布中细颗粒的比例要大一些.分离器性能越好,床质量越好,在相同的流化风速和床压降下,炉膛出口处物料浓度随d5o、d99的减小而增大.“,”The heat transfer characteristics of CFB (circulating fluidized bed) boiler is directly affected by the solid concentration distribution along the height of furnace.Based on the gas-solid dynamics,the calculation model of solid concentration above the dense zone of furnace is established.For a 1060t/h CFB boiler,through calculation,the effects of coal type,the particle size distribution (PSD) of feeding coal,fluidization velocity,cyclone efficiency and bed inventory on solid concentration are discussed.The results show that the solid concentration distribution can be adjusted by optimizing the PSD of feeding coal and the bed inventory.The mass fraction of fine particles in feeding coal should be larger for the coal with low volatile.The better cyclone performance,the higher the bed quality.