摘要：为了降低燃煤电厂的磨机功耗，减少锅炉燃烧后的污染排放，通过分析磨煤机分离器返料的粒度和密度分布，对电厂采样物料进行稀 相流化床分选去除黄铁矿等矿物质的实验研究，并对物料分选过程进 行数值模拟。结果表明，粒径小于 0.500 mm 的分离器返料在流化床中 具有较小的起始流化速度 1.62 cm/s，流化床各层的密度和粒度具有很好的稳定性；物料中的黄铁矿等矿物质得到分离，上层和底层物料灰分 质量分数分别为 33.34%、73.42%，硫分质量分数分别为 1.12%、8.96%，底层物中硫主要以黄铁矿的形式存在；气-固两相流稀相分选床的流场 形态及颗粒运动数值模拟验证了实验结论。 

关键词：磨煤机；分离器返料；稀相流化床；黄铁矿；数值模拟

Abstract：To reduce the energy consumption and subsequent air pollution of coal-fired power station，based on the analysis on size and density distribution of particles from the recirculating load of the classifier of pulverizer， the separation experiment on sampling material from a power plant with a dilute phase fluidized bed to remove pyrite and other minerals and numerical simulation on the separation process were done. The results show that the minimum initial fluidization velocity of classifier recirculating load with particle sizes below 0.500 mm fluidized bed is 1.62 cm/s. The density and particle size of each layer in fluidized bed have good stability. Pyrite and other minerals in the material are separated. Ash of the upper and bottom layer material account are 33.34% and 73.42% ，sulfur content occupy 1.12% and 8.96% respectively. Scanning electron microscopy and spectroscopy tests show that sulfur in the bottom material exist in the form of pyrite. Numerical simulation on the flow field form of the dilute phase separation bed with gas-solid two phase and particle motion verifies the experimental conclusions. 

Keywords：pulverizer；recirculating load of classifier；dilute phase fluidized bed；pyrite；numerical simulation