三产品旋流分级筛脱泥性能研究

Desliming performance of the three-product cyclone classification screen

针对近年来选煤过程中亟待解决的高灰细泥影响分选效果难题,进行了三产品旋流分级筛脱泥性能研究.论文以旋流两相流和颗粒透筛理论为基础,首先对颗粒运动进行分析,得出离心沉降相对末速、最大分级粒度及粒度分布规律;然后对脱泥性能影响较大的溢流管进行试验,得到当溢流管插入深度为475mm（柱-锥分界面）、最小溢流管内径为柱段内径的0.075~0.15倍时,细泥（-45μm）脱除率较高为90%;最后对比平衡轨道理论分级模型与实际分级粒度,确定内旋流波瓦罗夫公式为适合该设备脱泥特性研究的理论分级模型.

The desliming performance of three-product cyclone classification screen was studied in this paper to improve the separation efficiency of fine slime with high ash content.Firstly,the particle motion was analyzed based on the two-phase flow and particle screening theories,and the centrifugal settling relative terminal velocities,maximum separation size and size distribution patterns were concluded.Then,the overflow pipe affecting the desliming performance most was tested.When the insertion depth of column-cone interface is 475 mm and the inner diameter of minimum overflow pipe is 0.075—0.15 times of that of column section,the removal rate of fine slime can reach 90%.Finally,by the comparison between the equilibrium orbit theory and actual separation size,theПoBapoB Formula in internal swirling flow is determined as the theoretical grading model that best fits the desliming performance of this equipment.