石棉筛分车间粉尘质量浓度分布规律的数值模拟

为了掌握石棉选矿厂筛分车间内部粉尘随时间和空间运移的规律，获取通风除尘优化的参数，以茫崖石棉矿第一选矿厂筛分车间为研究背景，依据气固两相流理论，采用计算机流体力学的离散相(DPM)模型对筛分车间粉尘浓度分布规律数值模拟，并与现场粉尘浓度实测数据比较分析，模拟结果和实测数据相吻合.研究结果表明：筛分设备附近粉尘浓度较高，以筛分设备为中心随着距离增加粉尘浓度降低；捕集边界下粉尘浓度比反弹边界较低，粉尘捕集效果更好；筛分车间进风风速控制在 0.6 m/s左右时，粉尘沉降效果较好；安装抽风集尘罩后，主抽风管风速为 14 m/s时，平均控尘效率达到90%，石棉纤维浓度控制在2.52 f/mL以下.
In order to master the regularities of dust movement with time and space in the screening workshop of asbestos concentrator and obtain the optimized parameters of dust removal by ventilation,screening workshop of No. 1 concentrator in Mangya Asbestos Mine was considered as the research background. Based on the theory of gas-solid two-phase flow,the discrete phase model (DPM) of computational fluid mechanics was used to simulate the dust concentration in screening workshop. By comparing with field measurement of dust concentration distribution,simulation results are essentially coincident with the measured data. The results indicate that the dust concentration near the screening equipment is higher,and the value decreases as the distance from the screening equipment increases. The dust concentration is lower under trap wall condition than the reflect,and the dust trapping effect is better. The dust settling effect is better when the inlet wind speed is about 0.6 m/s. When the exhaust dust cover is installed and the wind speed of main exhaust pipes is maintained at 14 m/s,the average dust-removal efficiency can reach 90%,and the asbestos fiber concentration can be controlled below 2.52 f/mL.