石棉破碎车间粉尘质量浓度分布的数值模拟及实测

摘要

为改善破碎车间内部粉尘浓度超标的现状,掌握石棉选矿厂破碎车间内粉尘浓度的分布规律,依据气固两相流、气溶胶力学等相关理论,建立粉尘在空气内运动、扩散及沉降方程.以西南某石棉选矿厂破碎车间为研究背景,采用计算机流体力学的离散相模型,运用Fluent软件对石棉破碎车间粉尘质量浓度分布进行数值模拟,并与现场粉尘浓度实测数据比较分析.研究表明:模拟结果和实测数据相吻合;粉尘集中在胶带输送室和破碎机给料口附近,全尘浓度最大为86.24 mg/m3,纤维浓度最高为12.46 f/mL;粉尘浓度随着距破碎机入口的距离增加而逐渐变小;地面呼吸带高度粉尘浓度相对处于较低水平,维持在9~16 mg/m3区间.%In order to improve the situation of dust concentration exceeding and master the distribution laws of dust concentration in the crushing plant of asbestos concentrator, the movement, diffusion and settlement equations of dust in air were established based on the theories of gas-solid two-phase flow and aerosol mechanics.Taking the crushing plant of a asbestos concentrator in southwest as the research background, and adopting the discrete phase model of computational fluid dynamics, Fluent software was used to simulate the mass concentration distribution of dust in the asbestos crushing plant.By comparing with the measurement data of in-situ dust concentration, the si-mulation results were essentially coincident with the measured data.The results showed that the dust concentrated in the belt conveyor and the crusher feed port, the maximum total dust concentration was 86.24 mg/m3, and the maximum fiber concentration was 12.46 f/mL.As the distance away from the entrance of the crusher increased, the dust concentration gradually decreased.The dust concentration was relatively low in the height of ground breathing zone, maintaining in the range of 9-16 mg/m3.