露天矿内粉尘聚集机理及影响因素分析

采用计算流体力学等方法，研究了露天矿矿坑几何尺寸特点和逆温现象对露天矿粉尘聚集的影响。研究结果表明：逆温现象阻碍了露天矿矿坑内产生的粉尘向外扩散，是露天矿粉尘污染高发的重要原因；逆温现象的形成机理能较好地解释露天矿粉尘浓度冬春季高而夏秋季低的现象；利用Froude数评价逆温现象对露天矿粉尘扩散的影响，通过敏感性分析可以得出逆温强度是决定露天矿粉尘聚集最主要的影响因素；当逆温现象多发导致矿坑内粉尘扩散不出去时，仅降低某作业环节的粉尘排放量不能避免矿坑粉尘污染的发生。治理露天矿粉尘污染需要从全矿角度出发，结合逆温现象的特点来重新安排矿区整体的降尘抑尘作业，才能控制粉尘浓度的升高。

Analysis on Dust Accumulation Mechanism and Influencing Factors in Open Pit Mine

In this paper, study was carried out on the influence of the geometric characteristics and temperature inversion of the open pit mine upon its dust accumulation by using the method of computational fluid mechanics. The study results showed that the temperature inversion phenomenon hindered the outward diffusion of the dust generated in the open pit mine, and this was an important cause of dust pollution in the open pit mine; the formation mechanism of the temperature inversion can better explain the phenomenon why the dust concentraion in the open pit mine was high in the winter and spring and low in the summer and autumn; the Froude number can be used for evaluating the influence of the temperature inversion on the dust diffusion in the open pit mine, and based on the sensitivity analysis, it can be concluded that the temperature inversion strength was the main influence factor determining the dust diffusion in the open pit mine; when frequent temperature inversion caused the dust in open pit mine to hardly spread out, only reducing dust discharge of a certain operation link can not avoid the mine dust pollution. So the control of dust pollution in the open pit mine needs to proceed from the perspective of the whole mine and rearrange the dust suupression operation according to the temperature inversion characteristics so that the increase of dust concentration can be controlled.