露天煤矿粉尘运移规律及降尘方式研究

Study on dust migration law and dedusting method in open-pit coal mine

通过对大量露天煤矿粉尘数据的采集,梳理了粉尘尘源分类并进行起尘机理分析;以哈尔乌素露天煤矿为研究对象,采用Fluent数值模拟软件对粉尘颗粒运移规律进行分析。研究结果表明:小型颗粒物体积小受重力影响较小,在风力扰动下在采坑内飘散时间较长,大部分可运移至坑外;大型颗粒物受重力影响较大,风力作用下大部分未能运移至坑外,空中飘散一段时间降落至坑内成为二次尘源;3μm和9μm粒径的小颗粒粉尘逸散率具有较强的相关性,20μm粒径的大颗粒粉尘逸散率较低,60μm粒径的大颗粒粉尘基本都在矿坑内部沉降,随粒径的增大,逸散率逐渐降低。针对粉尘分布范围广、降尘难度大的问题,提出空中降尘装置设计方案。

Through a large number of open-pit coal mine dust data acquisition,the article summarizes the classification of dust sources and analyzes the dusting mechanism.Taking Ha'erwusu Open-pit Coal Mine as the research object,the migration law of dust particles was analyzed by Fluent numerical simulation software.The results show that small particle size is less affected by gravity.Under the wind disturbance,the drift time in the pit is long.Most can migrate outside the pit.The large particles are greatly affected by gravity.Most failed to migrate out of the pit under wind.Air scattered for a period of time to fall into the pit as a secondary dust source.The dust emission rates of 3μm and 9μm small particles have a strong correlation.The dust emission rate of large particles at 20μm is low.60μm large particle dust basically settles in the pit.With the increase of particle size,the dissipation rate gradually decreases.Aiming at the problems of wide dust distribution and difficult dustfall,the design scheme of air dustfall device is proposed.