矿井粉尘的分散度及其微观特征分析

Dispersity of Underground Coal Mine Dust and Analysis on Its Microscopic Characteristics

采用滤膜采样、颗粒显微图像分析与统计的方法,测定了矿井不同作业工序条件所产生粉尘的分散度及微观特征。结果显示,在矿井不同的作业工序条件下,所产生粉尘的分散度及显微图片存在显著差异,意味着不同工序所产生粉尘的危害程度有所不同。对于不同的操作工序而言,大多粉尘试样的粒径频率直方图呈现单峰分布的形态,且所产生的小于10μm的颗粒占有较大的比例。综合对比四种作业工序可知,部分工作面打眼和锚杆支护作业所产生的粒径小于2μm的颗粒的比例占到27%。割落煤及掘进过程所产生的粉尘大多分布在2～5μm的粒径范围内,其比例分别为33.7%和42.44%。而通风排放瓦斯过程所导致的逸散粉尘的粒径主要在小于10μm的范围,且粉尘粒径小于5μm的颗粒所占比例差别不太显著。研究结果对于矿井各作业工序粉尘危害的评价及降尘方式的合理选取提供了一定的依据。

The filter membrane sampling, particle microscopic image analysis and statistical methods were used to determine the dispersion and microscopic characteristics of the dust generated during the different mining processes. The resuhs show that there are significant differenees of the dispersion and the microscopic images among the dusts generated from different mining operating processes, which indicate there are different harm. For different mining operating processes, most dust sample frequency histogram of particle size distributions presents single peak distribution and the particles which are smaller than 10 μm occupies a larger proportion. Compared with the results of four operating process, dust generated from the drilling and bolting are always less than 2 μm in diameter, which account for 27%. The diameters of dusts generated from coal cutting and tunneling processes are mostly in the 2 - 5 μm particle size ranges, amt the ratio are of 33.7% and 42.44% respectively. Dusts caused by the ventilation are mainly in the range of less than 10 μm, and the occupations of particle size less than 5 μm seems no significant difference. The research results provide a certain theory basis for dust hazard assessment and the rational selection of dust suppression methods.