煤矿掘进工作面粉尘延时采样测量方法

Measurement method of dust time-delay sampling in coal mine heading face

为研究煤矿掘进工作面采样时刻对滤膜称重法测量长距离巷道粉尘运移情况的影响,结合有限元分析方法提出延时采样法。首先分析粉尘颗粒沿巷道径向的运动模型,然后估算粉尘在巷道中运移所需的时间,制定粉尘质量浓度测量方案,并在煤矿巷道实地测量。结果表明:延时采样法得到不同时间、不同位置和不同作业工况下相同批次粉尘的运移分布情况,而多点同步采样法的不同起始时间的测试结果稳定性差;分析延时采样法的数据发现“尘汇现象”,其导致弱风巷道粉尘质量浓度的每小时增长速率约为扩散至该区域粉尘质量浓度的10%~15%。分析延时采样法在不同工况下的粉尘质量浓度及其对应的尘汇浓度和测量误差,发现新的非截割尘源位置,并计算产尘浓度,为针对性布置和安装巷道降尘设备提供参考依据。

In order to study the influence of different sampling time nodes on the dust transport in the long-distance alleyway measured by the filter membrane weighing method,a time-delayed sampling method was proposed in combination with the finite element analysis method.The force of dust particles in the flow field was analyzed,and the radial motion model along the roadway was obtained.According to the wind speed distribution of the roadway,the time required for dust to move in the roadway was estimated,a dust concentration measurement plan was formulated and measured in the coal mine roadway was analyzed.The results show that the migration and distribution of the same batch of dust at different times,different locations and different working conditions can be obtained by the time-delay sampling method,while the test results of the multi-point synchronous sampling method at different starting times are unstable.Dust accumulation was found in the data analysis of the time-delay sampling method,which resulted in an hourly growth rate of dust concentration in the weak wind tunnel equal to about 10%-15%of the dust concentration diffused into the area.The dust concentrations and their corresponding dust accumulation concentrations and measurement errors of the time-delayed sampling method under different working conditions are analyzed,new dust source locations are identified,and dust-producing concentrations are calculated to provide a reference basis for the targeted arrangement and installation of dust reduction equipment in the roadway.