平山煤矿采空区高位钻孔瓦斯抽放数值模拟

Numerical Simulation on Goaf Gas Drainage of High-level Borehole in Pingshan Coal Mine

针对平山煤矿首采煤层11011工作面采空区瓦斯浓度较高和上隅角瓦斯超限问题,提出高位钻孔瓦斯抽放的治理方案。基于采空区高位钻孔参数布置方程,计算分析了11011工作面采空区瓦斯抽放问题,并通过Fluent软件模拟了高位钻孔下采空区瓦斯浓度分布,直观展现了瓦斯浓度的分布变化。把高位钻孔布置在双"U"的外"U"中,离回风巷平距20 m处开孔,开孔高度为4 m。现场实验数据显示,该抽放技术使得上隅角瓦斯浓度低于0.5%。

In order to solve the problem of high gas concentration in goaf and gas exceeding the limit in the upper comer at11011 working face of 3~ coal seam in Pingshan Coal Mine, the goaf gas drainage of high-level borehole was proposed. On thebasis of the design parameter equations of high-level borehole in goaf, this paper analyzed the gas drainage problem of goaf at 11011 working face of 3# coal seam in Pingshan Coal Mine. Then, we used the Fluent to simulate the gas concentration distribution ingoal of high-level borehole, which displayed the distribution change of gas concentration. The high-level borehole was arranged inthe outside ＂U＂ of the double ＂U＂, the horizontal distance between the hole position and return airway was 20 m and the height ofthe hole was 4 m. The on-site experimental data showed that gas concentration of upper comer was less than 0.5%.