大直径定向高位长钻孔瓦斯抽采数值模拟及治理效果

Numerical simulation and treatment effect of gas drainage by large diameter directional high-level long boreholes

为解决山西华阳集团新能股份有限公司二矿1031工作面上隅角瓦斯超限问题,基于COMSOL的煤层覆岩模型,针对不同孔径下的抽采负压进行模拟分析,选取直径为153 mm的钻孔,抽采负压为20 kPa进行现场测试,结果表明,抽采后的上隅角瓦斯浓度平均为0.48%,比抽采前期降低了0.66%,说明大直径定向高位长钻孔能帮助1031工作面处理瓦斯浓度过高的问题,减少生产过程中会出现的安全隐患。

In order to solve the problem of gas overrun in the upper corner of 1031 working face of Shanxi Huayang Group Xinneng Co.,Ltd.No.2 Mine,based on the coal seam overburden model of COMSOL,the negative pressure of extraction under different apertures is simulated and analyzed.The borehole with a diameter of 153 mm is selected,and the negative pressure of extraction is 20 kPa for field test.The results show that the average gas concentration in the upper corner after extraction is 0.48%,which is 0.66%lower than that in the early stage of extraction.It shows that the large-diameter directional high-level long borehole can help 1031 working face to deal with the problem of high gas concentration and reduce the potential safety hazards in the production process.