低瓦斯矿井综采工作面上隅角瓦斯超限机理及治理技术

Mechanism and Control Technology of Gas Overrun in Upper Corner of Fully Mechanized Mining Face in Low Gas Mine

店坪煤矿203工作面回采期间,上隅角多次出现瓦斯超限现象,治理难度大,严重制约着工作面安全高效回采。分别从地质构造、围岩裂隙情况、通风方式、邻近采空区影响等几方面,分析了上隅角瓦斯超限原因,并根据回采现状,优化工作面通风方式;采用Y型通风系统,提出了“高位瓦斯钻孔+采空区大直径钻孔负压抽采+顺层钻孔抽采”联合瓦斯抽采技术。通过现场实际应用效果来看,上隅角瓦斯浓度降低至0.4%,回风流中瓦斯浓度降低至0.9%,落煤点瓦斯浓度降低至0.6%,取得了显著应用成效。

During the mining of 203 working face in Dianping Coal Mine,gas overrun occurred many times in the upper corner,which was difficult to control and seriously restricted the safe and efficient mining of working face.The causes of gas overrun in the upper corner are analyzed from the aspects of geological structure,fracture development of surrounding rock,ventilation mode and influence of adjacent goaf.According to the current situation of mining,the ventilation mode of working face is optimized.The Y-type ventilation system is adopted,and the combined gas drainage technology of'high gas drilling+large diameter drilling negative pressure drainage in goaf+bedding drilling drainage'is proposed.According to the practical application effect,the gas concentration in the upper corner is reduced to 0.4%,the gas concentration in the return air flow is reduced to 0.9%,and the gas concentration in the coal falling point is reduced to 0.6%,which has achieved remarkable application results.