针对白芨沟煤矿2621-1工作面煤层赋存条件复杂、原始瓦斯含量高、瓦斯涌出量大、瓦斯灾害严重等问题,在回采前采用顺层走向长钻孔、底板穿层钻孔和本煤层顺层钻孔等相结合的“立体”预抽瓦斯方法,降低煤层原始瓦斯含量;在回采期间采用高位钻孔、联络巷、上隅角插管和大孔径穿层钻孔抽采上覆采空区瓦斯相结合的综合治理措施.上述措施实施后,工作面煤层瓦斯含量大幅下降,工作面回采时绝对瓦斯涌出量最大为79.76 m3/min,回采期间工作面回风瓦斯体积分数最大为0.51％,上隅角瓦斯体积分数最大为0.68％,保证了工作面的安全回采.%Aiming at the problems of the complicated occurrence conditions of the coal seam,the high gas content and emission and the serious gas disasters in 2621-1 working face in Baijigou Coal Mine,a "three dimmentional" gas pre-drainage method was applied to reduce the original gas content of the coal seam before mining with the combination of the gas drainage by long boreholes along seam strike,the gas drainage by floor crossing boreholes and the gas draiange by the boreholes along the the seam being mined;and during mining,comprehensive control measures were used for gas draiange from the over gob by the high -location boreholes,the crossheadings,the plug-in pipes at the upper corner angle and the large-diameter crossing boreholes.After the above measures were taken,the gas content of the coal seam was greatly reduced,the maximum absolute gas emission was 79.76 m3/min in the working face during mining,the maximum gas concentration in return air was 0.51％,and the maximum gas concentration at the upper corner angle was 0.68％ during mining,this thus ensured the safe mining of the working face.
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