以青东煤矿首采726工作面作为上保护层,探讨了上保护层瓦斯来源:本煤层瓦斯、回采阶段下邻近层8号煤层涌出的瓦斯。分源预测法计算表明,8号煤层涌出的瓦斯为726工作面的主要瓦斯涌出源,由于保护层开采结合卸压瓦斯抽采是煤矿瓦斯治理的主要技术手段,提出了本煤层回采期间顶板巷条带网格穿层钻孔抽采、顶板巷分段封闭抽采、回风巷下向穿层钻孔抽采、顺层钻孔抽采、采空区埋管抽采等瓦斯治理方案。采取上述瓦斯综合治理措施后,平均瓦斯抽采流量15.96 m3/min,工作面瓦斯抽采量达到729.44万m3,瓦斯抽采率达到75%以上,杜绝了工作面上隅角瓦斯超限。

Taking No.726 coal mining face of Qingdong Mine as the upper portective seam, the paper discussed the gas sources of the upper portective seam and t he gas sources were the mining seam gas and the gas emission from No.8 seam, the neighbor seam under the mining seam level.The calculation of the individual sourc e prediction showed that the gas from No.8 seam was the main gas emission source of No.726 coal mining face.The protective seam mining in combination with the pre ssure released gas drainage was the main technical means of the mine gas control.The gas drainage with band steel mesh through bed boreholes in the roof gateway d uring the mining period of the mining seam, sectional sealing gas drainage in the roof gateway, through bed borehole gas drainage in the downward direction of the air「 eturning gateway, in and along seam borehole gas drainage, pipeline buried in goaf gas drainage, and other gas control plan were provided . After using the comprehensi ve gas control measures, the average gas drainage flow was 15.96 m3/min in average, the gas drainage value of the coal mining face was 7.294 4 million m3, the gas d rainage rate was over 75% and the gas content over the limit at the upper corner of the coal mining face was eliminated.