对新大地煤矿15101综放工作面利用工作面超前支承压力作用提高低透气性煤层瓦斯抽采效果进行了现场实测研究,结果表明:本煤层瓦斯抽采效果受工作面超前支承压力的影响十分明显,根据本煤层瓦斯抽采钻孔所处位置,其抽采效果可以大致分为4个时期:原始抽采期(工作面前方50 m以外)、抽采减弱期(工作面前方50-20 m)、抽采增长期(工作面前方20-7.38 m)及抽采衰减期(工作面前方7.38 m以内)。其中,抽采增长期和抽采衰减期钻孔瓦斯抽采纯量分别为原始抽采期的7.03倍和6.19倍,是本煤层瓦斯卸压抽采的最佳时期,该时期内钻孔抽采量占本煤层瓦斯抽采总量的57.83%。
Based on field measurement,the effects of advanced abutment pressure on high-efficient gas extraction from low permeability working seam are researched at #15101 top coal caving longwall face of Xindadi Coal Mine.The results show that the influence of advanced abutment pressure on gas extraction effects in coal seam currently mined is very obvious.Gas extraction effects are roughly divided into four sections in line with the positions of gas extraction boreholes,i.e.primitive section(50m in advance of the working face and beyond),extraction decreasing section(50m~20m in advance of the working face),extraction increasing section(20m~7.38m in advance of the working face) and extraction attenuation section(within 7.38m in advance of the working face).Single hole average gas extraction quantity in the extraction increasing section and attenuation section is 7.03 and 6.19 times that of the primitive section.So,extraction increasing section and attenuation section are the best sections for gas extraction in the coal seam currently mined,for gas extraction quantity there accounts for 57.83% of the total gas extracted from the coal seam currently mined.