School of Safety and Emergency Management Engineering, Taiyuan University of Science and Technology,
Taiyuan 030024 , China

近距离煤层群赋存分布较为广泛，开采条件下工作面回采期间瓦斯涌出来源多，瓦斯运移规律较单一，煤层开采更为复杂，亟需采取有针对性的技术措施。针对近距离突出危险煤层群开采时面临的“一层采动，多层卸压”和瓦斯治理困难等问题，本文以屯兰煤矿2号煤层为工程背景，利用FLAC3D软件模拟了工作面回采时的围岩应力场、位移场和塑性区分布情况，并以此为依据确立了上邻近层定向长钻孔的施工方案。研究成果表明，O 形圈的宽度随煤层开挖的增加而增大。当屯兰2号煤层工作面开采进尺达到30 m时，O形圈范围已达15 m。卸压瓦斯大量解吸，且垮落带和裂隙带沟通了上覆煤层，并对上邻近层定向长钻孔抽采效果进行了考察，定向长钻孔瓦斯抽采量由最低的0.35到最高的1.03增加了65%、上隅角最高处浓度为0.58%相较最低处的0.16%下降了72%，由此可知，上邻近层定向长钻孔可有效减少上邻近层卸压瓦斯向采场空间涌出，实现煤与瓦斯高效安全共采。

The occurrence of close distance coal seam group is widely distributed. Under the condition of mining, there are many sources of gas emission during the mining of working face, and the law of gas migration is more complicated than that of single coal seam mining. It is urgent to take targeted technical measures. In view of the problems of ' one layer mining, multi-layer pressure relief ' and difficult gas control in the mining of close-range outburst dangerous coal seams, this paper takes the No.2 coal seam of Tunlan Coal Mine as the engineering background, and uses FLAC3D software to simulate the stress field, displacement field and plastic zone distribution of surrounding rock during the mining of working face. Based on this, the construction scheme of directional long drilling in the upper adjacent layer is established. The research results show that the width of O-ring increases with the increase of coal seam excavation. When the mining footage of Tunlan No.2 coal seam working face reaches 30 m, the range of O-ring has reached 15 m. A large amount of pressure relief gas is desorbed, and the caving zone and the fracture zone communicate the overlying coal seam. The effect of directional long drilling in the upper adjacent layer is investigated. The gas extraction amount of directional long drilling increases from the lowest 0.35 to the highest 1.03 by 65 %, and the concentration at the highest corner is 0.58 %, which is 72 % lower than the lowest 0.16 %. It can be seen that the directional long drilling in the upper adjacent layer can effectively reduce the pressure relief gas of the upper adjacent layer to the stope space, and realize the efficient and safe co-mining of coal and gas.

金廷旭，谢建林，孙晓元. 近距离突出危险煤层群卸压瓦斯抽采技术研究[J]. 煤炭与化工, 2023, 46(10): 108-114.

Jin Tingxu, Xie Jianlin, Sun Xiaoyuan. Study on pressure relief gas extraction technology of close distance outburst dangerous coal seam group. CCI, 2023, 46(10): 108-114.