关键词: 瓦斯治理, 底板定向拦截钻孔, 瓦斯抽采, 瓦斯含量, 瓦斯压力

Abstract: Aiming at the problem of gas exceeding the limit caused by the gas emission from the 9 coal seam of the lower adjacent layer of Qidong Coal Mine to the 82 coal working face，the 8235 working face is taken as the research object，and the gas control technology of the directional interception borehole in the floor is proposed and implemented. By accurately intercepting the gas emission channel of the lower adjacent layer through directional drilling，the gas content of the adjacent layer is fundamentally reduced， and the problems of traditional treatment methods ( such as high-level drilling，replacing roadways with holes，etc. ) that only alleviate gas emission and fail to address both symptoms and root causes are solved. Based on the law of gas migration and geological conditions，the directional drilling trajectory of the bottom plate is designed to control the drilling spacing equal or lesser than 20 m，and the final hole is located to the fault tectonic zone. The stability of the extraction system is ensured by using two plugging and one grout⁃ ing bag grouting sealing technology and ϕ73 mm steel screen pipe hole protection technology. Through real�time trajectory measurement and dynamic adjustment of drilling parameters，the construction accuracy is guaranteed. The results show that under the standard condition，the pure amount of gas extraction is in⁃ creased from 25 m3 /min to 40 m3 /min，and the average is maintained at 10 m3 /min. The gas content of No.9coal in the extraction area decreased from 4.109 8 m3 /t to 2.661 1 m3 /t ( a decrease of 54% )，and the gas pressure decreased from 0.46 MPa to 0.202 5 MPa ( a decrease of 127% )，which significantly reduced the risk of gas emission from adjacent layers. At the same time，the gas concentration in the return air of the working face is stable below 0.25%，and the gas concentration in the upper corner is reduced from 0.54% to 0.35%，which effectively avoids the problem of exceeding the limit. This technology realizes the source pre⁃ vention and control of gas control in adjacent strata by accurately intercepting the gas migration path，and provides an innovative solution for gas control in adjacent strata under high outburst mines.

Key words: gas control, floor directional interception drilling, gas extraction, gas content, gas pressure