摘要
针对松软低透煤层瓦斯抽采钻孔塌孔严重、瓦斯抽采效果差、抽采达标周期长、抽掘采衔接紧张等问题,基于现有装备,提出了定向顺层钻孔"钻-冲-护"一体化低透煤层高效促抽瓦斯技术,该技术在长平煤矿实践表明:大功率定向钻机施工煤段长度达到340 m,煤段水力冲孔后总返煤量260.46 t,扩孔孔径φ0.87 m。对冲孔方式进行考察,发现回转冲孔方式和交叉冲孔方式效率优于水平冲孔方式。未采取下筛管工艺抽采钻孔平均瓦斯浓度为25.05%;全程下筛管护孔抽采钻孔平均瓦斯浓度为49.10%,一体化工艺下抽采钻孔百米瓦斯纯流量比普通钻孔水力冲孔护孔后抽采钻孔百米瓦斯纯流量提高了约11倍,瓦斯流量衰减系数降低了9.4%。瓦斯抽采浓度提高约2倍,百米抽采瓦斯纯量由0.08 m^(3)/min增至0.94 m^(3)/min,瓦斯抽采效果明显,保障了矿井的安全高效生产。
Aiming at the problem of serious hole collapse,poor gas drainage effect of gas drainage,extraction time is long and dig gas drainage bridging stress problem in soft and low permeability coal seam,based on the existing equipment,an efficient gas drainage technology of low permeability coal seam integrating"drilling,punching and protecting"with directional bedding drilling was put forward.The practice of this technology in Changping coal mine shows that the length of coal section constructed by high-power directional drilling rig is up to 340 m,the total amount of returned coal after hydraulic punching in the coal section is 260.46 t,and the pore diameter of reaming isφ0.87 m.Through investigating the punching method,it is found that the efficiency of rotary punching and cross punching is better than that of horizontal punching.The average gas concentration in the drilling hole without lower screen was 25.05%.The average gas concentration of the entire drainage hole with the sieve tube retaining hole is 49.10%.The pure gas flow rate of the drainage hole in the integrated process is about 11 times higher than that of the ordinary hydraulic drilling after the drainage hole retaining hole,and the gas flow attenuation coefficient is reduced by 9.4%.The gas concentration of the drilling hole increased by about 2 times,and average flow rate of single-hole per 100 m gas increased from 0.08 m^(3)/min to 0.94 m^(3)/min.The gas extraction effect was obvious,guaranteeing the safe and efficient production of the mine.
作者
辛宪耀
XIN Xianyao(Shanxi Changping Coal Industry Co.,Ltd.,Gaoping 048400,China)
出处
《煤炭技术》
CAS
北大核心
2022年第2期128-131,共4页
Coal Technology
关键词
松软低透煤层
瓦斯抽采
定向顺层钻孔
“钻-冲-护”一体化
冲孔方式
soft and low permeability coal seam
gas drainage
directional bedding drilling
integrated technology of"drilling
punching and protecting"
punching way
