煤层高压气水混压技术及其有效影响半径测试研究

Research on high pressure gas-water mixed pressure technology in coal seam and its effective influence radius test

针对现在煤层纳米级孔隙内瓦斯抽采率低的难题,研发了煤层高压气水混压技术,给出了其高压气水混压的技术原理,即依靠高吸附能力的水分置换出甲烷,再注入高压空气驱替孔裂隙中的水分解除“水锁”效应。在川煤绿水洞煤矿开展了初步现场试验,施工3组气水混注考察钻孔,取样分析了采取技术措施后的残余瓦斯含量在1.76~6.75 m3/t之间(除去一个异常点的含量为10.51 m3/t),通过与原始瓦斯含量(9.02 m3/t)对比,最终确定其气水混注有效影响半径最大可以达到48 m。

Aiming at the problem of low gas drainage rate in nanopores of coal seam,the high pressure gas-water mixed pressure technology in coal seam was developed,and the technical principle was given,that was,methane was replaced by water with high adsorption capacity,and then the water lock effect was relieved by injecting high-pressure air to displace water in pores and fissures.The preliminary field test was carried out in Lvshuidong Coal Mine of Sichuan Coal Industry Group.Three groups of gas-water mixed injection inspection boreholes were constructed,and after adopting the technology,the measured residual gas content was between 1.75 and 6.75 m3/t expect an unnormal value of 10.51m3/t.Compared with the original gas content(9.02 m3/t),the maximum effective influence radius of gas-water mixed injection could reach 48 m.