下向穿层钻孔水力冲孔卸压增透强化抽采瓦斯技术研究

为提高预抽煤层瓦斯消突效果,本文试验了下向穿层钻孔卸压增透强化抽采技术,并在高抽巷区域预抽钻孔中进行了实践。水力冲孔实施后,钻孔的卸压影响范围增大,钻孔周围的煤体变形和透气性增大,抽采瓦斯效果显著提高。对比水力冲孔前后的钻孔瓦斯压力和抽采量变化表明,水力冲孔影响半径达到10m,有效影响半径大于5m。与水力冲孔钻孔平距2.5m抽采孔,瓦斯抽采纯量增大4.25倍,平距5m~6m抽采孔瓦斯抽采纯量增大1.5倍。水力冲孔卸压增透强化抽采技术卸压增透范围大,提高抽采效果显著,为高突煤层预抽消突提供了一种行之有效的方法,值得在低透气性高瓦斯突出煤层消突实践中推广应用。

Research on Enhanced Gas Drainage of Stress Relief and Permeability Improvement by Hydraulic Punching in Downward Bores

In order to improve effect of gas drainage,the paper presents a technique of stress relief and permeability improvement by hydraulic punching.The experiment is implemented in downward bores of high drainage tunnel.Hydraulic punching induces range expanse of stress relief,permeability improvement and significant enhancement of gas drainage.By contrast with the gas pressure and the volume of bores drainage from start to finish,the radius of influence is expanded to 10m,the significant part is greater than 5m.The volume of bore drainage with 2.5m horizontal distance to hydraulic punching one is 4.25 times more than normal one,which with 5m~6m horizontal distance to hydraulic punching one is increased 1.5-fold.The advantages of the technique are significant effect.Thus it is an effective method and worth popularizing in outburst elimination of low permeability and high gas outburst coal seams.