顺层交叉钻孔预抽瓦斯技术在高瓦斯低透煤层的试验研究

Experimental Research on Gas Pre-drainage Technology with Cross Borehole Drilled Along Seam in High Gassy and Low Permeability Mine

针对高瓦斯低透煤层瓦斯预抽效果不佳、抽采工艺参数设置不够合理的问题,通过对交叉钻孔围岩塑性区应力叠加效应的理论分析,阐述了其增透利抽、提高本煤层瓦斯预抽效果的机理,罗列了交叉钻孔施工参数要求;结合某矿12103工作面交叉钻孔预抽瓦斯技术的试验应用,量化对比分析了两种钻孔瓦斯预抽效果。结果表明:在不增加工程量的条件下,与传统的平行钻孔相比,交叉布孔方式可将本煤层瓦斯预抽率提高0.77倍左右,有效改善了高瓦斯低透煤层瓦斯预抽效果,降低了工作面回采时瓦斯事故发生的概率,为矿井安全生产增添了保障。

According to the problem of poor gas pre pumping effect and setting process parameters is not reasonable in high gassy and low permeability coal seam,by the theoretical analysis of stress superposition effect of plastic zone at the surrounding of cross borehole rock,the mechanism of improving the penetration and effect of gas pre-drainage with them in the coal seam is described,listing the construction parameters requirements of cross borehole. Combined with the experimental application of the gas pre-drainage technology with cross boreholes in No 12103 mining face of a certain coal mine,the gas pre-drainage effect of two-kind borehole is compared and analyzed quantitatively. The results show that under the condition of not increasing the amount of project,the pre-drainage rate is increased about 0. 77 times by cross boreholes compared with the traditional parallel boreholes,improving the effect of gas pre-drainage in high gassy and low permeability coal seam,reducing the probability of the occurrence of gas accidents when working face mining,protecting the safety of mine production.