煤矿大直径定向高位钻孔瓦斯抽采技术研究

Research on gas drainage technology of large-diameter directionalhigh-level boreholes in coal mines

瓦斯治理是所有煤矿面临的重要问题,直接影响到矿井安全。在介绍定向高位钻孔瓦斯抽采意义及基本原理的基础上,利用Comsol软件构建了瓦斯抽采数值模型。通过模拟计算,确定的最优抽采压力为20 kPa、钻孔直径为120 mm或153 mm,裂隙带与顶板之间的距离在43~66 m。结合煤矿工作面实际情况并参考数值模拟结果,对大直径定向高位钻孔技术方案进行详细设计,共包含2个钻场,16个钻孔。通过实践应用发现此项技术达到了预期效果,使工作面上隅角位置瓦斯浓度降低了56.61%,降低到了安全标准范围以内,创造了很好的安全效益。

Gas control is an important issue faced by all coal mines and directly affects mine safety.On the basis of introducing the significance and basic principle of gas drainage in directional high-level drilling,a numerical simulation model of gas drainage is constructed by using Comsol software.Through simulation calculation,the optimal extraction pressure determined is 20 kPa,the borehole diameter is 120 mm or 153 mm,and the distance between the fracture zone and the roof is 43~66 m.Combined with the actual situation of the coal mine working face and with reference to the numerical simulation results,the technical scheme of large-diameter directional high-level drilling is designed in detail,including 2 drilling fields and 16 drilling holes.Through practical application,it is found that this technology has achieved the expected effect,reducing the gas concentration at the corners of the working face by 56.61%,which is within the range of safety standards,creating a good safety benefit.