复杂地质条件下深部煤层瓦斯高效抽采技术探索

Exploration on efficient gas extraction technology of deep coal seam under complex geological conditions

我国大部分煤矿区地质条件复杂,开采深度逐年增加,瓦斯抽采困难。与浅部煤炭资源开采相比,深部煤炭资源开采所面临的瓦斯问题将更复杂。理论分析结果表明,随着开采深度增加,钻孔周边应力条件更复杂,钻孔稳定性变差,易出现塌孔,钻孔有效抽采半径减小,瓦斯抽采效果降低。为了探索适合于复杂地质条件下深部煤层开采瓦斯治理的技术措施,在分析了不同深度条件下钻孔抽采效率的情况下,以淮南矿区为例,分别进行了穿层钻孔水力加砂压裂、顺层长钻孔“一孔两消”以及地面钻井掏煤辅助消突技术。试验结果表明,三种技术对于区域瓦斯强化抽采、工作面高效消突以及深部高压强突煤层石门揭煤均具有明显效果。试验成果为我国复杂地质条件下深部煤层瓦斯高效治理提供技术支撑和借鉴。

The geological conditions of most coal mining areas in China are complex,the mining depth increases year by year,and the gas drainage is difficult.Compared with shallow coal resources mining,the gas problem faced by deep coal resources mining will be more complex.The theoretical analysis results show that with the increase of mining depth,the stress conditions around the borehole become more complex,the borehole stability becomes worse,the borehole is prone to collapse,the effective drainage radius of the borehole is reduced,and the gas drainage effect is reduced.In order to explore the technical measures suitable for gas control in deep coal seam mining under complex geological conditions,taking Huainan Mining Area as an example,the hydraulic sand fracturing of through layer drilling,the“one hole and two elimination”of bedding long drilling and the auxiliary outburst elimination technology of coal cutting by surface drilling were carried out respectively.The test results show that the three technologies have obvious effects on regional gas enhanced drainage,highefficiency outburst elimination in working face and crosscut coal uncovering in deep high-pressure and strong outburst coal seam.The test results provide technical support and technical reference for the efficient treatment of deep coal seam gas under complex geological conditions in China.