榆横北区中深埋煤层开采水力压裂技术实践

Hydraulic fracturing technology of middle and deep coal seam mining in northern Yuheng mining area

陕北侏罗纪煤田榆横北区内的矿井大多数处于初期开发阶段,且区内的煤层赋存条件差异较大,在其西侧中深埋矿井的矿山压力规律、顶板管理手段等方面的经验不足。为了探索该区域首采的2号煤层开采后,其坚硬顶板卸压、围岩释压等技术问题,以巴拉素煤矿为例,结合长距离定向钻和短距离常规钻的水力压裂技术,通过分析压裂数据曲线、相邻钻孔及锚索的出水情况及孔内窥视结果,对2102首采工作面切眼顶板水力压裂工程进行研究。结果表明,区内2号煤层顶板坚硬,煤层回采后自然垮落难度较大,采用长短钻结合的水力压裂技术,可有效释放煤层顶板的压力,解决矿压集中及悬顶的隐患威胁,确保工作面的安全开采。该水力压裂技术实践可为后期矿井相关矿压管理工作提供依据和借鉴。

Most of the mines in northern Yuheng mining area of Jurassic coalfield in northern Shaanxi Province are in the early stage of development,the occurrence conditions of coal seams in the area are quite different,and the experience in the mine pressure law and roof management in the middle and deep buried mine on the west side is still insufficient.In order to explore the technical problems of hard roof pressure relief and surrounding rock pressure relief after mining of No.2 coal seam,taking Balasu Coal Mine as an example,combined with the hydraulic fracturing technology of long directional drilling and short conventional drilling,by analyzing the fracturing data curve,the water discharge of adjacent borehole and anchor cable and the borehole peeping results,the cutting-hole roof hydraulic fracturing engineering of No.2102 initial mining face is studied.The results show that the roof of No.2 coal seam in the area is hard,and the natural collapse of coal seam after mining is more difficult.The hydraulic fracturing technology combined with long and short drilling can effectively release the pressure of the coal seam roof,solve the hidden danger of mine pressure concentration and hanging roof,and ensure the safe mining of the working face.The research and engineering practice of hydraulic fracturing technology can provide the basis and reference for the later mine pressure control.