Shaanxi Coalbed Methane Development Co., Ltd.

坚硬煤层通常来说具有硬度高、结构致密、渗水性较差等特点,而开采坚硬煤层存在推采效率低、截齿损耗大、煤尘浓度大等问题。为降低煤体硬度,破坏内部结构,减弱煤尘飞扬,采用千米定向钻施工钻孔,利用高压泵将水注入煤层,通过水力压裂使煤体软化,从而达到改善工作面作业环境的效果。以柠条塔煤矿S1206工作面为研究对象,在工作面切眼向回撤通道方向350m范围内布置16个深度350m、间距20m的钻孔,下入高压封孔器,采用每3m压裂1次的后退式压裂方式进行煤层软化。结果显示,该技术施工难度小,施工效率高,能够使推采效率提高17%,截齿损耗率减少109%,同时煤尘也能得到一定的抑制。

some problems in mining hard coal seam, such as low mining efficiency, large cutting loss and large coal dust concentration.In order to reduce the hardness of the coal body, destroy the internal structure and weaken the flying of coal dust, this paperuses kilometer directional drilling to construct drilling, uses high pressure pump to inject water into the seam, and softens thecoal body through hydraulic fracturing to improve the working environment of the working face. Taking the S1206 workingface of Ningtiaota Coal Mine as the research object, 16 drilling holes with a depth of 350 m and a spacing of 20 m were con-structed within the cutting eye of the working face to the direction of the retreat channel, and high pressure hole seals wereinserted. The backward fracturing method of fracturing once every 3m was used to soften the coal seam. The results show thatthe technology has low construction difficulty and high construction efficiency, which can increase the mining efficiency by17% , reduce the pick loss rate by 109% , and restrain the coal dust flying to some extent.