【摘要】 针对贵州西部煤矿区井下瓦斯抽采难度大、安全性低等问题,将地面抽采先进技术应用于煤矿瓦斯治理,开展碎软低渗煤层顶板水平井条带预抽技术方法研究。以对江南煤矿为例,通过井位优化布置、井眼轨迹设计、定向射孔和分段压裂等工艺流程研究,抽采工作面和掘进条带的煤层瓦斯,并通过储层数值模拟和编绘残余瓦斯含量分布图对抽采效果进行描述。预测结果显示,顶板水平分段压裂井抽采影响范围成条带状分布,并随抽采时间的持续以井眼为中心向两侧扩展,抽采强度随距井眼距离的增大逐渐降低,连续抽采5年,综合抽采率可达32%,掘进条带瓦斯含量可降至8 m~3/t以下。更多还原

【Abstract】 Gas extraction from the broken soft and low permeable coal seam is difficult with low safety in underground coal mine in Mining area of Western Guizhou Province. The advanced technology of ground extraction will be used for coal mine gas control,and the research on strip pre-pumping technology of horizontal well of broken soft and low permeability coal seam roof is carried out. Taking Duijiangnan Coal Mine as an example, through the study of technological process of optimizing well location, well trajectory design, directional perforation and staged fracturing, the coal seam gas in the working face and driving strip is extracted,and the reservoir numerical simulation and compilation of residual gas content distribution map were used to describe the extraction effect. The predicted results show that the influence range of horizontal sublevel fracturing wells on the roof is distributed in a strip, and expands to both sides with the borehole as the pumping time continues, and the pumping intensity decreases with the increase of the distance from the borehole. Continuous extraction for 5 years, the comprehensive extraction rate can reach 32%, and gas content in tunneling strip can be reduced to 8 m~3/t.更多还原