穿层瓦斯抽采钻孔渗流演化特征  

Seepage evolution characteristics of gas extraction borehole through strata

作　　者：王慧恩 WANG Huien(Shanxi Gaoping Qinglong Tongchang Coal Industry Co.,Ltd.,Jincheng 048400,China)

机构地区：[1]山西高平青龙同昌煤业有限公司,山西晋城048400

出　　处：《陕西煤炭》2025年第1期37-40,63,共5页Shaanxi Coal

摘　　要：为治理青龙同昌煤矿9号与15号煤层群瓦斯问题,采取底板穿层钻孔方式进行煤层群瓦斯抽采。采用COMSOL数值模拟软件建立数值模型,设计分析了3种钻孔直径(∅75 mm、∅94 mm、∅113 mm)与4种抽采时间(30 d、60 d、90 d、120 d)下的煤层瓦斯渗流状态,并在现场开展工业试验,对瓦斯抽采有效半径,瓦斯抽采浓度进行监测分析。结果表明,增加瓦斯抽采钻孔直径可以提升瓦斯抽采效率,但提升效果表现为非线性的弱化关系,瓦斯压力分布曲线的几何弧度随着抽采时间的增加逐渐减小,瓦斯压力随抽采时间表现为下降趋势。最终选取∅94 mm钻孔直径与120 d抽采时间作为抽采参数。15号煤层的瓦斯抽采有效半径的扩展速度相比于9号煤层更为缓慢,15号煤层数据与数值模拟计算结果基本吻合。在抽采120 d后,经技术判定,抽采钻孔3 m内的瓦斯压力均降低至0.70 MPa以下。In order to control the gas problem of 9#and 15#coal seam group in Tongchang Coal Mine,gas extraction is carried out by floor penetrating drilling.A numerical model was established using COMSOL numerical simulation software to analyze the gas seepage state of coal seam with 3 borehole diameters(∅75 mm,∅94 mm,∅113 mm)and 4 extraction times(30 d,60 d,90 d,120 d).Industrial tests were carried out in the field.The concentration of gas extraction is monitored and analyzed.The results show that increasing the diameter of the gas extraction borehole can improve the gas extraction efficiency,but the improvement effect shows a nonlinear weakening relationship.The geometric curvature of the gas pressure distribution curve gradually decreases with the increase of extraction time,and the gas pressure shows a decreasing trend with the extraction time.The extraction parameters of∅94 mm bore diameter and 120 d pumping time were selected.The effective radius of gas extraction of 15#coal seam expands more slowly than that of 9#coal seam,and the data of 15#coal seam is basically consistent with the numerical simulation results.After 120 days of extraction,the gas pressure within 3 m of the extraction borehole was reduced to below 0.70 MPa.

关 键 词：穿层钻孔 瓦斯抽采 数值模拟 工业试验 瓦斯渗流 

分 类 号：TD712.6[矿业工程—矿井通风与安全]