成庄矿大采高工作面瓦斯分区段抽采方法研究

Study on extraction method of gas zone section of large mining height working face in Chengzhuang Mine

针对成庄矿3号煤层4323工作面回采过程中存在的瓦斯浓度高问题,采用理论分析与现场监测现结合的方法,研究了该工作面瓦斯存在的风险性及其综合抽采方法。结果表明,目前工作面实际供风量不能满足工作面实际需风量要求,有可能发生瓦斯突出风险,必须对瓦斯进行抽采。研究提出了地表钻井瓦斯抽采、采空区布设管理及裂隙带钻孔抽采、工作面顺层及穿层抽采相结合的分区段瓦斯抽采方法。通过现场实践,工作面瓦斯平均有效抽采量达到涌出量的86%;工作面上隅角最大瓦斯浓度变化范围为0.55%~0.72%,平均瓦斯浓度变化范围为0.17%~0.46%,没有出现瓦斯超限情况,对上隅角进行瓦斯抽采取得了良好的效果;在采空区瓦斯总体涌出量一定的条件下,采空区布设管路及裂隙带钻孔瓦斯抽采表现为互补关系,能够实现对采空区瓦斯的有效抽采,保证工作面回采安全。

In view of the problem of high gas concentration in 4323 working face of No.3 coal seam in Chengzhuang Mine,the paper studies the gas risk and comprehensive extraction method of the working face by combining theoretical analysis and on-site monitoring.The results show that the current actual air supply of the working face can not meet the actual air demand of the working face,there may be a risk of gas outburst,gas must be extracted.In this paper,a gas extraction method of zone segment is put forward,which is combined with surface drilling,gob layout management,fracture zone drilling,working face bedding and through bed pumping.Through field practice,the average effective gas extraction amount of the working face reaches 86%of the gushing amount.The maximum gas concentration in the corner of the working surface varies from 0.55%to 0.72%,and the average gas concentration varies from 0.17%to 0.46%.There is no overlimit of gas,and the gas extraction in the upper corner has a good effect.Under the condition that the total amount of gas emission in goaf is certain,the gas extraction by laying pipes in goaf and drilling holes in fissured zone is complementary,which can realize effective gas extraction in goaf and ensure the safety of working face.