薄煤层本煤层瓦斯抽放钻孔有效抽排放半径测试

Test on Effective Drainage Radius of Thin Mining Coal Seam Gas Drainage Drilling

将钻孔瓦斯流量法和钻孔瓦斯压力降低法两种方法结合,通过现场施工瓦斯流量测试孔和压力测试孔的连续对比观测和分析,确定了朱家店煤矿4号煤层本煤层钻孔的有效抽排放半径,为薄煤层瓦斯抽放钻孔的布置和参数优化提供了基础参数。现场测试对比分析发现钻孔瓦斯流量法测试简单有效,技术经济方面优于瓦斯压力降低法。通过对瓦斯压力降低法测定的钻孔有效抽排放半径进行对比关联分析,结果表明钻孔的抽采负压对钻孔卸压范围(抽放半径)影响较小,可以考虑通过测定钻孔排放半径来推断钻孔抽放半径。

This article combines the two methods of gas drilling flow method and gas pressure decreasing method,according to the continuous observation and analysis of site construction gas flow test drilling and stress test drilling,determines the effective drainage radius of Zhujiadian No. 4 coal seam drilling,to provide basic parameters for layout and optimization of thin seam gas drainage drilling. According to the field test,gas drainage flow method is much simpler and more effective,technically and economically prevails the gas pressure decreasing method. According to the comparison and correlation analysis of effective gas drainage radius based on gas pressure decreasing method, the negative pressure drainage has little influence on drilling pressure relief range（drainage radius）,the drainage radius might be inferred by measuring pumping radius.