突出低渗煤层水力压裂增透技术应用研究

Research on Application of Hydraulic Fracturing Test in Coal and Gas Outburst Coal Seam

针对绿塘煤矿井田区域可采煤层瓦斯含量大、压力高,透气系数低带来煤层瓦斯抽采困难等技术难题,设计采用BZW-200型水力压裂系统进行水力压裂试验,考察压裂前后煤层含水率、瓦斯抽采浓度、瓦斯抽采纯量等参数来检验压裂试验的效果并优化钻孔布置。应用研究表明:水力压裂对于该矿6_中煤层具有显著增透作用,透气性系数提高约25倍;水力压裂试验明显改善了煤层瓦斯基础参数;实施水力压裂后煤层瓦斯抽采浓度及抽采量显著增大,能有效提高瓦斯抽采效率,保证工作面安全回采。

In view of the problems of high gas content, high pressure and low gas permeability coefficient of coal seams in the Lvtang coal mine field, the BZW-200 hydraulic fracturing system was used to conduct the hydraulic fracturing test, the parameters such as coal seam moisture content, gas drainage concentration and gas extraction slag before and after cracking were investigated to test the effect of the fracturing test and optimize the drilling arrangement. The applied research shows that hydraulic fracturing has significant anti-permeability effect on 6medium coal seams, and the gas permeability coefficient is increased by about 25 times. The hydraulic fracturing test can significantly improve the coalbed gas basic parameters; Coal seam gas drainage concentration and extraction amount increased significantly after hydraulic fracturing and can effectively improve gas drainage efficiency to ensure the safety of the work surface.