水力压裂技术在高瓦斯低透气性矿井中的应用

针对高瓦斯低透气性矿井瓦斯难以抽放的问题,结合高压水动力特性,提出采用高压水力压裂煤层提高煤层透气性。根据第一强度理论,通过分析压裂孔周围应力状态,建立煤体破裂条件,研究煤体在高压水作用下的破裂机理,推导出压裂孔起裂压力临界值公式;另根据平煤十矿煤层赋存特性,计算出煤层水力压裂所需的启裂压力,优化水力压裂参数;研制出水力压裂设备及工艺,并成功应用于该矿;数据分析表明,压裂后煤层瓦斯抽采流量、浓度均提高5倍以上。

Application the hydraulic fracturing technology in the highn pressure and low permeability mine

To solve the gas drainage problem of the high gas and low permeability mine, based on the features of the high pressure water, the hydraulic fracturing technology is proposed to improve the gas drainage rate. According to the first strength theory, through analyzing the stress around the borehole, the broken mechanism of the coal under high pressure is studied and the function of critical value is obtained. In addition, based on the coal features of the tenth mine of the Pingdingshan, the fracturing pressure is calculated and the hydraulic fracturing parameter is optimized. The equipment of the hydraulic fracturing technology is developed and applied successfully in the mine. And it is found that the gas drainage flux and concentration are improved with more than 5 times.