多煤层水力压裂瓦斯抽采钻孔优化研究

Research on Optimization of Gas Extraction Borehole for Hydraulic Fracturing in Multiple Coal Seams

为了对水力压裂后的煤层更加经济有效的抽采瓦斯,以红阳二矿1205运输顺槽多煤层水力压裂后抽采钻孔布置为研究对象,设计了4种钻孔布置方案,对比分析了不同钻孔布置的瓦斯抽采效果。结果表明:水力压裂后距抽采孔越远的抽采钻孔的瓦斯抽采量越低,且单位面积煤层瓦斯抽采量随时间衰减;等效半径为5.5 m时,瓦斯预抽量约为4.24 m^3/t,此时剩余瓦斯含量为8 m^3/t,满足抽采要求。为了保证抽采效果和节约成本,该矿适宜选择的布孔方式为6 m×6 m。

In order to extract gas more economically and effectively from coal seams after hydraulic fracturing, studies the effect of gas extraction under different drilling holes arrangement after 1205 transport channel multi-seam hydraulic fracturing in Hongyang No.2 coal mine. The results show that the farther the drilling holes are from the pumping holes after hydraulic fracturing, the lower the gas extraction volume is, and the gas extraction volume per unit area of coal seam decreases with time.When the effective radius is 5.5 m, the gas pre-drainage capacity is about 4.24 m^3/t. At this time, the residual gas content is 8 m^3/t, which meets the requirements of extraction. In order to ensure the extraction effect and save the cost, the suitable hole layout method is selected as 6 m×6 m.