低渗煤层气相压裂技术优化设计研究

Discussion on Optimization Design of Phase Fracturing Technology in Low Permeability Coalbed Methane

根据某矿煤层大多为低渗松软难抽采煤层,瓦斯治理技术难度大的特点,在原有气相压裂设计方案的基础上,对其进行优化,展开80 m双孔气相压裂预抽试验,给出了设计图及钻孔参数;为分析80m双孔压裂方案,“2+3”方案的抽采效果,选取井下相关地点进行了抽采效果评价,结果表明,优化的气相压裂设计方案全部并网后平均钻孔瓦斯抽采浓度提高了90%,平均抽采纯量提高了120%,达到了预期的抽采效果.

According to the characteristics that most of the coal seams in a mine are low permeability, soft and hard to extract coal seams, and the gas treatment technology is difficult, this paper optimizes the original gasfracturing design scheme based on the original gasfracturing design scheme,launches 80m double-hole gas fracturing pre-extraction test, and gives the design drawing and drilling parameters. In order to analyze the drainage effect ofthe 80m double-holefracturlng scheme and the “2+3” scheme, this paper selects relevant underground locations to evaluate the extraction effect. The results show that after the optimized gas fracturing design scheme is all connected to the grid, the average borehole gas extraction concentration is increased by 90%, the average extraction purity is increased by 120%, which reached the expected extraction effect.