顶板穿层钻孔水力压裂现场数值模拟研究

Roof Layer Drilling Hydraulic Fracturing Field Numerical Simulation Research

以水力压裂增透机理为理论基础,以河南能源化工集团焦作煤业集团二1煤层的现场实测数据为参数,对演马庄矿22111运输巷顶板抽采巷打顶板穿层钻孔对煤体进行水力压裂,并运用RFPA2D-Flow软件进行水力压裂现场模拟。通过分析水力压裂过程中煤层裂隙的产生和贯通,以及压裂后钻孔周围主应力和渗透系数的变化,可知压裂后钻孔周围煤层主应力得到明显降低和渗透系数得到显著增加。并通过现场水力压裂抽采数据分析得出:压裂孔影响区域单孔日均抽放纯瓦斯流量是压裂孔未影响区域组抽采孔日均瓦斯抽采纯流量的35.35倍,抽采孔瓦斯浓度平均要提高1.34倍。水力压裂能显著增加抽采效果。

Based on the theory of hydraulic fracturing antireflection mechanism,take Henan Energy Chemical Group of Jiaozuo Mining Group 21 Coal Seam as a parameter to the actual measured data,to play 22111 transportation lane roof extraction layer drilling to hydraulic fracturing of coal body,and using RFPA2D- Flow hydraulic fracturing field simulation software in Mazhuang Coal Mine. Analyzed the produce of the coal seam in the process of hydraulic fracturing fracture and well versed in,and around the borehole after fracturing principal stress and the change of permeability coefficient,known around the borehole after fracturing coal principal stress is significantly reduced and the permeability coefficient increased significantly. And through the on- site hydraulic fracturing extraction data analysis： the hiatal area of influence puckering average daily drainage is pure gas flow pressure in no impact on regional group extraction holes per 35. 35 times that of the gas extraction from pure flow extraction pore gas concentration to increase 1. 34 times on average. Hydraulic fracturing can significantly increase the extraction effect.