摘要
地面钻井抽采瓦斯已成为解决高瓦斯矿井安全问题的有效方法,但我国煤层的渗透率普遍较低,需要进行人工增透,其最有效的方法之一就是水力压裂。在对瓦斯抽采单井压裂效果分析的基础上,利用有限元分析软件RFPA对多井压裂效果进行了数值分析,结果表明:单井压裂时,裂缝在井周两侧沿最大水平主应力方向延伸;多井压裂设计时,采用对角线沿最大水平主应力方向的菱形布井方式,能在煤层中产生充分发育的裂隙和损伤区域,达到压裂煤层的目的;模型的边界条件对模拟结果产生较大影响,施加围压更符合实际情况。
Gas drainage by surface vertical wells has become an efficient method for solving the safety problems of high gassy mines,but in our coal mines,the permeability of coal seams was generally low and their permeability needs to be increased artificially,one of the most effective methods is hydraulic fracturing.In this paper,numerical analysis was made on gas drainage effect by multi-well fracturing with the finite element analysis software RFPA based on the analysis of the gas drainage effect by single well fracturing.The results showed that in the case of single well fracturing,the cracks on both sides of the well extended along the direction of the maximum horizontal principal stress;when multi-well fracturing design was adopted,the wells were arranged in a rhombus with the diagonal line along the direction of the maximum horizontal principal stress,in this case,the fully developed cracks and damaging areas in coal-bed can be formed,thus fracturing the coal seam;the boundary conditions of the model have a great effect on the simulation results and exerting a confining pressure more tallied with the actual situation.
出处
《矿业安全与环保》
北大核心
2012年第6期7-9,101,共3页
Mining Safety & Environmental Protection
基金
国家自然科学基金项目(11102226)
中国民航大学科研启动基金项目(08QD03X)