摘要
为了描述煤层气开采和煤层瓦斯抽采过程中煤层各向异性渗透率的演化行为,构建了有效应力变化和瓦斯吸附/解吸双重作用下的煤层正交各向异性渗透率演化模型,推导了立方型和指数型两种模型表达式并对其可靠性进行了验证.基于构建的煤层正交各向异性渗透率演化模型,模拟了煤层渗透率各向异性对顺层钻孔预抽瓦斯的影响.结果表明:当渗透率各向异性程度相同时,随着钻孔与最大渗透率方向夹角的增大,单孔抽采流量逐渐升高;钻孔方位变化对单孔抽采流量的影响与渗透率各向异性程度呈正比例关系.
In order to represent the anisotropic coal permeability evolution behavior during coalbed methane recovery and coal seam methane drainage,an orthotropic coal permeability model considering the effects of both effective stress change and gas sorption was developed.Two model representations were proposed for this model.One was a cubic representation and the other was an exponential one.Both model representations were validated with literature coal permeability data.Based on the proposed permeability model,the effects of permeability anisotropy on coal seam methane drainage with in-seam boreholes were simulated.When permeability anisotropy was constant,the drainage flux were positively proportional to the angle between the drainage borehole and the maximum permeability direction.The effects of borehole direction on drainage flux were positively proportional to permeability anisotropy.The results show that readjusting borehole direction and using permeability anisotropy is beneficial for coal seam methane drainage with in-seam boreholes.
作者
臧杰
王凯
刘昂
张翔
闫志铭
ZANG Jie;WANG Kai;LIU Ang;ZHANG Xiang;YAN Zhiming(Beijing Key Laboratory for Precise Mining of Intergrown Energy and Resources,State Key Laboratory of Coal Resources and Safe Mining,China University of Mining&Technology(Beijing),Beijing 100083,China;College of Resource&Safety Engineering,China University of Mining&Technology(Beijing),Beijing 100083,China;Yangquan Coal Industry(Group)Co Ltd,Yangquan,Shanxi 045000,China)
出处
《中国矿业大学学报》
EI
CAS
CSCD
北大核心
2019年第1期36-45,共10页
Journal of China University of Mining & Technology
基金
国家重点研发计划项目(2016YFC0600708
2016YFC0801402)
国家自然科学基金青年基金项目(51804312)
