【作者】 毛飞； 唐建新； 赵宁德； 李志强； 陈久福；

【Author】 Mao Fei~(1,2),Tang Jianxin~1,Zhao Ningde~2,Li Zhiqiang~3,Chen Jiufu~2 (1.National and Local jointly Engineering Laboratory of Complicated CBM Drainage,Chongqing University, Chongqing 400044,China;2.Chongqing Energy Investment Group,Chongqing 400704,China; 3.Research Institute of Gas Geology,Henan Polytechnic University,Jiaozuo 454000,China)

【机构】 重庆大学复杂煤气层瓦斯抽采国家地方联合工程实验室； 重庆市能源投资集团； 河南理工大学瓦斯地质研究所；

【摘要】 通过对比国内外数据,指出导致重庆地区瓦斯突出呈现三大特征的根本原因是渗透率极低。进一步对煤体孔和裂隙的测试分析得知,重庆地区煤层微孔多,大孔少;总孔体积大,有效连通孔体积小,这有利于瓦斯储集而不利于其流动。不同放大倍率下裂隙密度不同,煤层长裂隙少短裂隙多,而裂隙宽度相差不大,裂隙呈锯齿状,其发展的方向性不明显,裂隙充填物以硬质无机物为主。提出煤层具有压敏效应和水敏效应,且"双敏效应"具有"双刃剑"特征。在增透措施上要变被动"排"为主动"驱"瓦斯,从而消除瓦斯富集的场所,为瓦斯逸散提供通道。更多还原

【Abstract】 The comparative datas from home and abroad indicate that extra-low permeability of coal seam is the basic reason why the gas outbursts obviously demonstrate three features in Chongqing.Further analysis on the microstructure of coal pore and fracture show that,firsdy,the quantity of micropores is much more than that of macropores;the total volume of the pores is large while the volume of interconnected pores is small.This is helpful to gas storage but going against gas flow.Secondly,fracture density varys with magnification;there are many short fractures but only a few long fractures;all of the fractures are similar in width and in the form of zigzag;the directivity of fracture extension is irregular. Thirdly,fracture fillings are mainly based on hard inorganic matter.It is put forward that both pressure-sensitive effect and water sensitivity effect exist in the coal seam and they are "double-edged swords" to permeability.In order to increase the permeability,it is necessary to change passive exhausting into active driving,removing gas reservoir and providing a passageway for gas dissipation.更多还原