潞安矿区煤储层特征及瓦斯含量分布规律研究

摘要

为了掌握潞安矿区3号煤层储层特征及瓦斯赋存规律，从煤层埋深、煤变质程度、煤层渗透性、煤的吸附特性、煤体结构等方面系统分析了煤储层特征，在此基础上着重对煤层瓦斯含量与煤层埋深、煤变质程度、煤层水分和灰分的定量关系进行分析，建立了煤层瓦斯含量模型，得到了煤层瓦斯含量的分布规律。结果表明：潞安矿区3号煤层厚度大，赋存稳定，埋藏深度大，变质程度高，Lang-muir体积较大，Langmuir压力较小，有利于瓦斯在煤层中富集成藏；矿区内多发育碎裂煤和碎粒煤，局部存在糜棱煤，煤体结构破碎，煤层渗透性较差，瓦斯抽采利用难度大；各区块在相同煤层埋深条件下，南部长治区块瓦斯含量最大，北部襄垣区块瓦斯含量次之，中部潞安区块瓦斯含量最小。%In order to obtain No.3 coal seam reservoir features and gas distribution law in Lu'an Mining Area,the seam reservoir features were systematically analyzed from the seam depth,coal metamorphism degree,seam permeability,coal adsorption features,coal structure and other aspects.Based on the circumstances,the quantitative relationship of the coal gas content and seam depth,coal metamorphism de-gree,seam moisture and ash content were studied,a seam gas content model was established and the distribution law of the seam gas con-tent was obtained.The results showed that No.3 seam in Lu'an Mining Area with high in thickness,stable in deposition,deep the depth, high in metamorphism degree,large in Langmuir volume and low in Langmuir pressure would be favorable to the gas enrichment deposition in the seam.In the mining area,there were many developed broken coal and broken partical coal,and partially mylonite coal.The coal struc-ture was broken,the seam permeability was poor,the permeability was lower than the domestic average level and a gas drainage and utiliza-tion of the seam would be high difficult.Under the same seam depth condition of each block,the gas content in the north part of Changzhi Block would be highest,the gas content in the south part of Xiangyuan Block would be second and the gas content in the middle part of Lu'an Block would be the lowest.