大佛寺低阶煤瓦斯储层的渗透性及其关键受控因素分析

Gas Permeability and Its Key Controlling Factors of Low-ranked Coal Seams in Dafosi Mine

彬长矿区大佛寺煤矿井田具有丰富的煤层气资源,瓦斯抽采的关键因素为煤层中瓦斯运移的难易程度,即渗透性。通过现场取样、实验室制样并采用煤样渗流实验系统进行测试,分析煤层渗透性大小及其关键受控因素,煤样垂直层理方向瓦斯流动通道与平行层理相比发育较少,水分进入煤体后阻塞瓦斯流动通道,瓦斯在垂直层理方向的运移受其影响更大,渗透率随着煤样含水率增加显著下降,不利于瓦斯抽采。

Dafosi Coal Field in Binchang Mining Area is rich in coalbed methane resources.The key factor of gas drainage is the difficulty of gas migration in coal seam,namely permeability.The coal seam permeability and its key control factors are analyzed by on-site sampling,laboratory samples preparation and coal samples seepage test system.The gas flow channel in the vertical bedding direction of the coal sample is less developed than the parallel bedding.The moisture enters the coal body and blocks the gas flow channel,which have more effect on the gas migration in the vertical bedding direction.And the permeability decreases significantly with the increase of moisture content of coal sample,which is not conducive to gas drainage.