为了查明高、低煤阶煤储层孔隙分布差异性对煤层气富集与渗透运移的影响,根据高、低煤阶煤岩样品的压汞、平衡水等温吸附试验结果,分析了高、低煤阶煤孔隙发育特征,对比了高、低煤阶煤孔隙体积分形差异。结果表明:高煤阶煤孔隙度低、渗流孔含量小、"墨水瓶"型的半封闭孔发育导致孔隙连通性降低、渗流能力差;微孔含量高、水分含量低、吸附能力强,有利于煤层气富集。低煤阶煤孔隙度大,大、中、过渡孔比孔容均较大,孔隙连通性好,渗流能力强;比表面积小、水分含量高,致使吸附能力低下。高煤阶储层煤层气开发应提高渗透性而低煤阶煤层气开发则应首选优势富气区。

In order to investigate the difference of the pore distribution in the coal reservoirs with high and low rank coal affected to the coal bed methane enrichme nt and the penetration migration,according to the pressurized mercury and balanced water isothermal adsorption experiment results of the high and low rank coal sampl es,the paper analyzed the pore development features of the high and low rank coal and compared the difference of the pore volume fractals in the high and low rank co al.The results showed that low porosity of the high rank coal, small content of the influent pore,inkstand type semi-sealed pore development would cause a connection r eduction of the pore,a poor influent capacity,a high micro pore content,a low moisture content and a high adsorption capacity and would be favorable to the enrichment of coal bed methane.The porosity of low rank coal would be large.The specific pore volume of the large,medium and transition pore all would be large,the connection of the pores would be good and the influent capacity would be high. The small specific surface area and high moisture content would cause the adsorption capacity reduce d.The coal bed methane development of high rank coal reservoir should improve permeability and coal bed methane development of low rank coal reservoir should be fi rst to select methane enrichment zone.

国家重点基础研究发展计划(973计划)资助项目(2009CB219605)；新疆维吾尔自治区“天山学者”计划资助项目(2011ZX05-03404)；2011年江苏省研究生科研创新计划资助项目(CXZZ11-0305)；