柴东石炭系页岩微观孔隙结构与页岩气等温吸附研究  

Study of microscopic pore structure and adsorption isothermal of carboniferous shale,Eastern Qaidam Basin

作　　者：刘圣鑫 钟建华 马寅生[2,3] 尹成明[2,3] 刘成林[2,3] 李宗星[2] 刘选 李勇[1] 刘晓光 

机构地区：[1]中国石油大学地球科学与技术学院,山东青岛266580 [2]中国地质科学院地质力学研究所,北京100081 [3]中国地质科学院页岩油气评价重点实验室,北京100081

出　　处：《中国石油大学学报（自然科学版）》2015年第1期33-42,共10页Journal of China University of Petroleum(Edition of Natural Science)

基　　金：国土资源大调查综合研究类项目(12120113040000-3)

摘　　要：基于柴达木盆地东部石炭系泥页岩的孔隙结构分析,结合甲烷和二氧化碳在泥页岩中的高压等温吸附实验,对超临界条件下页岩气等温吸附特征进行研究,探讨页岩气的吸附机制。结果表明:柴达木盆地东部石炭系泥页岩具有多尺度孔隙结构,微孔比较发育,微孔比表面积对BET比表面积有较大的贡献;甲烷Langmuir吸附量随微孔比表面积或微孔体积的增加而增加,两者呈正相关性,同时受到微孔大小分布的影响;在超临界条件下,简单的Langmuir方程可近似拟合甲烷吸附的实验数据,而修改的微孔充填(Dubinin Radushkevich,D-R+K)超临界吸附模型对甲烷和二氧化碳吸附数据的拟合效果最好;吸附气可能主要以微孔充填的方式存在,而微孔为吸附气的主要储集空间。By analyzing pore structure of the carboniferous shale,Qaidam Basin,the isothermal adsorption features of shale gas under supercritical conditions were studied using shale gas high-pressure isothermal absorption experiments,and then the adsorption mechanisms of shale gas were discussed. The results show that mud shale is characterized by multi-scale pore structures,pore development,and larger contribution from micropore specific surface area; increasing methane adsorption quantity with the increase of pore specific surface area,or micropore volume has a positive correlation in between;under supercritical conditions,simple Langmuir equation can fit the experimental data of methane adsorption in general,but modified pore filling model（ Dubinin Radushkevich,D-R ＋ K） fit the data of supercritical adsorption of methane and carbon dioxide absorption best; adsorbed gas may exist in the form of pore filling,and micropore is the main reservoir for the adsorbed gas.

关 键 词：孔隙结构 超临界吸附 LANGMUIR方程 Dubinin Radushkevich方程 

分 类 号：TE135[石油与天然气工程—油气勘探]