地层条件下基于纳米级孔隙的煤层气扩散特征  

Coalbed methane diffusion characters based on nano-scaled pores under formation conditions

作　　者：闫宝珍[1] 王延斌[1] 倪小明[1] 

机构地区：[1]中国矿业大学(北京)资源与安全工程学院,北京100083

出　　处：《煤炭学报》2008年第6期657-660,共4页Journal of China Coal Society

基　　金：教育部博士科研基金资助项目(20060290003)

摘　　要：通过分析自由甲烷气体在地层条件下特性的变化，计算确定了甲烷不同扩散模式的孔径分布范围，并结合前期煤储层孔隙自然分类成果，就基于储层甲烷扩散的纳米级孔隙进行了初步划分，计算了不同扩散模式的扩散系数．研究表明，储层条件下，煤纳米级孔隙中甲烷存在3种扩散模式，且3种模式的扩散系数差别不大，比地表条件下扩散系数低1～2个数量级．Through analyzing the change of free methane gas characters under formation conditions, calculated and determined the pore size distribution of different methane diffusion models. Combining the early nature classification of coal pore structure, a preliminary nano-scaled pore division was developed based on reservoir methane diffusion and the coefficient of deferent diffusion model was calculated. The result comes to that there are 3 diffusion models of methane in nano-scaled pores and there is no significant difference among the 3 diffusion coefficient, which is 1 2 magnitudes lower than that of near-surface conditions.

关 键 词：地层条件 纳米级孔隙 煤层气 扩散特征 

分 类 号：P618.11[天文地球—矿床学]