晋城无烟煤煤中CH_4和CO_2运移规律研究  

The migration of CH_4 and CO_2 in Jincheng anthracite coal

作　　者：张松航[1] 唐书恒[1] 万毅[1] 李忠诚[1] 张静平[1] 

机构地区：[1]中国地质大学海相储层演化与油气富集机理教育部重点实验室能源学院,北京100083

出　　处：《中国矿业大学学报》2012年第5期770-775,共6页Journal of China University of Mining & Technology

基　　金：国家重点基础研究发展计划(973)项目(2009CB219604);国家自然科学基金重点及面上项目(40730422,40972108);国家科技重大专项(2011ZX05034-003)

摘　　要：基于三轴应力条件下,煤岩有效应力、吸附膨胀量和渗透率的一体测试,研究了晋城无烟煤吸附甲烷和二氧化碳后,渗透性随有效应力改变和煤岩吸附膨胀效应的变化规律.认为煤岩吸附膨胀量和孔隙压力的关系可用兰氏方程描述;煤岩渗透性同有效应力、吸附膨胀量均呈负指数函数关系,同时结果表明:甲烷和二氧化碳在晋城无烟煤中的扩散方式不同,煤岩对甲烷的吸附膨胀符合单孔气体扩散模型,而对二氧化碳的吸附膨胀符合双孔气体扩散模型,且甲烷的吸附膨胀速率小于二氧化碳的吸附膨胀速率;煤岩饱和吸附后,各孔隙压力条件下的初始渗透率与孔隙压力呈幂函数关系减小.针对晋城无烟煤,同等条件下煤岩吸附甲烷后的渗透率为吸附二氧化碳后渗透率的1.14～1.51倍,大部分在1.30倍左右.Base on the experimental tests of effective stress, adsorption swelling and permeabili- ty under triaxial stress, the change of dynamic permeability as a function of applied stress, pore pressure and swelling induced by adsorption were investigated at Jincheng anthracite coal. It was proved that the relation of sorption induced swelling, the pore pressure could be de- scribed by Langmuir style function and the permeability of coal shows negative exponential re- lationship with effective stress as well as sorption induced swelling. Meanwhile, the results show that the swelling rates of anthracite coal with methane and carbon dioxide are different. The former is relatively low with single pore gas diffusion model and the later is relatively high with double pore gas diffusion model. In addition, the initial permeability of coal after saturat- ed adsorption at different pore pressure shows power function relationship with pore pressure. Under the same condition, the permeability of Jincheng anthracite coal was 1. 14-1.51times （the normal one is about 1.30） after adsorbed methane than adsorbed carbon dioxide.

关 键 词：煤层气 二氧化碳 吸附膨胀 有效应力 渗透率 沁水盆地 

分 类 号：P618.11[天文地球—矿床学]