摘要
为了解决低渗透煤层气开发遇到挑战,依据双重介质扩散渗流和多组分吸附平衡理论,建立了注气开采煤层气多组分流体扩散渗流模型,利用数值方法研究了注气开采煤层气的增产机理.研究表明,注入二氧化碳气体不但减少了煤层甲烷的分压,加速了煤层甲烷的解吸,而且二氧化碳气体比甲烷气体更易吸附,竞争吸附置换煤层甲烷分子,从而提高了煤层气产量,结果表明注气开采煤层气是提高我国低渗透煤层气产量的有效途径.
In order to solve the problem of low seepage of methane in coal bed methane exploitation, this paper established dual porosity media mathematical model of multispecies fluid diffusion and seepage of exploitation coalbed methane by gas injection. The nonlinear mathematical model is investigated by using finite different method and got some valuable conclusions: recovery of methane from coal beds can be improved by injection of carbon dioxide. There are two main mechanisms that aid recovery of the coal beds methane content. Firstly, by reducing the partial pressure of the methane present in the fracture, the diffusion from the coal is enhanced, the second mechanism is the competitive adsorption of carbon into the coal matrix. Molecules of CO2 preferentially absorb on to the surface adsorption sites, displacing methane.
出处
《辽宁工程技术大学学报（自然科学版）》
EI
CAS
北大核心
2005年第3期305-308,共4页
Journal of Liaoning Technical University (Natural Science)
基金
辽宁省博士启动基金资助项目(20041084)
国家自然科学基金重大基金资助项目(50490275)
辽宁省教育厅基金资助项目(20081021)
关键词
煤层气
注气开采
多组分流体
双重介质
扩散
渗流
coalbed methane
exploitation by gas injection
multispecies fluid
dual media
diffusion
seepage
