摘要
干酪根对甲烷和二氧化碳的吸附行为对页岩气的开采有着重要的意义。根据有机质结构特点,构建三维干酪根模型,采用巨正则系综蒙特卡洛(GCMC)方法和分子动力学方法(MD)研究CH_4和CO_2的气体竞争吸附行为。结果表明:1 CH_4和CO_2单组分吸附时吸附量随着压力的增大会增大,CO_2吸附会在较小的压力达到饱和。两种气体吸附符合Langmuir吸附规律,可以使用Langmuir方程进行拟合;2 CO_2和CH_4在干酪根中的吸附热均随着各自的吸附量先减小后在增大;3在相同的压力下,吸附选择性随着温度的升高而减小。在同一温度下,低压阶段,吸附选择性随着压力的升高而减小。由选择性数值看出,CO_2更易被干酪根吸附。
The CH4 and CO2adsorption behavior in kerogen for exploitation of shale gas has important significance. The kerogen molecular model was construct to study the adsorption behaviour of CH4 and CO2different pressures using the Monte Carlo and Molecular Dynamic methods. The results show： 1 The adsorption amount of CH4 and CO2increases with pressure increase and CO2 adsorption amount will reach maximum at small pressure. The adsorption of CH4 and CO2accorded with the law of Langmuir adsorption and can be fit by Langmuir equation. 2The isosteric adsorption heat of CH4 or CO2adsorbed in kerogen will first decrease and than increase as the adsorption amount increase. 3 CO2/ CH4 adsorption selectivity decreases as temperature increase at a fixed pressure,and in low pressure,the adsorption selectivity decreases as the pressure increase at a fixed temperaure.
出处
《科学技术与工程》
北大核心
2016年第11期128-131,135,共5页
Science Technology and Engineering
基金
国家自然科学基金(51234007
51490654
51504276)
长江学者和创新团队发展计划(IRT1294)资助
关键词
甲烷
二氧化碳
干酪根
竞争吸附
分子模拟
CH4
CO2
kerogen
competitive adsorption
molecular simulation
