Investigation of the preferential adsorption/desorption behavior of N2, CH4 and CO2 on coal
Adsorption experiments for single-component gases (CO2, CH4 and N2) and adsorption/desorption experiments for dual-component gases (80% CO2+20% CH4, 20% CO2+80% CH4, 50% CO2 + 50% N2) were carried out to study the preferential adsorption/desorption behavior of CH4/CO2 and CH4/N2 mixtures on a high volatile bituminous coal. During the experiments, free gas composition variation in the adsorption/desorption processes was measured by gas chromatography. The results shows that for the same coal, the single-component gas adsorption capacity is CO2 >CH4 >N2.For the investigated dual-component gases (CO2/CH4), the coal is preferentially adsorptive to CO2, but is preferentially desorptive to CH4. The extent of the preferential adsorption/desorption is stronger in the 80% CO2 +20% CH4 than in the 20% CO+ 80% CH4 components. The behavior of CH4 displacement with CO2 was observed during the processes of adsorption/desorption of dual-component gases. It is concluded that the efficiency of displacing CH4 by CO2 relates to not only the gas adsorption capacity itself, but also to the partition pressure proportion of CO2 in the free phase components: higher proportion of CO2 induces much better displacement effect. The experiment study could be used to predict the displacement efficiency and to evaluate whether the injected CO2 volume is enough in the in-situ CO2-ECBM.
coal adsorption/desorption enhanced coalbed methane recovery (ECBM) CO2 sequestration
Y. B. Yao D. M. Liu Y. M. Gao
School of Energy Resources, China University of Geosciences, Beijing, 100083, China
国际会议
徐州
英文
239-247
2009-09-24（万方平台首次上网日期，不代表论文的发表时间）