摘要
选择山东菜园矿的气煤和山西古交矿的焦煤的平衡水煤样对不同浓度的CH4和CO2混合气体进行了吸附-解吸实验,分析了CH4和CO2在吸附-解吸过程中各组分浓度的变化规律,并探讨分析了实验过程中出现高压阶段吸附量小于低压时的原因.结果表明,不同浓度的CH4和CO2混合气体的解吸曲线都滞后于吸附曲线;相同条件下,焦煤的吸附量大于气煤的吸附量;CO2与CH4浓度之比越大,气体的吸附量越大;吸附过程中,CO2组分的吸附速率是先快后慢,而CH4组分的吸附速率先慢后快,解吸时则相反.吸附和解吸平衡时,游离相中的CO2浓度低于原始混合气体中的CO2浓度,CH4浓度高于原始气体中CH4浓度.实验结果证实了CO2在与CH4的竞争吸附中占据优势,注入CO2可以有效地置换或驱替煤层CH4,注入CO2气体的数量越大、相对浓度越高,单位压差CH4解吸率和CO2吸附率就越高.
The adsorption-desorption experiment on binary-component gas was carried out with equilibrium water coal sample in gas coal and coking coal. The variation regularity of each component and the reasons of the adsorption in high-pressure stage was less than that in low-pressure in the experiment were analyzed. The results indicate that desorption curve lags the adsorption curve in different concentration of the mixed gases. The adsorption of co- king coal is more than that of gas coal under the same condition and the adsorption gets bigger with the increased concentration ration of CO2/CH4. The adsorption velocity of CO2 is fast at first and then become slow while the contrary phenomenon exist in CH4, and the reverse results are found in desorption stage. When the adsorption-desorption reached the balance, the concentration of CO2 is lower and CH4 is higher than the original conditions. The results also demonstrate that CO2 occupies the predominant position and CO2 -injection can displace CH4. If the con- centration of injected CO2 is great, the rate of CH4 desorption and CO2 adsorption would be high.
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2009年第4期551-555,共5页
Journal of China Coal Society
基金
国家重点基础研究发展计划(973)基金资助项目(2006CB202204)
国家自然科学基金资助项目(40602017)
关键词
煤层气
二元混合气体
吸附-解吸
CO2置换
采收率
coalbed methane
binary-component gas
adsorption-desorption
replacement of methane by carbon dioxide
recovery
