1. College of Mining Engineering,Taiyuan University of Technology,Taiyuan　 030024,China; 2. Key Laboratory of In-situ Prooperty-improving Under Min-ing of Ministry of Education,Taiyuan University of Technology,Taiyuan　 030024,China 3. University of Waterloo,Civil and Environmental Engineering,Wa-terloo　 N2L3G1

利用自主研发的气体等温吸附装置并辅以TST3827动静态应变测试系统,针对4种不同煤阶的煤样试件,在恒定温度（50℃）不同吸附压力条件下,研究了不同煤阶煤样CO2吸附特性及煤样的吸附变形规律。结果表明:煤体CO2吸附量与煤阶密切相关,在相同的吸附压力条件下,CO2吸附量随着煤阶的增大而增大;不同煤阶煤样的等温吸附曲线类似,煤样的CO2过剩吸附量随吸附压力变化曲线呈现出先升高后降低的特点,在8 MPa左右达到最大值;不同煤阶煤体吸附CO2后引起的变形也具有类似的变化趋势,即随着CO2压力的增大,体积应变先增大后趋于稳定,体积应变可以用引入CO2密度的DR模型进行描述,且随着煤阶的增大,体积应变逐渐减小;由于煤体层理结构特征,煤体在垂直于层理方向的应变约为平行于层理方向应变的1.82.3倍;煤体体积应变与绝对吸附量在气态CO2中呈线性增长关系,当CO2达到超临界状态以后随着绝对吸附量增加体积应变趋于稳定,且煤体吸附相同量CO2产生的体积应变随煤阶的增大而减小。

Based on the gas isothermal adsorption device developed by ourselves and the TST3 827 dynamic and static strain test system,the isothermal adsorption test of CO2 was carried out under different adsorption pressure conditions at constant temperature (50 ℃ ) for four different coal samples to study the adsorption capacity of different coal rank samples in CO2 and the swelling caused by adsorption. The results show that the adsorption capacity of CO2 is closely related to the coal rank. Under the same adsorption pressure,the adsorption capacity of CO2 increases with the increase of coal rank. The isothermal adsorption curves of different coal rank samples are similar,and the excess adsorption ca- pacity of coal samples increases first and then decreases with the adsorption pressure,and reaches the maximum at a- bout 8 MPa. The deformation of the different rank coal due to adsorption in CO2 also has a similar trend,that is,with the increase of CO2 pressure,the volume strain increases first and then tends to be stable,and the volume strain can be Based on the gas isothermal adsorption device developed by ourselves and the TST3 827 dynamic and static strain test system,the isothermal adsorption test of CO2 was carried out under different adsorption pressure conditions at constant temperature (50 ℃ ) for four different coal samples to study the adsorption capacity of different coal rank samples in CO2 and the swelling caused by adsorption. The results show that the adsorption capacity of CO2 is closely related to the coal rank. Under the same adsorption pressure,the adsorption capacity of CO2 increases with the increase of coal rank. The isothermal adsorption curves of different coal rank samples are similar,and the excess adsorption ca- pacity of coal samples increases first and then decreases with the adsorption pressure,and reaches the maximum at a- bout 8 MPa. The deformation of the different rank coal due to adsorption in CO2 also has a similar trend,that is,with the increase of CO2 pressure,the volume strain increases first and then tends to be stable,and the volume strain can be

HE Wei,LIANG Weiguo,ZHANG Beining,et al. Experimental study on swelling characteristics of CO2 adsorption and storage in different coal rank[J]. Journal of China Coal Society,2018,43(5):1408-1415.