CH_4与N_2,CO_2间竞争吸附关系的核磁共振实验研究  

Experimental study on competitive adsorption relationship between CH_4 and N_2,CO_2 by NMR

作　　者：罗明坤[1] 李胜[1,2,3] 荣海[1] 范超军[1] 杨振华[1] LUO Mingkun;LI Sheng;RONG Hai;FAN Chaojun;YANG Zhenhua(College of Mining,Liaoning Technical University, Fuxin 123000, China;State and Local Joint Engineering Laboratory for Gas Drainage ＆ Ground Control of Deep Mines,Henan Polytechnic University, Jiaozuo 454003, China;Research Center of Coal Resources Safe Mining and Clean Utilization, Liaon- ing Technical University, Fuxin 123000, China)

机构地区：[1]辽宁工程技术大学矿业学院,辽宁阜新123000 [2]河南理工大学深井瓦斯抽采与围岩控制技术国家地方联合工程实验室,河南焦作454003 [3]辽宁工程技术大学煤炭资源安全开采与洁净利用工程研究中心,辽宁阜新123000

出　　处：《煤炭学报》2018年第2期490-497,共8页Journal of China Coal Society

基　　金：国家自然科学基金资助项目(51674132);深井瓦斯抽采与围岩控制技术国家地方联合工程实验室开放基金资助项目(G201602)

摘　　要：利用核磁共振(NMR)技术测试了CH_4与CO_2,N_2在煤样中相互作用过程的NMR信号,并通过T_2谱形态和谱面积对各气体间相互作用的整个过程进行了描述和分析。测试结果表明:CH_4在煤中吸附过程的T_2谱呈双峰结构,弛豫时间较小的为吸附峰,另一个为游离峰。随着吸附时间和注入压力的增加,吸附总量逐渐增加,但吸附速率逐渐降低。强吸附性气体能置换煤中已吸附的弱吸附性气体,反之效果不明显;置换过程中,大孔隙内的气体比小孔隙内的更容易置换。将弱吸附性气体注入已吸附强吸附性气体的煤中,一定程度上能促使原气体由吸附态向游离态转化;同时,少量的弱吸附性气体也能被吸附,气压越大越明显。NMR测试结果直观反映了CH_4与各气体间的相互作用关系。Nuclear magnetic resonance（ NMR） technique is used to characterize the different states of CH4 in coal. By testing the NMR signal of interaction between CH4 and CO2 and N2 in coal samples,the whole process of the interaction between each gas are described and analyzed by the T2 spectrum morphology and spectral area. The test results show that the T2 spectrum of CH4 adsorption process in coal is double peaks structure,and the smaller relaxation time is the adsorption peak and the other is free peak. With the increase of adsorption time and injection pressure,the total amount of adsorption increased gradually,but the adsorption rate decreased. Strong adsorption gas can displace the weakly adsorbed gas adsorbed in coal,but on the contrary,the effect is not obvious. In the replacement process,the gas in the macropores is easier to replace than the small pores. When the weakly adsorbed gas is injected into the coal,which has been adsorbed strongly adsorbed gas,the primary gas can be transformed from the adsorbed state to the free state. At the same time,a small amount of weakly adsorbed gas can also be adsorbed,and the greater the pressure,the more obvious. The results of NMR test have directly reflected the interaction between CH4 and other gas.

关 键 词：核磁共振 吸附解吸 置换作用 增产措施 

分 类 号：TD712[矿业工程—矿井通风与安全]