基于核磁共振技术不同煤样吸附CH4实验研究  

Experimental research on CH4 adsorption of different coal samples based on NMR technology

作　　者：韩光[1,2] 李东芳 常利强 周西华[1,2] 白刚[1,2] HAN Guang;LI Dongfang;CHANG Liqiang;ZHOU Xihua;BAI Gang(College of Safety Science and Engineering,Liaoning Technical University,Fuxin Liaoning 123000,China;Key Laboratory of Mine Thermodynamic Disasters and Control of Ministry of Education,Liaoning Technical University,Fuxin Liaoning 123000,China;Tianjin Design Engineering Chinacoal Co.,Ltd.,Tianjin 300000,China)

机构地区：[1]辽宁工程技术大学安全科学与工程学院,辽宁阜新123000 [2]辽宁工程技术大学矿山热动力灾害与防治教育部重点实验室,辽宁阜新123000 [3]中煤天津设计工程有限责任公司,天津300000

出　　处：《中国安全生产科学技术》2021年第1期143-148,共6页Journal of Safety Science and Technology

基　　金：辽宁省教育厅重点项目(LJCL001)。

摘　　要：为研究CH4在高、中、低阶3种煤样(无烟煤、焦煤、长焰煤)中的吸附特性及分布规律,采用低场核磁共振技术在不同吸附时间、不同压力条件下分别进行不同煤样的吸附甲烷实验。从微观上分析时间效应、变质效应、压力效应对煤吸附CH4的影响规律及甲烷在煤上各个孔径阶段分布变化。结果表明:随着吸附时间的增大,3种煤样的吸附态T2谱振幅积分均增加,大小依次为无烟煤>焦煤>长焰煤,吸附速率呈先快后慢的趋势,而游离态的T2谱振幅积分和区间范围逐步减少;随着注气压力的增加,3种煤样的吸附态和游离态的T2谱振幅积分和区间范围逐渐增大,吸附态T2谱积分曲线符合等温吸附方程,游离态T2谱积分曲线与压力呈正相关;吸附态甲烷主要集中在微小孔中,游离态甲烷主要集中在大孔和裂隙中。In order to study the adsorption characteristics and distribution of CH4 in three coal samples of high,medium and low rank(anthracite,coking coal,and long flame coal),the low-field nuclear magnetic resonance(NMR)technology was used to conduct experiments on the CH4 adsorption of different coal samples under different adsorption time and pressure conditions.The influence of time effect,metamorphism effect and pressure effect on the CH4 adsorption of coal and the distribution change of CH4 in each pore size stage were analyzed from the microscopic view.The results showed that with the increase of adsorption time,the amplitude integration of the adsorbed state T2 spectrum of the three coal samples increased,the order was anthracite>coking coal>long flame coal,and the adsorption rate presented the trend of fast first and then slow,while the amplitude integration and interval range of free state T2 spectrum gradually decreased.With the increase of gas injection pressure,the amplitude integration and interval range of the adsorbed state and free state T2 spectrum for the three coal samples increased gradually.The integration curve of adsorbed state T2 spectrum conformed to the isothermal adsorption equation,and the integration curve of free state T2 spectrum was positively correlated with pressure.The adsorbed methane was mainly in the micro pores,and the free methane was concentrated in the large pores and fissures.

关 键 词：核磁共振T2谱 吸附态甲烷 游离态甲烷 孔径分布 不同煤样 

分 类 号：X936[环境科学与工程—安全科学]