无烟煤对超临界态CH_(4)-CO_(2)气体吸附特性研究  

Study on adsorption characteristics of anthracite coal to supercritical CH_(4)-CO_(2) gas

作　　者：张明杰 周巍[2] 杨娟 梁锡明 李哲[2] ZHANG Mingjie;ZHOU Wei;YANG Juan;LIANG Ximing;LI Zhe(State Key Laboratory Cultivation Base for Gas Geology and Gas Control,Henan Polytechnic University,Jiaozuo Henan 454003,China;School of Safety Science and Engineering,Henan Polytechnic University,Jiaozuo Henan 454003,China;Collaborative Innovation Center of Coalbed Methane and Shale Gas for Central Plains Economic Region,Jiaozuo Henan 454003,China)

机构地区：[1]河南省瓦斯地质与瓦斯治理重点实验室-省部共建国家重点实验室培育基地,河南焦作454003 [2]河南理工大学安全科学与工程学院,河南焦作454003 [3]中原经济区煤层(页岩)气河南省协同创新中心,河南焦作454003

出　　处：《中国安全生产科学技术》2022年第7期81-87,共7页Journal of Safety Science and Technology

基　　金：国家科技重大专项(2011ZX05040-005);河南理工大学博士基金项目(B2017-04);教育部创新团队计划项目(IRT_16R22)。

摘　　要：为探究无烟煤对超临界态CH_(4)-CO_(2)混合气体的吸附特性,采用重量法开展无烟煤对纯CH_(4)与纯CO_(2)气体、3种体积浓度CH_(4)-CO_(2)混合气样的超临界等温吸附实验,应用过剩吸附理论和Langmuir单层吸附理论,通过校正绝对吸附量、计算吸附相密度、煤的比表面积以及测定吸附平衡后游离态气体组分,探究由亚临界状态到超临界状态下无烟煤吸附纯CH_(4)、纯CO_(2)以及混合气体的吸附相密度变化特征、混合气吸附特征以及吸附分子层数。研究结果表明:煤对纯CH_(4)与纯CO_(2)、混合气体过剩吸附量随着压力增大呈现出先增大后减小的峰值型曲线;CH_(4)绝对吸附量随吸附压力增大不断增大,接近CH_(4)临界压力时,绝对吸附量缓慢增加并趋于稳定。低压下CH_(4)在煤颗粒中以单层吸附为主;超过临界压力后出现表面局部2层吸附的现象;1~3 MPa时,CO_(2)在煤颗粒中即表现出2层吸附为主的现象,随压力增大甚至出现局部4层吸附的现象,煤颗粒对CO_(2)有更大的吸附能力。In order to explore the adsorption characteristics of anthracite to the supercritical CH_(4)-CO_(2) mixed gas,the supercritical isotherm adsorption experiments of anthracite on the pure CH_(4) gas,pure CO_(2) gas and CH_(4)-CO_(2) mixed gas samples with three volume concentrations were carried out by the gravimetric method.The excess adsorption theory and Langmuir monolayer adsorption theory were applied,and the variation characteristics of adsorption phase density,the adsorption characteristics of mixed gas and the number of adsorbed molecular layers of anthracite adsorption on the pure CH_(4),pure CO_(2) and mixed gas from subcritical state to supercritical state were explored by correcting the absolute adsorption amount,calculating the adsorption phase density and the specific surface area of coal,and determining the free gas composition after adsorption equilibrium.The results showed that the excess adsorption amount of pure CH_(4),pure CO_(2) and mixed gas by coal presented a peak curve that increased first and then decreased with the pressure.The absolute adsorption amount of CH_(4) increased with the increase of adsorption pressure,and it increased slowly and tended to be stable near the critical pressure of CH_(4).Under low pressure,CH_(4) was mainly adsorbed in a single layer in the coal particles,and there would be the two-layer adsorption on the surface after exceeding the critical pressure.At 1~3 MPa,CO_(2) was mainly adsorbed in two layers in the coal particles,and the phenomenon of local 4-layer adsorption even appeared with the increase of pressure,so the coal particles had a greater adsorption capacity for CO_(2).

关 键 词：超临界态 煤的吸附特征 重量法 二元气体吸附 

分 类 号：X936[环境科学与工程—安全科学]