采空区遗煤吸附电厂烟气中CO_(2)影响因素研究  

Study on the factors affecting the adsorption of CO_(2) from power plant flus gas in coal left in goaf area

作　　者：高飞[1,2] 王鹏 单亚飞[1] GAO Fei;WANG Peng;SHAN Yafei(School of Safety Science and Engineering,Liaoning Technical University,Huludao 125100,China;Key Laboratory of Mine Thermodynamic Disasters and Control of Ministry of Education,Liaoning Technical University,Huludao 125100,China)

机构地区：[1]辽宁工程技术大学安全科学与工程学院,辽宁葫芦岛125100 [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,辽宁葫芦岛125100

出　　处：《煤炭科学技术》2023年第9期140-148,共9页Coal Science and Technology

基　　金：国家自然基金面上资助项目(51874161)。

摘　　要：利用采空区煤岩的吸附特性封存CO_(2),不仅可以降低碳捕集与分离成本,还能实现防治采空区遗煤自燃的目的。采用常温常压吸附试验、ASAP比表面积和孔径分析试验,探究了孔隙结构、矿物质含量和含水率对煤吸附CO_(2)特性的影响,拟合了影响煤吸附CO_(2)因素的定量关系方程,并通过随机森林算法计算了各影响因素的重要性权重。结果表明:大南湖(DNH)矿、鹤岗(HG)矿、同忻(TX)矿区3种煤的孔径分布规律基本一致,孔径范围在0.5~0.7 nm和0.8~0.9 nm内的孔数量较多,在0.7~0.8 nm的孔数量较少;微孔数量是导致3种煤对CO_(2)吸附能力差异的根本原因。常温常压条件下,煤对CO_(2)的饱和吸附量随比表面积的增加而增大,随矿物质含量和含水率的增加而减小,且煤的微孔数量越多,矿物质含量和含水率对吸附量的影响越显著。煤在达到临界含水率后,由于水分子阻碍了CO_(2)分子的流通通道,导致CO_(2)分子无法进入煤内部的孔隙中,CO_(2)饱和吸附量逐渐趋于稳定。比表面积对吸附量的影响程度最大,含水率与孔体积次之,矿物质含量最弱,且比表面积与含水率的重要性权重之和可达75.1%,远高于其他两个因素。依据拟合方程,可通过测定煤的比表面积、矿物质含量和含水率,推测煤对CO_(2)的饱和吸附量,为采空区遗煤吸附封存CO_(2)提供理论依据。Utilizing the adsorption characteristics of coal rock in the goaf to storage CO_(2) not only reduces the cost of carbon capture and separation,but also prevents spontaneous combustion of coal left in goaf area.The effects of pore structure,mineral content and moisture content on the CO_(2) adsorption characteristics of coal were investigated using adsorption experiments at ambient temperature and pressure,ASAP specific surface area and pore size analysis experiments.Then the quantitative relationship equations of factors affecting CO_(2) adsorption in coal were fitted,and the importance weights of each influence was calculated by Random Forest algorithm.The results shown that,the pore size distribution of three coals from the mining area of Dananhu(DNH),Hegang(HG)and Tongxin(TX)were basically the same.The number of pores in the range of 0.5-0.7 nm and 0.8-0.9 nm was more,and that in the range of 0.7-0.8 nm was less.The number of micropores was the fundamental reason for the difference in CO_(2) adsorption capacity of three coals.At ambient temperature and pressure,the saturated adsorption amount of CO_(2) in coal increased with the increasing specific surface area,and decreased with the increasing mineral content and moisture content.The more the number of micropores of coal,the more significant the influence of mineral content and moisture content on the adsorption amount.After the coal reached the critical moisture content,the saturated CO_(2) adsorption amount gradually tended to be stable because the water molecules hindered the flow channels of CO_(2) molecules,resulting in the CO_(2) molecules not being able to enter into the pores inside the coal.The specific surface area had the greatest influence on the adsorption amount,followed by the moisture content and pore volume,and the mineral content was the weakest.Specific surface area and moisture content had a com-bined importance weight of 75.1%,which was much higher than the other two factors.According to the fitting equation,the saturated ad-sorption amou

关 键 词：采空区 遗煤 电厂烟气 碳捕集、利用与封存(CCUS) 孔隙结构 

分 类 号：TD849[矿业工程—煤矿开采] X773[矿业工程—矿山开采]