不同煤阶煤样对酸性气体吸附机理研究  

Research on the adsorption mechanism of acid gases for coal samples of different coal ranks

作　　者：王岩 WANG Yan(CCTEG Shenyang Research Institute,Fushun,Liaoning 113122,China;State Key Laboratory of Coal Mine Safety Technology,Fushun,Liaoning 113122,China)

机构地区：[1]中煤科工集团沈阳研究院有限公司,辽宁省抚顺市113122 [2]煤矿安全技术国家重点实验室,辽宁省抚顺市113122

出　　处：《中国煤炭》2024年第10期142-149,共8页China Coal

摘　　要：为明确煤基吸附剂对酸性气体的吸附机理以及煤变质作用对吸附过程的影响,基于巨正则系蒙特卡洛计算方法,从分子动力学和热力学角度,研究了吸附体系的吸附量、吸附热力学参数(吸附热、吸附势、吸附熵)和相对浓度分布。研究发现,H_(2)S、SO_(2)、Cl_(2)、CO_(2)这4种酸性气体的吸附规律均符合弗雷德利希(Freundlich)吸附模型,无烟煤的Freundlich吸附常数x最小,表明无烟煤中存在更多的吸附位点,相比其他煤样更容易吸附酸性气体,无烟煤对4种酸性气体的吸附量大小依次为H_(2)S>SO_(2)>Cl_(2)>CO_(2);高阶煤表面存在强的各向异性,使得无烟煤体系产生的吸附热高于烟煤和褐煤,4种气体的平均吸附热大小依次为H_(2)S>SO_(2)>Cl_(2)>CO_(2),从热力学角度也证明了H_(2)S更易占据同煤阶煤样的有效吸附位点;4种酸性气体在烟煤中的相对浓度分布呈现明显的聚集情况,H_(2)S的相对浓度波动范围小于SO_(2)、CO_(2)和Cl_(2),说明H_(2)S的分布更为均匀,可以占据煤表面更多的吸附位点。In order to clarify the adsorption mechanism of coal-based adsorbents on acid gases and the influence of coal metamorphism on the adsorption process,the adsorption quantity,adsorption thermodynamic parameters(i.e.adsorption heat,adsorption potential,and adsorption entropy),and the relative concentration distribution of adsorption system were investigated in terms of molecular dynamics and thermodynamics based on the Monte Carlo calculation method for giant canonical system.It was found that the adsorption patterns of the four acid gases(i.e.H_(2)S,SO_(2),Cl_(2),CO_(2))were in accordance with the Freundlich adsorption model,and the Freundlich adsorption constant(x)of anthracite was the smallest,which indicated that more adsorption sites existed in anthracite,and it was easier to adsorb acid gases for anthracite compared with the other coal samples,and the order of adsorption quantity of the four acid gases by anthracite from high to low was H_(2)S>SO_(2)>Cl_(2)>CO_(2);the strong anisotropy on the surface of high-rank coals made the adsorption heat generated by the anthracite system higher than that of bituminous coal and lignite,and the order of average adsorption heat of the four gases from high to low was H_(2)S>SO_(2)>Cl_(2)>CO_(2),which also proved that it was easier for H_(2)S to occupy effective adsorption sites in the same rank coal samples from the thermodynamic view;the relative concentration distributions of the four acid gases in bituminous coal showed obvious aggregation,and the fluctuation range of the relative concentration of H_(2)S was smaller than that of SO_(2),CO_(2)and Cl_(2),indicating that the distribution of H_(2)S was more homogeneous,which could occupy more adsorption sites on the coal surface.

关 键 词：酸性气体 煤阶煤样 分子模拟 吸附热 相对浓度分布 

分 类 号：TD752.2[矿业工程—矿井通风与安全]