煤体变形对气体等温吸附量计算影响及模型优化  

Influence of coal deformation on calculation of gas isothermal adsorption capacity and model optimization

作　　者：张遵国 唐朝 陈毅 张春华 张宏虎[1] 袁新立 ZHANG Zunguo;TANG Chao;CHEN Yi;ZHANG Chunhua;ZHANG Honghu;YUAN Xinli(College of Safety Science and Engineering,Liaoning Technical University,Huludao,Liaoning 125105,China;Key Laboratory of Mine Thermo-motive Disaster&Prevention,Ministry of Education,Huludao,Liaoning 125105,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125105 [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125105

出　　处：《中国矿业大学学报》2023年第3期513-526,共14页Journal of China University of Mining & Technology

基　　金：国家自然科学基金项目(51704147,51974149);辽宁省教育厅高等学校基本科研项目(LJKZ0345)。

摘　　要：为研究煤体变形对CO_(2)吸附量计算的影响,开展了原煤在He和CO_(2)气氛下的等温吸附/解吸试验,同步测试了煤样应变,分析了煤样在2种气氛下的吸附/解吸及变形特征,探讨了He升压和降压过程样品罐自由空间体积与气体压力的关系,建立了绝对吸附量的精确计算模型.结果表明:在He气氛下煤样产生压缩变形,应变与平衡压力关系曲线可以划分为Ⅰ~Ⅱ2种类型,Ⅰ类曲线升压过程和降压过程均具有2个变形阶段;Ⅱ类曲线升压过程和降压过程均仅具有1个变形阶段.在CO_(2)气氛下,煤样吸附气体产生膨胀变形,1/3焦煤和贫煤最大体应变分别为1.72%和1.63%;等温解吸过程,煤样解吸应变存在超前和滞后2种现象,且完全解吸后存在富余变形.随气体压力增大,1/3焦煤样品罐自由空间体积先减小后增大至趋于稳定,表现出明显的“减”—“增”2个阶段;贫煤样品罐自由空间体积始终随气体压力的增大而增大;随气体压力降低,1/3焦煤和贫煤样品罐自由空间体积均表现为缓慢增大和快速增大2个阶段.提出了能有效消除He气氛下煤样受气体压缩变形导致吸附量计算误差的方法.综合考虑煤吸附/解吸过程气体压力作用引起的压缩变形、吸附膨胀变形及吸附相体积对吸附量计算的影响,建立了绝对吸附量计算模型,可以准确计算煤样等温吸附/解吸过程中的绝对吸附量.In order to study the influence of coal deformation on the calculation of CO_(2) adsorption capacity,the isothermal adsorption/desorption experiment of raw coals under He and CO_(2) atmosphere were carried out,and the strain of coal samples was tested simultaneously during adsorption/desorption process.The adsorption/desorption and deformation characteristics of coal samples under two atmospheres were analyzed.The relationship between the free space volume of the sample tank and the gas pressure in the process of He boost and depressor was discussed.And the exact calculation model of the absolute adsorption capacity of coal was established.The results show that compressive deformation occurs in coal samples under He atmosphere,and the relationship curve between strain and equilibrium pressure can be divided into two types:I-II.There are two deformation stages of class I curves while the class II curves only show one deformation stage in the boosting process and depressurization process of pressure.Under the COz atmosphere,the coal samples adsorbed gas cause expansion deformation,the maximum volumetric strain of 1/3 coking coals and lean coals increased 1.72%and 1.63%respectively.The strain presents advance and hysteresis two phenomena during the isothermal desorption process,and there is redundant deformation after complete desorption.With the increase of gas pressure,the free space volume of sample tank on 1/3 coking coal first decreases and then increases to be stable,showing two distinct stages of"decreasing"and"increasing",while the lean coal always increases with the increase of gas pressure.With the decrease of gas pressure,the free space volume of sample tank on 1/3 coking coal and lean coal both shows rapid growing stage and slow growing stage.A method is proposed to effectively eliminate the calculation error of adsorption capacity caused by gas compression deformation of coal samples in He atmosphere.Comprehensively considering the effects of compression deformation,adsorption expansion deformation and

关 键 词：压缩变形 自由空间体积 吸附膨胀 绝对吸附量 计算模型 

分 类 号：TD712[矿业工程—矿井通风与安全]