构造煤微观结构对其吸附特性的影响实验  

Experiment on the influence of microstructure of tectonic coal on its adsorption characteristics

作　　者：肖鹏 杜媛媛[1,2] XIAO Peng;DU Yuanyuan(College of Safety Science and Engineering,Xi’an University of Science and Technology,Xi’an 710054,China;Key Laboratory of Western Mine Exploitation and Hazard Prevention,Ministry of Education,Xi’an University of Science and Technology,Xi’an 710054,China)

机构地区：[1]西安科技大学安全科学与工程学院,陕西西安710054 [2]西安科技大学西部矿井开采及灾害防治教育部重点实验室,陕西西安710054

出　　处：《西安科技大学学报》2021年第2期237-245,共9页Journal of Xi’an University of Science and Technology

基　　金：国家自然科学基金项目(51774235,52074216);陕西省自然科学基础研究计划(2020JM-530)。

摘　　要：为研究构造煤孔隙微观结构及其对瓦斯吸附的影响,采用压汞实验及PCT高压吸附实验,针对澄合矿区典型构造煤煤样进行孔隙结构分析及吸附特性测定,通过实验数据计算煤样孔隙体积及表面分形维数,分析构造煤微观孔隙结构对瓦斯吸附特性及吸附常数a、b值的影响。研究结果表明:煤样总孔容以大孔贡献为主,总比表面积微孔占比最高,各煤样间大、中、小及微孔占比基本相近,煤样坚固性系数与其总孔容成反比;吸附常数a与煤样微孔孔容、比表面积呈正相关关系,吸附常数b随着煤样大孔孔容占比、微孔占比的增大而增加;随着总比表面积增加,单位质量煤瓦斯吸附量逐渐增加,即微孔比表面积越大,瓦斯吸附能力越强;煤样孔隙体积及表面分形维数均可分为两部分,大、中孔隙分形维数在2~3之间,该段分形特征较为明显且孔隙结构复杂,孔隙体积分形维数与吸附常数a呈正相关关系。In order to study the pore microstructure of tectonic coal and its influence on gas adsorption,mercury injection experiment and PCT high-pressure adsorption experiment were adopted to analyze the pore structure and adsorption characteristics of typical tectonic coal samples in Chenghe mining area.Based on the experimental data,the pore volume and surface fractal dimension of coal samples were calculated,and the influence of micro pore structure of tectonic coal on gas adsorption characteristics and adsorption constants A and B was analyzed.The results show that:the total pore volume of coal sample is mainly contributed by macropore,the proportion of micropore in total specific surface area is the highest,the proportion of large,medium,small and micropore among coal samples is basically similar,and the firmness coefficient of coal sample is inversely proportional to its total pore volume;the adsorption constant a is correlated positively with the micropore volume and specific surface area of coal sample,and the adsorption constant b increases with the increase of the proportion of macropore volume and micropore with the increase of the total specific surface area,the gas adsorption capacity per unit mass of coal increases gradually,that is,the larger the specific surface area of micropores,the stronger the gas adsorption capacity;the pore volume and surface fractal dimension of coal samples can be divided into two parts,the fractal dimension of large and medium pores is between 2 and 3,and the fractal characteristics of this section are more obvious and the pore structure is complex,and the fractal dimension of pore volume is correlated positively with the adsorption constant a.

关 键 词：构造煤 压汞 PCT高压吸附 吸附常数 分形维数 

分 类 号：TD712[矿业工程—矿井通风与安全]