长期气体作用下焦煤微观孔隙特性研究  

Study on Micro-pores Characteristics of Coking Coal Under Long-term Gas Action

作　　者：牛文星 冯子军[1,2] 杨一凡 万志军[3] NIU Wenxing;FENG Zijun;YANG Yifan;WAN Zhijun(Key Laboratory of In-situ Modified Mining of the Ministry of Education,Taiyuan University of Technology,Taiyuan 030024,China;Department of Mining Engineering,Taiyuan University of Technology,Taiyuan 030024,China;State Key Laboratory of Coal Resources and Safe Mining,China University of Mining and Technology,Xuzhou 221116,China)

机构地区：[1]太原理工大学原位改性采矿教育部重点实验室,山西太原030024 [2]太原理工大学采矿工程系,山西太原030024 [3]中国矿业大学煤炭资源与安全开采国家重点实验室,江苏徐州221116

出　　处：《煤矿安全》2020年第9期47-51,共5页Safety in Coal Mines

基　　金：中国矿业大学煤炭资源与安全开采国家重点实验室开放研究基金资助项目(SKLCRSM18KF015);国家自然科学基金资助项目(U1810104);山西省高等学校创新人才支持计划资助项目。

摘　　要：通过研究煤在长时气体氛围作用下,山西焦煤孔隙结构的演化规律,定性描述了三轴应力及气体吸附后焦煤的孔隙演化特征,为煤层气的开采以及煤矿瓦斯安全从微观方面给出理论依据;焦煤的孔隙结构特征采用高压压汞实验结合扫描电镜SEM的方法,实验测得吸附性气体N2长期作用后山西焦煤试样对比原焦煤试样:孔比表面积提高了27.8%,孔容降低了10.6%;非吸附性气体He长期作用后山西焦煤试样对比原焦煤试样:孔比表面积降低了21.9%,孔容提高了76.6%。结果表明:吸附性气体主要对焦煤孔隙结构中微孔、小孔产生影响;非吸附性气体主要对焦煤孔隙结构中中孔、大孔、可见孔产生影响;吸附性气体的吸附作用在一定程度会降低气体孔隙压对孔隙的扩张作用。By studying the evolution law of coal pore structure under the action of long-term gas atmosphere,this paper qualitatively describes the pore evolution characteristics of coke coal after long-term adsorption of gas,and gives guidance for micro-environmental aspects of coalbed methane mining and coal mine gas safety.The pore structure of coking coal is characterized by high pressure mercury injection test and SEM.After measuring the adsorption gas N2,the Shanxi coking coal sample was compared with the original coking coal sample:the specific surface area of the hole increased by 27.8%;the pore volume decreased by 10.6%.After the non-adsorbing gas He acts,the Shanxi coking coal sample is compared with the original coking coal sample:the specific surface area of the hole is reduced by 21.9%,and the pore volume is increased by 76.6%.The results show that the adsorptive gas mainly affects micro-pores and pores;non-adsorbed gases mainly affect meso-pores,macropores and visible pores.The adsorption of the adsorptive gas will reduce the pore expansion of the pores to a certain extent.

关 键 词：孔隙结构 吸附作用 压汞 孔隙压力 SEM 

分 类 号：TD712[矿业工程—矿井通风与安全]