电极材料对电化学改性无烟煤前后甲烷吸附解吸特性影响的实验研究  

Experimental research on the effects of electrode materials on methane adsorption and desorption in anthracite modified by electrochemical treatment

作　　者：张晓雨 康天合[1] 侯鸣晓 康健婷[1] 郭俊庆[1] 李立功[1] 张润旭 胡耀青[1] ZHANG XiaoYu;KANG TianHe;HOU MingXiao;KANG JianTing;GUO JunQing;LI LiGong;ZHANG RunXu;HU YaoQing(Key Laboratory of In-situ Property-improving Mining of Ministry of Education,Taiyuan University of Technology,Taiyuan 030024,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,太原030024

出　　处：《地球物理学报》2020年第6期2466-2477,共12页Chinese Journal of Geophysics

基　　金：国家自然科学基金项目(U1810102,41902179)资助.

摘　　要：针对电化学作用能够显著增强煤中甲烷解吸渗流特性,但对其电极材料的选择缺乏依据的问题,采用实验的方法研究了铝、铁、铜和石墨四种电极材料对电化学改性无烟煤甲烷吸附解吸特性的影响.结果表明:(1)未改性自然煤样的甲烷饱和吸附量a为39.92mL·g^-1,由铝、铁、铜和石墨四种电极材料进行电化学改性后阳极区域煤样的甲烷饱和吸附量a分别降低了5.22%、8.48%、9.24%和11.33%,阴极区域煤样的甲烷饱和吸附量a分别降低了9.53%、4.97%、6.25%和4.97%;(2)未改性自然煤样在300min的甲烷解吸率为83.17%,经铝、铁、铜和石墨四种电极材料改性后阳极区域煤样的甲烷解吸率分别提高了9.50%、7.10%、8.36%和15.75%,阴极区域煤样的甲烷解吸率分别提高了1.76%、1.12%、6.10%和16.23%;(3)采用石墨作为电极的电化学对无烟煤甲烷解吸的影响效果最为明显,原因在于石墨阳极处电解反应生成较多的H^+离子,一方面对煤表面进行酸化,抑制了煤甲烷的吸附,另一方面更多地溶蚀煤中的碳酸盐和硫酸盐矿物,增加了煤中的孔隙,使得甲烷最终解吸率有所升高.本文的研究结果可为电化学强化煤甲烷解吸电极材料的优选提供基础依据.The electrochemical treatment can significantly enhance the desorption and seepage of the methane in coal beds,but lacking the basis for the selection of electrode materials.To solve this problem,by experiments,this work examined the effects of aluminum,iron,copper and graphite as four electrode materials on the characteristics of methane adsorption and desorption in anthracite modified by electrochemical treatment.The results show that(1)the maximum amount of adsorbed gas aof the unmodified coal sample is 39.920 mL·g^-1,and the value of aof the anode sample after modified by aluminum,iron,copper and graphite decrease by 5.22%,8.48%,9.24%and 11.33%,respectively,and the values of aof the cathode sample decrease by9.53%,4.97%,6.25%and 4.97%,respectively.(2)The gas desorption rate of the unmodified sample at 300 min is 83.17%,while after the electrochemical modification with aluminum,iron,copper and graphite electrode materials,the rate of the gas desorption of anode sample increases by 9.50%,7.10%,8.36%and 15.75%,respectively,the rate of the gas desorption of cathode sample increases by 1.76%,1.12%,6.10% and 16.23%,respectively.(3)The effect of electrochemical treatment with graphite electrode on the gas desorption of anthracite is optimal because the most H^+ ions formed at the graphite anode by electrolysis reaction,the surface of the coal is acidified,and the adsorption of coal gas is inhibited.On the other hand,the carbonate and sulfate minerals in the coal are dissolved and migrated,therefore the final desorption rate of gas increases.The results of this work provide a basis for the optimization of electrode materials with electrochemically enhanced desorption of coal bed methane.

关 键 词：无烟煤 电化学 电极材料 甲烷 吸附解吸 

分 类 号：P631[天文地球—地质矿产勘探]