摘要
为对比研究页岩和煤在CO_2作用下吸附解吸与变形特性,采用四川盆地龙马溪组页岩和塔山煤矿煤样,利用"高温高压页岩吸附膨胀仪"在0~16 MPa CO_2压力下对以上两类样品进行了长达2 000 h的等温吸附及变形试验。结果表明:在渗透率和CO_2密度共同影响下,页岩和煤吸附平衡时间在0~6 MPa内随平衡压力升高逐渐增加;当CO_2压力到达临界压力附近时,吸附平衡时间急剧缩短(页岩9.3 h,煤4.8 h);继续升高平衡压力,平衡时间再次增加。垂直、平行层理方向弹性模量的差异致使页岩变形各向异性随平衡压力升高不断减弱;煤变形各向异性比页岩更显著,随平衡压力升高波动性较大。页岩在气体压力为10 MPa附近达最大吸附量0.082 mmol/g,其体积应变量与吸附量满足二次函数关系。煤在气体压力为7 MPa附近达最大吸附量1.421 mmol/g,其体积应变量与吸附量呈现良好的线性关系。
To investigate the adsorption and deformation characteristics of shale and coal under CO2,two kinds of samples including shale in Longmaxi Formation and coal in Tashan mine were collected to conduct a 2 000 hours isothermal adsorption test which was operated at 0-16 MPa CO2 pressure by ＂shale adsorption and expansion instrument under high temperature and high pressure＂. The results showed that under the combined influence of permeability and CO2 density,the adsorption equilibrium time of shale and coal increased gradually at first,then decreased sharply to the bottom（ shale 9.3 h,coal 4.8 h） when CO2 pressure reached the critical level,finally raised again.The deformation anisotropy of shale decreases with the increase of pressure which is caused by the different elastic modulus.While the isothermal adsorption curves of shale and coal are similar,and have the maximum adsorption capacity of0. 082 mmol/g and 1. 421 mmol/g respectively in the vicinity of 10 MPa and 7 MPa.It was found that the deformation characteristics of shale and coal are obviously different： the volumetric strain and the adsorption capacity modelled an appropriate quadratic function on shale,but fitted a good linear relationship on coal.
作者
汤积仁
王相成
卢义玉
敖翔
韩帅彬
TANG Jlren;WANG Xiangcheng;LU Yiyu;AO Xiang;HAN Shuaibin(State Key Laboratory of Coal Mine Disaster Dynamics and Control,Chongqing University,Chongqing 400030,China;National ＆ Local of Gas Drainage in Complex Coal Seam,Chongqing University,Chongqing 400030,China)
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2018年第8期2288-2295,共8页
Journal of China Coal Society
基金
国家自然科学基金青年基金资助项目(51404045)
国家重点基础研究发展计划(973)资助项目(2014CB239206)
长江学者和创新团队发展计划资助项目(IRT17R112)
关键词
CO2强化开采技术
煤-岩对比
时间效应
吸附变形
变形各向异性
CO2 enhanced mining technology
comparison of shale and coal
time effect
adsorption and deformation
deformation anisotropy
