白云质岩石的孔结构与去白云化反应  

Pore structure of dolomitic rocks and dedolomitization

作　　者：刘光辉 陈碧 李伟[1] 茆忠阳 邓敏[1,2] LIU Guanghui;CHEN Bi;LI Wei;MAO Zhongyang;DENG Min(College of Materials Science and Engineering,Nanjing Tech University,Nanjing 211800,China;Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM),Nanjing 211800,China)

机构地区：[1]南京工业大学材料科学与工程学院,江苏南京211800 [2]江苏先进生物与化学制造协同创新中心,江苏南京211800

出　　处：《南京工业大学学报（自然科学版）》2020年第1期34-40,共7页Journal of Nanjing Tech University(Natural Science Edition)

基　　金：江苏省普通高校研究生科研创新计划(KYLX15_0781)

摘　　要：采用压汞法(MIP)和N 2吸附法表征14种白云质岩石的孔结构,采用偏光显微镜和扫描电子显微镜(SEM)分析岩相特征。结果表明:白云质岩石的孔主要是介孔,含有少量的大孔。白云岩和白云质灰岩的最可几孔径为2~4 nm,而泥质白云质岩石无最可几孔径;白云岩中白云石晶粒越小,BET模型计算的孔隙率(2~200 nm)越大;白云质灰岩中方解石晶粒越小,孔隙率(2~200 nm)越大,小孔的孔隙占比越大;泥质白云质岩石中酸不溶物(AIR)的含量越多,孔隙率(2~200 nm)越大;小孔的孔隙占比越大。去白云化反应增加了岩石的孔隙率(2~200 nm)和平均孔直径,而孔结构对去白云化反应没有明显影响。The pore structure of 14 dolomitic rocks was analyzed by mercury intrusion porosimetry(MIP)and nitrogen adsorption,and the petrofacies were investigated by scanning electron microscope(SEM)and polarizing microscope.The results of MIP indicated that all samples’pores are mainly mesopore and have little macropore.The results from nitrogen adsorption indicated the most probable aperture of dolostone and dolomitic limestone were 2-4 nm,and argillaceous rocks did not have the aperture.The smaller dolomite in dolostone,the larger the BET porosity(2-200 nm);the porosity(2-200 nm)decreased with the size of calcite in dolomitic limestone with more smaller pores;the porosity(2-200 nm)increased with the content of acid-insoluble residua(AIR)in argillaceous dolomitic rock,and the smaller pores increased more than the bigger ones.There is no direct relationship between the porosity and the reaction degree of dolomite in dolomitic rocks.Both the porosity(2-200 nm)and the mean pore size were all increased by dedolomitization.

关 键 词：晶体尺寸 酸不溶物 孔结构 去白云化反应 白云质岩石 

分 类 号：TQ521[化学工程—煤化学工程]