Ca^(2+)盐溶液在高庙子膨润土中的扩散研究  

Study on spontaneous diffusion of CaCl_(2) solution in GMZ Na-bentonite

作　　者：杨婷[1,2] 杨成艳 郑举功 查文化[1] 梁海安 冯岩岩[1] YANG Ting;YANG Chengyan;ZHENG Jugong;ZHA Wenhua;LIANG Haian;FENG Yanyan(East China University of Technology,Nanchang 330013;State Key Laboratory of Nuclear Resources and Environment,Nanchang 330013)

机构地区：[1]东华理工大学,南昌330013 [2]核资源与环境国家重点实验室,南昌330013

出　　处：《辐射防护》2022年第2期146-154,共9页Radiation Protection

基　　金：国家自然科学基金(51869002);放射性地质与勘探技术国防重点学科实验室项目(RGET1811)。

摘　　要：高放废物地质处置库近场地下水可能会对处置库内的屏障体系产生影响,降低处置库的安全稳定。为研究地下水中盐离子在处置库内缓冲回填体系的扩散规律,本文开展了静态无外荷载条件下内蒙古高庙子(GMZ)膨润土在Ca^(2+)盐溶液中自发渗吸的吸附扩散室内试验。从土的微观结构和经典扩散理论对Ca^(2+)在不同干密度和初始饱和度的膨润土试样中的自发扩散规律进行了分析。研究结果表明,在膨润土初始饱和度相同的情况下,试样阻滞系数随其干密度增加而增大,此时Ca^(2+)的扩散能力减弱;当膨润土干密度相同时,随着初始饱和度的增加基质吸力作用减弱,阻滞系数减小,Ca^(2+)的扩散能力减弱。The groundwater at the near site of the geological disposal repository of high-level radioactive waste may affect the barrier system in the disposal repository and may reduce the safety and stability of the disposal repository.In order to study the diffusion law of salt ions in the groundwater into the buffer backfill system in the disposal repository,the spontaneous imbibition,adsorption and diffusion of Gaomiaozi(GMZ)bentonite from Inner Mongolia in Ca^(2+) solution was carried out in laboratory under static non-external loading condition.The spontaneous diffusion of Ca^(2+) in bentonite samples with different dry densities and initial saturation was analyzed based on soil microstructure and classical diffusion theory.The results showed that under the condition of the same initial saturation of bentonite,the retardation coefficient increases with the increase of dry density,while the diffusion capacity of Ca^(2+) decreases.When the dry density of bentonite was the same,the retardation coefficient and diffusion capacity of Ca^(2+) decrease with the increase of initial saturation.

关 键 词：高放废物处置 钠基膨润土 自发扩散 扩散系数 FICK第二定律 

分 类 号：TL942.1[核科学技术—辐射防护及环境保护]