^(99)Tc 在膨润土和北山花岗岩中的弥散行为  

Study on Dispersion Behavior of^(99)Tc in Bentonite and Beishan Granite

作　　者：李睿豪 王波[1] 陈曦[1] 徐毓炜 李遥 周舵[1] LI Ruihao;WANG Bo;CHEN Xi;XU Yuwei;LI Yao;ZHOU Duo(China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]中国原子能科学研究院,北京102413

出　　处：《世界核地质科学》2023年第S01期649-653,共5页World Nuclear Geoscience

基　　金：深部围岩条件下核素释出和迁移行为研究项目(编号:BD21000103);模拟处置条件下关键核素迁移相关物理化学特性研究(二期)(编号:BD18000103)联合资助。

摘　　要：^(99)Tc因其半衰期长达21万年且以TcO_(4)^(-)形式存在时随地下水迁移能力强,是高放地质处置中重点关注的核素之一。为估测^(99)Tc在北山高放候选处置废物地质场址中的迁移能力,研究了北山地下水中TcO_(4)^(-)在高庙子膨润土和北山花岗岩中的弥散行为。结果表明:地下水中TcO_(4)^(-)和3 H在高庙子膨润土和北山花岗岩中的弥散行为类似,表明膨润土和花岗岩对TcO_(4)^(-)迁移的阻滞能力很弱。地下水中TcO_(4)^(-)在高庙子膨润土和北山花岗岩中的弥散系数随水流速和温度的增大而增大,弥散度相对稳定。^(99)Tc is one of the key radionuclides considered in geological disposal of high-level radioactive waste,because it has a half-life up to 210000 years and can migrate rapidly with groundwater in the form of TcO_(4)^(-).In order to evaluate the mobility of^(99)Tc under Beishan repository condition,the dispersion behavior of TcO_(4)^(-)in Gaomiaozi bentonite and Beishan granite by using Beishan groundwater as background electrolyte was studied.The results showed that the dispersion behavior of pertechnetate and tritium water is similar in Gaomiaozi bentonite and Beishan granite,indicating that both bentonite and granite have weak retardation ability for TcO_(4)^(-).The dispersion coefficient of pertechnetate in Gaomiaozi bentonite and Beishan granite increased with increasing water velocity and temperature,and the dispersion is relatively stable.

关 键 词：^(99)Tc 高庙子膨润土 北山花岗岩 弥散 

分 类 号：TL942[核科学技术—辐射防护及环境保护] O69[理学—化学] O614.712