极低放射性废物填埋场中同位素迁移与屏障研究  

Isotope migration and barrier in a VLLW site

作　　者：康厚军[1] 张东[1] 杨勇[1] 李宽良[2] 张佩聪[2] 石正坤[1] 

机构地区：[1]中国工程物理研究院核物理与化学研究所,绵阳621900 [2]成都理工大学,成都610059

出　　处：《核技术》2010年第4期289-293,共5页Nuclear Techniques

摘　　要：在查明场址地球化学特征的基础上,研究了238U、90Sr在场址包气带土壤中的吸附与迁移特征。设计了一系列非均匀介质实验模型,研究了在瞬时源和连续源条件下238U、90Sr在非均匀介质中的迁移特征。同位素迁移屏障研究在研究场址围岩对核素的吸附特征的基础上,筛选出合适的矿物添加剂以提高场址岩土对90Sr迁移的屏障能力。结果表明,238U和90Sr在场址土壤中迁移速度分别为0.365和0.385mm/a。非均匀介质对同位素迁移影响首先是减弱了主流体的污染强度,同时延长了污染作用时间;添加剂人造沸石可作为90Sr迁移屏障材料。In this work, adsorption and migration of ^238U and ^90Sr in tmsaturated soil at a VLLW （very low level waste） site was investigated, in an attempt to find geochemical features of the site. Migration of the isotopes in heterosphere was studied under instantaneous and sequential conditions of the sources. The migration barrier experiment was carried out in two steps on wall rock absorption of the isotopes and addictives to improve the barrier of the wall rock to ^90St. The results show that the migration speed of ^238U and ^90Sr in the soil is 0.365 and 0.385 mm/a, respectively. The heterosphere effects on the isotope migration not only alleviated the mainstream contamination, but also prolonged the time of contaminated affection. And false zeolite should be used as barrier additive material for ^90Sr migration.

关 键 词：极低放废物 填埋场 选址 U SR 迁移 

分 类 号：O647.3[理学—物理化学]