钙基膨润土对^(239)Pu核素迁移的阻滞性能研究  

Retardation Capability of Ca-bentonite on Migration of ^(239)Pu

作　　者：岳萍[1,2] 庹先国[2,3] 冷阳春[1,2] 刘明哲[1,2] 宿吉龙[1,2] 

机构地区：[1]成都理工大学地质灾害防治与地质环境保护国家重点实验室 [2]成都理工大学核技术与自动化工程学院,四川成都610059 [3]西南科技大学核废物与环境安全国防重点学科实验室,四川绵阳621000

出　　处：《环境科学与技术》2014年第8期17-20,53,共5页Environmental Science & Technology

基　　金：国家杰出青年科学基金项目资助(41025015);四川省青年科技创新研究团队(2011JTD0013)

摘　　要：文章采用动态淋滤实验,研究了不同流速和水相pH下,钙基膨润土对239Pu核素迁移的阻滞性能。实验结果表明:钙基膨润土对239Pu核素迁移的阻滞性能很好,100 d内淋出液中的放射性总量很少,239Pu的淋出率最高仅为6.166‰,最小能达到0.209 7‰。流量和水相pH均会影响膨润土的阻滞性能,但是流量的影响更加明显,核素的淋出率随着流速的增大而增大。水相pH一方面改变了土壤性质,使土壤的渗水性能产生变化,另一方面影响了膨润土对239Pu的吸附能力。2种影响同时作用,最终导致水相pH对淋出率的影响不成线性关系。在酸性水相条件下,膨润土的渗水性大大降低,阻滞性能达到最优。Retardation capability of Ca-bentonite on migration of ^239Pu under different flow rates and aqueous phase pH was studied by using dynamic leaching experiments. Result showed that Ca-bentonite has a good block retardation capability on ^239Pu. Within 100 days,the total radioactivities of leachates are very low. The highest leaching rate of ^239Pu is only 6.166%, and the lowest is 0.209 7%. The flow rate and aqueous phase pH both affect the retardation capability of Ca-bentonite, but the flow rate has a stronger affection. Leaching rate of ^239Pu increases as the flow rate growing. The aqueous phase pH changes the properties of soil, which causes the change of permeability of bentonite, while it affects the adsorption abilities of bentonite of ^239Pu . With these two effects, the leaching rate of ^239Pu doesn＇t have a linear relation with the aqueous phase pH. Under acidic aqueous condition, the permeability of bentonite reduces greatly, and shows a strong retardation capability.

关 键 词：^239Pu 钙基膨润土 阻滞性能 

分 类 号：X131.3[环境科学与工程—环境科学]