不同温度对钚在北山地下水中溶解行为的影响  

Effect of Different Temperatures on the Dissolution Behavior of Plutonium in Groundwater of Beishan

作　　者：龙浩骑[1] 周舵[1] 王波[1] 姜涛 包良进[1] LONG Haoqi;ZHOU Duo;WANG Bo;JIANG Tao;BAO Liangjin(China Institute of Atomic Energy,P.O.Box 275(93),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》2022年第2期262-268,共7页World Nuclear Geoscience

摘　　要：核素溶解度是高放废物固化体中浸出的核素在地下水中迁移的浓度上限,是高放废物地质处置安全和环境评价中的关键参数。钚是高放废物深地质处置重点关注元素,研究了模拟处置条件下不同温度对钚在北山地下水中溶解行为的影响。实验采用过饱和法,使用低氧手套箱模拟地下无氧环境,利用超过滤实现固-液分离,应用低本底液闪谱仪测量液相中钚的放射性活度。实验结果表明,在溶解-沉淀平衡后,钚的主要存在价态为4+价,有少量的5+价。体系温度为(30±1)、(45±1)和(60±1)℃时,钚在北山地下水的溶解度分别为(3.06±0.97)×10^(-8)、(3.16±1.27)×10^(-10)和(1.34±0.67)×10^(-10) mol·L^(-1)。体系温度升高,钚在北山地下水中的溶解度下降,有利于阻滞钚的迁移。Radionuclide solubility is the upper limit of the concentration of radionuclides leached from the high-level radioactive waste in groundwater.It is a key parameter in the safety assessment of geological disposal of high-level radioactive waste.Plutonium is a key element for deep geological disposal of high-level radioactive waste.The effect of different temperatures on the dissolution behavior of plutonium in groundwater of Beishan was studied in this paper.The underground anaerobic condition was simulated in glove-box.The solid-liquid separation was achieved by ultrafiltration.The plutonium radioactivity was measured by low background liquid scintillation spectrometer.The results show that the dominant oxidation state of plutonium in groundwater is tetravalent and a small amount is pentavalent.System temperature is(30±1),(45±1)and(60±1)℃,the plutonium solubility in Beishan groundwater are(3.06±0.97)×10^(-8),(3.16±1.27)×10^(-10) and(1.34±0.67)×10^(-10) mol·L^(-1).With the increase of temperature,the solubility of plutonium in groundwater of Beishan will decrease,which is beneficial to the retardation of plutonium migration.

关 键 词：北山地下水 钚 溶解度 温度 

分 类 号：TL942[核科学技术—辐射防护及环境保护]