压水堆核电站乏燃料元件γ扫描测量  

Gamma Scanning of Spent Fuel Element from PWR

作　　者：朱欣欣[1] 章安龙 王鑫[1] 王华才[1] 梁政强[1] ZHU Xinxin;ZHANG Anlong;WANG Xin;WANG Huacai;LIANG Zhengqiang(China Institute of Atomic Energy,P.O.Box 275-57,Beijing 102413,China;Daya Bay Nuclear Power Operation Management Co. , Ltd. , Shenzhen 518124,China)

机构地区：[1]中国原子能科学研究院反应堆工程技术研究部,北京102413 [2]大亚湾核电运营管理有限责任公司,广东深圳518124

出　　处：《原子能科学技术》2019年第5期893-898,共6页Atomic Energy Science and Technology

摘　　要：在压水堆核电站乏燃料元件检验中,完成了4根完整元件棒、4根破损元件棒的γ扫描测量,元件燃耗分布在9 600～45 000 MW·d/t(U)之间,获得了完整元件轴向相对燃耗分布、破损元件^(137)Cs分布及迁移流失情况。结果显示,破损元件均存在不同程度的Cs迁移流失,破口处存在^(137)Cs计数突变(降低)。破损元件^(134)Cs/^(137)Cs原子比分布与相邻完整元件基本一致,表明^(134)Cs、^(137)Cs流失比例近似相等,可用^(134)Cs/^(137)Cs原子比表征其相对燃耗分布;破口处可通过低挥发性核素^(154)Eu计数水平判断燃料芯块是否缺失。检验结果可为燃料元件破损原因分析及堆内行为分析提供重要依据。4 intact and 4 failed spent fuel elements from PWR with burnup range of 9 600-45 000 MW·d/t(U) were measured by gamma scanning,and the axial Cs distributions were obtained,which can indicate the burnup distribution of the intact elements and the Cs loss of the failed elements.The results show that there are different degrees of Cs migration and loss in the failed elements,and there is a Cs counting mutation (decrease) at the failure position.The distribution of 134Cs/137Cs atom ratio of one failed element is basically the same with the sibling intact element,indicating that the loss ratio of 134Cs and 137Cs is approximately equal,and the relative burnup distribution can be characterized by the atom ratio.The low volatility fission product 154Eu can be used to identify the fuel pellet damage.The results can provide an important basis for the failure cause analysis and the in-pile behavior analysis.

关 键 词：乏燃料元件 γ扫描 燃耗分布 Cs流失 燃料芯块缺失 

分 类 号：TL34[核科学技术—核技术及应用]