[3F05-09] Decommissioning Technology

[3F07] Evaluation of the effect of random storage in clearance measurement containers on the radioactivity conversion factor (3)

Quantification of maldistribution of density and specific surface area in units of measurement

*Masato Watanabe¹, Ryouji Mizuno², Toshio Kuzuya³ (1. Chubu Electric Power, 2. Chuden CTI, 3. Techno Chubu )

Keywords:clearance, BWR, radiation, Ge semiconductor detector, Units of Measurement

In order to apply the clearance system to metal scraps generated in the decommissioning of nuclear facilities, they are stored in containers and their radioactivity is measured. In order to perform this measurement more accurately, we are developing a program that can calculate the effects of uneven distribution of metal scrap density and uneven distribution of radioactivity on the measurement of radioactivity. This program can quantify uneven distribution of density and specific surface area when scrap metal is randomly placed in a container. The quantification results showed that the uneven distribution of density and specific surface area did not become large compared to the uniform distribution when the metal scraps were randomly placed in the measurement container. However, consideration was given to the storage of these so as to reduce uneven distribution based on human subjectivity.