Evaluation of buildup of activated corrosion products for highly compact marine reactor DRX without primary coolant water purification system

Japan Atomic Energy Research Institute has studied a highly compact reactor DRX for deep-sea research. The DRX has no purification system to achieve compact and light weight design by simplification of the system. The DRX is designed to operate for one month without purification of the primary coolant water. To quantitatively evaluate the validity of reactor operation without a purification system, a computer code CTAM-II has been developed to calculate accumulation of the activated corrosion products during and after reactor operation. The code is an improved and modified version of CTAM, which was developed for the shield modification project of the nuclear ship Mutsu. Validity of CTAM-II and parameters used in the code has been confirmed by comparison of the calculated data and experimental ones for measurement of the concentrations of radioactive materials in the primary coolant water. Estimation of buildup of the corrosion products for DRX using CTAM-II has been carried out and shielding calculations using source terms calculated from CTAM-II have been performed. A radiation safety assessment of the DRX without the purification system has been carried out by these shielding calculations. (author)