Evaluation of curve for tritium release rate into primary coolant for research and testing reactors

Kenzhina, I. E.*; Ishitsuka, Etsuo   ; Okumura, Keisuke ; Takemoto, Noriyuki ; Mukanova, A.*; Chikhray, Y.*

Increase of tritium concentration in the primary coolant for research and testing reactors during reactor operation had been reported. To clarify the tritium sources, a curve of tritium release rate into the primary coolant for the JMTR and JRR-3M are evaluated. As a result, the tritium release rate is related with produced Li by (n,) reaction from Be, and evaluation results of tritium release curve are shown as the dominant source of tritium release into the primary coolant for the JMTR and JRR-3M are beryllium components. Scattering of the tritium release rate with irradiation time were observed, and this phenomena in the JMTR occurred in earlier time than that of the JRR-3M.