2021 Volume 70 Issue 12 Pages 392-395
One of the corrosion mitigation methods, hydrazine （N2H4） addition to spent nuclear fuel pool （SFP） cooling water, was adopted in Fukushima Dai-ich nuclear power station （1F）. It is well-known that deoxygenation of high temperature water by N2H4 is effective but the effect is smaller at the room temperature. However, gamma-ray irradiation would accelerate the deoxygenation reaction of N2H4. To clarify the acceleration effect, gamma-ray irradiation tests of N2H4 containing water were conducted in various conditions. Dissolved oxygen （DO） concentration rapidly decreased by gamma-ray irradiation, in both cases N2H4 added pure water and artificial sea water. The process was confirmed by the gamma-ray radiolysis model. These data pointed out a scientific meaning to the corrosion mitigation methods of 1F site.
