Verification Test on Zinc Injection Adjusted to Japanese BWR Water Chemistry

摘要

The verification test on zinc injection, sponsored by MITI as a national project, has started from 1997. The laboratory tests using the high temperature water loops under BWR reactor water condition are in progress. This paper describes the results obtained so far as an interim report. The gamma ray irradiation accelerates the corrosion under the NWC condition, but the gamma ray irradiation does not significantly accelerate the corrosion under the HWC condition. The effect of gamma ray irradiation on the incorporation of Co into the oxide film is small. The presence of 2 ppb Zn in high temperature water sufficiently suppresses the incorporation of Co into the inner oxide layer of stainless steel. However, more Zn needs to suppress Co incorporation into the outer oxide layer. Zn deposition on stainless steel does not increase in proportion to Zn concentration in high temperature water.