[1J13-18] Corrosion, Electrochemistry, Radiolysis 3

[1J18] Challenge toward extensive corrosion prevention in PCV system under the Influence of α/β/γ radiation

(6)Investigation of corrosion inhibition effect of carbon steel by ultra-fine bubbles

*Yusuke Tsutsumi¹, Yusuke Muto², Hikari Watanabe², Isao Shitanda², Masayuki Itagaki², Hideki Katayama¹ (1. NIMS, 2. TUS)

Keywords:Corrosion, Radiolysis, Fukushima Daiichi Nuclear Power Station, Nuclear decommissioning, Ultra-fine bubble

In order to ensure the long-term reliability of PCV steel structures during the fuel debris removal process, the application of ultra-fine bubbles (UFB) was considered as a new corrosion prevention technology without any side effects. As a result of the corrosion behavior evaluation of carbon steel in the diluted artificial seawater with inert gas UFB, the corrosion inhibition effect was observed in the early stage of the immersion. This may be due to the efficient elimination of dissolved oxygen in the solution by the introduction process of UFB and the condition was maintained for a certain period. On the other hand, as the immersion period was prolonged, the difference between the conditions with/without UFB was no longer observed. Therefore, it is suggested that the injection of the treatment solution with inert gas UFB, either intermittently or continuously, would effectively prevent corrosion of steel structures.