Process for decontaminating a nuclear reactor coolant system

摘要

High velocity reactor coolant water in a boiling water reactor or a pressurized water reactor transports radioactive ions and particles from a nuclear reactor vessel to the balance of the reactor coolant system where they deposit on chromium (III) oxide-containing surfaces. These radioactive deposits are removed in a dilute chemical decontamination process wherein permanganate ion-containing reactor coolant water is circulated throughout a reactor coolant system to oxidize chromium (III) oxide surfaces of the system to chromium (IV) oxide. Formic acid is added to the permanganate ion-containing reactor coolant water and then the formic acid-containing water is circulated throughout the reactor coolant system to reduce unreacted permanganate ions in the reactor coolant water to manganous ions.