INTERACTIONS BETWEEN CARBON STEEL AND UO_2 CORROSION FRONTS INSIDE A FAILED NUCLEAR WASTE CONTAINER

摘要

The corrosion of carbon steel in the chloride-dominated groundwaters anticipated inside a failed spent fuel waste container has been studied in the presence of small concentrations of added hydrogen peroxide. Solutions with peroxide concentrations in the micro-molar range were found to accelerate steel corrosion slightly leading to the formation of Fe~Ⅲ-containing corrosion product deposits but not to passivation of the steel. Calculations using a model for fuel and steel corrosion inside a failed waste container show that peroxide concentrations at the steel surface should be many orders of magnitude less than these micro-molar levels. It can be concluded that the redox scavengers, Fe~(2+)and H_2, produced by the active corrosion of the steel, will be available to suppress the radiolytic corrosion of the fuel and to avoid the associated radionuclide release processes.