Predicting iron transport in a supercritical water cooled pressure tube reactor

The long-term viability of a supercritical water-cooled reactor (SCWR) will depend on the ability of designers to minimize corrosion and the transport of corrosion products and radionuclides. This paper presents thermochemical calculations of the effect of two different pH control agents, LiOH and NH3, on the solubility of magnetite under SCWR operating conditions. The HKF model was used to extrapolate thermochemical data for Fe(II) and Fe(III) aqueous species in the supercritical region, from which oxide and ferrite solubilities could be calculated. The results are being used to model iron corrosion product transport under SCWR conditions and to develop mitigating strategies. (author)