Supercritical Water Oxidation (SCWO) has attracted considerable attention as an oxidation method for hazardous organic wastes like PCBs (Polychlorinated biphenyls), dioxine, TCE (Trichloroethylene). Although SCWO is technologically capable of the efficient destruction of hazardous wastes, the process must be carried out in a reactor that will withstand not only the conditions of high temperature and pressure, but also a very corrosive environment. Such problem of corrosion may ultimately be the deciding factor in the commercial application of this technology.
In this study, corrosion rates of Fe, Ni, Cr, Mo and SUS 316L were measured by LPR (Linear Polarization Resistance) method and weight loss method, in order to confirm the validation of electrochemical method in SCWO environment.
Corrosion test was performed under the condition of 400℃, 40 MPa in 0.1 M HCl solution. As corrosion rates of the metals obtained from LPR method were similar to those obtained from weight loss method, electrochemical method seems to effective method for corrosion. Also it was found that the main corrosion mechanism of SUS 316L was selective dissolution of Fe and Ni under the supercritical water condition.