Corrosion behaviors of Ni-based and Fe-based alloys in supercritical water gasification with inorganic chloride salt

Supercritical water gasification (SCWG) technology is considered the most promising technology for treating oily wastewater. However, the impact of mixed inorganic salts on the reactor during the SCWG process of oily wastewater still lacks research. In this study, Fe-based alloys and Ni-based alloys were exposed to an environment of inorganic chloride salt in supercritical water. The analysis found that while Ni-based alloys have higher corrosion resistance than Fe-based alloys, in an environment of supercritical water containing inorganic chlorides, the surface corrosion of Fe-based alloys was significantly suppressed, while the surface corrosion of Nibased alloys was exacerbated.

Automated summary

Supercritical water gasification (SCWG) technology is considered promising for treating oily wastewater, but the impact of mixed inorganic salts on the reactor during the SCWG process is not well studied. This study exposed Fe-based alloys and Ni-based alloys to an environment of inorganic chloride salt in supercritical water. The analysis revealed that in an environment of supercritical water containing inorganic chlorides, Fe-based alloys showed suppressed surface corrosion, while Ni-based alloys exhibited exacerbated surface corrosion.