Influence of SO2 on the corrosion and stress corrosion cracking susceptibility of supercritical CO2 transportation pipelines

The impacts of SO2 on corrosion and stress corrosion cracking (SCC) of supercritical O-2 (s-CO2) pipeline steels are unclear because of limited field operation experience and somewhat controversial reported results. Comprehensive literature review and corresponding tests in the s-O-2 streams from advanced oxy-fuel plants were performed to fill significant knowledge gaps. The presence of SO2 leads to severe general corrosion but does not initiate SCC of the steels in H2O-saturated s-CO2. SO2 induced corrosion is likely dominated by electrochemical reactions. It is necessary to control H2O% < 2000 ppm and SO2% < 100 ppm to avoid potential catastrophic disaster.