The corrosive effects of iron monosulfide deposited on carbon steel surfaces were investigated in autoclave experiments. The H2S and CO2 partial pressures were 1 to 20 bar. Temperatures were 10-120 °C. The test solutions consisted of high-salinity brine and low-salinity condensed water. Typical duration was 14 days. Weight loss and localized corrosion data were obtained.
An improved sour corrosion model was developed based on: • A bare steel sour electrochemical corrosion model, derived from published literature • Mechanisms that affect scale performance and trigger localised corrosion • A specific elemental sulphur degradation mechanism • Corrosion mitigation strategy