Review of the Mechanisms and Prominent Factors in CO2-Accelerated Corrosion of Oilfield and Industrial Systems

Despite decades of investigation, a complete understanding of CO2 corrosion under complex environmental and operational conditions remains challenging. The stability and protective properties of corrosion-product scales across a wide range of service conditions are also poorly understood, limiting the effectiveness of corrosion management strategies. This review critically assesses CO2 corrosion behavior under diverse conditions, emphasizing how environmental and operational parameters influence corrosion rates and scale formation. The analysis draws on laboratory studies that identify key controlling factors, with particular focus on precipitation at the metal wall, film protectiveness, and scale degradation under different flow regimes. The literature is critically evaluated with respect to temperature, CO2 partial pressure (PCO2), salinity, pH, and hydrodynamic effects. The reviewed studies confirm that these parameters strongly govern CO2 corrosion rates and scale development. Protective FeCO3 films typically form under favorable supersaturation and precipitation conditions, commonly at 60–90 °C, but are prone to destabilization under high shear stress or in acidic environments. At low salinity, chloride ions enhance corrosion, whereas at high salinity, reduced CO2 solubility lowers corrosion rates and promotes weakly adherent scale formation. At low concentrations, H2S can substantially suppress CO2 corrosion by promoting FeS film formation that restricts anodic dissolution. However, its influence on corrosion behavior is not uniform and varies with material grade, solution pH, and prevailing environmental conditions. Overall, this review advances understanding of CO2 corrosion mechanisms and processes in industrial systems, and delineates environmental thresholds governing protective scale stability in CO2-containing environments.