Corrosion Mechanisms in Carbon Steel in Oil and Gas Systems

Carbon steel pipelines and equipment in oil and gas operations are exposed to complex corrosive environments where acidic gases, water and multiphase fluids interact to degrade material integrity. In CO₂‐rich “sweet” environments, dissolution of iron and precipitation of iron carbonate (FeCO₃, siderite) can form protective scales, but these layers may be porous or brittle under fluctuating temperature, pressure and flow conditions, leading to local breakdown and pitting. In sour service, H₂S promotes formation of iron sulfide films that are often less protective and can give rise to sulfide stress corrosion cracking. Oxygen ingress further complicates corrosion by generating iron oxides and mixed‐oxide layers. Hydrodynamic factors, emulsified water droplets and wettability phenomena in oil–water mixtures create micro‐environments with high ion concentration and variable diffusion paths, driving localised attack beneath oil films or in crevices. The evolution of dual‐layer scales, interplay between anodic dissolution and cathodic gas reduction, and synergistic effects of temperature, salt concentration and multiphase flow determine corrosion rates and failure modes. Understanding these mechanisms is critical to global efforts in extending asset life, optimising inhibitor regimes and designing alloys or coatings for safe, cost‐effective hydrocarbon production.

Research from Nature Portfolio

No recent Nature Portfolio content available.

Corrosion Mechanisms in Carbon Steel in Oil and Gas Systems publication trend

The graph below shows the total number of articles in corrosion mechanisms in carbon steel in oil and gas systems across all publications each year (not limited to Nature Index journals).

Technical terms

FeCO₃ (Siderite): Iron carbonate corrosion scale that can impart partial protection in CO₂‐rich environments.

Pitting corrosion: Localised attack producing cavities when protective films break down.

Sweet corrosion: Corrosion in CO₂‐dominated (H₂S‐free) conditions characterised by siderite formation.

Sour corrosion: Corrosion in H₂S‐containing environments leading to iron sulfide films and potential cracking.

Mixed potential theory: Electrochemical framework balancing anodic metal dissolution and cathodic gas or ion reduction.

Hydrodynamic conditions: Flow regimes affecting mass transport, scale adhesion and film removal.

References

1. A synergistic experimental and computational study on CO2 corrosion of X65 carbon steel under dispersed droplets within oil/water mixtures. Corrosion Communications (2023).
2. Electrochemical and Sulfide Stress Corrosion Cracking Behaviors of Tubing Steels in a H2S/CO2 Annular Environment. Journal of Materials Engineering and Performance (2014).
3. Temporal evolution of sweet oilfield corrosion scale: Phases, morphologies, habits, and protection. Corrosion Science (2018).
4. Corrosion Control in CO2 Enhanced Oil Recovery From a Perspective of Multiphase Fluids. Frontiers in Materials (2019).
5. CO2 Corrosion of Low Carbon Steel Under the Joint Effects of Time-Temperature-Salt Concentration. Frontiers in Materials (2019).