Corrosion Study on Wellbore Materials for the CO2 Injection Process

For reliability and safety issues of injection wells, corrosion resistance materials used needs to be determined. Herein, representative low-cost materials, including carbon steel X70/1.8977 low alloyed 1.7225, were embedded in mortar mimic the realistic casing-mortar interface. Two types cement investigated: (1) Dyckerhoff Variodur commercial Portland cement, representing a highly acidic resistant (2) Wollastonite, which can react with CO2 become stable under stream due carbonation process. Exposure tests performed 10 MPa at 333 K artificial aquifer fluid for up 20 weeks, revealing crevice uniform instead expected pitting corrosion. To clarify role simulated pore water was made by dispersing powder as solution expose steels. Surface analysis, accompanied element mapping on exposed specimens their cross-sections, carried out trace chloride intrusion process that followed.