PSI - Issue 80

G. Mubarak et al. / Procedia Structural Integrity 80 (2026) 157–168 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

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Figure 6: pH and flow regime of the first and last 30 days of the well’s production.

Figure 7: Non-linear relationship of CO 2 solubility and temperature [28]

4. Failure mechanism analysis The failure mechanism analysis of the CO₂ corrosion -induced damage in the tubing system revealed that localized corrosion and pitting were primarily driven by chloride-accelerated breakdown of protective scales, particularly iron carbonate (FeCO₃). XRD and chemical spot testing confirmed the formation of FeCO₃ on all surfaces, most notably on the ID, where its corrosion-inhibiting effectiveness was validated through copper sulfate testing. However, corrosion was evident in regions where the FeCO₃ scale was compromised, especially under the influence of chlorides from produced water, which are widely recognized to accelerate corrosion reactions [30] – [34]. The solubility and protective efficacy of FeCO₃ were strongly dependent on system temperature and chloride concentration [35]; higher