Acid Drop-Out in Carbon Capture and Transport Systems: Causes, Consequences, and Countermeasures

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Carbon capture and storage (CCS) is vital for net-zero goals.
• Transport and storage infrastructure are critical for CCS deployment.
• Pipeline integrity is threatened by impurities in CO2 streams.

Purpose of the Study:

• To review the impact of impurities on CO2 phase envelopes, acid formation, and pipeline corrosion.
• To assess mitigation and design strategies for CO2 transport.
• To identify knowledge gaps and future research needs for CCS.

Main Methods:

• Literature review focusing on impurity effects in CO2 pipelines.
• Analysis of phase behavior, acid formation, and corrosion mechanisms.
• Assessment of mitigation strategies including material selection and operational controls.

Main Results:

• Impurities like SOx, NOx, H2S, H2O, and O2 can cause acid precipitation and severe localized corrosion.
• These reactions alter CO2 phase behavior, leading to rapid wall-thickness loss.
• Current knowledge gaps exist regarding long-term performance under multi-impurity conditions and transients.

Conclusions:

• Effective impurity control and material selection are essential for safe CCS pipeline operation.
• Further research in experimental validation, modeling, and standards development is needed.
• Addressing these challenges will enable cost-effective and reliable CCS technology deployment.