A review of the protection strategies against internal corrosion for the safe transport of supercritical CO2 via steel pipelines for CCS purposes

The transport of carbon dioxide (CO2) from its source to a storage site is a key component of the carbon capture and storage (CCS) process. CO2 transportation by steel pipelines presents a durability risk in the form of internal corrosion damage from supercritical or liquid CO2 transmission. This risk is due to the formation of carbonic acid as a result of any H2O presence, and in situ speciation of acids such as sulphurous (H2SO3), sulfuric (H2SO4), hydrochloric (HCl), and nitric acids (HNO3) due to the presence of impurities. This review paper aims to present three key potential protection strategies to mitigate or reduce the threat of corrosion damage for reliable and potentially cost-effective transport of CO2. This includes review of (a) relevant corrosion inhibitors, (b) corrosion resistant alloys (CRAs) for CO2 transport pipeline, and (c) the role and physical properties of a protective iron carbonate layer (FeCO3).