Corrosion in CO2 Capture and Transportation

In post-combustion CO2 capture, amine-based absorbents are the most-widely used CO2 capture agent. Corrosion is considered to be one of the most severe operational problems in amine-based CO2 absorption processes and experience shows that amine degradation products often aggravate corrosion. In general, amines are not intrinsically corrosive, but amines may become corrosive when they absorb CO2. Furthermore, since the treatment units operate in semi-closed circuit, the solvent may become enriched with possibly corrosive degradation products. CO2 transportation is an important stage in whole-chain CCUS projects. Impurity is an important factor in CO2-induced transport pipeline corrosion. H2O, NOx, O2, H2, CH4, H2S, etc. are typical impurities that may accelerate CO2 corrosion in pipeline CO2 transportation. The properties of CO2 containing impurities determine the parameters of phase equilibrium, density, compressibility, viscosity, etc., which influence a series of system parameters like the pressure curve/loss conditions, heat transfer, flow volume, etc. in the pipeline transportation process. The changes of those system parameters in turn affect the potential for CO2-induced pipeline corrosion.