A new modeling approach for a CO2 capture process based on a blended amine solvent

The modeling procedure of an absorption-based carbon capture process using a blended amine solvent is presented. Semi-empirical correlation equations were developed for modeling the CO2 vapor-liquid equilibrium (VLE) and absorption rate in the ternary aqueous amine solvent used in this study. To reflect the non-ideality of the blended amine solvent in a CO2 loaded state, correction terms based on the fresh amine and free amine concentrations were added to the CO2 VLE and CO2 absorption rate models, respectively. The developed model was implemented in the commercial software PRO/II (R) by means of a user-added subroutine. Both the absorber and stripper were represented by rate-based models. The process behavior predictions by the proposed simulation model were compared with the pilot plant operation data. A quite satisfactory agreement between the model and data was obtained, which verifies the effectiveness of the proposed solvent modeling techniques.