Integrated Modeling Approach for Electrochemical Regeneration of Alkaline CO₂ Capture Solvents

This work introduces a model for electrochemical CO₂ capture and solvent regeneration integrated with an Aspen Plus flowsheet. The model is built in Aspen Custom Modeler and designed to seamlessly integrate with ASPEN Plus software, allowing for comprehensive simulation of the CO₂ capture process using an electrochemical cell to regenerate the solvent. The model includes detailed descriptions of the mass and energy balances in the electrochemical stack compartments, mass transport over the ion exchange membrane, and potential losses through the stack. The validity of the model was assessed against laboratory measurements. The model was exemplified by modeling a CO₂ capture pilot plant for three different flue gases, from cement, magnesite, and gas-fired CHP production. The results of the integrated absorber-electrochemical system reveal key trade-offs among CO₂ capture efficiency, energy consumption, and throughput, highlighting the performance differences across the three case studies.