Simulation of the Post-combustion CO2 Capture with Aspen HysysTM Software: Study of Different Configurations of an Absorption-regeneration Process for the Application to Cement Flue Gases

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Abstract The purpose of this study was to simulate, using Aspen Hysys TM with Amine Package and Kent-Eisenberg model for thermodynamic calculation, the post-combustion CO 2 capture and to compare different configurations of the absorption- regeneration process. In this paper, considering MEA 30% as solvent, we focused on three alternative configurations: the “Stripper Split Feed” (SSF), the “Lean Vapor Compressor” (LVC) and their combination. One of the specific aspects of this work is the fact that we considered cement flue gases, where the CO 2 content (from 20 to 30 wt.%) is higher than the one from conventional power plants (from 5 to 15 wt.%, generally considered in other studies) and which leads to different results in terms of energy savings. In a first step, the result of our simulation model was successfully validated with the use of literature results considering the St Marys cement plant in Canada as case study (CO 2 content of 24 mol.% in the gas to treat) and the classical configuration of the process. The boiler duty of the MEA 30% solvent calculated by our simulation model was equal to 3.71 GJ/tCO 2 (CO 2 capture rate of 85% with a purity of 98%) which is coherent with the literature value (3.68 GJ/tCO 2 ) considering identical operating parameters. The second step of the study was the simulation of this CO 2 capture process considering the same conditions (cement flue gases and MEA 30%) but investigating the three alternative configurations. Globally, this step highlighted that also for the CO 2 capture applied to cement flue gases significant regeneration energy savings (around 24%) are achievable thanks to the use of alternative configurations of the absorption-regeneration process. As perspectives, these simulation results will be compared to the ones obtained using the new Acid Gas Package developed by Aspen Hysys. Other innovative configurations (such as Stripper Overhead Compression “SOC”) will be simulated and the focus will be also put on other solvents (simples or activated solutions).