CO2 capturing from power plant flue gases: Energetic comparison of amine absorption with MgO based, heat integrated, pressure–temperature-swing adsorption

Abstract

In this work, a novel, heat-integrated, pressure–temperature-swing-adsorption (PTSA) process is proposed for the capture of CO2 from the flue gas of fossil-fueled power plants. The proposed PTSA process utilizes MgO to capture CO2, in cyclic adsorption/desorption steps involving temperature and pressure swings. The adsorption/desorption temperature and pressure operating conditions are found by globally solving the associated Gibbs free energy minimization problem. The proposed process is heat-integrated, and involves a heat-pump, a refrigeration loop, a flash-separator train with inter-stage compression and cooling, and a heat exchange network. Our energetic analysis suggests that a 12% increase in power output can be attained for 90% CO2 capture, over an amine process featuring the same CO2 capture level.