Experimental study on the novel direct steam stripping process for postcombustion CO₂ capture

High energy consumption is a crucial issue for the regeneration of solvent for postcombustion CO₂ capture by chemical absorption. Primary modeling results show the potential to reduce the energy consumption through a novel solvent regeneration process by direct steam stripping. This work is an extension of our previous exploration and aims to validate the direct steam stripping process by experimental studies on a lab-scale stripping platform. We investigated the direct steam stripping and the conventional stripping mode in terms of energy consumption and steam condensation. The results showed, for the direct steam stripping mode, the optimum energy consumption at 1 atm was 2.98 MJ/kg CO₂, 23.2% lower than that of the conventional stripping mode. Higher solvent feeding temperature and carrier steam superheating temperature were beneficial to reduce steam condensation in the column. We found 96-99.5 °C feeding solvent temperature was suitable considering both the energy consumption and steam condensation. Besides, we proposed an improved direct steam stripping process using carrier gases such as hydrocarbon, which could further reduce the latent heat required.