The Oxy-CaL process: A novel CO2 capture system by integrating partial oxy-combustion with the Calcium-Looping process

Abstract

This paper proposes a novel CO2 capture technology from the integration of partial oxy-combustion and the Calcium-Looping capture process based on the multicycle carbonation/calcination of limestone derived CaO. The concentration of CO2 in the carbonator reactor is increased by means of partial oxy-combustion, which enhances the multicycle CaO conversion according to thermogravimetric analysis results carried out in our work, thus improving the CO2 capture efficiency. On the other hand, energy consumption for partial oxy-combustion is substantially reduced as compared to total oxy-combustion. All in all, process simulations indicate that the integration of both processes has potential advantages mainly regarding power plant flexibility whereas the overall energy penalty is not increased. Thus, the resulting energy consumption per kilogram of CO2 avoided is kept smaller than 4 MJ/kg CO2, which remains below the typical values reported for total oxy-combustion and amine based CO2 capture systems whereas CO2 capture efficiency is enhanced in comparison with the Calcium-Looping process.