CO2 Capture by Calcium Looping at Relevant Conditions for Cement Plants: Experimental Testing in a 30 kWth Pilot Plant

Abstract

Calcium looping technology has a high potential for capturing CO2 in cement plants as the CaO-rich purge from the calciner can be used to replace a sizable fraction of the CaCO3 used as feedstock. Integrating the CaL process into the cement plant requires the carbonator reactor to operate under new conditions (i.e., a higher carbonator CO2 load, a more active sorbent, smaller particle sizes). This work analyzes the impact of some of the new CaL operating conditions on the performance of the carbonator in a retrofitted 30 kWth testing facility as there is little experimental information available nowadays. A wide range of sorbent activities has been tested, including those corresponding to very large makeup flows of limestone that would be characteristic of CaL applications in cement plants. The results have been interpreted using a basic reactor carbonator model that required little modification of previous versions developed for power plants.