Performance of a kaolin-doped, magnetic Cu-based oxygen carrier in biomass combustion

Abstract

Chemical looping combustion with oxygen uncoupling (CLOU) enables solid fuel combustion with CO2 capture at low cost due to the capacity of the oxygen carrier to release molecular oxygen. The present study is focused on testing the performance of a magnetic Cu-based oxygen carrier with reinforced mechanical properties owing to the addition of kaolin via the combustion of three types of biomass in a 1.5 kWth continuous CLOU unit. The effect of the main operating variables on process performance parameters was studied. Complete combustion of the different biomass types was achieved. Higher CO2 capture efficiencies were observed at 800–950 °C compared to the previous work done with this oxygen carrier without kaolin doping. The highest value of 97.5% CO2 capture efficiency was obtained at 950 °C during the combustion of pine sawdust. Moreover, the oxygen carrier retained its magnetic properties without any agglomeration problems after 80 h of hot circulation operation.