Evaluation of the chemical looping gasification characteristics of kitchen waste using CuFe 2 O 4 and NiFe 2 O 4 as oxygen carriers

Chemical looping gasification (CLG) technology is promising for renewable energy, efficiently transforming biomass into high-quality syngas with minimal tar and pollutants. In this study, we examined the CLG characteristics of soy protein (SP), a model compound present in kitchen waste (KW), using two different oxygen carriers (OCs): Cu-Fe and Ni-Fe. The study revealed that enhancing the carbon conversion ratio ( η c ) could be effectively achieved by increasing the oxygen equivalent coefficient ( α ) and the steam content. Consequently, the optimal gasification performance was attained when the Cu-Fe and Ni-Fe OCs were operated at the α values of 0.3 and 0.4, and steam contents of 30 % and 40 %, respectively. After ten cycles of chemical looping, both OCs retained their robust oxidation activity, ensuring that the η c remained consistent throughout the ten cycles. Under optimized experimental conditions, the CLG characteristics of KW were successfully determined. Notably, the η c of KW was substantially enhanced, doubling in comparison to previous levels. The Cu-Fe OC emerged as a more suitable candidate for the CLG of KW due to its lower cost and non-toxic nature. This study provides important theoretical support and practical insights for the harmless treatment and resource utilization of KW.