A comparative study of chemical looping combustion (CLC) with paper, plastic, and coal as fuel was carried out. Experiments were performed in a laboratory fluidized‐bed reactor by alternating between reduction and oxidation cycles. The results obtained indicated that a higher temperature leads to an increase in the CO2 yield and carbon conversion for all fuels. Paper had the highest fractional conversion of CO to CO2 followed by polyvinyl chloride (PVC) and coal. This was due to the higher fraction of volatiles in paper compared to PVC and coal. Scanning electron microscopy (SEM) analysis of the oxygen carrier particle after each of the solid fuel experiment was carried out. For the used ilmenite, there was a slight difference in the morphology for the three different fuels.

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Chemical looping combustion (CLC) is a novel carbon capture and storage technology that can be used in the proper disposal of municipal solid waste when used as a solid fuel. In this study, the results of the CLC of paper, plastics, and paper/plastic blends were compared with CLC of South African coal using Chemcad software. The simulation was done for two different CLC processes, namely, chemical looping oxygen uncoupling (CLOU) and in situ gasification CLC (IG-CLC). The results demonstrated that coal at 66% had a lower CO 2 yield than paper (86%) but a higher yield than all the plastic samples in CLOU (3356%) and an equal CO 2 yield in paper and all plastic samples in IG-CLC. Furthermore, coal had a lower CO 2 gas yield than all the optimum blends (72–85%) for CLOU and an equal yield with the entire paper/plastic blend in IG-CLC. On combustion efficiency, coal has a lower combustion efficiency at 80% than paper and polyvinyl chloride (PVC) at 90 and 96%, respectively, but a higher efficiency than other plastic samples that are between 30 and 70% in CLOU while in IG-CLC, it had a lower efficiency than paper, PVC, and polyethylene terephthalate and higher efficiency than high-density polyethylene, low-density polyethylene, polypropylene, and polystyrene. For paper/plastic blends, coal has higher combustion efficiency than all the paper/plastic blends in both CLOU and IG-CLC processes except for the paper/PVC where the combustion efficiency was higher than coal.

Chemical Looping Combustion (CLC) has been found to be a better alternative in converting Municipal Solid Waste (MSW) to energy and has the potential to reduce the generation of dioxins due to the inhibition of the de-novo synthesis of dioxins. This study comprehensively reviews the experimental studies of CLC of MSW, the oxygen carriers, reactor types, performance evaluation, and ash interaction studies. Modeling and simulation studies of CLC of MSW were also critically presented. Plastic waste is MSW’s most studied non-biomass component in MSW under CLC conditions. This is because CLC has been shown to reduce the emission of dioxins and furans, which are normally emitted during the conventional combustion of plastics. From the several oxygen carriers tested with MSW’s CLC, alkaline earth metals (AEM) modified iron ore was the most effective for reducing dioxin emissions, improving combustion efficiency and carbon conversion. Also, oxygen carriers with supports were more reactive than single carriers and CaSO4/Fe2O3 and CaSO4 in silica sol had the highest oxygen transport ability. Though XRD analysis and thermodynamic calculations of the reacted oxygen carriers yielded diverse results due to software computation constraints, modified iron ore produced less HCl and heavy metal chlorides compared to iron ore and ilmenite. However, alkali silicates, a significant cause of fouling, were observed instead. The best reactor configuration for the CLC of MSW is the fluidized bed reactor, because it is easy to obtain high and homogeneous solid–gas mass transfer. Future research should focus on the development of improved oxygen carriers that can sustain reactivity after several cycles, as well as the system’s techno-economic feasibility.

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