Process modeling of chemical looping combustion (CLC) of municipal solid waste

Abstract

Chemical Looping Combustion (CLC) of MSW could serve as a potential treatment method for the disposal of MSW and the recovery of energy because it can inhibit dioxins and furans formation that is associated with the traditional treatment (incineration). This study evaluated the chemical looping combustion of MSW composition (Paper + Plastics) at different ratios using Chemcad® process simulation software. The process simulation was done for two different CLC processes namely Chemical Looping Oxygen Uncoupling (CLOU) and In-situ Gasification CLC (IG-CLC). Plastic samples used include polyvinyl chloride (PVC), high-density polyethylene (HDPE), low-density polyethylene (LDPE), polyethylene terephthalate (PET), polystyrene (PS) and polypropylene (PP). The results showed a promising CO2 yield (higher degree of CO2 capture) with the IG-CLC process having a higher CO2 yield (90–100%) than the CLOU process (30–80%) for the individual paper and plastic sample and the paper/plastic blends. For the combustion efficiency, the CLOU process was marginally higher than the IG-CLC process for all the plastics and the paper and while the IG-CLC process had higher combustion efficiency (30–75%) for the blends than the CLOU process (25–70%). Chlorine formation was used to measure the amount of dioxin formed; less chlorine means less dioxin formation. The results showed that the amount of chlorine formed decreases when paper and plastics were blended for all the different plastics except in PVC which increased for both CLOU and IG-CLC processes.