Preheating temperature study of CO₂ thermal arc plasma assisted gasification for Municipal solid waste processing

The escalating concentration of CO₂ in the atmosphere necessitates the urgent development of technologies for its efficient conversion into valuable products such as fuel, contributing to carbon neutrality and sustainable energy solutions. This study examines the effect of preheating temperature on thermal plasma-assisted gasification for syngas production from processing of municipal solid waste (MSW). A 5 kg/h capacity plasma gasification chamber was designed and developed, employing a graphite electrode-based non-transferred plasma system with CO₂ as the carrier gas. The use of graphite electrodes offers advantages including reduced power consumption by eliminating water cooling requirements and providing additional carbon particles that augment CO content in the syngas, thereby enhancing its calorific value. The plasma chamber temperature was maintained above 850°C to suppress the formation of toxic gases during waste feeding and processing. Due to the consumable nature of graphite electrodes, their consumption rate was analyzed to assess the techno-economic viability of the system. Product gases were sampled from multiple ports within the chamber to investigate variations in gas composition, facilitating the optimization of syngas quality. Special attention was given to the recombination reactions inherent in CO₂ plasma processes, which influence product composition. This work advances the understanding and operational parameters of plasma gasification for efficient waste-to-energy conversion, promoting an eco-friendly route for CO₂ utilization and renewable fuel production.