(74g) Co-Gasification of Plastic, Coal Refuse, and Biomass for Hydrogen-Rich Syngas Production

Plastic waste has increasingly become one of the most pressing environmental concerns. To mitigate plastic emissions effectively, extraordinary efforts are needed for its recycling and management. Gasification is a promising recycling approach to produce hydrogen and syngas suitable for sustainable energy and fuel applications. This study delves into the thermochemical conversion of mixed feedstock blends containing plastic, coal refuse, and biomass into hydrogen-rich syngas via steam gasification. Coal refuse or biomass (such as pine dust) is incorporated as a co-feedstock with low-density polyethylene (LDPE) to improve the handling of plastic waste and explore their synergistic effects on carbon conversion and product distribution across a broad spectrum of reaction temperature and feedstock composition. The investigation underscores the significant influence of process parameters, particularly temperature variations and blend ratios, on hydrogen yield and syngas quality. These factors are pivotal in determining the co-gasification efficiency and environmental sustainability of the process. LDPE demonstrates higher reactivity compared to coal refuse and biomass, due to its higher volatile content. Increasing LDPE content in the feedstock blends correlates with enhanced hydrogen yield, reduced carbon monoxide levels, and elevated concentrations of C₁-C₃ hydrocarbons, particularly methane. Within the investigated temperature range (800-1000 °C), positive synergistic effects on carbon conversion efficiency and hydrogen-rich syngas production are more pronounced at higher temperatures, resulting in an overall enhancement of gasification performance. This study contributes to advancing waste-to-energy techniques and highlights the importance of co-gasification of plastic and biomass in reducing carbon emissions and promoting a circular economy.