Municipal solid waste air gasification using waste marble powder as a catalyst for syngas production

Abstract

Waste marble powder (WMP), the main pollutant in the marble processing industry, is predominantly composed of calcite. Its rich calcium-based nature, derived from calcite, positions it as an excellent source for a CO2 sorbent, making it highly conducive to serving as a catalyst. Also, extraction of energy from MSW is the best option to discard solid waste along with protection from global warming and landfill burden. The present study aims to investigate MSW potential as feedstock with WMP as a CO2 sorbent for syngas in air gasification lab-scale fixed-bed gasifier. The system was initially tested on different equivalence ratios (ER) (0.25, 0.30, and 0.35) to search for an optimum value. The optimum value of ER for this study was found to be 0.30 with the composition of CO, CO2, CH4, and H2 were 10, 8.97, 1.67, and 6.65 vol%, respectively. The main study investigated the influence of different weight ratios of WMP to MSW (0.05, 0.1, 0.15, and 0.2) on the gas composition, carbon conversion efficiency, and carbon gasification efficiency, and higher heating values. The results indicated that the presence of WMP promotes H2 and CO significantly, whereas CO2 content was reduced to 0.20 vol% when compared to runs without utilizing WMP (9 vol%). For this study, loading the WMP catalyst exhibits a remarkable effect on syngas composition with the optimum ratio of 0.1–0.15.