Supercritical water gasification of food waste: Effect of parameters on hydrogen production

Food waste is a type of municipal solid waste with abundant organic matter. Hydrogen contains high energy and can be produced by supercritical water gasification (SCWG) of organic waste. In this study, food waste was gasified at various reaction times (20-60 min) and temperatures (400 degrees C-450 degrees C) and with different food additives (NaOH, NaHCO3, and NaCl) to investigate the effects of these factors on syngas yield and composition. The results showed that the increase in gasification temperature and time improved gasification efficiency. Also, the addition of food additives with Na+ promoted the SCWG of food waste. The highest H-2 yield obtained through non-catalytic experiments was 2.0 mol/kg, and the total gas yield was 7.89 mol/kg. NaOH demonstrated the best catalytic performance in SCWG of food waste, and the highest hydrogen production was 12.73 mol/kg. The results propose that supercritical water gasification could be a proficient technology for food waste to generate hydrogen-rich gas products. (C) 2020 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.