Experimental investigation of fixed-bed pyrolysis and steam gasification of food waste blended with woody biomass

Abstract

The co-pyrolysis and co-gasification of woody biomass (oak) blended with food waste in a 2:1 ratio were investigated in a fixed bed tubular reactor. Gas compositions, gas yields, LHVs, H2/CO ratios and carbon conversions were evaluated between 700 and 900 °C reactor temperature and 7–22 g h−1 steam flow rate. The highest LHV of 11.03 MJ m−3 was measured during gasification at 900 °C reactor temperature with 7 g h−1 steam flow, and the LHV remained similar in both pyrolysis and gasification period. Typically, the H2/CO ratio ranged between 0.53 and 0.81 during pyrolysis, however, the ratio decreased by increasing the temperature. The gasification performed at 900 °C reactor temperature and 22 g h−1 steam flow resulted the most promising H2/CO ratio of 2.03 which has a great potential for further chemical processing. Additionally, the highest carbon conversion (99.7%) and gas yield (888.7 l kg−1) were measured at these conditions. Based on the results the co-pyrolysis and co-gasification of woody biomass and food waste is a viable method to reduce the accumulation of food waste and generate value added products.