Thermochemical liquefaction of biomass wastes and unused biomass

Abstract

Heavy oil was produced from biomass wastes and unused biomass by thermochemical liquefaction using alkali catalyst in hot-compressed water of around 300°C and 100 atm respectively, without any reducing gas. Oil yields varied in the range of 19-65 wt%. Effects of operating parameter such as catalyst loading, reaction temperature and holding time on oil yield and its properties were examined experimentally for each biomass feedstocks. Based on experimental results, the relationship between the oil yield and its properties was discussed. The oil obtained in high yield had high calorific value and low viscosity, while the oil obtained in low yield had low calorific value and high viscosity. Biomass feedstocks could be classified statistically into those suitable for biomass liquefaction and those unsuitable. The difference depended strongly on fat content in the particular biomass feedstocks. Energy balance for the liquefaction process was also estimated.