Comparative study of fast pyrolysis in a tubular reactor for various biomass materials

Four types of biomass including palm kernel cake, waste coffee, oak wood and pine wood were pyrolyzed in a tubular reactor using nitrogen as a sweep gas. The activation energy of pyrolysis corresponding to each biomass was determined using thermogravimetric analysis. For each type of biomass, the effect of temperature and nitrogen flow rate on pyrolysis were also studied. The product yield of pyrolysis indicated that the higher the composition of Klason lignin, the higher the bio-oil yield and the lower the gas yield. The pyrolysis was preferential for bio-oil at 550°C while for gas product at 750°C. At 550°C, the pyrolysis of palm kernel cake, a biomass with the highest content of lignin (27.4 wt%), had the maximum bio-oil and minimum gas yield at 58.9 wt% and 15.7 wt% respectively. Meanwhile, at 750°C, pine wood with the lowest content of lignin (16 wt%) was disintegrated to form the maximum gas yield at 67.3 wt% and minimum bio-oil yield at 16.4 wt%. The composition of gas product from pyrolyzing palm kernel cake, waste coffee and pine wood was rather similar, in which largely consisted of C1-C3 alkanes, ethylene, CO, and CO2.