Pyrolysis characteristics of pine biomass in a powder-particle fluidized bed

To investigate the fluidized characteristic of powder particle fluidized bed (PPFB), the experiment of cold model fluidized bed was carried out. The results show that fluidization of PPFB could be maintained when gas velocity is in an appropriate range. Pyrolysis and catalytic pyrolysis of pine biomass was also investigated using the PPFB. It was found that there is a rapid release zone for the volatile during biomass pyrolysis, about 92% of the volatile matter of pine is released at 723 K. The total yield of inorganic gas (IOG), hydrocarbon gas (HCG) and hydrocarbon liquid (HCL) is only 3.1%at 773 K. The yields of IOG, HCG and HCL increase with the increase of pyrolysis temperature. The total yields of IOG, HCG and HCL reach 58.7% at 1 173 K, and the pyrolysis product is almost CO. CoMo-B catalyst greatly promotes the secondary reactions of the primary products of catalytic hydropyrolysis. At 863 K the yield of light aromatic hydrocarbons (benzene, toluene, xylene and naphthalene) is 6.3%, which is 2 times higher than that by using SiO₂ at 1 173 K.