Effects of biomass fast pyrolysis key parameters on yields and distributions of products

Sawdust fast pyrolysis experiments were conducted in a fluidized bed reactor at a biomass feed rate of 0.80～2.00 kg·h^-1. The effects of process conditions, like fluidized bed reactor temperature, feed size and vapor residence time on the product yields were studied. When reactor temperatures were varied from 450℃ to 600℃, a maximum bio-oil yield of 53.33%wt was achieved at 500℃ with a char and gaseous yields of 8.97 %wt and 37.70%wt respectively. The particle size of sawdust varied in the range of 0～0.90 mm. The yield of bio-oil was maximum (58.23%wt of biomass feed) for the particle size of 0.45～0.60 mm with a char yield of 8.23%wt. Vapor residence times were ranged from 0.80 to 1.50 s at temperature of 500℃ with a particle size less than 0.20 mm. A maximum bio-oil yield of 62.60%wt was achieved at 500℃ when the vapor residence time was held constant at 0.80 s. However, at the longer residence time(1.50 s), bio-oil yield was slightly lower. Bio-oil is a miscible mixture of polar organics with water. The results showed the potential of sawdust fast pyrolysis for liquid hydrocarbon fuels production.