Characteristics of Bio-oil from the Fast Pyrolysis of Elephant Grass (Pennisetum purpureum Schumach) in a Fluidized Bed Reactor

Bio-oil was obtained from the fast pyrolysis of elephant grass in a semi-pilot scale pyrolysis plant equipped with a 40 kg/h fluidized bed reactor. The temperature varied between 480 and 520°C. The biomass (moisture of 10%) was fed with a rate between 20 and 35 kg/h. Approximately 4.5 kg of sand was used as fluidizing agent. The pyrolytic oil was analyzed for the contents of carbon, hydrogen and nitrogen and sulfur. Water content, acidity, pH, viscosity at 40°C, density and higher heating value were also determined. Chromatographic analysis showed that it was composed mostly of acetic acid, syringol, vinyl-phenol, guaiacol and hexanoic acid. Main results are used to compare the influence of different configurations of a gas-washing column and vapor condensation system on the properties of the bio-oil.