Bio-oil gasification using air - Steam as gasifying agents in an entrained flow gasifier

The production of gas via bio-oil gasification, which would act as a bridge between bio-oil and transportation fuels, has been increasingly concerned. Bio-oil gasification was performed by using air - steam as gasifying agents. The effects of two important influential factors (steam to bio-oil ratio and gasifier temperature) on the quality of the product gas (gas composition, H2: CO, CO: CO2, tar content, degree of oxidation and heating value) and the gasification process performance (gas yield, steam decomposition, cold gas efficiency, and carbon conversion efficiency) were investigated. The results showed that the impact of the steam to bio-oil on the gas quality and gasification performance had an optimum point (steam to bio-oil ratio = 2.5); However, the influence of the gasifying temperature on both of them demonstrated a sole monotone function. The hydrogen concentration in the product gas reached a maximum of 30.0 vol.% and the ratio of H2/CO basically remained 2.0 over a range of steam to bio-oil ratio from 2.5 to 4.0. The product gas with such a H2/CO ratio is expected to be applied in CO hydrogenation processes, such as Co-catalyzed Fischer-Tropsch synthesis (FTS). Moreover, the product gas is also suitable for the generation of electricity.