Influences of temperature arrangement on hydrogen production during two-stage gasification process

Abstract

The effects of temperatures of the first and second stages, equivalence ratio (ER), and steam/biomass (S/B) ratio on the formation of syngas during two-stage gasification were investigated. Experiments conducted with the first and second stages performed at different temperatures showed that the total H2 production rate was optimal when the first and second stages were both operated at 900 °C. The amount of H2 produced increased from 28.8 mol.% in the first stage to 37.4 mol.% in the second stage. When the temperatures of the first and second stages were 500 and 900 °C, respectively, the total H2 production rate increased from 23.9 mol.% in the first stage to 36.8 mol.% in the second stage. Hence, even if the first stage is operated at a lower temperature, leading to lower H2 production rates, operating the second stage at a higher temperature will always help to improve the H2 production rate.