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In this paper, the integrated characteristics of a fluidized bed combining a distributed entrained flow bed in a new reactor, and the oxygen enriched gasification performance of biomass in the integrated reactor were studied numerically on the basis of experiments. A 3D numerical model was established by FLUENT and Eulerian-Lagrangian method was selected to solve the model. Simulation results show the integrated characteristics, where the lower-stage of the reactor performs the characteristics of distributed entrained flow, and the upper-stage shows fluidized bed characteristics by fluid upward returning. In addition, the influencing factors of oxygen-carbon mass ratio (O/C) and oxygen concentration of gasification agent, were studied based on experiment. The results show that as the O/C increases, the concentrations of H2 and CO2 in the syngas gradually decreases but the CO concentration remains stable. The effect of O2 concentration on syngas composition is related to its O/C. The concentrations of CO and CO2 rise as the O2 concentration increases. However, when the O/C is between 0.35 and 0.55, as the oxygen concentration increases, the H2 concentration shows a trend of firstly increase and then decrease. All the numerical and experimental results are in good agreement. |
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