Effect of louver baffles installation on hydrodynamics of bubbling fluidization in biomass gasifier

Abstract

AbstractBiomass gasification by a bubbling bed gasifier has been a promising process to produce fuels from biomass. However, the performance is limited by gas aggregation in the gasifier. In this study, CFD simulations were used to investigate hydrodynamics in bubbling bed gasifiers installed with multilayer louver baffles to understand the roles of baffles on different aspects including gas aggregation, biomass-bed mixing, gas-biomass contact, and pressure drop. The designed baffles could reduce the gas aggregation particularly when the biomass is fed at the middle of the baffle zone. The baffles could enhance the biomass-bed mixing and the gas-biomass contact throughout the bed except near the biomass inlet. The installation of baffles would not significantly affect the overall pressure drop but slightly affect at the mid-level of the bed. For the system in this study, the baffled gasifier with biomass feeding at the middle of the baffled zone and the gas inlet velocity of 0.7 m/s could provide the best performance in term of hydrodynamics.