Modelling and optimization of fuel conversion in an indirect bubbling fluidized bed gasifier

摘要: The aim of this thesis was to improve the fuel conversion in Chalmers bubbling fluidized bed (BFB) gasifier. A mathematical model has been developed and experiments a fluid-dynamically scaled reactor have conducted. To increase use horizontal tubes partitioning walls studied. The is 2-dimensional accounts for fluid dynamics, heat transfer conversion. also used determining dispersion coefficient, D, velocity slip factor, α, from experimental data. Lateral material mixing evaluated through an indirect method by tracing iron powder material. lateral direct using digital image analysis. new investigate convective flow influence evaluated. easy, quick robust, thus showing great potential. The resulting up-scaled values coefficients were range 2.44 - 4.77·10-3 2.15 6.17·10-3 m2/s particles. at tube banks particles 1.08 1.34·10-3 and. 1.07 1.79·10-3 respectively. This shows that reduced around 70% whereas had little impact on modelled char Tube fuel, with 40% 100% thereby increasing residence time fuel. Through simulations tuned different arrangements internals, it found main parameter improved increased 6% without internals 22% when two thirds beds covered properly placed bank.