Thermo-chemical conversion of biomass using Dual Fluidized Bed (DFB) gasifier is proven to be a promising way for the production of H₂ rich syngas. In the present work, the hydrodynamics in the DFB gasifier is investigated experimentally and with Computation Fluid Dynamics (CFD) at cold flow conditions. Three-dimensional Eulerian-Eulerian multi-phase model combined with the kinetic theory for the granular phase has been applied to investigate unsteady-state behaviours of a DFB gasifier. The developed CFD model is validated with experimentally obtained pressure distributions across the riser. The model prediction shows deviation from experimental results (10-14%), which are mainly due to the Gidaspow drag model over predicting drag force. Simulation results are presented in terms of the pressure profile, solids hold-up and solid circulation rate.

使用双流化床（DFB）气化炉对生物质进行热化学转化已被证明是生产H ₂的有前途的方法丰富的合成气。在当前的工作中，DFB气化炉中的流体动力学是在冷流条件下通过实验和计算流体动力学（CFD）进行的。三维欧拉-欧拉多相模型与动力学理论相结合的颗粒相已被用于研究DFB气化炉的非稳态行为。通过实验获得的提升管上的压力分布验证了开发的CFD模型。模型预测显示出与实验结果的偏差（10-14％），这主要是由于Gidaspow阻力模型过度预测了阻力。模拟结果以压力分布，固体滞留率和固体循环速率表示。