再分布板对环隙气升式反应器内多相流动的影响

摘要

To investigate the effect of redistributors on the multiphase flows in the scale-up of airlift reactors, the Euler-Euler two fluid model are adopted to simulate the influence of redistributors on gas holdups, liquid circulation velocity and the distribution of solid concentration. The Computational Fluid Dynamics (CFD) model shows excellent agreement with the measured data on total gas holdup. This research demonstrates that the height of redistributors increasing can make gas holdup in the bubble riser non-monotone trend and promote the solid concentration in the downcomer, however, has little effect on the total gas holdups and liquid circulation velocity. Therefore, the design of redistributors have been optimized by combining CFD simulation and experiment, which is benefit for strengthening the processes of multiphase flow, mass-transfer, reactions in the airlift reactors.%为了考察环流反应器放大过程中再分布板对其内部多相流动的影响，采用噢啦双流体模型模拟了再分布板不同高度的布置对环流反应器内气含率，循环液速，固体颗粒分布等参数的影响，并与部分冷模实验结果进行了比较，两者结果一致。结果表明，再分布板高度的增加会使气升反应区内气含率呈现先增后减的趋势，并导致导流管内的固含率上升。此外，不同高度的再分布对环流反应器内整体气含率及循环液速的影响不大。结合CFD模拟和实验结果，优化了环流反应器内再分布板的设计，从而为实现强化环隙气升式环流反应器内多相流动，传递，反应等过程提供了一定的指导意义。