FCC提升管内气液固三相流动的数值模拟研究

Numerical Simulation of Gas-Solid-Liquid Three Phase Flow in FCC Riser

采用Fluent软件,耦合提升管内油气、雾滴和催化剂间的动量、热量和质量传递,建立了气液固三相作用模型。采用此模型对FCC提升管进料雾滴的气化过程以及气液固三相流动进行了模拟研究,考察了雾滴在提升管内的气化时间,以及不同碰撞几率下各相的体积分数分布、液固传质速率和催化剂上吸附的液相含量。结果表明,非气化组分的气化时间很短,对气液固三相流动的影响很小,但其在催化剂上的大量吸附会降低催化剂活性,最终影响FCC反应效果。

Using Fluent software,coupling the momentum,heat and mass transfer models of oil gas,droplets and catalysts,a gas-liquid-solid flow model was proposed.Based on the above model,the gasification time of the liquid droplet,the liquid and solid volume fraction distributions,the liquid and solid mass transfer rates,as well as the contents of liquid adsorbed in catalysts were analyzed.The results showed that the gasification time of liquid droplets is very short.The existence of high-boiling-point components has little effect on flow behaviours.However,the mass transfer of liquid to solid phase decreases the activity of catalysts,thus impact the final FCC reaction effects.