膜过程强化和组件放大的CFD应用

CFD applied to membrane process intensification and module scale-up

膜分离作为21世纪最具前景的高新技术之一,已广泛应用于化工、环境、生物、医药、电子等领域.然而,能耗高、产量低和寿命短三大问题始终制约着膜组件的应用.寻求合适的方法研究膜组件非理想流动下的传递过程,可用于指导膜组件放大和性能提升.计算流体力学(CFD)作为继量纲分析法和模型法之后一种新兴的化学工程研究方法,已被广泛应用于膜分离领域.本文以膜单元为对象的过程强化研究和以组件为对象的设备放大研究两方面综述了膜分离CFD模拟的最新进展.前者归纳了中空纤维膜、卷式膜和平板膜CFD研究所采用的模型和处理方法;后者总结了中空纤维膜组件三维CFD模拟的简化策略.然后提出两类CFD研究应着重发展的方向.最后根据CFD和膜技术的发展路线,预测两者在未来的结合将更加紧密.

Membrane separation has found numerous applications in fields such as chemical engineering,environmental science,biology,and the pharmaceutical and electronic industries.However,high energy consumption,low productivity,and short lifespan still present severe challenges,which restrict the practical application of membrane modules.To achieve scale-up of a membrane module with high performance,appropriate methods are needed to analyze the transport phenomena occurring under nonideal hydrodynamic conditions in the module.In addition to traditional dimensional analysis and modeling,computational fluid dynamics（CFD）has emerged as a new method which has been widely used in studies of membrane separation.This study reviews the recent progress in membrane-based CFD research from two aspects：process intensification studies based on membrane cells and scale-up studies based on membrane modules.The former part introduces the models and methodologies adopted during the CFD simulation of the processes occurring in hollow fiber membranes,spiral wound membranes,and flat membranes.The latter part summarizes various simplification strategies concerning the three-dimensional CFD simulation of the processes occurring in hollow fiber membrane modules.Areas that deserve to be focused on are proposed for the two categories of CFD studies.We predict that a closer combination between CFD and membrane technology will occur in the future.