(87e) Computational Fluid Dynamics Modeling of Mixing and Reaction of High-Viscosity Liquids in a Continuous Flow Reactor
It is well known that mixing is affected by material properties such as density, viscosity and surface tension; by operating conditions such as pressure and temperature; and by flow conditions and geometries. Chemical reactions between the mixing liquids further affects the mixing patterns in the reactor by varying the properties and local temperatures at different points in the fluid. However, while mixing has been studied for many decades, the detailed mixing behavior of such complex systems is still not fully understood, yet critical for reactor design and operation.
In the present study, we present computational fluid dynamics (CFD) simulations aimed towards understanding the mixing behavior of highly viscous liquids (polymeric anhydrides and amines) that are typically used in manufacturing dispersants via amination of the anhydride. Beyond a systematic analysis of the mixing behavior inside a continuous flow tubular reactor as a function of some of the variables listed above, we will discuss the use of appropriate metrics to study mixing, such as coefficient of variation, exposure and reaction conversion. Furthermore, the effect of different inlet geometriesâranging from co-axial flows to spray-type feed configurationsâas well as the use of in-line static mixers will be discussed. Key results from CFD simulations are validated against laboratory experiments with non-reactive flow visualization as well as reactive tubular reactor experiments. The results of this study are being used to assist optimal design of experiments and scaling up to pilot-plant scale.