Modeling and Simulation for Feasibility Study of Taylor-Couette Crystallizer as Crystal Seed Manufacturing System

Taylor-Couette reactor (TCR) consists of two concentric cylinders with small gap and typically the inner cylinder is rotating. In the concentric gap of the reactor, special patterns of flow are generated. Taylor-Couette flow has a Taylor vortex that is characterized by axisymmetric toroidal vortices. This phenomenon was first discovered by Taylor in 1923. Recently, the Taylor-Couette reactor has been used as a crystallizer and phase-transformation device. For example, the phase transformation of Guanosine 5-monophosphate (GMP) investigated by using the drowning-out crystallization method. Also, the Taylor-Couette reactor is used as a crystallization device experimentally and numerically, in which the fine particles are classified. In our previous work, the dynamic characteristics of Taylor-Couette flow and the possibility of particle classification were investigated numerically and experimentally for the case of vertical TCR in a continuous system. However, none of these studies involves the crystallization modeling due to the difficulty of simultaneous modeling of fluid dynamics and PBE.In the present study, a CFD-PBE model is developed for verifying the performance of continuous TCR as crystallizer and classifier. A saturated ammonium sulfate solution is used as the sample substance. This CFD-PBE model is based on the Eulerian multi-phase model to describe the liquid-solid two phase flow and the discrete method PBE model including nucleation and growth kinetics. Since the PSD of TCR is much narrower than CSTR, TCR could be adjusted as crystallizer for seed manufacturing.