Modeling and optimization of continuous crystallization using a continuous oscillatory baffled crystallizer

Abstract

In this paper, the continuous crystallization process with a continuous oscillatory baffled crystallizer (COBC) has been studied. The control objective is to obtain the desired crystal size distribution (CSD) from this process. A population balance equation (PBE) is derived by combining the crystallization mechanism and the COBC structure characteristics. The solution of the PBE can be used to characterize the CSD of any given position within the crystallizer. Constant supersaturation control has been chosen to control the crystallization process and the optimal supersaturation value is obtained by minimizing the error between the desired and the calculated CSDs, which leads to the desired cooling temperature profile along the crystallizer. The inlet temperature of the cooling water of the jacketed glass tubes is calculated based on energy balance which ensures that the solution temperature along the crystallizer follows the desired cooling temperature curve. A set of simulations has been provided to demonstrate the effectiveness of proposed method.