Intensification design of green crystallization separation: Process optimization and technology coupling

Abstract

This work designs different process intensification trajectories in the layer melt crystallization (LMC) to improve the separation efficiency. Parameters of distribution coefficient, interfacial solute distribution factor, and mass transfer coefficient are proposed to figure out the intrinsic correlations of technical variables and target parameters. The first proposal strategy is the optimization of the operating curve, divided into cooling process regulation and temperature cycling strategy. Both techniques can eliminate the fine crystals, thus favoring the crystal growth and reducing the impurities' adsorption. Next is the incorporation of the stirring intensification technique into the LMC. The problem of burst nucleation is restricted significantly through the suitable design of the stirring parameters. At last, a coupling technique that combines suspension and LMC is designed. The crystal seeds generated from the suspension melt can flow into the tubular crystallizer and act as the sites for crystal growth. This coupling technique exhibits excellent separation efficiency and huge potential in industrial production. The proposals for the further development of the LMC technique are given.