A comprehensive model has been developed to couple CFD with the population balance equation (PBE) for a flat sheet membrane-assisted antisolvent crystallization (FS-MAAC) process. The model accurately depicts the fluid dynamics, mass transfer, heat transfer and crystal size distribution (CSD) in the FS-MAAC crystallizer. The crystallization system considered was to produce α-form crystals of glycine. The model investigates the effects of different parameters, such as the velocities of the crystallizing and antisolvent solutions, antisolvent composition, temperature, and gravity. A good agreement was observed between the simulation results and experimental data for the α-form crystals of glycine. The simulation results show a steady-state antisolvent concentration profile in the liquid layer and varied only in the z-direction. Regardless of the variations in the velocity of either the antisolvent solution or the crystallizing solution, the CSD remained narrow, with mean crystal sizes ranging from 27 to 40 μm. Furthermore, increasing mass transfer through the antisolvent transmembrane flux leads to a narrower CSD. Slower antisolvent permeation rates at higher temperatures also promote crystal growth. Also, a narrow CSD is maintained regardless of the initial circulation position of the antisolvent solution. In conclusion, membrane antisolvent crystallization provides a reliable and consistent solution for obtaining crystals with desired CSD under optimal operating conditions.

中文翻译：

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平板膜辅助反溶剂结晶的 CFD 群体平衡建模


我们开发了一个综合模型，将 CFD 与群体平衡方程 (PBE) 结合起来，用于平板膜辅助反溶剂结晶 (FS-MAAC) 工艺。该模型准确地描述了 FS-MAAC 结晶器中的流体动力学、传质、传热和晶体尺寸分布 (CSD)。所考虑的结晶系统是产生甘氨酸的α型晶体。该模型研究了不同参数的影响，例如结晶和反溶剂溶液的速度、反溶剂成分、温度和重力。对于甘氨酸的 α 型晶体，模拟结果与实验数据之间观察到良好的一致性。模拟结果显示了液体层中的稳态反溶剂浓度分布，并且仅在 z 方向上变化。无论反溶剂溶液或结晶溶液的速度如何变化，CSD 仍然很窄，平均晶体尺寸范围为 27 至 40 μm。此外，通过反溶剂跨膜通量增加传质导致更窄的 CSD。较高温度下较慢的反溶剂渗透速率也促进晶体生长。此外，无论反溶剂溶液的初始循环位置如何，都会保持狭窄的 CSD。总之，膜反溶剂结晶为在最佳操作条件下获得具有所需 CSD 的晶体提供了可靠且一致的解决方案。