Stochastic-Deterministic Population Balance Modeling and Simulation of a Fluidized Bed Crystallizer Experiment

Abstract The crystallization of potassium aluminum sulfate dodecahydrate (potash alum) in a fluidized bed crystallizer is studied both with experiments and simulations. A population balance system with three spatial coordinates and one internal coordinate (mass) is utilized as our model. The simulations are performed with a stochastic-deterministic method with novel extensions, where the fluid dynamics of the crystallizer (flow field, temperature, concentration) are solved deterministically and the particles are simulated with a stochastic method. In experiments of 30 min duration, the average crystal diameter increases by growth and agglomeration from about 130 μm to 210 μm. This observation agrees qualitatively well with our simulation results. A quantitative difference between simulation and experiment leaves room for future improvements in modeling.