Modeling the Growth Kinetics of Fluidized-Bed Spray Granulation

Fluidized‐bed spray granulation is used to produce porous granular particles from suspensions, solutions, and melts. In this work, the adapted two‐fluid model approach is used to simulate the fluid dynamics in the fluidized bed, and a simplified direct quadrature method of moments is adopted to mimic the full particle size distribution. The size‐dependent growth kinetics is obtained by computational fluid dynamics simulation for short process times from the modeling of drop deposition on the particles. This kinetics is used in the population balance equation to predict the evolution of the full particle size distribution for long process times. Such a multiscale approach allows for a description of continuous granulation processes. In this investigation, a coupled computational fluid dynamics (CFD) and population balance equation (PBE) approach has been used to simulate the growth of polydisperse particles in a fluidized‐bed spray granulation process. The growth kinetics is used in the PBE to solve the development of the particle size distribution for a long process time without considering the fluid dynamics.