High-shear vs. Fluid-bed Granulation Process of Dolomite: Process Modeling

High-shear and fluid-bed processes were used for granulation of dolomite powder into agrochemical product. In this paper, comparative study of the granulation process focuses on the observation of granule size distribution (GSD). Considerable difference between high-shear and fluid-bed GSDs is analyzed with process kinetics. Simulation of dynamic development of GSD is achieved with application of a 1-D discretized population balance and Equi-Partition of Kinetic Energy (EKE) coalescence model. The used approach indicates for both processes (high-shear and fluid-bed granulation) the presence of coalescence growth as a dominant mechanism in the dolomite granulation process. Deviations between simulated and real GSDs signify the probable existence of other granulation mechanism(s). A posteriori approach by the integral method was used for coalescence rate constant estimation. The generated kinetic considerations represent a valuable step towards a comprehensive perspective of dolomite granulation and implementing the acquired knowledge in real-life agrochemical granulation.