(103c) Reducing Segregation By Wet Granulation

Authors: 
Fan, Y., The Dow Chemical Company
Hook, B. D., The Dow Chemical Company
Jacob, K., The Dow Chemical Company
In various industrial applications, powder additives are regularly added to bulk solid products to achieve desired functionality in subsequent processes or final products. However, these powder additives often have different particle sizes or size distributions from the main components (bulk solid products), which can result in segregation during solids handling, transportation or packaging. Segregation between the additives and the bulk solid products can decrease the process efficiency or cause product quality problems. One approach to minimize or even eliminate segregation is wet granulation. The wet granulation process aims to produce granulated additives having similar particle size distributions to the bulk solids so that size segregation can be prevented.

In this research, we present an example of an industrial application where the strong segregation tendency between the powder additive and the bulk solid products can be minimized by a wet granulation process. First, segregation of the dry mixture of the powder additive and bulk solid product was quantified by both experimental and recently developed theoretical approaches [1]. Then, a granulation process was developed and optimized to produce additive granulates with similar particle size distribution to the bulk solid product. Finally, theoretical calculations on the segregation tendency for the mixture of the granulated additives and bulk solid product were performed, showing that segregation is significantly reduced and the homogeneity of the mixture is preserved.

[1]

Y. Fan, C. Schlick, P. Umbanhowar, J. Ottino and R. Lueptow, "Modelling size segregation of granular materials: the roles of segregation, advection and diffusion," Journal of Fluid Mechanics, vol. 741, pp. 252-279, 2014.