Effects of pulsating air flow in fluid bed agglomeration of starch particles

• Agglomeration of native cassava starch and cornstarch particles in a pulsed-fluid bed.
• Evaluation of powder bulk properties with granulation.
• Study of fluid dynamics behavior of cohesive food powders.
• Characterization of shape parameters with particle enlargement.
• Population balance modeling and evaluation of aggregation kernel constant.

Fluid bed agglomeration is commonly used to improve the instant properties and flowability of cohesive food powders. However, fluidization of cohesive particles is characterized by cracks and channeling, but air pulsation systems can be attached to the fluid bed in order to improve bed homogeneity. The aim of this study was to investigate the influence of air pulsation frequencies, at (0, 5, 10 and 15) Hz, in fluid bed agglomeration of cassava starch and cornstarch particles. The particles size increased with agglomeration, resulting in the decreasing of wetting time and higher flowability. The solving of Population Balance Equations achieved the experimental aggregation kernel constants. The pulsation of (5 and 10) Hz resulted in the higher agglomeration rates, for both cassava and cornstarch study, respectively. The evaluation of the experimental PBE kernel constants were useful to measure the aggregation rate and to compare the performance of a fluid bed granulator.