Mathematical modeling of moisture evaporation in co-current foam spray drying

Abstract

Two models of foam drying are presented in the paper: single droplet drying and perfect mixing of phases spray drying models to describe mechanism of drying of droplet containing bubble. Analysis of drying curves shows that in constant drying rate period and in the falling drying rate period, evaporation rate decreases due to particle shrinkage and increasing of resistance of moisture diffusion inside the solid crust. Increase of gas pressure in the bubble might cause particle breakage. Slight differences between theoretical and experimental results caused by disregarding broken particles in the simulations proves accuracy of the developed model. Keywords: spray drying, modeling, foamed materials, particle morphology