Spatial reaction engineering approach as an alternative for nonequilibrium multiphase mass‐transfer model for drying of food and biological materials

Abstract

in Wiley Online Library (wileyonlinelibrary.com).Drying is a complex process which involves simultaneous heat and mass transfer. Complicated structure and heterogeneity of food and biological materials add to the complexity of drying. Drying models are important for improving dryer design and for evaluating dryer performance. The lumped reaction engineering approach (L-REA) has been shown to be an accurate and robust alternative for cost-effective simulations of challenging drying systems. However, more insightful physics has to be shown spatially. In this study, the REA is coupled with the standard mechanistic drying models to yield the spatial-REA (S-REA) as nonequilibrium multiphase mass-transfer model. The S-REA consists of a system of equations of conservation with the REA representing the local evaporation and wetting rate. Results of the modeling using the S-REA match well with the experimental data reported previously. This is the first comprehensive REA approach to model the profiles of water vapor concentration during drying of food and biological materials. This study indicates that the S-REA can be an accurate nonequilibrium multiphase mass-transfer model with appropriate account of the local evaporation rate. The overall REA concept is expected to contribute substantially for better and cost-effective representation of transport phenomena of drying process.

A continuum‐approach modeling of surface composition and ternary component distribution inside low fat milk emulsions during single droplet drying

“…At the end of drying, the gradient was not noticeable which indicated that the equilibrium condition was nearly attained. Similar profiles were also observed during drying modelled using the spatial reaction engineering approach (S-REA) 25,28,34 . For the temperature profiles, as shown in Figure S2, there was no noticeable gradient of temperature during drying.…”

“…For modelling water removal from the droplet during drying, the mass balance of water can be represented as 25 : The heat balance can be written as 25 :…”

“…The reaction engineering approach (REA) was applied to describe the drying kinetics of several formulations of dairy droplets 19,24 . The spatial reaction engineering approach (S-REA) was further implemented to describe several challenging cases of heat and mass transfer [25][26][27][28][29] . Although surface composition plays a vital role in determining the powder functionality, only a few modelling studies have been attempted to predict the surface composition.…”

S-REA (spatial reaction engineering approach): An effective approach to model drying, baking and water vapor sorption processes

“…2-7 show that the S-REA is accurate to model drying of non-food materials. Previously, the S-REA was implemented to describe drying of food and biological materials and the results of modeling match very well with the experimental data (Putranto and Chen, 2013a). The accuracy of the S-REA may be because of the applicability of the REA to describe the local evaporation/condensation rate.…”

On the Influence of Particles Characteristics on Moisture Diffusivity during Drying of Granular Porous Media

“…Among a series of equations tested, the one that provides a value consistent with the literature is that proposed by Putrano and Chen [8]:…”