Process conditions sensitive (PCS) thin-layer mathematical model of hot air convective drying

Abstract

In this work, a model sensitive to changes of process parameters such as temperature, air velocity, air initial relative humidity, and wet material layer thickness has been developed and verified by two different experimental methods. A laboratory convective batch dryer was used to measure drying behavior of 11 types of products at various process conditions to determine the model parameters. An independent solar drying system was used to experimentally verify the model. The model can predict drying kinetics at any point within a defined range of process conditions: model parameters were determined for temperature range of 40–50 °C, air velocity of 0.6–1.2 m/s, initial air relative humidity of 27–45%, and layer thickness of 4–12 mm. However, the model was verified also for extrapolated air velocity and humidity with good agreement between experimental and model data despite the use of a different independent experimental system.