Experimental Study on Vibro-Fluidized Bed Drying

Vibro-fluidized bed drying is commonly encountered in several industries in order to reduce the moisture content in products. Drying is a continuously evolving process where the particle and gas properties change over time. The particle mass reduction and the gas moisture saturation are key factors that influence the process properties such as the fluidization behavior. Conversely, the changing fluidization behavior influences the mass and heat transfer characteristics. Vibration enhances the fluidization characteristics, hence solids drying is improved compared to static fluidized beds.

In this study, experiments in a pseudo-2D vibro-fluidized bed setup are performed in order to better understand the improved solids drying behavior in vibro-fluidized beds. A coupled Particle Image Velocimetry - Infrared Thermography technique is employed to characterize the local solids velocity and temperature fields. In the first part, the effect of mechanical vibration on monodisperse solids drying is discussed. The second part focuses on the extension to binary and ternary mixtures where a machine learning algorithm is applied to characterize the size-based mixing and segregation dynamics. It is found that size-based segregation is suppressed under the influence of mechanical vibration.