Distinguishing Liquid Transport Patterns during the Fluidization of Wet Particles with Bed Expansion Behaviors

Abstract

The liquid transport pattern in a fluidized bed of wet particles influences the global fluidization dynamics. This paper proposed a method for distinguishing liquid transport patterns according to the bed expansion behaviors at incipient fluidization. The results show that the average bed expansion ratio increases first and then decreases with increasing ratio of liquid to solid (L/S ratio), corresponding to the free-liquid regime and trapped-liquid regime, respectively. The L/S ratio at the largest expansion ratio, Λc, is the critical value distinguishing both regimes. The critical L/S ratio increases with particle diameter while decreases with the liquid surface tension. The liquid viscosity has negligible impacts on the bed expansion and the critical L/S ratio. Finally, a regime map was drawn combining the bond number Bo and L/S ratio, and a correlation between Λc and Bo was fitted: Λc = −Bo/10,000 + 0.0111. This may help choose operating parameters according to the desired liquid transport pattern.

Estimation of the Fluidization Behavior of Nonspherical Wet Particles with Liquid Transfer

“…The liquid presence in a wet-particle system alters the particle collision owing to the introduction of additional viscous and capillary forces. , Buck et al proposed a force balance model to investigate the collision dynamics of wet particles. It was pointed out that the normal restitution coefficient greatly depended on the properties of the liquid layer.…”