Centrifugal Settling of Polydisperse Suspensions with a Continuous Particle Size Distribution: A Generalized Kinetic Description

The settling of a polydisperse suspension with a continuous particle size distribution (PSD) can be modeled by an equation of the generalized kinetic theory, which represents the limit case of a system of conservation laws for a finite number of size classes. A previous model of gravity settling of such a mixture is extended to settling in a rotating tube or basket centrifuge. A numerical scheme to approximate solutions of the generalized kinetic equation is defined and simulations are presented, illustrating the formation of sediment and the effect of various centrifuge geometries. In particular, the model predicts the radial variation of the composition of the sediment forming at the outer wall.