Minimum fluidization velocities in beds of mixed solids

The fluidization behaviour of a bed of solids of mixed sizes and/or densities indicates that for a range of velocities between u bf (the velocity of beginning of fluidization) and u tf (the velocity of complete fluidization), such a bed is only partially fluidized. The phase diagrams of these systems show that the phenomenon is analogous to the fractional crystallization of a multicomponent solution and it can find use in selective classification of solids. In the present work, data on u bf and u tf for liquid fluidized beds of two, three, four and five component mixtures have been processed along with those reported earlier on gas‐solid systems, to yield useful correlations for their prediction.