INFLUENCE OF THE CONICAL SECTION GEOMETRY ON THE HYDRODYNAMICS OF SHALLOW SPOUTED BEDS

The hydrodynamics of shallow spouted beds and a comparison with the hy drodynamics of conventional spouted beds were studied on a pilot plant scale unit by operating under a wide range of geometric characteristi cs of the contactor-particle system (base angle, inlet diameter to con tactor base diameter ratio, inlet diameter to particle diameter ratio, inlet diameter to column diameter ratio); the ranges of these paramet ers in which stable operation is possible were delimited. The peculiar hydrodynamic behaviour of shallow spouted beds is attributed to the i nfluence of the conical section of the base, which is an important fra ction of the bed. Assuming that the shallow spouted beds are made up o f the conical section of the base and the posterior cylindrical sectio n, correlations are proposed for the calculation of the minimum spouti ng velocity, maximum pressure drop of the bed, operating pressure drop and the bed voidage corresponding to minimum spouting in shallow spou ted beds; these are a combination of the correlations proposed in prev ious papers for totally conical and totally cylindrical contactors.