Effect of Gas Velocity and Bed Mass on Liquid Minimum Fluidization Velocity in a three -phase Fluidized Bed with Cylinderical Particles

Abstract

Three-phase fluidized beds have been applied successfully in the bio-oxidation process for wastewater treatment in which various low to moderate density solid particles of different shape and size are used as cell support. Ceramic raschig ring possess moderate density and high surface area due to its hollow cylindrical structure. Thus can be used as solid support for microorganisms, where higher mass transfer rate can be achieved. In this study the hydrodynamic characteristics viz. the pressure drop, bed expansion and liquid minimum fluidization velocity of a co-current gas-liquid-solid three-phase fluidized bed have been studied using liquid as the continuous phase and gas as the discontinuous phase. Bed pressure measurements have been made to predict the minimum liquid fluidization velocity and the effect of gas velocity and bed mass on it has been studied.