Pressure Drop and Bed Expansion in a Mobile Bed

Abstract

The pressure drop, ΔP and the expanded bed height, H in mobile beds have been related to states of fluidized packings. The bed is operated best under the conditions such that the pressure drop across the bed is constant and independent of gas velocities.Correlations of ΔP and H with operating conditions are presented.1. The pressure drop, ΔP is calculated by the following equation.ΔP=ρP/ρLHP+εSLHSwhere ρP, ρL, are densities of packing and liquid, and Hs is the static bed height.2. The expanded bed height, H could be calculated by the following equation.H/HS= (1+εSL-εSP) / (1-εG) where εSL, εSP are the holdup of liquid based on the static bed height and the void fraction in the dry packed bed, respectively, and εG is the gas holdup based on the expanded bed height.