Study of liquid retention in fixed-bed reactors with upward flow of gas and liquid

A literature survey of the measurement techniques for the determination of liquid retention in cocurrent upward gas and liquid flow in fixed-bed reactors is presented. A number of these techniques were used in this work in columns of different diameters (Dc = 0.05 m, 0.10 m, and 0.15 m). Porous alumina particles of two different diameters (dp = 0.002 m and 0.0028 m) with both nonfoaming (water, cyclohexane, heptane, and propanol) and foaming liquids (kerosene, LCO, and diesel fuel) have been investigated. The gas used was either air or N[sub 2]. The methods investigated include volumetry, gravimetry, gammametry, and determination of residence-time distribution by tracer technique. A simple correlation for the prediction of total gas and liquid retention for bubble and pulsed flow is proposed and verified.