Collect. Czech. Chem. Commun. 1991, 56, 619-635

Design and scale-up of Venturi-tube gas distributors for bubble column reactors

Jindřich Zahradník and Milan Rylek

Institute of Chemical Process Fundamentals, Czechoslovak Academy of Sciences, Prague 6-Suchdol


General principles of ejector distributors performance are surveyed and demonstrated for two particular cases of Venturi tubes commonly employed for gas dispersion in tower reactors with forced liquid circulation. Design recommendations for the two types of Venturi-tube gas distributors are presented and a general method is outlined for ejector distributors scale-up, based on the decisive effect of energy dissipation rate on the distributors performance. As an illustration, the specific case of Venturi-tube gas distributor design for an industrial reactor for catalytic hydrogenation of rape-seed oil is treated in detail. The procedure included design of a small-scale laboratory reactor for kinetic experiments at real process conditions (scale-down step) and subsequent ejector distributor scale up to dimensions corresponding to the industrial reactor (vessel diameter 1.6 m, effective reactor volume ~ 5 m3). Comparison with other modes of gas dispersion proved superiority of Venturi-tube distributors both on the laboratory- and industrial-scale level, regarding the overall rate of reaction process achieved and/or catalyst load requirements.