Pressure Drop and Liquid Holdup in Trickle Flow Reactors:  Improved Ergun Constants and Slip Correlations for the Slit Model

Abstract

The original and extended Holub phenomenological models for pressure drop and liquid holdup in trickle flow regime systematically under-predicted frictional pressure drops at elevated pressure and at high gas throughputs. On the basis of an extensive historic trickle flow regime database and Ergun bed constants (over 4000 measurements from 34 references between 1959 and 1998), state-of-the-art correlations for shear and velocity slip factors and Ergun single-phase flow bed constants (Blake−Kozeny−Carman and Burke−Plummer bed parameters) were developed. The correlations involved combination of feed-forward neural networks and dimensional analysis. The shear and velocity slip factors were expressed as a function of the six most expressive dimensionless groups (Re L, Re G, Fr L, We L, X L, St L), whereas Blake−Kozeny−Carman and Burke−Plummer bed parameters were correlated to particle equivalent diameter, sphericity factor, bed porosity, and column diameter. These correlations fed into Holub's phenomenological model improved noticeably the prediction of frictional pressure drop and liquid holdup in trickle flow reactors.

Carbon materials and catalytic wet air oxidation of organic pollutants in wastewater

“…This situation was expected from the calculated low external [230] and static [231] liquid hold up taking values between 0.06 and 0.1. Partial catalyst wetting varying with the liquid flow rate used transforms the kinetic study into a delicate task.…”

Applications of tomography in bubble column and trickle bed reactors

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Stretching operational life of trickle‐bed filters by liquid‐induced pulse flow

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