A Double-Slit Model Developed Can Predict the Frictional Two-Phase Pressure Drop, External Liquid Holdup, Pellet-Scale External Wetting Efficiency, and Gas - Liquid Interfacial Area in Cocurrent Downflow Trickle-Bed Reactors Operated under Partially Wetted Conditions in the Trickle Flow Regime. the Model, an Extension of the Holub Et Al. (1992, 1993) Mechanistic Pore-Scale Phenomenological Approach, Was Designed to Mimic the Actual Bed Void by Two Inclined and Interconnected Slits: Wet and Dry Slit. the External Wetting Efficiency is Linked to Both the Pressure Drop and External Liquid Holdup. the Model Also Predicts Gas - Liquid Interfacial Areas in Partially Wetted Conditions. an Extensive Trickle-Flow Regime Database Including over 1,200 Measurements of Two-Phase Pressure Drop, Liquid Holdup, Gas - Liquid Interfacial Area and Wetting Efficiency, Published in 1974-1998 on the Partial-Wetted Conditions, Was Used to Validate the Modeling Approach. Two New Improved Slip-Factor Functions Were Also Developed using Dimensional Analysis and Artificial Neural Networks. High-Pressure and -Temperature Wetting Efficiency, Liquid Holdup, Pressure Drop, and Gas - Liquid Interfacial Area Data from the Literature on the Trickle-Flow Regime using Conventional Monosized Beds and Catalyst Bed-Dilution Conditions Were Successfully Forecasted by the Model.


Chemical and Biochemical Engineering

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Article - Journal

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Publication Date

01 Jan 2000