On the use of approximate velocity profiles for modeling multiphase reactors

Authors

  • William H. Zimmerman,

    1. Kinetics, Catalysis, and Reaction Engineering Laboratory, Department of Chemical Engineering, Texas A&M University, College Station, TX 77843
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  • Dragomir B. Bukur

    Corresponding author
    1. Kinetics, Catalysis, and Reaction Engineering Laboratory, Department of Chemical Engineering, Texas A&M University, College Station, TX 77843
    • Kinetics, Catalysis, and Reaction Engineering Laboratory, Department of Chemical Engineering, Texas A&M University, College Station, TX 77843
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Abstract

The use of an approximate axial gas velocity profile in a two-phase reactor model has been studied. The approximate velocity was assumed to vary linearly with conversion, which reduces the number of differential equations to be solved. The approximate model was studied in systems with one or two reactions. In most cases, the approximate and rigorous solutions were in good agreement. However, when mass transfer strongly influenced the velocity profile, errors in conversion became significant (∼ 15%). Reactions with no change in the number of moles are also subject to errors if the rigorous velocity profile is not accounted for.

Abstract

On a étudié l'utilisation d'un profil de vitesse axiale du gaz approximative dans un modèle a reacteur biphasique. On a supposé que la vitesse approximative variait de façon linéaire avec la conversion, ce qui réduit le nombre d'équations différentielles à résoudre. Le modèle approximatif a été étudié dans les systèmes avec une ou deux réactions. Dans la plupart des cas, les solutions approximatives et rigoureuses montraient un bon accord. Cependant, lorsque le transfert de matière influence fortement le profil de vitesse, les erreurs dans la conversion deviennent significatives ( ∼ 15%). Les réactions n'entraînant aucun changement dans le nombre de moles sont également susceptibles d'erreurs si on ne tient pas compte rigoureusement du profil de vitesse.

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