A novel dynamic membrane reactor concept with radial-flow pattern for reacting material and axial-flow pattern for sweeping gas in catalytic naphtha reformers

Authors

  • Davood Iranshahi,

    1. School of Chemical and Petroleum Engineering, Dept. of Chemical Engineering, Shiraz University, Shiraz 71345, Iran
    Search for more papers by this author
  • Ehsan Pourazadi,

    1. School of Chemical and Petroleum Engineering, Dept. of Chemical Engineering, Shiraz University, Shiraz 71345, Iran
    Search for more papers by this author
  • Khadijeh Paymooni,

    1. School of Chemical and Petroleum Engineering, Dept. of Chemical Engineering, Shiraz University, Shiraz 71345, Iran
    Search for more papers by this author
  • Mohammad Reza Rahimpour

    Corresponding author
    1. School of Chemical and Petroleum Engineering, Dept. of Chemical Engineering, Shiraz University, Shiraz 71345, Iran
    • School of Chemical and Petroleum Engineering, Dept. of Chemical Engineering, Shiraz University, Shiraz 71345, Iran
    Search for more papers by this author

Abstract

Naphtha reforming units are of high interest for hydrogen production in refineries. In this regard, the application of membrane concept in radial-flow tubular naphtha reactors for hydrogen production is proposed. Because of the importance of the pressure drop problem in catalytic naphtha reforming units, the radial-flow reactors are proposed. A radial-flow tubular membrane reactor (RF-TMR) with the radial-flow pattern of the naphtha feed and the axial-flow pattern of the sweeping gas is proposed as an alternative configuration for conventional axial-flow tubular reactors (AF-TR). The cross-sectional area of the tubular reactor is divided into some subsections in which walls of the gaps between subsections are coated with the Pd-Ag membrane layer. A dynamic mathematical model considering radial and axial coordinates ((r, z)-coordinates) has been developed to investigate the performance of the new configuration. Results show ∼300 and 11 kg/h increase in aromatic and hydrogen production rates in RF-TMR compared with AF-TR, respectively. Furthermore, smaller catalyst particles with higher efficiency can be used in RF-TMR due to a slight pressure drop. The enhancement in aromatics (octane number) and hydrogen productions owing to applying simultaneously the membrane concept and radial-flow pattern in naphtha reactors motivates the application of RF-TMR in refineries. © 2011 American Institute of Chemical Engineers AIChE J, 2012

Ancillary