Modeling of trickle-bed reactors with exothermic reactions using cell network approach

Abstract

One-dimensional (1D) and two-dimensional (2D) cell network models were developed to simulate the steady-state behavior of trickle-bed reactors employed for the highly exothermic hydrotreating of benzene. The multiphase mass transfer-reaction model and novel solution method are discussed in this report. The 1D model was shown to satisfactorily simulate the axial temperature field observed experimentally for multiphase flow with exothermic reactions. The 2D reactor modeling provided valuable information about local hot spot behavior within the multiphase reactor, identifying situations in which hot spots may form. The model took into consideration the heterogeneous nature of liquid distribution, including radial liquid maldistribution and partial external wetting. This approach was proven to be stable and efficient in dealing with the complex interaction of phase vaporization and temperature rise. Through analysis and discussion, this report established the cell network model as a valid representation of the flow environment produced in a trickle bed with exothermic reactions.