A numerical comparison of alternative three-phase reactors with a conventional trickle-bed reactor. The advantages of countercurrent flow for hydrodesulfurization

A computer model was developed to compare a conventional cocurrent trickle- bed reactor with two novel countercurrent three-phase reactors: the three-l evels-of-porosity reactor and the internally finned monolith reactor. The h ydrodesulfurization of a vacuum gas oil was taken as a case study. It was f ound that the application of countercurrent flow in the novel reactors resu lts in significant increase of conversion. Sensitivity for mass transfer an d H2S inhibition were investigated. Reduced mass transfer compared to a con ventional trickle-bed does not limit the reaction. (C) 1999 Elsevier Scienc e Ltd. All rights reserved.