Chemical Engineering Science, Vol.100, 373-383, 2013
Simulation of structured catalytic packings in a bubble-point reactor
This work investigates structured catalytic packings in a bubble-point reactor in which the reaction and flash occur simultaneously. A three-dimensional (3D) computational fluid dynamics (CFD) model was used to determine the optimum operating conditions and to examine the reactor performance when traditional catalyst pellets were replaced with BeiHua (BH) structured catalytic packings for benzene alkylation with propylene. It was found that the optimum operating conditions were a reaction temperature of 160 degrees C and a molar ratio of benzene to propylene in the feed of 4.0. In this work, we also explored the relationship between the geometric configuration and the reactor performance. The momentum transfer (pressure drop), heat transfer (Nu number), mass transfer (Sh number), propylene conversion, cumene selectivity, and effectiveness factor were determined for different geometric configurations, which included changes in the corrugation angle, ratio of the packing height to the diameter, and ratio of the areas of the reaction to open-channel regions. Two new types of transition or wave-like structures (30-45-30 degrees and 45-30-45 degrees), which resulted in a higher propylene conversion, cumene selectivity, and effectiveness factor, were adopted. Furthermore, the applicability of this new technology for benzene alkylation with propylene was verified in a pilot plant. (C) 2013 Elsevier Ltd. All rights reserved.