WITHDRAWN: Mechanism of process intensification by microchannel reactors

Abstract

The unique advantages of microchannel reactors are enhanced heat transfer due to the large surface area-to-volume ratio, and enhanced mass transfer. The good heat transfer properties allow a precise temperature control of reactions. However, the mechanisms for the effects of design factors on heat transfer characteristics are still not fully understood. This study relates to a thermochemical process for producing hydrogen by the catalytic endothermic reaction of methanol with steam in a thermally integrated microchannel reforming reactor. Computational fluid dynamics simulations are conducted to better understand the consumption, generation, and exchange of thermal energy between endothermic and exothermic processes in the reactor. The effects of wall heat conduction properties on heat transfer characteristics and reactor performance are investigated. The results indicate that the yields and selectivity can be improved by using microchannel process technology at more extreme parameters. Process intensification may be achieved using microchannel process technology where chemical processors are employed that are characterized by parallel arrays of microchannels. Processes are intensified using microchannel process technology by decreasing transfer resistance between process fluids and channel walls. Process intensification allows for use of more active catalysts than conventional processes, greatly increasing the throughput per unit volume. As a result of process intensification, overall system volumes can be reduced by about ten to one hundred-fold or more when compared to conventional hardware.