Chemical Engineering and Processing, Vol.52, 63-73, 2012
A comparative study of two different configurations for exothermic-endothermic heat exchanger reactor
The coupling of the energy intensive endothermic reaction systems with appropriate exothermic reactions reduces the size of the reactors and can improve the thermal efficiency of processes. One type of a suitable reactor for such a kind of coupling is the heat exchanger reactor. In this study, the catalytic methanol synthesis is coupled with the catalytic dehydrogenation of cyclohexane to benzene in an integrated reactor formed from two fixed beds separated by a wall where heat is transferred across the surface of the tube. A steady-state heterogeneous model of the two fixed beds predicts the performance of the two different configurations of the thermally coupled reactor. The co-current mode is investigated and the simulation results are compared with the corresponding predictions for the industrial methanol fixed bed reactor operating in the same feed conditions. The results of the study reveal that should the exothermic and endothermic reactions be located in the shell side and tube side, respectively, the methanol production rate will increase in comparison with the conventional methanol synthesis reactor as well as the case where the exothermic reaction is located in the tube side and endothermic reaction in the shell side. (C) 2011 Elsevier B.V. All rights reserved.
Keywords:Methanol production;Cyclohexane dehydrogenation;Two different configurations;Thermally coupled reactor