A 38-lumped kinetic model for reforming reaction and its application in continuous catalytic reforming

Based on the lumping theory and catalytic reforming reaction mechanisms,a new kinetic model involving 38 lumped components and 86 reactions was developed for the industrial continuous catalytic reforming(CCR).In the proposed model the reactants were lumped into C6—C11+ according to the number of carbon atoms,the components with the same carbon atoms number were divided into normal-paraffin,iso-paraffin,5-cyclanes,6-cyclanes and aromatics respectively,and the cracking products were lumped into C1—C5 lumps.The reaction network of the model was on the basis of the reaction mechanism of bi-functional catalyst and related kinetic theory.As the detailed division of the lumped components,most of the reactants information could be covered,consequently the model could be more realistic.By making reasonable simplification,86 model parameters were identified and estimated using the hierarchical strategy and BFGS algorithm from literature data.The model developed was used for simulation of a refinery reformer to validate the effectiveness.The prediction error of each component in the outlet products of the last reactor was within 0.7%,and that of temperature drop for each reactor was below 5℃.So,the reliability and accuracy of the model could meet the requirements of industrial applications.The model was then applied to predict the aromatics yield,and the average prediction error was only 0.42%.The result showed that the trend and precision of the aromatics yield prediction were satisfied in a long period of time.Finally,the process optimization was implemented based on the proposed model,and an increase of 0.17% on aromatics yield was obtained by a slight tuning of each inlet temperature.The optimization result could provide a guideline for the optimization of the CCR unit.