Suiting Dynamic Models of Fixed-Bed Catalytic Reactors for Computer-Based Applications

Eduardo Coselli Vasco de Toledo, Edvaldo Rodrigo Morais, Delba Nisi Cosme Melo, Adriano Pinto Mariano, João F. C. A. Meyer, Rubens Maciel Filho

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Petrobras, Paulínia Refinery (REPLAN). Rodovia SP 332 - Km 132, P.O. Box 1, 13140-000, Paulínia-SP, Brazil.

DOI: 10.4236/eng.2011.37094                

Abstract

This work investigated the applicability of heterogeneous and pseudo-homogeneous models to predict the dynamic behavior of a fixed-bed catalytic reactor. Some issues concerning the dynamic behavior of the system were discussed, such as the prediction of the inverse response phenomenon. The proposed models (Het- erogeneous I and II and Pseudo-homogeneous) were able to predict with qualitative similarity the main characteristics of the dynamic behavior of a fixed-bed catalytic reactor, including the inverse response. The computational time demanded for the solution of the heterogeneous models was 10 to 50% longer than in the case of the pseudo-homogeneous model, making the use of the former suitable for applications where computational time is not the major restriction (off-line applications). On the other hand, when on-line applications are required, the simplified model (Pseudo-homogeneous model) showed to be a good alternative because this model was able to predict (qualitatively) the dynamics of the reactor using a faster and easier numerical solution.

Keywords

Dynamic Models, Inverse Response, Fixed-Bed, Catalytic Reactors, Simulation

Conflicts of Interest

The authors declare no conflicts of interest.

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