Documents disponibles écrits par cet auteur

Catalyst deactivation in 3D CFD resolved particle simulations of propane dehydrogenation / Mohsen Behnam in Industrial & engineering chemistry research, Vol. 49 N° 21 (Novembre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 21 (Novembre 2010) . - pp. 10641-10650 Titre : Catalyst deactivation in 3D CFD resolved particle simulations of propane dehydrogenation Type de document : texte imprimé Auteurs : Mohsen Behnam, Auteur ; Anthony G. Dixon, Auteur ; Michiel Nijemeisland, Auteur Année de publication : 2011 Article en page(s) : pp. 10641-10650 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Dehydrogenation  Computational  fluid  dynamics  Deactivation  Catalyst Résumé : Catalyst deactivation by carbon deposition has been investigated for the dehydrogenation of propane to propene on a Cr2O3/Al2O3 catalyst. Computational fluid dynamics was used to couple the 3D transport and reaction processes occurring inside the cylindrical pellet to the gas flow around the pellet. The pellet scale reaction and carbon laydown are shown to be strongly affected by the bed scale tube wall heat flux supplied for the endothermic reactions, and the species distributions on the pellet surface are also affected by the case of reactant access to the particle. The development of particle internal gradients and carbon accumulation are illustrated for the early stages of deactivation. Carbon deposition is initially strongest in the high temperature regions close to the tube wall. As time progresses, the increased deactivation caused by the carbon acts to reduce all rates of reaction, and propene production and coke formation shift to other regions of the pellet. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=23447957 [article] Catalyst deactivation in 3D CFD resolved particle simulations of propane dehydrogenation [texte imprimé] / Mohsen Behnam, Auteur ; Anthony G. Dixon, Auteur ; Michiel Nijemeisland, Auteur . - 2011 . - pp. 10641-10650. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 21 (Novembre 2010) . - pp. 10641-10650 Mots-clés : Dehydrogenation  Computational  fluid  dynamics  Deactivation  Catalyst Résumé : Catalyst deactivation by carbon deposition has been investigated for the dehydrogenation of propane to propene on a Cr2O3/Al2O3 catalyst. Computational fluid dynamics was used to couple the 3D transport and reaction processes occurring inside the cylindrical pellet to the gas flow around the pellet. The pellet scale reaction and carbon laydown are shown to be strongly affected by the bed scale tube wall heat flux supplied for the endothermic reactions, and the species distributions on the pellet surface are also affected by the case of reactant access to the particle. The development of particle internal gradients and carbon accumulation are illustrated for the early stages of deactivation. Carbon deposition is initially strongest in the high temperature regions close to the tube wall. As time progresses, the increased deactivation caused by the carbon acts to reduce all rates of reaction, and propene production and coke formation shift to other regions of the pellet. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=23447957

CFD method to couple three - dimensional transport and reaction inside catalyst particles to the fixed bed flow field / Anthony G. Dixon in Industrial & engineering chemistry research, Vol. 49 N° 19 (Octobre 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 19 (Octobre 2010) . - pp. 9012–9025 Titre : CFD method to couple three - dimensional transport and reaction inside catalyst particles to the fixed bed flow field Type de document : texte imprimé Auteurs : Anthony G. Dixon, Auteur ; M. Ertan Taskin, Auteur ; Michiel Nijemeisland, Auteur Année de publication : 2010 Article en page(s) : pp. 9012–9025 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Computational  fluid  dynamics  Catalyst  particles  Flow  field Résumé : A new method is presented to couple the fluid flow in a fixed bed to the transport and reaction inside a catalyst particle, using computational fluid dynamics (CFD). The particle is modeled as solid, allowing no-slip surface flow boundary conditions to be used. Species transport inside the particle is represented by user-defined scalars, and the catalytic reactions are represented by user-defined functions. The new method is validated using standard cases for which exact results are known. Previous work has used a porous representation of the catalyst particle, which results in inaccurate temperature and species profiles due to an artifact of convective flux across the particle−fluid interface. This also gives incorrect values of the particle-to-fluid heat transfer coefficient, compared to standard correlations. Simulation results are presented for methane steam reforming using spherical particles in a wall segment, under tube inlet and midtube conditions, to illustrate the solid particle method. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100298q [article] CFD method to couple three - dimensional transport and reaction inside catalyst particles to the fixed bed flow field [texte imprimé] / Anthony G. Dixon, Auteur ; M. Ertan Taskin, Auteur ; Michiel Nijemeisland, Auteur . - 2010 . - pp. 9012–9025. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 19 (Octobre 2010) . - pp. 9012–9025 Mots-clés : Computational  fluid  dynamics  Catalyst  particles  Flow  field Résumé : A new method is presented to couple the fluid flow in a fixed bed to the transport and reaction inside a catalyst particle, using computational fluid dynamics (CFD). The particle is modeled as solid, allowing no-slip surface flow boundary conditions to be used. Species transport inside the particle is represented by user-defined scalars, and the catalytic reactions are represented by user-defined functions. The new method is validated using standard cases for which exact results are known. Previous work has used a porous representation of the catalyst particle, which results in inaccurate temperature and species profiles due to an artifact of convective flux across the particle−fluid interface. This also gives incorrect values of the particle-to-fluid heat transfer coefficient, compared to standard correlations. Simulation results are presented for methane steam reforming using spherical particles in a wall segment, under tube inlet and midtube conditions, to illustrate the solid particle method. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100298q