Documents disponibles écrits par cet auteur

Model building methodology for multiphase reaction systems / Rameshwar Hiwale in Industrial & engineering chemistry research, Vol. 50 N° 17 (Septembre 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 17 (Septembre 2011) . - pp. 10148-10157 Titre : Model building methodology for multiphase reaction systems Type de document : texte imprimé Auteurs : Rameshwar Hiwale, Auteur ; Sungwon Hwang, Auteur ; Robin Smith, Auteur Année de publication : 2011 Article en page(s) : pp. 10148-10157 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Modeling Résumé : A new approach to reactor model building for two-phase absorption processes is developed by considering simultaneously mass and heat transfer phenomena, and chemical reaction mechanism and kinetics. In particular, the interaction of mass and heat transfer with chemical reaction over the reactor design is considered to improve the accuracy of the simulation results. A novel methodology is applied to identify suitable reaction mechanisms and kinetics based on limited experimental data. This methodology allows the engineer to develop feasible reaction mechanisms in a systematic approach. Importantly, the required scope for any further lab experiments is identified, especially when the modeling needs further clarification for the reaction kinetics or mechanisms. In this way, a more robust reactor design can be achieved by making full use of experimental information, saving unnecessary laboratory and pilot plant experiments. For a case study, chlorine absorption to oleic acid is applied to the modeling of a laminar jet absorber. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24483658 [article] Model building methodology for multiphase reaction systems [texte imprimé] / Rameshwar Hiwale, Auteur ; Sungwon Hwang, Auteur ; Robin Smith, Auteur . - 2011 . - pp. 10148-10157. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 17 (Septembre 2011) . - pp. 10148-10157 Mots-clés : Modeling Résumé : A new approach to reactor model building for two-phase absorption processes is developed by considering simultaneously mass and heat transfer phenomena, and chemical reaction mechanism and kinetics. In particular, the interaction of mass and heat transfer with chemical reaction over the reactor design is considered to improve the accuracy of the simulation results. A novel methodology is applied to identify suitable reaction mechanisms and kinetics based on limited experimental data. This methodology allows the engineer to develop feasible reaction mechanisms in a systematic approach. Importantly, the required scope for any further lab experiments is identified, especially when the modeling needs further clarification for the reaction kinetics or mechanisms. In this way, a more robust reactor design can be achieved by making full use of experimental information, saving unnecessary laboratory and pilot plant experiments. For a case study, chlorine absorption to oleic acid is applied to the modeling of a laminar jet absorber. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24483658

Model building methodology for multiphase reaction systems — modeling of CO2 absorption in monoethanolamine for laminar jet absorbers and packing beds / Rameshwar Hiwale in Industrial & engineering chemistry research, Vol. 51 N° 11 (Mars 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 11 (Mars 2012) . - pp. 4328–4346 Titre : Model building methodology for multiphase reaction systems — modeling of CO2 absorption in monoethanolamine for laminar jet absorbers and packing beds Type de document : texte imprimé Auteurs : Rameshwar Hiwale, Auteur ; Sungwon Hwang, Auteur ; Robin Smith, Auteur Année de publication : 2012 Article en page(s) : pp. 4328–4346 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Chemical  reactions  Absorption  processes Résumé : This research has focused on a new methodology to develop a rigorous reactor model for gas–liquid chemical reactions in absorption processes. This involves simultaneous chemical reaction and mass transfer between two phases. In particular, all feasible chemical reaction mechanisms and kinetics are considered for the modeling to improve the accuracy of the simulation results. Detailed mathematical modeling is developed to identify physical properties of the key components. For a reactor design, a packed bed reactor has been developed with two different types of modeling approaches. The results of two separate models are compared with the laboratory experimental data. For a case study, CO2 absorption to monoethanolamine (MEA) solution is used based on a wide range of experimental data from both laminar jet absorber and packed bed column. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201869w [article] Model building methodology for multiphase reaction systems — modeling of CO2 absorption in monoethanolamine for laminar jet absorbers and packing beds [texte imprimé] / Rameshwar Hiwale, Auteur ; Sungwon Hwang, Auteur ; Robin Smith, Auteur . - 2012 . - pp. 4328–4346. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 11 (Mars 2012) . - pp. 4328–4346 Mots-clés : Chemical  reactions  Absorption  processes Résumé : This research has focused on a new methodology to develop a rigorous reactor model for gas–liquid chemical reactions in absorption processes. This involves simultaneous chemical reaction and mass transfer between two phases. In particular, all feasible chemical reaction mechanisms and kinetics are considered for the modeling to improve the accuracy of the simulation results. Detailed mathematical modeling is developed to identify physical properties of the key components. For a reactor design, a packed bed reactor has been developed with two different types of modeling approaches. The results of two separate models are compared with the laboratory experimental data. For a case study, CO2 absorption to monoethanolamine (MEA) solution is used based on a wide range of experimental data from both laminar jet absorber and packed bed column. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201869w

Operational optimization of batch distillation systems / Santosh Jain in Industrial & engineering chemistry research, Vol. 51 N° 16 (Avril 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 16 (Avril 2012) . - pp. 5749–5761 Titre : Operational optimization of batch distillation systems Type de document : texte imprimé Auteurs : Santosh Jain, Auteur ; Jin-Kuk Kim, Auteur ; Robin Smith, Auteur Année de publication : 2012 Article en page(s) : pp. 5749–5761 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Batch  distillation  systems Résumé : The optimal operation of batch distillation systems has been studied in this paper. A new approach termed the limiting gradient approach is introduced for effectively identifying feasible and cost-effective operating profiles for batch distillation systems. A new semirigorous model for batch distillation has been presented for considering holdup of the column, which is applicable for different batch distillation configurations. A novel optimization model incorporating the limiting gradient approach has been proposed, which significantly reduces computational burden to search for a feasible operation of a batch distillation column by considerably reducing effort for carrying out a large number of dynamic simulations required for optimization. Case studies have been presented to demonstrate the applicability of the approach for various batch distillation configurations and to illustrate how the proposed optimization framework systematically addresses different performance indices and objectives. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201844g [article] Operational optimization of batch distillation systems [texte imprimé] / Santosh Jain, Auteur ; Jin-Kuk Kim, Auteur ; Robin Smith, Auteur . - 2012 . - pp. 5749–5761. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 16 (Avril 2012) . - pp. 5749–5761 Mots-clés : Batch  distillation  systems Résumé : The optimal operation of batch distillation systems has been studied in this paper. A new approach termed the limiting gradient approach is introduced for effectively identifying feasible and cost-effective operating profiles for batch distillation systems. A new semirigorous model for batch distillation has been presented for considering holdup of the column, which is applicable for different batch distillation configurations. A novel optimization model incorporating the limiting gradient approach has been proposed, which significantly reduces computational burden to search for a feasible operation of a batch distillation column by considerably reducing effort for carrying out a large number of dynamic simulations required for optimization. Case studies have been presented to demonstrate the applicability of the approach for various batch distillation configurations and to illustrate how the proposed optimization framework systematically addresses different performance indices and objectives. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie201844g

Optimal design of mixed refrigerant cycles / Frank Del Nogal ; Jin-Kuk Kim ; Simon Perry ; Robin Smith in Industrial & engineering chemistry research, Vol. 47 n°22 (Novembre 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 n°22 (Novembre 2008) . - p. 8724–8740 Titre : Optimal design of mixed refrigerant cycles Type de document : texte imprimé Auteurs : Frank Del Nogal, Auteur ; Jin-Kuk Kim, Auteur ; Simon Perry, Auteur ; Robin Smith, Auteur Année de publication : 2008 Article en page(s) : p. 8724–8740 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : mixed  refrigerant  design Résumé : A new approach for the optimal design of mixed refrigerant cycles is presented. It is based on mathematical programming and offers significant improvements in relation to previous approaches. It includes multistage refrigerant compression, full enforcement of the minimum temperature difference in heat exchangers, simultaneous optimization of variables, consideration of capital costs, and the use of stochastic optimization (genetic algorithm) to overcome local optima. The approach can be applied to either single mixed refrigerant cycles or to systems consisting of two of these in cascade. The effectiveness of the method is illustrated by revisiting previously published liquified natural gas case studies, for which better and feasible solutions are produced, and which prove the importance of considering multistage compression and capital costs during optimization. The application of genetic algorithms in the design of mixed refrigerant cycles permits a greater confidence in the optimality of the results. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800515u [article] Optimal design of mixed refrigerant cycles [texte imprimé] / Frank Del Nogal, Auteur ; Jin-Kuk Kim, Auteur ; Simon Perry, Auteur ; Robin Smith, Auteur . - 2008 . - p. 8724–8740. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 n°22 (Novembre 2008) . - p. 8724–8740 Mots-clés : mixed  refrigerant  design Résumé : A new approach for the optimal design of mixed refrigerant cycles is presented. It is based on mathematical programming and offers significant improvements in relation to previous approaches. It includes multistage refrigerant compression, full enforcement of the minimum temperature difference in heat exchangers, simultaneous optimization of variables, consideration of capital costs, and the use of stochastic optimization (genetic algorithm) to overcome local optima. The approach can be applied to either single mixed refrigerant cycles or to systems consisting of two of these in cascade. The effectiveness of the method is illustrated by revisiting previously published liquified natural gas case studies, for which better and feasible solutions are produced, and which prove the importance of considering multistage compression and capital costs during optimization. The application of genetic algorithms in the design of mixed refrigerant cycles permits a greater confidence in the optimality of the results. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800515u

Optimization of productivity and thermodynamic performance of metabolic pathways / Mian Xu in Industrial & engineering chemistry research, Vol. 47 n°15 (Août 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 n°15 (Août 2008) . - p. 5669–5679 Titre : Optimization of productivity and thermodynamic performance of metabolic pathways Type de document : texte imprimé Auteurs : Mian Xu, Auteur ; Robin Smith, Auteur ; Jhuma Sadhukhan, Auteur Année de publication : 2008 Article en page(s) : p. 5669–5679 Note générale : Bibliogr. p. 5679 Langues : Anglais (eng) Mots-clés : Cellular  metabolic  systems;  Pathway  analysis;  Flux  balance  analysis;  Gibbs  free  energy Résumé : In this contribution, a novel optimization strategy has been presented that combines the metabolic flux analysis and pathway identification with the thermodynamic analysis of cellular metabolic systems. First, an optimal metabolic flux distribution among elementary pathways is identified by LP optimization subject to constraints on flux balance analysis, pathway analysis, and negative Gibbs free energy change for pathways, for achieving the maximum yield of products. The Gibbs free energy change for pathways is calculated from the new transformed Gibbs free energy of formation of external metabolites and cofactors that are in stoichiometric balance in metabolic pathways. The consideration of thermodynamic constraints on pathways ensures the selection of feasible pathways. Thereafter, the Gibbs free energy change of pathways is minimized to predict the optimal reaction conditions that facilitate such pathways. Thus, the optimization approach derives the optimal pathway distribution and conditions for the best performance of cellular systems. The effectiveness of the methodology is demonstrated by a case study on the optimization of pentose phosphate pathway (PPP) and the glycolysis cycle of the insilico Escherichia coli. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie070352f [article] Optimization of productivity and thermodynamic performance of metabolic pathways [texte imprimé] / Mian Xu, Auteur ; Robin Smith, Auteur ; Jhuma Sadhukhan, Auteur . - 2008 . - p. 5669–5679. Bibliogr. p. 5679 Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 n°15 (Août 2008) . - p. 5669–5679 Mots-clés : Cellular  metabolic  systems;  Pathway  analysis;  Flux  balance  analysis;  Gibbs  free  energy Résumé : In this contribution, a novel optimization strategy has been presented that combines the metabolic flux analysis and pathway identification with the thermodynamic analysis of cellular metabolic systems. First, an optimal metabolic flux distribution among elementary pathways is identified by LP optimization subject to constraints on flux balance analysis, pathway analysis, and negative Gibbs free energy change for pathways, for achieving the maximum yield of products. The Gibbs free energy change for pathways is calculated from the new transformed Gibbs free energy of formation of external metabolites and cofactors that are in stoichiometric balance in metabolic pathways. The consideration of thermodynamic constraints on pathways ensures the selection of feasible pathways. Thereafter, the Gibbs free energy change of pathways is minimized to predict the optimal reaction conditions that facilitate such pathways. Thus, the optimization approach derives the optimal pathway distribution and conditions for the best performance of cellular systems. The effectiveness of the methodology is demonstrated by a case study on the optimization of pentose phosphate pathway (PPP) and the glycolysis cycle of the insilico Escherichia coli. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie070352f