Documents disponibles écrits par cet auteur

Modeling temperature profiles of a catalytic autothermal methane reformer with nickel catalyst / Diego Scognamiglio in Industrial & engineering chemistry research, Vol. 48 N°4 (Février 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N°4 (Février 2009) . - pp. 1804–1815 Titre : Modeling temperature profiles of a catalytic autothermal methane reformer with nickel catalyst Type de document : texte imprimé Auteurs : Diego Scognamiglio, Auteur ; Lucia Russo, Auteur ; Pier Luca Maffettone, Auteur Année de publication : 2009 Article en page(s) : pp. 1804–1815 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : One-dimensional  heterogeneous  model  Autothermal  methane  Fixed-bed  reactor  Kinetic  modelSteam-to-methane  ratios Résumé : In this work, a one-dimensional heterogeneous model for the autothermal reforming of methane in a catalytic (Ni/Al2O3 catalyst) fixed-bed reactor is proposed. The kinetic model implements an indirect reaction scheme and includes a reduction factor that is dependent on the oxygen concentration. Such a factor delays the reforming and water-gas shift reactions, with respect to the oxidation reactions. Experiments at different steam-to-methane ratios and feed flow rates were conducted in a small-scale reactor to identify and validate the proposed mathematical model. To this end, temperature profiles in the solid phase were measured with an infrared camera. The agreement between experimental data and model predictions is very good for all the investigated operating conditions. In particular, the model predicts the strong separation between the oxidation and the experimentally observed reforming zones well. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800518e [article] Modeling temperature profiles of a catalytic autothermal methane reformer with nickel catalyst [texte imprimé] / Diego Scognamiglio, Auteur ; Lucia Russo, Auteur ; Pier Luca Maffettone, Auteur . - 2009 . - pp. 1804–1815. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N°4 (Février 2009) . - pp. 1804–1815 Mots-clés : One-dimensional  heterogeneous  model  Autothermal  methane  Fixed-bed  reactor  Kinetic  modelSteam-to-methane  ratios Résumé : In this work, a one-dimensional heterogeneous model for the autothermal reforming of methane in a catalytic (Ni/Al2O3 catalyst) fixed-bed reactor is proposed. The kinetic model implements an indirect reaction scheme and includes a reduction factor that is dependent on the oxygen concentration. Such a factor delays the reforming and water-gas shift reactions, with respect to the oxidation reactions. Experiments at different steam-to-methane ratios and feed flow rates were conducted in a small-scale reactor to identify and validate the proposed mathematical model. To this end, temperature profiles in the solid phase were measured with an infrared camera. The agreement between experimental data and model predictions is very good for all the investigated operating conditions. In particular, the model predicts the strong separation between the oxidation and the experimentally observed reforming zones well. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie800518e

Optimal Reference Trajectory Shaping and Robust Gain-Scheduling for Transition Control of Nonlinear Processes / Pietro Altimari in Industrial & engineering chemistry research, Vol. 48 N° 20 (Octobre 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 20 (Octobre 2009) . - pp. 9128–9140 Titre : Optimal Reference Trajectory Shaping and Robust Gain-Scheduling for Transition Control of Nonlinear Processes Type de document : texte imprimé Auteurs : Pietro Altimari, Auteur ; Lucia Russo, Auteur ; Erasmo Mancusi, Auteur Année de publication : 2010 Article en page(s) : pp. 9128–9140 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Nonlinear  processes  Transition  control  Gain  scheduling Résumé : A novel method for transition control of nonlinear processes is presented. Gain scheduling is implemented to ensure stability and desired output behavior over the operating region of interest while transition between the initial and the final steady state is achieved by predictive reference control (or reference governor). In this framework, the search of a feasible reference input sequence is performed so that the closed-loop system moves along an optimal curve of steady states. This curve is constructed off-line so that its points lie far from the border of the process constraint set and correspond to satisfactory controllability properties of the uncontrolled plant. Moreover, bifurcation analysis of the closed-loop system is performed by varying the reference signal according to the selected curve. In this way, regions of state multiplicity and/or instability are identified enabling the choice of the controller parameters values preventing transitions to undesired solution regimes. The method is validated on a simulated problem of start-up control of a jacketed continuous stirred tank reactor. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9001553 [article] Optimal Reference Trajectory Shaping and Robust Gain-Scheduling for Transition Control of Nonlinear Processes [texte imprimé] / Pietro Altimari, Auteur ; Lucia Russo, Auteur ; Erasmo Mancusi, Auteur . - 2010 . - pp. 9128–9140. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 20 (Octobre 2009) . - pp. 9128–9140 Mots-clés : Nonlinear  processes  Transition  control  Gain  scheduling Résumé : A novel method for transition control of nonlinear processes is presented. Gain scheduling is implemented to ensure stability and desired output behavior over the operating region of interest while transition between the initial and the final steady state is achieved by predictive reference control (or reference governor). In this framework, the search of a feasible reference input sequence is performed so that the closed-loop system moves along an optimal curve of steady states. This curve is constructed off-line so that its points lie far from the border of the process constraint set and correspond to satisfactory controllability properties of the uncontrolled plant. Moreover, bifurcation analysis of the closed-loop system is performed by varying the reference signal according to the selected curve. In this way, regions of state multiplicity and/or instability are identified enabling the choice of the controller parameters values preventing transitions to undesired solution regimes. The method is validated on a simulated problem of start-up control of a jacketed continuous stirred tank reactor. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie9001553