Documents disponibles écrits par cet auteur

Dynamic simulation of continuous-contact separation processes with the moment transformation method / Jonas Roininen in Industrial & engineering chemistry research, Vol. 49 N° 7 (Avril 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 7 (Avril 2010) . - pp. 3365–3373 Titre : Dynamic simulation of continuous-contact separation processes with the moment transformation method Type de document : texte imprimé Auteurs : Jonas Roininen, Auteur ; Ville Alopaeus, Auteur Année de publication : 2010 Article en page(s) : pp. 3365–3373 Note générale : Idustrial Chemistry Langues : Anglais (eng) Mots-clés : Dynamic  Simulation  Separation  Moment  Transformation  Contact Résumé : A model for the simulation of continuous-contact separation processes, based on heat and energy balances, multicomponent mass transfer, and chemical engineering correlations for mass and heat transfer coefficients and liquid holdup is developed and solved with the moment transformation method. Polynomials are used to approximate the concentration and flow rate profiles within the packing. The moment transformation method is used to transform the partial differential equations into a system of differential-algebraic equations that is solved with Newton’s method. The model can be used for both steady-state and dynamic simulation, and it can also be used for systems with axial dispersion. The features of the model are demonstrated with an example of ternary distillation. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901572a [article] Dynamic simulation of continuous-contact separation processes with the moment transformation method [texte imprimé] / Jonas Roininen, Auteur ; Ville Alopaeus, Auteur . - 2010 . - pp. 3365–3373. Idustrial Chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 7 (Avril 2010) . - pp. 3365–3373 Mots-clés : Dynamic  Simulation  Separation  Moment  Transformation  Contact Résumé : A model for the simulation of continuous-contact separation processes, based on heat and energy balances, multicomponent mass transfer, and chemical engineering correlations for mass and heat transfer coefficients and liquid holdup is developed and solved with the moment transformation method. Polynomials are used to approximate the concentration and flow rate profiles within the packing. The moment transformation method is used to transform the partial differential equations into a system of differential-algebraic equations that is solved with Newton’s method. The model can be used for both steady-state and dynamic simulation, and it can also be used for systems with axial dispersion. The features of the model are demonstrated with an example of ternary distillation. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie901572a

Improved hydrodynamic model for wetting Efficiency, pressure drop, and liquid hjoldup in trickle-bed reactors / Katja Lappalainen in Industrial & engineering chemistry research, Vol. 47 n°21 (Novembre 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 n°21 (Novembre 2008) . - p. 8436–8444 Titre : Improved hydrodynamic model for wetting Efficiency, pressure drop, and liquid hjoldup in trickle-bed reactors Type de document : texte imprimé Auteurs : Katja Lappalainen, Auteur ; Ville Alopaeus, Auteur ; Mikko Manninen, Auteur Année de publication : 2008 Article en page(s) : p. 8436–8444 Note générale : Chemical engineeing Langues : Anglais (eng) Mots-clés : Improved  hydrodynamic Résumé : An improved hydrodynamic model is developed for estimating wetting efficiency, pressure drop, and liquid holdup in trickle-bed reactors. The model is based on the hydrodynamic model presented in Alopaeus et al. [Alopaeus, V.; Hynynen, K.; Aittamaa, J.; Manninen, M. Modeling of Gas−Liquid Packed-Bed Reactor with Momentum Equations and Local Interactions Closures. Ind. Eng. Chem. Res. 2006, 45, 8189.], which is extended to take into account partial wetting of the packing. In addition, the applicability of the 1D model for three-dimensional situations is considered in the process of model development. The wetting efficiency model is formulated on the basis of dimensional analysis and carrying out systematic tests with varying combinations of dimensionless groups. In addition, the wetting efficiency model is not evaluated solely on the wetting efficiency data, but also it is tested systematically with the hydrodynamic model. Furthermore the consistency of the model characteristics to common experimental observations is discussed. Finally, the model’s ability to predict wetting efficiency, dimensionless pressure drop, and liquid saturation was compared to other existing models and improvements were found in all areas. The resulting hydrodynamic model can be used equally as a tool for design and modeling of large scale industrial reactors as well as a tool for complicated three-dimensional simulations. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8003754 [article] Improved hydrodynamic model for wetting Efficiency, pressure drop, and liquid hjoldup in trickle-bed reactors [texte imprimé] / Katja Lappalainen, Auteur ; Ville Alopaeus, Auteur ; Mikko Manninen, Auteur . - 2008 . - p. 8436–8444. Chemical engineeing Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 n°21 (Novembre 2008) . - p. 8436–8444 Mots-clés : Improved  hydrodynamic Résumé : An improved hydrodynamic model is developed for estimating wetting efficiency, pressure drop, and liquid holdup in trickle-bed reactors. The model is based on the hydrodynamic model presented in Alopaeus et al. [Alopaeus, V.; Hynynen, K.; Aittamaa, J.; Manninen, M. Modeling of Gas−Liquid Packed-Bed Reactor with Momentum Equations and Local Interactions Closures. Ind. Eng. Chem. Res. 2006, 45, 8189.], which is extended to take into account partial wetting of the packing. In addition, the applicability of the 1D model for three-dimensional situations is considered in the process of model development. The wetting efficiency model is formulated on the basis of dimensional analysis and carrying out systematic tests with varying combinations of dimensionless groups. In addition, the wetting efficiency model is not evaluated solely on the wetting efficiency data, but also it is tested systematically with the hydrodynamic model. Furthermore the consistency of the model characteristics to common experimental observations is discussed. Finally, the model’s ability to predict wetting efficiency, dimensionless pressure drop, and liquid saturation was compared to other existing models and improvements were found in all areas. The resulting hydrodynamic model can be used equally as a tool for design and modeling of large scale industrial reactors as well as a tool for complicated three-dimensional simulations. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8003754

Modeling and simulation of an industrial trickle-bed reactor for benzene hydrogenation / Jonas Roininen 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. 1866–1872 Titre : Modeling and simulation of an industrial trickle-bed reactor for benzene hydrogenation : model validation against plant data Type de document : texte imprimé Auteurs : Jonas Roininen, Auteur ; Ville Alopaeus, Auteur ; Sami Toppinen, Auteur Année de publication : 2009 Article en page(s) : pp. 1866–1872 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Trickle-bed  reactor  Gas-liquid  mass  transfer  Hydrogen  Heterogeneous  three-phase  reactor  model Résumé : A heterogeneous three-phase reactor model is used to simulate an industrial trickle-bed reactor for benzene hydrogenation, and simulated temperature profiles are compared to actual plant data. The agreement of model predictions with measured data is excellent. Analysis of the results shows that the process is limited by gas−liquid mass transfer of hydrogen. The simulation results show high sensitivity toward the liquid film mass transfer coefficient kLa. Some correlations for kLa are tested, and their validity is evaluated. The estimated values of kLa and kGa are comparable to measured values from a bench-scale reactor reported in the literature. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801411n [article] Modeling and simulation of an industrial trickle-bed reactor for benzene hydrogenation : model validation against plant data [texte imprimé] / Jonas Roininen, Auteur ; Ville Alopaeus, Auteur ; Sami Toppinen, Auteur . - 2009 . - pp. 1866–1872. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N°4 (Février 2009) . - pp. 1866–1872 Mots-clés : Trickle-bed  reactor  Gas-liquid  mass  transfer  Hydrogen  Heterogeneous  three-phase  reactor  model Résumé : A heterogeneous three-phase reactor model is used to simulate an industrial trickle-bed reactor for benzene hydrogenation, and simulated temperature profiles are compared to actual plant data. The agreement of model predictions with measured data is excellent. Analysis of the results shows that the process is limited by gas−liquid mass transfer of hydrogen. The simulation results show high sensitivity toward the liquid film mass transfer coefficient kLa. Some correlations for kLa are tested, and their validity is evaluated. The estimated values of kLa and kGa are comparable to measured values from a bench-scale reactor reported in the literature. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie801411n

Modeling of Catalyst Activity Profiles in Fixed-Bed Reactors with a Moment Transformation Method / Jonas Roininen in Industrial & engineering chemistry research, Vol. 47 n°21 (Novembre 2008) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 47 n°21 (Novembre 2008) . - p 8192–8196 Titre : Modeling of Catalyst Activity Profiles in Fixed-Bed Reactors with a Moment Transformation Method Type de document : texte imprimé Auteurs : Jonas Roininen, Auteur ; Ville Alopaeus, Auteur Année de publication : 2008 Article en page(s) : p 8192–8196 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : catalyst  activity  profiles Résumé : A model for pseudo-steady-state catalyst activity profiles in a fixed-bed reactor is presented. It is based on conservation of moments of the exact catalyst activity profile, as calculated from the catalyst deactivation rate. These moments are then transformed analytically into a polynomial approximation of the activity profile for each time step. Then temporal and spatial evolution of the catalyst activity can be followed, and correspondingly accurate predictions of reactor performance with partly deactivated catalyst can be carried out. The present model is especially suitable for situations where the observed reaction rate is not solely determined by kinetics of a catalytic reaction, but also by heat or mass transfer limitations, or if the pressure drop in the reactor affects reaction rates. A further important class is when multiple reactions are taking place with different mechanisms so that the dominant mechanism changes as catalyst is deactivated. It can also be used in catalyst lifespan design, since measured temperature gradients can be followed by the model and transformed into information regarding catalyst activity profile. Also optimization of reactor operation with partly deactivated catalyst can be improved. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8007665 [article] Modeling of Catalyst Activity Profiles in Fixed-Bed Reactors with a Moment Transformation Method [texte imprimé] / Jonas Roininen, Auteur ; Ville Alopaeus, Auteur . - 2008 . - p 8192–8196. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 47 n°21 (Novembre 2008) . - p 8192–8196 Mots-clés : catalyst  activity  profiles Résumé : A model for pseudo-steady-state catalyst activity profiles in a fixed-bed reactor is presented. It is based on conservation of moments of the exact catalyst activity profile, as calculated from the catalyst deactivation rate. These moments are then transformed analytically into a polynomial approximation of the activity profile for each time step. Then temporal and spatial evolution of the catalyst activity can be followed, and correspondingly accurate predictions of reactor performance with partly deactivated catalyst can be carried out. The present model is especially suitable for situations where the observed reaction rate is not solely determined by kinetics of a catalytic reaction, but also by heat or mass transfer limitations, or if the pressure drop in the reactor affects reaction rates. A further important class is when multiple reactions are taking place with different mechanisms so that the dominant mechanism changes as catalyst is deactivated. It can also be used in catalyst lifespan design, since measured temperature gradients can be followed by the model and transformed into information regarding catalyst activity profile. Also optimization of reactor operation with partly deactivated catalyst can be improved. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie8007665