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Integration of nonlinear crude distillation unit models in refinery planning optimization / Abdulrahman M. Alattas in Industrial & engineering chemistry research, Vol. 50 N° 11 (Juin 2011) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 50 N° 11 (Juin 2011) . - pp. 6860-6870 Titre : Integration of nonlinear crude distillation unit models in refinery planning optimization Type de document : texte imprimé Auteurs : Abdulrahman M. Alattas, Auteur ; Ignacio E. Grossmann, Auteur ; Ignasi Palou-Rivera, Auteur Année de publication : 2011 Article en page(s) : pp. 6860-6870 Note générale : Chimie industrielle Langues : Anglais (eng) Mots-clés : Optimization  Planning  Refinery  Modeling  Distillation Résumé : Production planning modeling is an essential tool in the operation and management of modern refineries. It has traditionally relied on linear programming (LP) principles and methods for simple and robust planning models, such as the fixed-yield planning models and swing cuts planning models. However, these models fail to reflect the true nonlinear nature of the processing units. In this work, the fractionation index model (FI) is developed to add nonlinearity to the linear refinery planning models. The FI model is developed as a more accurate nonlinear model for the complex crude distillation unit (CDU) than the fixed yield or the swing cuts models. The resulting simple model optimizes the crude cuts quantities and temperature. It has the benefits of being crude independent, characteristics of the CDU, and readily calculated. An example of the FI CDU model is presented. The FI-based refinery planning model is then developed and tested with a refinery planning example. The results are compared to the common fixed yield and swing cuts models. The FI refinery planning model predicted higher profit based on different crude purchase decision. Despite an order of magnitude increase in the problem size, the FI planning model did not require significantly longer solution times. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24199903 [article] Integration of nonlinear crude distillation unit models in refinery planning optimization [texte imprimé] / Abdulrahman M. Alattas, Auteur ; Ignacio E. Grossmann, Auteur ; Ignasi Palou-Rivera, Auteur . - 2011 . - pp. 6860-6870. Chimie industrielle Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 50 N° 11 (Juin 2011) . - pp. 6860-6870 Mots-clés : Optimization  Planning  Refinery  Modeling  Distillation Résumé : Production planning modeling is an essential tool in the operation and management of modern refineries. It has traditionally relied on linear programming (LP) principles and methods for simple and robust planning models, such as the fixed-yield planning models and swing cuts planning models. However, these models fail to reflect the true nonlinear nature of the processing units. In this work, the fractionation index model (FI) is developed to add nonlinearity to the linear refinery planning models. The FI model is developed as a more accurate nonlinear model for the complex crude distillation unit (CDU) than the fixed yield or the swing cuts models. The resulting simple model optimizes the crude cuts quantities and temperature. It has the benefits of being crude independent, characteristics of the CDU, and readily calculated. An example of the FI CDU model is presented. The FI-based refinery planning model is then developed and tested with a refinery planning example. The results are compared to the common fixed yield and swing cuts models. The FI refinery planning model predicted higher profit based on different crude purchase decision. Despite an order of magnitude increase in the problem size, the FI planning model did not require significantly longer solution times. DEWEY : 660 ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=24199903

Refinery Production Planning / Abdulrahman M. Alattas in Industrial & engineering chemistry research, Vol. 51 N° 39 (Octobre 2012) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 51 N° 39 (Octobre 2012) . - pp. 12852-12861 Titre : Refinery Production Planning : Multiperiod MINLP with Nonlinear CDU Model Type de document : texte imprimé Auteurs : Abdulrahman M. Alattas, Auteur ; Ignacio E. Grossmann, Auteur ; Ignasi Palou-Rivera, Auteur Année de publication : 2012 Article en page(s) : pp. 12852-12861 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Mathematical  programming  Modeling  Mixed  integer  programming  Non  linear  programming  Production  planning  Refinery Résumé : In a previous paper, Alattas, Grossmann, and Palou-Rivera (2011) developed a single-period, nonlinear programing refinery planning model using the fractionation index (FI) for the crude distillation unit (CDU) equations. In this paper, the single period model is modified to a mixed-integer nonlinear programming (MINLP) model to determine the sequencing, changeovers, and processing times of crude oils over multiple time periods. The MINLP equations include traveling salesman problem constraints to generate the crude oil sequences that maximize profit. Moreover, the disjunction for the fractionation index (FI) is formulated with mixed integer constraints as opposed to the Heaviside function formulation of the previous work. The resulting model is shown to be robust and relatively fast. When subcycles arise, they are eliminated by adding appropriate subtour elimination constraints. Examples with up to 5 crude oils and 6 weeks time horizon are presented to illustrate the application of the proposed model. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26419242 [article] Refinery Production Planning : Multiperiod MINLP with Nonlinear CDU Model [texte imprimé] / Abdulrahman M. Alattas, Auteur ; Ignacio E. Grossmann, Auteur ; Ignasi Palou-Rivera, Auteur . - 2012 . - pp. 12852-12861. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 51 N° 39 (Octobre 2012) . - pp. 12852-12861 Mots-clés : Mathematical  programming  Modeling  Mixed  integer  programming  Non  linear  programming  Production  planning  Refinery Résumé : In a previous paper, Alattas, Grossmann, and Palou-Rivera (2011) developed a single-period, nonlinear programing refinery planning model using the fractionation index (FI) for the crude distillation unit (CDU) equations. In this paper, the single period model is modified to a mixed-integer nonlinear programming (MINLP) model to determine the sequencing, changeovers, and processing times of crude oils over multiple time periods. The MINLP equations include traveling salesman problem constraints to generate the crude oil sequences that maximize profit. Moreover, the disjunction for the fractionation index (FI) is formulated with mixed integer constraints as opposed to the Heaviside function formulation of the previous work. The resulting model is shown to be robust and relatively fast. When subcycles arise, they are eliminated by adding appropriate subtour elimination constraints. Examples with up to 5 crude oils and 6 weeks time horizon are presented to illustrate the application of the proposed model. ISSN : 0888-5885 En ligne : http://cat.inist.fr/?aModele=afficheN&cpsidt=26419242