Metaheuristic multiobjective optimization approach for the scheduling of multiproduct plants.

BONFILL, ANNA; ARBIZA, MARÍA J.; CANTÓN, JORDI; GUILLÉN, GONZALO; MELE, FERNANDO D.; ESPUÑA, ANTONIO; PUIGJANER, LUIS

Praga, República Checa

Conferencia; 7th Conference on Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction (PRES 2004); 2004

European Federation of Chemical Engineering

This work introduces a framework able to deal with the scheduling problem but explicitly and simultaneously considering several objectives, these are the makespan and the environmental and financial impact of the resulting schedule. In such strategy, a set of multiobjective optimization algorithms is combined with a scheduling tool which includes a temporization module, a environmental module and a financial module that allow the evaluation of the different objective functions of the explored solutions. LCA (Life Cycle Assessment) criteria is included to evaluate the environmental impact associated with the different schedule alternatives, while the financial performance of the schedule is measured as the integral of the available cash associated to it. Because of the non-linearities of the problem equations and the integer characteristics of some of the decision variables, exact optimal solution is very hard to reach, therefore multiobjective versions of metaheuristic algorithms are used. The benefits of the proposed strategy are illustrated using a representative case study of a simple multiproduct batch chemical plant.