Design and production planning of multiproduct batch plants under uncertainty

MORENO, MARTA SUSANA; MONTAGNA, JORGE MARCELO

Bahía Blanca

Congreso; III Congreso de Matemática Aplicada, Computacional e Industrial (III MACI 2011); 2011

AR-SIAM(Sección Argentina de SIAM-Society for Industrial and Applied Mathematics-USA) y ASAMACI (Asociación Argentina de Matemática Aplicada, Computacional e Industrial)

A two-stage stochastic multiperiod LGDP (Linear Generalized Disjunctive Programming) model has been developed for the overall production planning and design of multiproduct batch plants. Both problems are encompassed considering uncertainty in product demands represented by a set of scenarios. The design variables are modeled as here-and-now decisions which are made before the demand realization, while the production planning variables are delayed in a wait-and-see mode to optimize in the face of uncertainty. The proposed model determines the structure of the batch plant (both kinds of unit duplication, in series and in parallel) and the unit sizes, together with the production planning decisions (e.g. quantities to be produced, policy of inventory, purchases of raw materials, and sales of products) in each time period within each scenario. Also, this model allows the incorporation of new equipment items at different periods. The objective is to maximize the expected net present value of the benefit. In order to assess the advantages of the proposed formulation, an extraction process that produces oleoresins is solved.