New alternatives in the design and planning of multiproduct batch plants in a multiperiod scenario

Abstract

New alternatives for the simultaneous design and planning of multiproduct batch plants in a multiperiod scenario are presented in this article. This formulation allows the flexible configuration of the plant in every time period for each product considering the assignment of parallel units of different sizes operating either in-phase or out-of-phase. Capacity expansion during the time horizon is also allowed in order to satisfy new variable requirements. For each batch stage, following the usual procurement policy, units are selected from a set of standard and discrete sizes that are available to perform each operation. The model is formulated through a mixed-integer linear programming (MILP) formulation that maximizes the net present value of profit. From the planning point of view, product sales, raw materials purchases, inventories, waste disposal, and late deliveries are taken into account. Thus, this model simultaneously solves both design and production planning for given forecasts of product demands and pricing in each time period. © 2007 American Chemical Society.