Multiple time grid continuous-time formulation for the short term scheduling of multiproduct batch plants

Abstract

This paper presents a new multiple time grid continuous time MILP model for the shortterm scheduling of single or multistage, multiproduct plants. It can handle both release and due dates and different objective functions efficiently, such as the minimization of total cost, total earliness or makespan. This formulation is compared to other existing MILP approaches with the results showing that the proposed formulation is much more efficient than its uniform time grid counterpart. It is also better than models that use global precedence sequencing variables for single stage problems, while performing similarly for multistage problems.