Optimal campaign planning scheduling of multipurpose batch semicontinuous plants .2. A mathematical decomposition approach

In the companion paper, a single-level mathematical formulation has been presented describing the multiple campaign planning/scheduling problem in considerable generality. However, the resulting mixed integer linear programming model is too large to be computationally tractable for many cases of practical interest. In this paper, we present a rigorous decomposition approach to the solution of this problem and demonstrate its effectiveness by applying it to a number of illustrative examples. In addition, we consider ways in which the structure of the constituent mathematical models of the decomposition scheme can be exploited to reduce their sizes and the associated integrality gaps. Examples illustrating the applicability of the overall approach are also presented.