DESIGN OF MULTIPURPOSE BATCH PLANTS WITH UNCERTAIN PRODUCTION REQUIREMENTS

The uncertainty involved in predicting product market trends may cause problems during batch plant design, with traditional approaches to this problem usually relying on simple risk analysis and the introduction of overdesign factors. We present a design procedure for batch plants where such uncertainty exists. It requires the specification of a variety of possible operating scenaria (such as different annual production requirements for all products). The plant design ensuing from the solution is able to cope with any one of the operating scenaria, without any arbitrary overdesign. The optimal solution to this problem is obtained by solving a multiperiod design problem, based on a detailed deterministic multipurpose plant design formulation. For large designs, and/or problems involving many different scenaria, the solution of this multiperiod problem may not be feasible. Consequently, efficient techniques for obtaining good upper and lower bounds on the solution are also presented.