Continuous time representation approach to batch and continuous process scheduling. 2. Computational issues

The first part of this series presented a general mathematical framework fo r describing a wide variety of scheduling problems arising in multiproduct/ multipurpose batch and continuous chemical plants. The problem was formulat ed as a large mixed integer nonlinear programming model (MINLP). A techniqu e that exploits the characteristics of the problem in order to reduce the a mount of required computation is reported. The technique is based on the Ba yesian heuristic (BH) approach to discrete optimization. The BH approach al lows incorporation of different heuristics into the solution process. A mat erial requirement planning (MRP) heuristic is employed in the work reported herein. Computational examples are presented to illustrate the applicabili ty of the method to the scheduling of multipurpose plants under a variety o f operational conditions.