Integrated Scheduling for Polyvinyl Chloride Processes

This study considers a scheduling algorithm and mathematical models for a real polyvinyl chloride (PVC) plant. According to general rules of the PVC plant, the basic PVC scheduling model is formulated as mixed integer linear programming (MILP). This model includes production, inventory management, packing, and shipment processes. The basic PVC scheduling model is customized for two PVC production processes with different characteristics, resulting in two detailed PVC scheduling models. An optimization algorithm has been developed to solve these scheduling models. This algorithm is a hybrid algorithm combining the genetic algorithm for integer programming (IP) and the interior point method for linear programming (LP). A heuristic technique has also been developed to reduce the number of solving LPs. Finally, the optimized results of the models were analyzed.