Planning and Scheduling Integration for the Multi-product Polymer Process
In this paper, a real-world planning and scheduling integration problem from the polyvinyl chloride (PVC) polymer production process is investigated. PVC is an important polymer and widely used as a raw material in various chemical engineering products. There is a great demand for PVC in chemical industry, so it is more profitable to apply scientific management decisions for its manufacturers. The process of PVC production is a multi-stage parallel hybrid of batch and continuous processes, which belongs to the general multiproduct process. According to the special characters of the process, this study presents a new continuous-time formulation for the planning and scheduling integration problem, including changeover, setup, production, and inventory management. The formulation gives rise to a mixed-integer linear programming (MILP) model. The number of event points is pre-postulated, and event times are defined by the setting-up of a product. Based on the concern of common resources, the time grid is uniform. The large size of the problem makes it difficult to get optimal solution efficiently using general Branch and Bound method. Investigating the polyhedron of the model, and adding some valid inequalities as cuts, the paper designs efficient optimal algorithm. Finally, analyze the optimal result and compare with practice operations.
Planning Scheduling MILP PVC Valid Inequalities
Lijie Sua Lixin Tang Qi Tang Hui Jin
Logistics Institute,College of Information Science and Engineering,Northeastern University,Shenyang,110004,China
国际会议
西安
英文
2007-08-15（万方平台首次上网日期，不代表论文的发表时间）