State-of-the Art in Short-Term, Medium-Term, and Reactive Scheduling for Large-Scale Batch and Continuous Processes

Scheduling is a decision making process to determine when, where, how to produce a set of products given requirements in a specific time horizon, a set of limited resources, and processing recipes. The research area of batch and continuous process scheduling has received great attention from both the academia and the industry in the past two decades. This is motivated by the increasing pressure to improve efficiency and reduce costs and by the significant advances in relevant modeling and solution techniques and the rapidly growing computational power. In multi-product and multipurpose batch, semi-continuous, and continuous plants, different products are manufactured via the same or similar sequence of operations by sharing available pieces of equipment, intermediate materials and other production resources. The inherent operational flexibility of these plants provides the platform for great savings reflected in good production schedules. In this talk, we will present an overview of the exciting developments in the scheduling of multi-product, multipurpose batch and continuous processes. In addition to the discrete-time approaches, pioneering continuous-time models will be presented. Based on the continuous-time representation, existing approaches were classified into slot-based, global event-based, and unit-specific event-based models. A comparative study of different continuous-time models will be presented with respect to some benchmark problems from the literature for short-term scheduling of batch and continuous plants. Important characteristics of batch and continuous chemical processes that pose challenges