Overview of planning and scheduling for enterprise-wide optimization of process industries

Enterprise-wide optimization (EWO) is a new emerging area that lies at the interface of chemical engineering and operations research, and has become a major goal in the process industries due to the increasing pressures for remaining competitive in the global marketplace. EWO involves optimizing the operations of supply, production and distribution activities of a company to reduce costs and inventories. A major focus in EWO is the production optimization, which often requires the use of nonlinear process models. Major operational items include production planning, scheduling, real-time optimization and control. This paper provides an overview of major challenges in the development of deterministic and stochastic linear/non linear optimization models and algorithms for the optimization of entire supply chains that are involved in EWO problems. We specifically review two major challenges: (a) modeling of planning and scheduling, (b) multiscale optimization. We consider two major applications in batch scheduling and crude oil scheduling. We conclude with a brief discussion on future directions.