ABSTRACT
The scope of this chapter is concerned with the petroleum supply network operated by one or more oil company, in which the crude oil is consumed to produce ethylene, propylene, liquefied petroleum gas, butadiene, benzene, toluene, xylene, gasoline, kerosene, diesel, and other by-products. These petrochemical products are usually manufactured with a cluster of strategically located conversion refineries. A complete petroleum supply chain consists of at least 13 different types of production units, i.e., the atmospheric distillation units, the vacuum distillation units, the cokers, the fluid catalytic cracking units, the naphtha crackers, the butadiene extraction units, the hydro-treaters, the aromatics extraction units, the reforming units, the xylene fractionation units, the parex units, the xylene isomar units, and the tatory units. Traditionally, the production plan of an industrial supply chain is created first and a compatible schedule is then identified accordingly. Since the detailed scheduling constraints are often ignored in the planning model, there is no guarantee that an operable schedule can be obtained with this hierarchical approach. To address this issue, a single mixed-integer linear program (MILP) has been formulated in this chapter to coordinate various planning and scheduling decisions for optimizing the supply chain performance. Solving this MILP model yields the proper procurement scheme for crude oils, the schedules for producing various petrochemical products, and the corresponding logistics. The appropriate sources (suppliers) of raw materials, the economic order quantities, the best purchasing intervals, and also the transportation schedules can be identified accordingly. In particular, the optimal production schedule of olefins, aromatics, and other petrochemical products over the specified planning horizon is configured by selecting throughput, operating conditions, and technology option for each unit in the chain, by maintaining the desired inventory level for each process material, by securing enough feedstock, and by delivering appropriate amounts of products to the customers. For the sake of illustration convenience, the subsequent benefit allocation issues in the petroleum supply network are addressed in a separate chapter in Chapter 9.
