In the oil industry, any improvement in the planning and execution of the associated operations (e.g., production, storage, distribution) can generate considerable profits. To achieve this, the related activities need to be optimized. Within these activities, planning and scheduling occur at the different levels of the oil supply chain, from the strategic to the operational levels looking from global networks to sets of individual resources. This work looks into the planning, namely the assignment/ sequencing of activities that occur in a multiproduct, multipipeline system. The aim is to contribute to the definition of generic models that can help the decision-making process characterized by a high level of complexity. An approach formed by two mixed integer linear programming (MILP) formulations that act in sequence is proposed. The first generic MILP planning model calculates volumes for attending the necessary requirements on inventory management of the producer and consumer areas. As a result, this model defines the products and the total volumes to be transported in order to attain storage goals, while respecting operational constraints, demands of consumers, and pipeline capacity. Then, the planning model results are used by an MILP assignment and sequencing model, which splits the total volume into operational batches and determines the sequence of pumping for the batches during the available horizon. The developed approach is applied to a real-world pipeline network that includes 30 bidirectional multiproduct pipelines associated with 14 node areas: four refineries, two harbors, six depots/parks of pumps and valves, and two final clients.

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This paper presents a collaborative approach to the assignment and sequencing of batches in pipeline networks. The approach is based on the integration of a heuristic algorithm with a mixed integer linear programming (MILP) model. The pipeline-scheduling problem is solved using a hierarchical decomposition [Ind. Eng. Chem. Res.2015545077], but a new collaborative approach is proposed for assignment/sequencing tasks. At a first step, the proposed heuristic algorithm (assignment module) determines priorities for sending batches in order to respect deadlines. The algorithm encompasses an analysis of production and demand plans, inventories, and input and output of products in terminals, trying to use resources, namely tanks and pipelines, in an optimized form. This algorithm is used in cooperation with a proposed MILP sequencing model, which allows overcoming computation difficulties previously indicated by a traditional scheduling approach that tried to aggregate into the same monolithic MILP model assignment and sequencing decisions [Ind. Eng. Chem. Res.2012514591]. The proposed assignment/sequencing collaborative approach can be used to define operational batches with their volumes and routes in pipeline networks. Thus, the lot-sizing problem of batches in pipeline networks is addressed within the proposed paper. Tests were made in pipeline networks of different topologies. First, a small, but representative pipeline network is proposed and a data set for this network is made available for reproducibility purposes. Second, tests are made in a real-world pipeline network and results have been attained in computational times from seconds to few minutes.