Scheduling of storage and transfer tasks in oil refineries by using fuzzy optimization

A decision process is often used to schedule a task that should be executed taking in account its processing sequence and time. However, the processing time of an operation is often uncertain. Therefore, a scheduling program should be supported by decision systems, especially those using optimization techniques. In this work, time delays are also considered by using fuzzy optimization techniques. This paper proposes a scheduling for transfer and storage operations by considering products to be transferred among tanks through pipelines in a refinery. The proposed model is based on mixed integer linear programming (MILP) with continuous time representation. However, delays in operation times were represented by soft constraints, not found in traditional MILP models.