10.1021/ie504835b.s007 Nikisha K. Shah Nikisha K. Shah Nihar Sahay Nihar Sahay Marianthi G. Ierapetritou Marianthi G. Ierapetritou Efficient Decomposition Approach for Large-Scale Refinery Scheduling American Chemical Society 2015 task assignment sequence iteration delivery scheduling problem product demand commitments Efficient Decomposition Approach production unit scheduling problem refinery production unit operations refinery case study demurrage violations algorithm solution 2015-10-21 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Efficient_Decomposition_Approach_for_Large_Scale_Refinery_Scheduling/2119291 This paper proposes a heuristic algorithm for integrated scheduling of refinery production unit operations and finished product blending and delivery operations. To apply the proposed iterative algorithm, the integrated oil-refinery scheduling problem is decomposed into a production unit scheduling problem and a finished product blending and delivery scheduling problem. The goal of the algorithm is to obtain a feasible solution that satisfies product demand commitments with minimum demurrage violations while minimizing run-mode changeover cost, inventory cost, and penalties subject to product and logistics giveaways. The proposed algorithm provides a feasible solution at the end of each iteration, and to obtain solution without demurrage violations, a set of integer cuts are generated at the end of an iteration to eliminate current task assignment sequence for a multipurpose blend unit. The applicability of the algorithm is illustrated by a realistic large-scale refinery case study producing diesel and jet fuel. Significant savings are realized in the computational effort.