Robust planning of multisite refinery networks: Optimization under uncertainty

This paper considers the problem of multisite integration and coordination strategies within a network of petroleum refineries under uncertainty and using robust optimization techniques. The framework of simultaneous analysis of process network integration, originally proposed by Al-Qahtani & Elkamel [Al-Qahtani, K., & Elkamel, A. (2008). Multisite facility network integration design and coordination: An application to the refining industry. Computers & Chemical Engineering. 32, 2198], is extended to account for uncertainty in model parameters. Robustness is analyzed based on both model robustness and solution robustness, where each measure is assigned a scaling factor to analyze the sensitivity of the refinery plan and integration network clue to variations. Parameters uncertainty considered include coefficients of the objective function and right-hand-side parameters in the inequality constraints. The proposed method makes use of the sample average approximation (SAA) method with statistical bounding techniques. The proposed model was tested on two industrial-scale studies of a single refinery and a network of complex refineries. Modeling uncertainty in the process parameters provided a practical perspective of this type of problems in the chemical industry where benefits not only appear in terms of economic considerations, but also in terms of process flexibility. (C) 2010 Elsevier Ltd. All rights reserved.