Int. J. Process Systems Engineering, Vol. 1, Nos. 3/4, 2011 237 Copyright © 2011 Inderscience Enterprises Ltd. Integration and coordination of multisite refinery and petrochemical networks under uncertainty A. Elkamel* and K. Al-Qahtani Department of Chemical Engineering, University of Waterloo, Ontario, N2L 3G1, Canada E-mail: aelkamel@uwaterloo.ca E-mail: kalqahta@uwaterloo.ca *Corresponding author Abstract: In this paper we extend upon our previous work on the deterministic design of an optimal network for the integration of multisite refinery and petrochemical systems to incorporate uncertainty. A two-stage stochastic mixed-integer program with the objective of minimising the refining cost over a given time horizon and maximising the added value by the petrochemical network is proposed in this paper. Uncertainties considered in this study are in terms of imported crude oil price, refinery product price, petrochemical product price, refinery market demand, and petrochemical lower level product demand. The proposed method adopts the sample average approximation (SAA) method for scenario generation and optimal gab statistical bounding. The model performance is tested on an industrial case study of multiple refineries and a polyvinyl chloride (PVC) complex. Keywords: planning under uncertainty; coordination; petrochemical planning; multirefinery optimisation. Reference to this paper should be made as follows: Elkamel, A. and Al-Qahtani, K. (2011) ‘Integration and coordination of multisite refinery and petrochemical networks under uncertainty’, Int. J. Process Systems Engineering, Vol. 1, Nos. 3/4, pp.237–265. Biographical notes: Ali Elkamel is currently a Professor of Chemical Engineering at the University of Waterloo. He holds a BS in Chemical and Petroleum Refining Engineering and a BS in Mathematics from Colorado School of Mines, an MS and a PhD in Chemical Engineering from the University of Colorado-Boulder and Purdue University, respectively. He teaches graduate and undergraduate courses on optimisation techniques, mathematical methods for chemical engineers, applied statistics, numerical methods, systems engineering, and engineering economy. He is a member of different scientific societies and published in many refereed international journals and conferences. Khalid Al-Qahtani is currently a PhD candidate at the Chemical Engineering Department, University of Waterloo. He obtained his BSc in Chemical Engineering from KFUPM, Saudi Arabia in 1999. He has served for more than six years in the petroleum industry as a Process and Project Engineer spanning the area of oil treatment, gas processing and refining operations. His research interests include planning under uncertainty of single and multisite facilities in the petroleum refining and petrochemical industry.