Bi-Objective Optimization of Interplant Integration Using Pinch Analysis

Water scarcity has led process industries to seek measures, such as in-plant and interplant recovery, for its efficient utilization. While considering interplant integration, mere water conservation can incur substantial investment cost due to a large number and distance of pipelines required as well as pumping costs associated with interplant flows. The interplant flow, and hence the costs associated with it, can be reduced by adding some amount of fresh water. The primary objective of this study is to explore the trade-offs between fresh water consumption and the interplant flow. A novel method, based on the extensions of Pinch analysis, is developed to accurately capture the trade-offs through Pareto optimal solutions. The graphical and algebraic nature of the developed technique provides efficient solutions with enhanced visualization. The method is illustrated through examples of water and hydrogen allocation networks.