Globally optimal simultaneous heat exchanger network synthesis and basic heat exchanger design

In this article, we extend a previously developed globally optimal enumeration methodology for the synthesis of heat exchanger networks (HENs) to include the basic design of heat exchangers (HEXs). The method addresses together all trade-offs between network structure, energy usage, and the basic design of the HEXs. Without loss of generality, we focus on shell-and-tube HEXs. Unlike previous approaches, such as Pinch Analysis, Metaheuristic methods, or Mathematical Programming, our procedure guarantees global optimality. The procedure is not iterative and does not present any convergence challenges. We enumerate HEN structures using a mixed-integer linear programming method and we use Set Trimming followed by sorting for the HEX design. In addition, because some network structures are incompatible with single shell exchangers, we use multiple shell exchangers in series. The comparison of the results of the proposed approach with solutions obtained using two alternative methods extracted from the literature indicates that considerable cost reductions may be obtained.