Fast Bypass Selection Method during the Heat Exchanger Network Synthesis

Abstract

Abstract This paper provides a new and fast method to select bypass during the heat exchanger network (HEN) synthesis stage. An indicator, namely disturbance over utility (DoU), was introduced to measure the maximum simultaneous disturbance rejection ability over the utility consumption. Together with a physical distance study, they can select the bypass placement fast and efficiently. DoU can select preferable heat exchangers to place bypass, and compare different HENs. For a given HEN with specified bypass strategies, the higher the DoU is, the larger the disturbance rejection ability per unit utility consumption, which was solved by a non linear programming (NLP) model. The physical distance study utilizes the structural information to discard potential inverse response and compare response time of different bypasses. The method has been applied into two alternative HENs, illustrating the process to select better HEN and find preferable bypass placement strategies. The main goal of this work is to contribute to HENs synthesis, by proposing a fast and efficient bypass selection method to decide the control structure.