Title: Improving the operation of heat exchanger networks through exergy analysis
Authors: Bahar Saeb Gilani; Tatiana Morosuk
Addresses: Institute for Energy Engineering, Technische Universität Berlin, Marchstrasse 18, 10587, Berlin, Germany ' Institute for Energy Engineering, Technische Universität Berlin, Marchstrasse 18, 10587, Berlin, Germany
Abstract: In this paper a procedure is introduced to compare alternative control configurations for the optimal operation of heat exchanger networks. The method uses the advantage of exergy analysis in quantifying the thermodynamic inefficiencies of heat exchangers and mixers as the fundamental elements of heat exchanger networks. It is shown that in some cases solving the optimisation problem based on energy does not indicate any differences between alternative design configurations. Whereas solving the optimisation problem aiming at the minimum exergy destruction provides the missing information. It is also shown for the first time in this paper that applying exergy-based optimisation reveals further room for the improvement of the heat exchange network operation. By readjusting the manipulated variables of the control system, the total exergy destruction of the heat exchanger network can be reduced by over 6% for both studied design configurations.
Keywords: heat integration; heat exchanger network; exergy analysis; optimal operation; control configuration; online optimisation.
International Journal of Exergy, 2022 Vol.38 No.2, pp.202 - 217
Received: 01 Apr 2021
Accepted: 02 Oct 2021
Published online: 29 Jun 2022 *