Indexed by:期刊论文

Date of Publication:2020-09-09

Journal:INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH

Volume:59

Issue:36

Page Number:16017-16028

ISSN No.:0888-5885

Abstract:A heat exchanger network (HEN) plays an important role in the chemical process industry owing to its significant effect in energy recovery. A compression-absorption cascade refrigeration system (CACRS) is a promising technique for energy saving, which is able to utilize the process waste heat to generate cooling energy in different grades. The integrated design and optimization of HEN and CACRS can further improve waste-heat utilization and energy conversion efficiency. However, it is still very challenging to achieve a good integrating performance. To address the issue, an optimization-based method is proposed here that enables the simultaneous determination of the structure of HEN and the operating condition of CACRS. First, an improved superstructure is presented, considering various possibilities in matching, coupling, and system configurations. Based on the superstructure, a mixed-integer non-linear programming model is formulated for optimizing both the network structure and the operating variables, with the objective of minimizing the total annualized cost. Therein, the thermodynamic model of CACRS is included to obtain the optimal CACRS operating condition automatically. Finally, two cases are investigated to illustrate the advantage of the proposed method in improving economic performance and energy conversion efficiency.