Multiperiod optimization of closed seawater circulating cooling water system

Abstract

Traditional open circulating cooling water systems use a lot of water and electricity to remove waste heat. In coastal areas, closed seawater circulating cooling water systems have been used as an alternative to improve cooling efficiency. However, a comprehensive comparison of the design and advantages of the two types of cooling systems is lacking. Also, the best way to match and optimize the seawater system with the circulating water system in the closed seawater circulating cooling water system has not been fully explored. In this paper, a closed seawater cooling system under multiperiod is constructed, taking into account monthly changes in environmental factors. The mixed integer nonlinear programming model is solved by using GAMS software to evaluate and compare the economics and operability of the two cooling schemes. Meanwhile, the matching relationship of the internal subsystems of the closed seawater circulating cooling water system after coupling the air coolers is studied in depth, and the cooling load is allocated reasonably. The cases show that seawater cooling saves 9.22% of circulating water and reduces the total cost by 8.93% compared with cooling tower. The cost of the closed seawater cooling system can be reduced by 24.37% after coupling air coolers, and there is a direct corresponding matching relationship between circulating water and seawater.

Graphical abstract

Keywords

closed circulating cooling water system / multiperiod / seawater / design

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Acknowledgements

Financial support from the National Natural Science Foundation of China under Grant (Grant Nos. 22393954 and 22078358) is gratefully acknowledged.

Competing interests

The authours declare that they have no competing interests.

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2025 Higher Education Press