Comprehensive Energy and Exergy Analysis of a Pressurized Water Reactor Driven Multi-Stage Flash Desalination Plant

Abstract

Nuclear energy-based seawater desalination is an environmentally friendly freshwater production approach. This study introduces a novel thermodynamic model integrating a pressurized water reactor’s (PWR) secondary cycle with a multi-stage flash (MSF) desalination facility to enhance freshwater production. The impacts of the design and operating conditions on thermal efficiency, utilization factor, gain output ratio, exergy efficiency, coefficient of ecological performance for cogeneration and exergy destruction factor are investigated. Results reveal that a higher live steam temperature and a reheater mass flow rate ratio is preferable for a better nuclear desalination performance. A larger freshwater production capacity is preferable for a better utilization factor, however increasing the capacity tends to decrease thermal efficiency, coefficient of ecological performance for cogeneration and exergy destruction factor. The selection of steam extraction location is important for very large scale plants, and the outlet of moisture separator is determined to be the best option. Parametric analysis shows that plant’s performance can be significantly improved by adjusting the design conditions. Thermal and exergy efficiencies of an optimized plant configuration are 3.01% and 4.70% higher, respectively as compared to a base plant. It is also found that steam generator and MSF unit cause 3.2% and 82% of the total irreversibility rate of PWR’s secondary cycle and MSF facility, respectively, and have the highest irreversibility rates for these sections of the plant.