Parametric investigation and performance optimization of a MED-TVC desalination system based on 1-D ejector modeling

Abstract

In recent decades, desalination has gained widespread recognition as a viable and reliable source of non-conventional fresh water. Desalination is the most expensive and energy-intensive method of water management. Researchers use various desalination and purification methods to provide fresh water to treat wastewater and seawater. This study conducted a parametric analysis and multi-objective optimization of a Three-effect Desalination with Thermal Vapour Compression (MED-TVC) system that provides the required energy with heat recovery. Influential system performance factors, including AR, Pc, Peff3, ΔTcond, and heat source temperature (THS), were evaluated using a comprehensive program built on energy analysis, exergy, and exergoeconomics. The findings demonstrated that increasing the recycled heat temperature from 120 to 180 °Cexerted a positive effect on freshwater production, energy efficiency, and Żtot, respectively. In addition, it was determined that the values of GOR, Żtot, and ṁd were 2.118, 3845 $/yr, and 30.33 g/s, respectively. Furthermore, the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS) approach was employed for multi-objective optimization to improve gained output ratio (GOR) and energy efficiency and lower costs relating to changes in the AR, Pc, and Peff3 parameters. The optimum points at THS = 160 °C were 7.524, 25.02 kPa, and 12.14 kPa, respectively. Moreover, the TVC system yielded the lowest cost (estimated at 35.33 $/yr), and the second effect yielded the highest cost (calculated at 562.6 $/yr). Finally, calculated values for GOR, Żtot, and ṁd were 2.18, 3845 $/yr, and 30.33 g/s, respectively.