Thermoeconomic investigation of coupling MED-TVC with a combined cycle power plant

Abstract

Freshwater generation has always been one of the most important issues in human communities that coincided with population increase in different areas. Freshwater desalination technology can be one of the most effective methods in utilizing power plants heat recovery. Iran has a high potential to use this technology due to the shortage of fresh water resources on the one hand and several thermal power plants in the coastal areas of North and South on the other hand. In this study, according to the project of transferring Caspian Sea water to the central plateau of Iran and the necessity of water desalination before transferring, the studied topics are exergy destruction rate in different components of the cycle and rate of both profit and loss which results from coupling thermal desalination to Neka power plant. Results have shown that the maximum exergy destruction cost occurred in thermocompressor and then in condenser. Furthermore, if at least 2,000 cubic meters water per day, equivalent to 730,000 cubic meters in a year, was daily generated and sold with trade tariffs, power plant had acquired significant benefit of 28,732 ($/year), in addition to compensation for losses resulting from reduced electricity generation and if the maximum possible amount of 7,215 cubic meters per day equivalent to 2,633,457 cubic meters in a year of water was daily generated, the power plant had gained a significant benefit about 380,786.25 ($/year).

Keywords:

• Seawater desalination
• Multi-effect desalination with thermal vapor compressor
• Combined cycle power plant
• Exergy destruction
• Thermo compressor
• Thermoeconomic
• Boiling point elevation