Techno-Economic and Exergetic Analysis and Optimization of Integrated MED- RO Desalination System in the Genaveh Combined Cycle Power Plant

Hybrid power and desalinated water generation systems with two Multi-Effect Distillation (MED) technologies and Reverse Osmosis (RO) are investigated for a combined-cycle power plant in this study. The generated steam enters MED from the low-pressure section of the Heat Recovery Steam Generator (HRSG) in the hybrid system. Seawater is divided into two sections after entering the MED condenser – one part is fed into MED and its process. The other is rejected after cooling in the condenser and turns back to the sea. A reverse osmotic desalination system is implemented in this study. In the present combined cycles, steam generated in the Low Pressure (LP) section enters the steam turbine. To reduce the generated power and increase desalinated water in MED and RO, exergy analysis and cycle optimization are required. The system is simulated and verified based on the available data on the model power plant. The results showed that by selecting 43 optimization parameters and applying constraints like acidification temperature, the integrated cycle's exergy efficiency could be raised by 50%. Under this condition, the water price is calculated to be 1.16 $/m3. Under hybrid conditions of the design power and freshwater cogeneration system, the present design's efficiency without optimization and its final cost is 48.8% and approximately 1.2 $/m3.