Study on Zero-emission Desalination System Based on Mechanical Vapor Recompression Technology

AbstractA large amount of energy is consumed during the conventional large-scale evaporation desalination system. Especially for the large seawater desalination process for generating freshwater, a large amount of rich-salt water is generated, and there exists a big risk to break the ecological balance of the surrounding waters due to the high salinity of discharged seawater. In this paper, the conventional evaporation desalination technologies are examined, and two zero-emission desalination systems based Mechanical vapor compression (MVR) technology, including a single-stage and a double-state zero-emission MVR desalination system are proposed. Via integrating the components models of the zero-emission desalination system, energy saving of the two proposed systems is investigated through comparing with the conventional evaporation desalination system under the same conditions, and then the key operation parameter of the proposed system is optimized via the pinch analysis method. Finally an energy and an exergy analysis are conducted for the proposed system to study its thermodynamic energy saving potential