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The desalination of high-salt wastewater or brackish water is typically carried out through either of the following two main processes: (a) by evaporating water vapor or (b) by using semipermeable membranes to separate fresh water from the concentrate. During phase transformation or heat treatment, the distillation of high-salt wastewater is achieved by utilizing a heat source. In membrane processes, electricity is used to drive high-pressure pumps or to create an electric field to separate ions. The major commercial desalination methods based on thermal energy are multi-stage flash (MSF), multi-effect distillation (MED), and thermal vapor compression (TVC). The MSF and MED processes consist of many successive stages of continuously reducing temperature and pressure. The multi-stage flash evaporation process is based on the generation of vapor from the high-salt wastewater or brine due to sudden depressurization (flash evaporation) when the high-salt wastewater enters the vacuum chamber. Repeat this process gradually while continuously reducing the pressure. Steam condensation is achieved through regenerative heating of the feedwater. This process requires an external steam supply, usually at a temperature of around 100°C. The maximum operating temperature is limited by the formation of scale, and therefore the thermodynamic properties of this process are also restricted. In a multi-effect distillation system, steam is generated by heating high-salt wastewater at a given pressure in each of a series of cascaded chambers. The steam or “effect” generated in one stage is used to heat the brine in the next stage, which is at a lower pressure. The thermal performance of these systems is proportional to the number of stages, and the capital cost limits the number of stages that can be used. In a thermal steam compression system, after water vapor is generated from a salt solution, high-pressure steam is used to thermally compress the vapor, which is then condensed to produce drinking water. The second category of important industrial desalination processes uses membrane technology, mainly reverse osmosis (RO) and electrodialysis (ED). Reverse osmosis uses a power-driven pump to increase the feed water pressure to the desired value. The required pressure depends on the salt concentration of the feed. Pumps are usually electrically driven. Used in reverse osmosis systems, which are currently the most economical desalination systems; the cost of producing water can be as high as US $3 per cubic meter for systems with smaller capacities (for example, plants with a capacity of 5 to 100 cubic meters per day). Furthermore, reverse osmosis equipment requires professionals for operation and maintenance. The electrodialysis process also requires electrical energy to induce ion migration through a suitable ion exchange membrane. Both reverse osmosis and electrodialysis can be used for seawater desalination; however, reverse osmosis is also competitive for the multi-stage flash process used in the desalination of large volumes of highly saline wastewater. The multi-stage flash process accounts for over 75% of heat-driven desalination processes, while reverse osmosis processes make up over 90% of membrane-based processes used for water production. Multi-stage flash evaporation units are typically capable of handling volumes ranging from 100,000 to almost one million cubic meters per day. In terms of operation, the largest reverse osmosis plant at present is the Ashkelon plant, with a capacity of 330,000 cubic meters per day. Other methods of desalination include processes such as ion exchange, liquid-liquid extraction, and gas hydrate processes. Unless high purity (total dissolved solids) is required for special applications