A desalination plant is a facility that converts salt sea water into water suitable for human consumption, or for industrial and irrigation uses.

There are several desalination processes:

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• Distillation with a still, (a process similar to that which occurs naturally during the water cycle) consisting of boiling seawater in a still, collecting the steam and condensing it to obtain fresh water.

• Solar distillation: Imitating the water cycle, it consists of evaporating seawater in large facilities with roofs where it condenses and is collected in the form of fresh water.

• Reverse osmosis: It is the most used process and consumes less energy than the rest as it is based on the use of semipermeable membranes that let water pass, but not salt.

• Nanofiltration: Process similar to reverse osmosis, but in which nanotube membranes of greater permeability are used that, in addition to removing salt, also eliminate traces of contaminants.

• Electrodialysis: The process by which fresh water is obtained by moving salt water through electrically charged membranes that trap salt ions dissolved in water.

• Formation of gaseous hydrates: Process in which salt water is combined with gaseous hydrates such as, for example, propane, at high pressure and low temperature. Once combined, the temperature is raised, obtaining fresh water free of salts and impurities.

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In any of the above desalination procedures, a water catchment system is necessary and in the last four described, a brine evacuation system.

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Water collection and brine discharge systems have evolved over the years mainly due to the need to adapt to new environmental regulations, improvements in technological innovation and increased efficiency of new desalination plants.