Desalination

Desalination is a process that removes mineral components from <a href="/facts/Saline_water/Tgw5AgL8">saline water</a>. More generally, desalination is the removal of salts and minerals from a substance. One example is <a href="/facts/Soil_salinity_control/YMaPJscM">soil desalination</a>. This is important for agriculture. It is possible to desalinate saltwater, especially <a href="/facts/Seawater/fRBJjbws">sea water</a>, to produce water for human consumption or irrigation. The by-product of the desalination process is <a href="/facts/Brine/xsN2GcLF">brine</a>. Many seagoing ships and <a href="/facts/Submarine/6fhcAKHV">submarines</a> use desalination. Modern interest in desalination mostly focuses on cost-effective provision of <a href="/facts/Fresh_water/xMP2TxwI">fresh water</a> for human use. Along with recycled <a href="/facts/Wastewater/g6Bn8xvT">wastewater</a>, it is one of the few <a href="/facts/Water_resources/2j7FJlLE">water resources</a> independent of rainfall.
Due to its energy consumption, desalinating sea water is generally more costly than fresh water from <a href="/facts/Surface_water/KQCY5RcY">surface water</a> or <a href="/facts/Groundwater/JYM2IDS2">groundwater</a>, <a href="/facts/Reclaimed_water/h1MSULMp">water recycling</a> and <a href="/facts/Water_conservation/DqnU0I0Y">water conservation</a>; however, these alternatives are not always available and depletion of reserves is a critical problem worldwide. Desalination processes are using either thermal methods (in the case of <a href="/facts/Distillation/plDvUMxn">distillation</a>) or membrane-based methods (e.g. in the case of <a href="/facts/Reverse_osmosis/U3EJPFHN">reverse osmosis</a>).: 24 
An estimate in 2018 found that "18,426 desalination plants are in operation in over 150 countries. They produce 87 million cubic meters of clean water each day and supply over 300 million people.": 24  The energy intensity has improved: It is now about 3 kWh/m3 (in 2018), down by a factor of 10 from 20–30 kWh/m3 in 1970.: 24  Nevertheless, desalination represented about 25% of the energy consumed by the <a href="/facts/Water_sector/1Xgk5CCF">water sector</a> in 2016.: 24

Desalination open-in-new

Desalination