drinkwaterdesalination

Drinking water desalination is the process of removing dissolved salts and other contaminants from saline or brackish water to produce potable water. It is used where freshwater supplies are limited or stressed, with feedwater sources typically including seawater and brackish groundwater. The resulting water is treated to meet drinking water standards, often followed by remineralization to restore essential minerals and stabilize pH.

The most common method for large-scale desalination is reverse osmosis, which uses high pressure to force water through semi-permeable membranes that block salts. Other approaches include thermal distillation methods such as multi-stage flash and multi-effect distillation, as well as electrodialysis and electrodeionization for lower-salinity feeds. Emerging options include forward osmosis and hybrid systems that combine techniques to improve efficiency.

A desalination plant generally involves intake and pretreatment to remove particulates and biofouling, the desalination step itself, and post-treatment such as disinfection and remineralization before distribution. Energy requirements and capital costs vary by technology and feedwater salinity; reverse osmosis is typically more energy-efficient for seawater, but overall economics depend on local conditions. Environmental considerations include brine disposal, intake impacts on marine life, and the need for careful water quality monitoring.

Applications and policy context: desalination provides a reliable water source for many coastal and drought-prone regions, though it can entail higher costs than conventional supplies. It is deployed in countries such as Saudi Arabia, the United Arab Emirates, Israel, Kuwait, Spain, Australia, and portions of the United States and Europe, with ongoing efforts to reduce energy use and environmental footprint.