All thermal power plants produce waste heat as a byproduct of electrical energy. The cooling towers for US thermoelectric power producers use more than 70 trillion gallons of water yearly. Cooling water must be treated to meet each individual site’s needs, which vary with the influent source water quality, type of boiler, discharge requirements and whether ‘used’ water is recycled within the plant. While in the past a combination of coagulation, flocculation and ion exchange resin beds have been used to create high purity water for steam,, more advanced water treatment including reverse osmosis, electrodeionisation, and UV treatment or ozonation for disinfection are used more and more for effective, chemical-free treatment with lower environmental impact..
Ozone and ultraviolet light can be used for controlling biological growth in power plant water intake.Non-chemical disinfection processes can minimise the use of toxic chemical traetment such as chlorine,.
Systems combining a series of treatments provide the most complete water treatment at the best price. Depending on the influent water and required product water purity, systems may include reverse osmosis, other membrane methods, mixed-bed ion exchange, EDI, ozone, UV and various combinations of these technologies.