The primary use of large, industrial cooling towers is to remove the heat absorbed in the circulating water systems in the thermoelectric power, refineries, petrochemical and other industries.
Cooling these plants requires considerable amounts of water; typically 80% of the total consumption of freshwater in coal-based power plants, and 50% of the fresh water consumption in refineries, is used for cooling.
In recent years, due to water scarcity, stricter regulations on disposal and increasing costs of fresh water intake, reuse and/or Zero Liquid Discharge (ZLD) treatments of blowdown water have become critical for these plants, and to the environment.