A cooling tower is a specialized heat exchanger in which air and water are brought into direct contact with each other in order to reduce the water’s temperature. As this occurs, a small volume of water is evaporated, reducing the temperature of the water being circulated through the tower. Water, which has been heated by an industrial process or in an air-conditioning condenser, is pumped to the cooling tower through pipes.
The water sprays through nozzles onto banks of material called “fill,” which slows the flow of water through the cooling tower, and exposes as much water surface area as possible for maximum air-water contact. As the water flows through the cooling tower, it is exposed to air, which is being pulled through the tower by the electric motor-driven fan.