Basic Introduction to Cooling Towers

A cooling tower is a heat exchanger, inside of which heat is withdrawn from the water by contact between the water and the air. Cooling towers use water evaporation to reject heat from processes such as cooling the circulating water used in oil refineries, chemical plants, power plants, steel mills and food processing plants.

An industrial water cooling tower extracts waste heat to the atmosphere though the cooling of a water stream to a lower temperature. Towers that use this process are called evaporative cooling towers. The heat dissipation can be carried out using air or evaporation of water. Natural air circulation or forced air circulation is used to maintain the required efficiency of operation of the tower and the equipment being used in the process.

The process is called “evaporative” because it allows a small portion of the water being cooled to evaporate into a moving air stream, providing significant cooling to the rest of that water stream. The heat from the water stream transferred to the air stream raises the air’s temperature and its relative humidity to 100%, and this air is discharged to the atmosphere.

Evaporative heat rejection devices – such as industrial cooling systems – are commonly used to provide significantly lower water temperatures than achievable with “air-cooled” or “dry” heat rejection devices, like the radiator in a car, thereby achieving more cost-effective and energy efficient operation of systems in need of cooling.

Industrial water cooling towers vary in size from small roof-top units to very large hyperboloid (hyperbolic) structures that can be up to 200 meters tall and 100 meters in diameter, or rectangular structures that can be over 15 meters tall and 40 meters long. Smaller towers (package or modular) are normally factory-built, while larger ones are typically constructed on site in various materials.

Post time: Nov-01-2020