How does a cooling tower work?
How does a cooling tower work?
A cooling tower is a heat exchanger, inside of which heat is withdrawn from the water by contact between the water and the air. The heat transfer occurs through the heat exchange between air and water and through the evaporation of a small part of the water that needs to be cooled. This will allow to cool down to a temperature lower than the ambient temperature, which is an important advantage compared to dry coolers.
Consequently, a cooling tower is not a chimney producing smoke. The mist which can be seen above a cooling tower is regular steam with the same composition as a normal cloud.
Types
Cooling towers can be divided into types in different ways: based on the fan type, shape, water flow or efficiency, cooling water composition... The main classification tends to be based on the cooling circuit type, which determines the exact operation of the cooling tower.
The basic cooling tower classification tends to be based on the following criteria:
- Natural or mechanical draft
- Induced or forced draft
- Open, closed or hybrid cooling circuit (adiabatic cooler)
The cooling circuit type determines the exact heat exchange process.