Cooling towers are a crucial part of any building’s heat and water management system. In this article, we’ll talk about what they are, where they’re used, and how they work. Read on!
What are Cooling Towers?
Cooling towers are special heat exchangers that let water and air come in contact with each other to lower the temperature of hot water.
In this process, small volumes of water evaporate, lowering the temperature of the water circulating throughout the tower. The resulting colder water goes back to the equipment that absorbs heat or the condenser. This process happens over and over again to cool down heated equipment or condensers.
Parts of a Cooling Tower
Cooling towers vary in size and design, but they mostly contain the following parts. Note that cooling tower upgrades are available for these parts.
- Fan: the fan pulls cool air in through the filters located at the base of the tower. It then pushes the air to the top of the tower, taking heat and moisture with it.
- Driver Belt and Motor: these parts spin the fan blades.
- Drift Eliminator: this part changes the air’s direction while condensing some of the moisture in the leaving air. It helps reduce the tower’s overall operating costs.
- Condenser Water Inlet: the warm condenser water goes into the tower through this part.
- Spray Nozzles: the warm condenser water goes through these nozzles, causing it to split into a spray of droplets.
- Fill Packaging: the water droplets run down this part, increasing the surface area of the heat transfer. It allows air flowing from the opposite direction to carry some of the heat away, along with moisture from the evaporation.
- Filter: this is where the fan pulls air. It limits the amount of dirt entering the cooling tower.
- Condenser Water Outlet: the condenser water leaves the tower through this part.
- Makeup Water: a certain amount of water is held in the basin of the tower.
- Overflow: if the water level in the basin is too high, the excess water flows through this part and out to the drain.
- Drain: water is drained from the tower for maintenance and when the water impurities are too high.
Types of Cooling Towers
Classifying cooling towers can be a bit complicated since one tower may have multiple classifications depending on its functionality. However, they can be classified according to the following:
- Heat transfer method
- Airflow process
- Method of assembly
With these factors in mind, the following are the most common classifications of cooling towers you may find in the market:
- Wet cooling towers
- Fluid coolers
- Dry cooling towers
- Hybrid cooling towers
- Crossflow cooling towers
- Counterflow cooling towers
- Induced draft towers
- Forced draft towers
- Natural draft towers
- Fan-assisted natural draft towers
- Factory assembled towers
- Field-erected towers
No matter what type of cooling tower you use, this piece of equipment is a vital part of a heat and water management system. If a single component stops working properly, it can significantly reduce the efficiency of your overall cooling system.
Where are Cooling Towers Used?
Cooling towers are used to remove heat from buildings. You can usually find large towers in places like power plants, petroleum refineries, and other manufacturing facilities.
Smaller ones often sit on the rooftops of universities, hospitals, and shopping centers. The most common application of cooling towers, however, is inside an HVAC (heating, ventilating, and air conditioning) system, disposing of unwanted heat from chillers.
Because of their various applications and the range of industries that use them, cooling towers vary in size and design. Their overall structure depends on the cooling load of the building. The relative humidity of the air also determines the size and type of cooling tower a building needs.