Cooling Tower

What is a cooling tower ?
They are the heat rejection devices used to transfer process waste heat to the atmosphere. They may either use the evaporation of water to reject process heat . They help in cooling the working fluid near air temperature. Its common applications include cooling the circulating water used in oil refineries, chemical plants, power plants and building cooling. They are classified by use into two categories :

• HVAC (air - conditioning): It is a sub category of cooling tower rejecting heat from a chiller. Water-cooled chillers are more energy efficient than air-cooled chillers due to heat rejection to tower water at near wet-bulb temperatures.
  
  
• Industrial : They are much larger than HVAC tower. They are used to reject heat from various sources such as machinery or heated process material. The main use of them is to remove the heat absorbed in the circulating cooling water systems used in power plants, petroleum refineries, petrochemical plants, natural gas processing plants, food processing plants, semi-conductor plants, and other industrial facilities.

Malfunction of Cooling Tower:
When due to any fault or failure some amount of water goes to the top of cooling tower then it causes tower to freeze. If a cooling tower is allowed to freeze and build up ice then the ice can grow to massive sizes and can result in the tower falling through the roof. To besiege from freezing , a basin heater is installed , air flow through the tower is reduced and in some cases where evaporative closed loop towers are used the tower spray water is drained completely.

Cooling Towers Spares :
Cooling towers uses high quality spares like :

• PVC Fills
• Rotary Sprinkler
• FRP Casing
• Fan Assembly

Classification of Cooling Towers
There are various types of cooling towers which can be categorized as follows:

• By Sizes and shapes: Cooling towers are available in all kinds of shapes and sizes. The popular ones are the huge, hourglass or bottle shaped constructions, often found at power stations.
  
  
• By Material: The walls of the cooling towers are made of concrete. Cooling towers are also constructed plastic, wood, and metal. Concrete-wood-plastic combinations are also possible.
  
  
• By One or more cells: Sometimes, cooling towers consist of several cells, where each cell is able to operate independently. In such cases, each cell has its own fan.
  
  
• By construction: The cooling towers can be field-erected or factory assembled.
  
  
• By method of heat transfer: Cooling Towers can be wet cooling tower or dry cooling tower.
  
  
  
• By Air flow: This can classify cooling towers into
  • Mechanical draft cooling tower
  • Forced draft coolingtower
  • Induced draft cooling tower
  • Nature draft cooling tower
  • Fan assisted nature draft cooling tower
  
  
  
• By Air-to-water flow: This type of cooling towers can be classified into counterflow, cross flow and spray-filled cooling towers.