What Is a Cooling Tower?
A cooling tower is a device used to cool a certain fluid. The target fluid can be exhaust gas, process water, circulating water, etc. The most commonly used type of cooling tower is the cooling tower for circulating water. The most commonly used type of cooling tower is for cooling circulating water, which is widely used because of its simple structure.
Cooling towers range in size from relatively small ones used for air conditioning to huge ones as large as a skyscraper used for cooling an entire plant.
When cooling water is cooled by a cooling tower, there is a risk of bacteria growing in the circulating water, which can be harmful to human health, so additives are generally injected to control water quality.
Uses of Cooling Towers
Cooling towers are used in various aspects.
In everyday life, they are used for air conditioning in large commercial facilities and for freezers in large warehouses. As the size and capacity of cooling systems increase, cooling towers are used.
In industrial applications, cooling towers are used to cool the inlet air of gas turbines in power plants and to cool exhaust gases in process plants. In industrial applications, cooling towers are used when it is more rational to cool an object, and the recovered heat is often reused from the viewpoint of energy conservation. The most commonly used heat transfer medium is tap water.
Principle of Cooling Towers
Cooling towers are a type of heat exchanger. In principle, the cooling object is cooled by exchanging heat through the application of air to the circulating cooling object.
Cooling towers can be broadly divided into two types: open type and closed type.
In the open type, heat is extracted by direct contact with the cooling target with the outside air inside the cooling towers. This type is used when the cooling target is a harmless liquid.
The open type is often used for cooling circulating water and consists of a water storage tank, circulation pump, water supply unit, and chemical injection unit, and has the following structure: Water in the water storage tank is circulated by the circulation pump and constantly introduced into the cooling towers. In the cooling towers, the water is heated by the atmosphere to keep the temperature in the storage tank at a constant low level. Since water evaporates little by little in the cooling towers, the water level in the storage tank is kept constant by the water supply system. Bacteria can grow in water storage tanks due to prolonged circulation, so the water is sterilized by a chemical injection system. The same mechanism is used for cooling towers that do not circulate drinking water.
In enclosed cooling towers, the cooling target is cooled by indirect exposure to the atmosphere through conduit coils or other means. Enclosed cooling towers are used when it is not desired to open the cooling object to the atmosphere.