Cooling Tower Basics Training

The cooling principle of the open cooling tower is that by spraying the circulating water on the glass fiber filler, through the contact between the water and the air, heat exchange is achieved, and then a fan drives the airflow in the tower to circulate, which will exchange water with water. The heated hot air is brought out to achieve cooling.

With this cooling method, the initial investment is relatively small, but the operating cost is high (water consumption, power consumption).

2. The cooling principle of the closed cooling tower is, in simple terms, there are two cycles: an inner cycle and an outer cycle. There is no filler, and the main core part is a copper tube surface cooler.

①Internal circulation: It is connected with the target equipment to form a closed circulation system (the circulation medium is soft water). Cool the target equipment and take the heat from the target equipment to the cooling unit.

②External circulation: In the cooling tower, it cools the cooling tower itself. It is not in contact with the internal circulating water, but only conducts heat exchange and heat dissipation through the copper tube surface cooler in the cooling tower. In this cooling mode, the operation of the motor is set according to the water temperature through automatic control.

Two cycles, in the case of high ambient temperature in spring and summer, two cycles need to run at the same time. The ambient temperature in autumn and winter is not high, and in most cases, only one internal circulation is required.

Closed cooling tower, or closed cooling tower, also known as closed cooling tower, referred to as closed tower.

The closed cooling tower is derived from the evaporative cooler, but it is actually a heat exchanger that combines the performance of a water-cooled cooler and a conventional cooling tower, and is also a heat exchange between the water cooler and the air cooler. Therefore, some manufacturers call it "evaporative air cooler". There are many forms of this type of cooling equipment. The common feature is that water is sprayed outside the partition heat exchanger and forced ventilation. The heat is transferred from the cooled fluid in the partition heat exchanger to the spray outside the wall through the wall. The spray water is then transferred to the air through forced convection between the spray water and the air, and the heat transfer from the spray water to the air is mainly composed of the latent heat of the evaporation of the spray water and the sensible heat exchange between the spray water and the air. Since the fluid to be cooled flows in a closed loop between the dividing wall heat exchanger and the external process equipment, in order to distinguish it from the general cooling tower in which the fluid to be cooled is in direct contact with the air, it is called "closed tower", and the corresponding The general cooling tower is called "open tower".

Performance comparison of open cooling tower and closed cooling tower

According to whether water and air are in direct contact:

①Open cooling tower;

②Closed cooling tower (also known as closed cooling tower, closed cooling tower).

  Compare:

①The cooling water of the open cooling tower is in direct contact with the air in the filler for heat exchange, so the cooling water system cannot be kept clean, and the cooling water will inevitably absorb dust and bacteria in the air.

②In the closed cooling tower, the cooling water flows in the coil, while the spray water and air are outside the coil, so the cooling water and the outside air are not in contact, which can keep the cooling water system clean forever.

  Advantage:

①It can keep the cooling water pure for a long time, eliminating the need to replace a large amount of cooling water. Furthermore, because it is a closed system, the evaporation of cooling water and the loss of drifting water are avoided, so that customers can save more operating water costs and are more suitable for use in areas where water resources are scarce.

②Due to the purity of the cooling water, the possibility of scaling and bacterial growth in the cooling water system is greatly reduced, the purification treatment of the water system and the cleaning of the pipes are reduced, and the customer saves a lot of daily maintenance costs.

③Because the cooling water is not in direct contact with the air, it will not pollute the cooling water and water system, so the closed cooling tower can work in places with harsh air environment, such as places with dust and peculiar smell.