Antifreeze for closed cooling tower
Author：Trlon Views: Time:2020-10-22
In some areas, the temperature in winter is usually below zero, and the operation of closed cooling towers has become increasingly prominent. If it is not solved well, the heat exchange tubes or other parts of the cooling tower may be damaged by freezing. According to different process characteristics, some closed cooling towers run all day in winter, some run partly, and some are almost not used. But all need to consider the issue of antifreeze.
1. Anti-freezing measures for occasions that are basically not used in winter
If the closed cooling tower does not need to be operated in winter, the spray water and internal circulating water must be drained when shutting down. It is recommended that the internal circulating water be forced to be emptied by compressed air, and the carbon steel pipe heat exchanger is not recommended to be emptied to prevent freezing.
2. Anti-freezing problem in some operating occasions
The antifreeze of a closed cooling tower has two parts: the spray water system and the internal circulating water system (softened water).
The antifreeze problem of the spray water system is usually to add an electric heater in the water pool. Generally, the spray water is turned on when the spray water is lower than 5℃, and it is stopped when the spray water is above 8℃. The temperature probe transmits the signal to the control cabinet to automatically control the start and stop of the electric heater. The power selection of the electric heater is determined according to the circulating water volume and the outside air temperature.
The antifreeze of the internal circulating water system can be added with glycol solution or electric heating equipment. The freezing point temperature of the glycol solution should be selected below the local minimum temperature.
For larger cooling system occasions, you can consider digging a pool to put spray water into it, which can save electricity costs due to electric heating operation, and you can also put medicine in the pool to improve the quality of spray water.
3. Anti-freezing problem in occasions of year-round operation
For closed cooling towers that operate all year round, if equipped with an electronic control system, the number of cooling towers may change due to changes in the load of the main system. Therefore, it is also necessary to consider the issue of antifreeze. Unused equipment can be emptied before winter to prevent freezing.
With the continuous development of science and technology, closed cooling towers will inevitably usher in greater development and application space.