Stopping of the cooling circuit
It is possible that from an eventual situation, such as slowdown in production, a need to pause the cooling towers arises.
TORRAVAL recommends the following actions in order to proceed to stop the cooling circuit, for open circuit towers:
- OPTION 1: Maintaining the water flow
When stopping the cooling tower, regardless of whether the process needs to be cooled and whenever possible, it is recommended to keep the water flow in the cooling system, stopping the fans, and maintaining the chemical dosage, as well as the purge and make-up flow.
This option minimizes future incidences when restarting. The system restart should be made as follows:
- Checking free movement of the fans
- If available, checking the oil level in the gearbox
- Starting the fans
- Starting the process to be cooled
- OPTION 2: Stopping the water flow
If option 1 is not possible when stopping the cooling tower, likely it is recommended to empty the cooling tower basin, and the complete cooling circuit when workable. Restarting the system proceeds as follows:
- For cooling towers stopped longer than 4 weeks, the unit must be cleaned, according to the legionella control regulations RD 865/2003
- If the cooling tower has been previously emptied, the system will be filled
- Cooling water pumping will be started
- For cooling towers stopped longer than 2 weeks, a chemical shock disinfection will be carried out, by adding chemical additives, according to the legionella control regulations RD 865/2003
- Checking free movement of the fans
- Checking the oil level in the gearbox when available
- Starting the fans
- Restart the process to be cooled