Problems with the protection of the circulating water system?
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Affected by the economic crisis, the facility has to shut down; it is estimated that this shutdown will last around a month. How should the recirculating water system be managed? Drain the water completely? Does the system stop when it’s filled with water? Should we run one pump in the recirculation water system for low-load circulation?
I haven’t encountered this issue in practice; it would be better to empty the entire system and clean it as well as apply a protective coating before starting it up again.
The circulating water system is used to drain the water, the pool is dug out, and the system is cleaned thoroughly. But I’m not sure what company you work for – is it still frozen there?
It is best to drain the water from the circulating water system, and then use dry hot air to purge the pipes!
There are two options for you to choose from: 1. Emptying option: This approach requires the system to be cleaned and coated before water can be removed from it. The reason is that corrosion in pipes and similar components occurs at a much lower rate when there is water present, as compared to when they are completely exposed to air; therefore, cleaning and applying protective measures are necessary before emptying the system. This approach is quite commonly used, as it is inevitable that scaling and corrosion will occur after the system has been in operation for some time; it’s great to be able to use this period to carry out maintenance and improvements on the system. 2. Full-water filling scheme: This scheme is suitable when corrosion and scaling in the original system are not severe, and the system is well protected during normal operation; therefore, it is possible to fill it with water. In fact, filling it with water serves as a form of protection for the system. If the equipment contains water on one half and air on the other, corrosion will increase due to the creation of a potential difference.
Three options: First, after stopping the system, drain all the water from it and fill it with nitrogen (provided that your valves can be closed properly). Second, before stopping the system, increase the concentration of corrosion inhibitors in the circulating water to 2-3 times the normal level, then seal the circulating water within the equipment and pipelines before shutting down the pumps. III. Keep one pump running at low flow rate, with chemicals being added as normal ； Based on our company’s many years of operational experience, Option 3 is a good and cost-effective method.
When our company stops production, the entire recirculation water system is filled with water; make sure to run the pumps regularly
Our company adopts a circulating water system that continues to operate without stopping, even when the load decreases; this prevents pipe corrosion, and there is no need for pre-coating during startup.
During the major maintenance of our facility, a circulating water system was used to keep the area filled with water at a low flow rate; this approach was recommended by the water treatment company.
A cost-effective approach is to add an appropriate amount of corrosion and scale inhibitor, and to start the pump circulation regularly (at least once a week) for a certain period of time (4–8 hours); this will result in minimal corrosion of the system
It is recommended to use a pump with a low flow rate to maintain the operation of the circulating water system. It’s rather troublesome to deal with it when stopping completely for a long time and then starting the vehicle again. Moreover, the corrosion of the equipment is difficult to control.