Chemical cleaning of boiler can be divided into the following steps

1. Water pressure leak detection:

Water pressure leak detection is to fill the system with water by water pump to check whether there is leakage point in the system. If the system is in good condition, it can be ready for the next work.

2. Chemical cleaning:

Mix the cleaning agent with water to reach the concentration (less than 10% according to the national regulations), and then use the pump to circulate the solution into the system, and continuously drain the water to avoid air resistance. Continue to supplement the cleaning solution until the water outlet discharges the cleaning solution, and then continue to use the pump to circulate for 10-20 hours (depending on the reaction situation, appropriately extend or shorten the reaction time).

3. Water cleaning:

The purpose of water flushing is to clean the residual cleaning solution in the system, so as to avoid local corrosion of the system. Test the water outlet with pH test paper until it is neutral.

4. Passivation:

Passivation reaction is to form a passivation film on the surface of the activated metal after cleaning, so as to avoid oxidation reaction in contact with oxygen or free oxygen in water. The ratio of passivator and water is 3%, and then it is pumped into the system. After the system is filled with passivator, the reaction time is 10-24 hours, and then the passivation solution is discharged and ready for water flushing.

5. Water flushing:

The purpose of this water flushing is to clean up the residual passivation solution, so that the decomposed and stripped dirt in the system can be discharged with water, and the pH value of the test is neutral, which is the end point of cleaning.