How to choose the cleaning agents for industrial boilers

For different scales and metal materials, suitable pickling agents and co-solvents should be selected. The cleaning agents for industrial boilers are generally selected as follows:

(1) Hydrochloric acid is generally used to clean carbonate scale.

(2) Silicate scale can be cleaned by adding hydrofluoric acid or fluoride to hydrochloric acid.

(3) Sulfate scale or scale mixed with sulfate and silicate should be boiled with alkali in advance, and then washed with hydrochloric acid or fluorinated hydrochloric acid.

(4) Iron oxide scale can be cleaned by adding fluoride to hydrochloric acid or nitric acid.

(5) For power station boilers, when the copper content in the primary oxide scale is high (CuO>5×10-2), measures should be taken to prevent copper plating on the metal surface. Generally, cleaning aids such as hydrochloric acid, fluoride, and thiourea can be used. .

(6) When cleaning austenitic steel, hydrochloric acid should not be used as a cleaning agent. Generally, organic mixed acids such as hydrofluoric acid, EDTA, citric acid, formic acid, and acetic acid can be used as cleaning agents to clean boiler parts containing chromium materials.