Oxygen is the first cause of corrosion. If oxygen dissolves in the feed water of this boiler, it causes the metal to oxidize. At temperatures above 60 degrees, the amount of corrosion increases. This type of corrosion is dangerous, and after a short period of time, the tank and pipes are perforated, this does not happen with the control of oxygen in the feed water. Carbonic gases are the second cause of corrosion. We all know that when this gas is dissolved in the feed water of the boiler, acidity occurs. With the separation of the acid produced in the water, hydrogen is removed.
The pH of the water decreases with the release of hydrogen ions. As the pH decreases, the water becomes acidic. If bicarbonate is present in the feed water, carbonic acid gas is created. Bicarbonate is converted into carbonate in the vicinity of the heat caused by burning and finally carbon dioxide is released. This carbonic gas along with water vapor covers all parts of the boiler. This gas is dissolved in water at very low temperatures and causes metal to rot and corrode. Also, the thickness of the walls of the tank and pipes decreases. Corrosion and rotting occur when the salt is hydrolyzed. Salts such as magnesium chloride are converted into hydrolysis due to proximity with the heat caused by burning. Hydrolysis of salt in feed water produces hydrochloric acid. The produced acids attack the surface of the metal and cause decay and rust.
What is needed to prevent the boiler from decaying?
At the very beginning of system startup, create a protective layer on the thermal surface of this boiler with the help of chemicals, implementing this method requires paying a lot of money. You can also prevent decay by choosing the metal carefully. Proper installation of hardener and correct treatment of the feed water of this boiler are other ways to prevent corrosion of this boiler.