The method and necessity of deoxidization of boiler water supply
Industrial boiler is an indispensable equipment in daily industrial production, however the oxygen corrosion of industrial boiler is also the most common. The main reason is that a large number of oxygen molecules are contained in the water supply of the boiler. After leaving the environment such as oxygen molecules and water，The steel components in the boiler will undergo oxidation reaction, which will corrode the body of the boiler. So that the deoxidization of the boiler water supply is a very important thing.
The oxygen corrosion is usually started from small range of ulcerative corrosion and local corrosion, but the effect of this corrosion on the strength of metal components is very serious. In recent years, reference for the damage of boiler components and boiler accidents and scrapping cases, the damage caused by excessive oxygen content in boiler water supply, accounting for the lion's share of the market. Due to factors such as the deoxidation of boiler feed water, the damage caused by factors such as dehydration is also increasing.So that the government has made the standard regulation for the related boiler, the boiler with rated evaporation 2 tons/h or more, the deoxidization measures must be used,and the oxygen content in the water is controlled in the scope of the compliance according to the difference of pressure and volume. At present, there are two main methods for boiler water deoxidation.
The advantages of thermal deoxidization are as following:
1. While removing oxygen from water, thermal deoxidization can also remove harmful gases such as CO2, H2S and NH3 to protect the boiler from erosion.
2, the effect of thermal deoxidization is relatively stable. After deoxidization, oxygen molecules in water can be reduced to less than 0.01mg/L, which can effectively remove oxygen molecules in water and promote the decomposition of bicarbonate in water, thus reducing the total amount of salt and compounds in water.
3, it will not destroy the water quality.
What is the principle of thermal deaeration?
First of all, as we known, the components of the daily atmosphere are mostly nitrogen, oxygen, and the rest are carbon dioxide, water vapor, and rare gases. we call atmospheric pressure is the sum of the total pressure of these mixed gases. According to the rule of dissolved gas, the solubility of any gas in the water is proportional to the pressure of the gas, that is to say, the greater the pressure, the larger the amount of water dissolved and the smaller the opposite. Therefore, when the water is boiled to a boiling point, the oxygen content in the water is close to zero, and the dissolved oxygen is rapidly released from the water. This is also the basic principle of thermal deoxidization.