boiler ceramics energy conservation Anticorrosive coating
Industrial boiler is one of the important equipment in industrial production activities. As the equipment that provides heat and steam, it can be used for power generation in power plants, heat supply in steel plants and district heating. But the water wall, reheater, superheater and other high temperatures Heat exchanger During the working process, due to the existence of oxygen in the air and corrosive impurities such as sulfide, nitride, chloride ion, fluoride ion, etc. produced by fuel combustion, the oxidation, corrosion, and coking of boiler tubes will lead to problems such as lower heat exchange efficiency, shorter service life of equipment, and more importantly, boiler shutdown.
Corrosion causes of boiler tubes:
(1) High temperature oxidation corrosion: metal in nature will react with oxygen and water in the air to generate metal oxides and hydroxides. However, in the boiler, the high temperature released by fuel combustion will accelerate this process, leading to oxygen corrosion of boiler tubes in a very short time;
(2) Gaseous corrosion of high-temperature acidic substances: because the fuel contains sulfur, chlorine, fluorine and other substances, the substances generated after combustion will react with metal oxides to generate low melting point metal * * * salts, metal chlorides or metal fluorides, etc. Generally, these metal salts will volatilize at a high temperature of>500 ℃, leading to the exposure of subsequent metal layers, thus causing corrosion cycles;
(3) Corrosion of liquid condensation acid: the presence of sulfide in the flue gas will increase the dew point temperature of the flue gas. Generally, when the flue gas temperature is less than 200 ℃, the condensation acid will gradually form, leading to corrosion of the metal wall.
For the corrosion of boiler tubes, it is necessary to select appropriate metal protection coating ZS-1021 high temperature sealing coating of Zhisheng Weihua has high temperature resistance and can be used for boiler water wall, heat exchanger and other parts to prevent high temperature oxidation corrosion, extend equipment service life and simplify construction.
