Industrial atmospheric corrosion

Refineries, petrochemical plants, mining or other industrial environments contains large amounts of sulfur dioxide, carbon dioxide, nitrogen and other corrosive gases and dust, which is called the industrial atmosphere. Industrial air is dissolved in water vapor, and raindrops become "acid rain." These gases dissolved in condensation inside the plant and it become"self-produced acid rain", which will lead to corrosion of steel structures. Galvanized carbon steel screWS are corroded by acid rain, resulting in the water leakage of buildings.

Because of the ocean-atmosphere containing massive salt, there is a very active chlorine ions which are highly corrosive. Sea fog, chloride can corrode coastal steel buildings. Concrete has good corrosion resistance, but there is strong the chlorine ions penetration in the high chloride environment, which penetrating concrete covering layer lead to internal steel corrosion or even cracking concrete. The closer the building to the coast, the faster the steel structure corroded, and the corrosion rate is many times higer than in the inland industrial armoshere. Since the timber wetted produces acidoid, the steel conta cting with timber could also be severely corroded.

Electrochemical reaction usually refers that two kinds of heterogeneous metal or metal is enough to constitute a potential difference of the poles, in an electrolyte of the environment,constant loss of metal electron which causes corrosion phenomenon, called the electrochemical corrosion.