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The wastewater in petrochemical wastewater treatment projects is a corrosive medium with complex composition and variable conditions. In wastewater environments, in addition to the suspended solids from domestic wastewater, as well as nitrogen, phosphorus, potassium, and organic matter present in oils and fats, there are also acids, bases, salts, and various organic chemical compounds present in industrial wastewater. The corrosion of concrete structures and steel structural members by these chemical components is highly complex. The main characteristics of sewage corrosion are: ① water corrosion ； ②The types of corrosive media and their corrosivity are complex and variable ； ③The air has high humidity and a high concentration of chlorine particles, while harmful gases such as H2S and NH4 that escape from wastewater are also present in high concentrations ； ④Corrosion caused by various microorganisms and algae. In such a special environment, the requirements for corrosion protection of concrete tanks and steel structural components are stringent. Concrete tanks and channels not only require effective impermeability treatment but also the adoption of appropriate anti-corrosion measures ； The corrosion protection of steel structural components requires consideration not only of the corrosive effect of underwater electrolytes, but also of the strong autocatalytic effect of anions such as Cl–, S2–, NO3–, and SO42– on the corrosion of carbon steel. Additionally, it is necessary to take into account the erosion of these structural components by dissolved substances present in the steam generated when outdoor wastewater is heated; some poorly soluble particles may accumulate and adhere to the metal surface, leading to localized forms of corrosion such as underfilm corrosion, pitting, crevice corrosion, etc., which further accelerates the corrosion of the steel structures.