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Corrosion of industrial wastewater tanks is the result of the combined action of physical, chemical, and microbial factors; it is necessary to select appropriate protection measures based on the mechanisms of corrosion in order to effectively extend the service life of the tanks. I. Common causes of corrosion: Industrial wastewater tanks are usually made of reinforced concrete, and corrosion results from the combined effect of multiple factors. Physical corrosion: Freeze-thaw cycles and dry-wet cycles cause the concrete to expand and contract repeatedly, leading to gradual cracking and peeling ； The long-term scouring by water currents carrying sediment can also wear away the surface layer of concrete. Chemical corrosion: Acids, bases, sulfates, chloride ions, and other substances present in industrial wastewater can damage the structure of concrete as well as the passivation layer surrounding steel rebar. For example, strong acids can neutralize the alkaline components in concrete, while chloride ions can trigger electrochemical corrosion, causing the steel rebar to rust and expand, thereby cracking the concrete cover. Microbial corrosion: Sulfate-reducing bacteria in wastewater produce hydrogen sulfide, which is then oxidized to sulfuric acid; this process continuously corrodes concrete, ultimately leading to cracks and deterioration of the structure. II. Mainstream protection solutions: The current industry standard for anti-corrosion treatment follows the \"Code for Anti-Corrosion Design of Industrial Buildings.\" The appropriate treatment method is selected based on the level of corrosion. 1. Glass fiber reinforced plastic lining (the most commonly used method), which involves the use of \"one layer of fabric with three coats of resin/two layers of fabric with four coats of resin/three layers of fabric with five coats of resin.\" Here, \"fabric\" refers to glass fiber cloth, while \"resin\" refers to anti-corrosion resins. Suitable applications: Ordinary industrial wastewater tanks handling acids and bases; for acidic environments, the three-layer-with-five-coats method is preferred, while for ordinary tanks, the one-layer-with-three-coats method is sufficient. Material selection: Epoxy resin is the most widely used, with low shrinkage and reasonable cost ； For high-corrosion environments, epoxy vinyl ester resins are recommended, as they offer better corrosion resistance, but at a higher cost. Core requirement: The concrete base layer must be cured for 28 days and have a certain moisture content