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Corrosion-resistant materials for sewage tanks are classified into two categories based on their function: tank structure materials and anti-corrosion coatings/lining materials for the inner walls. Different materials are suitable for different levels of corrosion, allowing for selection according to specific needs. First, corrosion-resistant materials for tank structures: Sulfate-resistant silicate cement concrete features improved resistance to sulfate corrosion by limiting the content of tricalcium silicate and tricalcium aluminate; it is available in medium-resistant (P·MSR) and high-resistant (P·HSR) grades, making it suitable for sewage environments containing sulfates. Limitations: It can only resist low concentrations of sulfates; it is not resistant to strong acids or bases, and its ability to protect steel rebar is weak, requiring use in combination with an anti-corrosion lining. Applicable: Foundations for concrete tanks underground/underwater. Properties of the fiberglass reinforced plastic (FRP) monolithic tank: its density is only 1/4 that of steel; it can resist corrosion from most acids and bases in the pH range of 2–12; it can be prefabricated in modular units, allowing for fast construction and low weight. Limitations: Low mechanical strength; it softens at high temperatures (>60°C); UV protection is required when used outdoors. Applicable to: small industrial sewage tanks, buried integrated treatment equipment. Features of the 304/316L stainless steel monolithic tank: high structural strength, resistance to high and low temperatures, a service life of 15–20 years, easy cleaning and maintenance; 316L contains molybdenum, giving it 3–5 times greater resistance to chloride corrosion compared to 304. Limitations: High cost, pitting is likely to occur at the weld points, and additional protection is still required in strong acid environments. Applicable: high-demand wastewater treatment units, coastal or high-salinity wastewater scenarios. II. Corrosion-resistant materials for inner wall protection (core protection of concrete tanks): Characteristics of epoxy resin fiberglass lining: adhesion ≥ 3 MPa, excellent alkali resistance, mature manufacturing process, low shrinkage rate, and moderate cost – making it suitable for most common corrosion conditions. Limitations: It has poor resistance to strong acids, its tolerance to high temperatures does not exceed 80°C, and it is not suitable for use in hydrofluoric acid environments. Applicable to municipal sewage, domestic sewage, and ordinary industrial wastewater tanks; generally, the \"three layers of fabric and five layers of coating\" treatment method is used, with a total thickness of 2.5–3 mm. Properties of vinyl ester resin fiberglass/glass flake mortar: resistant to strong acids (pH 1-13); after being immersed in 40% sulfuric acid for 30 days, it retains over 85% of its strength. Its resistance to penetration is far superior to that of ordinary fiberglass, making it the ideal choice for highly corrosive environments. Limitations: High cost, strict requirements for construction techniques, and precise control of the curing agent ratio is necessary. Applicable to: chemical wastewater, industrial wastewater ponds containing high concentrations of hydrogen sulfide, as well as those with strong acids and bases. Properties of acid-resistant bricks: Made of silica, they possess excellent corrosion resistance, a long service life, and are capable of withstanding high-concentration acidic environments. Limitations: The construction is complex, requiring use of epoxy putty for bonding, and the initial investment cost is high. Applicable to: high-acidity chemical wastewater tanks, and strong-acid environments with prolonged exposure. Properties of two-component potting silicone rubber: strong resistance to permeation, tolerance to soil stress corrosion, suitable for underground or underwater structures. Limitations: Not suitable for benzene-based solvents and drinking water tanks. Applicable: Severe corrosion environments such as petrochemical underground sewage tanks.