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Taking into account the previous background on corrosion caused by acidic sulfate wastewater, the most suitable materials are recommended for different sulfate concentration ranges: 1. For low concentrations (≤1500 mg/L, in ordinary municipal or lightly polluted environments), the preferred material is ordinary Portland cement supplemented with concrete anti-sulfate corrosion inhibitors. Advantages include low cost and ease of application; it can be used in conventional concrete projects to meet the long-term corrosion resistance requirements in civil and ordinary wastewater discharge applications. 2. Medium concentration (1500–10,000 mg/L, in industrial wastewater scenarios): Preferred materials are sulfate-resistant silicate cement plus a vinyl ester anti-corrosion coating. Advantages: it offers both structural strength and corrosion resistance, enabling it to withstand the long-term erosion of most industrial acidic sulfate wastewaters, with an excellent cost-performance ratio. 3. High concentration (>10,000 mg/L, in highly corrosive chemical environments): Preferred materials include N08020 (Alloy 20) metal materials, as well as acid-resistant cement linings and acid-resistant bricks. Advantages: They can withstand high-concentration, strongly acidic sulfate media; their corrosion rate is much lower than that of ordinary stainless steel, making them suitable for use in chemical reactors, tanks for storing high-concentration waste liquids, and other extreme operating conditions. 4. For general applications across all concentration levels: Preferred materials are high-silicon cast iron/fluoroplastic alloys. Advantages: They can handle acidic sulfate environments with various concentrations and wide temperature ranges, offering stable performance; thus they represent a reliable choice for scenarios with complex operating conditions and large concentration fluctuations.