The sewage treatment plant (STP) is a "nightmare factory" for building materials. The primary threat here is hydrogen sulfide (H₂S) gas produced by anaerobic bacteria. When hydrogen sulfide dissolves in moisture on the surface of concrete or steel structures, it is oxidized into sulfuric acid, causing severe "microbially induced corrosion" (MIC). Ordinary industrial paints simply cannot survive in such an environment. PZSSS provides specially developed specialty coating systems designed to neutralize these invisible threats.
1. The Challenge of the "Waterline Zone"
In sedimentation tanks and clarifiers, the most severe corrosion occurs near the waterline (splash zone). This area experiences continuous wet-dry alternation accompanied by the accumulation of high concentrations of hydrogen sulfide.
- PZSSS Solution: We recommend the use of a glass flake epoxy system. The overlapping glass flakes form a "maze-like" path, making it nearly impossible for acidic molecules to penetrate the coating and reach the substrate.
2. Protection of Concrete Structures
Corrosion protection is not limited to steel. Concrete structures in wastewater treatment plants often suffer from "concrete powdering" due to acid corrosion.
- PZSSS Solution: Our solvent-free, high-film-build epoxy lining is designed to seal concrete capillary pores, providing a smooth and easy-to-clean surface that effectively resists biofilm and acidic condensate in anaerobic tanks.
3. Long-term Maintenance Strategy
Since the cost of shutting down a wastewater treatment plant for maintenance and inspection is extremely high, durability is the top priority.
- Chemical resistance: Our coatings are specifically tested to resist common chemicals used in wastewater, including chlorine, lime, and various polymers.
- Surface treatment: In such environments, high-pressure water jet or sandblasting must be used before painting to thoroughly remove salts embedded in the substrate, followed by application of PZSSS High-Adhesion Primer.
