Wastewater treatment plants are some of the most corrosion-prone facilities in the industry. This is an unavoidable consequence of the natural function of wastewater treatment plants, which is to process sewage water to free it from pollutants.
Storage tanks and containers, in particular, withstand the worst of corrosion coming mostly from the chemicals and decontaminating materials used in treating sewage water. Most of these chemicals are corrosive agents that attack the tank’s lining or coating system. Some non-corrosive chemicals, reacting with other elements in the water, air or other chemicals, may even contribute to corrosion indirectly.
It therefore takes a special kind of anti corrosive coatings to provide long-term protection against these harsh corrosive elements.
Before the painting contractor can specify the correct anti corrosive coatings system for the wastewater treatment tank, it is advisable to understand the common sources of corrosion plaguing wastewater tanks. As already mentioned, certain chemical and biological materials used to treat sewage are major corrosive agents. Extreme changes in temperature, also contribute to structural degradation. Again, the anti corrosive coatings appropriate for freezing, thawing, and extreme temperatures should be chosen during repair and maintenance work.
The steady flow of sewage water may carry rocks, silt, or other solid materials that can cause erosion and abrasion in the inner tank lining, and through time, may cause a lining failure. Anti corrosive coatings that are resistant to wear and tear should also be considered.