Understanding and selecting coating options for wastewater treatment vessels is essential to extending the lifespan of tanks, pipes, and other equipment while also ensuring their structural integrity.
Specialized coating systems provide a necessary barrier that protects against the harsh chemicals such as sulfuric acid, sodium sulfates, ammonium, and moisture penetration that are highly corrosive and often found in wastewater treatment facilities.
Some of the most common and effective coatings are;
- Epoxy coatings are highly resistant to chemical corrosion and provide excellent protection against corrosion. Epoxy coatings are very common due to the fact they are very durable and highly tolerant of acids and alkaline substances. For potable water, NSF 31 is often used.
- Polyurethane coatings are extremely popular because they can be applied as a topcoat to epoxy coverings and provide additional corrosive resistance as well as UV protection making it an ideal option for external tank surfaces. Polyurea coatings are also incredibly durable and can last up to 25 years or more with proper installation and routine maintenance.
- Vinyl ester coatings are also well known for their resistance to harsh chemicals including strong acids and bases. This is a durable coating solution for aggressive wastewater protection.
- Fiberglass Reinforced Plastic or (FRP) are also suitable for many wastewater applications due to the fact that it is a composite material that combines fiberglass with a resin matrix and does not require additional coatings.
- Glass-Fused-to-Steel (GFS) Coatings are created by fusing a glass coating to the steel substrate at high temperatures providing excellent corrosion resistance.
- Rubber Linings, such a natural rubber or synthetic elastomers like neoprene can provide protection against chemical attack and abrasion making them great options for hostile wastewater.
- High-Density Polyethylene (HDPE) Liners are used to protect concrete or steel structures and offer extreme hardiness against a wide range of chemicals. This is a great option for lining containment structures and wastewater ponds.
- Cementitious Coatings are applied as a thick protective layer that holds up well against acids and abrasion. These coatings are most often used in the rehabilitation of concrete wastewater structures.
- Teflon (PTFE) Coatings offer exceptional non-stick properties and are most often used in applications such as in filter plates and pumps.
What coating do you choose?
Ultimately the choice of coating will depend on factors such as the chemicals most found in the wastewater, temperature and environmental conditions and the type of vessel being safeguarded. It’s essential to consult with coating specialists and engineers to determine the most suitable and enduring option for your vessels. Proper surface preparation an application technique ensure resilience and cost effectiveness. Additionally, investing in the ongoing maintenance of these coatings with regular inspections, cleaning, repairs and recoating will increase the life expectancy and durability of your equipment.
Learn more
Rexarc is an expert manufacturer and designer of custom pressure vessels in carbon and stainless steel. If you have questions about pressure vessels, would be interested in a custom vessel quote or to learn more and how they can be used in water treatment, we’d be happy to chat with you!