Epoxy coatings for secondary containment of acids
Wherever harsh chemicals are stored, secondary containment infrastructure must be put in place and lined with suitable, protective coatings.
If a chemical spill was to occur, a well designed bund coated with a chemical-specific material should not only prevent corrosion of the bund wall, but also eliminate chemical leakage from the bunded area. This will protect the surrounding environment from contamination and provide overall safety on site.
Epoxy coatings are often the coating of choice when it comes to chemical bund protection, as they bond well to concrete and can be adapted to withstand the specific chemical being stored.
Epoxy coatings put to the test
An example of an epoxy coating application that withstood a harsh chemical spill was a spray-on novolac resin applied to a chemical bund at a water treatment plant located outside of Perth.
Hychem, formulators and manufacturers of a broad range of construction resins, were chosen to supply the coating to the bunded area.
A Materials Engineer on site said the Hychem TL9 HB coating suited the bund design and harsh chemical environment.
“In this case, the bund required a coating that was able to withstand the impact of Fluorosilicic acid (FSA) that was stored within the tanks on site. This particular acid is highly corrosive, therefore adequate protection of the concrete bund and the surrounding environment was crucial,” said the Materials Engineer.
According to Colin Murphy, Product Manager at Hychem, the TL9 HB formula was adapted specifically for FSA to ensure it would withstand the highly corrosive chemical if a spill was to occur.
“This ability to adapt our products to suit specific requirements is one of the unique benefits of the Hychem philosophy.
“We formulate and manufacture products in Australia, for Australian climate and conditions, and we often work with customers to tailor the formulas for their specific application.
“Our ability to adapt our products to suit specific requirements is one of the unique benefits of the Hychem philosophy,” said Mr Murphy.
The bund holds up
Hychem learned of a chemical spill at the water treatment plant when talking to the asset management team during a recent visit to the site.
“As part of our regular follow-up program to observe coating performance over time, we went back to the plant to inspect the condition of the coating.
“We learnt that a spill of FSA occurred during installation, but that the Hychem TL9 epoxy in the bund stood up to the harsh chemical with no sign of damage to the coating, even three years on.
“Many bunds are never tested in this way as the contingency they are designed for never eventuates.”
Why choose Hychem TL9?
Hychem TL9/E900 is a flexible, high impact epoxy coating with excellent resistance to a wide range of chemicals from concentrated sulphuric acid (98 per cent solution) to hydrocarbons, caustic solutions and aqueous salts.
Other benefits of the TL9 range include:
· Highly chemically resistant next generation novolac.
· Available as a thixotropic spray formula or can be roller applied.
· Film thickness from 150 microns to 3mm possible in one application.
· Can be used with Hychem E900, an elastomeric novolac binder that complements the TL9 range, to provide a heavy duty base layer. Proven performer in a range of very harsh acid environments.
· 100 percent success record in bunds.
· Long service life and warranty.
“At Hychem, we understand that the success of any coating system requires careful examination of all design and material criteria,” said Mr Murphy.
“Hychem offers technical assistance at design phase right through the lifespan of the product, working closely with design teams, consulting engineers, water authorities and project managers to ensure a high standard system is consistently applied.”