Long-Term Corrosion Protection for Industrial Tanks

Mine tanks, located in King Island, VIC, are an essential component in the mining process and are used for the storage and processing of tungsten, a metal that is used in a variety of industrial applications. However, the harsh operating environment of the mine means that the tanks are constantly exposed to corrosive elements, which can lead to significant damage and downtime if not properly protected.

To address this issue Dulux® Protective Coatings Trade Specialist, Rob Esposito recommended a two-part approach to protect the tanks from corrosion: an internal liner for immersion service and a three-coat zinc-rich coating system for the exterior.

Challenges of Corrosion in Harsh Environments

The first step in the process was to prepare the surface of the tanks for coating. This involved a thorough cleaning and dry abrasive blasting in accordance with AS1627.4 Class 3. This ensures that the surface is free of any contaminants that could compromise the adhesion of the coatings.

Internal Liner and Three-Coat Zinc-Rich Coating System

“For the internal lining, we recommended a chemically resistant phenolic epoxy liner, stating that this type of coating is specifically designed for immersion service and makes it an ideal solution for the tanks.” explains Rob Esposito. The system used on the internal surfaces of the tanks consisted of two coats of Dulux® Durekem® MPP, each applied at 250-microns (µm) DFT.

Durekem MPP is a high-performance two-component epoxy coating system with excellent adhesion, abrasion and chemical resistance properties. It can be used on various surfaces, including concrete and steel, and is ideal for harsh environments like chemical plants and oil refineries.

For the exterior of the tanks, a three-coat zinc-rich coating system was recommended to provide long-term corrosion protection. This system is designed for harsh or marine environments and is compliant with AS/NZS 2312.1:2014 Category C5-M (very high marine corrosivity). The system used on the exterior of the tanks consisted of three coats:

• 1st coat: Dulux® Zincanode® 402, applied at 75-microns (µm) DFT
• 2nd coat: Dulux® Duremax® GPE, applied at 150-microns (µm) DFT
• Topcoat: Dulux® Weathermax® HBR, applied at 75-microns (µm) DFT

Benefits of Corrosion Protection

By using this three-coat system, the tanks are protected from the elements that can cause corrosion, including saltwater, moisture, and UV radiation. This helps to extend the life of the tanks and reduces the need for costly repairs and downtime.

This project is an excellent example of the importance of corrosion protection in harsh operating environments. By working with an experienced applicator and using high-quality coatings from Dulux Protective Coatings, we were able to ensure that their tanks are protected from corrosion and can continue to operate efficiently.