Case Study:

Holding Tank Rehabilitation

Situation:

A northern Indiana utility operates a biosolids treatment facility that includes a steel tank used for holding sludge during the treatment process. Over time, this tank had experienced significant deterioration due to constant exposure to corrosive materials and above-ground environmental factors. Seeking to restore the structural integrity and extend the service life of this critical asset, the utility turned to Conco Spray Solutions, a trusted Sprayroq Certified Partner, for a comprehensive rehabilitation solution.

Challenges:

Upon surface preparation, it was clear that the steel substrate was more severely corroded than anticipated. The deterioration was extensive, so much so that during vapor blasting with crushed glass media, holes were blasted through the steel walls in multiple areas. This necessitated immediate welding repairs, adding complexity to the project. Additionally, the open-top design and above-ground location of the tank meant it was subject to continuous environmental movement and exposure, requiring a flexible and highly robust lining system.

Results:

To meet the challenges presented by the harsh conditions and compromised substrate, Conco Spray Solutions employed a multi-step approach:

• Surface Preparation: Vapor blasting with crushed glass media was used to remove existing corrosion and prepare the steel surface.
• Structural Smoothing: A fast-set mortar was applied to round the sharp angles at the base of the tank, ensuring a uniform substrate profile.
• Priming: The cleaned surface was primed to optimize adhesion and enhance lining performance.
• Corrosion Lining: Sprayroq’s SprayShield Green was selected and applied at an enhanced thickness of 200 mils to offer superior corrosion resistance and flexibility. SpraySheild Green’s formulation is specifically designed to accommodate above-ground structural movement, making it ideal for the tank’s open-air environment.

Conclusion:

Despite the setbacks posed by the deteriorated steel, the project was successfully completed with a robust, monolithic lining system now protecting the tank from future corrosion. The SprayShield Green application not only restored the tank’s operational integrity but also provided long-term durability in one of the facility’s most aggressive environments. Thanks to the expertise of Conco Spray Solutions and the high-performance properties of SprayShield Green, the utility can expect reliable service from this rehabilitated asset for years to come.