Water clarifier (Accelator) steel restoration and coating with MCOR 1161

The City of Pompano Beach consulted with MCOR and MCOR certified contractor Select Environmental Services to come up with a solution to repair its water treatment plant’s Accelator Clarifier. The severity of the corrosion on the steel led to the question of if the water clarifier could be repaired or if it would have to be replaced.

After a careful consideration of time, budget, and products, the City of Pompano Beach and MCOR concluded that the Accelator Clarifier could be repaired to its original state or better.

MCOR helped the engineers design the system and specifications for steel repairs and coating for the potable Accelator Water Clarifier. These specifications were designed for the steel coating per SSPC and NACE standards. After the specifications were completed, the next step in the process was to select a contractor to perform the work. MCOR has a network of certified contractors that are also SSPC and NACE certified and that can bid on coating and rehab projects, which allows us to ensure quality control and serve the warranty without having to inspect the project on a constant basis. This also allowed the City of Pompano Beach to go about its daily business and let MCOR manage the project which is another service provided if requested.

The City of Pompano Beach utilized an active annual, itemized contract that allowed it to price the project per square foot. This process saved time and streamlined the start date, pushing it up to prevent any further deterioration to the steel structure and avoid the spring rainy season.

The Accelator Clarifier uses turbulence by a rotor-impeller and chemicals to treat the water, allowing the separation of sludge and contaminants from the water. This process takes a massive toll on the steel structure, eventually causing it to need a high-performance coating that can handle this environment and combat ultraviolet (UV) rays, which damage coatings exposed to outdoor environments.

Exposed lime and calcium build-up when drained.

Near white metal abrasive blasting.

Holding primer with MCOR Primecoat mTE.

After dry abrasive blasting in accordance with SSPC-SP 10/NACE No. 2 “Near White Blast Cleaning,” MCOR inspected the surface as part of its agreement with city, and the patching and re-building process began. The surface preparation crew did a terrific job getting the steel to where it needed to be so it could be properly rehabbed and coated.

A flash-rust holding primer was used because of the high humidity in South Florida. The choice product applied was the MCOR Primecoat MTe.

Because the steel had many holes at the weld seams, MCOR suggested the use of its structural-grade polymer repair material, MCOR 3115 | mClad mFill, to patch and reinforce the welds and seams, fill any holes, and re-build any areas that may have weakened from the corrosion.

Structural-grade polymer repair at welds and seams with MCOR 3115.

Structural-grade polymer repair at welds and seams with MCOR 3115.


Once all the steel was repaired and primed, MCOR conducted another inspection for the city to determine the final acceptance of steel prep prior to the coating system. Once the steel structure was deemed suitable, the coating had to be installed to prevent future corrosion and assist in buildup of lime and calcium.

Corrosion is inevitable in these environments, and it is crucial to pick the right coating for the right environment. MCOR 1161 | mCoat IM 61 was determined to be the best solution for this application.

MCOR 1161 is a urethane-modified-epoxy (UME) that has great chemical and abrasion resistance for a coating, and it is well suited in this type of clarifier because it also has great UV tolerance and build-up resistance due to its urethane finish.

It is also a 1:1 mix ratio, and it can be applied with spray, brushes or rollers. This allows applicators to choose the best way to apply it after considering all the logistics of their environment. On this project, all three methods were utilized.



First coat of the MCOR 1161, sprayed on at 0.5mm (20 mils) DFT.


The top coating system consists of two 0.5mm (20 mils) coats for a total of 1mm (40 mils) DFT. Once complete, the steel structure is protected and restored to profile

The MCOR 1161 coating system is approved for potable drinking water environments to ANSI/ NSF-61 standards.

The first coat was applied by spray.  Touch-ups and further strip coatings at the seams were done with a brush. The first coat cured for 24 hours, and the next day the second coat was applied to finish the system.

The system was completed, and a holiday test was conducted. With the use of the MCOR 3115 at the welds and seams, strip coating, and the two-coat system, less than 1% of the surface needed last-minute touch-ups. The system was returned to service after 48 hours of curing.




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For more information on MCOR 1161 | mCoat IM 61, visit mcor.net/mcor-product/mcor-1161-mcoat-im-61/
For more information on MCOR 3115 | mClad mFill, visit mcor.net/mcor-product/mcor-3115-mclad-mfill/
For more information on MCOR Primecoat MTe, visit mcor.net/mcor-product/mcor-primecoat-mte/
To learn more about MCOR’s complete product line, visit mcor.net/products


City of Pompano Beach, Utilities Department- Water Treatment Plant
Structural metal repairs (MCOR 3115)
Metal holding primer (MCOR Primecoat MTe)
NSF/ANSI 61 Certified, Spray Applied, Urethane Modified Epoxy Coating  (MCOR 1161)
MCOR Certified Contractor – Select Environmental Services