Coating Trials Led Plant Manager To Specify Polyurea
Tom Steinbach understands the value of an education. Steinbach is the facility manager at a 4.0-mgd wastewater treatment plant in Oconomowoc,Wis. Back in the late 1990s, he looked at areas of slowly degrading concrete in the plant and foresaw some major coatings operations, and decided the best way to prepare for the project was to find out first-hand what would best keep his plant operating at a high level. So he prepared a trial on influent and effluent troughs on one of the plant’s secondary clarifiers, on which six different coatings systems were applied in an area where they would face near identical exposure.
“We coated those sections of the clarifier and just watched them for a couple years,” recalls Steinbach. “I had some coatings people come to me and tell me that the real proof of these trials would only come 15 years down the road, but in just a couple years it actually told us quite a lot.”
“One, we learned which coatings systems would fail right away, and some of them did. We also saw how the systems dealt with outgassing issues we had been experiencing. And the experience told us something about the vendors we’d be working with.”
The trials gave Steinbach confidence in a single course of action, and by 2005, Spectrum Contracting from Grafton,Wis., was starting a three phase, three-year project using a Sherwin-Williams Envirolastic AR 425 Polyurea system specified by Reukert-Mielke engineer Tom Renner on the Oconomowoc plant.
Built in 1976, the plant serves the needs of about 8,000 households, a couple dozen light manufacturing facilities and two significant food ingredient plants. Capable of managing a peak flow of 9.0 mgd, the plant operates at about 30 percent short of full capacity. While a capacity expansion has long been in future budget plans because of the area’s growth potential, Steinbach knew 10 years ago that some maintenance work was becoming a greater priority.
“The plant was being impacted in two ways,” says the 16-year manager of the plant. “One was from the freeze thaw cycles we experience here and the surface exposure to the elements. But the plant was also being impacted by hydrogen sulfide, and that was a major concern. H2S is our nemesis.”
In a limited 1998 trial, an epoxy system ended up cracking, leading Steinbach to plan his six-system trial in 2000.