A massive liquid fertilizer tank is insulated with spray foam

It’s the biggest job I’ve done and it’s the biggest one I’ve seen done in the industry in a long time.

The Corn Belt has consistently been one of the most productive agricultural regions in the world, due in part to the efficient transportation of not only the harvested crops, but their precursor: fertilizer.

Scattered about this Midwest region are fertilizer production and distribution centers that feed the plants that in turn feed the United States. One such facility, which supplies liquid fertilizer to the Corn Belt from western Iowa, impacts nearly every corner of the region.

I saw tankers from seven different states pull up, Scott Waste recalled, further saying that the facility was constantly active with both rail tankers and tractor-trailers coming in and taking fertilizer out. It was amidst this constant commotion that NES Spray Foam Insulation, which is owned by Waste, was tasked with insulating one of the largest fertilizer storage tanks in the region.

Storage Concerns

The tricky thing about storing liquid fertilizer is that its temperature must be maintained within certain thermal boundaries in order to maintain its quality. Basically, it can’t get too cold during winter months, nor too warm during summer months. When considering that fertilizer is typically stored in massive, building-sized tanks at these distribution centers, temperature regulation is not just critical, but difficult.

That being said, insulating the storage tanks is the most efficient way to mitigate the difficulties of regulating the temperature of tens or hundreds of thousands of gallons, or more, of liquid fertilizer. What’s more, the only feasible material with which to insulate these enormous industrial tanks is spray polyurethane foam board, fiberglass and cellulose won’t cut it.

With that in mind, the company that operates the western Iowa facility, as well as several others in the region, began an insulation initiative for their fertilizer storage tanks in recent years. That’s how NES, with well over a decade of SPF industry experience, entered the picture. While NES has previously completed several tanks for the client, the one in western Iowa remains the standout.

A Formidable Undertaking

It’s the biggest one I’ve done and it’s the biggest one I’ve seen done in the industry in a long time, Waste said about the tank. It’s over 80 feet in diameter, over 3 stories tall and has a capacity in excess of 1.1 million gallons. The sheer size of the tank made the project daunting enough, but its contents further complicated the application.

One-third of the tank was filled with product and the temperature difference was approximately 15 degrees from the empty tank section to the section with product, said Waste, who measured the thermal variance with an infrared temperature gun. Needless to say, the presence of the colder substrate presented a problem for NES.

We really had to change our spray pattern and technique when it came to that joint of existing material and empty tank, said Waste, who relied on his experience as a spray applicator in Minnesota to properly plan for the fertilizer tank application. His strategy was to first lightly texturize the colder areas.

You need to do what I call ‘pillow’ the liquid towards the object as fast as you can pull the trigger and move the gun, Waste explained. You just want dots, and those dots are what you’re going to adhere your foam pass to.

It was critical that the texture wasn’t subsequently sprayed with a heavy two-plus-inch pass of foam, but rather two ‘simple’ passes, an inch or so in thickness, in order to prevent shrinkage. Waste stressed that this technique isn’t for the novice sprayer, and furthermore that industrial applications like this require extensive experience on the part of the spray applicator.

Inexperience, as Waste sees it, can lead an applicator to either bungle an intricate project like this, or avoid it altogether. In fact, NES’s involvement with this client’s series of tank applications came as a result of another local spray foam firm essentially deferring the projects into NES’s hands. Waste considers this a win-win situation, as the prior contractor still gets commission, while the customer gets a properly insulated tank from NES.

The Application

Overspray was a major concern during the project. This isn’t usual for NES’s applications in Iowa because of the flat terrain and high winds during the springtime. Both the hourly arrival of tractor trailers and tank’s location within the facility train tankers parked 40 feet to the north of it and a newly-constructed metal pole building 50 feet to the east provided for a tricky setting for the application. Everything in the immediate vicinity, especially the railroad tankers parked nearby, was covered by plastic tarps or visqueen sheeting.

Utilizing a boom lift was a necessity to insulate the sides of the tank, and NES used one to spray everything higher than six feet off the ground. When it came to the insulation itself, the client was very specific, wanting three inches of foam topped with 60 mils of acrylic coating. NES utilized CertaSpray 2 lb. closed-cell foam, made by CertainTeed, to insulate the tank and Uniflex acrylic coating, made by Sherwin Williams, to coat the foam.

Due to complications resulting from high winds and heavy rains, the entire project took three weeks from start to finish. When it was completed, the project marked the 9th tank application NES had completed for the client a track record that speaks to how satisfied they are.

It was the biggest, baddest thing I’ve seen to date, Waste reflected. It turned out perfectly.

About NES Spray Foam InsulationÂ

Based in Minnesota, NES has over 15 years of experience in the SPF industry and serves the entire United States. NES performs insulation, roofing and coatings applications for residential, commercial, industrial and agricultural projects.