June 2017 Vol. 25, No. 2

Current Issue | Previous Issues | Subscribe | Download

Minnesota LTAP Exchange banner

Should you use recycled materials to melt ice and snow on your roads?

Ice cubes

Photo: Shutterstock

711 slushee

Ice formed in the bottom of this test sample. Photo: Ron Wright

At the 2017 Road Salt Symposium, Ron Wright, manager of the Idaho Department of Transportation laboratory and a founding member of Pacific Northwest Snowfighters, talked about using recycled products to deice roads.

Does it work?

Wright said: “Why should you use a recycled product? Will it melt ice by itself? Test it by putting some on ice cubes in the freezer at zero degrees. Or if it’s an additive, mix blends with different ratios and put them in the freezer. You can test it yourself and see some basic characteristics or send it to our lab.”

One reason it’s important to know the freezing point of materials is to determine if the products can be stored outdoors during winter. “If it freezes at 10 degrees, you’ll have a problem when the temperature goes below 10 and you’ve got a 20,000-gallon tank of stuff that looks like a big 7-Eleven slushy!”

He showed the test sample (see photo to the right)—an additive material in which ice had formed at the bottom. “When you pour it into a number 10 sieve, which is about the size of the filter on most trucks, you get this coagulant that will jam up your system.”

Will it improve another product?

Wright said Ice Ban® and other agricultural byproducts allow chlorides to stick to the road better and work longer. “When we first started using Ice Ban it had a strong odor! However, that product has evolved and is better now,” he added.

Is it consistent?

Wright said he calls some products sent to his lab “Hollywood samples because they’re the best of the best. But is it going to do what it’s supposed to do every time? Maybe you need some quality-control testing.”

What will it cost?

When considering a new product, Wright said it’s important to run a cost-benefit analysis: “What’s it going to cost to transport? Are there special mixing requirements or does it require special equipment?” He added that it’s important to know the disposal cost for leftover material, which will change depending on whether the material is going to a landfill or into the sewer system. For example, cheese whey requires additional processing at a sewer plant. He also stressed the importance of knowing the cost to the environment and the cost of damage to infrastructure. In the U.S., remediation of infrastructure corrosion costs over $26 billion a year, he noted.

What’s the pH?

One important fact to know about anything you plan to put on your roads, Wright said, is its pH: “pH tells you if a material is acidic, basic, or neutral, expressed as a number between zero and 14. Seven is neutral; below seven is acidic; above seven is basic. Fruit juice, coffee, and vinegar are acidic; ammonia, lime, and baking soda are basic. Pacific Northwest Snowfighters’ acceptable pH range is between 6 and 9. We’re concerned about damage to groundwater, surface water, soil, vegetation, and people. We also don’t want you using stuff that will burn the fur off you!

"pH is also important because you need to look at the corrosion factor, especially if your roads are made out of limestone or concrete. I had some people propose a product that had a pH of 1.5, but it also contained a corrosion-protection component, so they wanted an exemption for it. Out in the lab, I tested it on concrete, and it foamed up like Alka-Seltzer! I said, ‘Who’s going to call our governor when the interstate foams up?’ I never saw them again.”

—Richard L. Kronick, LTAP freelancer