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Testing ground
MeadWestvaco sees worldwide market for new asphalt additive
By Dennis Quick
Senior Staff Writer
Earlier this month, Dorchester County became the South Carolina testing ground for a new asphalt-paving innovation created by MeadWestvaco Corp.’s Specialty Chemicals division in North Charleston.
Called “Evotherm,” the product is touted as an additive that makes the production and application of asphalt more environmentally friendly and energy efficient.
With Evotherm, less heat is required to produce the asphalt. As a result, carbon dioxide and other greenhouse gas emissions, at the production plant as well as the pavement site, are decreased by 46% to 58%. Fumes and odors are reduced and Evotherm-mixed asphalt is more durable, MeadWestvaco officials and asphalt industry experts said.
“We think roads will last longer,” said Andrew Crow, business manager for MeadWestvaco’s Asphalt Innovations in North Charleston.
Evotherm is a sustainable product made from tree fats and oils, both waste products from MeadWestvaco’s North Charleston paper mill, Crow pointed out.
And the worldwide market potential for Evotherm is huge, he added.
Environmental concerns, ranging from the Kyoto pact to reducing global warming by reducing carbon dioxide emissions to citizens groups opposed to the smell of asphalt produced near or applied in their neighborhoods, led MeadWestvaco to create Evotherm, Crow explained.
With Evotherm, MeadWestvaco is the first U.S. company to create a “warm-mix” asphalt product, a technology originally conceived in Europe, Crow said. Of the three warm-mix asphalt technologies that have been tested in the United States, two come from European companies and the other is from MeadWestvaco, Public Works magazine reported in May.
Since its 2005 launching, Evotherm has been tested in about 25 cities throughout the world, including Beijing. Commercial sales so far have been small as demonstrations and trials are still ongoing. In the majority of cases, MeadWestvaco donates Evotherm to an asphalt-production company and the state covers the paving costs, Crow said.
Because of its environmental and energy-efficiency advantages over traditional “hot-mix” asphalt, warm-mix asphalt most likely will become the predominant road-pavement method in 10 to 15 years, said Chris Davis of North Charleston-based Sanders Brothers Construction Co., which applied about 400 tons of Evotherm-blended asphalt to pave a portion of road during the demonstration of the product in Dorchester County’s Archdale subdivision.
Generally, traditional hot-mix asphalt costs about $50 per ton, said Davis.
Asphalt mixed with Evotherm costs $3 to $5 more per ton, Crow said.
However, experts said the increased cost could be offset by lower fuel costs to produce the environmentally safe asphalt.
“We don’t know for sure how much that fuel savings will be,” Davis said. “That’s why more research is still needed.”
Usually, asphalt pavement is manufactured at temperatures between 300 and 350 degrees Fahrenheit. Using Evotherm, asphalt can be produced at temperatures more than 100 degrees lower. The savings amounts to a 55% reduction in fuel to produce asphalt pavement, according to MeadWestvaco.
“We find Evotherm’s ability to lower energy demands and emission levels extremely promising and welcome the opportunity to learn more about the potential for this paving innovation,” said Bill Simpson, senior vice president of Sanders Brothers Construction Co.
Because MeadWestvaco has a history of producing asphalt emulsifiers and other chemical products, creating Evotherm was a “natural progression” for the company, which invested between $1 million and $5 million in the product, Crow said.
Asphalt mixed with Evotherm underwent a rigorous road test at Auburn University’s National Center for Asphalt Technology in Alabama. Six 18-wheeler trucks drove 24 hours a day for several days on a track made of asphalt-blended Evotherm, and the asphalt showed no signs of rutting or other degradation, according to a NCAT report released in June.
The South Carolina Asphalt Pavement Association, which includes about 35 companies in the state’s asphalt industry, sponsored MeadWestvaco’s Evotherm demonstration in Dorchester County and wants to educate more of the state’s asphalt producers and paving contractors about warm-mix asphalt, said David Herndon, the association’s executive director.
“Warm-mix ages the asphalt less and roads last longer,” Herndon said.
Roads that are more durable and require less maintenance save money for taxpayers, he added.
Still, Herndon said he and others in his association want to see more tests done on Evotherm before they start replacing hot-mix with warm-mix asphalt.
“We’re still looking into it,” he said.
Dennis Quick is senior staff writer at the Business Journal. E-mail him at dquick@charlestonbusiness.com.
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