Revolutionary Road (materials)
The cost of replacing crumbling roads will tumble, with the introduction of an Arizona Chemical additive that enables more low-cost recycled asphalt to be used.
Could a biobased $100 billion dollar savings be in the offing?
If you haven’t noticed, US roads are a shocker. In fact, in 2013, the American Society of Civil Engineers gave the US a “D” grade for road conditions and capacity, and reported:
“32% of America’s major roads are in poor or mediocre condition, costing U.S. motorists who are traveling on deficient pavement $67 billion a year, or $324 per motorist, in additional repairs and operating costs. While the nation has seen some improvements in pavement conditions due to a short surge of investment from the American Recovery and Reinvestment Act, these were not sustained, long-term investments.
Don’t forget road care.
The cost of unscrewing up the mess will only get worse, the ASCE says:
“After 25 years the cost per lane mile for reconstruction can be more than three times the cost of preservation treatments over the same time period, which can lead to a longer overall life span for the infrastructure.”
Change vs more of the same.
There’s consensus about the problems, but not about the solutions, because most of them come down to raising tax-and-spend solutions aimed at doing “more of the same”. A report from the Center for American Progress is relatively typical:
Rebuilding our crumbling infrastructure is a daunting, but achievable, goal. The nation needs an additional $129.2 billion per year investment to meet the current backlog of infrastructure repairs and improvements, according to a report by American Progress’s Donna Cooper, “Meeting the Infrastructure Imperative: An Affordable Plan to Put Americans Back to Work Rebuilding Our Nation’s Infrastructure.”
The justification for such massive investment is usually the multiplier effect. As CAP argues:
Mark Zandi, chief economist at Moody’s Analytics, found in 2011 that new federal spending for infrastructure improvements to highways and public schools would generate $1.44 of economic activity for each $1 spent. In fact, the Congressional Budget Office found that infrastructure investments had one of the strongest economic impacts of all the policies included in the American Reinvestment and Recovery Act.
But what happened to “change” vs “more of the same”? Are there ways to change the way we construct and maintain roads that reduces cost and improves performance?
The materials, stupid.
Turns out that Arizona Chemical may have found a way. In surveying the authorities who maintain the roads beneath our feet, the company’s roads and construction team found a persistent yearning for transformative materials. “They spoke of reducing consumption of virgin material, of an ability to reuse materials sitting in piles or industrial sites, and a real need to reduce cracking,” Arizona Chemical’s Raquel Silverberg told The Digest.
True enough, there are millions of tons of old pavement, old roads — can they be recycled? Yes, they can — the material is called reclaimed asphalt pavement, or RAP. Using RAP in road construction has significant benefits for agencies, contractors and taxpayers in cost containment.
But using recycled material has its drawbacks. The higher the percentage of RAP blended with virgin mix results in lower performing roads. Faster degradation. More rutting, more cracking, more water seepage. Your basic nightmare. For that reason, typical RAP percentages run between 20%-30%.
“We put our best scientists onto it,” said Silverberg. “The needs became compelling, but we had to go back to beginning.”
Finding a solution in pine trees.
The result is an additive to RAP — and the additive itself is biobased and renewable, that is enabling percentages of 50% or more with performance equal to pavement containing 100% virgin mix. Arizona Chemical calls it Sylvaroad RP1000 Performance Additive. It’s made from Crude Tall Oil (CTO) derived from pine trees, and it’s non-hazardous.
In a ton of asphalt mix,” Silverberg told The Digest, “there’s 95% aggregate and rest is bitumen. CTO is a building block for us, and it is very much like “young bitumen”, it has many of the same chemical components vs petroleum distillate. What we’ve done is refine it and reacted it and we created a specialized molecule.”
You don’t need much. “In every ton, there’s less than a half percent of additive required. You can pave 2 lane miles with one ton of additive,” SIlverberg said.
How much can municipalities and road authorities save?
According to AsphaltRecycling.com, “Contractors and municipalities can recycle their RAP materials for approximately $18.00 /ton using a PT-PRO Series Recycler. If hot mix purchased at the asphalt plant cost $78.00/ton, then there is an effective savings of $60.00/ton.”
How does that translate to road building? According to The Scruggs Company, they use roughly 1500 tons of asphalt to lay a two-inch thick layer for a 24 foot-wide road, for one mile. So, moving from say 25% to 70% recycled content, the savings could in the range of $40,000 per mile for a two-lane road — less the cost of the additive.
With 4 million miles of roadway in the US — it’s not hard to rack up $100 billion in savings, based on the stats that Scruggs and AsphaltRecycling.com cite.
Back to Arizona Chemical. The company did extensive trialing and has now transitioned Sylvaroad into a a commercially sold system. Lab tests and trials have shown mixes with Sylvaroad and RAP content of up to 75% have met rigid rutting, cracking and water resistance specifications, and trials have been done in the EU, Asia and the US east coast, with trials done above 70% RAP content in the northern EU and with one customer trialing at 80%.
“To get them to 50% it makes a big financial impact,” says Silverberg. “We have decades in the company of using biorenewable materials, and bottom line, first it must perform, then the green aspect completes the value proposition and makes it stronger.”
What about concrete roads?
The alternative material is concrete, according to Public Works magazine. “Until 2008,” they noted, “asphalt captured roughly 94% of all pavements in the U.S. market. During this time, asphalt enjoyed a lower initial bid and a life-cycle paving cost advantage over concrete, according to a Portland Cement Association (PCA) analysis. Between 2003 and 2012, concrete prices rose 37% while asphalt soared 200% — highlighting that another inhibitor to road construction has been the cost volatility associated with bitumen.
The Bottom Line
So there you have it. A daunting infrastructure challenge. A recycling option that works economically, but only with low percentages. A biobased chemical to the rescue, demonstrating that the chenges that are coming are not only in the vehicles and the fuels, but in the roads they drive on.
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