John previously wrote about how rural roads are going back to the stone age because of the cost of asphalt. The sticky black liquid was the bottom of the barrel in the oil industry, often sold at a loss, to be mixed with aggregates and used for paving. (5% asphalt to 95% aggregate, the asphalt is the glue that holds it together).
There is a lot of it in heavy crude, which is the fastest growing part of the industry (see the Alberta oil sands), which should mean that there is more of it, but in fact that is exactly the problem. According to the Globe and Mail,
Eager to capitalize on the heavy crude growth, refiners across the continent have scrambled to build what's called "coking" capacity. Cokers take those heaviest parts of the barrel and, in simple terms, refine them into more marketable products. That leaves less of the heavy product to make asphalt - and cokers are growing rapidly. Between 2008 and 2013 alone, North America will add more than 18 per cent to its total coking capacity, according to research firm GlobalData.
So where before it was virtually a waste product, good for little more than sealing roofs and paving roads, now it can be refined into gasoline, a much more valuable product. One paving contractor told the Globe and Mail:
"The fundamentals for asphalt are changing all the time. Less sources are becoming available to us."
So asphalt becomes part of a vicious circle; cars are less efficient and burn more gas on gravel roads, so more heavy oil gets refined, meaning more expensive asphalt and more gravel roads. It's a cycle we have to break.
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