Citizens of Detroit are concerned by a three-story pile of petroleum coke that covers an entire city block, which continues to grow in size each day along the bank of the Detroit River. The coke, an unwanted by-product of refining Canada’s tar sands, is produced by a refinery owned by Marathon Petroleum, which has only been refining tar sands oil since November.

The pile in Detroit is not the only one! As more tar sands enters US markets to be refined on US soil, the number of similar coke piles begin to build up. Canada has its own 79.8 million tonne stockpile formed from the initial refining phase that extracts the oil from the bitumen in preparation to be transported south to US refineries.

Kerry Satterthwaite, a petroleum coke analyst at Roskill Information Services, stated that coke is normally used in the steel industry, or in producing aluminium, however the high sulphur content of this coke makes that impossible. “It is worse than a byproduct. It’s a waste byproduct that is costly and inconvenient to store, but effectively costs nothing to produce.”

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The Environmental Protection Agency has stopped issuing licenses to burn petroleum coke in the US due to its high sulphur, and high carbon content, however the Charles and David Koch have managed to find a market for the waste, and through their company Koch Carbon have bought the pile in Detroit, and any more coke that is produced by the refinery there.

Overseas companies, and countries, that are less scrupulous than the US when it comes to protecting the environment and reducing greenhouse gas emissions, such as China and Mexico, buy the coke off Koch Carbon and burn it as a cheap alternative to low-grade coal.

Lorne Stockman, who recently published a study on petroleum coke, explained that it is “the dirtiest residue from the dirtiest oil on earth.”

By. Charles Kennedy of Oilprice.com