Up until yesterday, I thought the filthiest of the fossil fuels was brown coal; but it seems there is a more emissions intensive substance – petcoke.
Petroleum code is a by-product of refining oil and is almost pure carbon. There are a few nasties thrown in such as sulphur, which is present in quantities double the amount of that found in coal.
On a per-unit of energy basis, petcoke emits 5 to 10 percent more carbon dioxide than brown coal.
We’ve heard a lot about the damage tar-sands mining does; but I never really gave much thought to the by-products such as petcoke.
According to The Guardian, 60 – 130lbs of pet-coke is created for every barrel of crude that comes out of the Alberta tar sands’ operations – and stockpiles are mounting. A three-story mountain of the waste covers an area the size a city block in Detroit.
So what to do with all this petroleum coke? Burn it for power generation of course.
I’m all for using waste products in a useful way, but in addition to the CO2 and sulphur, the burning of petcoke also releases mercury, lead and soot; so this is a waste product that just keeps on damaging.
While petroleum coke can’t be used for power generation in the USA due to the sulphur content; Detroit’s petcoke, which has its origins in Canadian tar sands oil, is going to be shipped back to Canada – and they’ll burn it there. It doesn’t really matter where it’s burned – there will be a global impact.
With petcoke factored in, there is 24 percent more carbon dioxide embedded in a barrel of tar sands bitumen than in a barrel of light oil according to a report titled “Petroleum Coke: The Coal Hiding in the Tar Sands” (PDF).
It seems oil extraction from Canada’s tar sands being labelled the “most environmentally destructive project on earth” is no exaggeration. That such a beautiful region is being turned into something akin to Mordor is tragic enough without all the additional threats posed by the mining of what lies beneath.