Mining - Biodegradation of oil sands into methane

An idea founded long ago is on the rise again. Scientists said recently in the journal Nature they can radically speed up the underground bacterial fermentation that turns Canada's tar-like Athabasca sands into natural gas at far less cost and with far less environmental pollution.

This is huge global news because the world has about 6 trillion barrels of such heavy oil, more than 20 times the proven oil reserves in Saudi Arabia. They're focused in Canada's Athabasca, in Venezuela's Orinoco tar belt, and in the oil shale of the U.S. Rocky Mountains. All may be economically recoverable with bacterial refining.

Dr. Steve Larter of the University of Calgary says understanding how anaerobic bacteria ferment heavy oil into clean-burning methane underground opens the door to recovering the gas from deeply buried oil sands.

"The main thing is you'd be recovering a much cleaner fuel," he says. "Methane is, per energy unit, a much lower carbon dioxide emitter than bitumen."

A separate family of microbes that produces CO2 and hydrogen from partly degraded oil offers a way to capture the CO2 from the tar sands as methane, for burning in a closed-loop system would keep the CO2 out of the atmosphere.

Mining - Analogy for working with Oil Sands

Here is the best simple analogy for describing the challenges facing the bitumen extraction.

Alberta writer David Finch, the author of Pumped: Everyone's Guide to the Oil Patch, suggests this experiment: “Take molasses out of your kitchen cupboard, put as much sand in there as molasses, stir it up, and then put it outside where it gets cold and thick and won't flow – well, that's what the tar sand is like. It's extremely hard to work with, and it wrecks all your equipment.”
The muddy dirt clogs gears and conveyors; the sand corrodes pipelines. To mine bitumen, the land must first be cleared and drained. Clumps of sand are shovelled out and then mixed with water and heated, to force the hydrocarbon to rise to the top. It is then processed in an “upgrader” to produce synthetic crude before being sent to a refinery and turned into gasoline and heating oil.
Estimates vary, but environmental groups says it now takes two to four barrels of fresh water from the Athabasca plus 750 cubic feet of natural gas and about two tons of oily sand to produce one barrel of oil. The process produces two to three times the carbon emissions of a conventional oil well and creates toxic waste water, called tailings, that cannot be allowed back in the river.