Petrobank tries new twist at oil sands project

Predicts success of Toe-to-Heel Air Injection at Whitesands could mark sea change in how energy is wrung from ground

CALGARY — The crude oil produced by Petrobank Energy and Resources Ltd.’s Whitesands operation doesn’t appear noticeably different to that produced anywhere else in Alberta. However, the oil represents not only a realization of the company’s dream, but a potential sea change in how Canadian companies wring energy from the ground.

Whitesands is an unimposing oil sands project southwest of Fort McMurray that’s been in operation for about a year. Operations there are very different from other companies’ attempts to extract crude from Alberta’s oil sands.

Most companies pump steam into their reservoirs to move the putty-like deposits, a process called steam-assisted gravity drainage (SAGD). But this consumes a lot of costly natural gas.
Calgary-based Petrobank has taken a different route at Whitesands, injecting hot air into the ground to force the bitumen – the heavy crude produced from the oil sands – to the wells. “This is what all our work is for,” says Dave Reddecliff, operations manager at the plant. “It might look simple, but it’s also really exciting. To me, this is the answer for the oil sands.”

The method, Toe-to-Heel Air Injection or THAI, is based on techniques that have been around since the 1920s. It is used in countries such as India, Kazakhstan and Romania. Hot air is injected down one vertical well, creating a combustion front that forces the crude toward a second vertical well, where it is extracted.

The process has historically been inefficient, as the air has a tendency to break into the second well, ending production. To overcome those problems, Petrobank has added a twist to the system. Like SAGD, THAI uses a horizontal extraction well, employing gravity to increase the proportion of crude recovered.

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