Oil sand is a mixture of bitumen, sand and water. Because it does not flow like conventional crude oil, it must be mined or heated underground before it can be processed.
The hydrocarbon resource found in Canada’s oil sands is called bitumen. Bitumen is very viscous – it doesn’t flow like conventional crude oil — and therefore requires special extraction methods to get it out of the ground and into a state where it is fluid enough for transportation to refineries. Once processed, the extracted oil sands bitumen is then refined into gasoline and other hydrocarbon products, just like any other oil resource.
While approximately 20 percent of total recoverable oil sand reserves are close enough to the surface to be recovered through surface mining, the vast majority of oil sands deposits — and all ConocoPhillips Canada’s reserves — average depths of 1,300 feet below the surface. In-situ recovery techniques, such as steam-assisted gravity drainage (SAGD) have to be used to extract these deep deposits of bitumen without removing the soil and materials above it.
SAGD involves injecting high-temperature steam underground through a horizontal well to melt the bitumen, allowing it to flow to an adjacent horizontal well. From there, it is pumped to the surface for further processing. These pairs of horizontal wells are drilled from a central well pad in order to minimize land disturbance. Steam injection and oil production happen continuously and simultaneously. The resulting mixture of bitumen and water (which is condensed from the steam) is then piped from the producing well to a nearby upgrading plant, where the bitumen is separated from the water and treated. The produced water is then recycled to steam generators to generate new steam, which then travels through above-ground pipelines back to the wells for injection. The produced bitumen is treated to create a synthetic crude oil that can be transported to a refinery. Alternatively, bitumen may be mixed with a diluent (usually natural gas condensate) to create a blend that can be transported via pipeline to refineries.