Steam Assisted Gravity Drainage
Steam Assisted Gravity Drainage (“SAGD”) is a widely used thermal production technology which extracts bitumen from Alberta’s subsurface oil sands deposits. Athabasca is utilizing this in situ production technology to tap the potential of the oil sands in the stacked Wabiskaw and McMurray formations.
Developed by the Canadian oil and gas industry to unlock northern Alberta’s vast bitumen resources, SAGD employs a horizontal well pair configuration – an upper steam injection well and a lower production well which is drilled in parallel, some five metres below. Steam is injected into the oil sands reservoir, creating a steam chamber that expands vertically and horizontally within the geological formation. Heat transfers to the bitumen, reducing its viscosity and enabling it to flow – by gravity drainage – into the production well where it is pumped to the surface for processing.
The water required to generate steam for SAGD operations is typically sourced from local subsurface aquifers. Athabasca’s development plans involve recycling more than 90 percent of the water required for steam generation. The SAGD production technology has a significantly smaller surface footprint than oil sands mining operations and it does not require the use of tailings ponds.