Carbon dioxide enhanced oil recovery
At the Weyburn oilfield, we’ve demonstrated that oil production from a mature field can be enhanced in an environmentally responsible manner by using and then storing carbon dioxide (CO2) that otherwise would have been vented into the atmosphere. We call this CO2 enhanced oil recovery.
On November 13, 2017, we announced an agreement to sell our majority interest in the Weyburn operation for cash proceeds of $940 million. The sale is expected to close in the fourth quarter of 2017.
The original oil production facilities at Weyburn were built in the mid-1950s. In 1964, waterflooding technology was introduced, which involves injecting produced water back into the reservoir to displace oil from the oil-bearing formation. In 2000, CO2 flooding was introduced alongside waterflooding to maximize oil recovery. Today, about 60 percent of the Weyburn field is under CO2 flood. The Weyburn project is Canada’s largest CO2 enhanced oil recovery operation and is recognized as the world’s largest geological CO2 storage project. From 2000 to 2012, Weyburn was also the site of the International Energy Agency (IEA) Greenhouse Gas Weyburn-Midale CO2 Monitoring and Storage Project, an example of global collaboration and a model for academics, governments and researchers from around the world to learn about CO2 injection and storage.
We’ve safely injected approximately 30 million tonnes of CO2 underground at Weyburn since 2000.
Weyburn’s reservoir (the Midale formation) has favourable conditions, such as temperature, pressure and oil composition, that allow CO2 to act as a solvent. It extracts oil trapped in extremely small pores of the reservoir rock and sweeps it towards the producing wells. Compared to the recoveries normally seen with waterflooding alone, this greatly increases the ultimate recovery of oil from our reservoir.