Enhanced Oil Recovery and CO2 Storage in the Weyburn Oilfield: An Economic and Environmental Win-Win

Marty Hewitt
EnCana Oil and Gas Partnership, Calgary, AB

The geological storage of CO₂ in oil reservoirs offers a win-win approach to mitigate climate change while enhancing production from mature oilfields.

The EnCana Corporation operated Weyburn oilfield is Canada's largest commercial enhanced oil recovery (EOR) project and the world's largest CO₂ sequestration project. Discovered in 1954, the field covers over 70 square miles in southeastern Saskatchewan and is one of the largest medium-sour crude oil reservoirs in Canada, containing approximately 1.4 billion barrels of OOIP of which 380 million barrels have been recovered to date. CO₂ has been injected into this 25 to 34 degree API oilfield since 2000, making valuable use of a by-product that would have otherwise been emitted from Dakota Gasification Company's coal gasification facility near Beulah, North Dakota. The EOR project is estimated to recover an incremental 155 million barrels of oil. The field is currently producing close to 30,000 bbls/d and is projected to store approximately 30 million tonnes of CO₂ over the EOR life, equal to taking over 6 million cars off the road for one year.

Weyburn also serves as the site for the International Energy Agency (IEA) GHG Weyburn CO2 Monitoring and Storage Project. The first phase of this multi-party research project concluded that storage of CO₂ in an oil reservoir is viable and safe over the long term, thus providing a good foundation towards development of solid policy, regulations and operating practices for future CO₂ storage/EOR. This project also demonstrates the power of collaborative partnerships between governments, researchers and industry to unlock value through technology.