2.4 Weyburn-Midale

The Weyburn oilfield in the Williston Basin of Canada was discovered in 1954. The field covers an area of some 210 km2 and has a current oil production rate of about 29,700 bbl/d of medium-gravity crude oil. The development includes 650 production wells and 289 injection wells [13, 18, 19].

From late 2000, Cenovus Energy (formerly EnCana) has been injecting significant amounts of CO2 into the field to improve oil production. The gas is supplied through a 325 km long pipeline from the Dakota Gasification Company's Great Plains synfuels plant at Beleuah, North Dakota. The EOR aspect of the project is depicted in Figure 4. In 2005, Apache Canada implemented a similar CO2 EOR scheme in the adjacent Midale oilfield.

Figure 4 – Schematic of the Weyburn-Midale EOR project [20]

Source: Gagnon, S., C. Rea, A. McGuire, M. McBride Peterson, A. Casey and G. Gill, (2008). "In-depth: Burying the problem", Canadian Geographic, January/February issue 2008.

The two projects combined are injecting more than 2.8 Mt/yr, resulting in the production of an additional 25,000 bbl/d. Not all the CO2 injected in an enhanced oil recovery (EOR) project remains in the subsurface. Some CO2 reaches the production wells. Both operations include equipment to recycle CO2 produced with the oil. Over the life of the projects, the operators envisage storing over 40 Mt of CO2.