The Weyburn-Midale Carbon Dioxide Project (or IEA GHG Weyburn-Midale Monitoring and Storage Project) is, as of 2008, the world's largest carbon capture and storage project. It is located in Midale, Saskatchewan, Canada.
Introduction
The IEAGHG Weyburn-Midale CO2 Monitoring and Storage Project is an international collaborative scientific study to assess the technical feasibility of CO2 storage in geological formations with a focus on oil reservoirs, together with the development of world leading best practices for project implementation. The project itself began in 2000 and runs until the end of 2011 when a best practices manual for the transitioning of CO2-EOR operations into long-term storage operations will be released.
The research project accesses data from the actual CO2-enhanced oil recovery operations in the Weyburn oil field (formerly operated by Cenovus Energy of Calgary before its Saskatchewan operations were sold to Whitecap Resources in 2017), and after the year 2005 from the adjacent Midale field (operated by Apache Canada). These EOR operations are independent of the research program. Cenovus Energy's only contribution to the IEAGHG Weyburn-Midale CO2 Monitoring and Storage Project was to allow access to the fields for measurement, monitoring and verification of the CO2 for the global scientists and researchers involved in the project.
History – The Weyburn oilfield
The Weyburn and Midale oil fields were discovered in 1954 near Midale, Saskatchewan.
The Weyburn Oilfield covers an area of some and has a current oil production rate of ~3,067 m3/day. Original oil-in-place is estimated to be . The oil is produced from a total of 963 active wells made up of 534 vertical wells, 138 horizontal wells, and 171 injection systems. There are also 146 enclosed wells. Current production consists primarily of medium-gravity crude oil with a low gas-to-oil ratio.
The Midale oil field is about in size, and has of oil-in-place. It began injecting CO2 in 2005.
Various enhanced oil recovery techniques were used in the Weyburn field prior to the introduction of CO2, between the 1970s and 1990s. These include additional vertical drilling, the introduction of horizontal drilling, and the use of waterfloods to increase pressure in the reservoir. In October 2000, Cenovus (formerly Pan Canadian, Encana) began injecting significant amounts of carbon dioxide into the Weyburn field in order to boost oil production. Cenovus was the operator and held the largest share of the 37 current partners in the oilfield prior to the sale of local assets to Whitecap in 2017.
History – Injection of CO2
Initial CO2 injection rates in the Weyburn field amounted to ~5,000 tonnes/day or 95 million scf/day (2.7 million m3/d); this would otherwise have been vented to the atmosphere from the Dakota Gasification facility. At one point, CO2 injection by Cenovus at Weyburn was at ~6,500 tonnes per day. Apache Canada is injecting approximately 1,500 tonnes/day into the Midale field.
Overall, it is anticipated that some 40 Mt of carbon dioxide will be permanently sequestered over the lifespan of the project in the Weyburn and Midale fields. The gas is being supplied via a 320 kilometre mile long pipeline (completed in 1999) from the lignite-fired Dakota Gasification Company synfuels plant site in Beulah, North Dakota (See attached image). The company is a subsidiary of Basin Electric Power Co-operative. At the plant, CO2 is produced from a Rectisol unit in the gas cleanup train. The CO2 project adds about $30 million of gross revenue to the gasification plant's cash flow each year. Approximately 8000 tonnes/day of compressed CO2 (in liquid form) is provided to the Weyburn and Midale fields via the pipeline.
During its life, the Weyburn and Midale fields combined are expected to produce at least 220 million additional barrels of incremental oil, through miscible or near-miscible displacement with CO2, from a fields that have already produced over since discovery in 1954. This will extend the life of the Weyburn field by approximately 20–25 years. It is estimated that ultimate oil recovery will increase to 34% of the oil-in-place. It has been estimated that, on a full life-cycle basis, the oil produced at Weyburn by CO2 EOR will release only two-thirds as much CO2 to the atmosphere compared to oil produced using conventional technology.