CO2 Recovery and Sequestration at Dakota Gasification Company

The Great Plains Synfuels Plant, located near Beulah, North Dakota, is the only commercialscale gasification plant operating in the United States that produces Synthetic Natural Gas (SNG) from coal. The plant is owned and operated by Dakota Gasification Company (DGC), which is a subsidiary of Basin Electric Power Cooperative (BEPC), based in Bismarck, North Dakota. The concept for the Synfuels Plant began in the 1970’s and grew from a desire to alleviate the United States dependence on foreign oil. Today upwards of 150 million standard cubic feet per day of SNG are produced and exported to consumers throughout the Midwest via the Northern Border Pipeline. Numerous by-products, including anhydrous ammonia, ammonium sulfate fertilizer, phenol, cresylic acid, krypton/xenon, naphtha and carbon dioxide (CO2) have been added to the list of products enhancing the viability of the facility. Since the conception of the plant, the idea was envisioned of adding CO2 for enhanced oil recovery (EOR) to the list of by-products. In October 2000, this became a reality when Dakota Gasification Company began exporting up to 95 million standard cubic feet per day of highpressure CO2 from the Synfuels Plant. The CO2 is delivered through a 205-mile pipeline to EnCana Corporation’s Weyburn Oil Fields in Saskatchewan, Canada, where it is injected into depleting oil formations to increase production and lengthen the life of the field. The feed gas to the carbon dioxide unit was previously a low value fuel, and has now become a source of revenue to the company. Although this project has presented many challenges to both Dakota Gasification and EnCana, it has proven to be a technical and economic success. In addition, the EOR project has led to an