Nexen is turning a heavy oil waste product into a synthetic gas to help fuel its steam assisted gravity drainage operation (SAGD) at Long Lake.The project, southeast of Fort McMurray, is the fourth major integrated oil sands project in Canada and the first to feature SAGD and onsite upgrading on a large scale.
With SAGD, steam is injected into an upper horizontal well which heats and loosens the bitumen so it can drain into a lower well and be pumped to the surface. The bitumen is then diluted and sent to a refinery for upgrading into lighter oil products.
But at Long Lake, the bitumen is upgraded to a premium synthetic crude oil onsite with a proprietary OrCrudeTM unit, a gasifier and a hydrocracker.
As part of the gasification process, asphaltene residue from the bitumen (that’s usually waste) is converted into a synthetic gas to run the SAGD and the upgrading operations, significantly reducing the amount of natural gas that’s required.
In fact, compared to most other traditional SAGD operators, Long Lake uses one quarter the amount of natural gas per barrel of oil produced.
While there’s no reduction in emissions using synthetic gas, the project is one step ahead when it comes to carbon capture technologies that are being discussed. Long Lake’s unique gasification process will allow it to capture a pure-stream of CO2, which in turn will make it much simpler to sequester the carbon dioxide underground. The plant at Long Lake was designed to ensure emissions are below regulatory limits and very little surface water is used in the operations.Construction of Long Lake started in 2004 and it started producing synthetic oil in January 2009. Nexen chose the Long Lake site because it had already been used for industrial activity, therefore greatly reducing the land disturbance. Further, Nexen collaborated with Alberta Pacific Forest Industries (APFI) to clear and harvest the trees in the area so the two companies in different industries could share their environmental footprint.