Effectively retrieving oil from sand is a tough challenge. Chevron is using its vast resources of technology and expertise to bring this energy source to market.
Mining Used on Shallow Deposits
At the Athabasca Oil Sands Project's (AOSP) Muskeg River Mine in Alberta, Canada, giant shovels capable of scooping nearly 100 tons of bitumen-bearing oil sands in one bite make the job easier. Workers at mine sites need to extract more than two tons of oil sands to produce one barrel — 42 gallons — of usable crude. Chevron holds a 20 percent interest in the project.
In order to extract the bitumen from the oil sands at the Muskeg River Mine, the ore is mixed with warm water to create a slurry. This slurry is fed into a processing unit where the bitumen is separated from the water and sand mixture. The extracted bitumen is diluted with a special solvent and then sent via pipeline to an upgrading facility near Edmonton. There it is transformed into a wide range of premium-quality, low-sulfur and low-viscosity synthetic crude oils.
Most significant oil sands resources are in the Canadian province of Alberta. Some of the bitumen, approximately 20 percent, is shallow enough for surface mining. But other significant resources are located deeper underground and cannot be mined. Recovery of these will require a different solution.
Different Approach to Deeper Resource
The Chevron-operated Ells River Appraisal Project, 26 miles (42 km) southwest of AOSP, requires a different approach. Because the bitumen is buried much deeper, mining extraction techniques are not cost-effective. Instead, wells will be drilled to recover the bitumen. To loosen the bitumen and encourage it to flow into the well bores, Chevron is considering a range of thermal and enhanced-recovery technologies.
Since the Ells River area is largely unexplored, the company is working to define the extent and quality of oil sands there. In 2008, we completed appraisal drilling and a seismic program. Another seismic program was completed in the first quarter of 2009.
Appraisal operations are limited to the winter months, when the ground is frozen, to reduce potential surface impact from heavy equipment. And because the operations are located in a Woodland Caribou Zone, Chevron has developed a Caribou Protection Plan that further restricts timing of the appraisal activity to avoid caribou calving season.
In June, 2009, Chevron placed the Ells River project on hold.
The Future Is Now
The Chevron Technology Center in California also is developing new methods to coax heavy oil from oil sands at the Ells River Project and other sites throughout the world.
Updated: July 2009