What is Tar Sands?
Tar Sands (also known as oil sands) contain a combination of clay, sand, water and a heavy dense viscous oil known as bitumen. Through advanced mining processes, bitumen can be extracted from the sand and turned into refined oil. The oil sand is referred to as a "non-conventional oil" or "crude bitumen" in order to differentiate it from traditional crude oil produced by oil wells. The bitumen found in tar sands cannot be pumped from the ground in its natural state, leaving alternative mining methods to remove it from the ground. Tar sand deposits are mined utilizing techniques such as strip mining, open pit techniques, and underground heating (Steam Injection) to extract the oil.
The complex process of recovering oil from tar sands involves many steps in order for the oil to be profitably extracted and upgraded to a usable product. The recovery process typically involves the following steps:
- Extracting the oil from the sand
- Separating the bitumen from the clay, sand, and water which make up the tar sands.
- Bitumen needs additional upgrading
- Diluting the bitumen with lighter hydrocarbons to pass through pipes easier
Tar sands (oil sands) naturally occur in large quantities throughout the world with some of the largest amounts found in Canada and Venezuela. Until recently, tar sand mining was never even considered when discussing the world’s oil reserves. Today however, it is becoming a viable option due to increasing oil prices and technological advances making the oil extraction possible.
Tar sands falls under the "Non Conventional" category. This is one of three generally recognized categories defined by BP (British Petroleum).
Types of Oils as defined by BP:
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Proven Reserves
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BP defines this as "the estimated quantities of oil which geological and engineering data demonstrate with reasonable certainty to be recoverable in future years from known reservoirs under current economic and operating conditions." In short, economic conditions determine which category an oil falls under |
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EUR (Estimated Ultimately Recoverable) oil
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This category of oil describes that which is "yet-to-be-found" oil. They incorporate oils that are infeasible to recover because of economic or technical reason.
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Non Conventional
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This category includes oil which comes from from coal, oil shale, oil sands, tar sands, bitumen, heavy and extra heavy oil, deep water oil, polar oil and natural gas condensates. |
