Oil Shale Sub-economic Resource

Oil shale  a sedimentary rock containing an organic material called kerogen.  Kerogen is a solid in the rocks.  Where are the deposits located?

Green River Oil Shale Formation

Extraction Surface retorting- similar process to surface mining and then the rock is heated and the kerogen is extracted and processed. Problems-  where to put the excess shale (ton of rock/3 barrels of oil  net energy yield is low(energy intensive)  spent shale may leach toxic materials  need large quantities of water to process  retorts produce air pollutants

Another Extraction Method In situ Retorting-  Deposits fractured by explosives and while in place in the ground. Underground fires are started and the kerogen liquefies and is removed from the ground. Problems  Ground water seeps in to extinguish fires.  Shale fractures unevenly so difficult to maintain combustion process.  More sulfur emissions

Availability  Sub economic Resource  U.S. has 2/3 of known oil shale.  2-5 trillion barrels of oil  Could meet our energy needs at present consumption rates for 400 years.

TAR SANDS  sand deposits impregnated with petroleum like substance known as bitumen.

Problems  Strip mined  Hot water processing  Large deposit in Alberta, Canada- Venezuela-U.S. six states have deposits  Not even close to meeting oil needs in US  Expensive, has gone from sub-economic resource to reserve

Frozen Fuels-  Frozen form of natural gas-methane hydrate found on ocean floor. Frozen as a result of great pressure.