US says CO2 injection could quadruple oil reserves
Reuters linkThe DOE said 89 billion barrels could potentially be added to current proved U.S. oil reserves of 21.9 billion barrels through injection of carbon dioxide, the main gas that most scientists believe is warming the earth.
The DOE gave no time frame for when the extra barrels could be added.
The amount is about what the United States, at current demand, uses in 12 years.
Adding billions of barrels in reserves is dependent upon the availability of commercial CO2, the DOE's fossil energy office said.
"Next generation enhanced recovery with carbon dioxide was judged to be a 'game changer' in oil production, one capable of doubling recovery efficiency," DOE said in a release.
And from another site
http://www.itp.net/business/features/de ... &category=For energy producers, injecting CO2 can also facilitate enhanced oil recovery (EOR). Under this process, CO2 is injected into the reservoir via wells in order to reduce the viscosity of the trapped oil so that it flows more easily. Water is injected in alternating cycles with CO2 to sweep oil to the producing wells that pump it, along with CO2, produced water and any associated natural gas to the surface. Then, the CO2 and the associated natural gas are separated and taken away for additional processing. Natural gas liquids are extracted, and the CO2 is re-injected while the oil and produced water are separated at a central tank battery, and the oil is then piped to holding tanks.
This technology is by no means new; in fact, it has been practiced for some time in the US and Canada, notably in the West Texas Permian where this form of EOR accounts for 20% of the region?s total oil production.
There are several reasons why CO2 capture and storage (CCS), both on its own and for EOR purposes, have not become more widespread. As well as safety concerns, these include the fact that CO2 capture costs can be high, and, in the case of EOR, CO2 injection is costly at lower oil prices; however, today?s higher oil prices have made it a much more attractive proposition.
There are also some new groundbreaking R&D projects underway, most importantly, at the Weyburn oilfield in the Williton Basin, southeast Saskatchewan, Canada. In 2000, Canadian oil firm EnCana began injecting significant amounts of CO2 into the field -- first discovered in 1954 -- to boost oil production.
The first C$40-million, four-year phase of this project has been very successful. ?It?s shown us that the reservoir we chose for EOR and CO2 storage is competent and capable of storage,? says Mike Monea, executive director of Canada?s Petroleum Technology Research Centre (PTRC), which conducted the study.
?The EOR exceeded our expectations, and it was very efficient, and the flood mechanism worked perfectly.? The Weyburn field with its 500 wells, Monea admits, ?should have been dead by now.? Production from each well was averaging just five to six barrels per day, however, following CO2 injection, this rose in some cases to 1,000 barrels per day. Now, PTRC expects 160 million barrels of crude will ultimately be recovered.
??There are increasing concerns worldwide about the security of oil supply in the future, as well as the effects of global climate change?. Projects that involve CO2 capture linked to EOR projects are unique in being able to address both concerns at the same time?. The capture and use of CO2 contributes to the abatement of carbon emissions and the increase of a more efficient use of energy in upstream operations.
