Enhanced Oil Recovery (EOR)                                                                                      

 Image courtesy of: Flickr

EOR is the process of CO2 injected into depleted oil reservoirs to enhance oil recovery from the reservoir and is critical to deploying early CCS projects because it provides revenue to offset costs. EOR is an established industry that has been in operation in Texas for decades.      

 

EOR injects CO2 deep underground in order to force out hard-to-reach oil.  The CO2 that remains underground from EOR is permanently locked deep underground.  

 

For three decades the U.S. petroleum industry has successfully injected 35 million metric tons of CO2 -- the equivalent of eight coal fired power plants -- into deep rock formations. 

 

  • The town of Seminole in West Texas sits over one of the country’s oldest and largest EOR facilities, where oil recovery operations are currently injecting one million tons per year, with no harmful subsequent release of CO2. 
  • In Saskatchewan Canada, CO2 from a coal gasification plant in ND totaling approximately 13 mmt has been injected at the Weyburn-Midale field for EOR.
  •  In the West Texas SACROC EOR field it is estimated that approximately 175 million tons has been injected and sequestered over the past 37 years.
  • In the Texas Permian Basin alone, approximately 1 billion metric tons have been injected.

 

 

Because CO2 is an expensive commodity, CO2 is separated from the produced oil and recycled and re-injected into the producing formation. During each cycle roughly half of the CO2 is left behind in the reservoir formation by capillary trapping and solution trapping.  As a result, purchased CO2 becomes progressively locked into the reservoir formation until it approaches 100 percent.  Because EOR is a closed system, very little  is released as fugitive emissions—a small amount may remain in the oil or gas produced and CO2 could be temporarily flared and lost during a shutdown.  That amount has not typically been reported publically but by some estimates may be on the order of one percent.                                                                                     

Other industries have similar long-term experience with underground storage of fluids. For instance, natural gas has been safely and routinely in deep geologic formations for 80 years, in some cases under major urban areas. The United States disposes of more fluids by deep well injection every year than the quantity of CO2 emitted by the nation’s power plants.             

 



Fact

CATF is working to

  • Establish carbon capture and storage as a major global industry.
  • Create a new generation of technologies and institutions capable of removing carbon dioxide that has already been released to the atmosphere.
  • Work directly with industry on getting more federal and state money to support these projects. 
  • Communicate with national and international news outlets, seeking to be seen as an honest arbitrator in coal and climate factual disagreements