The Rocky Mountain region of the US is to take advantage of newly available CO2 sources for enhanced oil recovery (EOR) purposes, such is the growing popularity of this gas application.

In the US alone, CO2 injection has accounted for the recovery of around 1.5 billion bbl of oil and CO2 sales to EOR projects are thought to have reached an estimated 3 bcfd in 2008 - with about 83% of this derived from CO2 source fields.

So popular is CO2 injection for EOR purposes, that successful projects in the Permian basin of West Texas and beyond are held up as examples of the promise of this application. However, CO2 availability has been one factor limiting its use.

With new sources of CO2 set to come to the fore soon though, the northern Rocky Mountain region of the US may see more EOR projects, according to a report by the Oil & Gas Journal.

Two potential new sources for CO2 in Wyoming are a proposed underground coal gasification (UCG) project in the Powder River basin and a coal gasification and liquefaction project near Medicine Bow.

Another CO2 source that will become available in 2010 is the completion of a $72m expansion at ExxonMobil’s Shute Creek gas processing plant.

The expansion includes installation of 23,000 hp of CO2 compression for increasing CO2 sales by 110 MMcfd from the current 230 MMcfd. The Shute Creek plant has a 700 MMcfd of gas processing capacity and receives gas from LaBarge field in Sublette, County, Wyoming.

The composition of the gas from La Barge is thought to be around 66% CO2, 21% methane, 7% nitrogen, 5% hydrogen sulfide, and 0.6% helium.

According to the Oil & Gas Journal, La Barge is also the site of a $100m pilot for demonstrating ExxonMobil’s controlled freeze zone, single-step process for CO2 separation. The company plans to start up the pilot in 2010 and expects it to be a lower cost process that may make carbon capture and sequestration a more practical option for CO2 separated from natural gas.