Here is a more informative desciption of the EOR precess from Madison Williams report 4 Nov 2010 Page 17.
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"The miscible process begins with the placement of CO2 under such pressure and temperature that it becomes a supercritical fluid, one that maintains the properties of a gas while having the density of a liquid. The supercritical CO2 is then injected into the reservoir where it will mix thoroughly with the oil such that the interfacial tension between the two substances effectively disappears. The CO2 also improves oil recovery by dissolving in, swelling, and reducing the viscosity of the oil. Additional well drilling and pattern realignment also help to contact bypassed oil. Together, these actions enable portions of the stranded oil to become mobile, connected to a wellbore, and thus recoverable. CO2 can also be injected as part of an immiscible process, in which the two fluids remain distinctly separated. Sufficiently deep formations with lighter (higher gravity) oil are often miscible CO2-EOR candidates, whereas a portion of the shallower oil reservoirs with heavier (lower gravity) oil may be immiscible CO2-EOR candidates. The use of CO2 to enhance oil recovery is neither a new nor an exotic technology. As of March 2010, there were 105 CO2-EOR projects providing over 250,000 barrels per day of incremental oil production in the United States. 1.5 billion barrels have been produced in the U.S. since 1986 using this method, and another 1 billion barrels are booked as proven reserves. It is ironic then, given the widespread concerns about CO2 emissions, that the single biggest impediment to incremental EOR production is the availability of CO2. Traditionally, EOR projects have used naturally occurring sources of CO2 for their injection needs. These sources are increasingly rare, however, and oil companies have begun searching for anthropogenic sources to supply future operations. Thus a tremendous opportunity exists for companies like Linc with access to consistent and clean sources of CO2."/
