Enhanced Oil Recovery (EOR), also known as “tertiary recovery,” is a process for extracting oil that has not already been retrieved through the primary or secondary oil recovery techniques. By using EOR methods, up to an additional 30% of the original crude oil can be extracted from a reservoir. There are many different types of EOR methods, but all involve injecting some type of fluid into the reservoir in order to increase production.One common type of EOR method is called miscible displacement. In this technique, a liquid is injected into the reservoir that can mix with and displace the crude oil. One example of a miscible displacement fluid is carbon dioxide (CO2). When CO2 is injected into an oil field, it dissolves in the crude oils and reduces their viscosity. This makes them easier to extract and increases overall production from the well.Another common type of EOR method is thermal injection. In this technique, heat energy is used to vaporize light hydrocarbons from within the reservoir rock formation. The vapors are then extracted through wells drilled specifically for this purpose. Thermal injection can be used alone or in combination with other methods like CO2 flooding or water flooding.
