Oil & Gas UK Economic Report 2014

b) Oil Recovery

In simple terms, oil recovery can occur in three phases during the life of a field: i. Primary recovery, driven by the natural pressure in a reservoir. For reservoirs with poor natural pressure, secondary recovery techniques – applying and maintaining pressure artificially – are sometimes used from the outset. ii. Secondary or improved oil recovery (IOR), where artificial pressure is applied to a reservoir, typically in the form of water or gas injected from a production platform. Alternatively, the drilling of additional wells in remote or difficult parts of a reservoir may be used as a means to increase recovery. iii. Tertiary or enhanced oil recovery (EOR), involving more advanced techniques such as those mentioned in Section 5.

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ECONOMIC REPORT 2014