Typically only 30 per cent of the oil from an oil reservoir can be removed with traditional methods, therefore, there are huge amounts of oil to recover from the present extraction points or even from the extraction points already abandoned.
There are technologies, processes or mechanisms known as: Tertiary Recovery or Enhanced Oil Recovery (with its acronym in English "EOR"), whose application can help to recover between 20 and 50 per cent of the original oil.
Improved Enhanced Oil Recovery methods consist of new technologies that should allow to remove part of this oil that was into the wells (reservoir). Those which appear to have the greatest potential for the final recovery, up to an additional 30‐50%, are called chemical methods that directly attack the problems of capillary entrapment of the crude oil in the porous’ medium.
The use of viscosities Polymers to control the mobility of the injected water have been used for many years in the Enhanced Oil Recovery (EOR). Flooding of polymer for improving volumetric sweep efficiency, reduces the pipeline and improves progress, it has helped many operators to increase oil recovery and to reduce the cost per barrel of recovered oil. These same polymers can be used with surfactants / tensioactives and alkaline agents to increase in some cases the efficiency of scanning in this process.
Floodings polymers can cause a significant increase in oil recovery in comparison with conventional techniques of flood water. A standard system of flooding polymers consists of mixing and injecting polymer for an extended period of time up to approximately 1 / 3 ‐ 1 / 2 of the volume of the pores of the reservoir where it has been injected. This polymer is used by continuous long term injection to boost the oil ahead of it towards production wells (reservoir).
When water is injected within the reserve of oil, there are preferential paths with less resistance, when the oil is very viscous produces small channels, with very low efficiency, while the addition of polymers improves mobility (rate) and increases the movement in the well (reservoir).