Elevating Oil Extraction: A Deep Dive into Enhanced Oil Recovery (EOR)


Unlock the mysteries of Enhanced Oil Recovery (EOR) with this comprehensive guide. Dive into the principles, techniques, economic aspects, environmental considerations, and explore answers to frequently asked questions. Gain a deeper understanding of how EOR impacts the petroleum industry and its vital role in maximizing oil extraction.

Introduction to enhanced oil recovery (EOR)

Enhanced Oil Recovery (EOR), often referred to as “tertiary recovery,” represents the pinnacle of oil extraction techniques. While primary and secondary recovery methods rely on natural reservoir pressure or the injection of water to displace oil, EOR takes a more sophisticated approach. It transforms the chemical composition of oil to make it easier to extract.

Understanding enhanced oil recovery

EOR’s primary goal is to tap into oil reserves that are otherwise out of reach using traditional methods. By altering the properties of the oil itself, EOR unlocks reservoirs that were once considered too challenging or uneconomical to exploit.

How enhanced oil recovery works

EOR techniques are intricate and are typically employed when primary and secondary recovery methods have reached their limits. The feasibility of EOR hinges on oil prices, as it can be a costly endeavor. In favorable market conditions, EOR becomes a viable strategy to recover the remaining oil that would otherwise stay underground.

The three main types of EOR techniques

EOR encompasses three primary techniques, each with its own set of unique features and considerations:

Gas injection

Gas injection involves forcefully injecting various gases into the well, pushing oil to the surface and reducing its viscosity. Carbon dioxide (CO2) is commonly used for this purpose. Recent advances enable the transport of CO2 in the form of foams and gels, making it more versatile. However, there are concerns about its environmental impact.

Thermal methods

Thermal EOR techniques use steam to heat the oil, making it less viscous and easier to extract. Fire flooding, which ignites controlled fires around the reservoir periphery, can also be employed. While effective, these methods can be resource-intensive.

Chemical injection

Chemical EOR involves injecting polymers and other substances into the reservoir to reduce viscosity and increase pressure. These techniques can be highly effective but are often costly.

Utilizing enhanced oil recovery methods

EOR offers promise to petroleum companies and scientists seeking to prolong well productivity, especially in proven or probable oil fields. Proven reserves have a greater than 90% chance of yielding oil, while probable reserves have more than a 50% likelihood of recovery.

Pros and cons of enhanced oil recovery


Here is a list of the benefits and drawbacks associated with enhanced oil recovery (EOR) techniques.


  • Unlocking previously unrecoverable oil reserves
  • Prolonging the economic life of wells in proven oil fields
  • Potential for enhanced environmental friendliness through emerging technologies


  • Highly complex and costly techniques
  • Economic viability influenced by oil prices
  • Potential for negative environmental impacts, including groundwater contamination

Frequently asked questions

Can EOR techniques recover all the oil in a reservoir?

No, EOR methods typically recover a fraction of the original oil in place. The percentage varies based on reservoir characteristics and the specific EOR technique used.

Are there any eco-friendly EOR alternatives?

Emerging technologies like plasma pulsing offer more environmentally friendly options. Plasma pulsing involves low-energy emissions to lower oil viscosity, without injecting gases or chemicals into the ground, potentially reducing environmental harm.

What factors influence the choice of EOR technique?

The selection of an EOR technique depends on factors such as reservoir properties, cost, and environmental considerations. Companies conduct detailed assessments to determine the most suitable method.

Is EOR economically viable during low oil price periods?

EOR’s economic viability is closely tied to oil prices. During periods of low oil prices, the costs of EOR may outweigh potential profits, making it less economically attractive.

Key takeaways

  • Enhanced Oil Recovery (EOR) is the tertiary phase of oil recovery, targeting previously untapped reserves.
  • The feasibility of EOR depends on oil prices, with higher prices making it more economically attractive.
  • Emerging technologies like plasma pulsing offer eco-friendly alternatives to traditional EOR methods.
View Article Sources
  1. Improved oil recovery and enhanced oil recovery methods – Pennsylvania State University
  2. Enhanced oil recovery – University of Texas at Austin
  3. Enhanced oil recovery techniques – Stanford University
  4. Enhanced oil recovery – U.S. Department of Energy
  5. What companies are in the basic industries field? – SuperMoney