Enhanced Oil Recovery Methods
As per GlobalData’s report, enhanced oil recovery (EOR) is slowly becoming an emerging technique to increase oil production globally. It is because mature field production is rapidly declining, and the hydrocarbon discoveries are quite insufficient to meet the high energy demand.
So, considering this shortfall, the EOR oil and gas method helps to fill the gap by extending the fields’ lives and maximizing the number of recovered oil reserves. It also works as an excellent tool for many firms to maintain sufficient production and improve returns on any older investments.
This article covers all the basics of enhanced oil recovery. So, dig in to explore what this phenomenon is and the different methods it includes.
Enhanced Oil Recovery Definition
Also famously called the “territory recovery,” the enhanced oil recovery process extracts oil that other secondary or primary recovery techniques fail to retrieve.
Most primary or secondary recovery techniques work according to the pressure difference between the underground well and the surface.
However, enhanced oil recovery methods are different as they perform by changing the oil’s chemical composition. This alteration makes oil extraction pretty quick and easy.
Differences Between Primary, Secondary and Enhanced Oil Recovery Methods
Here is a detailed explanation of each technique to know why the first two are less effective than the third.
Primary Oil Recovery Techniques
These techniques include the extraction of oil through either hydrocarbons’ natural rise or via lift devices such as pump jacks. However, these methods have a lot of limitations as their performance depends on accessibility. In fact, primary methods can only extract 5 to 15% of oil from a reservoir.
Secondary Recovery Techniques
All secondary recovery techniques inject oil or gas to displace and force the oil to move and come on to the surface. This technique has the potential to recover 30% additional oil from a reservoir.
However, the percentage could be less or more depending on the surrounding rock formations and the oil itself.
Enhanced Oil Recovery
Enhanced oil recovery methods are super effective than the two above. It has three main approaches.
Here is a brief introduction of each:
Gas Injection
This approach is one of the most widely used enhanced oil recovery methods. It is also known as Miscible flooding and involves implementing injection processes to introduce different gases in a particular reservoir.
Gases like carbon dioxide, nitrogen, or natural gases are mixed with the reservoir oil to make its consistency viscous. Meanwhile, the oil is pushed and moved so it can appear on the surface.
Thermal Recovery
This approach aims to increase the mobility of the oil. So, the objective is attained by decreasing the oil’s viscosity or vaporizing most of the oil.
The thermal recovery method uses many processes that help heat the oil and reduce the surface tension. This combination accelerates an easy flow of oil on the surface.
In most cases, steam is added to the reservoir to help increase temperature and produce heat. But in some cases, techniques like fire flooding are used to do this job. Fire flooding helps burn a specific part of the reservoir oil so that the rest of the oil can be adequately heated.
This method is one of America’s most prevalent EOR techniques, which clearly shows its significance.
Chemical Injection
Unfortunately, chemical injection is one of the least popular enhanced oil recovery methods. It involves the injection of chemicals in oil to aid its mobility and decrease surface tension.
Chemicals like caustic and alkaline are injected in the form of diluted solutions to initiate soap production. Thus, it might prove practical to reduce interfacial tension and accelerate the production of oil.
In simple terms, a chemical injection approach uses various chemicals to help the trapped oil escape. It does so by increasing water flooding efficiency and reducing surface tension.
EOR techniques produce amazing results. However, they are expensive and complicated. Thus, it is why only when all the primary and secondary recovery techniques have been properly used and exhausted, the EOR oil and gas methods are employed.
If factors like high oil prices are considered, EOR techniques may fail to prove economical. So in such cases, the non-extracted gas and oil might be left in their respected reservoir as extracting them may not be profitable at all.
How Are the EOR Techniques Used Today
Many petroleum companies find lots of potential in the EOR techniques. It is because they can increase the wells’ life in probable or proven oil fields.
Probable oil fields are those with a more than 50% chance of recovering petroleum. At the same time, proven reserves are those that contain more than a 90% chance that oil will quickly be recovered.
That being said, we can’t deny that enhanced oil recovery methods can become quite dangerous for the environment sometimes. For instance, many harmful substances can seep into the ground during chemical injection techniques and harm the water. Since this dilemma is a significant threat, engineers need to work on new ways to reduce this risk.
The Future of EOR Oil and Gas Techniques
If economical, the enhanced oil recovery methods can help provide lower or equivalent cost barrels compared to many emerging greenfield developments. As a result, EOR can become an imperative technology to play a crucial role in the worldwide supply of gas and oil.
However, this approach alone cannot do wonders. It requires the consistent support of advanced technology to monitor and assess the amount of oil present in these times. For instance, machines that can measure the oil’s viscosity, density, fluctuations, and behavior are vital to successful enhanced oil recovery processes.
Final Words
EOR technologies are the future of oil extraction and production. With fewer new discoveries, these methods are becoming much better options than primary and secondary recovery techniques.
However, since enhanced oil recovery methods are costly, they are still not being used as per their full potential. So, this is why engineers and oil companies should come together and make efforts to make the enhanced oil recovery method accessible to all economies. Only then will companies be able to meet the increasing demand and save the world from any possible oil scarcity.