Blog

Oil extraction has been evolving for years. The latest method of enhanced oil recovery is taking oil extraction to a new level.

So what makes EOR methods of oil extraction better than traditional methods like drilling?

Enhanced oil recovery techniques remove a much higher percentage of oil from the earth, bringing down cost while increasing efficiency.

Primary and Secondary Oil Recovery

Primary drilling methods either tap oil that naturally rises, or can easily be pumped to the surface.

US Department of Energy studies show that primary drilling methods extract around 10 percent of a well’s oil reserves.

Secondary oil recovery, like fracking, can retrieve up to 30 percent more oil from an existing well by pumping water to push trapped oil to the surface.

What is Enhanced Oil Recovery?

EOR methods to oil extraction include thermal recovery, chemical injection, and gas injection to enable even further yield.

Thermal Injection

Thermal injection, like the use of steam, heats oil within a reservoir to reduce its viscosity and ease the release of oil and make it flow to the surface.

Gas Injection

Gas injection uses carbon dioxide, nitrogen, or natural gas to mix with trapped oil to make it more viscous. The gas also pushes the oil to the surface.

Chemical Injection

Chemical injections lower the oil’s surface tension, letting it flow from trapped pockets and is then brought to the surface by water flooding. Chemical injection is the least favored method due to the need for secondary water pumping to push oil to the surface.

Why Enhanced Oil Recovery is More Efficient for Oil Recovery

Enhanced oil recovery employs methods to alter the state of trapped oil in order to extract it, instead of just trying to force it out the ground by water pressure.

Current EOR methods to oil extraction can recover up to 60 percent of the oil left in a reservoir after traditional extraction methods have been employed. This extra source of fuel is bolstering global oil reserves while reducing expenditure.

Enhanced oil recovery techniques can extract millions of more barrels of oil from wells that have already been through the primary and secondary recovery methods.

The cost to bring the first barrel of oil from a new field is astronomical, especially with locations that are difficult to reach like deep sea reserves. The ability to use enhanced oil recovery on already tapped wells is more environmentally friendly and reduces cost.

The Future of Domestic Oil Production

As the earth’s oil reserves continue to become depleted, the need for extensive research and development into improved EOR methods will increase.

Oil recovery companies, like Nakasawa, incorporate engineering and investment in new enhanced oil recovery technologies that are increasing the yield of new and existing oil fields while cutting overall costs.

Energy companies understand the importance of gaining full recovery from existing oil reserve fields, in order to maintain sufficient oil levels to sustain global demand.

Different industries have solely relied on oil to drive the wheels of the various machinery. The demand for oil has increased. In 2018, the daily consumption of oil has reached 99 million barrels. So how can oil producers meet the increasing demand?

Oil production process consists of three phases: primary, secondary, and tertiary phases. But even after the last phase, a lot of oil still remains in the well (about 60%-80%). That’s where enhanced oil recovery comes to play. The process generates an additional 30%-40% of the original oil in place.

So, what is enhanced oil recovery? This is a thermal process that increases the quantity of crude oil extracted from a reservoir by the addition of substances that were previously not found in the well.

Understanding Thermal EOR

The thermal recovery process is when the well is heated at controlled temperatures to reduce crude-oil viscosity. It is an effective method in oil production, accounting for over half of the total EOR production. Thermal EOR can be done through the following processes:

· Steam injection

The injection of heated steam to an oil well during the formation stage to lower its viscosity while vaporizing some of it to boost the mobility. It is commonly used in shallow oil reservoirs.

· In-Situ combustion

Injecting a stream of gas containing oxygen into an oil well. The process utilizes a special heater that causes ignition in the reservoir, thus creating fire. As the fire continues it produces a mixture of hot gases that reduce viscosity, causing the oil to flow toward a production well.

The Steam Injection Process

Steam injection processes have been used by oil production companies since the 60s and effective when used in shallow reservoirs. The injected steam not only helps in increasing the mobility of oil but also creates the perfect permeability conditions and enables the oil to seep through the well and into a collection well. The vaporized gas produces oil with better quality once it has condensed in a collection reservoir.

Steam injection can be done through cyclic thermal recovery or steam flooding. During the cyclic oil recovery method, steam is introduced in a well and then used again in production. Initially, a stream of hot moisture is pushed into the well. The process then enters the soak phaser the oil is allowed to soak in steam for a few days. Lastly, the resulting oil is produced in the exact well.

In steam flooding, heated steam produced at ground level is injected in an oil reservoir using special shafts, evenly distributed across the well. The steam then causes the heavy oil to loosen causing it to flow easily. The process also results in the vaporization of oil, which separates from light components. The gaseous oil then collects in an oil bank as cleaner oil.

The Role of Carbon Dioxide (CO2) in Enhanced Oil Recovery

Originally, oil flows naturally from a newly discovered oil reservoir. But as time elapses, the pressure gradient lowers, and the oil hardly makes it to the subsurface. CO2 is then injected as an EOR agent to increase pressure and push the oil toward the surface.

The CO2 along with other agents mix partially with the oil, causing some expansion, which significantly reduces viscosity. It is an alternative EOR method in impermeable wells where water flooding is economically inviable. Besides, using carbon dioxide to recover more hydrocarbons can significantly reduce C02 levels in the environment.

Enhanced oil recovery (or EOR) – also known as tertiary recovery – is the extraction of crude oil from an oil field that cannot otherwise be extracted, and the process can extract 30 to 60-percent or more of a reservoir’s oil compared to 20 to 40-percent when utilizing primary and secondary recovery methods. According to the U.S. Department of Energy, three major techniques for EOR encompass thermal, gas injection and chemical injection, with more advanced (and speculative) EOR techniques referred to as quaternary recovery.

But as of late, there has been talk of the ways EOR can benefit the economy, as well as its employability benefits, much of it having to do with prevailing oil prices. Indeed, adding oil recovery methods increases oil’s costs, yet the increased extraction of oil can be seen as an economic benefit, with the revenue depending on the aforementioned prevailing prices. These prevailing prices depend on a myriad of factors, but also determine the economic suitability of any procedure; important to note here is that more procedures and additional expensive procedures are more economically viable at higher prices.

Benefitting the Economy: A Closer Look

Analysts believe that the use of captured, anthropogenic carbon dioxide – derived from the exploitation of lignite coal reserves – to drive electric power generation and support EOR from existing and future oil and gas wells delivers a multifaceted solution to the challenges faced by America’s energy, environmental and economic sectors. Beyond the shadow of a doubt, coal and oil resources are finite, and the U.S. in particular is finding itself in a strong position to leverage such traditional energy sources to supply future power demands, all while other sources are being developed or otherwise explored.

Let’s now get to the heart of the matter: Does increasing enhanced oil recovery actually stimulate the economy? Absolutely. According to reports such as the factsheet put forth by the Center for Climate and Energy Solutions, EOR will create and preserve high-quality vocations and enable states and local governments to realize additional revenue, reduce oil imports and trade imbalances and inject millions of dollars into local businesses.

Here are some additional statistics that support these findings:

• Expanded EOR could provide, according to recent estimates by the U.S. Carbon Sequestration Council, up to $12 trillion – equal to about 80-percent of the U.S. national debt – in economic benefits to the country over the next three decades.
• A report by the University of Texas Bureau of Economic Geology’s (TBEG) Gulf Coast Carbon Center quantifies the total economic activity of oil production for Texas to be 2.9 times the value of the oil produced; put simply, almost two dollars of additional economic activity is generated for every dollar of oil produced.
• Advanced Resources International (ARI) estimates that an increase in oil production from EOR could reduce net crude oil imports by half – while providing up to $210 billion in increased federal and state revenues by 2030.

The Job Market Factor

Because workers will be needed across the full EOR value chain, increasing EOR will definitely create jobs. From building and operating CO2 capture systems at power plants and industrial facilities to constructing new pipeline networks, transporting CO2 and retrofitting to give new life to existing oil fields, the future looks bright for the EOR-working relationship.

It is believed that the Kemper County Integrated Gasification Combined Cycle project in Mississippi will create around 300 permanent jobs from power plant and supply chain operators, while a proposed Midwest pipeline – which would transport manmade CO2 captured from coal gasification plants in Illinois, Kentucky and Indiana to the Gulf Coast – could create over 3,500 local jobs over a four-year construction period and over 2,000 jobs from indirect economic activity.

Oil reserves are a valuable asset that simply makes landowners super rich. However, the oil that they yield serves to power the national economy and benefit millions. Owing to the fact that most oil wells from the past were harnessed only up to 25 percent of their potential, owners of oil rights desire to sell their rights only to wells that can harness the entire potential of their reserves. Oil firms also go through a lot of trouble in ensuring that they drain oil reserves dry. They must maximize on the technical and legal investments that they make in setting up oil wells. In fact, their representatives must explain the thoroughness of their process when pitching to rights owners. Therefore, they must understand enhanced oil recovery comprehensively and represent wells that place emphasis on investing in EOR technologies.

Enhanced Oil Recovery

The US Department of Energy reports that primary and secondary oil recovery phases account for only 25 percent of oil production. Whereas enhanced oil technology can ultimately replace the two oil recovery methods and harness 100 percent of a reserve’s potential, it mostly comes as a tertiary measure. That is because the primary and secondary oil recovery methods are largely inexpensive compared to EOR well costs. This method works by increasing pressure in the reserves for enhanced displacement.

The Three Types

This comprehensive method of oil recovery is practiced in three different designs:

• Chemical flooding.
• Gas injection.
• Thermal recovery.

It is important to note that oil wells do no employ the three designs interchangeably. Careful and detailed research must be done regarding the oil reserve and how it is structured geographically. The implications affect the economic cost efficiency and determine which, if any, of the designs, should be deployed to increase recovery.

Thermal Recovery

Sometimes, the oil becomes too viscous after significant recovery. That affects displacement and leads to reduced recovery. The thermal enhanced oil recovery introduces heat inside of the reservoir by applying steam. The increased heat ultimately thins the oil and enhances the displacement needed for optimal recovery. Thermal enhanced oil recovery was first applied in 1961 in Venezuela. Its productivity and cost-efficiency led to its popularity. It accounts for about 54 percent of the oil harnessed through enhanced oil recovery.

Gas Injection

This method is great because it operates with a duality of physical science. It involves technicians injecting natural gases into a reservoir. Nitrogen and carbon dioxide are the most favorable natural gases because they absorb into the oil most easily. Apart from reducing the viscosity of the oil, either of the gases is injected under high pressure to enhance displacement. The two gases often expand robustly when they can’t dissolve into the raw oil. That ultimately increases recovery.

Industrial processes are profusely producing carbon-dioxide and polluting the ozone layer. That is the reason why it is increasingly gaining favor over hydrogen in the gas injection. Ultimately, environmentalists are championing for oil wells to but waste carbon-dioxide from firms that are most responsible for its pollution. The United States developed this technology, and it enjoys heavy environmental and economic benefits from using the gas pollutant to increase its energy production.

Chemical Injection

This method is only great for increasing the efficiency of flooding techniques. The method is rarely used, and it used where some oil reserves are trapped. During the flooding, scientists introduce chemicals that reduce the surface tension of the oil. Other surfactants may be used as well. The oil becomes less viscous and that improves the rate of its displacement. The chemicals injected are polymers.

Parting Shot

All the parties that are involved in the exploitation of oil rights deserve to reap the full benefits of a reserve. That means that recovery should be enhanced and harnessed up to the full potential of a reserve. However, some companies do not have the equipment or expertise to harness the entire potential of a reserve. Some companies use multiple tertiary oil recovery methods to be completely thorough. Do not enter into agreements with companies that are crazed with the returns of recovering less than 40 percent of your oil reserve. That will only make it exceedingly expensive for another company to set up another oil well. You should always inquire about the assets and methods used by oil firms in their recovery processes.

International Petroleum Technology Conference Brief:

Founded in 2005, it is the flagship multidisciplinary event in the Eastern Hemisphere.

IPTC is sponsored by four industry organizations and societies, the American Association of Petroleum Geologists (AAPG); the European Association of Geoscientists and Engineers (EAGE); the Society of Exploration Geophysicists (SEG); and the Society of Petroleum Engineers (SPE).

IPTC is focused on the dissemination of new and current technology, best practices and multi-disciplinary activities designed to emphasize the importance of the value chain and maximizing asset value.

For more information visit the IPTC website.

Nakasawa Mining and Energy Ltd., (“Nakasawa”), held an unveiling ceremony in the final quarter of 2017 at their China-based manufacturing facilities. Nakasawa’s flagship (EOR) Enhanced Oil Recovery Steam Generator System, the NK-30TTS. This unveiling is a culmination of efforts that have spanned over 12 months since the project officially commenced in early 2016.

The NK-30TTS is the latest from Nakasawa in their line of EOR Steam Generators, the 25MMBTU/h steam generator meets and exceeds all industry standard requisites for pressure vessels and power boilers, and has been presented with the ASME BPVC (U), and (S) certification stamps of approval. The NK-30 thermal technology system can be acquired individually but, are usually coupled with a water treatment plant trailer, and office trailer with a fully furnished workspace for the operators of the equipment. With the NK-30TTS unveiling an exhibition of Nakasawa’s China-based super-factory production line, capable of fabricating 30 units of equipment per fiscal quarter; Nakasawa intends to create positive momentum in the Latin American upstream oil and gas industry.

NK-30TTS (Design 1800 PSIG) Data:

• Total Duty per Heater: 25 MMBTU/h
• Heater Section: Natural Gas/Diesel
• Service: Vapor
• Fluid Name: Wate
• Mass Flow Rate: lb/h 25,000
• Volumetric Flow Rate: gpm 50

Inlet Conditions:

• Temperature: °F 90
• Pressure: psig 2,065
• Liquid Flow: lb/h 25,000
• Vapor Flow: lb/h 0

Outlet Conditions:

• Temperature: °F 623 F @ 1815 psig
• Pressure: psig 1,815
• Liquid Flow: lb/h 4,500
• Vapor Flow: lb/h 20,500
• Steam Quality: 82

About Nakasawa Mining & Energy Ltd.

Nakasawa designs, engineers, constructs and delivers heavy equipment to global markets for enhanced oil recovery in heavy oil plays. The company is comprised of four business divisions; design and engineering, manufacturing, installations, and the start-up and commissioning of facilities and operating units. Headquartered in Panama City, Panama the company holds additional offices in Miami, Florida and in Shangdong, China.