Imagination is the only limit as academics explore nanotechnology applications for the upstream oil and gas industry, an engineering researcher says. Low oil prices have prompted a number of major service companies to slash research and development (R&D) expenditures, but nanotechnology R&D for oil and gas applications remains underway at a number of universities. One industry expert noted that nanotechnology can help oil and gas companies get more effective performance for fluids already in use, without much more spending required. But lower cost nanotechnology will be key in today’s market.
Recent examples of ongoing nanotechnology – which develop materials and structures by manipulating matter on the atomic or molecular scale – research and development (R&D) in academic settings include the University of Houston’s recent announcement of a new nanotechnology-based solution discovered by UH researchers. This discovery could address two major issues facing the oil and gas industry – boosting the rate of tertiary oil recovery, while safeguarding the underground water resources of communities where unconventional exploration and production takes place.
By using graphene-based Janus amphiphilic nanosheets, UH researchers reported recovering 15.2 percent of oil using their nanofluid solution at the .01 percent concentration. This rate is comparable to chemical methods and approximately three times more efficient than other nanofluids, said Zhifeng Ren, MD Anderson professor of physics, in a June 27 press statement.
Ren noted the solution works in a completely new way: when injected, the solution helps detach the oil from the rock surface. When the graphene-based fluid meets with the brine/oil mixture in the reservoir, the nanosheets in the fluid spontaneously go to the interface, reducing interfacial tension and helping oil flow toward the production well.
Under certain hydrodynamic conditions, the graphene-based fluid forms a strong elastic and recoverable film at the oil and water interface, instead of forming an emulsion. Researchers attribute the difference to the Janus nanoparticles. Nanoparticles are typically either hydrophobic, or water-repelling like oil, or hydrophilic, or water-like. The Janus nanoparticles used in the solution have characteristics of both, and also is strictly amphiphilic.
Existing solutions force producers to choose between a higher nanoparticle concentration – with higher costs – or mixing with polymers or surfactants, which is less expensive. “We anticipate that this work will bring simple nanofluid flooding at low concentration to the stage of oilfield practice, which could result in oil being recovered in a more environmentally friendly and cost-effective manner,” researchers noted in a June 27 paper published in the Proceedings of the National Academy of Sciences. The finding came out of fundamental research, not research at the behest of any oil and gas company, Ren told Rigzone. Field test planning is underway; researchers are looking to partner with an oil and gas company to deploy the technology at full-scale.
Enhanced oil recovery (EOR) will remain a focus area for oil and gas companies as they seek to maximize production. Citing data from the U.S. Department of Energy, UH researchers noted that as much as 75 percent of recoverable oil reserves may be left behind after oil and gas companies produce hydrocarbons that naturally rise to the surface or are pumped out mechanically, followed by a secondary recovery process using water or natural gas injection. Traditional tertiary recovery involves injecting a chemical mix into the well and can recover between 10 percent and 20 percent. However, the large volume of chemicals used in tertiary oil recovery has raised concerns about possible environmental damage.
Graphene-based amphiphilic nanosheets for tertiary oil recovery is one of the recent developments in nanotechnology solutions for the upstream oil and gas industry, Colleen Kennedy, an analyst with Boston-based Lux Research, told Rigzone. Nanotechnology has played a significant role in protective coatings and material applications in the upstream oil and gas industry, but next generation trends for nanotechnology will likely focus on EOR.
Government-funded projects into nanotechnology applications for oil and gas, such as tiny acoustic microseismic emitters for tracking proppants, also continue, Kennedy stated.
Nanotechnology Applications Only Limited by Imagination
Dr. Steven Bryant, chair of material engineering unconventional oil reserves with the University of Calgary’s Schulich School of Engineering, told Rigzone that the only limit to nanotechnology applications for oil and gas was imagination.
Nanomaterials give oil and gas companies new tools to address longstanding issues, such as increasing oil recovery, he said.
“Nanoparticles are small enough to travel through pores in the kinds of sedimentary rock that contain oil and gas,” Bryant explained. “The fact that you can make these particles into other things gives us a chance to have an effect into the reservoir that previously we could only do by injecting chemicals.”
“By putting coatings on nanoparticles that make them both hydrophobic and hydrophilic, nanoparticles can be quite happy in an oil-water interface,” Bryant stated. “Using these types of nanoparticles can allow foams or emulsions to be stabilized with remarkable longevity compared with chemicals and surfactants. Surfactants, on the other hand, are happy at interface, but they come and go.”
New materials not previously available offer opportunities to explore new applications. These materials, and the ability to coat these materials, offers a flexibility in tuning particles that isn’t available with surfactants, Bryant noted. For example, iron oxide particles the size of what can be seen with the naked eye down to the size of sand grains is unremarkable. But in smaller size, it will, in the presence of an oscillating magnetic field, get hot. This allows for one form of energy to be converted into another.
“There’s lots of places where you’d like to be able to apply heat,” Bryant said. “This gives you another way to do that.” Nanoparticles also can endow fluids with magnetic susceptibility; that fluid can be injected into the reservoir. The idea is to create a contrast agent that allows for an operator to see where injected fluid is going. Just like when a patient drinks a barium milkshake before undergoing an X-ray, magnetic fluid can be used in a similar way, Bryant stated. Using nanoparticles as contrast agents can be applied to all types of imaging, from waterfloods to pipelines.
“It’s not the solution to everything, but it provides more flexibility than other solutions,” Bryant commented. Bryant said that the University of Calgary is seeking ways to enhance oil production from unconventionals, including oil sands. Bryant said the university is playing with ideas of how to enhance production from unconventionals, but it’s too early to say whether any of those will pan out.
Nanotechnology Trends in Oil, Gas
In addition to graphene-based amphiphilic nanosheets, other recent developments in nanotechnology applications for oil and gas include nanoparticle tracers and near wellbore treatments, Kennedy said. Nanotechnology not only can enhance production, but it can also make a significant difference in the environmental impact of production on underground water resources. Any improvement to sensors, including nanoparticle tracers for tracing fluid well to well, could definitely have an environment impact, she said.
“Additionally, nanosensors currently in development could significant improve operators understanding of the extent to which proppants are travelling,” Kennedy said. “These technologies are very early stage, but with induced seismic events making headlines in numerous states, there could be a greater push to commercialization.”
”EOR [enhanced oil recovery] has certainly been an area of high interest-polymeric microspheres and nanospheres have been shown to reduce water cut and increase sweep efficiency,” Kennedy stated. “Chemical EOR projects have been limited thus far, but some of these applications could show promise in the future.”
Offshore exploration and production also can benefit from nanotechnology research, such as anti-fouling technology or technology that prevents paraffin build-up. Coatings that target these issues and reduce the need for expensive pipeline replacement are definitely ideal for the offshore environment, Kennedy stated.
The biggest barrier to advancements in nanotechnology for oil and gas could be difficulty associated with gaining field trials for downhole applications, Kennedy stated. Low oil prices are driving operators to focus mainly on cost-reducing technologies with near-term potential and field trial opportunities are limited.
In any technology, driving down cost is key. Kennedy stated that nanoscale robots that can pass through pores in the reservoir or improve resolution maps or reservoirs must be low enough cost to be deployed in large numbers to account for the ‘nanoreporters’ that fail.
“The current environment could eliminate previous business models centered around building multi-million dollar tools with long rental cycles and foster development of lower cost single-use methods of taking downhole measurements,” Kennedy concluded.
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