Research efforts have yielded an array of tools to enable recovery of high volumes of hydrocarbons from targeted reservoirs that would have been nonproducible even in the relatively recent past.
Even so, the U.S. Department of Energy (DOE) reported in 2006 that about 67 percent of all U.S. oil remains in place after initial production. The agency estimated that possibly 25 percent of this oil can be recovered using conventional recovery techniques.
So, you ask, what’s an operator to do to find and recover all that leftover crude?
Research efforts funded by the Advanced Energy Consortium (AEC), which opened for business last year under the management of the Bureau of Economic Geology at the University of Texas at Austin, may ultimately provide the answer.
The research objective of the AEC – which is comprised of oil industry leaders – is to locate and extract the billions of barrels of potentially available petroleum supply that remain in place following conventional recovery, according to consortium senior manager Sean Murphy.
Past AAPG president Scott Tinker serves as director of the organization.
To reach this lofty goal, the AEC program is funding scientific research in the infinitesimally small and relatively unexplored “nanorealm,” which previously had not been examined seriously by geoscientists or petroleum engineers.
According to John Ullo, senior manager at Schlumberger Doll Research Center in Boston: “… with the depletion of conventional hydrocarbon resources and the need to explore and recover from unconventional sources, the industry now must understand where much of the remaining hydrocarbons are trapped – at the nano scale.
“This could very well be the beginning of a new field of geosciences (called) “nano-petrophysics,” Ullo noted.
The AEC is focused specifically on the application of nano-scale technologies to the exploration and production of oil and gas, Murphy noted. He explained that nanotechnology is the field of science defined by the nanometer, noting that one nanometer is the equivalent of one-billionth of a meter.
The extremely harsh downhole environments characteristic of many oil reservoirs are a particular challenge to nanotechnology application. Given the often excessive temperatures, pressures and corrosive fluids, conventional microelectronic sensors could not survive, much less operate and communicate.
This evolving technology is about as esoteric as it gets.
“The primary goal of the research consortium is to develop subsurface micro- and nano-sensors that can be injected into oil and gas wellbores,” Murphy said. “By virtue of their very small size, these sensors would migrate out of the wellbores and into and through pores of the surrounding geological structure to collect data about the physical and chemical characteristics of hydrocarbon reservoirs,” he said, “thereby helping to ‘illuminate’ these reservoirs in terms of additional information.
“The data collected could ultimately enable a more efficient exploitation of hydrocarbon resources,” he added.
This could be particularly beneficial for enhanced oil recovery (EOR) applications.
“In general we see nanotech as being the one big quantum step that companies can take in getting additional information about a reservoir, and then also in exploiting and enhancing recovery,” said David Zornes, technology adviser with the reservoir performance group at ConocoPhillips.
“The use of nanotech to deliver EOR chemicals is one big area that has a big future for companies,” Zornes said, “in that we can go after the 30-to-50 percent remaining oil that is located in typical reservoirs after they are produced via primary (methods) and then with a secondary waterflood.”
The roster of AEC members currently includes industry heavyweights BP America, Baker Hughes, ConocoPhillips, Halliburton Energy Services, Marathon Oil, Occidental Oil and Gas, Schlumberger, Shell and Total.
Rice University’s Smalley Institute for Nanoscale Science and Technology (SINST) is a key technical partner, and a team of SINST professors already has built and is lab-testing hydrophilic carbon clusters informally dubbed nano-reporters.
These nano-scale entities contain signaling molecules designed to detect oil, water, certain chemicals, etc. in the reservoir. Upon recovery from the reservoir, these nano-reporters will reveal significant information about what they saw, according to Rice professor and project principal investigator Jim Tour, an AAPG member. More Info
A list of promising technologies that conceivably can be employed to better characterize reservoirs and aid in recovery efforts includes a variety of nanoallomorphs of carbon, magnetic nanoparticles, chemotaxic micro- and nanotube structures, and nanoexplosive materials, according to Murphy.
He noted the consortium is convinced that building on ongoing research in smart dust, medical imaging and nanofluidics fields could lead to breakthroughs in “illuminating” the hydrocarbon reservoir.
The AEC currently is funding 22 individual research contracts, and Murphy categorized the projects under way:
Passive sensors (molecular-based such at Tour’s nano-reporters).
Active sensors (traditional electronics-based sensors that must be shrunk to size).
Studies advancing fundamental knowledge.
Murphy noted that new advances in technology being actively pursued by the consortium could enable autonomous, self-powered sensors that communicate parametric data that identify bypassed oil and gas.