Research conducted using neutrons at Oak Ridge National Laboratory's (ORNL) High Flux Isotope Reactor (HFIR) is helping scientists explore new ways to extract oil from unconventional reservoirs, thereby strengthening U.S. energy independence.
Dina Hegazy, a researcher at the Colorado School of Mines, is conducting studies using neutrons from HFIR — one of the world's most powerful reactor-based neutron sources. Her research aims to increase oil production from hard-to-extract regions. This work comes at a critical time, as the U.S. Strategic Petroleum Reserve is currently at historically low levels.
The study focuses on improving Enhanced Oil Recovery (EOR) techniques, specifically the effectiveness of carbon dioxide (CO₂) huff-n-puff in unconventional reservoirs. In these reservoirs, oil is tightly bound to the rock, making traditional drilling and extraction methods ineffective and resulting in up to two-thirds of the crude oil being left behind. Compared with other EOR techniques, CO₂ huff-n-puff can significantly improve recovery rates, but operational parameters such as injection pressure and huff-n-puff duration still need optimization. Neutron technology offers a promising solution to these challenges and helps strengthen U.S. energy security.
James Torres, an instrument scientist at HFIR who assisted Hegazy with the experiments, said: "Neutrons allow us to gain insights into these reservoirs that would otherwise be impossible. Neutrons help us visualize fluid movement at a detailed level, enhancing our understanding of the oil recovery process because they interact strongly with light elements such as hydrogen."
Hegazy's research will be used to advance reservoir-scale computer simulations, helping the industry maximize oil extraction using CO₂-enhanced oil recovery (CO₂-EOR) techniques. She will continue to collaborate with the MARS team at HFIR's Multimodal Advanced Radiography Station (MARS) to study nanoscale fluid exchange of carbon dioxide with various fluids in different shale samples. Hegazy said: "Our goal is to observe how carbon dioxide flows through nanopores containing oil. Understanding how nanopore size affects CO₂ flow will allow us to better comprehend how CO₂ displaces oil, thereby improving recovery rates."
In fully oil-saturated shale samples, the images initially appear dark. As carbon dioxide displaces the oil, the images become brighter, creating contrast that allows Hegazy and her team to observe the flow patterns of CO₂. The unique sensitivity of neutrons to light elements enables the team to directly visualize fluid movement within shale samples. At higher pressures, neutrons can penetrate shale samples more effectively. Hegazy expressed that collaborating with the MARS team has been very rewarding and exciting to witness the latest advancements at HFIR.
In addition to HFIR, ORNL operates a second neutron source — the Spallation Neutron Source (SNS). SNS uses an accelerator-based system to produce neutrons and, like HFIR, attracts researchers from around the world to ORNL for neutron scattering studies.
Both SNS and HFIR are user facilities of the U.S. Department of Energy's Office of Science, enabling scientists to utilize the unique properties of neutrons to advance scientific discoveries and address pressing challenges of our time. Neutron scattering is applied in numerous industries, including automotive, aerospace, steel, defense, industrial materials, energy storage, data storage, and biomedicine, to tackle the major scientific challenges of the 21st century.
ORNL's neutron research has driven many discoveries, helping scientists answer major scientific questions and inspiring countless innovations — such as stronger glass for mobile devices, more effective drug therapies, more reliable aircraft and rocket engines, more fuel-efficient cars, improved military armor, and safer, faster-charging, longer-lasting batteries.
