What began as an experiment in a nine-ounce cup of water has been developed into a full-scale technology that recently became a finalist for a 2019 R&D 100 Award in the mechanical/materials category. Achieving that honor was E-MOP™ — electromagnetic oil spill remediation technology — developed from patents owned by Fermilab. E-MOP uses materials that are environmentally safe, reusable and natural.
“The technology uses electromagnetic pulses and specially timed magnetic fields to produce magnetic forces that move, lift and transport oil,” said Aaron Sauers, Fermilab’s patent and licensing executive. “This provides for an effective and nontoxic method for remediating oil spills both on water and land.”
The U.S. Department of Energy estimates that 1.3 million gallons of oil spill into national waters from vessels and pipelines in a typical year. These spills pose a potentially devastating threat to coastlines, waterways and oceans.
Fermilab licensed the patents used to develop E-MOP technology in 2015 to Natural Science LLC, which was founded by its inventor, Arden Warner, a Fermilab accelerator physicist. E-MOP could also be used industrially to filter and remove clumping substances used in treatment plants and to process and reclaim water associated with fracking and the oil refinery process.
Scientist Arden Warner, left, shows Aaron Sauers, Fermilab licensing and patent executive, the E-MOP system. It consists of solenoidal (doughnut shaped) magnets that are coupled together in groups of six to form a module. Several modules are connected together to form an electromagnetic-boom (e-boom) structure. The system can be made longer or shorter by adding or removing modules to accommodate the situation. Every magnet in the structure is separated from the next by a fixed distance that optimizes the “gradient” effect of the magnetic fields between them. Photo: Reidar Hahn, Fermilab
The technology was sparked by a question that Warner’s wife asked him after the 2010 Deepwater Horizon oil spill in the Gulf of Mexico: “Could we remove oil from water?” It occurred to Warner that electromagnetic forces would probably work.
“Electromagnetic forces always pop into my mind whenever there’s a problem to solve,” he said.
These forces hold electrons in their orbits around atomic nuclei. The electrons interact to form bonds between the elements and molecules that pervade everyday life, from the fires we burn to the chairs we sit on. But engineers can employ these forces in countless devices, including motors, computer hard drives, medical imaging machines and particle accelerators.
The 2010 Gulf oil spill was of special concern to Warner, who grew up in the relatively nearby Caribbean island nation of Barbados. After successfully testing his concept in the water cup, he built a small-scale prototype to evaluate its performance in a large pool.
During the first week of October, his company tested its large-scale prototype in a huge tank at Ohmsett, the National Oil Spill Response Research and Renewable Energy Test Facility in New Jersey. The tank measures 600 feet long, 200 feet wide and holds 2.2 million gallons of ocean water. The tests demonstrated that the E-MOP system was 97.2% efficient in separating oil from water.
“We are getting the oil efficiently off the water without picking up water,” Warner said. “That was our goal, to get it as efficient as we could.”
Spilled oil is first seeded with a small amount of magnetite (less than 0.5% by volume). The system exploits a unique bond that oil forms with magnetite particles at the molecular scale. Magnetite is a naturally occurring magnetic mineral that can be found on most beaches. Heavier than water, the particles sink in the absence of oil. But the presence of oil in water, either on the surface or below, will attract and confine the particles.
“This bond is exploited as the combination of oil and magnetite are rendered magnetic in the presence of magnetic fields,” Warner said. “Viscosity effects are enhanced, the ability to confine, attract and move the spills is increased, and the remediation process is controlled without the use of dispersants and other harmful chemicals and methods.”
Solenoids — coiled wires that produce magnetic fields, together with other magnets — provide the force needed to move the magnetized mixture, collect it and separate the particles for potential reuse and the oil for possible reclamation.
The solenoids form an active electromagnetic boom that fundamentally differs from the passive booms commonly used today. The magnetic boom collects and transports the magnetized mixture within reach of its fields on and below the surface and delivers it to a magnetic ramp.
“This includes mixtures that may be several inches below the surface, as in the case with heavy-oil spills,” Warner said.
R&D Magazine presents the R&D 100 awards annually in recognition of exceptional new products or processes that were developed during the previous year. An international panel of judges selects the awardees based on the technical significance, uniqueness and usefulness of projects and technology from across industry, government and academia.
As spokespersons for the international Deep Underground Neutrino Experiment, we were privileged to meet in October with a delegation in the country of Georgia to discuss a possible agreement between the DUNE collaboration and Georgian Technical University.
DUNE is an international experiment hosted by the U.S. Department of Energy’s Fermilab and is the largest particle physics project in the United States. DUNE researchers will study ubiquitous yet elusive particles called neutrinos, which have the potential to unlock mysteries about the evolution of the universe.
The two of us and DUNE Institutional Board Chair Bob Wilson of Colorado State University discussed potential contributions that scientists and engineers in Georgia could make to the experiment. Georgian Technical University scientists joined the DUNE collaboration in May. The collaboration now comprises more than 1,000 scientists from over 180 institutions in 30-plus countries.
From left: Georgian Technical University Professor Zviadi Tsamalaidze, DUNE Institutional Board Chair Bob Wilson of Colorado State University, DUNE spokesperson Stefan Söldner-Rembold of the University of Manchester, DUNE spokesperson Ed Blucher of the University of Chicago and Georgian Technical University Professor Arsen Khvedelidze meet in October to discuss possible agreement between the DUNE collaboration and Georgian Technical University.
Georgian institutions are active in the world of high-energy physics experiments, collaborating in the ATLAS and CMS experiments at the European laboratory CERN and in the COMET experiment at the Japanese laboratory KEK.
The meeting focused on ways scientists from Georgian Technical University, led by Zviadi Tsamalaidze, could contribute hardware for the DUNE near detector — a particle detector to be located on the Fermilab site. The discussion comes at a time of increased international interest in the near detector, a project that presents a rare opportunity to conduct cutting-edge research on detector technology from design to construction.
The DUNE near detector will feature state-of-the-art technologies to probe the world’s most intense neutrino beam and make precision measurements as neutrinos travel through the detector on their 1,300-kilometer journey to the DUNE far detectors in South Dakota. The DUNE collaboration held a near detector planning workshop at the DESY laboratory in Hamburg, Germany, at the end of October.
In partnering with DUNE, Georgian Technical University would become the newest in a growing number of institutions contributing to the detector of the next big neutrino experiment.
This work is supported by the DOE Office of Science.
Ed Blucher of the University of Chicago and Stefan Söldner-Rembold of the University of Manchester are the DUNE spokespersons.
Photomultiplier tubes dot the 26-ton water tank of ANNIE, the Accelerator Neutrino Neutron Interaction Experiment. Photo: Reidar Hahn, Fermilab
The inside of the ANNIE detector looks like a series of carefully placed Jell-O domes, or perhaps a jeweled Fabergé egg. Its walls are dotted by 137 sensors for detecting packets of light and embrace 26 tons of gadolinium-doped water.
Starting in December, beams of particles called neutrinos will hurtle toward the ANNIE detector at Fermilab, strike atoms inside it and knock off neutrons, shedding light on how neutrinos interact with atoms in a water target and how they scatter.
The physics
Neutrinos are among the most abundant particles in the universe. We know that they have mass and that they oscillate among other neutrino types. But what is this mass? How do neutrinos oscillate? And how do neutrinos interact with nuclei, the core of atoms?
A crucial step in answering these questions is determining the energy of the neutrino that caused a collision. But to do so, physicists only can look at the particles that emerge after the collision took place. It’s like determining the speed of a bowling ball by just looking at the pins it hit.
“Any byproduct of neutrino interactions – neutrons, protons, muons – is important because physicists want to reconstruct the neutrino’s energy,” said Emrah Tiras, ANNIE Phase II detector upgrade manager at Fermilab and postdoctoral researcher at Iowa State University.
In water, neutrinos are typically observed indirectly via the blue Cherenkov light emitted by electrically charged particles that are produced in a neutrino’s interaction with an atomic nucleus. By identifying the locations and times each light photon is detected, physicists can reconstruct the subatomic scene, determining when and where the corresponding charged particle was emitted and in turn learn about the neutrino and interaction that produced the charged particle in the first place.
The problem is that neutrons are not charged particles. They are electrically neutral, meaning they don’t produce Cherenkov light. Because of this, they are hard to detect and easy to go unnoticed.
“Events with charged particles, like protons and muons, are easier to reconstruct, but generally most events include a mixture of charged and neutral particles. Without knowledge of the neutron component in any given event, you can miscalculate the neutrino energy,” Tiras said.
But ANNIE has a solution. The experiment will detect and discriminate between signals produced through two neutrino-nucleus interaction pathways. The first is the transformation of a muon neutrino into a muon. The second is the production of a neutron, which interacts in the water target and produces detectable gamma rays.
Physicists developed and deployed two innovative technologies on ANNIE to address these major uncertainties, count the number of neutrons and determine the probability of neutrino-nucleus interactions.
This test setup is used to characterize large-area picosecond photodetectors for the ANNIE neutrino experiment. Photo: Emrah Tiras
Two technologies
ANNIE will be the first neutrino experiment to employ a new generation of imaging photodetectors.
Large-area picosecond photodetectors, or LAPPDs, detect light, retrace its origins and determine the time the light was emitted. Whereas the more common technology, photomultiplier tubes, might detect “blobs,” or packets, of charge coming from separate photons in a neutrino-nucleus interaction, LAPPDs detect single photon arrivals separated by approximately 60 trillionths of a second. This corresponds to the time it takes light to travel a little over 1.5 centimeters, improving performance over photomultiplier tubes by a factor of 100. ANNIE will detect signals with five LAPPDs and 132 photomultiplier tubes.
Vincent Fischer, postdoctoral researcher at University of California, Davis, stands next to ANNIE’s water filtration system in the experimental hall at Fermilab. Photo: Emrah Tiras
Physicists still needed to tag individual neutrons, and gadolinium-enhanced water is the solution.
Gadolinium, a relatively inexpensive metal used in magnetic resonance imaging and superconductors, forms salts that are dissolvable in water. Adding gadolinium will increase the likelihood of neutron interactions by approximately 150,000 times over pure water alone.
“Once a neutron is captured by gadolinium, a shower of gamma rays is emitted that can then be detected by photomultiplier tubes and LAPPDs,” said Vincent Fischer, postdoctoral researcher at the University of California, Davis, who works on ANNIE. “Adding gadolinium does make cleaning the water more challenging, though.”
Signals in water-based Cherenkov detectors can be absorbed or obstructed by dust, bacteria and other materials, requiring that physicists regularly clean, or purify, the water. But the cleaning systems used in large experiments tag gadolinium, essential to ANNIE, as a contaminant. Fischer and his colleagues at the University of California, Davis, developed a new resin and a new system to circulate and purify the water without filtering out the gadolinium.
Another challenge for Fischer was scheduling when and how much gadolinium should be added to the water.
“If you add gadolinium to the water too soon, rust can form. It’s like ships, which rust faster in seawater than freshwater,” Fischer said.
ANNIE currently holds around 1% of its ultimate gadolinium load, which corresponds to a 10% efficiency in capturing neutrons. The collaboration aims to hit 100% of the planned gadolinium load, or 90% neutron capture efficiency, in the next few weeks.
Today and tomorrow
Together, photomultiplier tubes, LAPPDs and gadolinium-enhanced water will allow ANNIE physicists to accurately identify and count neutrons from neutrino-nucleus interactions. In addition, ANNIE will have a fully operational muon range detector, which analyzes signals originating from muons arising from neutrino-nucleus interactions and escaping the main detector.
The collaboration plans to start taking physics data – detecting neutrons originating from neutrino interactions and measuring the probabilities of neutrino interactions in water – in early December.
“This effort is a culmination of almost eight months of work with, on any given week, four or five collaborators working on detector construction, installation, testing and calibration systems,” said Ashley Back, ANNIE postdoctoral researcher at Iowa State University. “We’re excited to share this achievement with the Fermilab community and the public.”
After the current phase of upgrades and data collection are complete, physicists want to continue using ANNIE as a testbed for new technologies, and the results will be used by larger neutrino experiments to benchmark and constrain their own measurements.
An international collaboration of more than 30 individuals, ANNIE is certainly ready to close the gap on unknowns in neutrino-nucleus interactions, yielding important information for neutrino scientists around the world.
This work is supported by the Department of Energy Office of Science.