In April 2010, the Deepwater Horizon oil rig exploded and sank, causing a massive oil spill that lasted for 87 days. It was one of the largest environmental disasters in U.S. history. Forty-seven thousand people worked tirelessly that summer to help protect the beaches, estuaries, and wildlife of the Gulf Coast. Today, scientists and engineers try to learn lessons from the disaster to improve future response efforts.
“Several members of our team were on the Flow Rate Technical Group that established the leakage rate during Deepwater Horizon,” said Jonathan Levine, a National Energy Technology Laboratory (NETL) Postdoctoral Research Associate. He received his Ph.D. in earth and environmental engineering from Columbia University.
Levine’s appointment to the NETL Postdoctoral Research Program is administered by ORAU through the Oak Ridge Institute for Science and Education. The program is intended for recent doctoral graduates to continue developing their research skills and to help them achieve their career goals.
“To understand oil spills you have to understand the way the oil and gas are moving through the ocean. To do this, we study methane bubbles at conditions simulating the deep ocean,” he explained.
A large part of Levine’s research focuses on clathrate hydrates. Clathrate hydrates are the product of gas and water combining in a solid ice-like structure at temperatures above the freezing point of water in the deep ocean.
“During Deepwater Horizon, they put down a containment dome to bring the gas and oil up to the surface, but the gas and water reacted and formed clathrate hydrates, stopping the flow,” he said. “If a spill were ever to happen again, the oil industry needs to have a system to pull up the gas without clathrate hydrates getting in the way. To do that, they need good chemistry and physics data, and that’s what we measure at NETL.”
In addition to studying clathrate hydrates in the context of oil spills, the results are also applicable to the deep sea release of the greenhouse gas methane.
“Most methane seeps out naturally into the ocean over geologic time. As that methane hits permafrost or goes through a shallow cold sea like the North Sea, it gets trapped as clathrate hydrates. But because of global warming changing the temperature of the oceans, these hydrates can melt,” he said.
Levine studies the transport of methane through the ocean as part of a multidisciplinary team consisting of experts in hydrodynamics, thermodynamics, and particle imaging, and includes both experimentalists and modelers. The team uses experimental measurements at NETL’s High-pressure Water Tunnel Facility to determine dissolution rates and rise velocities for bubbles with and without hydrates as well as different gas mixtures.
“The data is incorporated into a model of bubbles moving through the ocean,” explained Levine. “The model is then used to determine how much methane and other gases seeping into the deep ocean will dissolve into the ocean and how much will reach the atmosphere, where it acts as a greenhouse gas.”
“This is a very unique system,” he added. “There are only a handful of groups that study these deep ocean hydrates with all the tools we have here. We've made several new discoveries related to how hydrates form and decompose.”
The program gave Levine the independence he expected as a postdoctoral researcher and advanced his understanding of the chemistry and physics of environmental pollutants, an area of research he still sees himself in 10 years down the road.
Whether in an academic or national lab setting, Levine plans to study how pollutants such as carbon dioxide or methane move through the environment and how science can help mediate their impacts. He knows that there's no shortage of environmental issues, but there is a shortage of solutions.