By David Alexander
WASHINGTON (Reuters) - Defense contractor Lockheed Martin Corp is developing filters using nanotechnology to help solve a problem facing the booming U.S. oil and gas industry: 18 billion gallons of wastewater each year.
Lockheed's patented Perforene is a one-atom thick membrane of graphene, made of pure carbon. The sheets can be produced with precisely sized holes as small as 1 nanometer, or a billionth of a meter, and the company's goal is to eventually use it for desalination.
In the meantime, Lockheed is looking at other commercial applications, including the oil and gas industry and medical care, which are not as technically challenging, Daniel Heller, Lockheed vice president for sustainability technologies, said in an interview this week.
"Ultimately desalinization is the Holy Grail," Heller said.
Other industries had showed interest in the technology, he said. "And a lot of them had less stringent requirements in terms of the quality of the graphene and hole sizes."
Lockheed is working under contract with two firms in the oil and gas industry to assess the feasibility of using Perforene filters to clean drilling wastewater. The aim is not to eliminate all the contaminants but the worst of them, making the problem easier to deal with, Heller said.
"Whereas with desalinization we had to get to 1 nanometer hole sizes, I think we're in the 50 to 100 (nanometer) region, which is actually a simpler problem for us," he said.
The U.S. Environmental Protection Agency estimates 10 barrels of wastewater are produced for every barrel of oil recovered. The American Petroleum Institute estimates the industry produces 18 billion barrels of waste fluids annually.
Heller said commercialization of Perforene filters could begin in the next five years, possibly with some sort of medical device that would only require small amounts.
Finding a way to produce graphene with nanometer-sized holes on a commercial scale for desalination would probably take five or more years, he said. The company has tested it only on a small scale, but the results were promising.
"Desalinization at the municipal level is really energy intensive because you've got to pump the seawater through layers and layers of filters that aren't really permeable."
"With our technology, we've already ... done it. We can free flow salt water over our Perforene and it filters out the salt," Heller said. "Now we just have to figure out how to do it at scale and make it economically viable."
(Reporting by David Alexander; Editing by David Storey and Lisa Shumaker)