Weapons maker finds cheap way to filter sea water
The filter could dramatically cut energy needed to remove salt from water reducing desalinisation costs by 99 percent.
An engineer at Lockheed Martin has found a way to reduce the amount of energy needed to remove salt from seawater, potentially making it vastly cheaper to produce clean water at a time when water scarcity has become a global security issue.
Existing reverse osmosis plants rely on complicated processes that are expensive and energy-intensive to operate.
Lockheed Martin’s Perforene is made from single atom-thick sheets of graphene. Because the sheets are so thin, water flows through them far more easily than through a conventional reverse osmosis filter.
Filters made through the Perforene process would incorporate filtering holes just 100 *nm in diameter—large enough to let water molecules through but small enough to capture dissolved salts. *A nanometer (nm) is a billionth of a meter.
Says John Stetson, the Lockheed engineer credited with the invention of the salt filter: “It looks a bit like chicken wire when viewed under a microscope, but ounce for ounce, its 1000 times stronger than steel.”
Access to steady supplies of clean water is getting more and more difficult in the developing world.
