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.
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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.