A New Way To Desalinate — Government Tested, Real-World Approved
By Patrick Curran, CEO and founder, Atlantis Technologies
Developed by the Department of Defense, capacitive deionization (CDI) removes salt from water, while conventional methods remove water from salt.
What is easier, removing 96.5 parts of something from 3.5 parts of something else or removing 3.5 parts of something from 96.5 parts of something else? All else being equal, of course it is easier to remove the lesser component from the larger. But that is not how most water desalination technologies work today. Reverse osmosis (RO) and vacuum distillation (VD) all work by removing the water from the salt water. So, how can you remove salt from water?
Removing ions from solution with an electric field is a well-known method to desalinate water, and electrodialysis is a popular example. Because ions are disassociated in solution (Na+ separate from Cl-), they can move independently of one another and can be pulled towards an oppositely charged plate. Removing ions from solution as it is done with electrodialysis (ED) can be a much easier way to desalinate water versus the standard reverse osmosis or brine concentrator method of removing water from the salt water.
Image credit: "Norge, kjempers fødeland II," © 2011 tjodolv, used under an Attribution-ShareAlike 2.0 Generic license: http://creativecommons.org/licenses/by-sa/2.0/