Researchers from MIT have created portable desalination units that can effectively remove dust, particles and salts to purify water
The desalination units are roughly the size of a suitcase, require less energy to operate than a cellphone charger and can be powered by a portable solar panel. As per MIT’s educational report, it generates drinking water fresh enough to exceed WHO quality standards.
This device uses electrical power to clear particles from drinking water. Senior author Jongyoon Han, professor of electrical engineering, member of the Research Laboratory of Electronics (RLE), and computer science and biological engineering, has explained how this was the culmination of a 10-year journey his organisation has undertaken. Years and years of hard work on the physics behind the individual desalination processes, but driving these advances into the box and experimenting with the unit was a gratifying experience for their team. Other team members include first author Jungyo Yoon, a research scientist in REL, SungKu Kang, Eric Brack and Hyukjin J. Kwon.
The machine was first field-tested at Boston’s Carson Beach, and to unanimous delight, it was successful in its first run. The device was placed near the shore, with its feed tube thrown into the water. After thirty minutes, the unit filled a plastic drinking cup with fresh water. Their research has been published online in Environmental Science and Technology.
In order to work effectively, the device uses ion concentration polarization, a technique developed by the research group ten years ago. This method applies an electrical field to membranes placed above and below a channel of water, which pushes away positively or negatively charged particles. Bacteria, viruses, dirt, and salt molecules are repelled as the water flows. These charged particles are led to a secondary water stream that’s flushed away.
Using the ion concentration polarization, suspended solids are removed, and clean water is allowed to pass through the channel. This technique is unlike other portable desalination units, which tend to employ high-pressure pumps to purify water using filters.
To ensure that all the salts float in the channel, the researchers also employ electrodialysis to remove possibly missing salt ions. The team developed the portable desalination unit to be both self-cleaning and require minimal energy usage. The team also created a smartphone app that can control the portable unit wirelessly and generate real-time data on water salinity to add a cherry on top.
This breakthrough is excellent news for the future of water conservation and efficiency, possibly providing communities with scarce freshwater with a way to generate drinkable water.