Now, sea water can be turned into drinking water without using filters
Seawater contains high amount of salt, which cannot be processed by the human body. That is why, it is not possible to drink sea water. However, the good news is that it can be easily converted into drinking water now, thanks to a new invention. Recently, an electricity-based, portable water desalination unit has been developed by Massachusetts Institute of Technology (MIT) scientists. The findings of this research have been published in the Environmental Science & Technology Journal in April 2022.
Using the ion concentration polarisation (ICP) and electrodialysis methods, the team of researchers led by Jongyoon Han, Professor, Electrical and Biological Engineering, MIT, has created a filter-less, suitcase-sized device. It can remove particles and salts to generate clean, drinking water.
How does the portable desalination device work?
The portable desalination device, which weighs less than 10 kilograms (22 pounds), uses ion concentration polarisation (ICP) technique to make sea water drinkable for human consumption. ICP involves pumping sea water through a tiny channel placed between two electrically charged membranes. One is positively while the other negatively charged.
Particles such as salt molecules, viruses, and bacteria are ejected into a channel of water that is discharged and not utilised as the water passes over the electrical field between the two membranes. Although the main water channel is cleansed and desalinated, it may still contain some salt ions. It then goes via an electrodialysis technique at this point. Electrodialysis is a water desalination process in which unwanted ions are removed from the salt solution by means of a direct current passing between two electrodes, one on each side of the membrane. Electrodes are substances that allow electricity to pass through them. Ion polarisation is a phenomenon that occurs when an ion (an electrically charged atom/ group of atoms) current is passed through ion-selective membranes.
What are the features of the portable desalination device?
This device is the size of a suitcase, and uses less energy than a cell phone charger. Yes, you heard us right. Moreover, this device can be activated by pressing a single button. Unlike earlier portable desalination devices that required water to pass through filters, this gadget removes particulates from drinking water using electricity.
Since it runs on electricity, the long-term maintenance requirements are going to be considerably reduced by eliminating the need for replacement filters in the device. Hence, this portable desalination unit could also be used in remote areas and places having limited water resources.
According to MIT researchers, it can also be powered by a small, portable solar panel that can be purchased online for around $50 (around Rs 3,800 at current currency rates). Moreover, according to a press release shared by MIT, the device produces drinking water that meets or surpasses World Health Organisation (WHO)’s quality criteria. The researchers also developed a smartphone app that can remotely manage the unit and provide real-time statistics on power consumption and water salinity.