Portable desalination device that converts seawater into drinking water, at the touch of a button, developed by MIT researchers. The device that looks like a suitcase, weighs about 10 kg and consumes less energy than a mobile phone charger.
The device uses electricity to remove particles from drinking water. The fact that the device does not require filters, significantly reduces the long-term maintenance requirements.
Portable desalination plants usually require high-pressure pumps to propel water through filters, which are very difficult to shrink without affecting the energy efficiency of the device, the scientists said in the press release.
device is based on a technique called ion concentration polarization (ICP), which the group developed more than 10 years ago. Instead of filtering water, the ICP process applies an electric field to membranes that are placed above and below a water channel.
Membranes repel positively or negatively charged particles – including salt molecules, bacteria and viruses. The charged particles are channeled into a second stream of water which is then thrown away.
The process removes both dissolved and suspended solids, allowing clean water to pass through the channel. Since it requires only a low-pressure pump, ICP uses less energy than other methods.
Also, because it does not always remove all the salts floating in the middle of the channel, the researchers incorporated a second procedure, known as electrodialysis, to remove the remaining salt ions.
The researchers also created a smartphone app that can control the device wirelessly and report real-time data on power consumption and salinity of water.
The resulting water exceeded the quality guidelines of the World Health Organization, and the unit reduced the amount of suspended solids by at least 10 times. The original device produces drinking water at the rate of 0.3 liters per hour and requires only 20 watts per liter.
Video from YouTube channel J-WAFS at MIT