MIT engineers have created a portable device that zaps seawater to produce drinking water
A team of MIT scientists has created a device that turns brackish seawater into drinking water with the push of a button – and may be especially useful for people living in seaside regions like California who face droughts fueled by climate change.
The new desalination device (a term used to describe a machine capable of removing salt from seawater) is about the size of a suitcase, weighs less than 10 kilograms and consumes less energy than a cell phone charger, according to an article published in April. 14 in the log Environmental science and technology. With the push of a button, can automatically create drinking water that exceeds World Health Organization water quality standards.
“Even a kindergarten student can carry and use the desalination unit,” Junghyo Yoon, a researcher at MIT’s Electronics Research Laboratory and co-author of the paper, told The Daily Beast. “[Ease of use] was one of the main motivations for creating the device.
The device does not rely on any filters like traditional desalination machines. Instead, it zaps water with electric currents to remove minerals such as salt particles from the water. Due to its portability and the lack of filters to replace, it has a wide range of applications, including sending to seaside communities, climate disaster refugees or even doomsday preppers, according to Yoon.
“My team and I have been working on desalination technology for more than a decade now,” Jongyoon Han, professor of electrical engineering and computer science and biological engineering at MIT and lead author of the paper, told The Daily Beast. “This particular technology has gone through many different iterations and finally we have reached a milestone of a system that can be demonstrated.”
Yoon and Han’s new device solves a few problems that plague most commercially available desalination machines. For one thing, pushing water via pumps through filters is quite energy-intensive, so it’s hard to make a smaller, portable version of it. Instead, the MIT team’s device relies on a process called ion concentration polarization (ICP), which uses an electric field sent through membranes above and below a water channel. The field pushes charged particles and contaminants into a separate water channel which is discharged. This makes it possible to produce clean and drinkable water. “We apply an electric field in the water flow and the electricity helps remove particles like salt in the water,” Yoon explained. “This is the basic principle of the device’s desalination process.”
The researchers now want to build on their device to improve its production rate and ease of use. After all, the more water the device can produce at a time, the more people will be able to access safe drinking water. To that end, Yoon plans to launch a startup in the coming years to create a viable commercial desalination device using ICP technology with support from MIT.
However, Han said he has broader, longer-term goals for his desalination efforts. Specifically, he wants to take a more critical look at reverse osmosis (RO), a desalination process in which salty water is pushed through a membrane or filter, resulting in clean water. “It achieves quite good energy efficiency, but it has high maintenance needs and it only operates on a large scale, like a large factory,” Han said, adding that it is an inefficient process for places around the world like California where “the demand for water is always fluctuating” and currently urgently needs clean, potable water.
“This flow does not work well with a rigid desalination model used by a reverse osmosis plant,” he said. “So I’m thinking about how we can apply more flexible desalination processes, like ICP. It’s a very long-term direction that interests me.
He also explained that he wants to address challenges beyond desalination, including detecting and removing contaminants in water such as heavy metals and disease-causing pathogens such as viruses and bacteria.
“Most of these contaminants are open charge, so technically speaking we have the ability to remove a wide range of contaminants such as lead and bacteria,” Han said. “Going forward, we want to design our system to remove industrial contaminants. These prospects are very exciting.
#MIT #engineers #created #portable #device #zaps #seawater #produce #drinking #water