UT researchers simplify water purification

A team of University of Texas researchers has created a 3D-printed device that could help increase access to clean water during extreme weather events.

Why it matters: Texas has faced a number of extreme weather events that have left communities without electricity or water, including the 2021 freeze and Hurricane Harvey. A device that would make drinkable water from creeks and streams could be essential in future emergencies.

What's happening: A research team led by D. Emma Fan, an associate professor in UT's Cockrell School of Engineering, created a 3D-printed, portable water-purification prototype that removed 99.997% of E. coli bacteria from samples of natural creek water, bringing it to a safe drinking level.

What they're saying: "When our water infrastructure is down — no water, no gas and no electricity — we need point-of-use devices for cleaning water we can get out of ponds, streams or rivers," Fan said. "We believe our device can someday fill that need."

Details: The device has a "branched," foam-encased electrode — similar to a tree's root system — that creates a field that E. coli cells are attracted to when electrified.

• The cells "swim" out of the water and into the electrode branches.
• The materials for the foam-encased electrode cost less than $2, which could be key in making the device widely available.

State of play: There are portable filter systems available, but researchers say the current devices have significant flaws.

• Disinfecting pills can release oxidants that can be harmful if ingested.
• Reverse osmosis systems that require high water pressure or solar steaming, which requires consistent sunlight, are not reliable in a natural disaster.
• With the electrode cup, researchers say a person under a boil-water notice could power the device with their car and a DC-AC converter or solar panels.

What's next: The researchers are now looking into ways to commercialize the device and streamline the design of the cup, including simplifying the process of inserting and removing the electrodes.