Using Plasma Discharge to Make Water Safe to Drink
“We’re using water to clean water.”
This is how Selma Thagard describes her current work on purifying drinking water. The chemical engineering professor at Clarkson secured funding from the Environmental Protection Agency to conduct this first-of-its-kind research project.
“We’re taking a new purification process — pioneered here at Clarkson — and putting it to work in a pilot program. If we’re successful, people will be able to use this process to purify water for drinking and cooking. No one’s done this before with water treatment on this scale.”
The method begins by changing water from liquid to vapor.
“Then, we go beyond that,” she says, “heating the vapor until it becomes plasma. In this state, the molecules become highly reactive. I tell my students that we create lightning in liquids.”
This conversion happens in a plasma reactor that generates an electrical field so powerful that — within minutes — it can purify several gallons of drinking water.
“We’re not heating the water that’s being purified,” Thagard says, “so the plasma reactor requires much less energy than some traditional purification methods. People all over the world — especially in places with few resources — could use this process to remove toxins and water-borne parasites from their drinking supply.”
She praises Clarkson’s academic and research environment for creating the conditions that made this project possible.
“The availability of resources and facilities at Clarkson is huge,” she says, “without these things, it would be much harder to do this work. I also found a lot of helpful expertise among my peers, the faculty here. They helped me identify the scientific funding channels necessary to make this work possible. This is an excellent example of the potential of the Clarkson community.”
Selma Mededovic Thagard