Two researchers turned a great idea into innovative technology to clean chemicals and pharmaceutical residuals from the environment at a fraction of the cost of conventional remediation methods. Now they are commercializing their plasma discharge system with an eye toward revolutionizing the field.
Contaminated groundwater is a toxic legacy of inadequate storage and disposal of agricultural and industrial chemicals, like pesticides and petroleum products. Chemical treatment techniques have been largely successful in removing these contaminants from water and soil.
But newer classes of chemicals are proving harder to remove by conventional remediation systems.
Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals that have been used in industry and consumer products -- like water-repellant clothing, nonstick cookware, and stain-resistant carpets -- for decades. PFAS are of growing concern because of their persistence in the environment.
That’s where Selma Mededovic Thagard, associate professor of chemical and biomolecular engineering, and Thomas Holsen, the Jean S. Newell Distinguished Professor of Engineering, come in. Thagard’s expertise is in the design and construction of plasma chemical reactors for environmental applications. Holsen’s work centers around the transport, modification and fate of organic chemicals in natural environmental systems.
Together, the two researchers have developed an electrical plasma discharge system that effectively removes PFAS from contaminated groundwater and soil.
The system uses bubbles to move the PFAS in the groundwater to the water surface where they are treated with plasma. The conversion occurs in a plasma reactor where plasma is generated using a powerful electrical field that can purify gallons of water in minutes. The process breaks down PFAS into less toxic products that either remain in the water or are released into the atmosphere as harmless gases. It requires no chemical additives and produces little residual waste.
But there are other benefits to this innovative remediation system too.
“The process is faster, requires less energy and is far less expensive than traditional water purification methods,” says Thagard.
The researchers are commercializing this technology through their Potsdam-based company, DMAX Plasma. Launched in 2014 with outside investor funding and assistance from Clarkson’s Shipley Center for Innovation, the company is scaling up the technology for use in large-scale clean-up efforts.
“We are working to speed up the purification process to 50 gallons per minute,” says Holsen. “Ultimately, we hope to be at 100 gallons per minute.”
With more than $1 million in funding from the U.S. Air Force, Thagard and Holsen will test the system in the field this spring, at a military site contaminated with PFAS from foams used in fire-fighting training. They have also received funding from the Department of Defense and have two EPA grants pending.
They’re also getting a lot of attention in the field for this potentially game-changing technology.
Their success, they say, is the result of collaboration. “Selma understands the fundamentals of plasma and plasma reactors,” says Holsen. “My side is chemistry and application in the field.”
“We needed both points of views to make this happen.”