Project to Help Farmers Recycle Water, Recover Nutrients for Fertilizer

University of Arkansas chemical engineering faculty are leading efforts to develop systems to help farmers recycle water and recover nutrients that can be used as fertilizer. The research is being funded with a new $4.3 million grant from the U.S. Department of Agriculture’s National Institute of Food and Agriculture.

Agriculture accounts for more than three-fourths of all water consumption in the United States, according to the U.S. Department of Agriculture. In order to help farmers save water, Lauren Greenlee, assistant professor of chemical engineering, will work with other researchers and local farmers to design water recycling technology, as well as creating a decision-support tool farmers can use to choose the appropriate technology and system for their land.

“Important nutrients present in liquid manures, particularly nitrogen and phosphorous, are lost to the environment but could be recycled and re-used for food production,” Greenlee said. “Our goal is to build robust technology and  provide other tools to help farmers manage water resources and recover nutrients that could be applied to crops, as well as recover and recycle water.”

Lauren Greenlee and members of her research team in their lab at the Nanoscale Material Science & Engineering Building.

The grant provides support for Greenlee’s work on electrochemical processes for treating nutrients in wastewater. This process involves the use of electrodes applied to a fine membrane as a way to filter or separate nutrients from wastewater and convert them into fertilizer.

Greenlee’s team will work with regional farmers through organizations such as the Arkansas Farm Bureau in the development process. Greenlee is also collaborating with researchers at the University of Missouri, University of Nebraska-Lincoln, Colorado School of Mines and Case Western Reserve University. The researchers will compare their system to commercialized, “off-the-shelf” technologies used in industries outside agriculture.   

The project includes several additional U of A researchers as well:

• Greg Thoma, professor of chemical engineering, will provide life-cycle analyses to predict the environmental impact of implementing technologies to remove nutrients from liquid manure.
• Jennie Popp, professor of agricultural economics and agricultural business and associate dean of the Honors College, will examine the economic impact of adopting these tools.
• Kristofor Brye, professor of applied soil physics and pedology, will study the composition, chemistry and viability of the fertilizer and recycled waters, comparing it to commercial fertilizers.

The award is part of a $34 million USDA-sponsored initiative to address water scarcity. Six other research groups were chosen from 88 proposals.

Greenlee holds the Louis Owen Professorship in Chemical Engineering. Thoma holds the Bates Teaching Endowed Professorship in Chemical Engineering.