Both researchers say that the technology could have other applications beyond wastewater treatment. For example, they also want to explore ways to recover energy from nitrate-contaminated groundwater beneath fertilized agricultural fields. "We're thinking very broadly about all the ways nitrogen gets into the environment, and how we can exploit it," Cantwell said.
"If successful, this technology could be a game changer, with the potential for worldwide impact on several fronts," Criddle said.
Restoring the Earth's nitrogen cycle
The world's supply of nitrogen exists in a never-ending loop, moving from the atmosphere to nitrogen-fixing bacteria to plants and animals, then back to bacteria and, eventually, to the air.
But humans have broken this natural cycle, according to Criddle. "We now take more nitrogen from the air, mostly through the manufacture of agricultural fertilizers, than we give back," he said.
Tons of excess nitrogen fertilizer also flow into groundwater, rivers and eventually out to sea, where it feeds massive algal blooms that can damage marine ecosystems. Nitrogen also impacts human health. Too much nitrate in drinking water can be harmful to infants and pregnant women, according to the Centers for Disease Control.
"Slowly but surely the world is being contaminated with waste nitrogen," Cantwell added. "Restoring the balance is a critical thing to do for the future of the planet."
Farmers lose money when nitrogen is wasted, Criddle added. "But with the right technology, the balance of the nitrogen cycle can be restored and value recovered from waste nitrogen," he said.
|Contact: Mark Shwartz|