AMES, Iowa (AP) - Two Iowa State University scientists believe algae can help cut costs for hundreds of small Iowa towns that face up to $1 billion to upgrade their wastewater treatment to meet tougher clean water standards.
About 275 small communities face costly wastewater treatment upgrades to meet tighter permit requirements.
“We need a better way to have people flush their toilets and get that water treated. Otherwise, we’ll bankrupt rural Iowa,” said Craig Just, a University of Iowa assistant engineering professor. He’s part of a professional group hoping to help assess some of that new technology.
ISU’s Martin Gross and Zhiyou Wen could be part of the answer. They have developed a system that uses algae to remove phosphorus and nitrogen from wastewater, cleaning water before it’s released into the state’s rivers and streams.
The Des Moines Register (https://dmreg.co/2lETdvb ) reports that the men spun off their research into a startup: Gross-Wen Technologies, based in Ames.
The company’s system uses vertical conveyor belts, about 6 feet tall and 3 feet wide, that move in a continual loop, cycling through the wastewater and air as multiple layers of algae grow on them. The algae is then turned into fertilizer pellets.
“Algae needs sunlight, carbon dioxide and nutrients, such as nitrogen and phosphorus, to grow,” said Gross, a postdoctoral fellow at ISU’s Center for Crops Utilization Research. And “wastewater has nitrogen and phosphorus that needs to be removed.”
“We grow the algae while we’re treating the wastewater, then the algae gets harvested . and becomes a slow-release, pelletized fertilizer,” said Gross, the company’s CEO.
Wen, the company’s chief technology officer, is a professor in ISU’s food science and human nutrition department.
“We take nitrogen and phosphorus from an area where they’re not wanted,” Gross said, “and then put them . on crops where they’re wanted and needed.”
The technology is getting tested at big and small utilities - from the Metropolitan Water Reclamation District of Greater Chicago, the world’s largest wastewater treatment plant, to Dallas Center, a town of about 1,600 residents in central Iowa.
The Chicago operation has pumped about $410,000 and three years into testing the technology.
“We’ve explored three processes, and this technology shows the most promise,” said Dave St. Pierre, executive director of the Chicago reclamation operation. “It shrinks the footprint significantly and allows you to harvest algae” without the mess associated with other approaches.
St. Pierre said the technology helps cut the investment needed to reduce nutrients leaving the plant - and it generates money.
“We believe we can produce 64 tons of algae a day” when the technology is scaled up, he said. “We could produce a cash crop that would help us with our operating costs - to the order of $30 million a year.”
That kind of math makes the technology attractive, St. Pierre said.
“It would be something other wastewater plants wouldn’t have to think very hard about upgrading and investing in,” he said.
In addition to fertilizer, Gross said the algae biomass also could be used to produce bio-plastics or biofuels.
ISU tests show differences between algae and off-the-shelf fertilizers, Gross said.
It’s unlikely, though, that the algae fertilizer can replace the large amounts of fertilizer that Iowa growers need to raise crops such as corn, said Gross and Darren Jarboe, Gross-Wen’s vice president of business development.
Algae fertilizer is probably better suited for home gardeners and small fruit, vegetable and flower growers, they said.
“It could be good for organic growers, although we’re not sure it meets organic standards yet,” Jarboe said. “It would have to be certified.”
Gross believes the technology could help small communities cut the costs they face to upgrade their wastewater treatment systems.
Regulations that went into effect in 2006 mean hundreds of Iowa towns will face stricter permitting requirements to cut nitrogen ammonia and bacteria over several years. The state estimated that the costs would be close to $1 billion.
For example, Gross said, small rural communities that use a lagoon treatment to treat wastewater could face $2.5 million to $5.5 million in improvements.
“It’s a huge burden on a small tax base,” he said. “We think we can save communities a lot of money.”
Gross said the company hopes to site its first commercial system this year in a small town.
Larry Bryant, a senior environmental engineer at the Iowa Department of Natural Resources, said Gross-Wen Technologies has presented data about its process, but the agency hasn’t yet done a formal review. That would happen when a community seeks to use the technology to upgrade its plant.
Jarboe and Gross said the company has been working with some existing manufacturers to build the algae systems and the greenhouses that enclose them. If the technology takes off, the company’s manufacturing partners would add workers to build the equipment.
Gross said water quality is a significant state and national issue.
Iowa lawmakers are considering funding proposals this year that can help the state implement the Iowa Nutrient Reduction Strategy.
The plan is designed to reduce by 45 percent the nitrogen and phosphorus levels that leave rural and urban areas and contribute to the Gulf of Mexico dead zone, an area about the size of Connecticut that’s unable to support aquatic life because of nutrient pollution.
In 2015, Des Moines Water Works filed a lawsuit against drainage districts in three north Iowa counties, claiming underground drainage tiles funnel high levels of nitrogen from farm fields into the Raccoon River, a source of drinking water for 500,000 central Iowa residents.
That lawsuit is scheduled to be heard in June.
“Those nutrients end up in the waterways, causing problems like we see in Des Moines … or end up in the Gulf of Mexico and cause hypoxia,” Gross said. “There’s a new need for wastewater technologies.”
Just, the University of Iowa professor, has asked state leaders invest $2.75 million to test developing technologies at Iowa City’s wastewater treatment center. It could help save small communities millions of dollars and help scientists test good ideas.
“We’ve got some work to do in Iowa,” he said.
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Financial incentives
Gross-Wen Technologies received a competitive $100,000 federal grant, as well as a $25,000 Iowa Innovation Corp. grant, to develop algae fertilizer and test it.
The company also received a $25,000 Iowa Economic Development Authority loan for commercialization; a $25,000 investment from the Ag Startup Engine, a partnership between ISU and private ag investors; and $225,000 from angel investor Dave Furbush, founder of Midwest Project Partners.
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Information from: The Des Moines Register, https://www.desmoinesregister.com
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