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Meet the USU professor who actually wants to grow more algae

USU researcher sees solutions in wastewater-grown algae, including algae-based plastics, fuels and fertilizer

(Utah State University) A Utah State University researcher scrapes algae grown as a test for cleaning wastewater of excess nutrients.

This story is part of The Salt Lake Tribune’s ongoing commitment to identify solutions to Utah’s biggest challenges through the work of the Innovation Lab.

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When you think of algae, you’re probably thinking about the goopy green slime that closes popular recreation areas like Utah lake. When one professor at Utah State University thinks about algae, he sees a myriad of opportunities.

Ron Sims leads a program at USU dedicated to growing algae in contained environments -- particularly wastewater treatment facilities -- that can clean water and be harvested to create products including fertilizer, fuels and even plastics.

“There was an old argument that if you’re going to have a good environment we can’t have industry, and if we have industry we’re not going to have an environment,” Sims said. “The new way to go is you build both. You protect the environment, and you build industry. We’re out to demonstrate that.”

Algae naturally grows in Utah’s wastewater treatment plants, and Sims actually wants to encourage that. Algae there can only grow a couple inches thick before blocking out sunlight for more plant growth., so Sims developed a barrel-shaped mechanism that slowly rotates to let more algae get sunlight.

“Instead of the algae growing in Utah Lake,” Sims said, “we grow it in an engineered environment where we can control and stimulate the growth and then get the algae out of there.”

Growing algae like this cleans the wastewater of nutrients that are hard to filter out, Sims said. The algae consumes nitrogen and phosphorus in the wastewater facility before being harvested. The process removes those nutrients that would otherwise flow downstream and fertilize the toxic algae in Utah’s waterways.

Grant funding for algae research

It’s not a crackpot idea either. At least the U.S. Department of Energy doesn’t think so. USU and Sims received a $1.9 million grant from the department to continue this research.

The machine that grows the algae -- called the Rotating Algal Biofilm Reactor, or RABR -- will be installed in the Central Valley Water Reclamation Facility in South Salt Lake next month with funding from the grant. Sixty million gallons of water -- enough to fill about 9 Olympic-sized swimming pools -- flows into the facility each day, giving Sims and USU the opportunity to study how well the system works at a commercial scale.

USU researchers are developing ways to turn the algae into vehicle fuel or farm fertilizer. Some is also sent off to Algix, a Mississippi-based biotechnology company that is developing ways to make plastics out of algae.

USU is readying a 3,000-square-foot facility called the Algae Processing and Products facility, or APP, for Sims and other researchers to study sustainable engineering with algae. With the large footprint, Sims and students will be able to test whether practices developed on a small scale in a lab can work effectively for larger, real-world applications.

“When you scale up [from a quart of water] to 500 gallons, you have a lot more challenges with regard to engineering and sustainability,” Sims said. “You can’t just put a little stirrer in there and mix things. You’ve got to figure out how you’re going to mix 500 gallons.”

Making bio-products

The students will also be developing ways to make diesel and other fuel out of algae. Regular vehicles would be able to use these fuels made from algae just as they would other fuels, Sims said.

That algae-based diesel will still emit air-polluting carbon, Sims said, but deriving diesel from algae that has captured CO2 in the process of growing would at least approach carbon neutrality.

“With petroleum, where you’re pulling it out of the ground and it hasn’t been around before and then you’re burning it -- that of course is adding to our greenhouse gasses,” Sims said. “But with this algae, it removes CO2 already in the atmosphere.”

Algae will also be developed at USU to create fertilizer for agriculture, Sims said. Farmers use nitrogen and phosphorus to produce better crop yields, but creating that fertilizer is expensive and energy-intensive.

The fertilizer made from algae, Sims said, could be less expensive and could release the nutrients to the crops more slowly which would also reduce the amount of excess nutrients that run off into waterways, preventing toxic algal blooms.

One of the goals of the project is to change the thinking of wastewater treatment, Sims said. For he and his students, the nutrient-laden water that flows through wastewater facilities is an opportunity, not a problem.

“Wastewater, to us, is a resource. It contains valuable nutrients,” Sims said. “We get the fertilizer for free, which is wastewater, and our crop becomes algae.”

With this new algal crop, Sims says he and his students can help the environment and public health by reducing nutrients that feed toxic blue-green algal blooms while also promoting sustainable jobs.

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Solutions in practice

Want to do your part in preventing toxic algal blooms? Utah State University recommends the following:

• Trim your lawn to 3 to 4 inches in length.

• Mulch your lawn clippings. Returning your grass to the lawn can reduce nitrogen fertilization needs by 50%.

• Use an inexpensive soil test to determine your actual fertilizer needs.

• Avoid midsummer fertilizing and practice proper irrigation techniques that avoid runoff.

USU lawn care guide: https://tinyurl.com/USUext.

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