New production facility delivers made-to-order algae

Posted on July 9, 2013

A new algae production facility at Iowa State University makes use of an innovative design that’s attracting interest from other universities and private industry.

The algal production facility, which was built inside a greenhouse on the BioCentury Research Farm in rural Boone, went online in January and has been filling orders for algae researchers ever since.

A greenhouse at the ISU BioCentury Research Farm houses new technology that simplifies the cultivation of algae. Photo courtesy of the Center for Crops Utilization Research.

A greenhouse at the ISU BioCentury Research Farm houses new technology that simplifies the cultivation of algae. Photo courtesy of the Center for Crops Utilization Research.

The facility contains a novel biofilm-based cultivation system designed by Martin Gross, a graduate assistant in agricultural and biosystems engineering, and Zhiyou Wen, an associate professor of food science and human nutrition.

The cultivation system allows for easy separation of algae from water, which is usually an expensive and often time-consuming process requiring the use of a centrifuge or other costly equipment. The new cultivation system at Iowa State sidesteps that process by passing through the nutrient-rich water a cotton-based biofilm, which collects the algae. After that, the algae are simply scraped off the cotton material. It’s a simpler, more efficient way to cultivate algae, Wen said.

He said there are similar competing technologies at other institutions, but there are differences that make the ISU technology unique. In fact, Wen and Gross are in the process of getting the technology patented.

“We knew that harvesting the algae is the most expensive and time-consuming part of the process, so we wanted to find a solution that was easier than traditional harvesting,” Wen said.

The ISU facility features a pair of raceway ponds, or small pools of water in which a weak current is constantly generated to keep the water moving. Gross described the system as similar to a lazy river – an attraction at public pools and water parks that features a shallow channel of water with a gentle current. One of the raceway ponds requires the use of a centrifuge, while the other employs the new system designed by Wen and Gross. The greenhouse also contains four, 200-liter flat panel bioreactors, another popular algae cultivation technology.

The reasons to study algae, a diverse group of chiefly aquatic and photosynthetic organisms, are nearly as varied as the organisms themselves. Scientists are exploring the potential for algae to be used as a fertilizer, a source of biofuel and as a feed supplement for production animals, just to name a few of the possibilities.

Such widespread application means there’s no shortage of interest in the new ISU production facility. Gross said faculty members from disciplines across campus are using algae produced in the greenhouse in their own research. Even private companies are using algae produced at Iowa State.

Gross said the new facility surpasses the capacity of any means of algae production seen on campus before. It’s capable of producing about 4.5 kilograms of algae per week, he said.

“I had been involved with algae research at Iowa State for three years, and we had to pass up several opportunities because we simply didn’t have a means of producing enough algae,” he said. “The new facility allows for us to pursue those kinds of opportunities on a larger scale.”

Source: Iowa State University