USU biology students put bacteria to work

Natalie Larson

Students at Utah State University are working on a project through the Agricultural Systems Technology and Education (ASTE) department to help make large manure producers more environmentally friendly and profitable.

“There is potentially enough animal waste in Utah from pigs and cows to power 150 million homes,” said Todd Miller, a pre-med senior in nutrition and food sciences who is working on the project.

This project uses biological methods to naturally clean the waste, Miller said.

“I’d love to see all the big operations run on a system like this,” Miller said.

The project began about a year ago when Dr. John Harrison came up with the idea, and Miller and Ben Sessions, a chemistry senior, started working with it in April 2001, Miller said.

“Dr. Harrison has given us authority to do what we want with the project, so the fruits we reap are ours,” Sessions said.

They started by developing calculations to determine the necessary size of a facility based on the amount of waste an operation produces, Miller said.

They replaced the old anaerobic pit, which was too small, with a bigger one, and since than the project has been progressing, Miller said.

This project uses a two-cow scale model, and it is called an Integrated Facultative Pond system (IFP), Miller said. It can be scaled up for any size of operation.

The beneficial products produced through the cleaning process are duckweed and other types of plants that can be fed to animals and biogas, which can be used to produce electricity or heat water, Miller said.

One of the other types of plants is a type of algae called Spirulina, which is “the most nutrient dense plant on the planet,” Miller said. Spirulina is valuable as a nutricutical, or nutrition supplement.

Duckweed was chosen for this project because it is so high in protein and omega-3 fatty acids, Miller said. Dairy farmers typically have to give their animals protein supplements.

Duckweed could also be used to feed fish, Sessions said.

“They love it,” he said.

The waste water comes from the Caine Dairy, Miller said, and they pump it into an anaerobic pit. Bacteria in the pit break down the solids and produce the biogas, which is collected in a tank.

The biogas is burned to create electricity and is almost as clean a natural gas, Miller said.

Next, the waste water is moved to an aerobic pond where more bacteria break it down further, Miller said. Then it is biofiltered through a series of pools which each contain a different type of plant. These plants leach out the nutrients in the waste and leave the water clean enough to be put back into the environment without causing damage.

The aerobic pond is set directly above the anaerobic pit and stops the smell from the waste water, Sessions said.

Sessions, who grew up on a farm, said there are many problems farmers must face with urbanization, and implementing this will help reduce the pressure from neighbors to eliminate odor.

This type of system would cost a large producer about $10,000 to $50,000, Miller said.

“They wouldn’t have to pay an engineer to design it because we’ve already done that,” Miller said.

If everything continues to work has it has been, it will be about five years before they have enough data for people to completely accept it, Miller said.

“We’re not at 100 percent of our potential right now, but we’re studying all aspects to make it better and better,” Miller said.

This project is unique in the fact that undergraduates are doing the research, Miller said. It’s beneficial for undergraduates to be able to say they have worked on research projects.

Currently, there are seven undergraduate volunteers working with the project, Miller said. They all come from agricultural backgrounds and are able to work on their own spin-off projects relating to the main one, he said.

One volunteer is working on research environment conditions to optimize the growth the duckweed, Miller said.

The microbiology club is recommending volunteers to work with the project, and there are still openings for more volunteers, Miller said.

The volunteers are very helpful because they bring new perspectives to the project, Miller said.

Miller and Sessions are working on four journal articles to be finished in December and published within the year detailing some of their findings.

For questions about the project or to volunteer, contact Miller at tmiller@cc.usu.edu.