Estimated read time: 3-4 minutes
This archived news story is available only for your personal, non-commercial use. Information in the story may be outdated or superseded by additional information. Reading or replaying the story in its archived form does not constitute a republication of the story.
PROVO — Two BYU professors are using a special bacteria to pretreat manure before it is converted into natural gas, maximizing the amount of energy made and reducing waste at the same time.
Chemistry professor Jaron Hansen and microbial ecology professor Zach Aanderud have been working on this project of "dirty business" for 10 years, devising a way to better transform waste into energy.
Machines called anaerobic digesters have been used for years to create energy from animal, food and human waste and plant matter, but Hansen found the digester is only 30-40% efficient at breaking down the matter and converting it to natural gas. He sought a solution to make the process more efficient and experimented with chemical, mechanical and radiational methods but none of them garnered the results wanted.
With the help of Aanderud, the two turned to a biological solution and discovered a special bacteria could do the job.
Hansen and Aanderud discovered if you pretreat the waste with a hyperthermophilic anaerobic bacterium, it breaks up the waste on a molecular level. After the waste has been pretreated, it is put into an anaerobic digester where it is converted into natural gas.
Through research, tests and laboratory trials, the professors found pre-treated waste doubled the efficiency to sometimes more than 80% and also was completed in half the time.
"The big breakthrough here is that before, we were limited in the efficiency of these digesters and of how much energy we could get out of this waste. We've now been able to almost double that efficiency," Hansen said.
The professors patented the process and their research made the cover of the Biofuel Research Journal, demonstrating how to inoculate waste with the bacteria and then use an anaerobic digester to convert the waste to methane gas.
In the last two weeks, the patent has been implemented commercially at large farms in Indiana and Wisconsin, with more on the way in Colorado. Hansen is hoping dairy farms in Utah will start using the process so they can reduce waste and create sustainable energy by reusing the multiple tons of manure they acquire every day.
"What are we going to do with all that waste? Now we can anaerobically digest it which reduces the mass of this waste that we have to dispose of and in the process of doing that we generate energy from it," Hansen said.
The natural gas can then be burned to generate electricity, compressed to power a car, or cleaned and put in a pipeline to heat homes or cook with.
"So it's a renewable energy source. We are taking waste and converting it into energy and we've doubled that efficiency," Hansen said.
Capturing waste and reusing it to become energy makes the professors' research a sustainable, resourceful practice. Hansen's team is working with some big engineering firms to transform municipal waste into natural gas.
Hansen said he has always been fascinated with the way the world works and through his work he hopes to "see if we can engineer it and understand it to better humanity."
The professors' work is far from over, and the two are already working on improving the process, but Hansen said he is grateful for the progress they've made. They have a team of undergraduate students, graduate students and professionals to help them continue their work.
"I couldn't have done this myself, but it's because of this team effort and the ability of so many people to work so well together. I'm really indebted to a bunch of talented, motivated great people to work with," he said.
