Digester turns food waste into energy

SALEM, Ohio – Converting waste from dairy cows into renewable energy has been big news in recent years. Converting waste from dairy products into renewable energy hasn’t received as much attention, but a cheese plant in Fredonia, Pa., is looking to lead the way with this emerging technology.
Fairview Swiss Cheese Plant will break ground Oct. 11 on a $2.2 million anaerobic digester that will convert cheese whey and ice cream cone batter waste into renewable energy.
The ice cream cone batter will come from Joy Cone in Hermitage, Pa., which produces 1,500 gallons of waste batter each day. The cheese plant turns out about 20,000 gallons of whey every day that will be used in the digester.
How it started. The idea for the anaerobic digester took root in 2005. Tom Wilson, an agricultural engineer with Crawford County Cooperative Extension, said the original idea was to convert manure from area farms into renewable energy, but a local study showed that converting food waste would be a better fit.
“It turned out it was more economical to deal with the food waste,” Wilson said.
The project is being funded through a $375,000 grant from the Pennsylvania Department of Environmental Protection, a grant from USDA and a loan from the state’s First Industries Fund.
Using anaerobic digesters such as this one helps reduce the amount of food waste that ends up in landfills, Wilson said.
Unique. One of the most unique elements of this system is its short holding time. Within eight hours, 90 percent of the carbon in the food waste will be converted into biogas. In digesters that use manure, that process takes 21-27 days and biogas yields are not as high.
Food waste breaks down faster than manure, which speeds up the conversion time. Also, the digester at Fairview will allow more anaerobes (the organisms responsible for creating biogas) to live within the system, which will make the conversion faster, as well.
“It’s a simpler way to convert it into gas,” Wilson said.
Where it goes. The energy created by the digester will be used by the Mercer County cheese plant. Fairview Swiss Cheese Plant processes more than 30,000 gallons of milk into cheese every day.
It is owned by John Koller and Son Inc. with Rick Koller as president and managing partner.
(Reporter Janelle Skrinjar welcomes feedback by phone at 800-837-3419, ext. 22, or by e-mail at jskrinjar@farmanddairy.com.)