The Fibrominn LLC power plant in Benson, Minn., will produce 55 megawatts of electricity from turkey litter, a combination of droppings, wood chips, seed hulls, dropped feathers and spilled feed generated in huge quantities by Minnesota's turkey industry, the nation's largest.
The technology for actually burning the litter, producing power and controlling emissions isn't very different from the technology for burning coal in a power plant, plant manager Jack Jones said.
"This will be much cleaner than a coal plant," said Chuck Wagoner, the plant's construction manager.
The unique features are the procedures and technology for handling the litter and containing the odor and for managing the large volume of truck traffic, Wagoner said.
Fibrominn expects to get up to 100 truckloads of turkey litter a day, 5 1/2 days a week. The trucks are covered to control odor.
At the plant, trucks back into a large, closed fuel hall kept under a lower air pressure than the surrounding atmosphere, and dump their litter in a pit. The boiler draws its combustion air from a large duct leading from the fuel hall, so the odors are burned instead of escaping to the outside.
An automated crane system sorts the litter by moisture content and feeds it to an enclosed conveyor system that carries the litter to the boiler, where it's burned.
The empty trucks go to a separate building where they're washed and disinfected.
Around 20 percent to 25 percent of the plant's fuel mix will be other forms of biomass such as corn stalks, prairie grass and wood chips.