Researchers Develop Process to Convert Poultry Litter into Bio-Oil

The research is funded by a $1 million grant from the National Fish and Wildlife Foundation's Chesapeake Bay Targeted Watershed Program.

Each year the poultry industry in the United States produces more than 5.6 million tons of litter – a mixture of bedding, manure, feathers and spilled feed. Team leader Foster Agblevor, associate professor of biological systems engineering at Virginia Tech, says current disposal methods such as land application and feeding to cattle are under pressure because of concerns related to pollution of water resources due to leaching and runoff and mad cow disease contamination in the food chain.

There also are concerns that poultry litter can harbor diseases such as avian influenza. Bird flu virus spreads on people's shoes, vehicles and through movement of litter.

The new pyrolysis unit heats the poultry litter until it vaporizes. Then the vapor is condensed to produce the bio-oil, and a slow release fertilizer is recovered from the reactor. The gas can then be used to operate the pyrolysis unit, making it a self-sufficient system.

“The self-contained transportable pyrolysis unit will allow poultry producers to process the litter on site rather than having to haul the litter to a separate location,” Agblevor says. “In addition, the thermochemical process destroys the microorganisms reducing the likelihood of the transmission of disease to other locations.”

Agblevor is working with poultry growers to test technology that would convert poultry litter to three products – bio-oil, producer gas and fertilizer.

The research is a cooperative effort by Virginia Tech researchers, Virginia Cooperative Extension specialists and agents, conservation organizations, state agencies and private industry to determine the most effective means to support the agricultural community and manage the excess nutrients in the Shenandoah Valley.