In the heart of Wisconsin, a project is underway to produce energy from a resource that is in little danger of running low: cow manure, or “brown gold.” Thanks to a $7 million grant from the United States Department of Agriculture (USDA) Biomass Research and Development Initiative (BRDI), the University of Wisconsin-Madison and several state companies have formed a consortium to pilot the conversion of dairy farm manure into useful product streams—a project that is expected to have significant environmental and economic benefits.
The Accelerated Renewable Energy (ARE) project is already in progress at the 5,000-cow Maple Leaf Dairy in Manitowoc County, where animal waste is separated into different streams, or fractions, of processed manure. After small plant fibers in the manure are separated out and anaerobically digested to create biogas, liquids from the digestion process are used to fertilize crops, while leftover solids can be converted into useful chemicals and bio-plastics. Larger plant fibers, on the other hand, make great animal bedding and mulch, as well as a starting material for ethanol fermentation.
WBI director and Biological Systems Engineering (BSE) faculty member Troy Runge, who is a co-investigator of the project, is interested in supporting a renewable energy economy through the development of value-added products from biomass. Runge’s lab is analyzing the ARE project’s separation techniques to improve their efficiency and economic performance.
“We are performing many of the same separations that occur on the farm, but in the controlled environment of the lab to both measure and optimize the system,” says Runge. Continue reading