On-Farm Co-Digestion of Dairy Manure with High-Energy Organics (Anaerobic Digestion Systems Series)

The Anaerobic Digestion Systems Series provides research-based information to improve decision-making for incorporating, augmenting, and maintaining anaerobic digestion systems for manure and food by-products. Anaerobic digestion is a waste treatment process that occurs in an oxygen-free environment. In this process, microorganisms convert organic materials to biogas, a source of renewable energy. Besides producing energy, anaerobic digestion helps solve many environmental concerns associated with wastes, including odors, pathogens, greenhouse gas emissions (GHG), and air and water quality issues. At dairies and other livestock operations, the manure can be purposely mixed with other organic material such as pre-consumer food wastes to improve biogas yield, economics, and the AD process. This publication defines the co-digestion process and discusses major advantages and disadvantages.