MANURE

With the objective to develop novel waste-to-resource technologies capable of converting organic wastes into value-added fuel and chemical products, Dana Kirk, Ph.D., P.E. in biosystems and agricultural engineering at Michigan State University, had his work cut out for him.

In partial response to the energy crisis in the early 1970s, anaerobic digesters were installed at nearly 200 dairy farms across the U.S., only for the vast majority of these systems to shut down or fail after just a few years of operation.

One of the greatest expenses associated with raw manure is transportation, due to the huge amount of manure (volume and weight) and distances between dairy sites and application lands.

The first consideration about manure is to change the mindset of manure being a waste product to being a resource. With that assumption, there are multiple variables that influence manure transportation and application considerations.

Management of manure is growing in importance for dairymen given a variety of issues that range from the inherent desire to protect the environment to the need to ensure profitability.

One option often considered for dairy farmers currently operating an anaerobic digestion system is the co-digestion of off-farm substrates.