A new digester facility in eastern Wisconsin is collecting 900,000 gallons of manure per day, and converting half of that as clean water and the other half as valuable fertilizer products and bedding. The gases from the manure are used as fuel for vehicles out West.
Bobby Levine is the CEO and founder of Digested Organics, which claims one of the largest manure digester facilities in the world in Greenleaf, Wisconsin. It’s a partnership with Dynamic Renewables. Levine tells Mid-West Farm Report that the facility is fostering better relationships between farmers and their community, as well as adding value to the 11 participating farms.
The two largest farms in the project are piping the manure to the digester, eliminating 24,000 trucks off the road each year, Levine explains. The concentrated nutrients and drinking-quality water can also go back to the farms via the pipeline. The project has a discharge permit to put that clean water back into rivers to help the environment.
The manure goes through several steps to create these end products:
- manure goes into digesters where biogas is collected, cleaned and injected into a pipeline to be used as transportation fuel in California
- the manure that comes out of the digester goes into a screw press, and solids are dried into fiber for bedding
- the liquid is further cleaned: ultrafiltration, super filtration, reverse osmosis, biofilter and ultraviolet disinfection before being released as drinkable water into the environment
- the nutrients taken out of that water are made into two concentrated products: a thick slurry of phosphorus and nitrogen, and a concentration of ammonia and potassium
The two fertilizer products are about three to four times more concentrated than raw manure, Levine says. Farmers can combine the two and treat it like manure, applying fewer gallons per acres. Or producers can keep them separate and make custom blends depending on the crop.
“Today, dairy farmers who do these digester products get value in lots of different models,” Levine says. Sometimes they get a check per cow or a percentage of biogas sales. In this project, they’re getting volume reduction.
“Again that’s lower trucking costs, better uptake of nutrients, having a lot more flexibility for storage, dealing with those tighter application windows that farmers have to deal with right now for manure,” Levine says. “That was more important to them than some fractional check of some gas sales. Keeping these farms healthy and sustainable in this community required that kind of volume reduction.”