Rebecca Larson, Assistant Professor
Department of Biological Systems Engineering
UW-Madison College of Agricultural and Life Sciences
Modern manure management
3:07 – Total Time
0:20 – How much manure there is
0:32 – Manure management techniques
0:51 – How an anaerobic digester works
1:31 – Adoption of digesters
2:02 – How manure separation works
2:26 – Manure research at UW
2:56 – Lead out
Manure management goes high tech. We’re visiting today with Becky Larson, Department of Biological Systems Engineering, University of Wisconsin, in the College of Agricultural and Life Sciences, Madison, Wisconsin…and I’m Sevie Kenyon.
Sevie Kenyon: Becky, welcome to our microphone. Becky, can you give us a sense of how much manure we have here in the State of Wisconsin?
Becky Larson: Here in Wisconsin, the dairy industry alone produces 400 swimming pools a day, just on the dairy manure here in Wisconsin.
Sevie Kenyon: What are some of the things producers are doing to manage manure?
Becky Larson: So we see producers now treating manure: anaerobic digestion, separation technologies, new storage and application methods. Particularly, one of the new things that we see have been a lot of anaerobic digestion systems.
Sevie Kenyon: Becky, can you describe for us how an anaerobic digester works?
Becky Larson: Yeah, anaerobic digestion… we call waste to energy technology. So, we take manure, put that in a large tank, and that can produce bio-gas. The main component of that is methane. We can take methane, put it in a generator, produce electricity…that’s the most commonly applied technology here in Wisconsin. We can also do new, advanced things we’re looking at using that methane to turn into vehicle fuel. We’re also coupling anaerobic digestion with other technologies, maybe such as a greenhouse, to utilize the nutrients in the waste after digestion.
Sevie Kenyon: Becky, can you give us an idea of how widely adopted some of these new technologies are in the state?
Becky Larson: Anaerobic digestion, we have more than thirty on-farm systems, I think we’re approaching about forty now. That’s the leading state within the United States, as compared to maybe Germany, which has seven thousand plus digesters. It’s a technology that right now is utilized only on large farms. We have seen a few small installations, but we’re hoping to really push that number up in the next few years.
Sevie Kenyon: Becky, can I get you to describe an example of one of these new technologies and how it works?
Becky Larson: With handling manure we see a lot of separation equipment. Manure has solids and a liquid component. So when we separate into a solid and maybe a liquid the liquid might be better used as a fertilizer, while the solid more easily shipped more cost effectively to different areas where nutrient loading isn’t quite so high.
Sevie Kenyon: And Becky, can you give us an idea of what kinds of things you’re researching here at the university?
Becky Larson: We have a farm-scale digester going in this spring up at the Marshfield Agricultural Research Station. We do quite a bit of work with manure storage liners now, so we’re trying to look at more effective ways to limit ground-water pollution and more effective ways to reduce green-house gas emissions, how you can handle manure. We have lots of separation technology research going on. Lots of new upcoming things related to manure.
Sevie Kenyon: We’ve been visiting today with Becky Larson, Department of Biological Systems Engineering, University of Wisconsin, in the College of Agricultural and Life Sciences, Madison, Wisconsin…and I’m Sevie Kenyon.