Effect of Nanobubbles on Dairy Manure Green House Gasses (GHGs)

Researcher: Dr. Frank Mitloehner, UC Davis Department of Animal Science
Timeline: January 2024 – December 2025

Background: Nanobubbles are spherical gas-filled nano-cavities with diameters of 10 – 200 nm. Nanobubbles have been safely applied to domestic and industrial wastewaters. The technology can generate free radicals that can oxidize organic matter in wastewaters. The application of nanobubbles to different dairy manure streams could potentially reduce the emissions of methane by at least 90% because the redox potential in manure will be at least +200 mv, which is not suitable for the growth of methanogens. It may increase the emissions of nitrous oxide but at lower rates compared with conventional aeration. It may also improve solid separation in the treated manure (e.g., in settling basins). This will lead to less accumulation of solids in lagoons that reduces the needs for the frequency of lagoon cleaning.

The technology could also improve irrigation efficiency, soil properties, water use, and crop yield.

Industry Benefit: The proposed work will guide the dairy industry to determine the effectiveness of nanobubbles as a novel technology for mitigating emissions and improving manure characteristics. Based on the data available on wastewater treatment with the nanobubbles, it is expected that the application of nanobubbles to dairy manure will save 40%-60% of the operation maintenance costs compared with conventional aeration. The proposed nanobubbles system is scalable and has a great chance for replicability on California dairies. The cost of applying this technology on dairies will be conducted in this project. The results will help to document the economics of implementing and operating the technology.