Comparison of Odor Dispersion at Swine Facilities and a Waste Processing Center Using a Eulerian-lagrangian Model

The purpose of this report is to compare odor dispersion at swine facilities that use alternative waste technologies (as well as a waste processing center) with odor dispersion at two control farms that use conventional lagoon technology. The goal was to determine if these alternative technologies reduce or substantially eliminate the emission of odor that is detectable beyond the boundaries of the parcel or tract of land on which the facility is located. Odor dispersion from these alternative technologies was compared to odor dispersion from two control farms using conventional lagoon technology in order to determine if the alternative technologies were superior to conventional procedures in reducing odors downwind. Twelve sites were evaluated: 1) Stokes farm (standard lagoon technology), 2) Moore farm (standard lagoon technology), along with ten alternative technologies including 3) Ambient Temperature Anaerobic Digester and Greenhouse for Swine Waste Treatment and Bioresource Recovery at Barham Farm, 4) “ReCip” Solids Separation – Reciprocating Wetland, 5) Constructed Wetlands at Howard Farm, 6)“Ekokan” Biofiltration Technology, 7) “BEST” (solids / liquids separation), Biomass Energy Sustainable Technology Site 1 (FAN + TFS), 8) “BEST” (solids / liquids separation) Biomass Energy Sustainable Technology Site 2 (Filtramat + TFS), 9) “ORBIT” High Solids Anaerobic Digester, 10) BELT (LWRFLsite), 11) “Super Soils” Solids Separation / Nitrification-Denitrification / Soluble Phosphorus Removal / Solids Processing System, and 12) BELT (Grinnells lab, NCSU campus). The trajectory and spatial distribution of odor and odorants downwind of each of the facilities (the alternative technologies and two controls) under two meteorological conditions (daytime and nighttime) were predicted using a Eulerian-Lagrangian model. The model was validated with experimental data. In general, the odor tended not to extend beyond the property boundaries of any of the farms during the daytime (when no spray irrigation of lagoon effluent was occurring ) when the layer of air above the earth’s surface is usually turbulent. However, odor can extend greater distances in the evenings when deep surface cooling through long-wave radiation to space recreates a stable