The odor-reduction capability of livestock wastewater treatment wetlands has been primarily anecdotal and presented as a benefit beyond the already widely recognized attributes. The objective of this study was to determine the long-term, odor-reduction performance of a vegetated, sub-surface flow wetland system on a swine farm. Reduced-solids swine manure from a scraped grow-finish facility was diluted with tap water and then delivered to constructed wetlands at a rate that provided a 4-d hydraulic retention time (HRT). Dilution produced a wastewater influent to the wetlands with total solids content that rangedfrom 0.21% (1:4 manure:water) to 0.53% (1:1 manure:water). During preliminary trials, wetland plants appeared to be a key component for successful year-round odor reduction. A trained human odor assessment panel determined that a significant reduction in odor intensity and increase in odor pleasantness (hedonic tone) occurred during wetland treatment from supply tank to effluent. Odor reduction was achieved for all trial dilution levels. The 1:2 manure:water dilution (0.31 % total solids) had the greatest odor reduction with a 64% improvement in odor pleasantness scores (near "neutral") and 49% improvement in odor intensity (qualitative evaluations dropping fiom "moderate" wetland influent odor to "weak" wetland effluent odor). The wetlands were found to treat a wide range of dilute manure ammonium and solids levels while providing significant odor reduction.
|Original language||English (US)|
|Number of pages||10|
|Journal||Applied Engineering in Agriculture|
|State||Published - Sep 1 2007|
All Science Journal Classification (ASJC) codes