Humic Manure Additive Reduces Odor from Pennsylvania Swine Finishing Operation

Abstract. A demonstration project was performed to document the efficacy of a proprietary humic-material for reduction of liquid swine manure odors at a full-scale commercial finishing operation. Two 2,250-pig, tunnel-ventilated, deep pit finishing barns located ~0.55 km (1800 ft) apart, operated in substantially identical manner by the same grower, were enlisted for the demonstration. One barn was treated with the amendment and the other was maintained as control (untreated). After a 20-week grow-out cycle, underfloor storage pits were emptied and manure surface applied on nearby fields. The process was then repeated with amendment treatment and control barns switched. Barn exhaust evaluations found that average barn odor emission rates were reduced by 21% (odor units/minute), with a statistical confidence >99% for both field and lab assessment methods. Additionally, land application odor concentration levels were reduced by 21% to 60%, with a statistical confidence of 85% and >99.9% for field and lab olfactometer assessment methods, respectively. Manure storage treatments with the humic amendment involved less than eight hours of labor over a hog finishing cycle, with an estimated cost of $0.70/hog (product + labor). This on-farm demonstration, together with laboratory and pilot scale studies that preceded it using the same product, indicate that humic amendment of swine manure can significantly reduce odor emissions. It is reasonable to expect odor mitigation effectiveness would be site specific; dependent on physical, chemical, biological, and metrological conditions.