ARS | Publication request: Odor control in swine buildings: recycle flush vs. automated scraper

Submitted to: ASABE Annual International Meeting
Publication Type: Proceedings
Publication Acceptance Date: June 16, 2011
Publication Date: August 7, 2011
Citation: Parker, D.B., Lim, T.T. 2011. Odor control in swine buildings: recycle flush vs. automated scraper. In: Proceedings of the American Society of Agricultural and Biological Engineers (ASABE) Annual International Meeting, August 7-10, 2011, Louisville, Kentucky. Paper No. 1111106.

Interpretive Summary: A research project was conducted to compare odor emissions from traditional flush barns to those with automated scrapers. The study was conducted at commercial tunnel-ventilated swine barns in northwest Missouri. Odor samples were collected from the barn exhaust in plastic bags and analyzed by trained human panelists. In addition, the individual compounds responsible for odor were analyzed and reported. Average odor concentrations in the barn exhaust were 75.6 percent lower in scraper barns than flush barns. Total reduced sulfur concentrations were 89.9 percent lower in scraper barns than flush barns. Odor was 1.65 times higher during the flushing period, an indication that the recycled flush water contributes considerably to the overall odor emissions. Cost to install a scraper system in a 1000-head finishing barn was $7,200. These results show that converting from a flush system to a scraper system is a practical alternative for odor control in tunnel-ventilated swine barns.

Technical Abstract: A research project was conducted to compare odor concentrations in exhaust of traditional flush barns and barns equipped with automated scrapers. The study was conducted at commercial tunnel-ventilated swine barns in northwest Missouri. Odor samples were collected from the barn exhaust in polyvinyl fluoride film bags (PVF) and analyzed by trained human panelists using triangular forced-choice olfactometry. Total reduced sulfur (TRS) concentrations were measured with a portable Jerome meter. Mean odor concentrations (dilutions to threshold, DT) were 75.6% lower in exhaust from scraper barns (DT = 941) than flush barns (DT = 3860) (p < 0.001). Mean recognition thresholds (RT) were 76.4% lower in exhaust from scraper barns (RT = 494) than flush barns (RT = 2095) (p < 0.001). TRS concentrations averaged 1.59 and 0.16 ppm in flush and scraper barns, respectively, for an 89.9% difference (p = 0.029). Cost to install a scraper system in a 1000-head finishing barn was $7,200. These results show that scraper barns are a practical alternative for the control of odor emitted from tunnel-ventilated swine barns.