Submitted to: Proceedings of the Workshop on Agricultural Air Quality: State of the Science
Publication Type: Proceedings
Publication Acceptance Date: February 1, 2006
Publication Date: June 1, 2006
Citation: Moore Jr, P.A., Miles, D.M., Burns, R., Pote, D.H., Berg, K. 2006. Evaluation and management of ammonia emissions from poultry litter. In: Proceedings of the Workshop on Agricultural Air Quality: State of the Science, June 5-8, 2006, Potomac, Maryland. p. 304-310. Interpretive Summary: Ammonia evaporation from animal manure, such as poultry manure, results in high levels of ammonia in animal rearing facilities, which negatively impacts animal performance and worker health. Ammonia losses from these facilities also cause atmospheric ammonia pollution. Knowledge on the magnitude of ammonia emissions and methods to control ammonia losses are needed. The objectives of this study were to: (1) measure ammonia evaporation from poultry manure in chicken houses and from fields fertilized with manure, (2) evaluate the factors that affect ammonia losses from chicken manure, and (3) determine the impact of best management practices on ammonia loss. Four chicken houses with tunnel ventilation were equipped with a system to monitor ammonia concentrations and emissions from the house. In addition, the amount of ammonia, nitrous oxide and methane gases escaping from the manure surface were measured using flux chambers. Ammonia evaporation losses following land-application of manure were measured using wind tunnels. Results of the study showed one broiler chicken house containing 34,000 birds lost an average of 31 lbs of ammonia each day. An ammonia scrubber (a big box that purifies the air) that attaches onto the exhaust fans of animal rearing facilities was developed and tested. This scrubber was shown to significantly reduce ammonia concentrations in exhaust air from broiler houses. Ammonia loss from fields fertilized with chicken litter which was surface applied equaled 15% of the total nitrogen applied. However, when the poultry litter was incorporated, ammonia losses were virtually zero. These research indicates that there are several best management practices that can be utilized to reduce ammonia loss from poultry litter.
Technical Abstract: Ammonia volatilization from poultry litter results in high levels of ammonia in poultry facilities, which negatively impacts bird performance and worker health. Ammonia emissions from the houses also cause atmospheric ammonia contamination. Although there is a tremendous concern about these emissions currently, little quantitative data exists on the magnitude of ammonia fluxes from poultry litter. Hence, knowledge on the magnitude of these emissions, factors affecting emissions, and methods to control ammonia losses are needed. The objectives of this study were to: (1) measure ammonia volatilization from poultry litter in broiler houses and following land application, (2) evaluate the factors that affect ammonia losses from poultry litter, and (3) determine the impact of best management practices on ammonia volatilization. Four tunnel ventilated houses were equipped with ammonia sensors, anemometers, and data-loggers which continuously recorded the ammonia concentrations and ventilation (wind speed) at each of the windows in each house. In addition, ammonia, nitrous oxide and methane fluxes from the litter were measured using flux chambers. Nitrogen losses following land-application were evaluated using ammonia wind tunnels. Results of the study indicate that although ammonia emissions from one broiler house containing 34,000 birds can exceed the CERCLA reporting threshold of 100 lbs/day, losses are typically much lower than this value (average 31 lbs/day). An ammonia scrubber that attaches onto the exhaust fans of animal rearing facilities was developed and tested. The scrubber, which utilizes a dilute aluminum chloride solution to capture ammonia and dust, was shown to significantly reduce ammonia concentrations in exhaust air from broiler houses. The aluminum in the solution, which is converted to aluminum hydroxide prior to land application as the pH of the solution is increased by ammonia, immobilizes soluble phosphorus (P), which reduces the risk of non-point source P runoff. Ammonia emissions from land applied poultry litter totaled 34 kg N/ha (15% of the total N applied). When the poultry litter was incorporated, ammonia losses were virtually zero (N loss was not different from unfertilized control plots). These studies indicate that there are several best management practices that can be utilized to reduce ammonia loss from poultry litter.