The research objectives are:
- To measure air emissions from poultry housing units
- To measure air emissions from litter storage facilities
- To measure ammonia emissions from the land application of litter
- To assess nitrogen loss via ammonia emissions from deadstock composting
Air contaminants, such as gaseous ammonia (NH3) and particulate matter (PM), are an inevitable byproduct of poultry operations. While other research has focused on the concentration of specific pollutants and emissions, this study explores a complete suite of pollutants, and their interactions and implications to farm practices. The results will provide insight into new methods for controlling pollution – which could have significant economic impact for the industry, while demonstrating its commitment to minimizing environmental impact.
Air emissions from poultry housing units
The researchers measured emission of PM (categorized as up to 2.5 microns, PM2.5 and up to 10 microns, PM10), secondary inorganic aerosols (SIA), NH3, acid gas and methane (CH4) from a broiler facility. This is the first known study to attempt to quantify the contribution of SIA to the high levels of PM2.5 found in poultry houses. PM2.5 are formed by the reactions of specific gaseous pollutants that create airborne salts and liquid aerosols. Ammonia is involved in the formation of SIA, and with the high ammonia levels present in poultry barns, it is possible SIA particles may be contributing to the high PM2.5 levels observed. Using control methods that target NH3 would help to reduce exposure to human workers and the birds. The researchers correlated variables of the barn environment that were easy to measure (temperature, relative humidity, bird mass) with the actual measurements, making it possible for producers to estimate the emissions from their barns.
Air emissions from litter storage facilities
Methane and nitrous oxide (N2O) emissions from a concrete manure storage facility were measured over a three month period (Feb. to Apr.). Methane emissions were higher than observed from solid cattle manure and less than liquid swine manure. In contrast, N2O emissions from the broiler litter were slightly greater than emissions measured from cattle manure and much greater than liquid swine manure.
Ammonia emissions from the land application of litter
The volatilization of ammonia upon land application of litter/manure is a major source of nitrogen loss, presenting both environmental and economic concerns. The researchers developed a simple, economical method for measuring nitrogen loss that will be suitable for small plot studies or for farmers to use as a management tool. The simplified method, using a device known as a dositube, produced results similar to previous, more elaborate methods. Broiler manure spread at the equivalent of 200 kg N per hectare lost approximately 25% of its nitrogen in 3 to 5 days.
Nitrogen loss via ammonia emissions from deadstock composting
Composting poultry mortalities is a cost-effective, sustainable, environmentally-friendly approach to deadstock disposal, and it produces a valuable soil amendment in the form of nitrogen. The researchers looked at the effect of three different compost amendments on nitrogen loss, as well as carbon dioxide (CO2) and CH4 loss. Results of the study indicate that nitrogen loss was highest in the pile amended with poultry litter, as compared to that of the control (wood chips) or finished poultry compost. These findings indicate that, contrary to current recommendations in the agricultural literature, using poultry litter may not be the most effective amendment for composting deadstock. The resulting increase in ammonia emissions can result in odour problems and nutrient loss.
Future WorkAir emission measurements taken at the broiler facility will be repeated at a layer farm. Future work will concentrate on emissions from facilities, where the researchers claim the largest information gap exists.
Funding$245,563 (CPRC $106,063, NSERC-CRD $117,500, PIC $22,000)
PublicationsRoumeliotis, T.S., B.J. Dixon, B.J. Van Heyst, 2010a, “Evaluation of an Annular Denuder System for the Measurement of Elevated Concentrations of Gaseous Ammonia,” Biosystems Engineering,107: 178-185.
Roumeliotis, T.S., B.J. Dixon, B.J. Van Heyst, 2010b, “Characterization of Gaseous Pollutant and Particulate Matter Emission Rates from a Commercial Broiler Operation Part I: Observed Trends in Emissions,” Atmospheric Environment, 44: 3770- 3777.
Roumeliotis, T.S., B.J. Dixon, B.J. Van Heyst, 2010c, “Characterization of Gaseous Pollutant and Particulate Matter Emission Rates from a Commercial Broiler Operation Part II: Correlated Emission Rates,” Atmospheric Environment, 44: 3778-3786.
Roumeliotis, T.S., and B.J. Van Heyst, 2007, “Size fractionated particulate matter emissions from a broiler house in southern Ontario, Canada,” Sci. Total Environ.,383: 174-182.