Effects of Treated Manure Conditions on Ammonia and Hydrogen Sulfide Emissions from a Swine Finishing Barn Equipped with Semicontinuous Pit Recharge System in Summer

Gaseous emissions from animal production systems affect the local and regional air quality. Proven farm-scale mitigation technologies are needed to lower these emissions and to provide management practices that are feasible and sustainable. In this research, we evaluate the performance of a unique approach that simultaneously mitigates emissions and improves air quality inside a barn equipped with a manure pit recharge system. Specifically, we tested the effects of summertime feeding rations (used by farmers to cope with animal heat stress) and manure management. To date, the pit recharge system has been proven to be effective in mitigating both ammonia (NH3; approximately 53%) and hydrogen sulfide (H2S; approximately 84%) emissions during mild climate conditions. However, its performance during the hot season with a high crude protein diet and high nitrogen loading into the pit manure recharge system is unknown. Therefore, we compared the emissions and indoor air quality of the rooms (240 pigs, ~80 kg each) equipped with a conventional slurry and pit recharge system. The main findings highlight the importance and impact of seasonal variation and diet and manure management practices. We observed 31% greater NH3 emissions from the pit recharge system (33.7 ± 1.4 g·head−1·day−1) compared with a conventional slurry system (25.9 ± 2.4 g·head−1·day−1). Additionally, the NH3 concentration inside the barn was higher (by 24%) in the pit recharge system compared with the control. On the other hand, H2S emissions were 55% lower in the pit recharge system (628 ± 47 mg·head−1·day−1) compared with a conventional slurry pit (1400 ± 132 mg·head−1·day−1). Additionally, the H2S concentration inside the barn was lower (by 54%) in the pit recharge system compared with the control. The characteristics of the pit recharge liquid (i.e., aerobically treated manure), such as the total nitrogen (TN) and ammonium N (NH4-N) contents, contributed to the higher NH3 emissions from the pit recharge system in summer. However, their influence on H2S emissions had a relatively low impact, i.e., emissions were still reduced, similarly as they were in mild climate conditions. Overall, it is necessary to consider a seasonal diet and manure management practices when evaluating emissions and indoor air quality. Further research on minimizing the seasonal nitrogen loading and optimizing pit recharge manure characteristics is warranted

Pilot-Scale Testing of UV-A Light Treatment for Mitigation of NH3, H2S, GHGs, VOCs, Odor, and O3 Inside the Poultry Barn

Poultry farmers are producing eggs, meat, and feathers with increased efficiency and lower carbon footprint. Technologies to address concerns about the indoor air quality inside barns and the gaseous emissions from farms to the atmosphere continue to be among industry priorities. We have been developing and scaling up a UV air treatment that has the potential to reduce odor and other gases on the farm scale. In our recent laboratory-scale study, the use of UV-A (a less toxic ultraviolet light, a.k.a. “black light”) and a special TiO2-based photocatalyst reduced concentrations of several important air pollutants (NH3, CO2, N2O, O3) without impact on H2S and CH4. Therefore, the objectives of this research were to (1) scale up the UV treatment to pilot scale, (2) evaluate the mitigation of odor and odorous volatile organic compounds (VOCs), and (3) complete preliminary economic analyses. A pilot-scale experiment was conducted under commercial poultry barn conditions to evaluate photocatalyst coatings on surfaces subjected to UV light under field conditions. In this study, the reactor was constructed to support interchangeable wall panels and installed on a poultry farm. The effects of a photocatalyst\u27s presence (photocatalysis and photolysis), UV intensity (LED and fluorescent), and treatment time were studied in the pilot-scale experiments inside a poultry barn. The results of the pilot-scale experiments were consistent with the laboratory-scale one: the percent reduction under photocatalysis was generally higher than photolysis. In addition, the percent reduction of target gases at a high light intensity and long treatment time was higher. The percent reduction of NH3 was 5–9%. There was no impact on H2S, CH4, and CO2 under any experimental conditions. N2O and O3 concentrations were reduced at 6–12% and 87–100% by both photolysis and photocatalysis. In addition, concentrations of several VOCs responsible for livestock odor were reduced from 26 to 62% and increased with treatment time and light intensity. The odor was reduced by 18%. Photolysis treatment reduced concentrations of N2O, VOCs, and O3, only. The initial economic analysis has shown that LEDs are more efficient than fluorescent lights. Further scale-up and research at farm scale are warranted

Effects of UV-A Light Treatment on Ammonia, Hydrogen Sulfide, Greenhouse Gases, and Ozone in Simulated Poultry Barn Conditions

Gaseous emissions, a side effect of livestock and poultry production, need to be mitigated to improve sustainability. Emissions of ammonia (NH3), hydrogen sulfide (H2S), greenhouse gases (GHGs), and odorous volatile organic compounds (VOCs) have a detrimental effect on the environment, climate, and quality of life in rural communities. We are building on previous research to bring advanced oxidation technologies from the lab to the farm. To date, we have shown that ultraviolet A (UV-A) has the potential to mitigate selected odorous gases and GHGs in the context of swine production. Much less research on emissions mitigation has been conducted in the context of poultry production. Thus, the study objective was to investigate whether the UV-A can mitigate NH3, H2S, GHGs, and O3 in the simulated poultry barn environment. The effects of several variables were tested: the presence of photocatalyst, relative humidity, treatment time, and dust accumulation under two different light intensities (facilitated with fluorescent and light-emitting diode, LED, lamps). The results provide evidence that photocatalysis with TiO2 coating and UV-A light can reduce gas concentrations of NH3, CO2, N2O, and O3, without a significant effect on H2S and CH4. The particular % reduction depends on the presence of photocatalysts, relative humidity (RH), light type (intensity), treatment time, and dust accumulation on the photocatalyst surface. In the case of NH3, the reduction varied from 2.6–18.7% and was affected by RH and light intensity. The % reduction of NH3 was the highest at 12% RH and increased with treatment time and light intensity. The % reduction of NH3 decreased with the accumulation of poultry dust. The % reduction for H2S had no statistical difference under any experimental conditions. The proposed treatment of NH3 and H2S was evaluated for a potential impact on important ambient air quality parameters, the possibility of simultaneously mitigating or generating GHGs. There was no statistically significant change in CH4 concentrations under any experimental conditions. CO2 was reduced at 3.8%–4.4%. N2O and O3 concentrations were reduced by both direct photolysis and photocatalysis, with the latter having greater % reductions. As much as 6.9–12.2% of the statistically-significant mitigation of N2O was observed. The % reduction for O3 ranged from 12.4–48.4%. The results warrant scaling up to a pilot-scale where the technology could be evaluated with economic analyses

Emissions from Swine Manure Treated with Current Products for Mitigation of Odors and Reduction of NH3, H2S, VOC, and GHG Emissions

Odor and gaseous emissions from the swine industry are of concern for the wellbeing of humans and livestock. Additives applied to the swine manure surface are popular, marketed products to solve this problem and relatively inexpensive and easy for farmers to use. There is no scientific data evaluating the effectiveness of many of these products. We evaluated 12 manure additive products that are currently being marketed on their effectiveness in mitigating odor and gaseous emissions from swine manure. We used a pilot-scale system simulating the storage of swine manure with a controlled ventilation of headspace and periodic addition of manure. This dataset contains measured concentrations and estimated emissions of target gases in manure headspace above treated and untreated swine manure. These include ammonia (NH3), hydrogen sulfide (H2S), greenhouse gases (CO2, CH4, and N2O), volatile organic compounds (VOC), and odor. The experiment to test each manure additive product lasted for two months; the measurements of NH3 and H2S were completed twice a week; others were conducted weekly. The manure for each test was collected from three different farms in central Iowa to provide the necessary variety in stored swine manure properties. This dataset is useful for further analyses of gaseous emissions from swine manure under simulated storage conditions and for performance comparison of marketed products for the mitigation of gaseous emissions. Ultimately, swine farmers, the regulatory community, and the public need to have scientific data informing decisions about the usefulness of manure additives

Evaluating of Products for Mitigation of Odor and Reduction of NH3, H2S, GHG, and VOC Emissions from Swine Manure in Deep Pit Storage Structures

Odorous gas emissions from swine production are the unwanted by-product of farmers. Manure additive has a great potential to solve this problem. Manure additives are considered low-cost and user-friendly; they can be implemented without changing the current manure storage practices. The objective of this study was to evaluate the effectiveness of 12 current commercial manure additives on mitigating odor, ammonia (NH3), hydrogen sulfide (H2S), greenhouse gas (GHG), and volatile organic compounds (VOCs) from stored swine manure with pilot-scale setup by strictly following the recommended dosages and procedures from the product labels. Each product was tested for 2 months while gas and odor measurements were done weekly. At the end of the trials, manure properties and microbial communities were analyzed to determine whether manure additives impacting microbes in manure. Preliminary analyses indicate that there is no statistically significant reduction of any measured gas or odor emissions that could be associated with the tested products

Mitigation of Odor, NH3, H2S, GHG, and VOC Emissions With Current Products for Use in Deep-Pit Swine Manure Storage Structures

Odorous gas emissions from swine production have been a concern for neighbors and communities near livestock farms. Manure storage is one of the main sources of gaseous emissions. Manure additive products are marketed as a simple solution to this environmental challenge. Manure additives are user-friendly for producers and can be applied (e.g., periodically poured into manure) without changing the current manure storage structure. Little scientific data exist on how these products perform in mitigating gaseous emissions from swine manure. The research objective was to evaluate the effectiveness of 12 marketed manure additives on mitigating odor, ammonia (NH3), hydrogen sulfide (H2S), greenhouse gases (GHG), and odorous volatile organic compounds (VOCs) from stored swine manure. A controlled pilot-scale setup was used to conduct 8-week long trials using manufacturer-prescribed dosages of additives into swine manures. Manure was outsourced from three swine farms to represent a variety of manure storage types and other factors affecting the properties. Measured gaseous emissions were compared between the treated and untreated manure. None of the tested products showed a significant reduction in gaseous emissions when all (n = 3) manures were treated as replicates. Selected products showed a wide range of statistically-significant reduction and generation of gaseous emissions when emissions were compared in pairs of manure types from one farm. The latter observation highlighted the lack of consistent mitigation of gaseous emissions by manure additives. The results of this study do not warrant full-scale trials with the tested products

Effects of Treated Manure Conditions on Ammonia and Hydrogen Sulfide Emissions from a Swine Finishing Barn Equipped with Semicontinuous Pit Recharge System in Summer

Gaseous emissions from animal production systems affect the local and regional air quality. Proven farm-scale mitigation technologies are needed to lower these emissions and to provide management practices that are feasible and sustainable. In this research, we evaluate the performance of a unique approach that simultaneously mitigates emissions and improves air quality inside a barn equipped with a manure pit recharge system. Specifically, we tested the effects of summertime feeding rations (used by farmers to cope with animal heat stress) and manure management. To date, the pit recharge system has been proven to be effective in mitigating both ammonia (NH3; approximately 53%) and hydrogen sulfide (H2S; approximately 84%) emissions during mild climate conditions. However, its performance during the hot season with a high crude protein diet and high nitrogen loading into the pit manure recharge system is unknown. Therefore, we compared the emissions and indoor air quality of the rooms (240 pigs, ~80 kg each) equipped with a conventional slurry and pit recharge system. The main findings highlight the importance and impact of seasonal variation and diet and manure management practices. We observed 31% greater NH3 emissions from the pit recharge system (33.7 ± 1.4 g·head−1·day−1) compared with a conventional slurry system (25.9 ± 2.4 g·head−1·day−1). Additionally, the NH3 concentration inside the barn was higher (by 24%) in the pit recharge system compared with the control. On the other hand, H2S emissions were 55% lower in the pit recharge system (628 ± 47 mg·head−1·day−1) compared with a conventional slurry pit (1400 ± 132 mg·head−1·day−1). Additionally, the H2S concentration inside the barn was lower (by 54%) in the pit recharge system compared with the control. The characteristics of the pit recharge liquid (i.e., aerobically treated manure), such as the total nitrogen (TN) and ammonium N (NH4-N) contents, contributed to the higher NH3 emissions from the pit recharge system in summer. However, their influence on H2S emissions had a relatively low impact, i.e., emissions were still reduced, similarly as they were in mild climate conditions. Overall, it is necessary to consider a seasonal diet and manure management practices when evaluating emissions and indoor air quality. Further research on minimizing the seasonal nitrogen loading and optimizing pit recharge manure characteristics is warranted.This article is published as Wi, J.; Lee, S.; Kim, E.; Lee, M.; Koziel, J.A.; Ahn, H. "Effects of Treated Manure Conditions on Ammonia and Hydrogen Sulfide Emissions from a Swine Finishing Barn Equipped with Semicontinuous Pit Recharge System in Summer." 11 Atmosphere (2020): 713. DOI: 10.3390/atmos11070713. Posted with permission. </p

Evaluation of Semi-Continuous Pit Manure Recharge System Performance on Mitigation of Ammonia and Hydrogen Sulfide Emissions from a Swine Finishing Barn

In this research, for the first time, we present the evaluation of a semi-continuous pit manure recharge system on the mitigation of ammonia (NH3) and hydrogen sulfide (H2S) emissions from a swine finisher barn. The pit recharge system is practiced on many swine farms in the Republic of Korea, primarily for improving air quality in the barn. It consists of an integrated waste management system where the fraction of stored manure is pumped out (10&#215; of the daily production of manure, 3&#215; a day); solids are separated and composted, while the aerobically treated liquid fraction is then returned to the pit. We compared emissions from two 240-pig rooms, one equipped with a pit recharge system, and the other operating a conventional slurry pit under the slatted floor. Mean reduction of NH3 and H2S emissions were 49 &#177; 6% and 82 &#177; 7%, respectively, over 14 days of measurements. The removal efficiency of H2S was higher than NH3, likely because the pH of aerobically treated liquid manure remained slightly above 8. More work is warranted to assess the N balance in this system and the emissions of odor and greenhouse gasses (GHGs). It is also expected that it will be possible to control the NH3 and H2S removal rates by controlling the nitrification level of the liquid manure in the aerobic treatment system

Evaluation of Semi-Continuous Pit Manure Recharge System Performance on Mitigation of Ammonia and Hydrogen Sulfide Emissions from a Swine Finishing Barn

In this research, for the first time, we present the evaluation of a semi-continuous pit manure recharge system on the mitigation of ammonia (NH3) and hydrogen sulfide (H2S) emissions from a swine finisher barn. The pit recharge system is practiced on many swine farms in the Republic of Korea, primarily for improving air quality in the barn. It consists of an integrated waste management system where the fraction of stored manure is pumped out (10× of the daily production of manure, 3× a day); solids are separated and composted, while the aerobically treated liquid fraction is then returned to the pit. We compared emissions from two 240-pig rooms, one equipped with a pit recharge system, and the other operating a conventional slurry pit under the slatted floor. Mean reduction of NH3 and H2S emissions were 49 ± 6% and 82 ± 7%, respectively, over 14 days of measurements. The removal efficiency of H2S was higher than NH3, likely because the pH of aerobically treated liquid manure remained slightly above 8. More work is warranted to assess the N balance in this system and the emissions of odor and greenhouse gasses (GHGs). It is also expected that it will be possible to control the NH3 and H2S removal rates by controlling the nitrification level of the liquid manure in the aerobic treatment system.This article is published as Wi, Jisoo, Seunghun Lee, Eunjong Kim, Myeongseong Lee, Jacek A. Koziel, and Heekwon Ahn. "Evaluation of Semi-Continuous Pit Manure Recharge System Performance on Mitigation of Ammonia and Hydrogen Sulfide Emissions from a Swine Finishing Barn." Atmosphere 10, no. 4 (2019): 170. DOI: 10.3390/atmos10040170. Posted with permission.</p