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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Characterization of aging bovine manure in relation to stable fly (Diptera: muscidae) adult and larval presence

Haas, Merrilee Susan. January 1986 (has links)
Call number: LD2668 .T4 1986 H32 / Master of Science / Entomology
72

Experimental manure handling systems for reducing airborne contamination

Stewart, Karen 05 January 2005
A laboratory was built at Prairie Swine Centre Inc. (PSCI) to study air quality in swine barns and its effect on pigs and people. The first focus of that research program was to design and test a manure handling system to control the air contamination from the excreta. The goal was to get close to zero air contamination from manure with these systems, in order to measure the contamination from other sources, and to also have a range of contamination levels for future health and productivity testing. Two manure handling systems were designed and tested: a washing gutter system with pressurized heated wash water periodically directed across the dunging area, and a washed inclined conveyor belt used directly as a dunging area. Ammonia emissions were used as a measure of the air contamination originating from the excreta in two experimental chambers. Ammonia originates only from the manure and is released quickly from any manure (especially urine) in contact with the air. Both systems were tested with 30 kg pigs at running time intervals of 30, 60 and 120 minutes. Trials lasted one week, with three trials completed at each frequency. The average ammonia emissions from the washing gutter and the conveyor belt systems were 48.7 mg day-1 kgpig-1 and 57.0 mg day-1 kgpig-1, respectively. Even though these emissions were 38% and 47% lower than previous observations from grower-finisher rooms with a pit plug design in the same swine building, both systems failed to give the desired close-to-zero contamination. This means another system will have to be found to totally eliminate air contamination from manure in the chambers when testing for the origin of the individual contaminants. There were no differences at a statistically significant level (P>0.05) between the ammonia emissions from the two manure handling systems or the three frequencies tested. However, the washing gutter system was simpler and easier to run, and is recommended for future studies dealing with the effects of different ranges of air quality on pigs and people.
73

Solid-state anaerobic digestion for integrated ethanol production

Lung, Patricia 09 November 2011
Anaerobic digestion (AD) is a biochemical process consisting of the microbiological conversion of organic materials for the purpose of generating biogas. Biogas is typically composed of 50 to 70% methane (CH4) and 50 to 30% carbon dioxide (CO2) with trace amounts of other compounds. Anaerobic digestion technology is a bioprocessing technology that has the potential to be integrated into an ethanol facility to further capture energy, in the form of methane gas, for use in a combined heat and power (CHP) generator or for integration into the natural gas pipeline grid after undergoing an upgrading process. The most simplistic design of an AD system is the solid state digester (SSD) which is able to process very high solids content materials (greater than 15% solids). A SSD has the potential to be utilized as a manure management system in a beef cattle feedlot and it has the potential to integrate seamlessly into a combined ethanol- feedlot operation to capitalize on the eco-cluster concept in bioenergy production. This thesis investigates the biogas and digestate composition seen from four material blends in a solid-state digester (SSD) system operated as a batch reactor. Wet distiller grains (WDG) from a grain ethanol process and cattle manure were the substrates investigated. To assess the biogas composition the system was operated over a period of time to achieve a quasi steady state within the microbial population to maximize the CH4 concentration in the biogas composition. To assess the robustness of the microbial population within each substrate blend, the biogas concentrations were measured over three cycle periods where a portion of the used substrate was replaced with an equal amount of fresh substrate. The digestate composition was analyzed at the end of each of the cycles and compared with the raw substrate to determine changes in solids and nutrient values. The biogas production calculated in this study determined 0.17, 0.21, 0.18, and 0.12L per gram (VS) within 100% WDG, 75%WDG and 25% manure, 25% WDG and 75% manure and the 100% manure substrate (Group 1 through 4) respectively, averaged over all three digestion cycles. At the end of three cycles of digestion the biogas within the substrate blend containing 25% WDG and 75% manure (Group 3) achieved a measured CH4 concentration of 49% and the biogas within the 100% manure substrate (Group 4) achieved a 59% concentration of CH4. The duration for each of Group 3 and Group 4 to achieve the production of viable biogas was 100 and 90 days of operation respectively. Thus it can be concluded that a SSD system start up duration will be between three and four months in duration. The gas data gathered in this research study indicates Group 3 had the most robust methanogenic culture established as it has the lowest overall N2 and CO2 concentration detected in the biogas, and the most consistent performance of CH4 production during each cycle. The investigation conducted on the nutrient data gathered in this research supports the conclusion drawn from the gas data regarding the overall methanogenic performance of the substrate blends. The nutrient data for Group 3 maintained an average carbon to nitrogen (C:N) ratio of 25:1 over all three digestion cycles. The nitrogen, phosphorous, potassium, and sulphur components of the manure fertilizer value were maintained through the digestion process of this investigation thus typical manure application rate calculations are applicable when field applying digestate.
74

Investigation of potential application of nanoparticles in reducing gas and odour emission from swine manure slurry

Asis, Daisy Abraham 09 July 2008
The objective of this research was to determine the effectiveness of nanoparticles for reducing gas and odour emissions from swine manure slurry using three deployment methods: headspace gas filtration, mixing with manure slurry and spraying into the headspace of manure slurry. <p> Filtering manure gas through the zinc oxide (ZnO) filter bed at a flow rate of 500 mL/min reduced ammonia (NH3), hydrogen sulphide (H2S) and odour concentrations by 74 to 99%. Methane (CH4) and carbon dioxide (CO2) concentrations of the filtered manure gas were decreased by 14% and 18%, respectively. Mixing ZnO into the manure slurry significantly reduced odour concentration by 79% and the hedonic tone was improved by 25% at one day after treatment application. Concentrations of CH4 and H2S were reduced by 54% and 98%; however concentrations of NH3 and nitrous oxide (N2O) were increased by 31% and 3%, respectively. Even though mixing of ZnO into the slurry influenced the gas and odour concentration, manure properties such as ammonia as N, TKN, P, K, S, Na, Ca, Mg, Cu, Fe, Mn, Z, total solids, % moisture, pH and EC were not changed except for an increase of 0.2 in pH value. Spraying tungsten oxide (WO3) into the headspace of manure slurry decreased the odour and CO2 concentration by 31 and 10%, but the reduction was not statistically significant (P>0.05).<p>Among the three deployment methods, filtration and mixing methods using ZnO were able to reduce NH3, H2S, and odour concentration. However, surface reactions between the manure gas components and nanoparticles should be investigated to increase the effectiveness of the treatment application. Likewise, knowing these reactions will facilitate the identification and manipulation of factors that influence the effectiveness of the deployment method. Economic, environmental and health assessment should be done to determine the feasibility and overall impact of using nanotechnology in reducing gas and odour emission to the swine industry.
75

Control of hydrogen sulphide, ammonia and odour emissions from swine barns using zinc oxide nanoparticles

Alvarado, Alvin Ceniza 02 September 2011
Application of zinc oxide (ZnO) nanoparticles was evaluated as a possible measure to mitigate the levels of hydrogen sulphide (H2S), ammonia (NH3) and odour in swine facilities. Two deployment techniques were investigated: direct mixing of zinc oxide nanoparticles into the slurry, and filtration with nanoparticles as filtering media for the manure gases. The overall goal of this work was to determine the impact of the treatments on hydrogen sulphide, ammonia and odour emissions, pig performance and manure characteristics as well as to assess the feasibility of the application of this technology in a typical swine barn. Semi-pilot scale tests were conducted to evaluate operational factors in open system conditions, the results of which showed that the mixing method required a particle-to-slurry ratio of 3 grams of zinc oxide per litre of slurry to control hydrogen sulphide and ammonia levels. Using the air filtration technique, a fluidized bed filter design with a 0.28 g/cm2 loading rate and rated at 0.5 m/s face velocity was found to be the most effective combination for controlling gas levels. Room-scale experiments were conducted in specially designed chambers to assess the effectiveness of the treatments under conditions that represent commercial swine production. The addition of zinc oxide nanoparticles into the manure achieved more than 95% reduction in hydrogen sulphide levels while no significant effects on ammonia concentrations were observed. Zinc oxide nanoparticles were persistent in maintaining low hydrogen sulphide levels up to 15 days after treatment application. On the other hand, the ventilation air recirculation system with a zinc oxide filter achieved significant reduction in both hydrogen sulphide and ammonia concentrations at the animal- and human-occupied zones. Neither treatment had any significant impact on pig performance and manure nutrient characteristics. Estimates of the cost of application of the treatments in a 100-head grow-finish room showed that employing the air filtration method amounted to around 3.8% of the average total cost of production, which was economically more feasible than the mixing method; however, various options can be pursued to further reduce the cost of application of both treatments.
76

Control of hydrogen sulphide, ammonia and odour emissions from swine barns using zinc oxide nanoparticles

Alvarado, Alvin Ceniza 02 September 2011 (has links)
Application of zinc oxide (ZnO) nanoparticles was evaluated as a possible measure to mitigate the levels of hydrogen sulphide (H2S), ammonia (NH3) and odour in swine facilities. Two deployment techniques were investigated: direct mixing of zinc oxide nanoparticles into the slurry, and filtration with nanoparticles as filtering media for the manure gases. The overall goal of this work was to determine the impact of the treatments on hydrogen sulphide, ammonia and odour emissions, pig performance and manure characteristics as well as to assess the feasibility of the application of this technology in a typical swine barn. Semi-pilot scale tests were conducted to evaluate operational factors in open system conditions, the results of which showed that the mixing method required a particle-to-slurry ratio of 3 grams of zinc oxide per litre of slurry to control hydrogen sulphide and ammonia levels. Using the air filtration technique, a fluidized bed filter design with a 0.28 g/cm2 loading rate and rated at 0.5 m/s face velocity was found to be the most effective combination for controlling gas levels. Room-scale experiments were conducted in specially designed chambers to assess the effectiveness of the treatments under conditions that represent commercial swine production. The addition of zinc oxide nanoparticles into the manure achieved more than 95% reduction in hydrogen sulphide levels while no significant effects on ammonia concentrations were observed. Zinc oxide nanoparticles were persistent in maintaining low hydrogen sulphide levels up to 15 days after treatment application. On the other hand, the ventilation air recirculation system with a zinc oxide filter achieved significant reduction in both hydrogen sulphide and ammonia concentrations at the animal- and human-occupied zones. Neither treatment had any significant impact on pig performance and manure nutrient characteristics. Estimates of the cost of application of the treatments in a 100-head grow-finish room showed that employing the air filtration method amounted to around 3.8% of the average total cost of production, which was economically more feasible than the mixing method; however, various options can be pursued to further reduce the cost of application of both treatments.
77

Solid-state anaerobic digestion for integrated ethanol production

Lung, Patricia 09 November 2011 (has links)
Anaerobic digestion (AD) is a biochemical process consisting of the microbiological conversion of organic materials for the purpose of generating biogas. Biogas is typically composed of 50 to 70% methane (CH4) and 50 to 30% carbon dioxide (CO2) with trace amounts of other compounds. Anaerobic digestion technology is a bioprocessing technology that has the potential to be integrated into an ethanol facility to further capture energy, in the form of methane gas, for use in a combined heat and power (CHP) generator or for integration into the natural gas pipeline grid after undergoing an upgrading process. The most simplistic design of an AD system is the solid state digester (SSD) which is able to process very high solids content materials (greater than 15% solids). A SSD has the potential to be utilized as a manure management system in a beef cattle feedlot and it has the potential to integrate seamlessly into a combined ethanol- feedlot operation to capitalize on the eco-cluster concept in bioenergy production. This thesis investigates the biogas and digestate composition seen from four material blends in a solid-state digester (SSD) system operated as a batch reactor. Wet distiller grains (WDG) from a grain ethanol process and cattle manure were the substrates investigated. To assess the biogas composition the system was operated over a period of time to achieve a quasi steady state within the microbial population to maximize the CH4 concentration in the biogas composition. To assess the robustness of the microbial population within each substrate blend, the biogas concentrations were measured over three cycle periods where a portion of the used substrate was replaced with an equal amount of fresh substrate. The digestate composition was analyzed at the end of each of the cycles and compared with the raw substrate to determine changes in solids and nutrient values. The biogas production calculated in this study determined 0.17, 0.21, 0.18, and 0.12L per gram (VS) within 100% WDG, 75%WDG and 25% manure, 25% WDG and 75% manure and the 100% manure substrate (Group 1 through 4) respectively, averaged over all three digestion cycles. At the end of three cycles of digestion the biogas within the substrate blend containing 25% WDG and 75% manure (Group 3) achieved a measured CH4 concentration of 49% and the biogas within the 100% manure substrate (Group 4) achieved a 59% concentration of CH4. The duration for each of Group 3 and Group 4 to achieve the production of viable biogas was 100 and 90 days of operation respectively. Thus it can be concluded that a SSD system start up duration will be between three and four months in duration. The gas data gathered in this research study indicates Group 3 had the most robust methanogenic culture established as it has the lowest overall N2 and CO2 concentration detected in the biogas, and the most consistent performance of CH4 production during each cycle. The investigation conducted on the nutrient data gathered in this research supports the conclusion drawn from the gas data regarding the overall methanogenic performance of the substrate blends. The nutrient data for Group 3 maintained an average carbon to nitrogen (C:N) ratio of 25:1 over all three digestion cycles. The nitrogen, phosphorous, potassium, and sulphur components of the manure fertilizer value were maintained through the digestion process of this investigation thus typical manure application rate calculations are applicable when field applying digestate.
78

Experimental manure handling systems for reducing airborne contamination

Stewart, Karen 05 January 2005 (has links)
A laboratory was built at Prairie Swine Centre Inc. (PSCI) to study air quality in swine barns and its effect on pigs and people. The first focus of that research program was to design and test a manure handling system to control the air contamination from the excreta. The goal was to get close to zero air contamination from manure with these systems, in order to measure the contamination from other sources, and to also have a range of contamination levels for future health and productivity testing. Two manure handling systems were designed and tested: a washing gutter system with pressurized heated wash water periodically directed across the dunging area, and a washed inclined conveyor belt used directly as a dunging area. Ammonia emissions were used as a measure of the air contamination originating from the excreta in two experimental chambers. Ammonia originates only from the manure and is released quickly from any manure (especially urine) in contact with the air. Both systems were tested with 30 kg pigs at running time intervals of 30, 60 and 120 minutes. Trials lasted one week, with three trials completed at each frequency. The average ammonia emissions from the washing gutter and the conveyor belt systems were 48.7 mg day-1 kgpig-1 and 57.0 mg day-1 kgpig-1, respectively. Even though these emissions were 38% and 47% lower than previous observations from grower-finisher rooms with a pit plug design in the same swine building, both systems failed to give the desired close-to-zero contamination. This means another system will have to be found to totally eliminate air contamination from manure in the chambers when testing for the origin of the individual contaminants. There were no differences at a statistically significant level (P>0.05) between the ammonia emissions from the two manure handling systems or the three frequencies tested. However, the washing gutter system was simpler and easier to run, and is recommended for future studies dealing with the effects of different ranges of air quality on pigs and people.
79

Investigation of potential application of nanoparticles in reducing gas and odour emission from swine manure slurry

Asis, Daisy Abraham 09 July 2008 (has links)
The objective of this research was to determine the effectiveness of nanoparticles for reducing gas and odour emissions from swine manure slurry using three deployment methods: headspace gas filtration, mixing with manure slurry and spraying into the headspace of manure slurry. <p> Filtering manure gas through the zinc oxide (ZnO) filter bed at a flow rate of 500 mL/min reduced ammonia (NH3), hydrogen sulphide (H2S) and odour concentrations by 74 to 99%. Methane (CH4) and carbon dioxide (CO2) concentrations of the filtered manure gas were decreased by 14% and 18%, respectively. Mixing ZnO into the manure slurry significantly reduced odour concentration by 79% and the hedonic tone was improved by 25% at one day after treatment application. Concentrations of CH4 and H2S were reduced by 54% and 98%; however concentrations of NH3 and nitrous oxide (N2O) were increased by 31% and 3%, respectively. Even though mixing of ZnO into the slurry influenced the gas and odour concentration, manure properties such as ammonia as N, TKN, P, K, S, Na, Ca, Mg, Cu, Fe, Mn, Z, total solids, % moisture, pH and EC were not changed except for an increase of 0.2 in pH value. Spraying tungsten oxide (WO3) into the headspace of manure slurry decreased the odour and CO2 concentration by 31 and 10%, but the reduction was not statistically significant (P>0.05).<p>Among the three deployment methods, filtration and mixing methods using ZnO were able to reduce NH3, H2S, and odour concentration. However, surface reactions between the manure gas components and nanoparticles should be investigated to increase the effectiveness of the treatment application. Likewise, knowing these reactions will facilitate the identification and manipulation of factors that influence the effectiveness of the deployment method. Economic, environmental and health assessment should be done to determine the feasibility and overall impact of using nanotechnology in reducing gas and odour emission to the swine industry.
80

Treatment of Ammonia in Air Streams by Biotrickling Filters

Wang, Chia-Hsi 17 July 2000 (has links)
Abstract Ammonia is a major odoriferous component in the vent gas of the fermentation process of poultry manure compost. To prevent environmental problems, it is full-scale and a lab-scale biotrickling filters (BTF) were used for treatment of ammonia in air streams. The full-scale BTF was constructed by reinforced concrete (inner size = 6 m square ¡Ñ 5 m height) with PVC plate packings (total volume =6 m square ¡Ñ 3 m height = 108 m3 , specific area = 100 m2/m3). Long-term (357 days) experimental results show that, in the conditions of gas empty-bed-retention time EBRT = 35-77 s, liquid-gas ratio L/G = 5-11 L/m3, and recirculation liquid pH = 6.5-6.8, 6.5-29.8 ppm (average 14.3 ppm) ammonia in the influent gas could be reduced to 0-2.0 ppm (average 0.66 ppm). Daily rates were supplementary water = 0.400 m3, discharge water = 0.360 m3, supplementary H3PO4 (85%) = 0.28 kg. With the average volumetric ammonia loading of 0.66 g NH3-N/m3h, the system could achieve an average nitrification efficiency of 62% without supplementary glucose. Ammonia removal efficiencies of over 90% were obtained with recirculation liquid pH¡Ø6.8, and below 22% with pH¡Ù7.33. The lab-scale BTF consisted of a set of two-stage-in-series biotrickling filters, an influent gas supply system, and a liquid recirculation system. Each stage of the biotrickling filter was constructed from a 20 cm ¡Ñ 200 cm (inside diameter ¡Ñ height) acrylic column packed with cokes (average diameter = 3.0 cm and specific area = 150 m2/m3) of 125 cm height. Experimental results indicate that a time of 30 days was required for development of biofilms for nitrification of the absorbed ammonia from the gas. Long-term (187 days) experimental results show that, in the conditions of EBRT = 7.25 s, L/G=7.7 L/m3, and liquid pH=6.65, 230 ppm ammonia in the influent gas could be reduced to 4.0 ppm. With the volumetric ammonia loading of less than 7.37 g NH3-N/m3h, the system could achieve ammonia removal and nitrification efficiencies of 98 and 94%, respectively, without supplementary glucose. However, with a loading of 13.1 g NH3-N/m3h, both decreased gradually due to a lake of carbon (glucose) source and an accumulation of nitrite and nitrate in the recirculation liquid.

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