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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.
1

An integrated treatment system for liquid swine manure.

Fernandes, Leta F. January 1988 (has links)
No description available.
2

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.
3

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.
4

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.
5

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.
6

Reducing ammonia volatilization from liquid hog manure by using organic amendments

Subair January 1995 (has links)
Considerable amounts of N can be lost from manure through NH$ sb3$ volatilization. Four laboratory studies were conducted to evaluate the effects of organic amendments on reducing NH$ sb3$ loss from liquid hog manure (LHM). The organic amendments used in these studies were sugar, sawdust and paper products including filter paper (FP), paper bag (PB), newsprint (NP) and pulp sludge (PS). Generally, organic amendments had significant effects on reducing NH$ sb3$ loss from LHM and their effectiveness increased with increasing addition rates. Sugar addition of 3% or higher could eliminate the NH$ sb3$ loss, depending on LHM properties and incubation conditions. The effectiveness of sugar, especially lower rates, decrease with time. The unrecovered NH$ sb4$ loss increased and manure pH decreased with the increase in sugar rates, indicating that the reduction in NH$ sb3$ loss due to sugar addition may have been caused by N immobilization and pH reduction. Sawdust addition reduced the NH$ sb3$ loss by as much as 20% compared to the control. The mixture of 5.5% sugar and 5% sawdust was more effective in reducing NH$ sb3$ loss than 5.5% sugar alone but, lower sugar rates were not similarly affected by sawdust addition. Addition of 5% FP, PB, NP and PS resulted in the decrease in NH$ sb3$ loss by as much as 40, 47, 37 and 29% in comparison to the non-amended manure. The unrecovered NH$ sb4 sp+$ loss and the loss of added C increased with increasing C addition, indicating that N immobilization may be the cause of the decrease in NH$ sb3$ due to paper product additions. (Abstract shortened by UMI.)
7

Lignosulphonate amended liquid hog manure : ammonia volatilization and nitrogen availability

Zou, Guangyong January 1994 (has links)
Ammonia (NH$ sb3$) volatilization from manure can represent a major process through which nitrogen (N) is lost from the soil-plant-animal system. Reductions in NH$ sb3$ volatilization have significance both in economic and ecological aspects. Calcium lignosulphonate (CaLS), an acidic, water-soluble organic waste product of the pulp and paper industry, is expected to reduce NH$ sb3$ volatilization from liquid hog (Sus scrofa dometicus) manure (LHM) and consequently increase fertilizer value of LHM. Reduction of NH$ sb3$ loss from LHM was studied using added CaLS at 0, 6% 12% and 18% CaLS (based on fresh LHM weight) during 21 d incubation. Cumulative losses of NH$ sb3$-N ranged between 0 to 46% of initial total N. Compared to untreated LHM, the 6% CaLS treatment control N loss for 7 d and promoted N loss thereafter, while 12% and 18% CaLS treatments effectively reduced N losses throughout the 21 d incubation period. The N availability and the effect of CaLS-LHM mixtures on ryegrass (Lolium multiform Lamb.) growth were assessed on two soils mapped as St. Amable (sandy loam) and Ste. Rosalie (clay loam) from eastern Canada. Calcium lignosulphonate showed adverse effect on ryegrass plant growth, while as an amendment it did not reduce the effectiveness of LHM-N for ryegrass dry matter yield (DMY) and chemical composition at application rate up to 12% of LHM for the sandy loam soil and 18% of LHM for the clay loam soil. These findings suggested that CaLS may be used as an amendment for controlling N losses from animal manures.
8

Field estimates of ammonia volatilization from swine manure by a simple micrometeorological technique

Gordon, Robert J. (Robert James), 1940- January 1988 (has links)
No description available.
9

Lignosulphonate amended liquid hog manure : ammonia volatilization and nitrogen availability

Zou, Guangyong January 1994 (has links)
No description available.
10

Field estimates of ammonia volatilization from swine manure by a simple micrometeorological technique

Gordon, Robert J. (Robert James), 1940- January 1988 (has links)
No description available.

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