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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.
31

Differential optical absorption spectroscopy (DOAS) measurements of atmospheric ammonia in the mid-ultraviolet from a dairy concentrations, emissions, and modeling /

Rumburg, Brian Paul, January 2006 (has links) (PDF)
Thesis (Ph.D.)--Washington State University, May 2006. / Includes bibliographical references (p. 162-170).
32

Avaliação dos resíduos sólidos e líquidos num sistema de abate de bovinos /

Morales, Marina Moura, 1981- January 2006 (has links)
Orientador: Jorge de Lucas Junior / Banca: Sergio Campos / Banca: Mônica Sarolli S. de Mendonça Costa / Resumo: O Brasil apresenta grandes potencialidades na produção de alimentos, porém as formas empregadas para atendimento desta demanda têm levado ao aumento da geração de resíduos, fato que justifica o estudo de práticas de reciclagem, tais como a compostagem e a biodigestão anaeróbia desses materiais, pois, além da agregação de valor devido à transformação de resíduos potencialmente poluidores em adubo orgânico e geração de energia (biogás) ainda contribui para um saneamento eficaz. No desenvolvimento deste trabalho foi realizada a caracterização dos resíduos produzidos no sistema de abate de bovinos em dois ensaios: avaliação dos resíduos sólidos (conteúdo ruminal) e caracterização dos resíduos líquidos (água residuária). No primeiro ensaio, avaliação dos resíduos sólidos, foi realizada a compostagem, durante a qual monitorou-se diariamente a temperatura das leiras confeccionadas com o resíduo de abatedouro de bovinos. Foram avaliadas quatro leiras, divididas em dois ciclos: verão e outono. Para tanto, foram avaliados os teores de sólidos totais (ST) e de sólidos voláteis (SV), carbono orgânico (C) e quantificação dos teores nitrogênio (N), fósforo (P), potássio (K), cálcio (Ca), magnésio (Mg), cobre (Cu), ferro (Fe), manganês (Mn), zinco (Zn) e sódio (Na). Com os resíduos sólidos in natura previamente secos, foram determinados o poder calorífico superior com agregação de sebo, também produzido no processo nas concentrações de 0%, 10%, 20%, 30% e 40%. No segundo ensaio, caracterização dos resíduos líquidos, realizaram-se coletas e análise de amostras compostas de oito pontos do processo de tratamento de resíduos do abatedouro: antes do flotador, depois do flotador, antes da peneira, depois da peneira, efluente do biodigestor 1, efluente do biodigestor 2, afluente das lagoas de polimento e efluentes das lagoas de polimento. / Abstract: Brazil has feed production high potential, but the way used to attend its demand had led to an increasing of generated residues. This fact justifies the recycling practices study like composting and anaerobic biodigestion. More over value aggregation due the residues potentially pollutants transformation to organic fertilizers and energy (biogas) still contributes to an efficient sanitation.'During the experiment the bovine slaughter residues characterization was done in two experiments: solid residues evaluation (ruminal content) and liquid residues characterization (residual water). At first experiment a composting was done using solid residues from cattle slaughter, which the pile temperature was checked daily. Four piles were analyzed, divided in two cycles: summer and autumn. Was analyzed Total Solids (TS) Volatile Solids (VS), Organic Carbon (C), Nitrogen (N), Phosphorus (P), Potassium (K), Calcium (Ca), Magnesium (Mg), Cupper (Cu), Iron (Fe) Manganese (Mn), Zinc (Zn), and Sodium (Na). With in natura residues priory dried, superior calorific power was determined adding fat also produced in the slaughtering process, at 0%, 10%, 20%, 30% and 40% concentrations. The second experiment was done collecting eight small samples per sample at the residue treatment process: before floater, after floater, before sieve, after sieve, biodigestor effluent 1, biodigestor effluent 2, polishing pond affluent, and polishing pond effluent. TS, VS, pH, Chemical Oxygen Demand, (COD) Biochemical Oxygen Demand (BOD), N, P, K, Ca, Mg, Co, Fe, Cu, Zn, Mn elements quantification plus affluent and polish pond effluent Na and Ni content. Viable helminth eggs, Salmonella sp., total and fecal coliform were analyzed in the polish pond affluent and effluent. About the autumn compost piles, they had 10% more volume reduction than the summer ones. The average temperatures were 40ºC during summer and 33ºC during autumn. / Mestre
33

Impact of Animal Waste Best Management Practices on the Bacteriological Quality of Surface Water

Cook, Mary Nicole Jr. 12 June 1998 (has links)
An extensive 10 year monitoring project was initiated in 1986 to examine the effects of a combination of BMPs on surface water quality within a watershed with complex land use. This research specifically examined bacteriological water quality and BMP impacts. Bimonthly grab samples were collected from four surface water monitoring stations, including the watershed outlet, and analyzed for fecal coliform, total coliform, and fecal streptococcus bacteria. Other data compiled from the watershed included hydrologic, meteorologic, geologic and land use data, also collected on a regular basis. Data were collected continuously throughout the project, and thus included both pre- and post-BMP monitoring data. BMP implementation included animal waste storage facilities, nutrient management plans, conservation tillage, alternative water sources for livestock, fences, vegetative filter strips, runoff diversions, and others. Statistical analysis of the monthly precipitation data indicated no significant difference in rainfall quantity between the pre-BMP and post-BMP monitoring periods. Monthly runoff totals increased 39% from the pre- to the post-BMP periods at the watershed outlet. Increases at all of the subwatershed outlets occurred as well (B, 40%; C, 38%; D, 16%). Statistical analysis did not show a significant difference in runoff between the two monitoring periods, except at station C, where post-BMP runoff was significantly greater than the values measured during the pre-BMP period. Overall reductions in the mean (geometric) levels of total coliform, fecal coliform and fecal streptococcus bacteria observed at the watershed outlet were 81%, 30% and 76%, respectively. Both parametric and nonparametric statistical analysis techniques were applied to the bacteriological data. Regression analysis of the fecal coliform data showed an increase during the pre-BMP period followed by a decrease post-BMP and a statistically significant difference between the two periods (p=0.004). No trends were evident. Only one of the four stations had a statistical difference between pre- and post-BMP fecal streptococcus data, however, a downward trend was present at every station. No statistically significant difference between the pre- and post-BMP total coliform bacteria was evident, although a downward trend was present at the watershed outlet. These findings indicate that the combination of BMPs implemented in the watershed were effective in reducing the loss of fecal bacteria to receiving streams via overland flow. / Master of Science
34

Quantitative measurement and sensory evaluation of dairy waste odor /

Ifeadi, Christopher Ngozi January 1972 (has links)
No description available.
35

Biochemical changes in the fermentation bedding of the "pig-on-litter"method of pig farming: with special emphasison biodegradation of nitrogen compounds and odour production

周厚華, Chaw, Donna. January 1996 (has links)
published_or_final_version / Zoology / Doctoral / Doctor of Philosophy
36

Livestock waste and sewage sludge for growing local leafy vegetables /

Hui, Ming-leung. January 1996 (has links)
Thesis (M. Phil.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 135-147).
37

A study on the livestock waste control scheme

Lam, Wing-yiu., 林榮耀. January 1997 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
38

A review of livestock waste management in Hong Kong

Lam, Chung-wai., 林頌偉. January 2001 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
39

Utilisation of animal wastes and sewage sludges and their subsequent effects on higher trophic levels in food chains.

January 1981 (has links)
by Cheung Yun Hing Richard. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1981. / Bibliography: leaves 182-206.
40

Bio-delipidation of pre-treated poultry slaughterhouse wastewater by enzymes from the wastewater isolates

Mbulawa, Siyasanga January 2017 (has links)
Thesis (Master of Engineering in Chemical Engineering)--Cape Peninsula University of Technology, 2017. / Pre-treatment of wastewater such as that from poultry slaughterhouses, which contains fats, oil,and grease (FOG) is necessary prior to the primary biological treatment of the wastewater to meet legislated discharge standards and to prevent environmental pollution. Physico- chemical pre-treatment is often applied to remove FOG in poultry slaughterhouse wastewater (PSW) before biological treatment. These pre-treatment methods, in particular physical pre- treatment systems, use synthetic chemicals, known to cause environmental contamination challenges, with FOG being inefficiently removed in certain instances. Biological techniques such as bio-delipidation using enzymatic catalysis for the pre-treatment of FOG-laden PSW could enhance the efficiency of the downstream biological treatment processes. This research focused on further bio-delipidation of PSW pre-treated with a dissolved air flotation system (DAF) for FOG removal using microbial lipases from bacterial strains isolated from the PSW itself. Bacterial strains (n = 2) isolated from the PSW and screened for their potential to produce lipases were found to have a higher bio-delipidation potential when compared to other isolates (n = 18). Both isolates were identified using 16s rRNA as Bacillus sp., i.e. both Bacillus cereus AB1 (BF3) and CC-1 (B3O). These isolates were used to produce lipases, whereby are sponse surface methodology (RSM) was used to optimise pH (4-8) and temperature (30-60°C) as critical production conditions. achieving an optimum lipase production was achieved, with activity of 11.25 U/mL at 60°C, a pH of8 for BF3, and 15.50U/mL at 45°C and pH of 8.8 for B3O respectively, after 72 hours of bioreactor operation. The enzymes produced from both isolates were partially purified using a Bio-Rad size exclusion chromatography column (Bio-Gel® P-60) prior to use in subsequent experiments. The presence and activity of lipase were further determined using p-nitrophenyl acetate (p- NPA) as a substrate with the functionality of the semi-purified enzymes being characterized by optimizing the conditions in which the enzymes were required to function. Lipase activity was enhanced by Mg2+ while Fe2+, Na+, K+, Ca2+ were observed to have an inhibitory effect on the enzymes from both strains. Similarly, reduced stability of the lipases in organic solvents, namely toluene, methanol, and isopropanol, was also established. Additionally, detergents, Triclosan (TCS) (5-chloro-2-(2,4-dichlorophenoxy-phenol) and trichlorocarbonilide (3,4,4- trichlorocarbonilide)(TCC), usually found in PSW as antimicrobial and disinfectant agents to sanitise poultry product processing facilities, were used assess the activity of the enzyme in their presence at a concentration of 30% (v/v) (although these anti- microbial agents are used in minute quantities in cleaning products). The lipases from isolate BF3 maintained an activity of 91.43% and 81.36% in the presence of TCS and TCC, while that of B3O enzyme had 85.32% and 73.91% acitivity, when compared to the reference (control) experiments. The bio-delipidation efficacy was studied under varying pH and temperature conditions using DAF pre-treated PSW, observing a further removal efficiency of fatty acids from the protein- laden PSW at different pH and temperature. Bio-delipidation was found to be largely influenced by pH, as a pH below 7 and above 10 at 40°-45°C, calculated in the bio- delipidation efficiency reduction to below 50%. The temperature range mentioned, i.e 40°- 45°C, had a positive effect on further deffating of the protein-rich DAF pre-treated PSW, as high removal efficiency was observed at this temperature range. This could be due to the characteristic of the enzymes used,or the formation of stable FOG agglomerates and/oremulsion. Overall, a DAF effluent containing residual FOG and proteins was bio-delipidated effectively using enzymes from the PSW isolates, achieving further removal of FOG and proteins by 64.35% to 80.42%, culminating in tCOD reduction and reduced PSW turbidity, further resulting in improved wastewater quality characteristics meeting disposal standards. This study demonstrated that sequential DAF pre-treated PSW bio-delipidation has the potential to enhance the efficiency of downstream biological anaerobic treatment processes for PSW by further reducing residual FOG from a DAF system.

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