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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.
41

Lodo de esgoto como matriz orgânica na formulação de fertilizante organomineral para a cultura da soja / Sewage sludge as an organic matrix in the organomineral fertilizer formulation for soybean cultivation

Rodrigues, Mayra Maniero 05 July 2019 (has links)
O lodo de esgoto é associado a altas concentrações de poluentes inorgânicos em amplitudes que podem inviabilizar o uso direto em solo agrícola, de acordo com os limites máximos normatizados pela legislação, cujo destino final são aterros sanitários que, apesar de ser uma alternativa de menor impacto ambiental, é uma prática onerosa e finita. Entretanto, esse material é rica fonte matéria orgânica, macro e micronutrientes para as plantas como boro, cobre, cobalto, ferro, manganês, molibdênio, níquel e zinco para as plantas, comumente deficientes em solos tropicais. Em nosso estudo, exploramos esse subproduto como matriz orgânica para a formulação de um fertilizante organomineral (FOM) como alternativa à adubação mineral convencional para a cultura da soja em solos de Cerrado, além de possíveis alterações na comunidade microbiana do solo. O experimento foi conduzido em casa de vegetação utilizando dois Latossolos Vermelhos distróficos de texturas distintas (argiloso e franco-argilo-arenoso), diferentes doses de aplicação de FOM (40%, 60%, 80%, 100% e 120%) em três formas físicas (granulada, peletizada e farelada), em comparação com a adubação mineral convencional com (M+Mi+S) e sem (M+S) os micronutrientes B e Zn, além do tratamento sem adubação (CT). O delineamento utilizado foi de blocos inteiramente casualizados. As plantas foram conduzidas até os 60 dias após o plantio (DAP) e foram avaliados os parâmetros fitotécnicos pertinentes a massa seca da parte aérea (MSPA), massa seca de raiz (MSR), altura de plantas, diâmetro do colmo e número de nódulos ativos. A análise química da parte aérea (macro e micronutrientes) foi utilizada para cálculo do teor de nutrientes acumulados no tecido vegetal. Para avaliar a atividade microbiana dos solos utilizou-se a respiração basal do solo (RBS), carbono da biomassa microbiana (C-BM) e atividade das enzimas urease, fosfatase ácida e β-glucosidase. Em ambos os solos, tanto o FOM em menores doses (40% e 60%) quanto os tratamentos minerais, apresentaram desempenhos fitotécnicos semelhantes entre si, bem como o acúmulo de nutrientes no tecido vegetal das plantas, exceto para os elementos P, K e B. Não foram observadas diferenças significativas no desenvolvimento das plantas e nos atributos microbiológicos que possam ser atribuídas as formas físicas do FOM. Embora a RBS tenha indicado aumento na atividade microbiana dos solos a partir da adição de doses crescentes de FOMs, isso não refletiu nos demais parâmetros fitotécnicos ou microbiológicos avaliados, indicando que a planta foi a principal moduladora do comportamento da comunidade microbiana e da dinâmica de nutrientes. Adicionalmente, as análises enzimáticas mostraram-se pouco efetivas diante de condições de estresse observadas neste estudo para gerar respostas em função dos tratamentos. Conclui-se que a utilização de lodo de esgoto como matriz orgânica na formulação de FOMs pode ser uma alternativa agronomicamente viável e sustentável à adubação mineral convencional para a fertilização da soja em solos de Cerrado. / Sewage sludge is associated with high concentrations of inorganic pollutants in amplitudes that may make direct use in agricultural soil unfeasible, in accordance with the maximum limits established by legislation, the final destination of which are sanitary landfills, which, despite being a lower impact alternative is an onerous and finite practice. However, this material is rich source organic matter, macro and micronutrients for plants such as boron, copper, cobalt, iron, manganese, molybdenum, nickel and zinc for plants, commonly deficient in tropical soils. In our study, we explored this by-product as an organic matrix for the formulation of an organomineral fertilizer (FOM) as an alternative to the conventional mineral fertilization for soybean cultivation in Cerrado soils, as well as possible changes in the soil microbial community. The experiment was conducted in a greenhouse using two different dystrophic Red Latosols of different textures (clayey and sandy loam), different doses of FOM application (40%, 60%, 80%, 100% and 120%) in three (M + Mi + S) and without (M + S) the micronutrients B and Zn, besides the treatment without fertilization (CT). The design was completely randomized blocks. The plants were harvested up to 60 days after planting (DAP) and the relevant plant breeding parameters were evaluated for aerial dry mass (MSPA), dry root mass (DMW), plant height, shoot diameter and number of nodules active. The chemical analysis of aerial part (macro and micronutrients) was used to calculate the nutrient content accumulated in the vegetal tissue. Soil microbial biomass (C-BM) and activity of the enzymes urease, acid phosphatase and β-glucosidase were used to evaluate soil microbial activity. In both soils, FOM at lower doses (40% and 60%) and mineral treatments presented similar phytotechnical performances as well as nutrient accumulation in the plant tissue of the plants, except for the elements P, K and B. No significant differences were observed in the development of the plants and in the microbiological attributes that can be attributed to the physical forms of FOM. Although RBS indicated an increase in microbial activity of the soils from the addition of increasing doses of FOMs, this did not reflect the other phytotechnical or microbiological parameters evaluated, indicating that the plant was the main modulator of microbial community behavior and nutrient dynamics. In addition, the enzymatic analyzes showed little effectiveness in the stress conditions observed in this study to generate responses depending on the treatments. It is concluded that the use of sewage sludge as an organic matrix in the formulation of FOMs can be an agronomically viable and sustainable alternative to conventional mineral fertilization for soybean fertilization in Cerrado soils.
42

Reduction of Pathogens in Biosolids in Mexico Using Solar Drying Beds

Dominguez Sanchez, Teodulo January 2005 (has links)
In this study, die-off patterns of helminth ova, fecal coliforms, and Salmonella spp. in biosolids were documented using three small-scale sand drying beds located in a greenhouse. Treatments involved tilling the biosolids with differing frequencies. The results indicate that the inactivation rate for helminth ova was 0.88, 0.55, and 0.22 eggs/4 g TS day-1 for the intensively-tilled, moderately-tilled, and control beds, respectively. Achievement of Class A criteria was only possible in the intensively-tilled bed by Day 70 of the experiment. Salmonella spp. were inactivated to Class A levels in 9 days for the intensively and moderately-tilled beds. Regrowth of Salmonella spp. occurred thereafter in all beds, but high levels were seen only in the control bed. Fecal coliforms reached Class A criteria late in the experiment. Tilling treatments enhanced the inactivation rate of helminth ova and offer a potentially cost-effective method of pathogen reduction.
43

Aspects of Measuring Mass Balances of Endocrine Disrupting Compounds through Wastewater Treatment

Teske, Sondra Sue Gery January 2009 (has links)
Ecological impacts of natural estrogens and xenoestrogens in treated wastewater include altered sexual development and sex ratios among continuously exposed organisms. The primary sources of estrogenic activity in wastewater are natural estrogens such as estrone, 17β-estradiol and estriol and synthetic compounds like 17α- ethinylestradiol, alkylphenols and alklphenol ethoxylates. Precursors in raw wastewater can yield estrogenic intermediates during wastewater treatment. All these compounds can be destroyed by biochemical processes conventional wastewater treatment processes, suggesting that conventional processes can be optimized for removal of estrogenic activity from wastewater. Sorption to sludges derived from wastewater treatment affects the fates of hydrophobic xenoestrogens such as nonylphenol, in part because the biodegradability of sorbed contaminants is limited. It may also be possible to tailor sludge stabilization processes to remove trace contaminants, including estrogens. For example, there are significant differences in the efficiencies of aerobic and anaerobic digestion for destruction of alkylphenols and probably other estrogenic compounds with aromatic moieties. Because advanced wastewater treatment is not economically feasible for most communities, there is ample incentive to develop accurate relationships between operational parameters and removal of estrogenic compounds during secondary wastewater treatment. Large quantities of polybrominated diphenyl ethers (PBDEs) have been used as flame retardants in clothing and plastic products since the 1970s. A small fraction of the PBDEs in manufactured products subsequently enters municipal wastewater. The resistance of these compounds to chemical and biochemical transformations provides opportunities for accumulation in sediments. Balances developed for PBDE congeners indicate that conventional wastewater treatment processes and soil infiltration of treated wastewater in recharge operations do not discriminate significantly among the major congeners in commercially available PBDE products. Accumulation of PBDEs at near part-per-million levels was measured in the sediments at the Sweetwater Recharge Facility in Tucson, Arizona, during 10-15 years of operation. Half times for loss of major PBDE congeners from sediments were decades or longer. Local agricultural soils amended with biosolids over a 20-year period showed similar accumulation of PBDEs. The widespread use of PBDEs in commercial products, compound persistence and toxicity indicate that additional effort is warranted to better understand fate-determining processes for PBDEs in the environment.
44

SOIL PHOSPHORUS DYNAMICS UNDER ANNUAL OR SINGLE APPLICATIONS OF ALKALINE TREATED BIOSOLIDS

Shu, Weixi 14 April 2014 (has links)
Land application of biosolids as a soil fertility amendment is an alternative to traditional disposal methods. The influence of annual Alkaline Treated Biosolids (ATB) land application on phosphorus (P) dynamics in acidic soils needs to be better understood for more efficient P management. This study examines plant uptake, plant available, soil total phosphorus (P) content and potential P accumulation as a function of rate and frequency of application of an ATB amended to an agricultural soil over four years. The results suggest that applying high rates of ATB annually can increase the soil pH, Mehlich 3 and water extractable P, and crop P uptake in an acidic agricultural soil. No significant soil P accumulation was observed and P related environmental concerns were limited in this study. Potential soil P accumulation and higher P loss needs to be considered with annual high ATB rates application over a longer period study. / N/A
45

Biossólidos como fertilizantes de água para produção de plâncton / Biosolids as water fertilizer for plankton production

Cunha, Patrícia de Souza Lima 18 June 2008 (has links)
Made available in DSpace on 2015-03-26T13:54:42Z (GMT). No. of bitstreams: 1 texto completo.pdf: 533448 bytes, checksum: 49f2ee48cccb1d75643f0ce9c20929e8 (MD5) Previous issue date: 2008-06-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Aiming to evaluate the use of biosolid as a water fertilization strategy in the production of Daphnia sp., were conducted three experiments in the Fish Nutrition Laboratory of the Department of Animal Science of the Federal University of Viçosa (UFV). The first experiment, conducted during February and March 2008, to last for thirteen days, aimed to evaluate the use of different fertilizers - dicalcium phosphate (DF), biosolid (BS) and feces of quail (FQ). Were used 24 tanks of asbestos cement with useful volume of 100 L each, distributed in a completely randomized design, with four treatments (the three fertilizers and a control treatment without fertilization - WF) and six repetitions. As control variables were assessed the production of Daphnia sp. and the following water quality parameters: chlorophyll-a, electrical conductivity, pH, dissolved oxygen, temperature, ammonia nitrogen and organic nitrogen, total phosphorus and total hardness. The weight of the biomass of Daphnia sp. was measured at the end of the experiment (day 13). The control parameters of water quality were measured at three times during the experimental period: the first, eighth and thirteenth day. The maximum weight of the biomass of Daphnia sp. was found in tanks fertilized with FQ (35.6 grams), followed by the BS (16.8 grams), WF (6.8 g) and DF (5.2 g). There was a correlation between the values of chlorophyll-a and the weight of the biomass of Daphnia sp., which will very likely reflects interactions between phytoplankton and zooplankton communities. The results suggest that biosolids can be successfully used as water fertilizer, for production of phytoplankton and, consequently, of zooplankton. In the second experiment, carried out from February and March 2008, sought to evaluate the application of different levels of biosolids. Were used 25 tanks of asbestos cement with useful volume of 100 L each, distributed in a completely randomized design with five treatments (four levels of biosolids - 25 g, 50 g, 75 g and 100 g and a control treatment without fertilization) and five repetitions. The control variables and the sampling plan were the same as the first experiment. The weight of the biomass of Daphnia sp. was measured at the end of the experiment (day 13). The control parameters of water quality were measured at three times over the experimental period: first, eighth and thirteenth day. The average weight of biomass of Daphnia sp. found in the tanks were: 16.51 g to 100 g of biosolids; 14.63 g to 75 g of biosolids; 14.10 g to 50 g of biosolids; 12.85 g to 25 g of biosolids and 5.80 g in tank without fertilization. The results suggest that biosolids can be successfully used as water fertilizer for production of phytoplankton and, consequently, of zooplankton. The application of increasing quantities of biosolid not committed water quality to the point of making it unsuitable for the cultivation of aquatic organisms. However, despite the growing production of phytoplankton in line with increasing levels of biosolids, the production of Daphnia sp. tended to stabilize itself from the application of 50 grams of biosolids. The third experiment, conducted from March to April of 2008 with duration of fourteen days, involved the use of biosolid with different settings of NPK. Were used 25 tanks of cement and asbestos previous designs, with five treatments (five levels of NPK in 50 g of biosolids) and five repetitions. The control variables and the sampling plan was essentially the same of previous experiments, but measuring up nitrate and soluble phosphorus in place of organic nitrogen and total phosphorus. The application of biosolids with different formulations of NPK not compromised water quality to the point of making it unsuitable for the cultivation of aquatic organisms. However, despite the growing production of phytoplankton in line with increasing levels of phosphorus in the formulation of fertilizers, the weights average of Daphnia sp. biomass found in the tanks, around 10 grams, not statistically different for different treatments. In short, the results suggest that biosolids can be successfully used as water fertilizer for production of phytoplankton and zooplankton. / Objetivando-se avaliar a utilização do biossólido como estratégia de fertilização de água na produção de Daphnia sp., foram conduzidos três experimentos no Laboratório de Nutrição de peixes do Departamento de Zootecnia da Universidade Federal de Viçosa (UFV). O primeiro experimento, conduzido no período de fevereiro e março de 2008, com duração de treze dias, teve como objetivo avaliar a utilização de diferentes fertilizantes - fosfato bicálcico (FB), biossólido (BS) e fezes de codorna (FC) na produção de plâncton. Foram utilizados 24 tanques de cimento amianto com volume útil de 100 L cada, distribuídos em delineamento inteiramente casualizado, com quatro tratamentos (os três fertilizantes e um tratamento controle, sem adubação - SA) e seis repetições. Como variáveis de controle foram avaliados a produção de Daphnia sp. e os seguintes parâmetros de qualidade da água: clorofila-a, condutividade elétrica, pH, oxigênio dissolvido, temperatura, nitrogênio amoniacal e orgânico, fósforo total e dureza total. O peso da biomassa de Daphnia sp. foi medido ao final do experimento (13º dia). Os parâmetros de controle de qualidade da água foram aferidos em três momentos ao longo do período experimental: primeiro, oitavo e décimo terceiro dias. O peso máximo da biomassa de Daphnia sp. foi encontrado nos tanques adubados com FC (36,0 g), seguido do BS (16,8 g), SA (6,8 g) e FB (5,2 g). Observou-se correspondência entre os valores de clorofila-a e o peso da biomassa de Daphnia sp., o que, muito provavelmente, reflete interações entre as comunidades fito e zooplanctônicas. No segundo experimento, realizado no período de fevereiro e março de 2008, procurou-se avaliar a aplicação de diferentes níveis de biossólidos na produção de plâncton. Foram utilizados 25 tanques, distribuídos em delineamento inteiramente casualizado com cinco tratamentos (quatro níveis de biossólidos - 25 g, 50 g, 75 g e 100 g e um tratamento controle, sem adubação) e cinco repetições. As variáveis de controle e o plano de amostragem foram os mesmos do primeiro experimento. Os pesos médios de biomassa de Daphnia sp. encontrados nos tanques foram: 16,51 g com 100 g de biossólidos; 14,63 g com 75 g de biossólidos; 14,10 g com 50 g de biossólidos; 12,85 g com 25 g de biossólidos; 5,80 g no tanque sem adubação. A aplicação de quantidades crescentes de biossólidos não comprometeu qualidade da água a ponto de torná-la inadequada ao cultivo de organismos aquáticos. Entretanto, a despeito da produção crescente de fitoplâncton de acordo com níveis crescentes de biossólidos, a produção de Daphnia sp. tendeu a estabilizar-se a partir da aplicação de 50 g de biossólidos. O terceiro experimento, realizado de março a abril de 2008 com duração de quatorze dias, envolveu a utilização de biossólidos com diferentes ajustes de NPK. Foram utilizados os mesmos 25 tanques de cimento amianto e delineamentos anteriores, com cinco tratamentos (cinco níveis de NPK em 50 g de biossólidos) e cinco repetições. As variáveis de controle e o plano de amostragem foram essencialmente os mesmos dos experimentos anteriores, porém medindo-se e nitrato e fósforo solúvel em lugar de nitrogênio orgânico e fósforo total. A aplicação de biossólidos com diferentes formulações de NPK não comprometeu a qualidade da água a ponto de torná-la inadequada ao cultivo de organismos aquáticos. Entretanto, a despeito da produção crescente de fitoplâncton de acordo com níveis crescentes de fósforo na formulação dos fertilizantes, os pesos médios de biomassa de Daphnia sp. encontrados nos tanques, em torno de 10 g, não diferiram estatisticamente para os diversos tratamentos. Os resultados sugerem que biossólidos podem ser utilizados com sucesso como fertilizante de águas para produção de fitoplâncton e de zooplâncton.
46

Effects of Biosolids Application and Harvest Frequency on Switchgrass Yield, Feedstock Quality, and Theoretical Ethanol Yield

Liu, Xiaojun 04 February 2013 (has links)
Switchgrass (Panicum virgatum L.) is a promising bioenergy crop for biofuel production. However, the effects of biosolids application on biomass yield, nitrogen (N) concentration, feedstock quality and theoretical ethanol yield (TEY) are rarely reported in the literature. The objectives of this research were: 1) to compare the effects of biosolids application on biomass yield, N concentration, feedstock quality and TEY, and 2) to compare the effects of harvest frequency on biomass yield, N concentration, feedstock quality and TEY. This experiment began in 2010 and tested four plant available N (PAN) rates of biosolids (0, 153, 306, 459 kg ha-1), one urea rate (180 kg ha-1), and two harvest frequencies (cut once in November or cut in July and November) on a Davidson soil at Orange, VA. Biosolids and urea applications increased biomass yield and TEY across years relative to control, but had no effects on measures of feedstock quality. Inconsistent biomass yield responses to harvest frequency were observed during three years. Cutting once per year consistently increased biomass lignin, cellulose, and hemicellulose concentrations, theoretical ethanol potential (TEP), and reduced N and ash concentrations compared to two cuts. Across years one cut increased TEY by 11% over the two cuts. The results demonstrate that biosolids can be applied as an N source to increase biomass yield and TEY. Two cuts increased biomass yield but reduced TEP, and had inconsistent effects on TEY. / Master of Science
47

Variation Of Geotechnical Strength Properties With Age Of Landfills Accepting Biosolids

Pinapati, Kishore 01 January 2006 (has links)
The solid portion of waste disposal, known as Municipal Solid Waste (MSW) can be landfilled. Landfilling has proved to be a safe, sanitary and economical method of disposal. A by-product from wastewater treatment plants called biosolids is sometimes co-disposed along with MSW in landfills. Recent work at the University of Central Florida has focused on the behavior of the mixture of MSW and biosolids. As an increased amount of waste accumulates in these landfills, it creates a new problem – the geotechnical stability of landfills. In current literature, classical geotechnical testing methods have been followed to find the strength properties of these landfill materials. Furthermore, geotechnical methods of slope stability analyses have been employed to determine the stability of landfill slopes. As these materials have a high organic content, their strength properties may potentially change with time because of the decay of the organic materials. In the present work, an attempt is made to monitor the change in the geotechnical strength properties of the landfill materials as a function of time. Direct shear tests used for soil testing, with some modifications, were performed on cured compost samples of MSW mixed with biosolids. Geotechnical strength properties of these cured samples were compared to those of an artificially prepared mixture of MSW and biosolids, from the published literature. In addition, direct shear tests are also performed to find the interface properties of a geonet with the cured samples to check the role of a geonet in reinforcing the landfill slopes. A slope stability analysis software SLOPE/W is used to analyze the stability of the landfills. Cohesion is observed to decrease with time while the friction angle increases with time. Stability (the factor of safety against failure) of landfill slopes increases with time due to increased effective stresses and increased friction angle, as the organic material decays. This may result in additional subsidence but an increase in the effective shear strength with time. Based on the interface test results and subsequent slope stability analyses, it is found that the inclusion of a geonet improves the slope stability of a landfill. This could be a potential benefit to the landfill as reinforcement if properly placed. Based on the slope stability analysis on landfills with different slopes, it is concluded that the slope stability of a landfill is improved by keeping the slopes less steep.
48

Assessment of the Basis for Increased Illness in Workers Exposed to Biosolids

Niang, Mamadou 22 October 2020 (has links)
No description available.
49

Bioaerosols Generated from Biosolids Applied Farm Fields in Wood County, Ohio

Ghosh, Jaydeep 09 November 2005 (has links)
No description available.
50

Vertical Profile of Heavy Metal Concentrations in Soil From an Agricultural Field With and Without Applied Sewage Sludge in Bowling Green, Wood County, Ohio

Tanner, Christopher R. 26 June 2006 (has links)
No description available.

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