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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.
121

Produção de madeira, ciclagem de nutrientes e fertilidade do solo em plantios de Eucalyptus grandis, após aplicação de lodo de esgoto / Wood production, nutrient cycling and soil fertility in Eucalyptus grandis stand after sewage sludge application

Paulo Henrique Müller da Silva 19 January 2007 (has links)
Poucos municípios brasileiros têm estações de tratamento de esgoto (ETEs), sendo que uma grande parte do esgoto ainda não é tratada, causando forte impacto ambiental devido ao seu despejo ?in natura? nos cursos de água. O processo de tratamento de esgoto gera grande quantidade de lodo cujo destino final deve ser bem planejado, pois acarreta além de conseqüências ambientais, conseqüências de caráter econômico, social e sanitário. Um destino ecologicamente desejável seria a utilização desse resíduo, depois de tratado (biossólido), em plantios florestais como fertilizante e condicionador de solo. Mas, ainda são poucos os conhecimentos disponíveis para que a sua utilização seja realizada em larga escala. Recentemente, o Conselho Nacional do Meio Ambiente (CONAMA), através de resolução específica estabeleceu critérios e procedimentos para o uso de lodo de esgoto em áreas agrícolas, visando benefícios à agricultura e evitando riscos à saúde pública e ao ambiente. Conseqüentemente, amplia-se agora a necessidade de estudos mais aprofundados sobre o assunto. Esta pesquisa teve como objetivo aprofundar os conhecimentos sobre a influência da utilização de lodo de esgoto nas plantações florestais. Em abril de 2003, foi implantado um experimento na Estação Experimental de Ciências Florestais da ESALQ/USP em Itatinga com a finalidade de estudar o crescimento das árvores de Eucalyptus grandis tratadas com doses crescentes dos lodos úmido (torta) e seco (granulado) e, principalmente, a ciclagem de nutrientes no ecossistema, através de observações relacionadas com os processos de produção, acúmulo e decomposição da serapilheira nas parcelas experimentais dos diferentes tratamentos. Supõe-se que a aplicação dos lodos de esgoto úmido e seco nas linhas de plantio dos eucaliptos altere de maneira positiva a fertilidade do solo, incrementando significativamente o volume de madeira produzida pelos eucaliptos, servindo como fontes de nutrientes, portanto, o uso do lodo permitiria a substituição das adubações nitrogenada e fosfatada, usualmente aplicadas nos plantios florestais, e poderia suprir também a necessidade da aplicação de micronutrientes (exceto o boro). Também a aplicação dos lodos úmido e seco deve refletir de maneira positiva na ciclagem de nutrientes, alterando a quantidade e a velocidade da transferência dos diferentes elementos entre os compartimentos do sistema Árvores - Serapilheira - Solo. / Several Brazilian cities have sewer treatment stations, but a lot of cities do not treat the sewage yet, causing a strong environmental impact, mainly in water courses. The sewer treatment process generates a big amount of sewage sludge, so the final destination must be well studied, because it involves environmental, economic, social and sanitary consequences. A good destination of this residue would be its application, after treated (biosolids), in forest stands for fertilizing and conditioning of soil. Recently, CONAMA (National Advice of the Environment) established procedures and criteria for the use in agricultural areas of sewage sludge for benefits to agriculture and preventing risks to the health and the environment. Consequently, more scientific information will be necessary for sewage sludge application on a large scale. The aim of this study was to extend the knowledge about the influence of sewage sludge (humid and dry) on eucalypts plantations. So in April 2003, an experimental stand of Eucalyptus grandis was planted in the Experimental Station of Itatinga (ESALQ/USP). The purpose was to study the growth of the eucalypts, treated with increasing doses of humid and dry sewage sludge, and also the nutrients cycling in the forest plantation ecosystem through the production, accumulation and decomposition of the leaf-litter in the different treatments. It is expected that application of humid and dry sewage sludge in the rows of planting may modify positively soil fertility, wood volume produced by eucalypts, and nutrient cycling in the ecosystem.
122

Bioaccessibility based in-situ remediation of lead-contaminated soils using local materials

Vazquez Miranda, Martina Laura January 2021 (has links)
No description available.
123

INTERNSHIP REPORT Butler County Department of Environmental Services

Sackenheim, Adam Michael 06 August 2004 (has links)
No description available.
124

Evaluation of IMET<sup>TM</sup> Technology for Enhancement of Wastewater Sludge Digestion

Dissanayake, Mevan C. 24 June 2014 (has links)
No description available.
125

The Relationships of Pathogenic Microbes, Chemical Parameters, and Biogas Production During Anaerobic Digestion of Manure-based Biosolids

Rosenblum, James S. January 2013 (has links)
No description available.
126

Organic By-Product Materials as Soil Amendments

Tvergyak, Jennifer Louise 19 July 2012 (has links)
No description available.
127

Performance of Acid-Gas Anaerobic Digestion for Minimization of Siloxane and Hydrogen Sulfide Produced in Biogas for Energy Recovery

Bowles, Evan Christopher 11 April 2012 (has links)
Organosilicon compounds, which are heavily utilized in personal care products, are typically present, sometimes in high concentrations in the influent of wastewater treatment facilities. During anaerobic sludge digestion, these compounds volatilize and enter the methane gas recovery stream. As the methane is combusted for energy cogeneration, these compounds become oxidized to microcrystalline silicon dioxide and cause damage and potential failure of expensive infrastructure. Adsorption and other catchment methods are typically utilized for removal of these volatilized compounds in order to mitigate their entrance into methane combustion systems. This research investigated the effect of phased anaerobic digestion, specifically acid-gas digestion, on the behavior of the volatilization of these organosilicon compounds, particularly octamethylcyclotetrasiloxane (D4) and decamethylcyclopentasiloxane (D5) as these are the most abundant volatile silicone compounds present in sludge. A bench scale acid reactor anaerobic digester was operated at varying solids retention times and temperatures in order to quantify biogas effects generated in the downstream gas reactor, which was operated at a constant mesophilic conditions. Results of the research indicated that the addition of an acid reactor did not cause a change in behavior of the D4 and D5 siloxane volatilization in the downstream gas reactor. However, it was observed that hydrogen sulfide gas was decreased in the gas reactor when an acid reactor was utilized, which could permit decreased corrosivity of biogas recovery. Cumulative volatile solids reduction and gas reactor methane yield data did not indicate an enhancement due to utilization of acid-gas digestion. / Master of Science
128

Fate of Antibiotic Resistance Genes During Anaerobic Digestion of Wastewater Solids

Miller, Jennifer Hafer 28 May 2014 (has links)
Bacterial resistance to antibiotics has become a worldwide health problem, resulting in untreatable infections and escalating healthcare costs. Wastewater treatment plants are a critical point of control between anthropogenic sources of pathogens, antibiotic resistant bacteria (ARBs), antibiotic resistance genes (ARGs), and the environment through discharge of treated effluent and land application of biosolids. Recent studies observing an apparent resuscitation of pathogens and pathogen indicators and the widening realization of the importance of addressing environmental reservoirs of ARGs all lead toward the need for improved understanding of ARG fate and pathogen inactivation kinetics and mechanisms in sludge stabilization technologies. This research has investigated the fate of two pathogens, methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli, and various ARGs under pasteurization, anaerobic digestion, biosolids storage, and land application conditions. Pathogen die-off occurs at a rate specific to each pathogen and matrix in ambient and mesophilic temperature environments. Viable but nonculturable (VBNC) states are initiated by thermal treatments, such as thermophilic digestion and possibly pasteurization, and allow the persistence of pathogen cells and any ARGs contained therein through treatment and into the receiving environment where resuscitation or transformation could occur. Raw sludge ARG content does affect digester effluent quality, although the predominant mechanisms of ARG persistence may be different in mesophilic versus thermophilic digestion. In both thermophilic and mesophilic digestion, a correlation was observed between raw sludge and digester ARGs associated with Class 1 integrons, possibly as a result of horizontal gene transfer. ARB survival was shown to contribute to ARG content in mesophilic digestion, but not thermophilic digestion. Thermophilic digestion may achieve a higher ARG reduction because of reduced microbial diversity compared to mesophilic digestion. However, it is evident that horizontal gene transfer still does occur, particularly with highly mobile integrons, so that complete reduction of all ARGs would not be possible with thermophilic digestion alone. Surprisingly, the experiments that introduced various concentrations of antibiotic sulfamethoxazole and antimicrobial nanosilver did not induce enhanced rates of horizontal gene transfer. Finally, ARG concentrations in biosolids increased during cold temperature storage suggesting that there is a stress induction of horizontal gene transfer of integron-associated ARGs. / Ph. D.
129

Fração orgânica de biossólidos e efeito no estoque de carbono e qualidade da matéria orgânica de um Latossolo cultivado com eucalipto. / Organic fraction of the biosolids and effect on carbon stocks and organic matter quality in an oxisol planted with eucalyptus.

Andrade, Cristiano Alberto de 25 May 2004 (has links)
O presente trabalho teve como objetivo caracterizar o processo de decomposição da fração orgânica de biossólidos, após aplicação no solo, correlacionando com a composição química inicial da matéria orgânica (MO) dos resíduos. Também foi objetivo, quantificar, no campo, o efeito de um biossólido alcalino na MO de um Latossolo cultivado com eucalipto, após cinco anos da aplicação de doses do resíduo ou de fertilizantes minerais. A degradação da MO de biossólidos foi avaliada por meio da incubação de misturas de solo e cinco biossólidos, em dose correspondente a 40 t ha-1, com quantificação do CO2 emitido durante um período de 70 dias. Os biossólidos foram escolhidos em função de diferenças no sistema de tratamento de esgotos e/ou condicionamento químico para desidratação e/ou etapa complementar visando melhor adequação ao uso agrícola: BAC - biossólido anaeróbio condicionado com cal e cloreto férrico e desidratado mecanicamente; BAP - biossólido anaeróbio condicionado com polímero sintético e desidratado mecanicamente; BAS - biossólido anaeróbio seco termicamente; BLP = biossólido proveniente de lagoas de estabilização, condicionado com polímero sintético e desidratado mecanicamente; e CL - composto de lodo de esgoto obtido por compostagem em pilhas aeradas após mistura do BLP com bagaço de cana-de-açúcar e restos de poda urbana. A MO dos biossólidos foi analisada quanto aos teores totais, orgânicos e inorgânicos de C, N e P; teor de carbono solúvel em água; frações do carbono orgânico em função de graus de oxidação; e teores de açúcares solúveis, proteína bruta, lipídeos, hemicelulose, celulose, lignina, taninos e fenóis. Em todos os biossólidos o C e o N predominaram em compostos orgânicos, enquanto que a partição do P, entre compostos orgânicos e inorgânicos, foi função do tratamento dos esgotos e/ou condicionamento para desidratação. As taxas de degradação dos biossólidos foram, de modo geral, baixas e os menores valores foram observados para o BLP e o CL, provavelmente devido a maior estabilidade da MO desses resíduos. Em todos os biossólidos houve expressiva participação do compartimento protéico como constituinte da MO, apresentando valores médios entre 25 e 46 % do total de MO. A proteína bruta foi o parâmetro que melhor correlacionou com a taxa de degradação dos biossólidos ao final de 70 dias de incubação (r = 0,999 e Prob. > t inferior a 10-4), sendo promissora sua utilização no sentido de previsão da degradação da MO de biossólidos após aplicação no solo. O estudo de caso, no campo, foi desenvolvido em área com Eucalyptus grandis plantado em março de 1998 e fertilizado, quatro meses depois, com biossólido ou fertilizantes minerais. Os tratamentos avaliados foram: (i) Controle; (ii) Fertilização Mineral com N, P, K, B e Zn (Fert. Mineral) ; (iii) 10 t ha-1 de biossólido + K (10 t há-1); (iv) 20 t ha-1 de biossólido + K (20 t ha-1); e (v) 40 t ha-1 de biossólido + K (40 t ha-1). Em setembro de 2003 foram coletadas amostras de solo das camadas 0-5, 5-10, 10-20, 20-30 e 30-60 cm. Em todas as amostras foram determinados os teores totais de C e N e a densidade aparente. Nas amostras coletadas até 20 cm de profundidade, foram feitas determinações de pH, frações de C-orgânico por graus de oxidação, teores de alguns compostos orgânicos (açúcares solúveis, proteína bruta, lipídeos, hemicelulose, celulose e lignina), CTC a pH 7,0 e CTC ao pH natural. Os resultados praticamente não evidenciaram alterações na MO do solo, após cinco anos da aplicação do biossólido ou de fertilizantes minerais. Os estoques médios de C e N, até 60 cm de profundidade, foram iguais a 92,86 e 4,41 t ha-1, respectivamente. Cerca de 50 % do total de C esteve no compartimento denominado lábil, o que é típico de sistemas naturais ou manejados onde há o favorecimento ao retorno de resíduos vegetais ao solo. Dos compostos orgânicos determinados, houve variação significativa somente do teor de lignina na MO do solo (0-5 cm), com maiores valores nos tratamentos 40 t ha-1 de biossólido e Fert. Mineral, sendo tais resultados atribuídos a maior deposição de folhas nesses tratamentos e à natureza recalcitrante da lignina no ambiente. A CTC (pH natural) mostrou-se mais dependente dos valores pH do solo, do que dos teores de C, não evidenciando benefícios da MO dos biossólidos nessa propriedade, somente de forma indireta pela elevação do pH do solo tratado. / The aim of this work was to characterize the organic fraction decomposition process of the biosolids in soil, correlating to initial organic matter (OM) composition of residue. Another objective was quantify, under field conditions, the effect of alkaline biosolid on Oxisol OM, in a site planted with eucalyptus and after five years of the residue application or mineral fertilizers application. The OM decomposition of the biosolids was evaluated using the incubation of soil mixtures and five biosolids, in a rate of 40 t ha-1, with quantification of the CO2 emitted during a period of 70 days. The biosolids were chosen in function of the treatment system of sewage and/or chemical conditioning for biosolid dehydration and/or complementary stage to adequate the residue for agricultural use: BAC - anaerobic biosolid conditioned with lime and ferric chloride and mechanically dehydrated; BAP - anaerobic biosolid conditioned with synthetic polymers mechanically dehydrated; BLP - biosolid originated in stabilization ponds and conditioned with synthetic polymers mechanically dehydrated; CL - sewage sludge compost originated from aerated pile composting of a mixture of BLP, crushed sugar cane and remains of urban pruning. The OM of the biosolids was analyzed regarding the total, organic and inorganic contents of C, N and P; content of water-soluble carbon; oxidizible organic carbon fractions; and contents of soluble sugars, crude protein, lipids, hemicellulose, cellulose, lignin, tannins and phenols. All biosolids had C and N predominance in organic compounds, while the P distribution in organic and inorganic compounds was as a function of the treatment used in the Plants. The decomposition rates of the biosolids, in general, were low and the lowest values were observed for BLP and CL, probably due to higher OM stability of the residues. There was expressive participation of protein pool in all biosolids, with mean values between 25 and 46 % of total OM. The crude protein was the parameter that better correlated with biosolid degradation rate at the end of 70 days of incubation (r = 0.999 e Prob. > t lower than 10-4), being promising its use in order to expect the biosolid OM decomposition after soil application. The study case, on the field, was developed in an area with Eucalyptus grandis planted on March 1998 and fertilized, after four months, with biosolid or mineral fertilizers. The appraised treatments were: (i) Control; (ii) Mineral Fertilization with N, P, K, B and Zn (Mineral Fert.); (iii) 10 t ha-1 of biosolid + K (10 t ha-1); (iv) 20 t ha-1 of biosolid + K (20 t ha-1); and (v) 40 t ha-1 of biosolid + K (40 t ha-1). Soil samples were taken from 0-5, 5-10, 10-20, 20-30 and 30-60 cm soil depths, on September 2003. Total amounts of C and N and bulk density were determined in all samples. In the samples collected up to 20 cm of depth, were made pH determinations, oxidizible organic carbon fractions, amounts of some organic compounds (soluble sugars, crude protein, lipids, hemicellulose, cellulose and lignin), CEC the pH 7,0 and CEC to the natural pH. In general, the results did not show differences in the soil OM, after five years of the biosolid application or mineral fertilizers application. The mean values of C and N stocks up to 60 cm soil depth were the same to 92.86 and 4.41 t ha-1, respectively. About 50% of the total C was in the fraction denominated labile, which is typical of natural systems or managed systems where the return of plant residues to the soil is allowed. From the determined organic compounds, only the lignin content (0-5 cm depth) was different between the treatments, with higher concentrations in the treatments 40 t ha-1 of biosolid and Mineral Fert., probably because the largest depositions of leaves on soil surface in these treatments and the natural slow decay of lignin. The CEC (natural pH) values were more dependent on soil pH, than on the soil C content. Benefits of OM biosolids in soil CEC were not observed.
130

Valorisation de biodéchets pour la restauration de sites dégradés de Nouvelle-Calédonie / Biowaste valorization for restoration of New Caledonian degraded sites

Velayoudon, Prescilia 20 February 2015 (has links)
Les biodéchets tels que les boues de stations d’épuration ou les fientes de poules peuvent être utilisés pour l’amendement organique des sols. En Nouvelle-Calédonie, l’accroissement démographique a pour conséquence une augmentation de la production de ces déchets. Aussi, la gestion et le devenir de ces derniers est une problématique majeure pour les collectivités. D’autre part, il existe de nombreux sites dégradés liés à l’activité minière. Il s’agit notamment des sites miniers après exploitation, caractérisés par un substrat ultramafique, auxquels s’ajoutent les zones industrielles.L’objectif de cette thèse cherche à apporter des données sur la valorisation des biodéchets (boues d’épuration et fientes de poules) pour la restauration de sites dégradés. Trois types de site sont sélectionnés : un ferralsol non remanié, un ferralsol remanié par l’activité minière et un site industriel. A partir de ces études indépendantes, nous tenterons de répondre à l’opportunité de revégétaliser un site à partir du stock de graine du sol d’origine ou de végétalisé un site dépourvu de son sol d’origine par plantations. Sur ces 3 sites, il a été suivi les variables biométriques, chimiques des végétaux et les variables chimiques et physico-chimiques des substrats.Les résultats sont, dans l’ensemble, encourageants avec des effets très positifs sur la croissance végétale. La quantité de boue à apporter sera à moduler en fonction des objectifs à obtenir entre production végétale et diversité spécifique. La faible biodisponibilité des ETM du sol semble être favorable à l’épandage de biodéchets sur ces substrats spécifiques pour la réhabilitation des sites dégradés. / Biowaste like biosolids or poultry can be used for organic amendment of soils. In New Caledonia, the demographic development involves an increase in waste production and the management of these ones is highly important for local authorities. On the other hand, there are numerous degraded sites issued from mining activity. In particular mining sites after exploitation, characterized by an ultramafic substratum, and industrial sites The objective of this thesis consists to bring data on biowaste valorization (sewage sludge and poultry) for degraded sites restoration. Three kind of degraded sites are selected: a not-reorganized ferralsol, a ferralsol reorganized by the mining activity and an industrial site. From these independent studies, we try to evaluate the opportunity of revegetalization from the seed bank of the original soil, or vegetalized a site free of original soil by plantations. On these 3 sites, it was followed the biometric, chemical variables of the vegetal species and chemical and physico-chemical variables of the substrata. The results are encouraging, with positive effects on plant growth. The biosolids quantity should be modulating according to the objectives to obtain between plant production and specific diversity. The low bioavailability of the ETM seems to be favorable to the biowaste manuring of these specific substrata for the rehabilitation of the degraded sites.

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