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Avaliação da genotoxicidade e mutagenicidade de misturas comerciais de diesel e biodiesel puras e em simulações de vazamento em água e soloLeme, Daniela Morais [UNESP] 20 December 2010 (has links) (PDF)
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000638858.pdf: 2789008 bytes, checksum: 13a14092763ec9a00dd9bfbff49af27a (MD5) / A questão energética é hoje um tema de preocupação mundial. A limitação das fontes de energia fóssil e seus efeitos indesejáveis ao meio ambiente têm estimulado a busca de novas fontes alternativas, desde que renováveis. Em diversos países, como no Brasil, têm sido destinados grandes incentivos ao desenvolvimento do setor de biocombustíveis, no qual se inclui o biodiesel. O futuro promissor do biodiesel está relacionado não apenas ao fato de ser um combustível renovável, mas também às suas contribuições na redução da emissão de poluentes atmosféricos e à sua maior degradabilidade, em relação aos combustíveis fósseis. No entanto, poucos são os estudos realizados com o biodiesel para avaliar os seus possíveis impactos, quando usados puro ou em misturas ao óleo diesel, sobre o ambiente (principalmente corpos d’águas e solos) e sobre os organismos vivos, em caso de uma possível contaminação ambiental. O presente estudo teve como objetivo avaliar a citotoxicidade, genotoxicidade e mutagenicidade do biodiesel e de suas misturas com diesel (B5, B20 e B50), por meio de simulações de vazamento em água e solo. As simulações foram realizadas no verão, para caracterizar um vazamento em condições tropicais, sendo aplicados diferentes ensaios biológicos [teste de Allium cepa, ensaio Salmonella/microssoma, ensaios de mutagenicidade com células CHO-K1 e HepG2 in vitro, ensaio para detecção de indução de morte celular (alterações do ΔΨm, externalização da fosfatidilserina), avaliação da citotoxicidade em tempo real (sistema xCELLigence™)] nas amostras de água e solo obtidas nos experimentos. Foi observada no presente estudo uma significativa citotoxicidade, que foi relacionada com constituintes do óleo diesel, mais especificamente, com os hidrocarbonetos policíclicos aromáticos (PAHs). Já os efeitos genotóxicos/mutagênicos, observados... / The energy-related issue is currently a subject that causes world concern. The limitations of fossil energy sources and their undesirable effects upon the environment have encouraged the search for new alternative sources, as long as they are renewable ones. In several countries, like Brazil, great incentives have been allocated to the development of the biofuel sector, and that includes biodiesel. The promising future of biodiesel is related not only the fact of being a renewable biofuel, but also to its contribution to reducing release of air pollutants and its higher degradability when compared to fossil fuels. Nevertheless, not enough studies have been conducted with biodiesel to evaluate their possible impacts – either when they are used crude or in biodiesel blends – upon both the environment (especially water bodies and soils) and living organisms, should there be environmental contamination. The aim of this study was to assess toxicity, genotoxicity and mutagenicity of biodiesel and its diesel blends (B5, B20 and B50), by simulating spills into water and soil. The simulations were carried out in the summer in order to characterize a spill under tropical conditions, and different assays [Allium cepa test, Salmonella mutagenicity assay, in vitro mutagenicity assays with CHO-K1 and HepG2 cells line, detection of cell death inductions (changes in ΔΨm, phosphatidylserine externalization), cytotoxicity assessment by xCELLigence™ system] were conducted using soil and water samples obtained in the experiment. In this study, significant citotoxicity was observed, which was found to be related to biodiesel contaminants, even more specifically, to its polycyclic aromatic hydrocarbons (PAHs). On the other hand, the genotoxic/mutagenic effects observed in the other assays done with diesel and biodiesel proved to result from the action of pollutants present in the raw material used... (Complete abstract click electronic access below)
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Metabolismo e qualidade da bebida em cafeeiro expostos ao cádmio, níquel e zinco / Metabolism and beverage quality of coffee plants exposed to cadmium, nickel and zincTiago Tezotto 02 February 2011 (has links)
A contaminação ambiental por metais pesados, entre os quais o cádmio (Cd), níquel (Ni) e zinco (Zn), tanto nos solos cultivados quanto nos produtos agrícolas, demanda constante monitoramento do solo, bem como a quantificação desses elementos nos diferentes órgãos dos vegetais. No manejo da adubação e outras práticas culturais, há contaminação indesejável de metais pesados que se acumulam nos solos ao longo dos anos, podendo causar danos ao crescimento vegetal, produção e/ou qualidade do produto agrícola. Considerando a relevância da problemática dos metais pesados nos sistemas agrícolas, é essencial o conhecimento da ação do Cd, Ni e Zn nos processos metabólicos no cafeeiro. A proposta desta pesquisa foi verificar a influência das aplicações de doses crescentes de Cd, Ni e Zn sobre as características nutricionais, fisiológicas e bioquímicas em plantas de cafeeiro em produção e na qualidade da bebida. Por meio dos parâmetros analisados até 128 dias, a ordem crescente de toxidez é de Ni, Zn e Cd. A distribuição de Cd é maior nos ramos, grãos e folha; Ni nas folhas, ramos e grãos e Zn nos ramos, folhas e grãos. O estado nutricional do cafeeiro não é afetado pela aplicação dos metais, com exceção do nitrogênio e do fósforo, que reduz nas maiores doses de Cd e Zn. A produtividade e qualidade da bebida são reduzidas em razão da aplicação dos metais. / Environmental contamination by heavy metals, including Cd, Ni and Zn, in both cultivated soils and agricultural products, takes constant monitoring of soils and the quantification of these elements in different plant parts. The management of fertilizer and other cultural practices, there are undesirable contamination of heavy metals that accumulate in soils over the years, causing damage to plant growth, production and/or quality of products. Considering the growing concern with heavy metals in agricultural systems is essential research focused on the physiological mechanism of Cd, Ni and Zn in coffee plants. Therefore, to evaluate the translocation of metals to coffee beans, the monitoring and the quantification of these elements in soils and different organs of coffee plants are required. The aim of this study was to evaluate the influence of applications times and rates of Cd, Ni and Zn on the nutritional, physiological and biochemical changes in coffee plants as well as cup quality drink under field condition. According to the results evaluated up to 128 days exposure to metals, the order of increasing toxicity was Ni>Zn>Cd. The distribution of Cd was higher in the plagiotropic branches>grain>leaf; Ni in leaves>stems>grains, and Zn in stems>leaves>grains, respectively. The nutritional status of coffee plants was not affected by the application of metals, except nitrogen and phosphorus, which reduced the highest levels of Cd and Zn. The coffee yield and cup quality drink decreased due to metals exposition.
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Bário (Ba), cádmio (Cd), cromo (Cr), cobre (Cu), níquel (Ni), chumbo (Pb), selênio (Se) e zinco (Zn) no ambiente canavieiro adubado com composto de lodo de esgoto / Barium, cadmium, chromium, copper, nickel, lead, selenium and zinc in the sugarcane environment fertilized with compost of sewage sludgeJosé Carlos Pöppl Neto 27 September 2013 (has links)
Para o uso agrícola de composto de lodo de esgoto, há escassez de informações sobre os elementos Ba, Cd, Cr, Cu, Ni, Pb, Se e Zn, que podem contaminar o ambiente. Os elementos Ba, Cd, Cr, Ni e Pb, metais pesados e o Se, um ametal, de modo geral, têm sido pouco avaliados, principalmente pelos baixos teores no solo e na planta. Dessa forma, com o presente estudo, objetivou-se avaliar os teores de Ba, Cd, Cr, Cu, Ni, Pb, Se e Zn no solo e na cultura da cana-açúcar em função da aplicação de composto de lodo de esgoto. O experimento foi conduzido em área comercial de produção de cana-de-açúcar, primeira cana soca cultivada em Argissolo Vermelho distrófico. Foram aplicadas quatro doses de composto de lodo (0; 14,7; 29,4 e 44,5 t ha-1, base seca), quatro de nitrogênio (0, 36,3 ; 72,6 e 110 kg ha-1) e duas de P2O5 (0, 30 kg ha-1), em delineamento experimental de blocos casualizados, em esquema fatorial 4x4x2, com três repetições. Foram aplicados 77 kg ha-1 de K2O em todas as parcelas para suprir a falta desse nutriente no composto. Os teores dos metais pesados foram determinados por espectrometria de massas com plasma acoplado (ICP-MS). A aplicação dos fertilizantes minerais nitrogenado e fosfatado não resultou em incremento nos teores dos metais pesados no solo e na planta. A aplicação do composto resultou em incremento de duas vezes nos teores iniciais de Zn no solo e na planta. Para Cd, Ni, Pb e Se, houve aumento nos teores do solo e da planta, em faixas que variam de 12% a 60%, em relação ao tratamento sem composto. Para o Cu, foi observado um incremento de 13% no solo, porém sem alterar o teor na planta. Os teores Ba e Cr no solo e na cana-de-açúcar não foram alterados pela aplicação do composto de lodo de esgoto. Para todos os elementos, os teores observados estiveram dentro da faixa considerada normal para solo e planta. A aplicação de composto de lodo de esgoto, dentro dos critérios técnicos e no modelo de condução do experimento de um ano de cultivo, não resulta em contaminação do ambiente canavieiro pelos elementos avaliados / For agricultural use of sewage sludge compost, there is few information on the elements Ba, Cd, Cr, Cu, Ni, Pb, Se and Zn, that can contaminate the environment. The elements Ba, Cd, Cr, Ni and Pb, heavy metals, and the Se, one nonmetal, generally have been little evaluated especially by low levels in soil and plant. The present study objected to evaluate the effects of application of sewage sludge compost on the content of Ba, Cd, Cr, Cu, Ni, Pb, Se and Zn in soil and the sugar cane. The experiment was conducted in a commercial area of production of sugarcane, first ratoon cane, cultivated in a Rhodic Paleudalf. There were applied four doses of sludge compost (0, 14.7, 29.4 and 44.5 t ha-1, dry basis), four of N rates (0, 36.3, 72.6 and 110 kg ha-1) and two of P2O5 (0 and 30 kg ha-1), in a randomized block design in a factorial scheme 4x4x2 with three replications. Were applied 77 kg ha-1 of K2O in all plots to supply the lack of this nutrient in the compost. The concentration of heavy metals were determined by inductively coupled plasma mass spectrometry (ICP-MS). The rates of nitrogen and phosphate fertilizers did not result in increase in concentration of heavy metals in soil and plant. The compost application rates resulted in an increase of twice the initial concentration of Zn in soil and plant. The concentration of Cd, Ni, Pb and Se increased in soil and plant, ranging from 12% to 60%, compared to treatment without compound. For Cu, there was a 13% increase in the soil, without changing in the plant. The concentration of Ba and Cr in soil and sugarcane were not altered by the application of compost of sewage sludge. For all elements, the levels found were within the range considered normal for soil and plant. The application of sewage sludge compost, following the technical criteria and the model of conducting the experiment of one year of cultivation, does not result in contamination in the sugarcane environment by the elements evaluated
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Caracterização físico-química de solos de mangue e avaliação de sua contaminação por esgoto doméstico via traçadores fecais. / Physicochemical characterization of mangrove soils and evaluation of contamination by domestic sewage by faecal tracers.Lilian Pittol Firme 29 September 2003 (has links)
Os manguezais são ecossistemas que portam comunidades vegetais típicas de ambientes alagados, resistentes à alta salinidade da água e do solo. Não são muito ricos em espécies, porém, destacam-se pela grande importância ecológica que desempenham. Por isso podem ser considerados um dos mais produtivos ambientes naturais do Brasil. Os solos do subsistema estuarino do manguezal são pouco conhecidos e a ênfase em sua descrição e estudo neste trabalho surgiu do fato de que no Estado de São Paulo inúmeras áreas de mangue vêm sendo alvo de constante pressões sócio-econômicas. No município do Guarujá, assim como em grande parte da Baixada Santista os solos de mangue vêm sofrendo crescente degradação devido à ocupação urbana de alta intensidade e saneamento básico precário. Este trabalho teve como objetivo estudar as características mineralógicas e fisico-químicas em uma transeção de solos de mangue do rio Crumahú, no município do Guarujá, junto ao bairro Morrinhos, e determinar a distribuição horizontal e vertical de poluentes em função da descarga de efluentes urbanos. Os perfis foram amostrados, utilizando amostrador para solos inundados, em 3 profundidades numa transeção de 160m, que vai da margem do canal do rio Crumahú até a restinga, e com pontos de coleta a cada 10 m. No laboratório, foram realizadas análises físicas, químicas e mineralógicas. A mineralogia das frações areia, silte e argila foi estudada por meio de difratogramas de raio-X. Para a distribuição de poluentes gerados em função da descarga pontual de esgoto doméstico foram utilizados traçadores fecais fazendo uso da relação coprostanol/colesterol entre outras, para confirmação da contaminação. Análises com os traçadores foram feitas por cromatografia gasosa. A análise granulométrica evidencia mudanças do regime de sedimentação recente. O microrrelevo do maguezal é dinâmico e isso foi evidenciado pela distribuição granulometrica. O fluxo e refluxo da maré influenciou alguns atributos do solo ao longo da transeção como a concentração de cátions e ânions solúveis e a condutividade elétrica. Com o secamento das amostras de solo, houve uma oxidação induzida o que levou à diminuição do pH, aumento de sulfato e liberação de Al trocável. Foram encontrados minerais como caulinita, mica, esmectita, ortoclásio e quartzo. Os maiores índices de contaminação foram encontrados na profundidade de 30-50 cm, enquanto que, na profundidade de 60-80 cm esta não foi detectada. A zona de contato mangue-restinga caracteriza-se como local de acúmulo de contaminantes Foi verificada a diminuição das relações de esteróis no sentido do prolongamento da transeção. Toda a área estudada está contaminada por esgoto doméstico podendo colocar em risco todo o ecossistema local. / Mangroves are ecosystems that carry typical biological communities, adapted to flooded environments, which are resistant to water and soils salinity. Although they are not very rich in species, they stand out for their great ecological importance. Hence, they can be considered one of the most productive natural environments of Brazil. Little is known about the soils in a mangrove ecosystem, and the emphasis on its study in the present work came about as a consequence of the fact that in São Paulo State many of these ecosystems are continuously suffering from antropic impacts. In Guarujá municipal district, as well as in a large part of Baixada Santista, mangrove soils are suffering from degradation due to the high-density urban occupation and precarious sanitary conditions. The objective of this work was to study the mineralogical and physicochemical characteristics of mangroves soils located on a transect in the Crumahú river, in Guarujá municipal district; and to determine the horizontal and vertical distribution of pollutant. Profiles were sampled at 3 different depths along a transect of 160m, using a sampler for flooded soils. The physical, chemical and mineralogical analyses were carried out in the Laboratory. X-ray diffractions were used for the characterization of sand, silt and clay fraction mineralogy. Faecal tracers (coprostanol/cholesterol) were used to characterize the pollutant distribution along the transect. Faecal tracer analyses were made by gaseous chromatography. The granulometric analysis showed recent changes in the sedimentation pattern. The mangrove microrelief is dynamic and this could be observed by the granulometric distribution. The tides influenced some soil attributes along the transect such as soluble cations and anions concentration and electrical conductivity. After the samples were dried, there was an induced oxidation resulting in a pH decrease, sulphate increase and exchangeable aluminum liberation. Kaolinite, mica, smectite, orthoclase and quartz were found in the samples. The largest indexes of contamination were found at the depth of 30-50cm while, at the depth of 60-80cm, no contamination was detected. The area where the mangrove meets the restinga (coastal reef) is characterized by an accumulation of pollutants. Sterols rate decreased along the transect. The whole studied area is polluted by domestic sewage what could put in risk the whole local ecosystem.
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Modelos de predição do coeficiente de sorção no solo de pesticidas não iônicos: diferentes algoritmos de logP e uma abordagem alternativa de logS.Reis, Ralpho Rinaldo dos 17 May 2013 (has links)
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Previous issue date: 2013-05-17 / Collecting data on pesticide effects on the environment and several ecosystems is a slow
and costly process. Therefore, significant research efforts have been focused on developing
mathematical models to predict physical, chemical or biological properties of environmental
interest. The soil sorption coefficient normalized to organic carbon content (Koc) is a
physicochemical key parameter used in environmental risk assessments of substances
released into the environment. Thus, several logKoc prediction models that use hydrophobic
parameter (logP) or the logarithm of water solubility (logS) as descriptor have been reported
in the last decades. Mostly, due to the lack of reliable experimental values of logP or logS,
algorithms are used to calculate such properties. Despite the availability and easiness to
access several algorithms for this purpose, scientific studies do not describe the procedure
adopted to choose the algorithm used in quantitative structure-property relationship (QSPR)
studies. Furthermore, the strong correlation between logP and logS prevents their application
in the same mathematical equation obtained by multiple linear regression method. Since the
sorption process of a chemical compound in soil is related both to its water solubility and its
water/organic matter partition, it is expected models that are able to combine these two
properties will can record more realistic results. This doctoral dissertation consists of two
scientific papers. In the first one, a study was carried out to check the influence of choosing
logP algorithm on logKoc modeling. Models were constructed to relate logKoc with logP
according to different freeware algorithms. All models were assessed based on their statistic
qualities and predictive power. The obtained results clearly showed that an arbitrary choice
of the algorithm may not result in the best prediction model. On the other hand, a good
choice can lead to obtaining simple models with statistic qualities and predictive power
comparable to more complex models. The second paper aims at proposing an alternative
approach for logKoc modeling, using simple descriptor of solubility, here referred as logarithm
of corrected solubility by octanol/water partition (logSP). Thus, models were built with this
descriptor and also with logP and logS conventional descriptors, which are isolated or
associated with other explicative variables of easy physicochemical interpretation. The
obtained models were validated and compared to other models previously published. The
results showed that the use of logSP descriptor to replace the conventional ones led to
obtaining simple models with statistic qualities and predictive power that are higher than
other more complex models already found in literature. / A coleta de dados relativos aos danos causados pelos pesticidas sobre o meio ambiente e
seus ecossistemas é lenta e onerosa. Desta maneira, grandes incentivos têm sido
destinados às pesquisas que visam à construção de modelos matemáticos para predição de
propriedades físicas, químicas ou biológicas de interesse ambiental. O coeficiente de sorção
no solo normalizado para o conteúdo de carbono orgânico (Koc) é um importante parâmetro
físico-químico utilizado nas avaliações de riscos ambientais das substâncias lançadas no
meio ambiente. Assim, vários modelos para predição de logKoc, utilizando o parâmetro
hidrofóbico (logP) ou o logaritmo da solubilidade em água (logS) como descritores, têm sido
publicados nas últimas décadas. Muitas vezes, em virtude da ausência de valores
experimentais confiáveis de logP ou logS, são usados algoritmos para o cálculo dessas
propriedades. Apesar da disponibilidade e facilidade de acesso a diversos algoritmos para
tal finalidade, os artigos científicos não descrevem o procedimento adotado para escolha do
algoritmo usado nos estudos QSPR. Além disto, a forte correlação entre logP e logS impede
que sejam usados em uma mesma equação obtida por regressão linear múltipla. Como o
processo de sorção de um composto químico no solo está relacionado tanto com sua
solubilidade em água como com sua partição água/matéria orgânica, espera-se que
modelos que sejam capazes de combinar essas duas informações possam gerar resultados
mais realistas. Este trabalho de tese é constituído de dois artigos. No primeiro artigo, foi feito
um estudo para verificar a influência da escolha do algoritmo de logP na modelagem de
logKoc. Foram construídos modelos que relacionam logKoc com logP a partir de diferentes
algoritmos livres disponíveis. Todos os modelos foram avaliados quanto às suas qualidades
estatísticas e poder de predição. Os resultados obtidos mostraram claramente que uma
escolha arbitrária deste algoritmo pode não levar ao melhor modelo de predição. Por outro
lado, uma boa escolha pode conduzir à obtenção de modelos simples com qualidades
estatísticas e poder de predição comparáveis a de modelos mais complexos. No segundo
artigo, o objetivo foi a proposição de uma abordagem alternativa para a modelagem de
logKoc, utilizando um descritor simples de solubilidade, aqui designado como logaritmo da
solubilidade corrigida pela partição octanol/água (logSP). Assim, foram construídos modelos
com tal descritor e também com os descritores convencionais logP e logS, isolados ou
associados com outras variáveis explicativas de fácil interpretação físico-química. Os
modelos obtidos foram validados e comparados com outros modelos publicados
anteriormente. Os resultados mostraram que o uso do descritor logSp em substituição aos
descritores convencionais conduziu à obtenção de modelos simples com qualidades
estatísticas e poder de predição superiores a de outros modelos mais complexos
encontrados na literatura.
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Bário (Ba), cádmio (Cd), cromo (Cr), cobre (Cu), níquel (Ni), chumbo (Pb), selênio (Se) e zinco (Zn) no ambiente canavieiro adubado com composto de lodo de esgoto / Barium, cadmium, chromium, copper, nickel, lead, selenium and zinc in the sugarcane environment fertilized with compost of sewage sludgePöppl Neto, José Carlos 27 September 2013 (has links)
Para o uso agrícola de composto de lodo de esgoto, há escassez de informações sobre os elementos Ba, Cd, Cr, Cu, Ni, Pb, Se e Zn, que podem contaminar o ambiente. Os elementos Ba, Cd, Cr, Ni e Pb, metais pesados e o Se, um ametal, de modo geral, têm sido pouco avaliados, principalmente pelos baixos teores no solo e na planta. Dessa forma, com o presente estudo, objetivou-se avaliar os teores de Ba, Cd, Cr, Cu, Ni, Pb, Se e Zn no solo e na cultura da cana-açúcar em função da aplicação de composto de lodo de esgoto. O experimento foi conduzido em área comercial de produção de cana-de-açúcar, primeira cana soca cultivada em Argissolo Vermelho distrófico. Foram aplicadas quatro doses de composto de lodo (0; 14,7; 29,4 e 44,5 t ha-1, base seca), quatro de nitrogênio (0, 36,3 ; 72,6 e 110 kg ha-1) e duas de P2O5 (0, 30 kg ha-1), em delineamento experimental de blocos casualizados, em esquema fatorial 4x4x2, com três repetições. Foram aplicados 77 kg ha-1 de K2O em todas as parcelas para suprir a falta desse nutriente no composto. Os teores dos metais pesados foram determinados por espectrometria de massas com plasma acoplado (ICP-MS). A aplicação dos fertilizantes minerais nitrogenado e fosfatado não resultou em incremento nos teores dos metais pesados no solo e na planta. A aplicação do composto resultou em incremento de duas vezes nos teores iniciais de Zn no solo e na planta. Para Cd, Ni, Pb e Se, houve aumento nos teores do solo e da planta, em faixas que variam de 12% a 60%, em relação ao tratamento sem composto. Para o Cu, foi observado um incremento de 13% no solo, porém sem alterar o teor na planta. Os teores Ba e Cr no solo e na cana-de-açúcar não foram alterados pela aplicação do composto de lodo de esgoto. Para todos os elementos, os teores observados estiveram dentro da faixa considerada normal para solo e planta. A aplicação de composto de lodo de esgoto, dentro dos critérios técnicos e no modelo de condução do experimento de um ano de cultivo, não resulta em contaminação do ambiente canavieiro pelos elementos avaliados / For agricultural use of sewage sludge compost, there is few information on the elements Ba, Cd, Cr, Cu, Ni, Pb, Se and Zn, that can contaminate the environment. The elements Ba, Cd, Cr, Ni and Pb, heavy metals, and the Se, one nonmetal, generally have been little evaluated especially by low levels in soil and plant. The present study objected to evaluate the effects of application of sewage sludge compost on the content of Ba, Cd, Cr, Cu, Ni, Pb, Se and Zn in soil and the sugar cane. The experiment was conducted in a commercial area of production of sugarcane, first ratoon cane, cultivated in a Rhodic Paleudalf. There were applied four doses of sludge compost (0, 14.7, 29.4 and 44.5 t ha-1, dry basis), four of N rates (0, 36.3, 72.6 and 110 kg ha-1) and two of P2O5 (0 and 30 kg ha-1), in a randomized block design in a factorial scheme 4x4x2 with three replications. Were applied 77 kg ha-1 of K2O in all plots to supply the lack of this nutrient in the compost. The concentration of heavy metals were determined by inductively coupled plasma mass spectrometry (ICP-MS). The rates of nitrogen and phosphate fertilizers did not result in increase in concentration of heavy metals in soil and plant. The compost application rates resulted in an increase of twice the initial concentration of Zn in soil and plant. The concentration of Cd, Ni, Pb and Se increased in soil and plant, ranging from 12% to 60%, compared to treatment without compound. For Cu, there was a 13% increase in the soil, without changing in the plant. The concentration of Ba and Cr in soil and sugarcane were not altered by the application of compost of sewage sludge. For all elements, the levels found were within the range considered normal for soil and plant. The application of sewage sludge compost, following the technical criteria and the model of conducting the experiment of one year of cultivation, does not result in contamination in the sugarcane environment by the elements evaluated
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Unsteady Multiphase Flow Modeling of In-situ Air Sparging System in a Variably Saturated Subsurface EnvironmentJang, Wonyong 18 November 2005 (has links)
In order to preserve groundwater resources from contamination by volatile organic compounds and to clean up sites contaminated with the compounds, we should understand fate and transport of contaminants in the subsurface systems and physicochemical processes involving remediation technologies. To enhance our understanding, numerical studies were performed on the following topics: (i) multiphase flow and contaminant transport in subsurface environments; (ii) biological transformations of contaminants; (iii) in-situ air sparging (IAS); and, thermal-enhanced venting (TEV). Among VOCs, trichloroethylene (TCE) is one of the most-frequently-detected chemicals in the contaminated groundwater. TCE and its daughter products (cis-1,2-dichloroethylene (cDCE) and vinyl chloride (VC)) are chosen as target contaminants.
Density-driven advection of gas phase is generated by the increase in gas density due to vaporization of high-molecular weight contaminants such as TCE in the unsaturated zone. The effect of the density-driven advection on fate and transport of TCE was investigated under several environmental conditions involving infiltration and permeability.
Biological transformations of contaminants can generate byproducts, which may become new toxic contaminants in subsurface systems. Sequential biotransformations of TCE, cDCE, and VC are considered herein. Under different reaction rates for two bioreaction kinetics, temporal and spatial concentration profiles of the contaminants were examined to evaluate the effect of biotransformations on multispecies transport.
IAS injects clean air into the subsurface below the groundwater table to remediate contaminated groundwater. The movement of gas and the groundwater as a multiphase flow in the saturated zone and the removal of TCE by IAS application were analyzed. Each fluid flow under IAS was examined in terms of saturation levels and fluid velocity profiles in a three-dimensional domain. Several scenarios for IAS systems were simulated to evaluate remedial performance of the systems.
TEV was simulated to investigate its efficiency on the removal of a nonaqueous phase liquid in the unsaturated zone under different operational conditions.
For numerical studies herein, the governing equations for multiphase flow, multispecies transport, and heat energy in porous media were developed and solved using Galerkin finite element method. A three-dimensional numerical model, called TechFlowMP model, has been developed.
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Mechanism And Control Of Sulphuric Acid Induced Heave in SoilsGuru Prasad, B 07 1900 (has links)
The escalating pollution of the environment has been one of the greatest concerns of science in recent years. Industrial advances in agriculture, expansion of chemical industries and a general change in lifestyle all over the world has lead to release of a variety of pollutants into the environment, thus contaminating the atmosphere, water bodies and many soil environments. In general, other than some natural processes, soils are increasingly being contaminated by anthropogenic sources such as leakages from waste containment facilities, accidental spills and industrial operations. Apart from affecting biotic components of the ecosystem, these pollutants greatly affect the performance, behavior and stability of the soil ecosystem, these pollutants greatly affect the performance, behavior and stability of the soil systems, thus causing severe damage to structures founded on them. The hydraulic and/or chemical alterations which allow these polluting substances to move within soil pores lead to physico-chemical decomposition processes, chemical alterations, leaching and ion exchange reactions. Such reactions could also result from natural processes such as weathering; but the effects caused by pollutants occur at faster rates. Soils are composed of clays, silts and sands. Due to charged nature of the particles and their large specific surface, engineering properties of clays are greatly affected by pollutants. The magnitude of these effects can vary significantly depending on the type of soil, the type and concentration of contaminant, duration of interaction and the environmental conditions. Hence, an understanding of contaminant-clay interactions is important for prevention of geotechnical features, if possible, or at least for planning of remedial measures. Understanding these effects and planning remedial measures requires measurement of the affected properties of polluted soils. This may involve the modification of standard test procedures or the development of new test procedures.
The main types of contaminants include inorganic acids, alkalis, sulphates, organic contaminants, toxic or phytotoxic metals and combustible substances. All of these are widely used in industries. While the adverse effects of presence of sulphate in alkaline conditions is well known, little information is available on the effect of sulphate in natural soils under acidic environments. Sulphuric acid is widely employed in the production of fertilizers, pharmaceuticals, pigments, rayon, film, iron, steel, explosives, paper and paper industry. It is also used in cleaning, etching, petroleum refining, electroplating, metallurgy, and in lead-acid batteries. Due to its widespread but often improper usage and the difficulty in safe storage, sulphuric acid is often found as a contaminant in natural soils. Sulphuric acid is also generated in natural soils by oxidation by pyrites in the presence of atmospheric oxygen. Hence, an attempt has been made in this thesis to study the behavior of soils containing different clay minerals during acid-sulphate interaction. The effect of sulphate on soils containing calcite, whose presence is quite common, has also been studied. A review of literature suggests that most common geotechnical failures due to contamination occur due to significant changes on the volume change behavior. Also, it is known that severe changes that occur in soil properties can essentially be attributed to mineralogical changes that occur during interaction with pollutants. Therefore, volume change behavior of soil and detailed mineralogical changes and the consequent morphological changes that occur in soils with acid sulphate are studied.
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The Environmental Effects of Coal FiresGarrison, Trent 01 January 2015 (has links)
There are thousands of subterranean coal fires in the world that, because of incomplete combustion, emit a wide variety of volatile and semivolatile organic compounds to the atmosphere, water, and soil at concentrations that could pose health risks to humans and wildlife. The main goals of this study were to (1) review methods that are used to characterize physical and chemical characteristics of coal-fire sites, (2) determine relationships between gas emissions and physical and chemical characteristics of coal-fire sites, using a combination of regression and multivariate statistical methods, and (3) determine the concentrations of volatile and semivolatile organic compounds in water and soil at two coal-fire sites in eastern Kentucky. More specifically:
The objective of Chapter 1 was to review past works and list technologies used over time. Eight years of coal-fire collection technologies were reviewed. A variety of methods and technologies were identified. Qualitative and quantitative preferences were noted.
The objective of Chapter 2 was to identify and list uncontrolled coal-fire variables. These variables include complete/incomplete combustion; fire temperature and size; distance to fire; relative humidity and moisture in the system; geology, geochemistry, and age of coal; condition of the mine, sampling time of day; sampling equipment differences; and human error. A secondary objective of this chapter was to determine which coal-fire gases have strong relationships by using the principal component analysis (PCA) software JMP. The strongest relationship was between CO and H2S. Temperature and CH4 were also important. This indicates that incomplete combustion and polynuclear aromatic hydrocarbon (PAH) formation are likely occurring, setting the stage for Chapter 3.
The objective of Chapter 3 was to identify and define the extent of soil and water hydrocarbon contamination at the Truman Shepherd and Lotts Creek coal fires in eastern Kentucky. No groundwater contamination was detected at either location. Soil contamination was found at both, but was much higher at Lotts Creek, potentially because of sorption onto soil organic matter (which is reduced at Truman Shepherd by an excavation attempt) and other physicochemical mechanisms. Soil contamination was localized to relatively small areas around coal-fire vents.
Based on the results, future studies should consider: Attempting to duplicate these results in other geologic regions Quantifying greenhouse gas emissions from coal fires to consider their contribution to climate change. Coal-fired power plants are regulated, but coal fires, which produce many more harmful gases, are not Determining the feasibility of an oxygen-injection system to engender more complete combustion, therefore possibly reducing harmful gases Determining the feasibility of electricity production from coal fires Adopting a consistent federal coal-fire policy
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Biorremediação de solos contaminados com hidrocarbonetos totais de petróleo - enfoque na aplicação do processo terrafermBerger, Thomas Michael January 2005 (has links)
Bodenkontaminationen durch Mineralölkohlenwasserstoffe sind ein weltweites Umweltproblem. Die Kontaminatiosquellen stehen im Zusammenhang mit Förderung, Lagerung, Transport, Verteilung und Endlagerung von Erdöl und Erdölprodukten. Brasilien beginnt zurzeit einen Prozess der Altlastenerfassung und –erkundung und in Konsequenz dessen auch die Suche nach geeigneten Sanierungstechniken. Biologische Prozesse spielen eine immer stärkere Rolle insbesondere bei der Sanierung von Bodenkontaminationen mit organischen Substanzen. Diese Prozesse gelten als “ökologisch korrekter” und sind im Vergleich mit anderen Techniken mit geringeren Kosten und technischen Aufwand durchführbar. Ziel dieser Arbeit war es, die Anwendungsmöglichkeiten der biologischen Bodensanierung mittels des Terraferm® Verfahrens unter den Umweltbedingungen des Bundesstaates São Paulo, Brasilien zu überprüfen. Zu diesem Zweck wurde der Boden einer MKW-kontaminierte Fläche (Mina de Argila) in der Raffinerie REPLAN der PETROBRÁS S/A in Paulínia -SP ausgekoffert. Es wurden zehn Bodenproben in Bezug auf ihre physikalisch-chemischen Eigenschaften MKW, PAK, BTEX, Metalle (Cr, Zn, Pb, Ni, Cu, Cd, As, Hg, Fe, Ta), Wassergehalt, pH, Korngröße analysiert. Drei Proben mit durchschnittlichen MKW-gehalten wurden zur Überprüfung der biologischen Sanierbarkeit und der Bestimmung der Kontrollparameter für den später Sanierungsdurchführung Säulenversuchen unterzogen. Insgesamt wurden 72.384t kontaminierten Bodens ausgekoffert, wovon 21.050t der Abfallklasse II (nach NBR 10004) zugeordnet wurden und direkt auf eine Mülldeponie verbracht wurden. Es wurden 51.334t der Abfallklasse 1 in die Bodenreinigungsanlage der Firmen SAPOTEC/ESTRE in Paulínia - SP mittels des Terraferm® Verfahrens behandelt. Dieses Verfahren ist darauf ausgelegt, alle für den biologischen Abbau nötigen Prozessparameter im Optimum zu halten. Die Behandlung erfolgt in Hallen auf versiegeltem Untergrund und die dabei freigesetzten Schad- und Geruchsstoffe werden gefasst und einer Abluftreinigung zugeführt. Nach der Vorbehandlung (Aussortierung von Störstoffen, Zugabe von Strukturmaterial, Durchmischung) mittels speziellem Aufbereitungsaggregat wurden insgesamt elf Behandlungsmieten aufgesetzt. Der Sauerstoffgehalt, Bodenfeuchte und Nährstoffgehalte wurden im Optimalbereich gehalten. Die Analysen und die Säulenversuche bestätigten die biologische Sanierbarkeit des Bodens. Die Abbauraten in den Säulenversuchen lagenzwischen 70,2% und 88,6% in 14 Tagen. Diese hohen Abbauraten lassen sich durch die Zusammensetzung der MKW begründen, die sich hauptsächlich aus gut abbaubaren n-Alkanen und iso-Alkanen bestehen. Die durchschnittliche Abbaurate bei den elf Behandlungsmieten lag bei 80,88%, wobei die niedrigste bei 54,71% und die höchste Abbaurate bei 97,97% lagen. Die statistische Auswertung ergab, dass sich die Mittelwerte der MKW-gehalte während der Behandlung signifikant voneinander unterscheiden (<0,01). Die im Rahmen dieser Arbeit durchgeführten Versuche bestätigen den erfolgreichen Einsatz des Terraferm® Verfahrens unter Umweltbedingungen des Bundesstaates São Paulo, Brasilien. Die starke Variabilität der Abbauraten in den Behandlungsmieten deutet aber auf einen weiteren Forschungsbedarf, insbesondere hinsichtlich des Temperatur-einflusses, hin. / Contaminações de solos com hidrocarbonetos de petróleo são um problema ambiental com abrangência mundial devido à alta demanda de produtos refinados de petróleo. As fontes são múltiplas e estão relacionadas à exploração, produção, armazenamento, transporte, distribuição e à destinação final de petróleo e seus derivados. Hoje o Brasil está iniciando um processo de avaliação e cadastramento de suas áreas contaminadas e, conseqüentemente, está procurando alternativas para a remediação das mesmas. Processos biológicos estão ganhando cada vez mais importância no tratamento, especialmente de solos contaminados com compostos orgânicos. Estes métodos são favorecidos por serem mais limpos, com custos baixos e de mais fácil aplicação em escala industrial. Assim, com o objetivo de verificar a aplicabilidade da biorremediação através do processo Terraferm® às condições ambientais do Estado de São Paulo, Brasil, foi realizada a remediação ex situ de uma área contaminada com TPH, chamada Mina de Argila na Refinaria de Paulínia – REPLAN da PETROBRÁS S/A, em Paulínia - SP. Foram analisadas dez amostras de solo contaminado em relação aos parâmetros físico-químicos TPH, PAH, BTEX, metais (Cr, Zn, Pb, Ni, Cu, Cd, As, Hg, Fe, Ta), umidade, pH, oxigênio e granulometria. Três amostras com valores médios de TPH foram submetidas a ensaios de coluna para verificação da biotratabilidade do material e para definição de parâmetros de controle do processo em escala industrial. Foram removidos um total de 72.384t de material contaminado. Deste total, 21.050t foram classificadas como resíduo classe II segundo a NBR 10004 e encaminhadas para um aterro sanitário, e 51.334t foram classificadas como resíduo classe I, sendo destinadas à estação de biorremediação das empresas SAPOTEC/ESTRE, em Paulínia - SP. O solo contaminado foi tratado com o processo Terraferm®, que visa à otimização dos parâmetros que influenciam diretamente a atividade microbiana necessária para a biodegradação. O tratamento é feito em galpões com piso impermeabilizado e com um sistema de captação e tratamento das emissões geradas durante o processo de biodegradação. Após o pré-tratamento em máquina especial, que consiste na separação dos materiais não-tratáveis, na homogeneização e na adição de material estrutural, o solo contaminado foi colocado em onze pilhas de tratamento. Os fatores chave como o teor de oxigênio, a umidade e os nutrientes foram mantidos nas faixas consideradas ótimas. A caracterização química e o ensaio de coluna comprovaram a biotratabilidade do solo. Noensaio em coluna, obteve-se taxas de degradação entre 70,2% e 88,6% em 14 dias. Essas taxas altas são explicadas pela composição do TPH que consiste, neste caso, basicamente de n-alcanos e iso-alcanos considerados de fácil degradação biológica. A taxa média de degradação obtida no tratamento das onze pilhas foi de 80,88%, sendo a menor de 54,71% e a maior de 97,97%. Na análise estatística, verificou-se que as médias das concentrações de TPH durante cada período de tratamento diferem significativamente (<0,01). O trabalho conclui que o processo Terraferm® foi aplicado com sucesso nas condições ambientais do Estado de São Paulo, Brasil. Entretanto, os resultados do tratamento mostram uma alta variabilidade das taxas de degradação nas pilhas, que indica a necessidade de novas pesquisas, especialmente sobre a influência da temperatura no processo. / Soil contaminations with petroleum hydrocarbons are a worldwide environmental problem due to the high demand for refined petroleum products. Contamination sources are multiple and related to the exploration, production, storage, transportation, distribution, and final disposal of petroleum and its derivatives. Nowadays Brazil is starting to assess and record its contaminated areas and consequently search for alternatives for their remediation. Biological processes are gaining more and more importance, specially in the treatment of soils contaminated by organic compounds. These methods are favored for being cleaner, with lower costs, and more easily applicable to industrial scale. Therefore, with the objective of verifying the applicability of bioremediation to the environmental conditions of São Paulo State, Brazil, the ex situ remediation of a contaminated area by TPH was carried out by using the Terraferm® process. The area called Mina de Argila was located in the Paulínia Refinery – REPLAN, which belongs to PETROBRÁS S/A (the country's leader in the exploration, production, and distribution of petroleum products). Ten samples of contaminated soil were analyzed in relation to the physical-chemical parameters TPH, PAH, BTEX, metals (Cr, Zn, Pb, Ni, Cu, Cd, As, Hg, Fe, Ta), humidity, pH, oxygen and texture. Three samples with average values of TPH were submitted to column tests in order to assess the material biotreatability and define the control parameters of the process on industrial scale. A total of 72,384t of contaminated soil were removed. From this total, 21,050t were classified as class II waste according to NBR 10004 and sent to a landfill, and 51,334t were classified as class I waste and sent to the bioremediation plant of the companies SAPOTEC/ESTRE, in Paulínia – São Paulo State. The contaminated soil was treated with the Terraferm® process whose purpose is to optimize the parameters which directly influence the microbial activity necessary for biodegradation. The treatment was carried out in sheds with waterproof floor and a collection and treatment system for the emissions generated in the biodegradation process. After the treatment in a special machine, which consists in separating non-treatable materials, homogenizing, and adding structural material, the soil was placed into eleven treatment piles. The oxygen content, humidity, and nutrients were kept within a range considered optimum. The chemical characterization and the column test proved the soil biotreatability. In the column test, the degradation rates were between 70.2% and 88.6% in 14 days. These high rates are due to the TPHcomposition, which in this case basically consists in n-alkenes and iso-alkenes of easy biological degradation. The average degradation rate verified in the treatment of the eleven piles was of 80.88%, the lowest being 54.71% and the highest 97.97%. In the statistical analysis, it was verified that the average concentrations of TPH during each treatment period differ significantly (<0.01). The conclusion of this work is that the Terraferm® process was successfully applied to the environmental conditions of São Paulo State. However, the treatment results show a high variability in the degradation rates of the piles, which indicates the need for further research, specially on the influence of temperature on the process.
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