Os resíduos sólidos da indústria coureira são produzidos em diferentes etapas de limpeza, classificação e ajuste da espessura do couro, e são classificados como perigosos quando gerados nas etapas posteriores ao curtimento com cromo. Os resíduos que já passaram pela etapa de curtimento apresentam elevada estabilidade, não sendo facilmente degradados. Além disso, nas etapas do acabamento molhado do couro, em especial no tingimento, corantes são utilizados para conferir cor aos artigos. Devido à necessidade de utilização de água e corantes em excesso, são gerados, nessas etapas, efluentes coloridos. Esses efluentes possuem quantidades elevadas de substâncias solúveis e coloridas que, devido ao seu potencial recalcitrante, não são facilmente removidas em sistemas convencionais de tratamento de efluentes. Neste trabalho, é apresentada uma nova proposta para o uso dos resíduos sólidos da indústria coureira antes de seu destino final, possibilitando assim uma sobrevida a esses resíduos como adsorventes alternativos de substâncias presentes em efluentes industriais do processamento do couro, em especial, os corantes oriundos das operações de acabamento molhado, com perspectivas ao reuso dos efluentes. Os efluentes oriundos da etapa de acabamento molhado de couro em escala piloto foram caracterizados. Assim, soluções aquosas sintéticas no intervalo de concentrações de corantes de efluentes foram preparadas e foi avaliada a capacidade de adsorção de dois tipos de resíduos de couro (curtido ao cromo e vegetal) em diferentes valores de pH. As isotermas de adsorção e cinética dos corantes Amarelo Ácido 194, Vermelho Ácido 357 e Preto Ácido 210 foram obtidos para os resíduos de couro curtido ao cromo no pH ideal de adsorção (entre 2 e 3). Além disso, a remoção do corante presente em efluente de tingimento (obtido em escala piloto) foi otimizada utilizando técnicas sequenciais de planejamento de experimentos. As isotermas apresentaram diferentes comportamentos, sendo do tipo C1, H2 e H3/L3 para os corantes Amarelo 194, Vermelho 357 e Preto 210, respectivamente. Os estudos dos mecanismos de transferência de massa demonstraram que a adsorção do corante Amarelo 194 é controlada pela transferência de massa na camada limite, enquanto que para os corantes Vermelho 357 e Preto 210 também foi observada a difusão no interior da partícula. Para esses dois últimos corantes, as difusividades foram da ordem de 10-9 e 10-11 m2 min-1. Os dados termodinâmicos, associados a análises instrumentais, confirmaram a natureza de adsorção por interações entre os grupos SO3 - e NO2 - dos corantes com os grupos NH(n) + do couro. Para a remoção do corante Vermelho 357 de efluentes de tingimento, uma região de ótimo foi observada para capacidade de adsorção no equilíbrio, correspondente ao pH 3,0 e temperatura entre 16 e 18 °C, sendo obsevado aproximadamente 74 mg g-1 para a concentração de 6,0 g L-1 de adsorvente. Entretanto, na região de estudo não foi observado região de ótimo para a remoção, sendo que para isso seria necessário um deslocamento no planejamento para pH inferiores a 3 e temperaturas superiores a 35 °C, o que de certa forma é inviável. Observouse que a máxima remoção em pH 3 e 35 °C foi de 75 %. O processo de remoção do corante por adsorção foi capaz ainda de reduzir a toxicidade do efluente em cerca de 90 %. / The solid wastes from the tannery industry are produced in different steps of cleaning, sorting and adjusting the thickness of the leather, and they are classified as hazardous waste when they are produced after chrome tanning. The tanned leather wastes present high stability and are not easily degraded. Moreover, in the wet leather finish, particularly during the dyeing process, dyes are used to color the items. Due to the need of using water and dye in excess, colored effluents are generated in these steps. These effluents have high amounts of soluble and colored substances that, due to their recalcitrant potential, are not easily treated in conventional eflluent treatment systems. In this research, a new proposal for the use of solid waste in the leather industry before its final destination is presented, which enables the reuse of these wastes as alternative adsorbents of substances in industrial effluents from the leather processing, particularly dyes derived from wet finishing operations, with the aim of reusing the wastewater. The effluents from the wet leather finish steps in a pilot scale were characterized. Thus, aqueous synthetic solutions in the concentration range of effluent dyes were prepared and the adsorption capacity of two types of leather waste (chrome tanned and vegetable leather) was evaluated at different pH values. Adsorption isotherms and kinetics of Acid Yellow 194, Acid Red 357 and Acid Black 210 dyes were obtained for chrome tanned leather waste in optimal adsorption pH (between 2 and 3). Furthermore, the removal of the dyes in deing wastewater (obtained in a pilot scale) was optimized by using sequential experimental design techniques. The isotherms presented different results: C1, H2 and H3/L3 types for the Yellow 194, Red 357 and Black 210 dyes, respectively. Studies on the mechanisms of mass transfer have shown that the adsorption of the Yellow 194 dye is controlled by mass transfer in the boundary layer, whereas in Red 357 and Black 210 dyes a diffusion was also observed inside the particle. For these last two dyes, diffusivities were 10-9 and 10-11 m2 min-1. The thermodynamic data, associated with instrumental analysis, confirmed the nature of adsorption by interactions between the NO2 - and SO3 - groups of the dyes with the NHn + groups of the leather. For removing the Red 357 dye in dyeing effluents, an optimum region was observed for the adsorption capacity in equilibrium, which corresponds to pH 3.0 to 3.2 and temperature between 16 and 18 °C, with about 74 mg g-1 for the concentration of 6.0 g L-1 adsorbent. However, in the study region an optimum region for the removal was not observed, and this would require a shift in planning for pH below 3 and temperatures above 35 °C, which is somewhat impractical. It was observed that the maximum removal at pH 3 and 35 °C was 75 %. The removing process the dye by adsorption was also able to reduce the toxicity of the effluent by about 90 %.

Made available in DSpace on 2016-04-01T17:54:39Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-07-15. Added 1 bitstream(s) on 2016-04-01T18:00:18Z : No. of bitstreams: 1 000577402.pdf: 782786 bytes, checksum: aeee0a8ffec3f3ca18b09361308fb3bd (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Esta dissertação tem como finalidade, apresentar e comparar dados quantitativos relativos à estação de tratamento de esgotos situada no interior de São Paulo, mais especificamente na cidade de Lençóis Paulista. A proposta do presente trabalho é apresentação de dados financeiros, particularmente retorno e risco do projeto. Dados esses que demonstram também o montante investido, e ainda, as receitas e despesas inerentes ao funcionamento do mesmo. Serão utilizados métodos de análise investimentos tradicionalmente conhecidos como valor presente líquido, taxa interna de retorno e prazo médio de retorno. Para o cálculo da probabilidade de risco do projeto, a distribuição normal será a ferramenta utilizada. É senso comum que um dos maiores fatores de degradação da qualidade da água é justamente a poluição resultante do lançamento dos esgotos sanitários coletados em corpos d'água, o que justifica a necessidade do tratamento desses esgotos, de modo a reduzir a carga poluidora antes de sua disposição final. Segundo dados do Governo Federal apenas 20,2% do esgoto sanitário coletado nos domicílios brasileiros recebem tratamento e só uma pequena parcela tem destinação final sanitariamente adequada no meio (IBGE, 2003). Desta forma, o presente estudo deste problema contemporâneo, demonstrou quantitativamente que a implantação de uma ETE é viável financeiramente, como demonstra os cálculos do valor presente líquido (VPL), taxa interna de retorno (TIR) e o prazo médio de retorno do investimento (payback). Esses métodos de avaliação de investimento foram sensibilizados com uma série que envolve a probabilidade de crescimento populacional, o que possibilitou calcular o risco do projeto, cujo percentual confirma a viabilidade do projeto, em razão do risco calculado ser muito baixo. / This dissertation has the purpose to present and compare quantitative data about waste treatment station, placed in Lençóis Paulista city, in the state of Sao Paulo. At first, this work had the intent to present financial and environmental data, however, the project not in operation, it showed only financial data. These data demonstrate the amount of money invested, as also, the revenues and expenses inherent of operation. This work used the traditional investment analysis method, like net present value, interested rate return and payback. To calculate the project risk probability, it was used normal distribution. The waste water collected is fundamental to guarantee the population's life quality. However, one of the major reason to quality's water degradation is the pollution resulted of throwing waste waters in creeks, rivers and others flow waters which justify the need to treat them, reducing the amount of pollution before their final disposal. According to Brazilian's Government statistics, only 20,2% of waste water from brazilian's homes receives proper treatment, and just a small quantity is returned in sanitary way to the environment. (IBGE, 2003). In such a way, this study esposes a contemporary problem, demonstrating quantitatively, that the implementation of ETE is financially viable, like demonstrated calculation of the net present value (NPV), internal interested rate (IRR), and payback. That investments methods evaluation was sensibility through an probability series about population growth, that make possible calculated the project risk, wich result confirm the viability of the project.

Made available in DSpace on 2014-06-11T19:32:44Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-02-02Bitstream added on 2014-06-13T19:03:14Z : No. of bitstreams: 1 lopes_mdc_dr_botfca.pdf: 4079685 bytes, checksum: d7c0ee46d4c6e815bddc9a841f8008a4 (MD5) / Universidade Estadual Paulista (UNESP) / Este trabalho teve como finalidade avaliar o tratamento da água proveniente de suinocultura na fase de reprodução por meio de um sistema de alagados construídos. Aplicou-se a água residuária via irrigação localizada por gotejamento nas culturas do milho safrinha e do sorgo. Realizou-se a caracterização química da água servida e da água residuária em quatro pontos de coletas em três épocas distintos, analisou-se também turbidez; coliformes totais e fecais; sólidos totais, dissolvidos e em suspensão; DBO; DQO; e condutividade elétrica da água. Realizou-se a caracterização química do solo e da solução do solo (extrator de solução) em quatro camadas (0-20; 20-40; 40-60; 60- 80cm) em três épocas distintas para irrigação com água residuária e para irrigação com água potável. Os experimentos foram efetuados na Fazenda Experimental Lageado, conjuntamente nos Campus da Faculdade de Ciências Agronômicas e da Faculdade de Medicina Veterinária e Zootecnia - UNESP Botucatu. Concluiu-se que o sistema de alagados construídos proporcionou redução nos teores de Coliformes totais e fecais, DBO, DQO, N, K, Cu, Zn e que a água tratada no sistema de alagados construídos pode ser utilizada via irrigação sem causar prejuízos à produtividade da cultura do milho safrinha. / This work had as purpose to evaluate swine wastewater treatment through wetland systems. Treated wastewater was applied through drip irrigation system on sorghum and corn crops. Wastewater was analyzed at four sampling points and three different times; it was analyzed turbidity, total coliform bacteria and fecal coliform bacteria, total soluble solid content, dissolved solids, suspended solids, BOD, COD, and electrical conductivity. It was carried out the chemical characterization of soil and soil solution (porous ceramic cup extractors) in four layers (0-20; 20-40; 40-60; 60-80 cm) at three distinct times for wastewater irrigation and drinkable water irrigation. Experiments were carried out at Experimental Farm Lageado, jointly in the Campuses of the College of Agronômicas Sciences and the College of Medicine Veterinária and Zootecnia - UNESP Botucatu. It was concluded that the Wetland systems decreased total coliform bacteria and fecal coliform bacteria, BOD, COD, N, K, Cu, Zn. Wastewater treated on wetland systems can be used through irrigation without causing damage to corn yield.

A sustentabilidade pode ser encarada como uma nova disciplina do conhecimento humano, agregando em seu escopo o conflito entre as dimensões ambiental, econômica e social. Esta Tese desenvolveu uma Metodologia de Avaliação da Sustentabilidade, aplicada a sistemas de tratamento de esgotos, bem como a sua aplicação na forma de um estudo de caso. A referida metodologia insere-se como uma ferramenta que pode ampliar o processo decisório, quando de um Estudo de Concepção, etapa anterior ao desenvolvimento de um projeto de uma estação de tratamento de esgotos, indo além dos critérios técnicos e econômicos. Ainda, dentro de sua estrutura, foi implementada uma plataforma participativa composta pela comunidade em estudo e por especialistas na área de saneamento ambiental. Foram comparadas três alternativas de processos de tratamento passíveis de serem implantadas em uma estação de tratamento de esgotos, situada no município de Capão da Canoa: reator anaeróbio e banhados construídos, lagoas de estabilização e banhados construídos, assim como o sistema de lodos ativados seguidos por uma etapa de desinfecção. Da análise dos referidos processos, a alternativa que contemplou as lagoas de estabilização associadas aos banhados construídos mostrou o melhor desempenho à luz das três dimensões da sustentabilidade. Com base nos resultados obtidos, observou-se que a Metodologia de Avaliação proposta, pode, efetivamente, elucidar os projetistas sobre a questão da sustentabilidade associada aos sistemas de tratamento de esgotos, bem como promover um processo decisório participativo, onde resultem soluções técnicas mais justas e transparentes. / The sustainability can be seen as a new discipline of human knowledge, adding to the scope of the conflict between the environmental, economic and social dimensions. This Thesis developed a methodology for assessment of the sustainability applied to wastewater treatment systems and its application as a case study. The methodology should be seen as a tool that can extend the decison making process, starting from a preliminary study of design, the stage preceding the development of a project from a wastewater treatment plant, going beyond the technical and economical criteria. More, inside its structure was implemented a participatory platform, compound by the community under study and by experts in the field of environmental sanitation. Were compared three alternatives of procedures that can be implanted in a wastewater treatment plant, located in Capão da Canoa: UASB reactor and constructed wetlands, stabilization ponds and constructed wetlands, as well as the activated sludge system followed by a stage of disinfection. From the analyses of those cases, the alternative that included the stabilization ponds associated with constructed wetlands showed the best performance under the perspective of the three dimensions of sustainability. Based on the results, it was observed that the assessment methodology proposed can, indeed, elucidate the designers on the issue of sustainability associated with wastewater treatment systems and promote a participatory decision process with more fair and transparent technical solutions.

A preocupação com a qualidade das águas está intensificando estudos com tecnologias avançadas para tratamento de efluentes. Uma tecnologia promissora no Brasil é a de biorreatores à membrana (MBR), pois há a possibilidade de trabalhar com altas taxas de aplicação e ainda pode obter um efluente tratado passível de reuso. Assim, o presente trabalho teve por objetivo estudar um MBR com módulo de membranas externo. Para tanto, foram estipulados os parâmetros operacionais em ensaios preliminares, tais como compactação da membrana, permeabilidade hidráulica e permeabilidade ao lodo ativado. Desta forma, efetuou-se a montagem do MBR, o qual foi inicialmente alimentado com um efluente sintético e posteriormente com efluente de curtume coletado pós-tratamento convencional. Operando com efluente sintético, obteve-se redução superior a 95% para DQO e turbidez. Com efluente de curtume pós-tratamento, obteve-se eficiência de 46%, 88%, 16%, 67% e 48% para DQO, DBO5, NTK, P-Total e cromo, respectivamente. Ademais, após 15 dias de operação, o sistema estabilizou com fluxo permeado elevado: 43 L/m².h. / The preoccupation with the quality of water resources is intensifying studies about advanced technologies for wastewater treatment. A promising technology in Brazil is the membrane bioreactors (MBR), due its capacity to operate with high application rates and may also obtains a treated effluent able to reuse. Thus, this work aimed to study a MBR with external membrane module. Firstly, it has been determined operational parameters by preliminary studies, namely: membrane compactation, hydraulic permeability and permeability to activated sludge. After that, the MBR was setting. Then, it was initially fed a synthetic wastewater and, then, with tannery wastewater collected after conventional treatment. Operating with synthetic wastewater, it was obtained a reduction of more than 95% for COD and turbidity. The operation with tannery wastewater post treatment resulted in efficiency of 46%, 88%, 16%, 67% and 48% for COD, BOD5, TKN, Total-P and chromium, respectively. Moreover, after 15 days of operation, the system has stabilized with high permeate flux: 43 L/m².h.

Muitos locais de mineração de carvão estão próximos a centros urbanos, coexistindo, nestas regiões, a drenagem ácida de minas (DAM) e os esgotos domésticos, sendo que, ambos os efluentes afetam a qualidade da água dos corpos receptores se ali lançados sem o devido tratamento. A drenagem ácida de minas afeta a qualidade da água baixando o pH, aumentando a acidez e acrescendo quantidades indesejáveis de ferro, manganês, alumínio, sulfatos e outros metais enquanto que o esgoto doméstico caracteriza-se pela presença de alcalinidade, matéria orgânica e microrganismos potencialmente patogênicos. Estudos anteriores demonstraram que a DAM pode ser utilizada como agente coagulante no tratamento físico-químico dos esgotos e, baseado nisto, o objetivo do presente trabalho foi avaliar o tratamento combinado da DAM com o esgoto doméstico de modo que também ocorra a redução dos metais e acidez presentes na DAM. O processo baseia-se no fato de que a alcalinidade do esgoto pode, pelo menos em parte, neutralizar a acidez da DAM, proporcionando uma economia no consumo de reagentes para a correção do pH. Com a elevação do pH, o ferro e o alumínio presentes na DAM sofrem hidrólise e coagulam na forma de hidróxidos dos referidos metais, separando-se da fase líquida na forma de um precipitado gelatinoso que carrea consigo os sólidos suspensos presentes no esgoto constituídos, principalmente, de matéria orgânica e microrganismos patogênicos, fósforo e nitrogênio. Assim, a metodologia do presente trabalho consistiu em realizar o tratamento em laboratório de ambos os efluentes considerando diferentes proporções de mistura. Nas condições empregadas no presente trabalho, obteve-se um efeito coagulante ótimo, em pH próximo a 7,0, para a proporção DAM:esgoto de 1:2, correspondendo a concentrações de Fe e Al acima de 80 mg/L na mistura. Para estas condições a redução de carga orgânica, nutrientes, metais e microrganismos foi elevada. A remoção de carga orgânica em termos de DQO foi 67%, a redução de nitrogênio foi de 40%, a redução de fósforo foi de 90% e a remoção de bactérias do grupo coliforme comparável aos processos convencionais de tratamento de esgoto sanitário. Dos metais presentes na DAM, o Fe e Al sofreram reduções de 99% e o Zn de 95%. O Mn, reduziu apenas 13 % na faixa de pH 7,0 utilizada no trabalho, sendo necessário tratamento adicional para atingir os limites de emissão previstos em legislação.A partir dos resultados obtidos, pode-se concluir que a mistura dos fluxos é uma alternativa para o tratamento combinado dos efluentes DAM e esgoto doméstico, onde coexistam em proporções e características físico-químicas definidas neste trabalho. / Many coal mining places are close to inhabited concentrations, where there are the acid mine drainage (AMD) and domestic sewage and both effluent affect the quality of water bodies if released without proper treatment. The AMD affects water´s quality decreasing pH, increasing acidity and the concentration of undesirable metals such as iron, manganese, aluminum, sulphates and other metals while the domestic sewage is characterized by the presence of alkalinity, organic matter and microorganisms, with possible presence of pathogenic. Previous studies have shown that the AMD can be used as an coagulant agent on physico-chemical treatment of sewage and, based on this, the aim of this work was to study the combined treatment of AMD and domestic sewage so that also occur metals and acidity reduction present in the AMD. The process is based on the fact that the sewage´s alkalinity could neutralize part of the AMD acidity, providing an economy in reagents for pH correction. At the same time, the pH increasing provides that the iron and aluminium present in the AMD, became hydrolyzed in the form of hydroxides of these metals, and provide a coagulation effect separating themselves from the liquid phase like as gelatinous precipitate which carry on suspended solids present in domestic sewage constituted mainly of pathogenic micro-organisms and organic matter, nitrogen and phosphorus. Thus, the methodology of the present work consisted of laboratory experiments considering different proportions of mixtures. Over the conditions employed in this work, the best coagulant effect was obtained with pH value around 7,0 and effluent proportion of 1:2 (DAM:sewage) corresponding to concentrations of Fe and Al above 80 mg/L in the mixture. For these conditions the organic load reduction, nutrients, metals and microorganisms was high. Removal of organic load in terms of COD was 67%, the reduction of nitrogen was 40%, phosphorus was 90% and the removal of bacteria of coliform bacteria group comparable to conventional processes for the treatment of sewage. The metals present in the AMD also was removed; the Fe and Al cut of 99% each and the Zn cut of 95%. The Mn, reduced only 13% in the range of pH 7.0 used at work, and additional treatment is needed to achieve the emission limits laid down in legislation for this metal. It was concluded that the combined treatment of AMD and sewage can be an alternative to reduce the pollutants load in sanitary effluents. From the results obtained, it can be concluded that the mixture flows is an alternative to the combined treatment of domestic sewage and DAM effluents, where they could coexist in the proportions and physico-chemical properties defined in this work.

abstract: Six high-production-volume neonicotinoids were traced through a municipal wastewater treatment plant (WWTP) and engineered wetland located downstream, in a study motivated by reports on these insecticides posing threats to non-target invertebrate species and potentially playing a role in the global honeybee colony collapse disorder. An array of automated samplers was deployed in a five-day monitoring campaign and resultant flow-weighted samples were analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) using the isotope dilution method. Concentrations in WWTP influent and effluent were 54.7 ± 2.9 and 48.6 ± 2.7 ng/L for imidacloprid, respectively, and 3.7 ± 0.3 and 1.8 ± 0.1 ng/L for acetamiprid, respectively. A mass balance over the WWTP showed no (p=0.09, CI = 95%) removal of imidacloprid, and 56 ± 6% aqueous removal of acetamiprid. In the constructed wetland downstream, a lack of removal was noted for both imidacloprid (from 54.4 ± 3.4 ng/L to 49.9 ± 14.6 ng/L) and acetamiprid (from 2.00 ± 0.03 ng/L to 2.30 ± 0.21 ng/L). Clothianidin was detected only inconsistently in the WWTP and wetland (>2 to 288 ng/L; 60% detection frequency), whereas thiamethoxam (<10 ng/L), thiacloprid (<2 ng/L), and dinotefuran (<180 ng/L) were not detected at all. Thus, imidacloprid and acetamiprid were identified as recalcitrant sewage constituents (estimated U.S. WWTP discharge of 1920- 4780 kg/y) that persist during conventional wastewater treatment to enter U.S. surface waters at potentially harmful concentrations. / Dissertation/Thesis / Masters Thesis Civil and Environmental Engineering 2015

abstract: The production and applications of engineered nanomaterials (ENM) has increased rapidly in the last decade, with release of ENM to the environment through the sewer system and municipal wastewater treatment plants (WWTPs) being of concern. Currently, the literature on ENM release from WWTPs and removal of ENM by WWTPs is insufficient and disorganized. There is little quantitative data on the removal of multi-walled carbon nanotubes (MWCNTs), graphene oxide (GO), or few-layer graphene (FLG), from wastewater onto biomass. The removal of pristine and oxidized MWCNTs (O-MWCNTs), graphene oxide (GO), few-layer graphene (FLG) and Tween™ 20-coated Ag ENM by the interaction with biomass were determined by programmable thermal analysis (PTA) and UV-Vis spectrophotometry. The removal of pristine and O-MWCNTs was 96% from the water phase via aggregation and 30-min settling in presence or absence of biomass with an initial MWCNT concentration of 25 mg/L. The removal of 25 mg/L GO was 65% with biomass concentration at or above 1,000 mg TSS/L. The removal of 1 mg/L FLG was 16% with 50 mg TSS/L. The removal of Tween™ 20 Ag ENM with concentration from 0.97 mg/L to 2.6 mg/L was from 11% to 92% with biomass concentration of 500 mg TSS/L to 3,000 mg TSS/L, respectively. A database of ENM removal by biomass was established by analyzing data from published papers, and non-linear solid-liquid distribution functions were built into the database. A conventional activated sludge (CAS) model was built based on a membrane bioreactor (MBR) model from a previous paper. An iterative numeric approach was adapted to the CAS model to calculate the result of non-linear adsorption of ENM by biomass in the CAS process. Kinetic studies of the CAS model showed the model performance changed mostly in the first 10 days after changing influent chemical oxygen demand (COD) concentration, and reached a steady state after 11 days. Over 60% of ENMs which have distribution coefficients in the database reached higher than 50% removal by the CAS model under general operational conditions. This result suggests that traditional WWTP which include the CAS process can remove many known types of ENMs in certain degree. / Dissertation/Thesis / Masters Thesis Civil and Environmental Engineering 2015

abstract: This dissertation studies the larger issue of antibiotic resistance with respect to how antibiotics are being introduced into the environment, focusing on two major anthropogenic pathways: animal husbandry for human consumption, and the recycling of wastewater and municipal sludge generated during conventional biological sewage treatment. For animal production on land (agriculture) antibiotics are often used for growth enhancement and increased feed efficiency. For animal production in water (aquaculture) antibiotics are often used as a prophylactic. I found that the same antibiotics are being used in both industries and that the same strains of human pathogens have also been isolated from both sources, expressing identical resistance mechanisms. In U.S. seafood, five out of 47 antibiotics screened for were detected at levels of 0.3 to 7.7 ng/g fresh weight. Although compliant with FDA regulations, the risk for resistance still exists, as even low antibiotic concentrations have been shown to exert selective pressure on bacteria. Similarly low concentrations of antibiotics were found in U.S. biosolids at levels of 0.6 to 19.1 ng/g dry weight. Of the five antibiotics detected, two have never been reported before in biosolids. Three have never been reported before in U.S. biosolids. Using the raw numbers obtained from antibiotic screenings in biosolids, I assessed the impact of employing four different LC-MS/MS methods, concluding that analysts should experimentally determine the most appropriate quantitation method based on the analyte targeted, matrix investigated, and research goals pursued. Preferred quantitation approaches included the isotope dilution method with use of an analogous standard and, although time and resource demanding, the method of standard addition. In conclusion, antibiotics introduced into the environment via agriculture, aquaculture, and wastewater recycling pose a combination of chemical and biological threats. Aside from exerting outright chemical toxicity to non-target organisms, antibiotic residues can promote the development of multi-drug resistance in human pathogens. Public health protection approaches to stem the risks posed by animal husbandry may include reserving drugs for exclusive, human use, decreasing their usage altogether, improving reporting efforts, reevaluating existing regulations on agricultural and aquacultural antibiotic usage, and improved risk assessment for biosolids application on land. / Dissertation/Thesis / Doctoral Dissertation Engineering 2015

Made available in DSpace on 2014-06-11T19:24:45Z (GMT). No. of bitstreams: 0 Previous issue date: 2005-04-01Bitstream added on 2014-06-13T18:52:38Z : No. of bitstreams: 1 rufato_fh_me_ilha_prot.pdf: 2126468 bytes, checksum: 13fba6f1aeeaac0b8746344e57849eac (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os reatores de leito fluidizado com circulação em tubos concêntricos têm apresentado bons resultados no tratamento de esgoto sanitário, conforme uma série de relatos da bibliografia. Entretanto, o estado atual da modelagem não oferece ferramentas consolidadas para o projeto dos reatores deste tipo, devido à complexidade do funcionamento do leito trifásico e sua interdependência com os parâmetros biológicos envolvidos. Nesse contexto, a presente pesquisa teve por objetivo caracterizar experimentalmente os efeitos da redução do diâmetro interno sobre o funcionamento de um reator de 6 metros de altura, por meio de estudos hidrodinâmicos e análises laboratoriais do esgoto afluente e efluente. O reator tem diâmetro externo de 0,25m e foi operado anteriormente com um tubo interno de 0,20m de diâmetro, o qual foi reduzido para 0,10m neste trabalho. Antes de iniciar o tratamento foram medidas as velocidades de circulação por meio de injeção de traçadores e foram determinados os coeficientes de transferência de oxigênio. O tratamento do esgoto sanitário, submetido a gradeamento prévio, foi realizado com TDH de 3 horas e concentração de meio suporte de 100g/L de areia com diâmetro médio de 0,26mm. Os resultados indicaram que a redução do diâmetro interno provocou aumento expressivo da velocidade do líquido no tubo de subida. Com isso foi possível utilizar vazões de ar tão baixas quanto 1500L/h sem risco de instabilizar o leito, enquanto que na situação anterior eram necessários cerca de 3700L/h. O processo de tratamento foi o fator limitante da vazão de ar, requerendo cerca de 2100L/h. As remoções médias de DQO, DBO e NTK situaram-se em 91,1%, 88,5% e 88,8%, respectivamente. Com o diâmetro interno de 0,20m foram obtidas, em condições de operação semelhantes, remoções de 81,7%, 88,6% e 87,0%, com uma vazão de ar de 3700L/h. Com o tubo interno de 0,10m o reator apresentou bom desempenho hidrodinâmico,... / The circulating fluidized bed reactors with concentric tubes have been presented good results in the treatment of domestic wastewater, as shown by several reports in the literature. However, the current state of the art of modeling does not offer consolidated design tools to this kind of reactors, due to the complexities of the three-phase bed behavior and their interdependence with the biological parameters involved. In this context, the objective of this research is to experimentally characterize the effect of the internal diameter reduction on the functioning of a reactor with 6 meters of height, by means of hydrodynamic studies and laboratorial analyses of the reactor’s affluent and effluent. The reactor has an external diameter of 0,25m and an internal tube with a previous diameter of 0,25m, reduced to 0,10m in this work. Before initiating the treatment the circulation velocities were measured by injecting tracers and the oxygen transfer coefficients were determined. The treatment of the previously screened wastewater was carried out with Hydraulic Detention Times (HDT) of 3 hours The solid phase (carrier particles) used was 100g/L of sand with 0,26mm of average diameter. The results indicated that the reduction of the internal diameter greatly increased the liquid’s velocity in the riser. Thus it was possible to use air injection taxes as low as 1500L/h without risk of bed settlement, while in previous situations it was necessary about 3700L/h. The air flux of about 2100L/h required by the treatment process was the restraining factor to the diminution of the air injection flux. The averaged removals of DQO, DBO, and TKN were respectively 91,1%, 88.5% and 88.8%. With the internal diameter of 0,20m in similar conditions there were obtained removals of 81,7%, 88.6% and 87.0%, with an air injection flux of 3700L/h. With the internal tube of 0,10m the reactor presented good hydrodynamic performance, also improving the settling ...