Submitted by Luciana Ferreira (lucgeral@gmail.com) on 2015-12-07T10:42:20Z No. of bitstreams: 3 Dissertação - Susane Campos Mota Angelim - 2015 (1).pdf: 18841997 bytes, checksum: 81d8b3c8746995f8815dfec4fc05909b (MD5) Dissertação - Susane Campos Mota Angelim - 2015 (2).pdf: 3115044 bytes, checksum: fb522cec32010b346517744c51a7c7c7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2015-12-07T10:45:43Z (GMT) No. of bitstreams: 3 Dissertação - Susane Campos Mota Angelim - 2015 (1).pdf: 18841997 bytes, checksum: 81d8b3c8746995f8815dfec4fc05909b (MD5) Dissertação - Susane Campos Mota Angelim - 2015 (2).pdf: 3115044 bytes, checksum: fb522cec32010b346517744c51a7c7c7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2015-12-07T10:45:43Z (GMT). No. of bitstreams: 3 Dissertação - Susane Campos Mota Angelim - 2015 (1).pdf: 18841997 bytes, checksum: 81d8b3c8746995f8815dfec4fc05909b (MD5) Dissertação - Susane Campos Mota Angelim - 2015 (2).pdf: 3115044 bytes, checksum: fb522cec32010b346517744c51a7c7c7 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2015-04-29 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / In Brazil water treatment plants (WTP) residuals are usually discharged into waterways, with negative impacts on water quality, aquatic biota and sediments, which may also pose risks to human health. This paper presents a study on real scale disposal of aluminum sludge from the settling of a WTP in a primary facultative pond, both located in Piracanjuba-GO, wishing to contribute as an alternative for residuals management. The study aimed to evaluate the effects of WTP residuals (WTPR) in the performance of the wastewater stabilization pond (WSP), in terms of quality of the effluent and volume of bottom sludge accumulated. Worked up in two identical parallel ponds, one in which WTPR was applied (test pond) and another without application (control pond) to serve as comparison of results. The study was carried out in two stages, with dosage of 37 mg TS/L in Phase 1 and 44 mg TS/L in Phase 2, totaling 125 days of application and 191 days of monitoring. It was evaluated several effluent parameters such as BOD, solids, nitrogen, total phosphorus, Escherichia coli, metals, among others. Sludge volumes in the ponds were obtained from bathymetric survey using a sludge depth meter (sludge gun) and modeling by Surfer 8.0 software. The addition of the WTPR did not impair the performance of the test pond, with minimal reduction of BOD and nitrogen. It was not possible to identify any influence of WTPR for the removal of total phosphorus of the sewage, which was attributed to high pH and low dosage. There was no statistical difference (95% confidence level) between the means of 15 parameters evaluated in two phases, except for nitrogen ammonia. There was no difference between the increases of sludge volume accumulated in the bottom of the ponds, although total solids content was higher in the test pond. This behavior was associated with particle size characteristics of the material. The study indicates technical feasibility of WTP residuals disposal in the WSP studied, revealing an alternative for its management that can also be applied in other same type systems if evaluated the specific conditions in each case. / A realidade brasileira atual é de que a grande maioria dos resíduos de ETA são lançados diretamente em cursos d'água, com impactos negativos sobre a qualidade das águas, biota aquática e sedimentos, podendo também representar riscos à saúde humana. O trabalho apresenta um estudo em escala real da disposição do resíduo do decantador da ETA do tipo convencional (ou de ciclo completo) da cidade de Piracanjuba-GO, cujo coagulante utilizado é o sulfato de alumínio, na lagoa facultativa primária da ETE Piracanjuba, visando contribuir como alternativa adequada para a gestão dos resíduos sólidos de sistemas de saneamento. O trabalho teve como objetivo avaliar os efeitos da disposição do resíduo no desempenho da lagoa quanto à qualidade do efluente líquido e ao volume do lodo de fundo acumulado. Trabalhou-se com duas lagoas idênticas em paralelo, uma de teste, onde foi aplicado o resíduo, e outra de referência, sem aplicação, para servir de comparação dos resultados. O estudo foi realizado em duas fases de aplicação do resíduo e monitoramento das lagoas, com dosagem de 37 mgSTresíduo (bs)/Lesgoto na Fase 1 e 44 mgSTresíduo (bs)/Lesgoto na Fase 2, totalizando 125 dias de aplicação e 191 dias de monitoramento. Foram avaliados diversos parâmetros físico-químicos do efluente, tais como DBO, SST, Namoniacal, fósforo total, E.coli, metais, dentre outros. Os volumes de lodo nas lagoas foram obtidos a partir de levantamento batimétrico com uso de medidor de óptico de lodo (Sludge Gun) e calculados por modelagem matemática pelo programa Surfer 8.0. A adição do resíduo de ETA não prejudicou o desempenho da lagoa facultativa de teste, com discreta redução de DBO e Namoniacal. Não foi possível apontar nenhuma influência do resíduo de ETA sobre a remoção de fósforo total do esgoto, o que foi atribuído a fatores como elevado pH e baixa dosagem. Na análise estatística dos resultados do efluente, ao nível de confiança de 95%, não foram verificadas diferenças estatísticas entre as médias dos 15 parâmetros avaliados nas duas fases, exceto para Namoniacal. Não houve diferença entre os acréscimos de volume de lodo de fundo acumulado nas lagoas, sendo que concentração de sólidos totais do lodo de fundo foi maior na lagoa de teste. Esse comportamento foi associado a características granulométricas do material. O estudo indica a viabilidade técnica da disposição do resíduo da ETA nas lagoas facultativas da ETE Piracanjuba, mostrando-se como uma alternativa ambientalmente adequada para a gestão do resíduo, que pode ser aplicada também em outros sistemas de mesmas tipologias, desde que avaliadas as condições específicas de cada caso.

Submitted by Sandra Pereira (srpereira@ufrrj.br) on 2017-06-20T16:10:30Z No. of bitstreams: 1 2010 - Cristiane Alves Foga?a.pdf: 2979226 bytes, checksum: 16723accb45fe9477013bff730b4755d (MD5) / Made available in DSpace on 2017-06-20T16:10:30Z (GMT). No. of bitstreams: 1 2010 - Cristiane Alves Foga?a.pdf: 2979226 bytes, checksum: 16723accb45fe9477013bff730b4755d (MD5) Previous issue date: 2010-03-04 / Funda??o Carlos Chagas Filho de Amparo ? Pesquisa do Estado do RJ, FAPERJ, Brasil. / The present study aimed to evaluate some limiting factors to the growth of Toona ciliata M. Roem. var. australis (Australian red cedar). In chapter I, it was evaluated the growth of Toona ciliata seedlings inoculated with arbuscular mycorrhizae fungi (FMAs), Acaulospora laevis, A. morrowiae, Entrophospora colombiana, E. contigua, Gigaspora margarita, Glomus clarum, Scutellospora calospora, S. gilmorei, S. heterogama e S. pellucida. In chapter II, it was evaluated the contents and accumulations of nutrients in Australian red cedar seedlings, submitted the complete solution, diluted solution 1/2 and 1/4. In chapter III, it was verified the symptoms of macronutrients deficiency, nutrients contents and accumulations in the Australian red cedar plants submitted the complete solution with omission of N, P, K, Ca and Mg. Chapter IV, it was observed the reply of the species the aluminum presence, using treatments with complete solution diluted the 1/4 with addition of 0, 5 and 20 mg. L-1 de Al. Between AMF tested, A. morrowiae, E. contigua e S. pellucida were most efficient in promoting the accumulation of dry weight of aerial part, development of the area leaf and phosphorous content on leaf in Toona ciliata seedlings, beyond presenting the biggest densities of esporos.50 cm-3 of substrate. And the biggest incidence of mycorrhizae settling in Toona ciliata seedlings was gotten with the species S. pellucida. The behavior of the species in reply to the use of nutritional solutions complete and diluted 1/2 and 1/4, showed that the biggest increment in height, diameter and dry weight had occurred in plants submitted at diluted solution the 1/4. The macronutrients contents and accumulations in Australian red cedar plants presented the following decreasing order: N > K > Ca > P > Mg. With regard to nutritional deficiency it verified that the omission of K was the one that more affected the development of the plant in height. The limitation in the increment stem diameter of the plants occurred in all the treatments, with exception of the complete solution. The production of total weight dry of the plants was affected in all the treatments with omission of nutrients, in according the following decreasing order: Complete Solution > - P > - Mg > - N > - K > - Ca. The initial growth of Toona ciliata seedlings was affected by the omission of all the macronutrients, having been the similar symptoms with the symptoms of other species of the same family. The immediate damages most intense and had been observed in the omission of K and Ca. Thus, the Toona ciliata species demonstrated to be demanding in macronutrients in the following decreasing order: K > N > Mg > Ca > P. The reply of the species the aluminum presence demonstrated that the growth, nutrient content and accumulation in Australian red cedar plants were stimulated in the presence of 5mg.L-1 of aluminum. The addition of 20 mg.L-1 de Al reduced the growth of the plants and macronutrients accumulation, in the following decreasing order: Ca > Mg > N > P > K. The visual symptoms of fitotoxicity had been typical to this element, beyound of the leaf with intense green coloration progressing for the yellow; the leaves oldest had progressed for yellow-brown, the edges to the limb center; and curving of new leaves. / O presente trabalho teve como objetivo avaliar alguns fatores limitantes ao crescimento de Toona ciliata M. Roem. var. australis (cedro-australiano). No cap?tulo I, avaliou-se o crescimento de mudas de cedro-australiano inoculadas com fungos micorr?zicos arbusculares (FMAs), Acaulospora laevis, A. morrowiae, Entrophospora colombiana, E. contigua, Gigaspora margarita, Glomus clarum, Scutellospora calospora, S. gilmorei, S. heterogama e S. pellucida. No cap?tulo II, foram avaliados os teores e ac?mulos de nutrientes em mudas de cedro-australiano, submetidas ? solu??o nutritiva de Hoagland & Arnon modificada, completa, dilu?da a 1/2 e a 1/4 de for?a i?nica. No cap?tulo III, verificou-se os sintomas de defici?ncia de macronutrientes, teores e ac?mulos de nutrientes nas plantas de cedroaustraliano crescidas em solu??o nutritiva com omiss?o de N, P, K, Ca e Mg. No Cap?tulo IV, observou-se a resposta da esp?cie estudada na presen?a de alum?nio, empregando tratamentos com solu??o nutritiva dilu?da a 1/4 com adi??o de 5 e 20 mg.L-1 de Al, al?m de uma testemunha Entre os fungos micorr?zicos arbusculares testados, A. morrowiae, E. contigua e S. pellucida foram os mais eficientes em promover o ac?mulo de mat?ria seca da parte a?rea, desenvolvimento da ?rea foliar e teor de f?sforo foliar em mudas de Toona ciliata, al?m de apresentarem as maiores densidades de esporos por 50 cm3 de substrato. A maior coloniza??o micorr?zica em mudas de Toona ciliata foi obtida com a esp?cie f?ngica S. pellucida. O comportamento da esp?cie em resposta ao emprego de solu??es nutritivas completas, dilu?da a 1/2 e 1/4, mostrou que o maior incremento em altura, di?metro e mat?ria seca ocorreram em plantas submetidas ? solu??o dilu?da a 1/4. Os teores e ac?mulos de macronutrientes em plantas de cedro-australiano seguiram a seguinte ordem decrescente: N > K > Ca > P > Mg. Com rela??o ? defici?ncia nutricional, verificou-se que a omiss?o de K foi a que mais afetou o crescimento em altura. A limita??o no crescimento em di?metro do coleto das plantas ocorreu em todos os tratamentos, com exce??o da solu??o de Hoagland & Arnon. A produ??o de massa seca total das plantas foi afetada em todos os tratamentos com omiss?o de nutrientes, obedecendo ? seguinte ordem decrescente: Completo> -P > -Mg > -N > -K > -Ca. O crescimento inicial de mudas de Toona ciliata ? afetado pela omiss?o de todos os macronutrientes, sendo os sintomas semelhantes com os sintomas de outras esp?cies da mesma fam?lia. Os danos mais intensos e imediatos foram observados na omiss?o de K e Ca. Assim, a esp?cie Toona ciliata demonstrou ser exigente em macronutrientes na seguinte ordem decrescente: K > N > Mg > Ca > P. A resposta da esp?cie ? presen?a de alum?nio demonstrou que o crescimento, teor e ac?mulo de nutrientes em plantas de cedro-australiano foram estimulados na presen?a de 5mg.L-1 de alum?nio. A adi??o de 20 mg.L-1 de Al reduziu o crescimento das plantas e o ac?mulo de macronutrientes, na seguinte ordem decrescente: Ca > Mg > N > P > K. Os sintomas visuais de fitotoxidez associados ? dose de 20 mg.L-1 de Al foram t?picos da toxidez a este elemento, al?m das folhas apresentarem colora??o verde intensa progredindo para o amarelecimento; com a acentua??o dos sintomas, as folhas mais velhas progrediram para amarelo-castanho, dos bordos para o centro do limbo e enrolamento ou encurvamento de folhas novas.

The importance of skin processing technologies, in the history and dispersal of humankind around the planet cannot be overstated. This area of material culture is often underrepresented as a research topic, and has been hampered, in part, by the lack of a systematic analysis methodology targeted at specifically this material type. This research aimed to develop a methodology for determining the tanning technologies in use during prehistory, from extant archaeologically recovered processed skin objects. The methodology is a product of macroscopic and microscopic observations of a large sample reference collection, used to produce a database of defining characteristics and tendencies for each of six tannage types. The sample collection is made up of twenty-two species identified as economically important from both Europe and North America. Six sample pieces of skin were taken from a single individual of each of the twenty-two species, and processed using six tanning technologies, the use of which covered a large geographic area and time frame. A second reference collection of clothing and utilitarian items, made from traditionally processed skins, was used to add a section of in-life use traces to the database of discriminating traits. The developed methodology was tested by examining archaeologically recovered and ethnographically collected skin objects, from museum collections across North America and Europe. Objects from many different preservation contexts, including wet, dry, and frozen sites were analysed to determine whether or not the discriminating traits survived interment. It was found that defining characteristics and tendencies do exist between the main tannage technologies, and can be recorded at multiple levels of observation. The analysis of skin objects in museum collections confirmed that at least some defining characteristics and tendencies survived in all preservation contexts. In addition, the preservation of in-life use traces proved to be diagnostic of not only tannage type, but small sections of chaîne opératoire and object biography as well. Overall, this research has demonstrated that archaeologically preserved objects made from processed skin can provide information about the tannage technologies in use prehistorically, as well as more detailed information such as manufacturing sequences and the conditions of use an object was subjected to. Thus, analysis of this nature can be used to access information on a more individual level than previously believed.

Les pathologies vésicales sont nombreuses et nécessitent la plupart du temps un traitement médicamenteux. Il peut alors être administré par voie intravésicale, augmentant son efficience et limitant les effets indésirables systémiques. Nous nous sommes intéressés à quatre thérapeutiques : l’alun de potassium, le chlorhydrate de lidocaïne, l’hemisuccinate de méthylprednisolone, la mitomycine C et le bacille de Calmette et Guérin (BCG) en application locale directement dans la vessie. La perméabilité de l’aluminium à travers la vessie a été étudiée au travers d’un cas clinique et des expériences ex vivo ont été réalisées pour définir les paramètres de perméabilité et proposer un algorithme de prédiction de la quantité d’aluminium absorbée dans l’organisme après irrigation intravésicale à l’alun de potassium. Cet algorithme dépend du poids du patient, de la durée de l’irrigation et du volume de la solution utilisée en irrigation vésicale. Des études de perméation ont aussi été réalisées pour le chlorhydrate de lidocaïne, l’hemisuccinate de méthylprednisolone, la mitomycine C et le BCG afin de sécuriser l’emploi de ces thérapeutiques par voie intravésicale. Les études réalisées permettent de prédire, selon les caractères physico-chimiques des molécules, la pénétration dans la membrane vésicale. Une nouvelle formulation galénique réalisée à base d’un gel thermosensible a été étudiée pour optimiser les thérapeutiques intravésicales. Des études de perméation ont été faites avec la nouvelle formulation galénique. Pour finir, une culture de cellules cancéreuses urothéliales a été mise au point et un test de viabilité a été réalisé pour la mitomycine C et le BCG / Bladder diseases are numerous and mostly require medication. Drugs can be administered by intravesical route, thereby increasing efficiency and reducing systemic side effects. We are interested in four drugs: potassium alum, lidocaine hydrochloride, methylprednisolone hemisuccinate, mitomycin C and bacillus Calmette- Guérin (BCG). Mathematical modelling of drug transport through bladder wall is proposed considering scarce literature on this route of administration. The permeability of aluminum through bladder wall was studied through a clinical case and ex vivo experiments were performed to propose a simplified algorithm for the calculation of aluminium dose absorbed in patient with impaired renal function as function of volume of 1% alum solution in the bladder, duration of intravesical irrigation and patient body weight. Permeation studies were also conducted for lidocaine hydrochloride, methylprednisolone hemisuccinate, mitomycin C and BCG to secure intravesical administration of these drugs. Practical outcome of this study could drive compounding optimisation towards improvement of safety and efficacy in patient undergoing intravesical administration. A new pharmaceutical formulation including hrydrogel has been studied in an attempt to improve treatment administered by intravesical route. Permeation studies were made with the new formulation. Finally, an urothelial cancer cells culture has been developed and a viability test was performed with mitomycin C and BCG

No description available.

No description available.

There is a current lack of accurate tools to determine the concentration of cyanobacteria in situ.  Besides, cyanobacterial blooms have to be carefully monitored in reservoirs as they are more frequent because of climate change and can lead to potential released of toxins, along with other components. This project investigates the possible use of fluorescent probes to measure the concentration of different types of organic matter released by the algae. Three different species of toxic cyanobacteria were chosen to carry out this research as they are representative of the local harmful blooms found across Australia. Furthermore, the efficiency of two different chemicals (powdered activated carbon, also known as PAC, and alum) used in drinking water treatment plants were investigated, in order to determine a method for automatic dosage adjustment in water treatment plant. The organic matter was characterized by LC-OCD and fluorescence spectroscopy and statistical analysis such as principal component analysis was performed on the generated data. General characterization of the different species was firstly performed and globally, similar comportments were observed among the three cyanobacteria species. There is indeed a general increase in the release of organic material throughout the cell’s growth phase. Results from the jar tests showed that PAC mainly targeted humic-like substances and building blocks, which are middle size particles. The average removal rate obtained was 40µg/L per mg/L of PAC added into the water. Therefore, there is indication that the decreased efficiency for the removal of the taste and odor compounds observed in certain plants can be partially attributed to direct competition of organic matter adsorption onto PAC instead of a blockage of the PAC pores by larger particles. On the other hand, alum was able to remove large particles, particularly biopolymers and also humic-substances. However, a great increase of the low molecular weight molecules at very high doses of alum was seen, which suggest that a too high dose of alum is toxic for the algae cells. Based on the bench scale testing the recommended dose of 50 mg/L seems to be optimum for the studied water treatment plant. Specific ultraviolet absorbance and dissolved organic carbon measurements were also investigated and good correlations were found between the concentration of humic-like substances and absorbance, confirming that they are good measure to assess the content of organic matter in the water. However, as the slope coefficient of the linear trend varied between the species, it was not possible to obtain a common conversion factor for all the species. Finally, one fluorophore was found in common to all the samples and is characterized by the excitation-emission wavelength: 240/440 nm. Correlations with the chromatography’s results were investigated and this component seems to match the biopolymers and humic-like substances concentrations. Furthermore, its intensity decreases continuously with the addition of PAC whereas a drop was observed at the lower doses of alum. In regards on these findings, a method for automatic chemicals dosing from the fluorescence measures was proposed. / Detta examensarbete handlar om hur dricksvattenkvalitet kan kontrolleras och övervakas i vattenreningsverk. Nu existerar  inte någon exakt metod för att bestämma koncentrationen av cyanobakterier i vatten då det finns många olika arter. Men det är viktigt att övervaka algers tillväxt in i vattenreningsverk för de kan släppa ut skadliga ämnen till dricksvattnet. De tre arter som studerats i detta projekt är giftiga. Det organiska materialet i råvattnet kan också blockera membranporer eller leda till n biprodukter, som är cancerframkallande. Till sist konkurrerar några organiska substansen med smak- och luktföreningar för adsorptionsställena hos det pulverformiga aktiverade kolet. Därför är smaken och luktföreningarna inte väl borttagna, vilket leder till kundernas klagomål. Cyanobakterier måste övervakas noggrant.                            För att bestämma biologisk och kemisk egenskap hos vatten används flera tekniker för närvarande. I examensarbetet har undersökningar med vätskekromatografi och fluorescensteknik företagits. Kromatografi användes för att klassificera den organiska substansen i mindre grupper: biopolymerer, humus substanser, byggstenar och neutralmolekyler med låg molekylvikt (LMVN). Statistisk analys med R, inklusive huvudkomponentanalys företogs på insamlade data. Fluorescensdata registrerades också och visas i en excitationsutsläppsmatris.                            Experimenten reproducerade en behandlingsprocess och undersökte effektiviteten hos två kemikalier: pulveriserat aktivt kol (PAK) och alun. Resultaten visade att humusämnen   och dess byggstenar var väl borttagna av PAK medan även biopolymerer och humusämnen var väl bortagna av alun. Emellertid var en för hög dos av alun skadlig eftersom det ledde till en ökad frisättning av LMVN. I synnerhert kunde PAK ta bort 40µg/L av både humusämnen och dess byggstenar per mg/L av PAK tillagd. Det föreslår att de är de viktigaste konkurrenterna och att endast direkt konkurrens för adsorptionsställena sker. Om det fanns blockeringsfenomen, skulle det också finnas en minskning för biopolymererna. Den optimala doseringen av alun som bestämdes för det undersökta vattenreningsverket var 50 mg/L. Det kunde ta bort 60-70% av biopolymerer och 40-50% av humusämnen.                            Specifik ultraviolett absorbans och fluorescens registrerades. Båda visade riktigt bra korrelationer med humusämnen, vilket gör de till bra verktyg för att bedöma vattenkvaliteten. Men det kräver fortfarande att arten av cyanobakterie urskiljs eftersom koefficientens lutningar var olika. De kan därför vara ett verktyg för att mäta koncentrationen av organisk material, men arten måste vara känd. Fluorescencedata visade en topp vid 440 nm. En parallellfaktoranalys utfördes på data och endast en komponent hittades gemensam i alla prover. Därför studerades den maximala fluorescensintensiteten hos denna komponent. Å ena sidan kunde vi observera en kontinuerlig minskning av intensiteten när PAK tillsattes. Det är därför möjligt att veta hur man justerar den kemiska doseringen från fluorescensintensiteterna. I slutet av examensarbetet föreslås en metod för automatisk kemisk dosering. Fluorescensprober kan ännu inte exakt indikera cellkoncentrationen. Men med flera sonder som riktar sig till olika våglängder kan de redan vara till stor hjälp för styrning vid vattenverk.

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The aluminium content of water extracts is an important aspect for the food safety of paper board, as the content indicates the ability of the paper board material to transfer aluminium to the packaged food product. Aluminium intake in humans and its health effects have been discussed for many years as some research has seen potential links between, among other things, high aluminium levels in the brain and the development of hereditary Alzheimer's.BfR's method and recommendation is the one that is generally followed by producers around the world, as there is no common international law. The method involves leaving small pieces of the paper board in Milli-Q water for 24 hours, before a content determination of Al is made in the formed water extract. In 2021, BfR halved its recommended limit for aluminium in aqueous extracts from 2 mg/L to 1 mg/L. For Stora Enso Skoghall, this led to some of their paper board grades not meeting this limit.A specific liquid packaging board grade that previously did not meet BfR's new limit was selected and alum as a flocculant was replaced with PAC, among other things. The aim was to investigate whether the change in flocculation chemical, as well as varying dosages, could affect the Al content in water extracts and whether PAC could possibly result in a lower Al content. The method for the water extracts and their effect on the final Al content have also been investigated further. This is done by performing the BfR method with artificial tap water as well, and then comparing the Al content in these extracts.PAC as a flocculant instead of alum did not result in lower levels of Al in the water extracts. Variations in dosage and production without aluminium-containing flocculants also did not significantly affect the Al content of the extracts. The type of water used in the analysis turned out to play a major role in how much aluminium migrated from the board. All samples extracted in artificial tap water resulted in Al levels less than the 1 mg/L limit. For the majority of the samples extracted in Milli-Q water, the Al levels were instead closer to 2 mg/L. The difference in Al content between the water extracts is believed to be mainly due to differences in pH and thus varying amounts of soluble aluminium.The results showed a relatively large variation between the two external laboratories used. This is believed to be mainly due to variations in method and measuring equipment, but one must also consider the small sample size that was tested and what variations it entails.

Made available in DSpace on 2014-12-17T15:01:47Z (GMT). No. of bitstreams: 1 PatriciaGSL.pdf: 4325839 bytes, checksum: ed5182708cd9548f2c8eca5937447cd6 (MD5) Previous issue date: 2008-12-22 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work aims to investigate the process of Dissolved air Flotation (DAF) for clarifying water samples with low turbidity using aluminum sulphate and Moringa oleifera seeds as coagulants. The experimental procedure was carried out in a bench scale flotation unit. The influences on the pre-treatment conditions (coagulant dosage and flocculation time) and flotation parameters (superficial application rate and recirculation rate) were evaluated considering the efficiency of the process. The efficiency was evaluated by determining the turbidity of the untreated and treated water samples. The results obtained showed that turbidity reduction can be obtained very efficiently by using DAF and the latter coagulant in low turbidity water. Using aluminum sulphate in pH?s 5.0 and 6.0 better efficiencies were obtained with low concentrations (15 mg/L), achieving values of 92% of turbidity reduction. In the case of use of Moringa oleifera better efficiencies of reduction of turbidity were reported when using a concentration of 50 mg/L in all range of pH?s, achieving 86% of reduction. The zeta potential was also determined, in an attempt to aid comprehension of the coagulation mechanisms involved. The coagulation mechanisms with Moringa oleifera seeds were shown to be adsorption and charge neutralization, as well as adsorption and bridging. Concerning aluminum sulphate, the predominant mechanisms are adsorption and charge neutralization and enmeshment in a precipitate. The results indicate that for low turbidity water, Moringa oleifera seeds could potentially be a viable substitute for aluminum sulphate / O presente trabalho tem como objetivo investigar o processo da flota??o por ar dissolvido sob press?o - FAD para clarifica??o de ?guas com baixa turbidez utilizando sulfato de alum?nio e sementes de Moringa oleifera como coagulantes. O procedimento experimental foi realizado em uma unidade de flota??o em escala de bancada. Foram avaliadas as influ?ncias das condi??es do pr?-tratamento (dosagem de coagulante e tempo de flocula??o) e par?metros de processo da flota??o (taxa de aplica??o superficial e taxa de recircula??o) na efici?ncia do processo. A efici?ncia foi avaliada pela determina??o de turbidez nas amostras de ?gua bruta e tratada. Os resultados obtidos mostraram que elevadas efici?ncias de redu??o da turbidez podem ser conseguidas com o uso da FAD em ?guas com baixa turbidez utilizando estes coagulantes. Para o sulfato de alum?nio, nos pHs 5,0 e 6,0 as melhores efici?ncias foram alcan?adas com baixas dosagens (15 mg/L), alcan?ando valores de at? 92% de redu??o. Para a Moringa oleifera, as melhores efici?ncias de redu??o de turbidez foram ? dosagem aproximada de 50 mg/L para todos os pHs, alcan?ando valores de 86% de redu??o. Determinou-se tamb?m o potencial zeta, com o objetivo de auxiliar na compreens?o dos mecanismos envolvidos na coagula??o. Os mecanismos de coagula??o com sementes de Moringa oleifera indicam ser adsor??o e neutraliza??o de cargas e adsor??o e forma??o de pontes. No que diz respeito ao sulfato de alum?nio os mecanismos predominantes s?o adsor??o e neutraliza??o de cargas e varredura. Os resultados indicam que para ?guas de baixa turbidez, as sementes de Moringa oleifera podem ser um substituto potencialmente vi?vel em rela??o ao sulfato de alum?nio