Orientador: Tsunao Matsumoto / Banca: Dib Gebara / Banca: Maria Lucia Ribeiro / Resumo: Os efluentes de curtume caracterizam-se por possuírem elevadas concentrações de compostos tóxicos, tais como: cromo, amônia, sulfatos e compostos orgânicos de baixa biodegradabilidade, por isso o tratamento desses efluentes é extremamente difícil. O presente trabalho tem como objetivo comparar a eficiência de tratamento de efluentes de curtume de duas linhas experimentais, em escala piloto, compostas por: reator UASB simplificado em forma de "Y" seguido de um Biofiltro Aerado Submerso (BF) e somente um BF, operadas simultaneamente, recebendo o mesmo efluente pré-tratado físico-quimicamente, por meio de um decantador de coluna e um floculador de manta de lodo. As linhas experimentais foram montadas junto à estação de tratamento de efluentes do curtume Fuga Couros Jales Ltda., na cidade de Jales-SP. O monitoramento das linhas de tratamento foi dividido em 4 etapas operacionais distintas: 1aetapa, a partida do sistema experimental, 2a etapa, adição do coagulante sulfato de alumino ferroso, 3a etapa, aumento da taxa de aeração nos BFs e 4a etapa, aumento do TDH nos reatores. Em cada etapa, foram analisados os seguintes parâmetros: alcalinidade total, acidez volátil, cromo total, DBObruta, DQObruta, fósforo total, nitrato e nitrito, nitrogênio total e amoniacal, oxigênio dissolvido, pH, sólidos, sulfato, sulfeto e temperatura. A eficiência média de remoção de DQO e DBO, na linha 1, foi de 66% e 73%, respectivamente. Na linha 2, a eficiência média de remoção de DQO foi de 47% e de DBO foi de 49%. A baixa eficiência de remoção de DQO, nas duas linhas, é devido as elevadas concentrações de sulfato afluentes ao tratamento biológico, resultando numa baixa relação DQO/SO4 2-, cerca de 1,2. Apesar da eficiência de remoção de DBO, na linha 1, estar próxima da porcentagem mínima estipulada na legislação estadual, cerca de 80%, o efluente das duas ...(Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The tanning effluents are characterized for its have high concentrations of toxicity compounds, such as: chromium, ammonia, sulfates and organic compound of low biodegradability, the treatment for those effluents is extremely hard. The present work has as objective compared the tanning effluents treatment efficiency of two lines experimental devices on pilot scale, composed for: line 1 - simplified UASB reactor on "Y" form following the Submerged Aerated Biofilter (BF) and line 2, only the BF reactor were operated simultaneously, receiving the same effluent pre-treated by physic-chemical devices, through a column settler and a sludge blanket flocculator. The experimental devices were installed in the tanning effluents treatment plant of the Fuga Couros Jales Ltd., at the Jales-SP city of. The treatment lines was monitoring on four different operational steps: 1st.step, start-up of the experimental system, 2nd step, addition of the coagulant ferrous aluminum sulfate in the pre-treatment devices, 3rd step, increase of the aeration rate in BFs and 4th step, increase the reactors HDT. On each step, the following parameters were analyzed: total alkalinity, volatile acidity, total chrome, BOD, COD, total phosphorous, nitrate and nitrite, total nitrogen and ammonia, dissolved oxygen, pH, solids, sulfate, sulfide and temperature. The COD and BOD removal efficiency average, in the line 1, was 66% and 73%, respectively. In the line 2, the removal efficiency average of the COD was 47% and the BOD was 49%. This low removal efficiency of COD, at two lines, is due the high sulfate inlet concentrations to the biological treatment, that resulting in a low COD/SO4 2- rate, about 1.2. In spite of the removal BOD efficiency, at line 1, reach the minimum state legislation requisite, about 80%, the effluent of the two treatment lines doesn't attempt the effluents discharges patterns, established by the environmental legislation. / Mestre

Orientador: Hamilton Cabral / Banca: Rodrigo Simões Ribeiro Leite / Banca: Fabiana Fonseca Zanoelo / Resumo: A produção de proteases de origem microbiana depende das condições de cultivo e da diversidade bioquímica de cada espécie. Estudos comparativos entre fermentação em estado sólido (FES) e fermentação submersa (FSm) usando farelo de trigo e meio sintético, respectivamente, foram realizados para a determinação dos parâmetros de produção de proteases pelo fungo Aspergillus fumigatus Fresenius. A melhor produção de protease foi em FES no período de 96 horas utilizando farelo de trigo, temperatura de 30 ºC e 1x106 esporos/5g de substrato com 1.517 U/mL. Em FSm o pico de produção foi em pH 6,0, a 30ºC, 5x105 esporos/mL de meio no período de 72 e 96 horas em meio contendo 0,5 e 0,25% de caseína, respectivamente, ambos com 40 U/mL. Conforme a produtividade dos processos fermentativos, o extrato enzimático da FES foi utilizado para estudos de purificação e caracterização bioquímica. Neste estudo, a protease purificada apresentou atividade ótima em pH 7,5 e 50ºC, sendo inibida por Fenil-metil-sulfonil-fluoreto (PMSF) e mais intensamente por antipaína (1,6 µM). Sobre efeito de íons, foi observado modulação da atividade proteolítica, principalmente com inibição por AlCl3, cuja atividade proteolítica residual foi de 18% após incubação com este íon. Na presença de Ditiotreitol (DTT) e uréia houve diminuição da atividade proteolítica, apresentando atividades residuais de 63% em 200 mM de DTT e 10% com 5 M de uréia. Comparativamente, na concentração de 0,1% de cada surfactante estudado, notou-se redução da atividade proteolítica, sendo 97% em presença de Brometo de cetil-trimetil amônio (CTAB), 79% para 4 - (1,1,3,3 - Tetrametilbutil) fenil- polietileno glicol (Triton X-100), 55% com Polyoxyethylenesorbitan monolaurato (Tween-20) e completa redução da atividade (0%) em... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The microbial protease production depends on growing conditions and the biochemical diversity of each species. Comparative studies between solid-state fermentation (SSF) and submerged fermentation (SmF) using wheat bran and synthetic medium, respectively, were performed to determine the optimum parameters for protease production by the fungus Aspergillus fumigatus Fresenius. The best protease production was in SSF within 96 hours using wheat bran, temperature 30°C and 1x106 spores/5g of substrate, with 1,517 U/mL. In SmF peak production was at pH 6.0 at 30°C, 5x105 spores/mL of media within 72 and 96 hours in medium containing 0.5 and 0.25% casein, respectively, with 40 U/mL. According to the productivity of the fermentative processes, enzymatic extract was used from SSF to study purification and biochemical characterization. In this study, purified protease showed optimum activity at pH 7.5 and 50°C, and inhibited by Phenylmethylsulfonyl fluoride (PMSF) and more intensely for antipain (1,6 µM). Concerning to the effect of ions, we observed modulation of the proteolytic activity, especially with inhibition by AlCl3, which residual activity was of 18 % after incubation with this ion. In the presence of Dithiothreitol (DTT) and ureia, we observed progressive decrease in proteolytic activity, presenting residual activities of 63% with 200 mM DTT, and 10% with 5 M ureia. Comparatively, in the concentration of 0.1% of each surfactant studied, there was a reduction in the proteolytic activity in 97% in presence of Cetyl trimethylammonium bromide (CTAB), 79% with 4-(1,1,3,3-Tetramethylbutyl)phenyl-polyethylene glycol (Triton X-100), 55% with Polyoxyethylenesorbitan monolaurate (Tween-20) and a complete inactivation in the presence of Sodium dodecyl sulfate... (Complete abstract click electronic access below) / Mestre

Lipases são enzimas que hidrolisam especificamente óleos e gorduras, podendo ser de grande interesse para vários segmentos industriais como têxtil, cosméticos, alimentícios e tratamento de efluentes com elevada carga de gordura. O objetivo do presente trabalho foi avaliar a produção de complexos enzimáticos lipolíticos produzidos por microrganismos isolados de um sistema de tratamento biológico de efluentes de um hotel, visando obter lipases com potencial para emprego em processos biotecnológicos. Para a seleção do microrganismo lipolítico foram utilizados 65 isolados bacterianos oriundos do efluente bruto e tratado da wetland e da caixa de gordura do restaurante do hotel. A produção de lipase foi testada em placa em meio de cultivo acrescido de azeite de oliva e rodamina B, incubados a 25°C e 30ºC por 24h-48h e as placas observadas sob luz UV 350 nm. Deste total de isolados, sete oriundos da wetland e 22 isolados da caixa de gordura foram positivos para lipase, pois apresentaram halos fluorescentes alaranjado. Os isolados foram testados novamente em placa, porém numa condição mais estressante em termos de nutrientes para induzir a utilização do azeite e assim selecionar as melhores produtoras de enzimas Desses, 12 isolados apresentaram atividade lipolítica e aquele que apresentou halo mais evidente e maior foi selecionado para ensaios com crescimento em cultura submersa em agitador orbital e biorreator em três substratos diferentes (azeite de oliva, óleo de semente de uva e óleo de canola) para a determinação da atividade enzimática. As bactérias lipolíticas identificadas bioquimicamente foram do gênero Enterobacter, Acinetobacter, Pseudomonas, Klebsiella e Burkholderia. Os ensaios em cultura submersa em biorreator nos três substratos avaliados apresentaram a máxima produção de lipase após 12 horas de cultivo; azeite de oliva 0,358 U/mL.min-1, óleo de semente de uva 0,352 U/mL.min-1 e óleo de canola 0,348 U/mL.min-1. Em cultivo submerso em agitador orbital, o meio de cultivo na presença de Tween 80, apresentou melhor atividade enzimática que o meio de cultivo sem a presença do emulsionante. A identificação molecular do isolado apresentou identidade com o gênero Acinetobacter baylyi. A análise por SDS-PAGE sugere uma lipase com massa molecular de 35 kDa. / Lipases are enzymes that specifically hydrolyze oils and fats and may be of great interest to various industrial segments such as textiles, cosmetics, food and effluent treatment with the high fat load. The aim of this work was to evaluate the production of lipolytic enzymatic complexes produced by microorganisms isolated from a biological treatment system of effluents of a hotel, aiming to obtain lipases with potential for use in biotechnological processes. To select the best lipolytic microorganism, we used 65 bacterial isolates, recovered from the raw and treated effluent of the wetland system and from the fat tank of the hotel restaurant. Lipase production was evaluated in culture medium supplemented with olive oil and rhodamine B, incubated at 25°C and 30°C for 24h-48h. The grown colonies were observed under UV light at 350 nm. Out of that, seven isolates from wetland and 22 isolated from the fat tank were positive for lipase as they exhibited orange fluorescent halos. The isolates were again seeded on medium with a stressful nutrient condition to induce the use of olive oil and thus select the best enzyme producers Of these, 12 isolates presented lipolytic activity, and the one that showed the most evident halo was selected for assays in submerged culture in an orbital shaker and bioreactor using three different substrates (olive oil, grape seed oil, and canola oil). The lipolytic bacteria identified were of the genus Enterobacter, Acinetobacter, Pseudomonas, Klebsiella, and Burkholderia. The assays run in the bioreactor showed the maximum lipase production after 12 hours of culture with the three substrates evaluated; 0,358 U/mL.min-1 in olive oil, 0,352 U/mL.min-1 grape seed oil, and 0.348 U/mL.min-1 canola oil. The results obtained in an orbital shaker showed better enzymatic activities in the presence of Tween 80 on the culture medium. The molecular identification showed identity with the genus Acinetobacter baylyi. Analysis by SDS-page suggests a lipase with a molecular mass of 35 kDa.

Estudos anteriores mostraram que a soldagem de aço USI-SAC-50 com adição de pó metálico pode promover o aparecimento de microfases que interferem nas propriedades mecânicas. Este trabalho, teve o objetivo de estudar os efeitos de variações nos consumíveis, aporte de calor e do tratamento térmico pós-soldagem na diminuição ou eliminação das microfases. Chapas de aço USI-SAC-50 foram soldadas por arco submerso com adição de pó metálico utilizando-se fluxos de soldagem BX-200 e OK-1071,arames de soldagem EM-12K e EB-2 e aportes de calor de 4,8 kJ/mm e 3,6 kJ/mm. Tensão e corrente foram mantidas em 34 V e 600 A, respectivamente. Após a soldagem, metade das chapas foi submetida a um tratamento térmico de alívio de tensões a 580ºC por 1 h. Foram realizados ensaios mecânicos de dureza, tração a -10ºC e CTOD a -10ºC, assim como foram realizadas metalografias preto e branco e coloridas para identificação e quantificação de fases. As composições químicas obtidas nos cordões de solda foram adequadas para que a quantidade de ferrita acicular presente assegurasse as boas propriedades mecânicas. As mudanças na composição química, em relação à trabalhos anteriores, ocasionadas pela variação dos fluxo e as variações nos aportes de calor promoveram uma sensível diminuição na quantidade de microfase para faixa de 2,5 a 10%. Entre os cordões ensaiados para avaliação de CTOD aquele com maior teor de austenita retida apresentou um CTOD menor, mostrando a influência dessa fase sobre a tenacidade. Também o tratamento térmico de alívio de tensões contribuiu para a diminuição da quantidade de microfase para a faixa de 0 a 1,5%, sendo que a microfase restante apresentou uma forma esferoidal. / Previous studies showed that the welding of steel USI-SAC-50 with addition of metal powder can promote the appearing of one phase that interfere in the mechanical properties. This work had the objective of studying the effects of variations in the consumable ones, contribution of heat input and of the thermal treatment in the decrease or elimination of this phase. Plates of steel USI-SAC-50 were welded by submerged are weld with addition of metal powder being used welding fluxes BX-200 and OK-1071, welding wires EM-12K and EB-2 and heat inputs of 4,8 kJ/mm and 3,6 kJ/mm. Tension and current were maintained in 34 V and 600 A, respectively. After the welding, half of the plates was submitted to a thermal treatment of relief of tensions to 580ºC for 1 h. Mechanical tests of hardness, traction to -10ºC and CTOD to -10ºC were carried out, as well as black and white and colored metalographies were carried out for identification and quantification of phases. The chemical compositions obtained in the weld beads they were appropriate so that the amount of acicular ferrite present assured the good mechanical properties. The changes in the chemical composition, in relation to previous works, caused by the variation of the fluxes and the variations in the heat inputs they promoted a sensitive decrease in the amount of microphase for strip from 2,5 to 10%. The thermal treatment of relief of tensions also contributed to the decrease of the amount of microphase for the strip from 0 to 1,5%, and the remaining microphase presented a spherical shape.

Dissertação(mestrado) - Universidade Federal do Rio Grande, Programa de Pós-Graduação em Engenharia e Ciência de Alimentos, Escola de Química e Alimentos, 2007. / Submitted by Caroline Silva (krol_bilhar@hotmail.com) on 2012-09-25T19:06:21Z No. of bitstreams: 1 microsoft word - dissertao.final.pdf: 515857 bytes, checksum: afa0c33effce4f7fb4a24ce581f95202 (MD5) / Approved for entry into archive by Bruna Vieira(bruninha_vieira@ibest.com.br) on 2013-06-18T18:32:39Z (GMT) No. of bitstreams: 1 microsoft word - dissertao.final.pdf: 515857 bytes, checksum: afa0c33effce4f7fb4a24ce581f95202 (MD5) / Made available in DSpace on 2013-06-18T18:32:39Z (GMT). No. of bitstreams: 1 microsoft word - dissertao.final.pdf: 515857 bytes, checksum: afa0c33effce4f7fb4a24ce581f95202 (MD5) Previous issue date: 2007 / Os biossurfactantes compreendem uma classe importante de compostos anfipáticos de origem microbiana. A bactéria gram negativa Pseudomonas aeruginosa é conhecida por sua habilidade de produzir biossurfactante do tipo ramnolipídio a partir de diversas fontes de carbono. A investigação da produção por novas linhagens pode resultar em processos mais eficientes, maiores rendimentos e biossurfactantes com características distintas, sendo aplicados em várias indústrias, tais como as indústrias farmacêutica, de cosméticos, de petróleo e de alimentos. Por outro lado, com o maior consumo de petróleo e derivados, cresceu a exposição de ambientes a possíveis acidentes relacionados à produção, transporte, carga e descarga desses materiais, sendo cada vez mais necessário buscarem-se alternativas tecnológicas para a recuperação desses ambientes. A biorremediação pode ser definida como o uso das potencialidades dos microrganismos em degradar compostos poluentes, reduzindo o grau de contaminação ou mesmo descontaminando ambientes degradados. Entre as técnicas disponíveis, a bioestimulação é uma das mais usadas, em que a microbiota nativa é estimulada pela adição de nutrientes e coadjuvantes como os biossurfactantes. Este trabalho teve como objetivo estudar a produção de ramnolipídios de Pseudomonas aeruginosa isolada de resíduos de pescado capturado no extremo sul do Brasil, utilizando diversas fontes de carbono (óleo de soja, borra de óleo de soja, óleo de pescado, glicerol e glicose) e fontes de nitrogênio (nitrato de sódio, nitrato de amônio, uréia e sulfato de amônio), bem como diferentes relações C/N. O biossurfactante foi caracterizado quanto à influência de fatores físicoquímicos na formação de emulsões. A degradação de petróleo em solo retirado de local próximo a um oleoduto, por técnicas de bioestimulação, com e sem a utilização do biossurfactante, também foi estudada. Os cultivos microbianos foram realizados em triplicata, sendo conduzidos em incubadora rotatória a 30°C e 180rpm, por um período de 96 horas. Pelo teste de Tukey, a 95% de confiança, o óleo de soja (40g/L) e o nitrato de sódio (8g/L) foram as melhores fontes de carbono e nitrogênio, respectivamente, obtendose, com uma relação C/N 22, 0,94g/L de ramnose e índice de emulsificação de 62,1%. Com uma relação C/N 100 foram produzidos 1,42g/L de ramnose e índice de emulsificação de 60,7%, indicando que a produção é favorecida em condição nitrogêniolimitante. A formação de emulsões estáveis foi melhor em concentrações salinas menores que 0,5%, pH na faixa de 6-9 e temperaturas na faixa de 35-40°C, mantendo cerca de 80% de sua atividade original para salinidade de até 3% e 120 min de exposição a 100°C. Quanto à biorremediação, os melhores resultados foram obtidos nos tratamentos com adição de nutrientes e adição de nutrientes mais biossurfactante, com 90,4% e 80,9% de remoção de hidrocarbonetos totais de petróleo, respectivamente, demonstrando efetiva melhoria em relação ao controle (42,2%), havendo uma clara relação entre a dinâmica da microbiota local e a biodegradação. / Biosurfactants consist of an important class of amphipathic compounds of microbial origin. The Gram-negative bacteria Pseudomonas aeruginosa is known for its ability to produce rhamnolipid-type biosurfactant from diverse carbon sources. The investigation of the production by new strains can result in more efficient processes, greater yields and biosurfactants with distinct characteristics, being applied in various industries, such as pharmaceuticals, cosmetics, oils and foods. On the other hand, with the huge consumption of petroleum and its derivatives, the exposure of environments to possible accidents related to the production, transport, loading and unloading of these materials has increased, making it necessary to search for technological alternatives to restore of these environments. Bioremediation can be defined as the use of the potential of microrganisms in degrading pollutant compounds, reducing the degree of their contamination or decontaminating degraded environments. Among the available techniques, biostimulation is one of most commonly used, where native microbiota is stimulated by the addition of nutrients and amendments as surfactants. This work had as its objective to study the production of biosurfactant from a strain of Pseudomonas aeruginosa isolated from fish samples captured in the extreme south region of Brazil, using diverse carbon sources (soybean oil, soybean oil soapstock, fish oil and glycerol) and nitrogen sources (sodium nitrate, ammonium nitrate, urea and ammonium sulphate), as well as different C/N ratios. The biosurfactant was characterized taking into account the influence of physio-chemical factors in emulsion formation. The degradation of oil from the soil removed from a place next to a pipe-line in the region by different biostimulation techniques, with and without the use of the biosurfactant, also was studied. The microbial culture assays, carried out in triplicate, were conducted in a rotary shaker at 30°C and 180rpm, for a period of 96 hours, and the results analyzed by the Tukey test. The soybean oil (40g/L) and the sodium nitrate (8g/L) were the best sources of carbon and nitrogen, respectively, obtaining with a C/N 22, 0.94 g/L of rhamnose and an emulsification index of 62.1%. With a C/N ratio 100, 1.42 g/L of rhamnose and an emulsification index of 60.7% were produced, indicating that the production is favored in a nitrogen-limiting condition. The formation of stable emulsions was better in saline concentrations less than 0.5%, pH in the range of 6-9 and temperatures in the range of 35-40°C, maintaining about 80% of its original activity for salinity up to 3% and 120 min of exposure at 100°C. For bioremediation, the best results were obtained in the treatments with addition of nutrients and addition of nutrients with more biosurfactant, with 90.4% and 80.9% of TPH removal, respectively, demonstrating effective improvement in relation to the control (42.2%), having a clear relation between the dynamics of local microbiota and the biodegradation.

O pós-tratamento apresenta-se como uma forma de adequar o efluente de reatores anaeróbios aos requisitos da legislação ambiental e propiciar a proteção dos corpos receptores. O trabalho foi desenvolvido com a finalidade de avaliar a viabilidade técnica da utilização do processo de ozonização quando aplicado a um sistema combinado composto por reator UASB seguido por biofiltro aerado submerso. No sistema foi avaliada a operação de quatro biofiltros, dois com carvão ativado e dois com anéis de polietileno. Para verificar a influência da oxidação com ozônio na biodegrabilidade somente um dos biofiltros preenchidos por cada material suporte recebeu efluente ozonizado. Os menores valores de concentração de DQO foram encontrados nos filtros preenchidos com carvão ativado granular, com valores de até 14,00 mg/L, para os dois tipos de afluentes, ozonizado e não-ozonizado. Contudo, considerando eficiência de remoção de DQO para todo período de operação os biofiltros preenchidos com anéis de polietileno se mostraram mais eficazes, com eficiência de até 80%. Os resultados evidenciaram a ocorrência de nitrificação em todos os sistemas, uma vez que houve consumo de NTK e de alcalinidade, com queda de pH; produção de nitrato. / The post-treatment is presented as an alternative to adjust the effluent of anaerobic reactors to the requirements of the brazilian environmental legislation. The work was developed with the purpose to evaluate the viability of the use of the ozonization process when applied to a system composed by a reactor UASB followed by submerged aerated biofilter. In the system the operation of four biofilters was evaluated, two fillet with granular activated carbon (GAC) and two with polyethylene rings. To check the influence of the oxidation with ozone in biodegradability, only one of the biofilter with each support material received ozonized effluent. The lowest values of DQO concentration had been found in the filters with GAC, with values of up to 14,00 mg/L, for the two types, ozonized and not-ozonized. However, considering the DQO removal efficiency for all operation periods the biofilters with polyethylene rings were more efficient, with efficiency of up to 80%. The results had evidenced the occurrence of nitrification in all the systems, a time that had NTK and alkalinity consumption, with fall of pH and nitrate production.

Orientador: Antonio Carlos Bannwart / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências / Made available in DSpace on 2018-08-21T23:41:35Z (GMT). No. of bitstreams: 1 Bragantini_MauroFernando_M.pdf: 5693941 bytes, checksum: bef9d874ab134a24eff92a6991db0e51 (MD5) Previous issue date: 2012 / Resumo: As bombas centrífugas submersas (BCS) são largamente empregadas para elevação artificial de petróleo, sendo, na sua configuração básica, acionadas por motores elétricos. Os motores elétricos são o elo mais sensível deste equipamento, apresentando baixo MTBF (Mean Time Between Failure), ocasionando intervenções custosas para o seu reparo e/ou substituição nas plataformas off-shore de produção de petróleo. O acionamento da BCS por outro meio é uma alternativa para aumento deste MTBF e a utilização de uma turbina hidráulica como força motriz uma possibilidade já viabilizada tecnicamente. Os produtos existentes no mercado, neste arranjo, BCS+Turbina, são denominados de HSP (Hydraulic Submersible pump). Devido às características construtivas da BCS, múltiplos estágios em série, diâmetro externo reduzido e acoplamento direto com o acionador, o projeto da turbina deve ser alinhado com estes requisitos. Este trabalho investiga a definição da carga de certa BCS bombeando óleo, analisa os diferentes métodos de predição do comportamento desta mesma BCS funcionando como turbina como opção de acionamento, estabelece as condições de projeto deste arranjo, o constrói, o ensaia e compara os resultados com as metolodogias de predição pesquisadas / Abstract: Bore-hole electrical submersible pumps (ESP) are largely used as oil artificial lift alternative. Electrical motor is the most sensitive component of this equipment presenting low MTBF (Mean Time Between Failure) causing high cost operations to fit or replace it on oil production off-shore platforms. ESP driving by another mean is an alternative to increase MTBF and a hydraulic turbine as driver is a technical possibility already available. Market existing products on this arrangement are called HSP (Hydraulic Submersible pump). Due to ESP constructive characteristics like multiple stages, reduced bore-hole diameter and direct coupled to the driver the turbine design should meet these requirements. This work investigates certain SP (Submersible Pump) load when pumping oil and the different prediction methods of this same SP running as turbine as drive option, also establishes the design conditions of this arrangement, builds it, tests it and compares the results against the researched prediction methodologies / Mestrado / Explotação / Mestre em Ciências e Engenharia de Petróleo

Grunda, näringsrika sjöar förekommer i två stadier: antingen ett med grumligt vatten och hög biomassa av växtplankton, eller ett med klart vatten och riklig undervattensvegetation. Det klara stadiet är eftersträvansvärt eftersom det skapar goda förutsättningar för en rad ekosystemtjänster, inklusive vattenkvalitet, rekreation och förutsättningar för biodiversitet. Vid eutrofiering, d v s ökat tillskott av näringsämnen, kvarstår det klara stadiet tills näringsbelastningen blir så hög att sjön övergår till ett grumligt stadium. Sjön Tåkern, i Östergötland, har under de senaste åren blivit alltmer eutrofierad och kalkning av vattnet har diskuterats som en möjlig åtgärd för att bevara det klara stadiet som sjön numera befinner sig i. Undersökningar om kalkning av eutrofierade sjöar har gjorts tidigare, men det har varit få studier av effekterna av kalkning på undervattensvegetation, substratlevande djur och påväxtalger. För att undersöka detta, gjordes ett fält- och ett laboratorieexperiment inriktade på effekter på överlevnad av vattengråsugga, Asellus aquaticus, fysiologisk status (halten klorofyll a) i kransalgen Chara globularis och tillväxt av nyetablerade påväxtalger i sjön Tåkern. Resultaten visar att A. aquaticus hade lägre överlevnad efter kalkning till pH 10 i laboratorieexperiment, men i fältförsöket hade kalkning till detta pH inte någon inverkan. C. globularis hade en högre halt klorofyll a efter kalkning till pH 10 i laboratorieexperimentet, men i fältexperimentet hade kalkning ingen effekt på halten klorofyll a. Påväxtalger hade en lägre tillväxthastighet efter kalkning i fältexperimentet. Slutsatsen är att kalkning kan vara en metod för att motverka eutrofiering av sjön Tåkern. Några inkonsekvenser mellan mesokosm- och laborationsresultaten tyder på att fler studier behövs göras för att undersöka hur kalkning till pH 10 påverkar bentiska organismer. / Shallow, nutrient-rich lakes can occur in two alternative states: either a turbid water state with high biomass of phytoplankton, or a clear water state with abundant submerged vegetation. The clear water state is worth striving for because it creates good conditions for a range of ecosystem services and biodiversity. Lake Tåkern, Östergötland, has in recent years become increasingly eutrophic and liming has been discussed as a method to reduce the phosphorus level and maintain, or trigger a shift to, the clear water state. Investigations regarding the effects of liming of eutrophic lakes on phosphorus level and plankton have been performed in the past, but few studies have examined the effects on submerged vegetation, benthic invertebrates and periphyton. To study this, a field and a laboratory experiment were performed to examine how liming to pH 10 affects survival of the benthic invertebrate Asellus aquaticus, the chlorophyll a content in the stonewort Chara globularis and growth of periphyton. Survival of A. aquaticus was not affected in a field mesocosm experiment in Lake Tåkern, but decreased after liming in a laboratory experiment. The chlorophyll a content of C. globularis was not affected in the field experiment but higher than in the controls in the laboratory experiment. Growth of periphyton was reduced in the field experiment. Based on the field experiment, effects on A. aquaticus and C. globularis were negligible, but the laboratory experiment indicate that liming to pH 10 may under certain conditions affect benthic organisms. The conclusion is, however, that liming can be a suitable method to counteract the eutrophication of Lake Tåkern. Some inconsistencies between the field and laboratory results suggest that more studies needs to be made to see how liming to pH 10 affect benthic organisms.

This study, which includes both experimental and numerical-modelling components, investigates the potentially dangerous conditions that can often occur when low-head dams (or weirs) are overtopped and ‘submerged’-type hydraulic jumps subsequently form downstream of them. The combination of high local turbulence levels, air entrainment, and strong surface currents associated with submerged jumps pose a significant risk to safety of boaters and swimmers. In this study, a wide range of flow regimes and different experimental conditions (i.e. crest length and downstream apron elevation) were considered. The experimental phase involved physical model testing to determine: (i) the hydraulic conditions that govern submerged jump formation, and (ii) the hydrodynamic characteristics of the submerged vortex. The numerical model, developed using OpenFOAM, was validated with the obtained experimental data. This research seeks to help develop improved guidelines for the design and safe operation of low-head dams. The experimental phase of the study involved physical model testing to determine: (i) the hydraulic conditions that govern submerged jump formation, and (ii) the hydrodynamic characteristics of the submerged vortex. The numerical modelling work involved using interFoam (OpenFOAM toolbox) for simulating the experimental results. InterFoam is an Eulerian 3-D solver for multiphase incompressible fluids that employs the Volume of Fluid approach (VOF) to capture the water-air interface. The developed numerical model was subsequently validated using the experimental data collected and processed by the author of this study. The range of tailwater depths associated with submerged hydraulic jump formation is dramatically reduced when a broad-crested weir is coupled with an elevated downstream apron, especially under high flow rate conditions. However sharp-crested weirs induced vortices which displayed reduced velocities and decreased spatial development, which were judged to be safer than broad crest lengths under the same discharge conditions. The classical formulation for the degree of submergence was not explicative when used to evaluate “how submerged the vortex was”. Consequently, a new normalized formulation which compares the local tailwater depth to the lower and upper tailwater limits for the submerged hydraulic jump is proposed. The numerical model developed for this study demonstrated the existence of residual turbulent kinetic energy at downstream sections located within the vortex’s extension, at instants coinciding with the presence of a fully formed roller. This turbulent energy is arguably responsible for the stationary nature of the vortex under constant flow conditions. Residual vertical and horizontal velocities at points located within the vortex’s domain are indicative of the existence of the free surface current.

A harsh, cold, and icy environment is of no surprise to the conditions of a winter climate, where the wide use of de-icing salts on roads and highways allows for the initiation of chloride-induced corrosion of the reinforcement of concrete structures; a reduced service life, loss of structural integrity, visible damages, and ultimately structural failure are among the many unwanted effects of rebar corrosion. Chloride ingress into concrete has been extensively studied for the last four decades; however, most of the relevant research to date does not take into account the effects of sustained loading on chloride transport properties. Therefore, the objectives of this study were to investigate the influence of sustained compressive and tensile stresses on chloride ingress into concrete, and ultimately to understand what the effect of sustained stress is on chloride penetration depth, on chloride concentration by % weight of concrete, and on apparent diffusion coefficients by comparing results to those of unloaded control specimens. To achieve these objectives, six post-tensioned and four non-reinforced control concrete beams were constructed with different water-to-cement (w/c) ratios and completely submerged in a 4-5% de-icing salt (NaCl) solution for 12 weeks, allowing chloride transfer to be completely governed by continuous diffusion. The effects of supplementary cementing material on chloride ingress are also studied. Concrete beams were post-tensioned to induce variable sustained compressive and tensile stresses along the beam. After 12 weeks of exposure, beams were fractured at specific locations and sprayed with a 0.1N silver nitrate (AgNO3) solution to determine average penetration depths; chloride concentration profiles were obtained from potentiometric titration of grinded powder samples. Apparent chloride diffusion coefficients were then obtained from the results of spraying AgNO3 and titration, the latter by non-linear regression curve-fitting to Fick’s second law of diffusion. A good agreement between results from both methods reveals that the use of AgNO3 in field is acceptable in predicting the rate of chloride ingress in concrete sustaining stress. The chloride diffusivity for each profile, relative to that of the unstressed section, was related to the compressive and tensile stresses in the concrete section. The experimental results indicate the dependence of chloride ingress and concentration on the type and level of sustained stress. An analysis of the results to study the effects of the w/c ratio using colourimetric (silver nitrate spray) and potentiometric titration methods was also completed.