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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Removal of turbidity and organic matter from raw water using nonwoven and biofilter

Liao, Tzu-Hsiang 29 June 2011 (has links)
Extreme rainfall in raw water resource is greatly caused by climate change in Taiwan now. When typhoons are occurred, the turbidity in raw water is caused a high concentration frequently. In Taiwan the raw water, used by water treatment plants, comes from majorly river water. Most water treatment plants use chlorine disinfection; the disinfection process also produced excess disinfection by-products when raw water contains high turbidity and organic matter. In recent years, membrane method is widely being applied in water purification, but shortcomings were the higher price and not longer life. The purpose of this study is to investigate the treatment efficiency of turbidity, TOC, AOC, THMs and THMFP by using cheap nonwoven and biofilter (denoted as This System). In this study we used the base weight of 35 g/m2 nonwoven in filtration experiments for turbidity removal. Experimental results show turbidity removal by this system was nearly 90% when inlet turbidity is under moderate condition. The turbidity of treated water in effluent is all below 2 NTU that is compliance with national drinking water quality standards. Turbidity removal was about 90% using nonwoven with 21 pieces. Removal of organic matter is about 39% using biofilter when influent was in the low concentration of TOC. The removal rate is about 77% when the high TOC concentration in influent. In removal of TOC, TOC removal of raw water (I) was about 26.41%. The concentration of TOC was reduced from1169.9 £gg/L to 856.9£gg/L. The TOC removal of raw water (¢º) was about 19.65%. The concentration of TOC was reduced from 680.8£gg/L to 521£gg/L. The TOC removal of raw water (¢») was about 48.78%. The concentration of TOC was reduced from 1819 £gg/L to 936.5£gg/L. In removal of AOC, the removal rate of raw water (I) was about 50.83%. The concentration of AOC was from 59.51 £gg acetate-C/L to 28.42 £gg acetate-C/L). The removal of raw water (¢º) was about 50.97%. The concentration of AOC was from 73.08 £gg acetate-C/L to 35.8 £gg acetate-C/L. The removal of raw water (¢») was about 65.07%. The concentration of AOC was from 226.60 £gg acetate-C/L to 81.19 £gg acetate-C/L. The suggested limit level of AOC in treated water is 50£gg acetate-C/L Longer empty bed contact time of biofilter should enable the concentration below 50 £gg acetate-C/L. Removal of AOC increased with increased the empty bed contact time of biofilter . In removal of THMs and THMFP (denoted as precursors), the raw water (I) : THMs removal was about 50.22%. The concentration of THMs was reduced from 34.64 £gg/L to 17.56 £gg/L. The raw water (¢º): THMFP removal was about 46.83%. The concentration of THMs was reduced from 34.18 £gg/L to 18.27 £gg/L. The raw water (¢»): THMFP removal was about 51.81%. The concentration of THMFP was reduced from 81.49 £gg/L to 39.25 £gg/L. They were all lower than national standard of drinking water (THMs 80 £gg/L). Thus, this system can effectively remove turbidity, TOC, THMs and THMs precursors in raw water.
2

Microbial treatment of textile wastewater applicable in developing countries

Forss, Jörgen January 2013 (has links)
No description available.
3

Traitement d'effluents polysiloxaniques dans des matrices aqueuses salines : potentiel de la nanofiltration et de l'oxydation biologique / Siloxanes removal in salines aqueous effluent : nanofiltration and biological oxidation potential

Boedec, Arthur 01 March 2018 (has links)
La production industrielle des silicones génère des effluents aqueux contenant des siloxanes et polysiloxanes, chargés en sels à divers stades de la filière. Dans une perspective de développement durable et pour tenir compte des préoccupations grandissantes autour de l'impact environnemental des rejets industriels, des procédés d'épuration sont recherchés. L'objectif de cette étude est d'évaluer les performances de deux procédés, nanofiltration et oxydation biologique, pour le traitement des effluents aqueux polysiloxaniques. Des expériences de nanofiltration frontale ont été réalisées. Les essais préliminaires avec des solutions synthétiques, mélange d'eau et des siloxanes, ont montré une rétention quasi-totale des siloxanes dans tous les cas testés. Des expériences ont ensuite été menées avec des effluents représentatifs des effluents usines de différentes compositions pour évaluer la robustesse du procédé. Nous avons montré que la nanofiltration réduit efficacement la charge organique globale de l'effluent et réduit significativement la concentration en siloxane. La dilution provoque une diminution de l'abattement du COT et de la rétention des siloxanes mais la qualité du perméat est améliorée. L'augmentation de la salinité réduit la qualité du filtrat. Des essais de micro et ultrafiltration des mêmes effluents ont montré que seule la NF permet d'atteindre un niveau de rétention important des siloxanes. Des essais de nanofiltration tangentielle ont ensuite été réalisés afin de préparer une étude plus complète nécessaire en vue d'une éventuelle l'industrialisation du procédé. La biodégradabilité des siloxanes a été explorée par la méthode Oxitop. Aucune activité biologique provoquée par les siloxanes n'a été enregistrée lors de tests Oxitop réalisés avec des boues activées de stations d'épuration, mais aucun effets toxique ou inhibiteur n'ont été observés non plus. Un bioréacteur à membrane pilote a été alimenté pendant 5 mois au laboratoire avec une solution contenant des siloxanes pour tenter d'acclimater les boues activées aux siloxanes. Les tests Oxitop effectués avec des boues issues du pilote n'ont pas mis en évidence d'acclimatation des micro-organismes aux siloxanes. / Industrial production of silicones generates liquid streams containing siloxanes with high salinity. In a perspective of sustainable development and to consider the growing concern about the environmental impact of industrial residues, we are looking for treatment processes to remove siloxanes in wastewater. This study aims to evaluate the performance of two processes for the treatment of effluents containing siloxanes: nanofiltration and biological oxidation, Frontal nanofiltration experiments were carried out. Firstly, experiments with synthetic solutions (mix of water and siloxanes) have shown almost total siloxane retention in all conditions investigated. Then, experiments were performed with effluents of different compositions representative of industrial ones in order to evaluate the process robustness. It was concluded that nanofiltration is efficient to reduce the total organic content of the effluent and significantly reduces siloxanes concentration. Dilution of the effluent causes a decrease in TOC reduction and siloxanes retention, but the permeate quality is improved. Increasing salinity reduces the filtrate quality. Micro and ultrafiltration of identical effluents confirmed that only NF can reach a high level of siloxane retention. Tangential nanofiltration experiences were performed in order to prepare a more complete study which is necessary to anticipate industrialization of the process. Siloxanes biodegradability was explored by Oxitop method. No biological activity induced by siloxanes was recorded in Oxitop tests with activated sludge from wastewater treatment plant, but no toxic or inhibitory effects were observed. A pilot membrane bioreactor was fed in the laboratory for 6 months with a solution containing siloxanes to try to acclimate activated sludge to siloxane. Oxitop tests performed with sludge taken from the pilot did not show acclimation of microorganisms to siloxanes.
4

Nouveaux procédés de bioremédiation pour le traitement des sols et des sédiments sélénifères / Novel bioremediation processes for treatment of seleniferous soils and sediment

Wadgaonkar, Shrutika 18 December 2017 (has links)
L'objectif de cette thèse a été de développer une technologie pour l'assainissement des sols / sédiments sélénifères et d’étudier la réduction microbienne des oxy-anions de sélénium dans différentes conditions de respiration et de configurations du bioréacteur.Le sol sélénifère prélevé, dans les terres agricoles cultivées de blé au Pendjab (Inde), a été caractérisé et son lavage a été optimisé en faisant varier les paramètres tels que le temps de réaction, la température, le pH et le rapport liquide / solide. Afin de maximiser l'élimination et la récupération du sélénium à partir de ce sol, l'effet des ions compétiteurs et les composés oxydants comme les agents d'extraction pour le lavage du sol, ont également été étudiés. Bien que les agents oxydants aient montré une efficacité maximale d'élimination du sélénium (39%), la présence d'agents oxydants dans le lixiviat et le sol agricole peut augmenter le coût de leur post-traitement. Les plantes aquatiques, Lemma minor et Egeria densa ont été utilisées pour étudier la phyto-remédiation du lixiviat du sol contenant des agents oxydants. Cependant, l'efficacité d'élimination du sélénium par les plantes aquatiques a été significativement affectée par les fortes concentrations de ces agents oxydants dans le lixiviat du sol.Le rinçage du sol sélénifère a révélé un motif de migration du sélénium à travers la colonne du sol. La migration de la fraction de sélénium soluble de la couche supérieure vers la couche inférieure et sa réduction et son accumulation subséquentes dans les couches inférieures de la colonne de sol, ont été observées pendant le rinçage du sol. L'efficacité d'élimination du sélénium par la méthode de rinçage du sol a diminué avec une augmentation de la hauteur de la colonne. De plus, le lixiviat contenant des oxy-anions de sélénium obtenus à partir du lavage du sol, a été traité dans un réacteur UASB en faisant varier l'alimentation organique. Des effluents contenant moins de 5 μg de sélénium L-1 ont été obtenus, ce qui est conforme aux normes de l'USEPA pour la limite de rejet de sélénium dans les eaux usées.De plus, la bio-remédiation ex situ des oxy-anions de sélénium a été étudiée dans des conditions variables. Une bactérie aérobie (Delftia lacustris) capable de transformer le sélénate et le sélénite en sélénium élémentaire, mais aussi en composés d'ester de sélénium solubles jusque-là inconnus, a été isolée et caractérisée de manière fortuite. Alternativement, la bio-réduction anaérobie du sélénate couplé au méthane en tant que donneur d'électrons, a été étudiée dans des bouteilles de sérum et un filtre percolateur en utilisant des sédiments marins comme inoculum. Enfin, l'effet de la contamination d'autres oxy-anions chalcogènes, en plus du sélénium, a été étudié. La réduction simultanée de la sélénite et de la tellurite par un consortium microbien mixte ainsi que la rétention des nanostructures de Se et de Te biogènes dans l'EPS, ont été réalisées durant une opération de 120 jours dans un bioréacteur UASB / The aim of this Ph.D. was to develop a technology for the remediation of seleniferous soils/sediments and to explore microbial reduction of selenium oxyanions under different respiration conditions and bioreactor configurations.Seleniferous soil collected from the wheat-grown agricultural land in Punjab (India) was characterized and its soil washing was optimized by varying parameters such as reaction time, temperature, pH and liquid to solid ratio. In order to maximize selenium removal and recovery from this soil, effect of competing ions and oxidizing agents as chemical extractants for soil washing were also studied. Although oxidizing agents showed a maximum selenium removal efficiency (39%), the presence of oxidizing agents in the leachate and the agricultural soil may increase the cost of their post-treatment. Aquatic plants, Lemma minor and Egeria densa were used to study phytoremediation of the soil leachate containing oxidizing agents. However, the selenium removal efficiency by aquatic weeds was significantly affected by the high concentrations of these oxidizing agents in the soil leachate.Seleniferous soil flushing revealed the selenium migration pattern across the soil column. Migration of soluble selenium fraction from the upper to the lower layers and its subsequent reduction and accumulation in the lower layers of the soil column was observed during soil flushing. The selenium removal efficiency by the soil flushing method decreased with an increase in the column height. Furthermore, the soil leachate containing selenium oxyanions obtained from soil washing was treated in a UASB reactor by varying the organic feed. Effluent containing less than 5 μg L-1 selenium was achieved, which is in accordance with the USEPA guidelines for selenium wastewater discharge limit.Moreover, ex situ bioremediation of selenium oxyanions was studied under variable conditions. An aerobic bacterium (Delftia lacustris) capable of transforming selenate and selenite to elemental selenium, but also to hitherto unknown soluble selenium ester compounds was serendipitously isolated and characterized. Alternatively, anaerobic bioreduction of selenate coupled to methane as electron donor was investigated in serum bottles and a biotrickling filter using marine sediment as inoculum. Finally, the effect of contamination of other chalcogen oxyanions in addition to selenium was studied. Simultaneous reduction of selenite and tellurite by a mixed microbial consortium along with the retention of biogenic Se and Te nanostructures in the EPS was achieved during a 120-day UASB bioreactor operation
5

Avaliação das condições do tratamento biológico de hidrolisados hemicelulósicos visando melhorar a produção de etanol por Scheffersomyces (Pichia) stipitis / Evaluation of biological treatment conditions of hemicellulosic hydrolysates aiming to improve ethanol production by Scheffersomyces (Pichia) stipitis

Fonseca, Bruno Guedes 14 March 2014 (has links)
O presente estudo teve como principal objetivo avaliar a capacidade de Saccharomyces cerevisiae em metabolizar os compostos tóxicos presentes em hidrolisados hemicelulósicos de palha de arroz (HHPA) e de poda de oliveira (HHPO), visando a obtenção de hidrolisados com menor grau de toxicidade para Pichia stipitis. Após determinada a composição dos hidrolisados (açúcares e compostos tóxicos) foi avaliado o nível de concentração do HHPA capaz de inibir o metabolismo de P. stipitis. Em seguida, foi avaliado o efeito do tempo, concentração de S. cerevisiae, pH e aeração sobre a composição destes hidrolisados, tendo como resposta a fermentabilidade de P. stipitis. Nas condições otimizadas do biotratamento, as fermentações de P. stipitis foram conduzidas em frascos agitados e em biorreator, e as respostas avaliadas foram o consumo de D-xilose, fator de conversão de substrato em etanol (YP/S) e produtividade volumétrica em etanol (QP). Os ensaios de biotransformação destes hidrolisados, assim como do meio sintético (MS), o qual mimetizou o teor de açúcares e compostos tóxicos presentes no HHPA, mostraram que as modificações na composição destes meios foram dependentes do tempo de tratamento. Durante o tratamento, a levedura S. cerevisiae foi capaz de consumir apenas a D-glicose com baixas produções de etanol glicerol e ácido acético. Além disso, no HHPA e MS o 5-HMF e furfural foram quase que totalmente assimilados (> 90%), com formação de baixos teores de ácido furóico. Nestes meios, S. cerevisiae converteu parcialmente os ácidos ferúlico (15%) e p-cumárico (20%), sendo observado apenas produto de conversão do ácido ferúlico (álcool vanilil). A vanilina foi completamente assimilada em MS, porém, em HHPA foi constatado um residual do composto (42%), sendo o álcool vanilil o principal produto de conversão. Em relação ao HHPO foi observada assimilação de 47% de furanos totais e 11% de fenólicos totais, não sendo identificados produtos de conversão. Os resultados da fermentação de P. stipitis em HHPA mostraram que o tratamento biológico por 6 horas favoreceu o consumo de D-xilose e a produção de etanol, indicando que este parâmetro é um importante fator a ser considerado. Nestas condições, o consumo de D-xilose foi de 57% com produção de 9 g/L de etanol (YP/S = 0,18 g/g e QP = 0,086 g/L.h). Os resultados da fermentação do HHPO apresentaram valores inferiores de YP/S (0,14 g/g) e QP (0,060 g/L.h) quando comparados ao HHPA, o que indica um maior grau de toxicidade deste hidrolisado. Em relação ao MS, verificou-se que o biotratamento favoreceu em aproximadamente 40% o consumo de D-xilose e a produção de etanol por P. stipitis, quando comparado com o MS não-tratado. As melhores condições de concentração de S. cerevisiae (5 g/L), pH (3,0) e fator de aeração (6,5) definidas no HHPA através de um planejamento experimental, proporcionou um consumo de 67% de D-xilose por P. stipitis, com produção de 13,5 g/L de etanol (YP/S = 0,24 g/g e QP = 0,15 g/L.h). Na fermentação em biorreator, P. stipitis foi capaz de consumir totalmente a D-xilose, produzindo 23 g/L de etanol, após 44 horas. Com base nestes resultados, pode-se concluir que o tratamento dos hidrolisado hemicelulósicos com S. cerevisiae é uma técnica promissora capaz de diminuir o grau de toxicidade destes meios com consequente melhoria em sua fermentabilidade, especialmente na velocidade de produção de etanol. / The aim of this work was to study the ability of Saccharomyces cerevisiae to metabolize a variety of toxic compounds found in rice straw (RSHH) and olive tree pruning (OTHH) hemicellulosic hydrolysates, in order to obtain hydrolysates with lower toxicity for Pichia stipitis. After determined the hydrolysate composition (sugar and toxic compounds) was evaluated the RSHH concentration level able to inhibit the P. stipitis metabolism. Then, the effect of time, S. cerevisiae concentration, pH and aeration on the hydrolysates composition was evaluated, and the fermentation was used as response. Under optimized conditions of biotreatment, P. stipitis fermentations were conducted in shake flasks and in bioreactor. In relation to the biotransformation assays of these hydrolysates, as well as synthetic medium (SM), with the same sugar and toxic compounds concentrations found in RSHH, the results showed that changes in the media compositions were dependent on the treatment time. During the treatment, S. cerevisiae consumed only D-glucose with low ethanol, glycerol, and acetic acid production. Furthermore, in SM and RSHH media, 5-HMF and furfural were almost completely assimilated (> 90 %), with low levels of furoic acid formation. In these media, S. cerevisiae partially converted ferulic acid (15%) and p-coumaric acid (20%), being observed only the conversion product of ferulic acid (vanillyl alcohol). Vanillin was totally assimilated in SM, however a residual of this compound (42%) was observed in RSHH, being vanillyl alcohol the main conversion product. Regarding OTHH was observed the assimilation of total furans (47%) and total phenolic (11%), and no conversion products were identified. The results from the P. stipitis fermentation in RSHH showed that biotreatment for 6 hours favored D-xylose consumption and ethanol production, indicating that this parameter is an important factor to be considered. In these conditions, D-xylose consumption was 57% with 9 g/L ethanol production (YP/S = 0.18 g/g QP = 0.086 g/Lh). The results of OTHH fermentation showed lower YP/S (0.14 g/g) and QP (0.060 g/L.h ) compared to RSHH, which indicates a higher degree of toxicity in OTHH. Regarding SM, the biotreatment increased D-xylose consumption and ethanol production by P. stipitis in approximately 40%, when compared with untreated-SM. The most suitable conditions of S. cerevisiae concentration (5 g/ L), pH (3.0) and the aeration factor (6.5) defined in RSHH through an experimental design, provided 67% of D-xylose consumption, and 13.5 g/L ethanol production by P. stipitis (YP/S = 0.24 g/g QP = 0.15 g/L.h). In bioreactor, P. stipitis was able to completely consume D-xylose, producing 23 g/L ethanol after 44 hours. Based on these results, it can be concluded that previous treatment of hemicellulose hydrolysates with S. cerevisiae is a promising technique capable of reducing the toxicity degree of RSHH and OTHH, with consequent improvement in their fermentability, especially on ethanol production rate.
6

Avaliação das condições do tratamento biológico de hidrolisados hemicelulósicos visando melhorar a produção de etanol por Scheffersomyces (Pichia) stipitis / Evaluation of biological treatment conditions of hemicellulosic hydrolysates aiming to improve ethanol production by Scheffersomyces (Pichia) stipitis

Bruno Guedes Fonseca 14 March 2014 (has links)
O presente estudo teve como principal objetivo avaliar a capacidade de Saccharomyces cerevisiae em metabolizar os compostos tóxicos presentes em hidrolisados hemicelulósicos de palha de arroz (HHPA) e de poda de oliveira (HHPO), visando a obtenção de hidrolisados com menor grau de toxicidade para Pichia stipitis. Após determinada a composição dos hidrolisados (açúcares e compostos tóxicos) foi avaliado o nível de concentração do HHPA capaz de inibir o metabolismo de P. stipitis. Em seguida, foi avaliado o efeito do tempo, concentração de S. cerevisiae, pH e aeração sobre a composição destes hidrolisados, tendo como resposta a fermentabilidade de P. stipitis. Nas condições otimizadas do biotratamento, as fermentações de P. stipitis foram conduzidas em frascos agitados e em biorreator, e as respostas avaliadas foram o consumo de D-xilose, fator de conversão de substrato em etanol (YP/S) e produtividade volumétrica em etanol (QP). Os ensaios de biotransformação destes hidrolisados, assim como do meio sintético (MS), o qual mimetizou o teor de açúcares e compostos tóxicos presentes no HHPA, mostraram que as modificações na composição destes meios foram dependentes do tempo de tratamento. Durante o tratamento, a levedura S. cerevisiae foi capaz de consumir apenas a D-glicose com baixas produções de etanol glicerol e ácido acético. Além disso, no HHPA e MS o 5-HMF e furfural foram quase que totalmente assimilados (> 90%), com formação de baixos teores de ácido furóico. Nestes meios, S. cerevisiae converteu parcialmente os ácidos ferúlico (15%) e p-cumárico (20%), sendo observado apenas produto de conversão do ácido ferúlico (álcool vanilil). A vanilina foi completamente assimilada em MS, porém, em HHPA foi constatado um residual do composto (42%), sendo o álcool vanilil o principal produto de conversão. Em relação ao HHPO foi observada assimilação de 47% de furanos totais e 11% de fenólicos totais, não sendo identificados produtos de conversão. Os resultados da fermentação de P. stipitis em HHPA mostraram que o tratamento biológico por 6 horas favoreceu o consumo de D-xilose e a produção de etanol, indicando que este parâmetro é um importante fator a ser considerado. Nestas condições, o consumo de D-xilose foi de 57% com produção de 9 g/L de etanol (YP/S = 0,18 g/g e QP = 0,086 g/L.h). Os resultados da fermentação do HHPO apresentaram valores inferiores de YP/S (0,14 g/g) e QP (0,060 g/L.h) quando comparados ao HHPA, o que indica um maior grau de toxicidade deste hidrolisado. Em relação ao MS, verificou-se que o biotratamento favoreceu em aproximadamente 40% o consumo de D-xilose e a produção de etanol por P. stipitis, quando comparado com o MS não-tratado. As melhores condições de concentração de S. cerevisiae (5 g/L), pH (3,0) e fator de aeração (6,5) definidas no HHPA através de um planejamento experimental, proporcionou um consumo de 67% de D-xilose por P. stipitis, com produção de 13,5 g/L de etanol (YP/S = 0,24 g/g e QP = 0,15 g/L.h). Na fermentação em biorreator, P. stipitis foi capaz de consumir totalmente a D-xilose, produzindo 23 g/L de etanol, após 44 horas. Com base nestes resultados, pode-se concluir que o tratamento dos hidrolisado hemicelulósicos com S. cerevisiae é uma técnica promissora capaz de diminuir o grau de toxicidade destes meios com consequente melhoria em sua fermentabilidade, especialmente na velocidade de produção de etanol. / The aim of this work was to study the ability of Saccharomyces cerevisiae to metabolize a variety of toxic compounds found in rice straw (RSHH) and olive tree pruning (OTHH) hemicellulosic hydrolysates, in order to obtain hydrolysates with lower toxicity for Pichia stipitis. After determined the hydrolysate composition (sugar and toxic compounds) was evaluated the RSHH concentration level able to inhibit the P. stipitis metabolism. Then, the effect of time, S. cerevisiae concentration, pH and aeration on the hydrolysates composition was evaluated, and the fermentation was used as response. Under optimized conditions of biotreatment, P. stipitis fermentations were conducted in shake flasks and in bioreactor. In relation to the biotransformation assays of these hydrolysates, as well as synthetic medium (SM), with the same sugar and toxic compounds concentrations found in RSHH, the results showed that changes in the media compositions were dependent on the treatment time. During the treatment, S. cerevisiae consumed only D-glucose with low ethanol, glycerol, and acetic acid production. Furthermore, in SM and RSHH media, 5-HMF and furfural were almost completely assimilated (> 90 %), with low levels of furoic acid formation. In these media, S. cerevisiae partially converted ferulic acid (15%) and p-coumaric acid (20%), being observed only the conversion product of ferulic acid (vanillyl alcohol). Vanillin was totally assimilated in SM, however a residual of this compound (42%) was observed in RSHH, being vanillyl alcohol the main conversion product. Regarding OTHH was observed the assimilation of total furans (47%) and total phenolic (11%), and no conversion products were identified. The results from the P. stipitis fermentation in RSHH showed that biotreatment for 6 hours favored D-xylose consumption and ethanol production, indicating that this parameter is an important factor to be considered. In these conditions, D-xylose consumption was 57% with 9 g/L ethanol production (YP/S = 0.18 g/g QP = 0.086 g/Lh). The results of OTHH fermentation showed lower YP/S (0.14 g/g) and QP (0.060 g/L.h ) compared to RSHH, which indicates a higher degree of toxicity in OTHH. Regarding SM, the biotreatment increased D-xylose consumption and ethanol production by P. stipitis in approximately 40%, when compared with untreated-SM. The most suitable conditions of S. cerevisiae concentration (5 g/ L), pH (3.0) and the aeration factor (6.5) defined in RSHH through an experimental design, provided 67% of D-xylose consumption, and 13.5 g/L ethanol production by P. stipitis (YP/S = 0.24 g/g QP = 0.15 g/L.h). In bioreactor, P. stipitis was able to completely consume D-xylose, producing 23 g/L ethanol after 44 hours. Based on these results, it can be concluded that previous treatment of hemicellulose hydrolysates with S. cerevisiae is a promising technique capable of reducing the toxicity degree of RSHH and OTHH, with consequent improvement in their fermentability, especially on ethanol production rate.
7

Biofiltração de compostos orgânicos voláteis e gás sulfídrico em estações de despejos industriais de processamento de hidrocarbonetos. / Biofiltration of volatile organic compounds and hydrogen sulphide in an wastewater treatment plant of processing oil.

Beatrix Nery Villa Martignoni 09 March 2007 (has links)
Neste trabalho foi estudado o tratamento simultâneo por biofiltração de emissões de compostos orgânicos voláteis, COV e gás sulfídrico, H2S, em estações de tratamento de despejos industriais, de refinaria de petróleo, ETDI. A biofiltração dos gases emanados da EDTI mostrou ser uma técnica de alta eficiência, atingindo valores de 95 a 99 % para tratamento simultâneo de COV e H2S em concentrações de 1000 e 100 ppmv, respectivamente. Foram realizados testes em 95 dias consecutivos de operação, em uma planta piloto instalada na Superintendência da Industrialização do Xisto, SIX, em São Mateus do Sul, Paraná, de março a agosto de 2006. O biofiltro foi do tipo fluxo ascendente, com 3,77 m3 de leito orgânico, composto de turfa, carvão ativado, lascas de madeira, serragem brita fina além de outros componentes menores. Foi realizada inoculação biológica com lodo filtrado de estação de tratamento de esgoto sanitário. As vazões de gás aplicadas variaram de 85 a 407 m3/h, resultando em taxas de carga de massa de 11,86 a 193,03 g de COV/h.m3 de leito e tempos de residência de 24 segundos a 6,5 minutos, com tempo ótimo de 1,6 minutos. A capacidade máxima de remoção do sistema encontrada, nas condições testadas, foi de 15 g de COV/h. m3, compatível com os valores encontrados na literatura para depuração biológica de COV na escala praticada. Também foi verificada a redução de componentes específicos de BTX, demonstrando boa degradabilidade dos compostos orgânicos. Finalmente o biofiltro demonstrou boa robustez biológica diante dos desvios operacionais intencionalmente provocados, tais como falta de umidade do leito, baixa temperatura, alta vazão, falta de carga de COV e baixo pH do leito. Depois de retomada a condição de operação estável, a biofiltração rapidamente atingiu o estado de equilíbrio, assegurando o uso eficiente e confiável da técnica no tratamento de gases de EDTI na indústria do hidrocarbonetos ou em refinarias de petróleo. / In this project the biofiltration technique was applied as air pollution control technology to treat simultaneously emissions containing volatile organic compounds, VOC and hydrogen sulfide, H2S, in hydrocarbon processing industries and oil refinery Waste Water Treatment Plant, WWTP. The technique demonstrated high biological efficiency up to 95 and 100 % of simultaneous biofiltration of VOC and H2S, with inicial concentration of 1000 and 100 ppmv, respectively. Tests were conducted at UN-SIX/ Petrobras Oil Shale Processing Unit facilities through 95 consecutives days, from March to August 2006. The chosen reactor model was an up stream system, pilot plant scale with volume of 3.77 m3 of an organic compost media made out a blend of peat, rotten wood chips, activated carbon, lime, among other minor components. The biological inoculation was done with sanitary sludge from WWTP. The pilot plant capacity was able to treat from 85 to 480 m3/h of WWTP off-gas, resulting COV application rate from 11.86 to 193.03 g VOC/ h. m3 of media, and residence time from 24 sec to 6.5 minutes, with optimum value at 1.6 minutes. The system maximum elimination rate was about 15 g VOC/h. m3, value comparable to ones presented in open literature. The specific BTX compounds depuration was observed, demonstrating relevant media specificity to treat organic compounds. Finally the biofiltration systems demonstrated good biological toughness considering the operational provoked upsets, as lack of media bed humidity, low biofiltration temperature, high flow rate, lack of VOC flow and acid pH. After normal operational conditions were retaken all process characteristics and efficiency [was] reached the correspondent values, showing reliable and efficient use of the technique to treat off gases in WWTP of hydrocarbon processing industries and Oil Refineries.
8

Biofiltração de compostos orgânicos voláteis e gás sulfídrico em estações de despejos industriais de processamento de hidrocarbonetos. / Biofiltration of volatile organic compounds and hydrogen sulphide in an wastewater treatment plant of processing oil.

Beatrix Nery Villa Martignoni 09 March 2007 (has links)
Neste trabalho foi estudado o tratamento simultâneo por biofiltração de emissões de compostos orgânicos voláteis, COV e gás sulfídrico, H2S, em estações de tratamento de despejos industriais, de refinaria de petróleo, ETDI. A biofiltração dos gases emanados da EDTI mostrou ser uma técnica de alta eficiência, atingindo valores de 95 a 99 % para tratamento simultâneo de COV e H2S em concentrações de 1000 e 100 ppmv, respectivamente. Foram realizados testes em 95 dias consecutivos de operação, em uma planta piloto instalada na Superintendência da Industrialização do Xisto, SIX, em São Mateus do Sul, Paraná, de março a agosto de 2006. O biofiltro foi do tipo fluxo ascendente, com 3,77 m3 de leito orgânico, composto de turfa, carvão ativado, lascas de madeira, serragem brita fina além de outros componentes menores. Foi realizada inoculação biológica com lodo filtrado de estação de tratamento de esgoto sanitário. As vazões de gás aplicadas variaram de 85 a 407 m3/h, resultando em taxas de carga de massa de 11,86 a 193,03 g de COV/h.m3 de leito e tempos de residência de 24 segundos a 6,5 minutos, com tempo ótimo de 1,6 minutos. A capacidade máxima de remoção do sistema encontrada, nas condições testadas, foi de 15 g de COV/h. m3, compatível com os valores encontrados na literatura para depuração biológica de COV na escala praticada. Também foi verificada a redução de componentes específicos de BTX, demonstrando boa degradabilidade dos compostos orgânicos. Finalmente o biofiltro demonstrou boa robustez biológica diante dos desvios operacionais intencionalmente provocados, tais como falta de umidade do leito, baixa temperatura, alta vazão, falta de carga de COV e baixo pH do leito. Depois de retomada a condição de operação estável, a biofiltração rapidamente atingiu o estado de equilíbrio, assegurando o uso eficiente e confiável da técnica no tratamento de gases de EDTI na indústria do hidrocarbonetos ou em refinarias de petróleo. / In this project the biofiltration technique was applied as air pollution control technology to treat simultaneously emissions containing volatile organic compounds, VOC and hydrogen sulfide, H2S, in hydrocarbon processing industries and oil refinery Waste Water Treatment Plant, WWTP. The technique demonstrated high biological efficiency up to 95 and 100 % of simultaneous biofiltration of VOC and H2S, with inicial concentration of 1000 and 100 ppmv, respectively. Tests were conducted at UN-SIX/ Petrobras Oil Shale Processing Unit facilities through 95 consecutives days, from March to August 2006. The chosen reactor model was an up stream system, pilot plant scale with volume of 3.77 m3 of an organic compost media made out a blend of peat, rotten wood chips, activated carbon, lime, among other minor components. The biological inoculation was done with sanitary sludge from WWTP. The pilot plant capacity was able to treat from 85 to 480 m3/h of WWTP off-gas, resulting COV application rate from 11.86 to 193.03 g VOC/ h. m3 of media, and residence time from 24 sec to 6.5 minutes, with optimum value at 1.6 minutes. The system maximum elimination rate was about 15 g VOC/h. m3, value comparable to ones presented in open literature. The specific BTX compounds depuration was observed, demonstrating relevant media specificity to treat organic compounds. Finally the biofiltration systems demonstrated good biological toughness considering the operational provoked upsets, as lack of media bed humidity, low biofiltration temperature, high flow rate, lack of VOC flow and acid pH. After normal operational conditions were retaken all process characteristics and efficiency [was] reached the correspondent values, showing reliable and efficient use of the technique to treat off gases in WWTP of hydrocarbon processing industries and Oil Refineries.
9

Wastewater Reuse: Comprehensive Study about Treatment System Efficiency and Potential Public Health Concerns

Park, Eunyoung January 2015 (has links)
No description available.
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Evaluation Of Biosorption Activated Media Under Roadside Swales For Stormwater Quality Improvement And Harvesting

Hood, Andrew Charles 01 January 2012 (has links)
Stormwater runoff from highways is a source of pollution to surface water bodies and groundwater. This project develops a bio-detention treatment and harvesting system that is incorporated into roadside swales. The bio-detention system uses Bold & Gold™, a type of biosorption activated media (BAM), to remove nutrients from simulated highway runoff and then store the water in underground vaults for infiltration, controlled discharge, and/or irrigation and other non-potable applications. In order to design a bio-detention system, media characteristics and media/water quality relationships are required. Media characteristics determined through testing include: specific gravity, permeability, infiltration, maximum dry density, moisture content of maximum dry density, and particle-size distribution. One of the goals of this experiment is to compare the nitrogen and phosphorous species concentrations in the effluent of BAM to sandy soil for simulated highway runoff. Field scale experiments are done on an elevated test bed that simulates a typical roadway with a swale. The swale portion of the test bed is split into halves using BAM and sandy soil. The simulated stormwater flows over a concrete section, which simulates a roadway, and then over either sod covered sandy soil or BAM. One, one and a half, and three inch storms are each simulated three times with a duration of 30 minutes each. During the simulated storm event, initial samples of the runoff (influent) are taken. The test bed is allowed to drain for two hours after the rainfall event and then samples of each of the net effluents are taken. In addition to the field scale water quality testing, column tests are also preformed on the sandy soil and Bold & Gold™ without sod present. Sod farms typically use fertilizer to increase production, thus it is reasonable to assume that the sod will leach nutrients into the soils on the iv test bed, especially during the initial test runs. The purpose of the column tests is to obtain a general idea of what percentage removals of total phosphorus and total nitrogen are obtained by the sandy soil and Bold & Gold™. It is shown that the Bold & Gold™ media effluent has significantly lower concentrations of total nitrogen and total phosphorus compared to the effluent of the sandy soil based on an 80% confidence level. The Bold & Gold™ has a 41% lower average effluent concentration of total nitrogen than the sandy soil. The Bold & Gold™ media has a 78% lower average effluent concentration of total phosphorus than the sandy soil. Using both the column test data in combination with the field scale data, it is determined that the Bold & Gold™ BAM system has a total phosphorus removal efficiency of 71%. The removal efficiency is increased when stormwater harvesting is considered. A total phosphorus reduction of 94% is achieved in the bio-detention & harvesting swale system sample design problem

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