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Evaluation of the Removal Efficiency of Per- and Polyfluoroalkyl Substances in Drinking Water using Nanofiltration Membranes, Active Carbon and Anion Exchange / Utvärdering av reningseffektiviteten av per- och polyfluorerade alkylsubstanser i dricksvatten med nanofiltrering, aktivt kol och jonbytarmassaLindegren, Klara January 2015 (has links)
Per- and polyfluoroalkyl substances (PFASs) is a group of man-made, highly persistent chemicals. Due to the specific surface-active attributes of these molecules, applications are numerous and feed an economically important industry. During the last decade, PFASs have been detected globally in the environment, living organisms and tap water. The combination of toxic properties and high bioaccumulative potential, together with the discovery that conventional water treatment methods do not remove PFAS, renders further research on purification methods highly needed. Three techniques of purifying water from PFASs were examined. Nanofiltration technology (NF) is a membrane filtration technique, which produces a purified product (the permeate) by generating an effluent of high contaminant concentration (the reject water). To decontaminate the reject water, adsorption by granular activated carbon (GAC) or anion exchange (AE) have been proposed. The efficiency of these three technologies was studied at Bäcklösa drinking water treatment plant (DWTP) in Uppsala. A nanofiltration pilot with two 270NF membranes (Dow Filmtech™), connected in series, was used. A high removal efficiency (>90%) was found for all PFASs. Furthermore, it was confirmed that the concentration in the permeate water was a function of the concentration in the incoming raw water; increased PFAS raw water concentration resulted in increased PFAS permeate concentration. Size-exclusion and electrostatic repulsion were deemed important mechanisms. For the comparison of GAC (Filtrasorb 400®) and AE (Purolite® A-600), a column experiment was set up. The perfluoroalkane (-alkyl) sulfonic acids (PFSAs) and perfluorooctanesulfonamide (FOSA) had similar removal efficiencies using both GAC and AE, and the efficiency increased with increasing chain length. AE was found to have a higher average removal efficiency of perfluoroalkyl carboxylic acid (PFCAs) (62-95%) than GAC (49-81%). In conclusion, longer chain length PFASs were removed more effectively than shorter-chained, and the PFSAs and FOSA showed higher removal efficiency compared to the PFCAs. Furthermore, linear isomers were removed more effectively than branched for GAC and AE. In contrast, the opposite was found for the NF membrane, where branched isomers were better retained. / Per- och polyfluorerade alkylsubstanser (PFAS) är en grupp syntetiska, ytterst persistenta kemikalier. På grund av deras ytaktiva egenskaper är de lämpliga för användning i många produkter och tillverkningsprocesser, och är således viktiga för en ekonomiskt betydande industri. Under det senaste årtiondet har PFAS påträffats i miljön, levande organismer och kranvatten världen över. Kombinationen av toxiska egenskaper, en hög bioackumuleringspotential och upptäckten att konventionella reningsmetoder inte avlägsnar substanserna från vatten, gör att vidare forskning av reningsmetoder för PFAS är mycket angelägen. Tre reningsteknikers förmåga att rena vatten från PFAS undersöktes. Nanofiltrering (NF) är en membranfiltreringsteknik som utöver den renade produkten, permeatet, även framställer en biprodukt av hög föroreningsgrad, rententatet. För att rena rententatet har adsorption till granulärt aktivt kol (GAC) eller jonbytarmassa (AE) föreslagits. Teknikerna utvärderades på Bäcklösa Vattenverk i Uppsala. Nanofiltreringen undersöktes i en pilotanläggning där två 270NF (Dow Filmtech™) membran var seriekopplade. En hög reningsgrad (>90%) konstaterades för alla typer av PFAS. Vidare visades PFAS-koncentrationen i permeatet vara en funktion av PFAS-koncentrationen i råvattnet; en ökad råvattenkoncentration gav en ökad permeatkoncentration. Storleksseparation och elektrostatisk repulsion befanns vara viktiga mekanismer som påverkade reningsgraden. För att undersöka de mekanismer som påverkar PFAS-adsorption jämfördes GAC (Filtrasorb 400®) och AE (Purolite® A-600) i ett kolonnexperiment. Reningsgraden för GAC och AE av perfluorerade sulfonsyror (PFSA) och perfluorooktan sulfonamider (FOSA) var lika hög och reningseffektiviteten ökade med ökande kolkedjelängd. AE återfanns ha en högre genomsnittlig reningsgrad av perfluorkarboxylsyror (PFCA) (62-95%) än GAC (49-81%). Sammanfattningsvis avlägsnades PFAS av längre kolkedjelängd mer effektivt än kortare kolkedjor, och PFAS med sulfonsyror och sulfonamider som funktionella grupper uppvisade en högre reningsgrad än karboxylsyrorna. Vidare renades linjära isomerer mer effektivt än grenade både genom GAC och AE. Däremot konstaterades det motsatta för NF-membranen, där grenade isomerer renades mer effektivt. / SafeDrink
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Remoção dos fármacos atenolol, paracetamol e ampicilina por adsorção em carvão ativadoHaro, Nathalia Krummenauer January 2017 (has links)
Os fármacos são essenciais para a preservação da saúde do homem e de animais e também na prevenção de doenças. Entretanto, seu alto consumo associado ao descarte incorreto e aos tratamentos ineficientes de águas e efluentes podem trazer grandes prejuízos ao meio ambiente como, por exemplo, a resistência bacteriana. O objetivo deste trabalho foi estudar a remoção de ampicilina (AMP), atenolol (ATN) e paracetamol (PAR), fármacos de três classes distintas, em soluções aquosas através da técnica de adsorção em carvão ativado granular (CAG). Foram realizados experimentos de adsorção em batelada avaliando o efeito dos parâmetros pH, tempo de contato e concentração de sólido adsorvente. O comportamento cinético da adsorção dos fármacos em carvão ativado granular foi avaliado por meio dos modelos de pseudo-primeira ordem, pseudosegunda ordem e difusão intrapartícula. Ainda, isotermas de equilíbrio para estes sistemas foram construídas em diferentes temperaturas (15, 25 e 35 °C) e analisadas através dos modelos de Langmuir, Freundlich e Sips. O processo de adsorção também foi avaliado através de ensaios termodinâmicos. A adsorção em coluna de leito fixo foi avaliada utilizando planejamentos experimentais para os fármacos e os efeitos da massa do leito de adsorvente (0,5 – 1,5 g) e da vazão de alimentação (10 – 15 mL min-1) foram estudados Ainda, a fim de se avaliar o comportamento dos fármacos quando em mistura, foram realizados ensaios de adsorção em batelada e em coluna de leito fixo da mistura de ampicilina e paracetamol. Os melhores resultados encontrados nos ensaios de adsorção batelada foram: pH 6 e concentração de sólido adsorvente de 10 g L-1 para os três fármacos. O tempo de adsorção mais adequado foi de 90 minutos para o ATN e 120 min para AMP e PAR. Nessas condições foi possível obter remoções de 90 %, 94 % e 96 % para a ampicilina, atenolol e paracetamol, respectivamente. O modelo cinético que melhor descreveu o processo de adsorção foi o de pseudo-primeira ordem, para os fármacos ampicilina e paracetamol, e pseudo-segunda ordem para o atenolol. As isotermas obtidas para os fármacos indicaram que o processo de adsorção é de natureza endotérmica, ou seja, a adsorção é favorecida com o aumento da temperatura. Para a AMP, o melhor ajuste das isotermas foi obtido pelo modelo de Langmuir nas temperaturas de 15 ºC e 25 ºC e pelo modelo de Sips na temperatura de 35 ºC. Para o ATN, o melhor ajuste foi obtido pelo modelo de Freundlich e, para o PAR, o modelo de Sips, nas três temperaturas estudadas. Os ensaios termodinâmicos indicaram que o processo de adsorção dos fármacos é favorável e espontâneo e comprovou a natureza endotérmica do processo Em relação aos resultados obtidos na adsorção em coluna de leito fixo foi observado que os tempos de ruptura e de saturação aumentam com o aumento da massa de sólido presente no leito e diminuem com o aumento da vazão. A massa de adsorvente apresentou efeito negativo sobre a fração de leito utilizado e foi significativa no processo de adsorção dos três fármacos. Já a vazão de alimentação só foi significativa na adsorção em leito fixo da AMP e apresentou efeito positivo na fração de leito utilizado. Os maiores volumes de efluente tratado foram obtidos com a maior massa de sólido utilizada (1,5 g) e com a menor vazão de alimentação testada (10 mL min-1). Na adsorção multicomponente em batelada, verificou-se que há concorrência entre os fármacos pelos sítios ativos do CAG disponíveis para adsorção. Os resultados obtidos nos ensaios das isotermas de adsorção mostraram que o comportamento dos fármacos em mistura é o mesmo que quando comparados individualmente. Os modelos que melhor se ajustaram aos dados experimentais foram os mesmos obtidos nos ensaios monocomponente, Langmuir para a AMP e Sips para o PAR. Da mesma forma que para os experimentos em coluna monocomponente, os ensaios multicomponentes demostraram que os tempos de ruptura e de saturação são maiores para o PAR. Entretanto, esses valores são menores do que na adsorção individual indicando que houve concorrência entre os fármacos pelos sítios do adsorvente. Os resultados encontrados indicam que a adsorção é uma alternativa viável para a remoção de fármacos, contribuindo, assim, para o avanço das pesquisas relacionadas ao tratamento de efluentes contaminados por estes poluentes. / Drugs are essential for preservation of human and animal health as well as for disease prevention. However, its high consumption associated with incorrect disposal and inefficient treatment of water and effluents can cause great damage to the environment such as bacterial resistance, for example. The objective of this work was to study the removal of ampicillin (AMP), atenolol (ATN) and paracetamol (PAR), drugs of three different classes, in aqueous solutions by adsorption technique in granular activated carbon (GAC). Adsorption experiments were carried out in batch evaluating the effect of parameters pH, contact time and concentration of solid adsorbent. The kinetic behavior of the adsorption of drugs in granular activated carbon was evaluated through the pseudofirst order, pseudo-second order and intraparticle diffusion models. Furthermore, equilibrium isotherms for these systems were made at different temperatures (15, 25 and 35 ° C) and analyzed using the Langmuir, Freundlich and Sips models. The adsorption process was also evaluated through thermodynamic tests. The fixed bed column adsorption was evaluated by experimental planning for drugs and the effects of mass of the adsorbent bed (0.5 to 1.5 g) and feed rate (10 - 15 ml min-1) were studied Also, in order to evaluate the behavior of the drugs when in mixture, adsorption tests were carried out in batch and in fixed bed column for the mixture of ampicillin and paracetamol. The best results found in the batch adsorption tests were: pH 6 and concentration of adsorbent solid of 10 g L-1 for the three drugs. The most suitable adsorption time was 90 minutes for ATN and 120 min for AMP and PAR. Under these conditions it was possible to obtain removals of 90%, 94% and 96% for ampicillin, atenolol and paracetamol respectively. The kinetic model that best described the adsorption process was the pseudo-first order for the ampicillin and paracetamol drugs and pseudo-second order for atenolol. The isotherms obtained for the drugs indicated that the adsorption process is of endothermic nature, that is, the adsorption is favored with the increase in temperature. For the AMP, the best isotherm adjustment was obtained by the Langmuir model at temperatures of 15 °C and 25 °C and by the Sips model at temperature of 35 °C. For the ATN, the best fit was obtained by the Freundlich model and, for PAR, the Sips model at the three temperatures studied. The thermodynamic tests indicated that the adsorption process of the drugs was favorable and spontaneous and confirmed the endothermic nature of the process Regarding the results obtained in adsorption in fixed bed column, it was observed that rupture and saturation times increase with the increase of the mass of solid present in the bed and decrease with the increase of flow. The adsorbent mass had a negative effect on the used bed fraction and was significant in the adsorption process of the three drugs. The feed flow was only significant in the adsorption in fixed bed of the AMP and had positive effect in the used bed fraction. The highest volumes of treated effluent were obtained with the largest mass of solid used (1,5 g) and with the lowest feed rate tested (10 mL min-1). In multicomponent adsorption in batch, it was found that there is competition between the drugs by the active sites of GAC available for adsorption. The results obtained in the adsorption isotherms tests showed that the behavior of the drugs in mixture is the same as when compared individually. The models that best fit the experimental data were the same ones obtained in the monocomponent tests, Langmuir for AMP and Sips for PAR. Similarly as for the monocomponent column experiments, the multicomponent tests showed that the break and saturation times are larger for the PAR. However, these values are lower than in individual adsorption indicating that there was competition between the drugs for the sites of the adsorbent. The results indicate that adsorption is a viable alternative for the removal of drugs, thus contributing to the advancement of research related to the treatment of effluents contaminated by these pollutants.
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Remoção dos fármacos atenolol, paracetamol e ampicilina por adsorção em carvão ativadoHaro, Nathalia Krummenauer January 2017 (has links)
Os fármacos são essenciais para a preservação da saúde do homem e de animais e também na prevenção de doenças. Entretanto, seu alto consumo associado ao descarte incorreto e aos tratamentos ineficientes de águas e efluentes podem trazer grandes prejuízos ao meio ambiente como, por exemplo, a resistência bacteriana. O objetivo deste trabalho foi estudar a remoção de ampicilina (AMP), atenolol (ATN) e paracetamol (PAR), fármacos de três classes distintas, em soluções aquosas através da técnica de adsorção em carvão ativado granular (CAG). Foram realizados experimentos de adsorção em batelada avaliando o efeito dos parâmetros pH, tempo de contato e concentração de sólido adsorvente. O comportamento cinético da adsorção dos fármacos em carvão ativado granular foi avaliado por meio dos modelos de pseudo-primeira ordem, pseudosegunda ordem e difusão intrapartícula. Ainda, isotermas de equilíbrio para estes sistemas foram construídas em diferentes temperaturas (15, 25 e 35 °C) e analisadas através dos modelos de Langmuir, Freundlich e Sips. O processo de adsorção também foi avaliado através de ensaios termodinâmicos. A adsorção em coluna de leito fixo foi avaliada utilizando planejamentos experimentais para os fármacos e os efeitos da massa do leito de adsorvente (0,5 – 1,5 g) e da vazão de alimentação (10 – 15 mL min-1) foram estudados Ainda, a fim de se avaliar o comportamento dos fármacos quando em mistura, foram realizados ensaios de adsorção em batelada e em coluna de leito fixo da mistura de ampicilina e paracetamol. Os melhores resultados encontrados nos ensaios de adsorção batelada foram: pH 6 e concentração de sólido adsorvente de 10 g L-1 para os três fármacos. O tempo de adsorção mais adequado foi de 90 minutos para o ATN e 120 min para AMP e PAR. Nessas condições foi possível obter remoções de 90 %, 94 % e 96 % para a ampicilina, atenolol e paracetamol, respectivamente. O modelo cinético que melhor descreveu o processo de adsorção foi o de pseudo-primeira ordem, para os fármacos ampicilina e paracetamol, e pseudo-segunda ordem para o atenolol. As isotermas obtidas para os fármacos indicaram que o processo de adsorção é de natureza endotérmica, ou seja, a adsorção é favorecida com o aumento da temperatura. Para a AMP, o melhor ajuste das isotermas foi obtido pelo modelo de Langmuir nas temperaturas de 15 ºC e 25 ºC e pelo modelo de Sips na temperatura de 35 ºC. Para o ATN, o melhor ajuste foi obtido pelo modelo de Freundlich e, para o PAR, o modelo de Sips, nas três temperaturas estudadas. Os ensaios termodinâmicos indicaram que o processo de adsorção dos fármacos é favorável e espontâneo e comprovou a natureza endotérmica do processo Em relação aos resultados obtidos na adsorção em coluna de leito fixo foi observado que os tempos de ruptura e de saturação aumentam com o aumento da massa de sólido presente no leito e diminuem com o aumento da vazão. A massa de adsorvente apresentou efeito negativo sobre a fração de leito utilizado e foi significativa no processo de adsorção dos três fármacos. Já a vazão de alimentação só foi significativa na adsorção em leito fixo da AMP e apresentou efeito positivo na fração de leito utilizado. Os maiores volumes de efluente tratado foram obtidos com a maior massa de sólido utilizada (1,5 g) e com a menor vazão de alimentação testada (10 mL min-1). Na adsorção multicomponente em batelada, verificou-se que há concorrência entre os fármacos pelos sítios ativos do CAG disponíveis para adsorção. Os resultados obtidos nos ensaios das isotermas de adsorção mostraram que o comportamento dos fármacos em mistura é o mesmo que quando comparados individualmente. Os modelos que melhor se ajustaram aos dados experimentais foram os mesmos obtidos nos ensaios monocomponente, Langmuir para a AMP e Sips para o PAR. Da mesma forma que para os experimentos em coluna monocomponente, os ensaios multicomponentes demostraram que os tempos de ruptura e de saturação são maiores para o PAR. Entretanto, esses valores são menores do que na adsorção individual indicando que houve concorrência entre os fármacos pelos sítios do adsorvente. Os resultados encontrados indicam que a adsorção é uma alternativa viável para a remoção de fármacos, contribuindo, assim, para o avanço das pesquisas relacionadas ao tratamento de efluentes contaminados por estes poluentes. / Drugs are essential for preservation of human and animal health as well as for disease prevention. However, its high consumption associated with incorrect disposal and inefficient treatment of water and effluents can cause great damage to the environment such as bacterial resistance, for example. The objective of this work was to study the removal of ampicillin (AMP), atenolol (ATN) and paracetamol (PAR), drugs of three different classes, in aqueous solutions by adsorption technique in granular activated carbon (GAC). Adsorption experiments were carried out in batch evaluating the effect of parameters pH, contact time and concentration of solid adsorbent. The kinetic behavior of the adsorption of drugs in granular activated carbon was evaluated through the pseudofirst order, pseudo-second order and intraparticle diffusion models. Furthermore, equilibrium isotherms for these systems were made at different temperatures (15, 25 and 35 ° C) and analyzed using the Langmuir, Freundlich and Sips models. The adsorption process was also evaluated through thermodynamic tests. The fixed bed column adsorption was evaluated by experimental planning for drugs and the effects of mass of the adsorbent bed (0.5 to 1.5 g) and feed rate (10 - 15 ml min-1) were studied Also, in order to evaluate the behavior of the drugs when in mixture, adsorption tests were carried out in batch and in fixed bed column for the mixture of ampicillin and paracetamol. The best results found in the batch adsorption tests were: pH 6 and concentration of adsorbent solid of 10 g L-1 for the three drugs. The most suitable adsorption time was 90 minutes for ATN and 120 min for AMP and PAR. Under these conditions it was possible to obtain removals of 90%, 94% and 96% for ampicillin, atenolol and paracetamol respectively. The kinetic model that best described the adsorption process was the pseudo-first order for the ampicillin and paracetamol drugs and pseudo-second order for atenolol. The isotherms obtained for the drugs indicated that the adsorption process is of endothermic nature, that is, the adsorption is favored with the increase in temperature. For the AMP, the best isotherm adjustment was obtained by the Langmuir model at temperatures of 15 °C and 25 °C and by the Sips model at temperature of 35 °C. For the ATN, the best fit was obtained by the Freundlich model and, for PAR, the Sips model at the three temperatures studied. The thermodynamic tests indicated that the adsorption process of the drugs was favorable and spontaneous and confirmed the endothermic nature of the process Regarding the results obtained in adsorption in fixed bed column, it was observed that rupture and saturation times increase with the increase of the mass of solid present in the bed and decrease with the increase of flow. The adsorbent mass had a negative effect on the used bed fraction and was significant in the adsorption process of the three drugs. The feed flow was only significant in the adsorption in fixed bed of the AMP and had positive effect in the used bed fraction. The highest volumes of treated effluent were obtained with the largest mass of solid used (1,5 g) and with the lowest feed rate tested (10 mL min-1). In multicomponent adsorption in batch, it was found that there is competition between the drugs by the active sites of GAC available for adsorption. The results obtained in the adsorption isotherms tests showed that the behavior of the drugs in mixture is the same as when compared individually. The models that best fit the experimental data were the same ones obtained in the monocomponent tests, Langmuir for AMP and Sips for PAR. Similarly as for the monocomponent column experiments, the multicomponent tests showed that the break and saturation times are larger for the PAR. However, these values are lower than in individual adsorption indicating that there was competition between the drugs for the sites of the adsorbent. The results indicate that adsorption is a viable alternative for the removal of drugs, thus contributing to the advancement of research related to the treatment of effluents contaminated by these pollutants.
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Remoção de Microcystis Aeruginosa e Microcistina-LR por coagulação, floculação, sedimentação e filtração seguida de coluna de carvão ativado granularOliveira, Silvânia Nóbrega 30 October 2012 (has links)
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Previous issue date: 2012-10-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The luxuriant proliferation of cyanobacteria in the water used as sources of drinking water is
increasing around the world.The presence of these microorganisms in raw water can difficult
the water treatment and make it more expensive. The main importance of health
cyanobacterial bloom is the possible release of cyanotoxins in the water, which can cause
serious risks to human health and unknown changes in aquatic biota. In the present study tests
were carried out in a bench scale to evaluate the efficiency of removal of whole cells of
Microcystis aeruginosa and the cyanotoxin microcystin-LR extracellular using coagulation,
flocculation, sedimentation and filtration followed by a column of activated granular carbon
produced in the northeast of Brazil. The water used was raw water from an eutrophic reservoir
with addition of M. aeruginosa cells from a fresh culture maintained in laboratory conditions
in order to obtain an initial concentration approximately with 105 cells.mL-1. The efficiency
observed was up to 90% of cells removal using aluminum sulfate at the concentration of 45
mg.L-1 and a coagulation pH equal at 5.5 in the water decanted (with dosages of 40 and 60
mg.L-1 of the coagulant and pH equal at 7.5 the percentage of cells removal was 35%). The
water effluent from the sand filter and the water effluent from the column of granular
activated carbon had averages of M. aeruginosa cells equals to 3,8 and 3,6 log cel.mL-1
respectively. The average concentration of microcystin-LR in the water effluent from the
GACC was 0,15 μg.L-1. Its value is below the limit of detection of the method (0,16 μg.L-1)
and after 60 hours ranged from 0,18 to 0,28 μg.L-1. Both values were below the maximum
allowed by ordinance 2914/11 Ministry of Health of 1 μg.L-1 microcystins in drinking water. / A proliferação luxuriante de cianobactérias na água dos mananciais usados como fontes de
água potável é cada vez mais frequente. A presença desses microrganismos na água bruta
pode dificultar e encarecer o tratamento, mas a principal importância sanitária do
florescimento de cianobactérias é a possível liberação de cianotoxinas na água, que podem
causar sérios agravos à saúde humana e alterações na biota aquática em geral. No presente
trabalho foram realizados ensaios, em escala de bancada, de avaliação da eficiência de
remoção de células inteiras de Microcystis aeruginosa e de uma de suas toxinas, microcistinaLR
extracelular, por coagulação, floculação, sedimentação e filtração seguida de coluna de
carvão ativado granular produzido na região nordeste utilizando-se água bruta de um
manancial eutrofizado adicionada de células de M. aeruginosa cultivadas em laboratório para
obter concentração inicial de aproximadamente 105 cel.mL-1. Observou-se eficiência de até
90% de remoção de células para dosagem superior a 45 mg.L-1 de sulfato de alumínio e pH de
coagulação de 5,5 na água decantada (para dosagens de 40 e 60 mg.L-1 do coagulante e pH de
7,5 o percentual de remoção de células foi de 35%). Na água filtrada e na água efluente a
coluna de carvão ativado granular, a concentração média de células de M. aeruginosa foi de
3,8 e 3,6 log cel.mL-1 respectivamente. A concentração media de MC-LR extracelular na água
efluente da Coluna de Carvão Ativado Granular (CCAG) foi de 0,15 µg.L-1 abaixo do limite
de detecção do método (0,16 µg.L-1) e após 60 horas variou de 0,18 a 0,28 µg.L-1 valores
abaixo do valor máximo permitido pela portaria 2914/11 do Ministério da Saúde de 1 µg.L-1
de microcistinas na água de beber.
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Lodos ativados com adi??o de carv?o ativado no tratamento combinado de lixiviado de aterro sanit?rio e esgoto dom?stico / Activated sludges with addition of activated carbon in the combined treatment of landfill leachate and domestic sewageDIAS, Albiane Carvalho 23 February 2017 (has links)
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2017 - Albiane Carvalho Dias.pdf: 1710937 bytes, checksum: 54d2634d67d97d4c119e2aa8507ca99b (MD5)
Previous issue date: 2017-02-23 / CAPES / The inappropriate management of leachate can cause negative environmental impacts, in order to compromise the availability and quality of natural resources, reason of to their complex composition and high polluter potential. One of the alternatives for the treatment of landfill leachate is its combined treatment with domestic sewage in sewage treatment plants, although higher proportions of the leachate in the sewage could compromise the efficiency of the process. This study aimed to evaluate the efficiency of the combined treatment of landfill leachate and domestic sewage in biomass and activated carbon systems. For this, were used sequential batch reactors in lab-scale and two types of activated carbon - granular (GAC) and pulverized (PAC). The work consisted of two stages, among them they are: the tests where the reactors were fed with different mixtures of leachate/synthetic sewage (0, 2, 5 e 10%) and concentrations of GAC (0, 2, 4 e 6 g/L) operating with residence times 23h and sludge ages 28 days; and tests where the reactors were fed with a mixture of 5% leachate/sewage; fixed a PAC concentration of 6 g/L and were operated on with differents HRT of 23, 16 and 8 hours and sludge ages of 28, 28, and 17 days, respectively. It has been evaluated, the difference between the two types of carbon regarding COD removal efficiency, in the following configurations: fixing the concentration of carbono (6 g/L) and the percentage of leachate in the feed (5% v/v), for the batch time of 23 h and sludge age of 28 d. For the first step, it was possible to verify that the COD removal efficiency was higher in the reactors containing GAC and biomass when comparedes to the reactor containing only biomass. And along this stage of the experiment it was possible to observe that after the increase of leachate concentration in the feed there was a significant drop in COD removal efficiency. In the evaluation of the PACT? process, it was verified that the reactor with HRT of 23 h was the one that presented the best COD and color removal efficiencies the process, 79 and 44%, respectively. In the comparative tests between the two types of carbon, the PAC system proved to be much more efficient in the removal of COD, presenting an average efficiency of 79% when compared to the GAC system (63%). / O gerenciamento inadequado do lixiviado pode causar impactos ambientais negativos, de forma a comprometer a disponibilidade e qualidade dos recursos naturais, devido sua composi??o complexa e seu elevado potencial poluidor. Uma das alternativas para o tratamento de lixiviado de aterros sanit?rios ? o seu tratamento combinado com esgoto dom?stico em esta??es de tratamento de esgoto, embora propor??es mais elevadas do lixiviado no esgoto possam comprometer a efici?ncia do processo. Este trabalho teve por objetivo avaliar a efici?ncia do tratamento combinado de lixiviado de aterro sanit?rio e esgoto dom?stico em sistemas com biomassa e carv?o ativado. Para isto, foram utilizados reatores em batelada sequencial em escala de laborat?rio e dois tipos de carv?o ativado- granular (CAG) e pulverizado (CAP). O trabalho foi constitu?do de duas etapas, dentre elas est?o: os ensaios onde os reatores foram alimentados com diferentes misturas de lixiviado/esgoto sint?tico (0, 2, 5 e 10%) e concentra??es de CAG (0, 2, 4 e 6 g/L) operando com tempos de resid?ncia de 23 h e idades do lodo de 28 dias; e ensaios onde os reatores foram alimentados com uma mistura de 5% de lixiviado/esgoto, fixado uma concentra??o de CAP de 6 g/L e foram operados com diferentes tempos de resid?ncia de 23, 16 e 8 horas e idades de lodo de 28, 28, e 17 dias, respectivamente. Avaliou-se, ainda, a diferen?a entre os dois tipos de carv?o quanto ? efici?ncia de remo??o de DQO, nas seguintes configura??es: fixando a concentra??o de carv?o (6 g/L) e o percentual de lixiviado na alimenta??o (5% v/v), para o tempo de batelada de 23 h e idade do lodo de 28 d. Para a primeira etapa, foi poss?vel verificar que a efici?ncia de remo??o de DQO foi superior nos reatores contendo CAG e biomassa quando comparados ao reator contendo apenas biomassa. E ao longo desta etapa do experimento foi poss?vel observar que ap?s o aumento da concentra??o de lixiviado na alimenta??o houve queda significativa na efici?ncia de remo??o de DQO. Na avalia??o do processo PACT?, verificou-se que o reator com tempo de resid?ncia de 23 h foi o que apresentou as melhores efici?ncias de remo??o de DQO e cor do processo, 79 e 44%, respectivamente. Nos testes comparativos entre os dois tipos de carv?o, o sistema com CAP mostrou-se muito mais eficiente na remo??o de DQO, apresentando efici?ncia m?dia de 79%, quando comparado ao sistema com CAG (63%).
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Sledování účinnosti odstraňování pesticidů ze zdrojů pitné vody vybranými adsorbenty / Monitoring the effectiveness of removing pesticides from drinking water sources by selected adsorbentsGottwald, Martin January 2019 (has links)
In the introductory part of this diploma thesis the pesticidal substances and their legislative requirements in drinking water are described. This is followed by a description of technologies in which pesticides can be removed and used in water treatment plants. In the practical part of the thesis is described description of the experimental procedure of the removal of pesticides on two selected adsorption materials (Filtrasorb F100 and Bayoxide E33) and subsequently this experiment is evaluated.
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Sledování pesticidních látek ve zdroji úpravny vody Hrdibořice a možnost jejich odstranění / Monitoring of pesticides in source of water treatment Hrdibořice and possibility of their removalBouchalová, Zuzana January 2017 (has links)
The thesis discusses possible ways to reduce or completely eliminate pesticide compounds from drinking water that are produced at a water treatment plant Hrdibořice. The work is divided into theoretical and practical parts. The theoretical part lists kinds of pesticides that occur in water, how they are reduced or eliminated. Furthermore, this section describes the existing water treatment technologies at the Central Committee Hrdibořice, including water sources. In the practical part, pilot tests on two types of filters models with filtering bed of granular activated carbon (hereinafter GAU) were carried out. On the basis of information obtained from the literature and on findings from the pilot tests, designs of technological equipment for pesticide removal from drinking water at water treatment Hrdiborice were carried out. Next, cost estimates for the proposed variant solutions including operating costs were suggested.
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Adsorpce pesticidů na granulovaném aktivním uhlí při úpravě vody / Adsorption of pesticides onto granular activated carbon in water treatment processKopecká, Ivana January 2010 (has links)
The diploma thesis is aimed at adsorption processes during the removal of pesticides onto granular activated carbon (GAC) in the process of drinking water treatment. Adsorption onto GAC represents an efficient method for pesticides removal. High adsorption efficiency can be significantly reduced due to the occurrence of natural organic matter (NOM) in raw water, which involves AOM (Algal Organic Matter) produced by phytoplankton. Analogous to NOM, AOM probably affects adsorption of pesticides by two different mechanisms - a direct site competition and pore blockage effect, in dependence on the different molecular weight of particular AOM fractions. Equilibrium batch and kinetic adsorption experiments were performed using two types of GAC (Norit 1240 and Filtrasorb 400) and two pesticides (terbuthylazine and alachlor). In order to examine the effect of AOM on adsorption of pesticides, raw GAC and GAC preloaded by AOM were used. The effect of pH on the competitive adsorption of AOM was also evaluated. A solid phase extraction (SPE) method and gas chromatography with electron capture detection (GC-ECD) were used to determine pesticides in water samples. AOM was characterized using fractionation onto sorptive resins. The representation of apparent molecular weights of AOM proteins was determined by...
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Removal of Microcystin-LR from Drinking Water Using Granular Activated CarbonVillars, Kathryn E., Villars 12 December 2018 (has links)
No description available.
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The Potential of Dissolved Air Flotation for PFAS Reduction in Norrvatten's Future Waterworks / Potentialen av Flotation för PFAS Reduktion i Norrvattens Framtida VattenverkVikström, Madeleine January 2023 (has links)
Norrvatten är en av Sveriges största dricksvattenproducenter. Med ett ökande behov av en större produktionskapacitet och nya regleringar, planerar dem att förbättra sin reningsprocess. En aspekt som kräver omfattande undersökning är val av reningsmetod för att nå den nya gränsen från Livsmedelsverket för fyra PFAS kemikalier. PFAS är en grupp kemikalier som är mänskligt producerade sedan 1950-talet, vilka är persistenta och farliga för människors hälsa. Deras stabilitet i miljön leder till att de ackumulerar i naturen och hamnar i mat och dricksvatten. För att uppnå de nya regleringarna måste Norrvatten minska sin PFAS4 koncentration från cirka 5.7 ng/L till 4 ng/L. PFAS-separationen är planerad att genomföras via antingen aktivt kol eller en kombination där flotation även implementeras. Aktivt kol har en bevisad möjlighet att separera och destruera PFAS4, men nyligen har indikationer på en potential hos flotation uppenbarats. Dock är forskningen kring dess effektivitet begränsad vilket medför ett behov av att utvärdera dess användbarhet. Denna rapport syftar till att förse Norrvatten med ett underlag på effektiviteten och gynnsamheten med flotation inför beslutet att implementera flotation. Av den anledningen undersöktes separationseffektiviteten som uppnås i en befintlig flotationsbassäng i Norrvattens vattenverk. Genom att mäta PFAS4 koncentrationen i inflödet, utflödet och slammet kunde en borttagningseffektivitet på 19-38% bestämmas för olika belastningar. Slamkoncentrationen mättes till ungefär 200-700 ng/L. Felkällor kunde identifieras i mätningarna eftersom massbalansen inte stämde överens trots att mätosäkerheten från analysen adderades. Dessutom gjordes en omanalys av två prover som skilde sig från det förväntade resultatet, vilket gav avsevärda skillnader i resultatet. Trots att några felkällor kunde identifieras kunde inte en fullständig förklaring till avvikelserna fastställas. Trots detta kunde slutsatser dras att den uppmätta separationseffektiviteten och slamkoncentrationen kunde förse ett korrekt intervall. Dessutom indikerade resultaten att flotation inte kan appliceras enskilt för att nå koncentrationsmålet utan bör kombineras med kompletterande kolfilter f ̈or att nå gränsvärdet. Flotation ger upphov till en mer koncentrerad ström av PFAS som kräver behandling för att eliminera kemikalierna från miljöns kretslopp. Flera potentiella behandlingsmetoder identifierades för hur slammet kan hanteras. Jämförelsen inkluderade aktivt kolfilter, jonbytare, membran, oxidationsprocesser, sonolys, förbränning, deponi, jordrening, flotation, skumfraktionering, behandling på reningsverk och återanvändning för jordförbättring. Metoderna jämfördes utifrån bevisad robusthet, kostnad och applicerbarhet. Ett möjligt slamhanteringsalternativ visade sig vara ett sekundärt steg med flotation, förbränning av det uppkoncentrerade slammet och behandling av permeatet med jonbytare. Med den föreslagna slamhanteringen kunde implementering av flotation utvärderas baserat på maximal PFAS destruktion, ekonomi, koldioxidutsläpp och energiförbrukning. Det visade sig att energiförbrukningen är större för processen som inkluderar flotation men koldioxidutsläppen är mindre. Dock är det möjligt att avgränsningarna för koldioxid kan ha gynnat flotationsprocessen eftersom utsläpp från reaktivering av kolfilter inkluderades men inte utsläpp från förbränning eller energiproduktion. PFAS destruktionen blev ungefär 1-2% större för processen med exklusivt kolfilter eftersom flotationsprocessen innehåller ytterligare en ström som släpper ut PFAS efter behandling med jonbytare. Det mest ekonomiska alternativet visade sig bero på koncentrationsgränsen där implementering av flotation var dyrare för en PFAS4 koncentration på 4 ng/L i dricksvattnet, men billigare vid en gräns på 3 ng/L. Slutligen upptäcktes det att volymen av sekundärt slam som beräknades att skickas till förbränning har en stor påverkan på driftkostnaderna. Därför bör optimeringar genomföras för att minimera den sekundära slamvolymen om flotation implementeras. / Norrvatten is one of the largest drinking water producers in Sweden. With the need to increase their production capacity and new regulations, they are planning to improve their treatment process. One aspect that requires extensive investigation, is the treatment approach to reach the new limit from the Swedish Food Agency of four PFAS chemicals. PFAS is a group of chemicals that have been humanely produced since the 1950s, which are persistent and hazardous to human health. Their environmental stability causes them to accumulate in nature and ends up in foods and drinking water. To fulfill the new regulations, Norrvatten has to decrease the PFAS4 concentration in their drinking water from approximately 5.7 ng/L to 4 ng/L. The removal is planned to be achieved through either activated carbon filters or a combination where dissolved air flotation is included. Activated carbon has a proven separation and destruction possibility for PFAS4 but recently, DAF has appeared to be a promising alternative. However, there is limited research on its efficiency, which establishes a need for investigations on the potential of DAF for PFAS removal. To navigate Norrvatten through the decision between exclusively applying GAC filters or implementing a combination with DAF, this thesis intends to provide a basis of its efficiency and favorability. Therefore, this thesis investigated the removal efficiency that was obtained in one existing DAF basin in Norrvattens waterworks. By measuring the PFAS4 concentration in the inlet, outlet, and sludge flow, a removal efficiency of 19-38% was acquired for different flow levels. In addition, the sludge concentration was measured to approximately 200-700 ng/L in the water phase. Presence of sources of errors could be identified in the measurements as the mass balance did not add up despite the addition of the measurement uncertainty in the analysis. Also, two samples were analyzed twice as the results differed from the expected results, which provided significant variations. Although some sources of error were identified, a full explanation for the differing results could not be disclosed. However, through some consistency, it was possible to conclude that the removal efficiency and sludge concentration could provide an accurate interval to illustrate the reality. In addition, the results indicate that DAF cannot be applied alone to reach the concentration goal, but has to be combined with additional GAC filters to reach the target. DAF provides a separation of PFAS into a sludge stream that requires treatment to remove the chemicals from the environmental cycle. To investigate how the sludge could be managed, several treatment methods were identified. The comparison included GAC, AIX, membranes, oxidation processes, sonolysis, incineration, landfill, soil cleaning, DAF, foam fractionation, treatment at a wastewater facility, and reuse for soil improvement. The methods were compared based on proven robustness, cost, and applicability. It was concluded that a viable alternative was to transfer the sludge to a second stage of DAF, incinerate the concentrated sludge, and treat the permeate with AIX. From the sludge management proposal, the implementation of DAF was analyzed based on maximum PFAS destruction, economics, carbon emissions, and energy requirements. It was found that the energy requirement was larger for the process including DAF but the carbon emissions are smaller. However, the delimitations on the carbon emissions may have been in favor of the DAF process as the GAC reactivation emissions are included but emissions due to incineration or energy production are excluded. The PFAS destruction was approximately 1-2% larger for the process that excluded DAF as an additional stream containing PFAS would be released into the environment after AIX, which is not present when only GAC is implemented. The economic out-come depended on the concentration limit, where implementation of DAF was more expensive for a treatment target of 4 ng/L in the drinking water and more economical for 3 ng/L. Lastly, it was found that the volume of the concentrated sludge that would be sent for incineration had a large impact on the operational cost. Therefore, if DAF is implemented optimizations are of relevance to minimize the volume of that stream.
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