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Estudo do potencial de contaminação de lixiviados gerados em aterros de resíduos da construção civil por meio de simulações em colunas de lixiviação / Study of the pollution potential of leachate of construction and demolition wastes landfills in lysimetersRodrigo Eduardo Córdoba 27 June 2014 (has links)
No Brasil, a Resolução CONAMA nº 307/2002 e a Resolução CONAMA nº 448/2012 definem que os resíduos da construção civil (RCC) classe A, caso não sejam reutilizados ou reciclados na forma de agregados, devem ser destinados para aterros de resíduos classe A de reservação de material para usos futuros. Porém, pequenas quantidades de resíduos de outras classes, e resíduos não inertes acabam dispostos neste tipo de aterro. Esse fato pode ser agravado devido esses aterros não possuírem impermeabilização de base e sistemas de drenagem de lixiviados, o que pode favorecer a migração desses lixiviados de RCC para reservas de água, e colocar em risco a saúde da população e o meio ambiente. Com intuito de contribuir nessa área de conhecimento o presente estudo teve por finalidade investigar o potencial de contaminação de lixiviados de aterros de resíduos da construção civil por meio de simulações em colunas de lixiviação. Para tanto, foi realizado um estudo por meio de duas etapas – simulação de lixiviação de amostras de RCC em colunas de lixiviação (saturadas e não saturadas), e coleta de água subterrânea do aterro de RCC classe A. Resultados da pesquisa apontaram que as amostras de agregados de RCC classe A foram classificadas, de acordo com a NBR 10.004 (ABNT, 2004), como sendo resíduos não perigosos e não inertes – Classe II A. A hipótese tema do estudo foi verificada, a qual apontou que existe potencial de contaminação dos lixiviados gerados em aterros de RCC Classe A, os quais podem vir a poluir ou contaminar o solo e as águas subterrâneas inviabilizando o uso dessas águas para consumo humano. As concentrações máximas dos lixiviados de RCC que excederam o valor máximo permitido para consumo humano nas simulações foram: sulfato (950 mg/L), dureza (11.280 mg/L), cor (124 uH), Pb (0,36 mg/L), Cd (0,075 mg/L), Ni (0,088 mg/L), Fe (0,658 mg/L), Ba (1,205 mg/L), Cr (0,125 mg/L), Mn (0,297 mg/L), e Al (3,44 mg/L). A pesquisa também contribuiu para melhoria de projetos, execução e controle de aterros de resíduos da construção civil, a fim de futuramente equacionar possíveis impactos negativos gerados por esse tipo de resíduo ao solo e recursos hídricos. / In Brazil, the resolutions nº 307/2002 and nº 448/2012 of the National Environmental Council (CONAMA) define that the construction and demolition (C&D) class A - reusable or recyclable wastes as aggregates, such as ceramic components, grout and concrete -, if not reused or recycled as aggregates, should be going to C&D wastes landfill. These wastes must be disposed in the soil for the reservation of segregated materials for future use or future use of the area. However, these landfills receive small quantities of wastes from other sources and non-inert wastes. This fact can be aggravated because the C&D wastes are disposed in these unlined landfills and without drains of leachate. In this context, the C&D wastes leachate may migrate to water supplies causing risks to both human health and the environment. In an attempt to contribute to this area of knowledge, this project aims to investigate the pollution potential of leachate of construction and demolition wastes landfills in lysimeters. A survey will be conducted in two stages – simulation of leachate samples of C&D wastes lysimeters (saturated and unsaturated), and study of the C&D wastes landfill of the city through the collection of groundwater. Results of the research classified, for metals, the samples of aggregates of C&D wastes class A – such as ceramic components (bricks, blocks), grout and concrete – as non-hazardous and non-inert. The pollution of leachate of C&D wastes landfills was observed. The presence of these contaminants could affect the use of this water for human consumption. The parameters that exceeded the maximum value for human consumption were: sulfate (950 mg/L), hardness (11,280 mg/L), color (124 uH), Pb (0.36 mg/L), Cd (0.075 mg/L), Ni (0.088 mg/L), Fe (0.658 mg/L), Ba (1,205 mg/L) Cr (0.125 mg/L) Mn (0,297 mg/L), and Al (3.44 mg/L ).The research identified requirements for improvement projects, execution and control of C&D wastes landfills to minimize future potential adverse impacts generated by these residues in water resources.
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Tratamento eletrolítico de lixiviado de aterro sanitário = Electrolytic treatment of landfill leachate / Electrolytic treatment of landfill leachateSilveira, Jefferson Eduardo, 1986- 19 December 2012 (has links)
Orientador: Peterson Bueno de Moraes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Tecnologia / Made available in DSpace on 2018-08-21T23:07:04Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: A crescente degradação dos corpos d'água é assunto de constante interesse dos pesquisadores, da opinião pública e da mídia, devido à preocupação com a saúde pública, com os meios de produção e no legado às gerações futuras. Embora nos últimos anos as engenharias química, sanitária e ambiental tenham tido um significativo avanço nos métodos para tratamento de resíduos, alguns tipos de efluentes de composição complexa, como o lixiviado de aterro sanitário, não são adequadamente tratados pelos processos convencionais. Neste trabalho, propôs-se o uso da tecnologia eletroquímica, já utilizada na remedição de diversos tipos de resíduos e efluentes, para o desenvolvimento e aperfeiçoamento de um reator eletroquímico, em escala piloto, para tratamento do lixiviado do aterro sanitário do município de Limeira-SP. O lixiviado de aterro sanitário é um líquido escuro, com potencial patogênico, toxicológico e que pode conter compostos orgânicos como fenóis, pesticidas e íons metálicos. Foi utilizado um reator eletroquímico com eletrodos de titânio recobertos com 70%TiO2/30%RuO2 operando em batelada com recirculação, visando à redução da cor, carga orgânica e toxicidade. A partir dos resultados dos parâmetros físico-químico e biológicos, o sistema foi otimizado quanto à vazão, densidade de corrente, concentração de eletrólitos suporte e tempo de tratamento. Após 60 minutos de tratamento em densidade de corrente de 250 mA cm-2, concentração de eletrólito de 0,5 M de NaCl e vazão de 400 L h-1 foi possível remover 80% de DQO, 75% de N-NH3, 65% de COT e 90% de DBO. Levando-se em conta somente a remoção de amônia, a densidade de corrente mínima de 25 mA cm-2 já teve excelente desempenho após 30 minutos de tratamento. O sistema pode ser considerado economicamente viável para tratar este tipo de efluente em comparação aos tratamentos convencionais normalmente utilizados, com a vantagem de ser rápido, ocupar pouco espaço e não gerar lodo / Abstract: The increase in deterioration in the quality of water bodies is a subject of interest for researchers, public and media due to concern about public health. Although chemical engineering and environmental sciences have been experiencing lately significative advance in methods for wastewaters treatment, some types of effluents with complex composition such as landfill leachate are not adequately treated by conventional processes. In this work, we proposed the use of electrochemical technology, already used in the remediation of several types of waste and effluents, for development and improvement of an electrochemical pilot scale flow reactor for the treatment of raw landfill leachate from Limeira city, SP. The landfill leachate is a dark liquid with toxicological and pathogenic potential and may contain organic compounds such as phenols, pesticides and metallic ions. We used an electrochemical reactor with titanium oxide electrodes coated with 70% TiO2/30% RuO2 operating in batch recirculation mode, aiming to reduce color, organic load and toxicity. The electrochemical system was optimized from physicochemical and biological analyses considering the flow rate, current density, supporting electrolyte concentration and treatment time. Tests in 60 minutes at 250 mA cm-2, NaCl 0.5 M and flow rate of 400 L h-1 resulted on 80% COD, 75% NH3 - N, 65% TOC and 90% of BOD removal. Considering solely the removal of ammonia, 25 mA cm-2 was sufficed to reach a good performance in 30 minutes of treatment. The system showed be economically interesting for the treatment of this type of effluent when compared to conventional treatments normally used, because have the following advantages: higher degradation rates, small footprint, zero or low-generation of sludge / Mestrado / Tecnologia e Inovação / Mestre em Tecnologia
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Impact de l'évolution des déchets d'une installation de stockage de déchets non dangereux sur l'environnement - Site d'étude : l'ISDND d'Etueffont (Territoire de Belfort - France) / Environnmental impact assessment of a municipal solid waste landfill : Experimental site : the Etuffont landfill ( Belfort Aera-France)Grisey, Elise 26 June 2013 (has links)
Ce travail a pour objectif d’étudier l’impact d’une installation de stockage de déchets nondangereux sur l’eau souterraine. L’ISDND d’Étueffont (90) dont le mode d’exploitation associedes prétraitements mécanique et biologique (broyage et maturation aérobie) comporte un casiernon sécurisé ainsi qu’un casier étanche. La caractérisation des lixiviats sur 21 ans (1989-2010)montre une dégradation rapide des déchets. Un état de stabilisation est atteint en fin de suivi. Lesprétraitements ont permis d’accélérer la dégradation des déchets et de réduire le potentiel polluantde l’ISDND. Les lixiviats sont traités in situ par lagunage naturel. Bien que cette technique soitpeu répandue pour le traitement des lixiviats, elle offre pourtant des abattements significatifs (75-90 %) de la matière organique, des matières en suspension, de l’azote et du phosphore. Lesprécédentes études ayant démontré une contamination de l’eau souterraine par les lixiviats, unedélimitation du panache de contamination a été entreprise en combinant des prospectionsgéophysiques du secteur (tomographie de résistivité électrique) et des analyses physico-Chimiquesde l’eau. Les résultats montrent une infiltration des lixiviats à la base du casier non sécurisé ainsiqu’au travers de la géomembrane du casier sécurisé. Une légère infiltration des eaux de lagunagea aussi été observée au niveau des lagunes. Le panache a une étendue limitée et se concentreessentiellement sous la base de l’ISDND. L’ensemble des résultats a permis de cibler les zonescontaminées et de définir les paramètres physico-Chimiques à surveiller dans le cadre du suivipost-Exploitation auquel est soumise l’ISDND jusqu’en 2031. / The purpose of this work was to evaluate the impact of a landfill on groundwater quality.Municipal solid waste from the Etueffont landfill (Belfort area, France) was mechanically andbiologically treated (shredding and aerobic composting) before being disposed of in an unlinedarea and in a lined cell. The leachate characterization performed over a 21-Year period (1989-2010) showed a rapid degradation of waste. A steady state was reached at the end of themonitoring. Waste pretreatment enhanced the rate of biodegradation and reduced the pollutionpotential of the landfill. The leachate produced was treated on site in a natural lagooning. Whilelagooning is not a widespread practice for leachate treatment, significant removal (75-90 %) oforganic matter, suspended solids, nitrogen and phosphorus was observed. In previous studies,groundwater contamination was highlighted around the landfill. As a consequence, geophysicalinvestigations of the area by electrical resistivity tomography and physico-Chemical analyses wereconducted in order to delineate the contamination plume. The results showed leachate infiltrationinto the soil below the unlined part of the landfill and leakage through the watertightgeomembrane of the lined cell. Seepage of wastewater into the soil below the lagoons was alsoobserved. The extent of contamination plume was limited and was mostly limited to the landfillboundaries. The results of this work allowed to determine the location of the contaminated areasand helped to choose the appropriate physico-Chemical analytes of the post-Closure groundwatermonitoring program, which will be applied to the landfill until the end of 2031.
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Nouveaux procédés de bioremédiation pour le traitement des sols et des sédiments sélénifères / Novel bioremediation processes for treatment of seleniferous soils and sedimentWadgaonkar, 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
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Análise de aproveitamento energético em aterros sanitários baseada em cenários de produção de efluentesThomazoni, André Luis Ribeiro January 2014 (has links)
O aumento da preocupação de soluções ambientalmente adequadas e energeticamente eficientes, aliado às recentes mudanças nas diretrizes políticas Brasileiras em relação à gestão e ao gerenciamento de resíduos sólidos e suas práticas de disposição final, permite a oportunidade de investigar a recuperação energética e o abatimento dos efluentes gerados por aterros sanitários. O presente trabalho explora, separadamente, o uso de modelo de previsão de produção de biogás baseado no decaimento de primeira ordem, e para a estimativa de produção de lixiviado, aplica-se o método do balanço hídrico (MBH). A partir de variação dos principais parâmetros de entrada de cada modelo, obtêm-se cenários de produção de biogás e estimativas da capacidade de geração máxima e mínima de lixiviado para o aterro sanitário de Guajuviras (Canoas - RS, Brasil). Tomando os resultados de geração de lixiviado e de biogás calculados, estima-se o potencial energético disponível e o desempenho de três diferentes sistemas de conversão energética propostos: geração elétrica por motogeradores, evaporação de lixiviado em regime de cogeração com motogeradores, motogeradores com trocadores de calor em regime de cogeração e sistema de evaporação de lixiviado (LES). Resultados obtidos para o período analisado, mostram que a produção elétrica do cenário mais conservador está na faixa entre 17.300 a 18.800 MWh, enquanto que a produção de energia elétrica do cenário otimista atinge valores entre 416.976 e 459.900 MWh. Já para a evaporação de lixiviado, os volumes evaporados em regime de cogeração variaram de 1 a 70% em relação ao volume de lixiviado gerado pelo aterro sanitário, enquanto que o LES, considerando o cenário otimista, foi capaz de evaporar 100% do lixiviado durante 18 anos. / The growing concern on environmentally suitable and energy efficient solutions allied with the recent changes in the Brazilian policies on the solid waste management and its final disposal practices, enables an opportunity to investigate the energy recovery and abatement of landfills emissions. The present work explores separately the utilization of 1st order decay model for assess the landfill gas (LFG) production, and applies the water budget method for prediction of leachate generation. Ranging the main input parameters on each model, were obtained distinct scenarios for LFG production and the maximum and minimum leachate generation capacity of Guajuviras landfill (Canoas- RS, Brazil). Based in the calculated results for leachate and LFG production were assessed the available energetic potential and the performance of three distinct energetic conversion systems: motogenerators, heat exchangers in cogeneration with motogenerators and leachate evaporation system (LES). Results for the analyzed period show that the electric generation for conservative scenario ranges between 17.300 to 18.800 MWh, whereas, the electricity production for more optimistic scenario ranges between 416.976 to 459.900 MWh. As for the leachate evaporation, the evaporated volume by the cogeneration system reaches values between 1 to 70% of the leachate produced by the landfill, whereas, the LES, considering the optimistic scenario, is able to evaporate all the generated leachate by the landfill among 18 years.
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Analýza vodných výluhů biouhlu pomocí separačních metod / Analysis of biochar aqueous extracts by separation methodsTučková, Dominika January 2019 (has links)
This master's thesis deals with the analysis of biochar extracts by separation methods. All analyzed biochar was produced from waterworks sludge by microwave pyrolysis. The aim of the thesis is the optimization of the sample preparation method and its analysis in a laboratory environment. With the ever-growing world population, the problem of a sustainable economy in both agriculture and waste management is becoming increasingly urgent. This fact has led most countries to consider promoting the so-called Circular Economy. The use of sewage sludge as a feedstock for biochar production is perfectly in line with this strategy. So far, however, the short term and the long term benefits and risks of using biochar have not been sufficiently described. Potentially hazardous organic substances were extracted from the biochar extracts by three techniques: liquid-liquid extraction, solid-phase extraction, and solid- phase micro-extraction. The obtained samples were analyzed using the GS-MS/TOF method. The individual methods were compared. Several biochar samples from WWTP Brno and WWTP Drahovice were selected and analyzed to verify the suitability of the selected sample analysis method.
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Comparaison des réponses de quatre espèces de saule à divers traitements d’inondation et de surfertilisation en azoteAuger, Camille 10 1900 (has links)
My master's work was done within the context of the PhytoVaLix project, a research project that brings together researchers from the Université de Montréal and private companies. The goal of this project is to develop a technology for the phytotreatment of leachate from engineered landfill sites using willows to replace conventional techniques. A filtering plantation of miyabeana willow (Salix miyabeana) is currently in place on the experimental site. The willows are watered with leachate so that they use ammoniacal nitrogen, the main pollutant, for their growth. In my study, I focused on the morphological and physiological responses developed by four willow species when subjected to various treatments combining flooding and nitrogen overfertilization. The study aimed to compare the potential of these species for nitrogenous water phytoremediation as well as two leachate application methods. Responses to flooding and overfertilization with nitrogen varied and reveal much about the strategies adopted by each species. The biomass of S. miyabeana, S. amygdaloides and S. nigra was not impacted by the leachate treatments, while S. bebbiana suffered greatly from the flooding periods. The native species S. nigra and S. amygdaloides positively stood out in their ability to remove nitrogen from leachate (>75 kg/ha). It would be relevant to continue research on these two with the aim of using them in projects where leachate phytotreatment and biodiversity go hand in hand. / Mon travail de maitrise a été réalisé dans le cadre du projet PhytoVaLix, un projet de recherche
qui réunit des chercheurs de l'Université de Montréal et des entreprises privées. Le but de ce
projet est de développer une technologie de phytotraitement de lixiviat provenant de lieux
d’enfouissement technique à l’aide de saules pour remplacer les techniques conventionnelles.
Une plantation filtrante de saule miyabeana (Salix miyabeana) est présentement en place sur le
site expérimental. Les saules y sont arrosés avec du lixiviat afin qu’ils utilisent l’azote ammoniacal,
le polluant principal, pour leur croissance. Dans mon étude, je me suis intéressée aux réponses
morphologiques et physiologiques développées par quatre espèces de saule lorsqu’elles sont
soumises à divers traitements combinant l’inondation et la surfertilisation à l’azote. L’étude avait
comme objectif de comparer le potentiel de ces espèces pour la phytoremédiation d’eau azotée
et de deux méthodes d’application du lixiviat. Les réponses à l’inondation et à la surfertilisation à
l’azote furent variées et en révèlent beaucoup sur les stratégies adoptées par chacune des
espèces. La biomasse de S. miyabeana, S. amygdaloides et S. nigra ne fut pas impactée par les
traitements de lixiviat, alors que S. bebbiana a grandement souffert des périodes d’inondation.
Les espèces indigènes S. nigra et S. amygdaloides se sont positivement démarqués quant à leur
capacité à retirer l’azote du lixiviat (>75 kg/ha). Il serait pertinent de continuer à faire des
recherches sur celles-ci dans le but de les utiliser dans des projets où le phytotraitement du lixiviat
et la biodiversité vont de pair.
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Investigation of unknown groundwater flows to two leachate ponds at Hovgården / Undersökning av okända grundvattenflöden till lakdammar på HovgårdenNordström, Katja January 2023 (has links)
The leaching of groundwater into two polishing ponds, the last step in the wastewater treatment process on Hovgarden waste facility, was examined. The focus of this study was to analyse the PFAS composition profile (fingerprint) to trace the leaching groundwater. PFASs are very persistent man-made substances, used invarious fields and have been linked to several health issues. Polishing pond data and groundwater data for ions and PFAS was collected, compiled with old data and surveyed, mainly by using principle component analysis (PCA). The results indicate that there is a water flow and a mass flow of ions to the ponds, and possibly also a flow of PFAS. The ponds appear to have a different composition, which possible could be the result of a mass flow, however the macro ion distributionis similar. Of the groundwater wells, data suggests that 18G09, P3 IN and P8 were most affected by the landfill. PFOA was the most detected PFAS, and the sampling points with the highest concentration of PFAS was 18G09, P3 IN and the first sampling point (R1) in the wastewater treatment plant. While no apparent correlation between the polishing ponds and groundwater wells were discovered,data suggest that the leaching may come from some of the wells more affected by the landfill.
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A Non-isolated Half Bridge Buck-based Converter For Vrm Application And Small Signal Modeling Of A Non-conventional Two Phase BuBatarseh, Majd 01 January 2006 (has links)
This dissertation is about treatment of the nonbiodegradable organic content of landfill leachate by chemical oxidation combined with biological treatment. It is divided into three parts. In the first part, ferrate was compared to Fenton's reagent for the purpose of removing non-biodegradable organic compounds from mature leachate. Oxidation conditions (time, pH, and dose) were optimized to yield maximum organic removal using two leachate samples from 20 and 12-year old solid waste cells. Results from this research demonstrated that ferrate and Fenton's reagent had similar optimum pH ranges (3-5), but different organic removal capacities, ranging from 54 to 79 % of initial leachate organic contents. An advantage of ferrate was that it was relatively effective over a wide pH range (Fenton's reagent lost its reactivity outside optimum pH range). Advantages associated with Fenton's reagent include a higher organic removal capacity, production of more oxidized organic compounds (measured as chemical oxygen demand/dissolved organic carbon), and production of more biodegradable byproducts (measured as 5-day biochemical oxygen demand/chemical oxygen demand). Finally, both treatments were found to oxidize larger molecules (>1000 dalton) and produce smaller molecules, as indicated by an increase in smaller molecule contribution to organic carbon. In part two, effects of Fenton's reagent treatment on biodegradability of three landfill leachates collected from a Florida landfill were evaluated using biochemical oxygen demand (BOD), biochemical methane potential (BMP), and tertamethylammonium hydroxide (TMAH) thermochemolysis gas chromatography/mass spectrometry (GC/MS). The hypothesis was that Fenton's reagent will remove refractory compounds that inhibit biodegradation and will produce smaller, more biodegradable organic molecules which will result in an increase in BOD and BMP values. Both BOD and BMP results demonstrated that Fenton's reagent treatment did not convert mature leachate to biodegradable leachate, as indicated by a low BOD5 expressed as C /dissolved organic carbon (DOC) ratio of almost 0.15 in treated samples and a low net methane production / theoretical methane potential (less than 0.15). Ultimate BOD only slightly increased. However the first-order BOD reaction rate increased by more than five fold, suggesting that Fenton's reagent removed refractory and inhibitory compounds. BMP results demonstrated that the ratio of CO2/CH4 produced during anaerobic biodegradation did not increase in treated leachate (compared to untreated), indicating that small biodegradable organic acids produced by oxidation were removed by coagulation promoted by Fenton's reagent. Finally, the TMAH thermochemolysis results showed that several of the refractory and inhibitory compounds were detected fewer times in treated samples and that carboxylic acids did not appear in treated samples. In the third part of this dissertation the application of flushing/Fenton's reagent oxidation to produce sustainable solid waste cells was evaluated. A treatment similar to pump and treat process utilizing Fenton's reagent on-site treated leachate combined with in-situ aeration was proposed. Treated leachate would be recycled to the landfill cell flushes releasable nonbiodegradable carbon from the cell and oxidizes it externally. This technique was demonstrated to have treatment cost and time benefits over other alternatives for producing completely stable solid waste cells such as anaerobic flushing and biological and/or mechanical pretreatment of solid waste (used in the EU).
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En studie om lakvattenhantering vid Gräfsåsensavfallsanläggning : En studie i syfte att föreslå lämpliga system avreningsteknikerKarlström, Pontus January 2023 (has links)
För att främja en hållbar utveckling har FN satt upp 17 vägledande globala miljömål som nationell lagstiftning bör utformas efter, vilket Sverige har gjort. För att se till att miljölagstiftningen följs av verksamheter utövas tillsyn mot vissa typer av verksamheter, bland annat deponier. Deponier är bland annat miljöfarliga för att de kan släppa ut lakvatten till omgivande miljö. Tillsynsmyndigheter för Gräfsåsens avfallsanläggning har anmärkt på att vissa av deras utsläppsvillkor för lakvatten ej uppnås. Studien ska, med utgångspunkt från relevanta faktorer för val av reningsteknik (emissionskrav, lakvattnets karaktärisering & lakvattenproduktion), gällande villkor från utsedda tillsynsmyndigheter och styrdokumentet BREF utreda två lämpliga system avreningstekniker för lakvatten samt eventuella återupprepande reningssteg, vid Gräfsåsens avfallsanläggning. Hänsyn kommer även tas till tidigare genomförda pilotstudier för lakvattenhantering vid Gräfsåsens avfallsanläggning, och vilka övergripande slutsatsersom kan dras från dem. Karaktäriseringen utgick från att inhämta historiska data från provtagningar, som jämfördes med BREF:s riktvärden för relevanta parametrar samt nuvarandeutsläppsvillkor. Resultaten visade att reningsteknikerna skulle inriktas mot avskiljning av organiskt material (TOC & BOD7), långkedjiga PFAS, totalt oorganiskt kväve samt totalkväve. Försedimenteringsdamm valdes för att jämna ut lakvattenflödet samt minska mängdenorganiskt material och metaller som kan försämra biologisk rening. Luftad damm och översilningsyta valdes för att de kan minska mängden kväve, organiskt material ochmetaller. Skumfraktionering och adsorptionsfilter valdes för att effektivt avskilja långkedjiga PFAS. Studien har visat att Gräfsåsens avfallsanläggning behöver installera en försedimenteringsdamm samt utöka sin biologiska rening. Tidigare använda reningstekniker som luftad damm, adsorptionsfilter samt våtmark har ej optimeratstillräckligt. / To promote sustainable developement, the UN has set up 17 global environmental goals that national legislation should incorporate. To ensure that environmental legislation is followed by certain practioners, supervision is performed. Landfills are seen as an environmentally hazardous activity that need supervision, mainly due to the fact that environmentally hazardous substances like leachate water could be spread to the environment. Supervisory authorities for Gräfsåsen avfallsanläggning have noted that some of their emission requirements for leachate water are not fulfilled. The study shall, based on relevant factors for the selection of treatment technology (emission requirements, characterization of leachate & production of leachate), current conditions from appointed supervisory authorities, the steering document BREF, investigate two suitable systems of treatment techniques for leachate, at Gräfsåsens avfallsanläggning. Consideration will also be given to previously completed pilot studiesfor leachate management at Gräfsåsens avfallsanläggning, and general conclusions that can be drawn from them. The characterization was based on gathering historical measurement data, and then compare the data to BREF guideline values for relevant parameters as well as current emission requirements.The results showed that treatment techniques should be aimed at removing organic matter, long- chained PFAS, total inorganic nitrogen & total nitrogen. Pre- sedimentation ponds were chosen to even out the leachate flow and reduce the amount of organic matter and metals that could impair biological treatment. Aerated pond and overflow area were chosen because they can reduce the amount of nitrogen, organic matter and metals. Foamfractionation and adsorption filter was chosen to efficiently separate long-chained PFAS. The study has shown that Gräfsåsens avfallsanläggning needs to install a presedimentation pond and expand its biological treatment. Previously used treatment techniques such as aerated pond, adsorption filter and wetlands have not been sufficiently optimized / <p>2023-06-02</p>
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