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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.
91

Estudo da tratabilidade do lixiviado de aterro sanitário pelos processos oxidativos avançados foto-Fenton, ozônio e ozônio combinado com peróxido de hidrogênio / Study of treatability of landfill leachate by advanced oxidation processes photo-Fenton, ozone and ozone combined with hydrogen peroxide

Monteiro, Luciano do Valle 05 June 2012 (has links)
O lixiviado de aterro sanitário possui constituição complexa e é altamente poluente. Neste contexto, os processos oxidativos avançados se destacam como pré-tratamento, objetivando a remoção ou diminuição da recalcitrância do lixiviado. Neste trabalho foram utilizados os Processos Oxidativos Avançados (POAs) foto-Fenton, ozônio e ozônio combinado com peróxido de hidrogênio. Avaliou-se a influência do pré-tratamento por air-stripping, a variação na produção de ozônio em 80 e 100%, a melhor dose de peróxido de hidrogênio correspondente a 20, 40 e 80% da dose de 6g O3/L empregada nos tratamentos com ozônio, a remoção de matéria orgânica, nitrogênio amoniacal total (NAT), alcalinidade, sólidos dissolvidos totais (SDT) (cloretos), produção de nitrito e nitrato, melhor razão molar [H2O2]/[Fe2+] para o tempo de contato de 80 min no foto-Fenton, uso do número médio de oxidação do carbono (NMOC) e a quantificação do ácido oxálico formado após a aplicação dos POAs. O tratamento por O3/H2O2 (1,2 g H2O2/L e produção de O3 em 80%) obteve a maior remoção de matéria orgânica, 0,14 g massa removida de Carbono Orgânico Total (COT) / massa consumida de O3 e 0,43 g/g para a Demanda Química de Oxigênio (DQO). Quanto ao foto-Fenton, averiguou-se o máximo de 74% remoção de COT e 65% remoção DQO para a razão molar [H2O2]/[Fe2+] igual a 2. Também se notou formação de sólidos sedimentáveis neste processo aplicado ao lixiviado bruto. O pré-tratamento por air-stripping não promoveu incremento na remoção de matéria orgânica. As concentrações de NAT, alcalinidade, SDT (cloretos) se mantiveram elevadas após a aplicação dos POA. Ocorreu formação de nitrato em todos os tratamentos. O uso do NMOC foi adequado e demonstrou ocorrência de oxidação nos processos. A quantificação do ácido oxálico formado após a aplicação dos POAs não foi apropriada nesta pesquisa. / The landfill leachate is a major waste produced by the landfill and its constitution complex and highly polluting motivate research in order to adapt their disposal on the environment. In this context, the advanced oxidation processes stand out as a pretreatment, in order to remove or decrease the recalcitrance of the leachate. In this work we used the photo-Fenton AOPs, ozone and ozone combined with hydrogen peroxide. We evaluated the effect of pretreatment for air-stripping, the variation in the production of ozone 80 and 100%, the best dose of hydrogen peroxide equal to 20, 40 and 80% of the dose of 6g O3/ L used in the treatments with ozone, the removal of organic matter, total ammonia nitrogen, alkalinity, dissolved solids (chlorides), production of nitrite and nitrate, best molar ratio [H2O2]/[Fe2+] to the contact time of 80 min in the photo-Fenton, average number of carbon oxidation use and the measurement of oxalic acid formed after application of the AOPs. The AOP O3/H2O2 (1.2g H2O2/L and O3 production by 80%) had the highest removal of organic matter, 0.14 g of TOC removed mass/ mass consumed O3 and 0.43 g/g for COD. As for the photo-Fenton, it was found a maximum of 74% removal of TOC and 65% for COD removal molar ratio [H2O2]/[Fe2+] equal to 2. It was also noted the formation of settle able solids in the process applied to the raw leachate. Pretreatment by air-stripping did not promote an increase in organic matter removal. Total ammonia nitrogen concentrations, alkalinity, dissolved solids (chlorides) remained high after application of the AOP, indicating possible oxidant demand. For nitrate formation occurred in all treatments, while only the photo-Fenton was no formation of nitrite. The use of average number of carbon oxidation was adequate and showed occurrence of oxidation processes. The quantification of oxalic acid formed after the application of AOPs was not appropriate in this research.
92

Tratamento consorciado de esgoto sanitário com lixiviados de aterros sanitários, lodo de tanques sépticos e efluentes de sanitários químicos por lodos ativados em batelada na ETE Canoas - CORSAN

Souza, Ândrea Aline Rosa de 31 March 2011 (has links)
Submitted by Mariana Dornelles Vargas (marianadv) on 2015-05-12T12:29:45Z No. of bitstreams: 1 tratamento_consorciado.pdf: 6140063 bytes, checksum: 2e4f0cc893d0de295c3aa7272060c547 (MD5) / Made available in DSpace on 2015-05-12T12:29:45Z (GMT). No. of bitstreams: 1 tratamento_consorciado.pdf: 6140063 bytes, checksum: 2e4f0cc893d0de295c3aa7272060c547 (MD5) Previous issue date: 2011-03-31 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / No Brasil, apenas uma pequena parcela do esgoto sanitário coletado é efetivamente tratado. Entretanto, no âmbito urbano há a geração de outros tipos de efluentes tais como lodos de tanques sépticos, neste caso considerado um efluente devido ao teor de água superior a 90%, efluentes de sanitários químicos e lixiviados de aterro sanitários, todos gerados a partir de atividades urbanas, e que necessitam de tratamento adequado para disposição final. O tratamento consorciado destes efluentes externos com esgoto sanitário tem sido utilizado como estratégia para diminuir os custos no tratamento. No entanto, devido a grande variabilidade de composição e concentração, estes efluentes têm difícil tratabilidade, principalmente em estações convencionais. Ainda não há consenso sobre os impactos provocados por esta mistura de efluentes sobre os processos de tratamento encontrados nas ETE's, nem sobre a proporção segura para a diluição a ser adotada em relação ao esgoto sanitário. A ETE Canoas - CORSAN possui um sistema de lodos ativados operando em batelada, tratando de forma consorciada esgotos sanitários, lixiviados de aterros sanitários, lodos de tanques sépticos e efluentes de sanitários químicos, sem uma quantidade máxima estipulada para o recebimento destes efluentes externos. Nesta pesquisa buscou-se caracterizar a mistura afluente e avaliar o impacto do tratamento combinado sobre as condições operacionais da ETE, bem como o seu desempenho na remoção de matéria orgânica e nutrientes, no período de janeiro de 2009 a agosto de 2010. Verificou-se que o percentual de diluição dos efluentes externos no ES variou entre 2,1% e 11,3% e que a contribuição destes efluentes para a carga total da DQO variou entre 14% e 74%. A composição físico-química da mistura afluente ao reator biológico influenciou na composição da microbiota presente no RSB. O impacto mais freqüentemente observado pela entrada de cargas de choque foi a perda de biomassa, devido a problemas de floculação e sedimentação, como o bulking. A ocorrência de cargas de choque decorrentes da entrada de efluentes externos promoveu um aumento do IVL de 46 mL/g para 287 mL/g, da mesma forma verificou-se um aumento da relação A/M, que passou de 0,42 d-¹ para 0,82 d-¹. Entre os metais pesquisados o Ca, Fe e K foram encontrados em maiores percentuais nas amostras de efluentes externos, correspondendo a 15,8%, 10,4% e 10,1%, respectivamente. Também foram detectados teores de Cu, Zn, Ti, Cr, em menores percentuais. No lodo biológico foram detectados 56% de Fe, 16% de Ca, 10% de Si e 8% de S, adsorvidos nos flocos, além Zn (4%), Cu (3%), Mn (1,5%) e K (1,2%). A exposição freqüente da microbiota a cargas de choque foi o principal efeito a colaborar no decréscimo das eficiências de remoção de SST, DBO5, DQO, Ptotal e N-NH4 +, prejudicando a qualidade do efluente final. A adoção de uma unidade de recebimento e tratamento preliminar dos efluentes externos permitirá um maior controle operacional na dinâmica de recebimento e tratamento dos efluentes externos, melhorando o desempenho da ETE. / In Brazil, only a small portion of domestic wastewater collected is effectively treated. In most cities, the treatment system used is the septage, which have low efficiency and need for maintenance and periodic removal of sludge, which must be properly disposed. In the cities there is the generation of other types of waste such as sludge from septage, in this case considered an effluent as the water content exceeds 90%, effluent from chemical toilet and sanitary landfill leachate, all generated from urban activities, and require adequate treatment to final disposal. The combined treatment of these external effluents with domestic wastewater has been used as a strategy to reduce the cost of tractability. However, the great variability of composition and concentration of this effluents, make it a difficult treatability mixture, especially on conventional plants. There is still no consensus on the impacts caused by this mixture of effluents on the degradation processes commonly found in DWTPs nor on the safe ratio for the dilution to be adopted in regard to domestic wastewater. DWTP Canoas - CORSAN has an activated sludge system operating in batch, there is the combined treatment of domestic wastewater, sludge from septage, effluent from chemical toilet and sanitary landfill leachate, without a maximum amount stipulated for receipt of these external effluent. This study aimed to characterize the influent mixture and assess the impact of combined treatment on the operating conditions of the DWTP, as well as its performance in the removal of organics and nutrients between January 2009 to August 2010. It was found that the percentage of dilution of external effluent in domestic wastewater varied between 2.1% and 11.3% and that the contribution of this effluents to the total COD load varied between 14% and 74%. The physico-chemical composition of the influent mixture to biological reactor has influence on the composition of the microfauna present in the SBR. The most frequently observed impact by the shock loads entry was the loss of biomass due to flocculation and settling problems, such as bulking. The occurrence of shock loads due to the entry of external effluents promoted an increase in the SVL of 46 mL/g to 287 mL/g, just as there was an increase in the F/M, which increased from 0.42 d-¹ to 0.82 d-¹. Among the metals analyzed for Ca, Fe and K were found in higher percentages in the external effluent samples, corresponding to 15.8%, 10.4% and 10.1% respectively. Were also detected for Cu, Zn, Ti, Cr, in low percentages. In biological sludge were detected 56% Fe, 16% Ca, 10% Si and 8% of S, adsorbed on the flocs, and Zn (4%), Cu (3%), Mn (1.5%) and K (1.2%). The frequent exposure of activated slugde community to shock loads was the main effect to collaborate in the removal efficiencies reduction of TSS, BOD5, COD, TP and N-NH4 +, damaging the quality of the final effluent. The adoption of a unit for receiving and preliminary treatment of external effluents could permit a greater operational control in the receiving and treatment dynamic of external effluents, improving the performance of DWTP.
93

Suivi et devenir des organoétains dans des lixiviats de décharge / Investigations of the fate of organotin compounds in landfill leachates

Peeters, Kelly 20 April 2015 (has links)
Les organoétains sont parmi les polluants les plus dangereux connus à ce jour à avoir été introduits dans les écosystèmes aquatiques par l'homme. Les lixiviats de décharge sont des sources importantes de ces substances toxiques. Afin de minimiser leur rejet dans l'environnement, il est important de comprendre les transformations que les organoétains subissent dans ces lixiviats et d'appliquer des procédures d'assainissement appropriées. Cette thèse a eu pour objectifs principaux i) de contribuer à une meilleure connaissance des processus de transformation des organoétains dans les lixiviats de décharge et ii) d'évaluer le potentiel d’élimination des organoétains par des nanaoparticules de fer (FeNPs). Dans la première partie, les synthèses de TBT enrichi en 117Sn, DBT enrichi en 119Sn, SnCl2 et SnCl4 enrichi en 117Sn, ont été effectuées à partir d’étain métallique enrichi en Sn. La dégradation et la biométhylation des organoétains dans des lixiviats ont été ensuite suivies pendant six mois, en utilisant des traceurs isotopiques enrichis en Sn. Pour discriminer entre les transformations biotiques et abiotiques des organoétains et de l'étain inorganique, des lixiviats stérilisés et non stérilisés ont été considérés et les concentrations en organoétains, mesurées dans chaque lixiviat, ont été comparées. Par la suite, les procédés pouvant conduire à l'élimination du TBT et du TMeT présents dans les lixiviats de décharge, par traitement du lixiviat par différents type de FeNPs ont été étudiés. Le TBT est plus efficacement éliminé (96%) lorsque un traitement séquentiel des lixiviats avec nZVI (dispersé par agitation) est appliqué, d'abord par mise en contact à pH 8, puis par traitement de la phase aqueuse avec nZVI acidifiée à pH 3 avec de l'acide citrique. Enfin, afin de prendre en compte les effets induits par les procédés de traitement par les nanoparticules de fer, leur comportement a été étudié après leur introduction dans des eaux environnementales (eau de source et lixiviat de décharge) différant par leur force ionique et leur contenu de matière organique. L'efficacité de l'élimination des métaux sélectionnés par les FeNPs a également été évaluée. Les nanoparticules ayant des éléments adsorbés à leur surface peuvent contribuer à une contamination du milieu dans lequel elles ont été introduites. / OTCs are among the most hazardous pollutants known so far to have ever been introduced into aquatic ecosystems by man. Landfill leachates are an important pool of these toxic substances. In order to minimise their release to the nearby environment it is important to understand the transformations that OTCs undergo in landfill leachates and to apply appropriate remediation procedures. This thesis has as main objectives i) to contribute to a better knowledge on transformation processes of OTCs in landfill leachates and ii) to evaluate the potential of OTCs removal by iron nanoparticles (FeNPs). In the first part, ‘‘In house’’ synthesis of individual 117Sn-enriched TBT, 119Sn-enriched DBT, 117Sn-enriched SnCl2 and 117Sn-enriched SnCl4 was performed, starting from Sn-enriched metallic tin. Next, the degradation and biomethylation of OTCs in landfill leachates were investigated over a time span of six months, using Sn-enriched isotopic tracers. To discriminate between biotic and abiotic transformations of OTCs and inorganic tin species, sterilized and non-sterilized leachate samples were investigated and the concentrations of OTCs in each sample were compared. Thereafter, the processes for the removal of TBT and TMeT from landfill leachates by different FeNPs were studied. It was proven that TBT could be the best removed by a sequential treatment procedure by first adding nZVI (dispersed by mixing) at pH 8, and then by treating with nZVI the aqueous phase, which is acidified to pH 3 with citric acid. Last, to take in account the effects that are induced by treatment procedures with FeNPs, their behaviour was studied after their introduction to environmental waters (forest spring water and landfill leachate), which differ in their ionic strength and the content of organic matter. The efficiency of the removal of selected metals by FeNPs was also evaluated. It was observed that elements which are adsorbed on the surface of FeNPs can contribute to the contamination of the environment in which they are introduced.
94

Typhas inverkan på reningsgraden av TKN, BOD5 och COD i en anlagd rotzonsvåtmark i pilotskala. / Study of vegetation effects in a constructed wetland for landfill leachate. (Sanitário de Lajeado - RS)

Lind, Linus January 2010 (has links)
<p>Detta examensarbete är utfört på plats i Lajaedo, Brasilien och i anslutning till Sanitário de Lajeado – RS, Brasilien, mellan januari till maj 2010. I samband med denna rapport utfördes två andra examensarbeten inom samma områden. Det är menat att denna rapport skall ligga till grund för framtida projekt och beslut om utökad lakvattenrening.Lajeado ligger i södra Brasilien ca 100 km från atlantkusten. 10 km utanför Lajeado ligger en ung avfallsdeponi på ca 15 000 m2 till ytan med tillhörande lakvattenrening med ett utjämningsmagasin, en syrsättningsbassäng samt sedimentering. Deponin tar emot 42 ton fast kommunalt avfall per dag och har ett lakvattenflöde på genomsnitt 0,5 – 1,0 m3/h.Syftet med denna rapport är att undersöka vilken inverkan vegetation har på reningen av lakvatten inom parametrarna TKN, BOD5 och COD, i småskaliga våtmarker av typen rotzonsanläggning. Då den befintliga reningen på plats har svårt att uppfylla vissa uppsatta lagkrav.Sammansättningen på och mängden av lakvatten beror främst på faktorerna, nederbörd, Temperatur och nedbrytningen i deponin.Vegetationens har många olika betydelser i en rotzonsanläggning. Plantan transporter ner syre till dess rotsystem där syremolekyler diffunderar ut. Vegetation fungerar även som en extern kolkälla vid denitrifikationsteget. Det är viktigt att vegetationen trivs och rotsystemet är välutvecklat, för att få en maximal reduktion av föroreningar i våtmarken.Åtta småskaliga våtmarker byggdes upp i anslutning till lakvattenreningen, i avkapade plasttunnor. Alla våtmarker byggdes upp med unika förutsättningar för att kunna jämföra resultatet. Två olika substrat användes och jämfördes, i fyra kar planterades vegetation och fyra utan, fyra hade kontinuerligt flöde som jämfördes med fyra kar med batch flow.Resultaten visar att växterna inte har någon större inverkan på reningsgraden av BOD5, COD och TKN. Men såg tydliga tecken på högre vattenavdunstning i våtmarkerna med biomassa och generellt högre halter av BOD5, COD och TKN i jämförelse med våtmarkerna utan biomassa. Vegetationen hann inte acklimatisera sig till miljön i våtmarkerna, men det var på god väg. För att få ett bättre resultat och en mer signifikant skillnad mellan våtmarkerna skulle försöken ha pågått under en längre tid. Det behövs mer forskning och projekt under en längre period.Detta examensarbete är utfört på plats i Lajaedo, Brasilien och i anslutning till Sanitário de Lajeado – RS, Brasilien, mellan januari till maj 2010. I samband med denna rapport utfördes två andra examensarbeten inom samma områden. Det är menat att denna rapport skall ligga till grund för framtida projekt och beslut om utökad lakvattenrening.Lajeado ligger i södra Brasilien ca 100 km från atlantkusten. 10 km utanför Lajeado ligger en ung avfallsdeponi på ca 15 000 m2 till ytan med tillhörande lakvattenrening med ett utjämningsmagasin, en syrsättningsbassäng samt sedimentering. Deponin tar emot 42 ton fast kommunalt avfall per dag och har ett lakvattenflöde på genomsnitt 0,5 – 1,0 m3/h.Syftet med denna rapport är att undersöka vilken inverkan vegetation har på reningen av lakvatten inom parametrarna TKN, BOD5 och COD, i småskaliga våtmarker av typen rotzonsanläggning. Då den befintliga reningen på plats har svårt att uppfylla vissa uppsatta lagkrav.Sammansättningen på och mängden av lakvatten beror främst på faktorerna, nederbörd, Temperatur och nedbrytningen i deponin.Vegetationens har många olika betydelser i en rotzonsanläggning. Plantan transporter ner syre till dess rotsystem där syremolekyler diffunderar ut. Vegetation fungerar även som en extern kolkälla vid denitrifikationsteget. Det är viktigt att vegetationen trivs och rotsystemet är välutvecklat, för att få en maximal reduktion av föroreningar i våtmarken.Åtta småskaliga våtmarker byggdes upp i anslutning till lakvattenreningen, i avkapade plasttunnor. Alla våtmarker byggdes upp med unika förutsättningar för att kunna jämföra resultatet. Två olika substrat användes och jämfördes, i fyra kar planterades vegetation och fyra utan, fyra hade kontinuerligt flöde som jämfördes med fyra kar med batch flow.Resultaten visar att växterna inte har någon större inverkan på reningsgraden av BOD5, COD och TKN. Men såg tydliga tecken på högre vattenavdunstning i våtmarkerna med biomassa och generellt högre halter av BOD5, COD och TKN i jämförelse med våtmarkerna utan biomassa. Vegetationen hann inte acklimatisera sig till miljön i våtmarkerna, men det var på god väg. För att få ett bättre resultat och en mer signifikant skillnad mellan våtmarkerna skulle försöken ha pågått under en längre tid. Det behövs mer forskning och projekt under en längre period.</p> / <p>The ability for a subsurface flow constructed wetland system to treat landfill leachate was evaluated in Lajeado, Rio Grande do Sul, Brazil. Eight 0.95 m x 0.6 m experimental (SSF) units with a depth 0.4 m were used. Each wetland had unique conditions. Four units were planted with Typha angustifolia L. and four units were unplanted. Two different substrate dimension were used, four units with sand and four with gravel. Four wetlands operated in batch mode and four units with continuous flow. Batch flow systems were drained and filled up each week. To review vegetations impact on BOD5, COD and nitrogen compounds reduced in a wetland. This project lasted between January until May 2010 and samples were analyzed in April to May in four weeks.The result from this project show higher evapotranspiration water loss in units with planted vegetation and higher effluents concentration of BOD5, COD and nitrogen compounds, than in unplanted units.The ability for a subsurface flow constructed wetland system to treat landfill leachate was evaluated in Lajeado, Rio Grande do Sul, Brazil. Eight 0.95 m x 0.6 m experimental (SSF) units with a depth 0.4 m were used. Each wetland had unique conditions. Four units were planted with Typha angustifolia L. and four units were unplanted. Two different substrate dimension were used, four units with sand and four with gravel. Four wetlands operated in batch mode and four units with continuous flow. Batch flow systems were drained and filled up each week. To review vegetations impact on BOD5, COD and nitrogen compounds reduced in a wetland. This project lasted between January until May 2010 and samples were analyzed in April to May in four weeks.The result from this project show higher evapotranspiration water loss in units with planted vegetation and higher effluents concentration of BOD5, COD and nitrogen compounds, than in unplanted units.</p>
95

Typhas inverkan på reningsgraden av TKN, BOD5 och COD i en anlagd rotzonsvåtmark i pilotskala. / Study of vegetation effects in a constructed wetland for landfill leachate. (Sanitário de Lajeado - RS)

Lind, Linus January 2010 (has links)
Detta examensarbete är utfört på plats i Lajaedo, Brasilien och i anslutning till Sanitário de Lajeado – RS, Brasilien, mellan januari till maj 2010. I samband med denna rapport utfördes två andra examensarbeten inom samma områden. Det är menat att denna rapport skall ligga till grund för framtida projekt och beslut om utökad lakvattenrening.Lajeado ligger i södra Brasilien ca 100 km från atlantkusten. 10 km utanför Lajeado ligger en ung avfallsdeponi på ca 15 000 m2 till ytan med tillhörande lakvattenrening med ett utjämningsmagasin, en syrsättningsbassäng samt sedimentering. Deponin tar emot 42 ton fast kommunalt avfall per dag och har ett lakvattenflöde på genomsnitt 0,5 – 1,0 m3/h.Syftet med denna rapport är att undersöka vilken inverkan vegetation har på reningen av lakvatten inom parametrarna TKN, BOD5 och COD, i småskaliga våtmarker av typen rotzonsanläggning. Då den befintliga reningen på plats har svårt att uppfylla vissa uppsatta lagkrav.Sammansättningen på och mängden av lakvatten beror främst på faktorerna, nederbörd, Temperatur och nedbrytningen i deponin.Vegetationens har många olika betydelser i en rotzonsanläggning. Plantan transporter ner syre till dess rotsystem där syremolekyler diffunderar ut. Vegetation fungerar även som en extern kolkälla vid denitrifikationsteget. Det är viktigt att vegetationen trivs och rotsystemet är välutvecklat, för att få en maximal reduktion av föroreningar i våtmarken.Åtta småskaliga våtmarker byggdes upp i anslutning till lakvattenreningen, i avkapade plasttunnor. Alla våtmarker byggdes upp med unika förutsättningar för att kunna jämföra resultatet. Två olika substrat användes och jämfördes, i fyra kar planterades vegetation och fyra utan, fyra hade kontinuerligt flöde som jämfördes med fyra kar med batch flow.Resultaten visar att växterna inte har någon större inverkan på reningsgraden av BOD5, COD och TKN. Men såg tydliga tecken på högre vattenavdunstning i våtmarkerna med biomassa och generellt högre halter av BOD5, COD och TKN i jämförelse med våtmarkerna utan biomassa. Vegetationen hann inte acklimatisera sig till miljön i våtmarkerna, men det var på god väg. För att få ett bättre resultat och en mer signifikant skillnad mellan våtmarkerna skulle försöken ha pågått under en längre tid. Det behövs mer forskning och projekt under en längre period.Detta examensarbete är utfört på plats i Lajaedo, Brasilien och i anslutning till Sanitário de Lajeado – RS, Brasilien, mellan januari till maj 2010. I samband med denna rapport utfördes två andra examensarbeten inom samma områden. Det är menat att denna rapport skall ligga till grund för framtida projekt och beslut om utökad lakvattenrening.Lajeado ligger i södra Brasilien ca 100 km från atlantkusten. 10 km utanför Lajeado ligger en ung avfallsdeponi på ca 15 000 m2 till ytan med tillhörande lakvattenrening med ett utjämningsmagasin, en syrsättningsbassäng samt sedimentering. Deponin tar emot 42 ton fast kommunalt avfall per dag och har ett lakvattenflöde på genomsnitt 0,5 – 1,0 m3/h.Syftet med denna rapport är att undersöka vilken inverkan vegetation har på reningen av lakvatten inom parametrarna TKN, BOD5 och COD, i småskaliga våtmarker av typen rotzonsanläggning. Då den befintliga reningen på plats har svårt att uppfylla vissa uppsatta lagkrav.Sammansättningen på och mängden av lakvatten beror främst på faktorerna, nederbörd, Temperatur och nedbrytningen i deponin.Vegetationens har många olika betydelser i en rotzonsanläggning. Plantan transporter ner syre till dess rotsystem där syremolekyler diffunderar ut. Vegetation fungerar även som en extern kolkälla vid denitrifikationsteget. Det är viktigt att vegetationen trivs och rotsystemet är välutvecklat, för att få en maximal reduktion av föroreningar i våtmarken.Åtta småskaliga våtmarker byggdes upp i anslutning till lakvattenreningen, i avkapade plasttunnor. Alla våtmarker byggdes upp med unika förutsättningar för att kunna jämföra resultatet. Två olika substrat användes och jämfördes, i fyra kar planterades vegetation och fyra utan, fyra hade kontinuerligt flöde som jämfördes med fyra kar med batch flow.Resultaten visar att växterna inte har någon större inverkan på reningsgraden av BOD5, COD och TKN. Men såg tydliga tecken på högre vattenavdunstning i våtmarkerna med biomassa och generellt högre halter av BOD5, COD och TKN i jämförelse med våtmarkerna utan biomassa. Vegetationen hann inte acklimatisera sig till miljön i våtmarkerna, men det var på god väg. För att få ett bättre resultat och en mer signifikant skillnad mellan våtmarkerna skulle försöken ha pågått under en längre tid. Det behövs mer forskning och projekt under en längre period. / The ability for a subsurface flow constructed wetland system to treat landfill leachate was evaluated in Lajeado, Rio Grande do Sul, Brazil. Eight 0.95 m x 0.6 m experimental (SSF) units with a depth 0.4 m were used. Each wetland had unique conditions. Four units were planted with Typha angustifolia L. and four units were unplanted. Two different substrate dimension were used, four units with sand and four with gravel. Four wetlands operated in batch mode and four units with continuous flow. Batch flow systems were drained and filled up each week. To review vegetations impact on BOD5, COD and nitrogen compounds reduced in a wetland. This project lasted between January until May 2010 and samples were analyzed in April to May in four weeks.The result from this project show higher evapotranspiration water loss in units with planted vegetation and higher effluents concentration of BOD5, COD and nitrogen compounds, than in unplanted units.The ability for a subsurface flow constructed wetland system to treat landfill leachate was evaluated in Lajeado, Rio Grande do Sul, Brazil. Eight 0.95 m x 0.6 m experimental (SSF) units with a depth 0.4 m were used. Each wetland had unique conditions. Four units were planted with Typha angustifolia L. and four units were unplanted. Two different substrate dimension were used, four units with sand and four with gravel. Four wetlands operated in batch mode and four units with continuous flow. Batch flow systems were drained and filled up each week. To review vegetations impact on BOD5, COD and nitrogen compounds reduced in a wetland. This project lasted between January until May 2010 and samples were analyzed in April to May in four weeks.The result from this project show higher evapotranspiration water loss in units with planted vegetation and higher effluents concentration of BOD5, COD and nitrogen compounds, than in unplanted units.
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Estudo da tratabilidade do lixiviado de aterro sanitário pelos processos oxidativos avançados foto-Fenton, ozônio e ozônio combinado com peróxido de hidrogênio / Study of treatability of landfill leachate by advanced oxidation processes photo-Fenton, ozone and ozone combined with hydrogen peroxide

Luciano do Valle Monteiro 05 June 2012 (has links)
O lixiviado de aterro sanitário possui constituição complexa e é altamente poluente. Neste contexto, os processos oxidativos avançados se destacam como pré-tratamento, objetivando a remoção ou diminuição da recalcitrância do lixiviado. Neste trabalho foram utilizados os Processos Oxidativos Avançados (POAs) foto-Fenton, ozônio e ozônio combinado com peróxido de hidrogênio. Avaliou-se a influência do pré-tratamento por air-stripping, a variação na produção de ozônio em 80 e 100%, a melhor dose de peróxido de hidrogênio correspondente a 20, 40 e 80% da dose de 6g O3/L empregada nos tratamentos com ozônio, a remoção de matéria orgânica, nitrogênio amoniacal total (NAT), alcalinidade, sólidos dissolvidos totais (SDT) (cloretos), produção de nitrito e nitrato, melhor razão molar [H2O2]/[Fe2+] para o tempo de contato de 80 min no foto-Fenton, uso do número médio de oxidação do carbono (NMOC) e a quantificação do ácido oxálico formado após a aplicação dos POAs. O tratamento por O3/H2O2 (1,2 g H2O2/L e produção de O3 em 80%) obteve a maior remoção de matéria orgânica, 0,14 g massa removida de Carbono Orgânico Total (COT) / massa consumida de O3 e 0,43 g/g para a Demanda Química de Oxigênio (DQO). Quanto ao foto-Fenton, averiguou-se o máximo de 74% remoção de COT e 65% remoção DQO para a razão molar [H2O2]/[Fe2+] igual a 2. Também se notou formação de sólidos sedimentáveis neste processo aplicado ao lixiviado bruto. O pré-tratamento por air-stripping não promoveu incremento na remoção de matéria orgânica. As concentrações de NAT, alcalinidade, SDT (cloretos) se mantiveram elevadas após a aplicação dos POA. Ocorreu formação de nitrato em todos os tratamentos. O uso do NMOC foi adequado e demonstrou ocorrência de oxidação nos processos. A quantificação do ácido oxálico formado após a aplicação dos POAs não foi apropriada nesta pesquisa. / The landfill leachate is a major waste produced by the landfill and its constitution complex and highly polluting motivate research in order to adapt their disposal on the environment. In this context, the advanced oxidation processes stand out as a pretreatment, in order to remove or decrease the recalcitrance of the leachate. In this work we used the photo-Fenton AOPs, ozone and ozone combined with hydrogen peroxide. We evaluated the effect of pretreatment for air-stripping, the variation in the production of ozone 80 and 100%, the best dose of hydrogen peroxide equal to 20, 40 and 80% of the dose of 6g O3/ L used in the treatments with ozone, the removal of organic matter, total ammonia nitrogen, alkalinity, dissolved solids (chlorides), production of nitrite and nitrate, best molar ratio [H2O2]/[Fe2+] to the contact time of 80 min in the photo-Fenton, average number of carbon oxidation use and the measurement of oxalic acid formed after application of the AOPs. The AOP O3/H2O2 (1.2g H2O2/L and O3 production by 80%) had the highest removal of organic matter, 0.14 g of TOC removed mass/ mass consumed O3 and 0.43 g/g for COD. As for the photo-Fenton, it was found a maximum of 74% removal of TOC and 65% for COD removal molar ratio [H2O2]/[Fe2+] equal to 2. It was also noted the formation of settle able solids in the process applied to the raw leachate. Pretreatment by air-stripping did not promote an increase in organic matter removal. Total ammonia nitrogen concentrations, alkalinity, dissolved solids (chlorides) remained high after application of the AOP, indicating possible oxidant demand. For nitrate formation occurred in all treatments, while only the photo-Fenton was no formation of nitrite. The use of average number of carbon oxidation was adequate and showed occurrence of oxidation processes. The quantification of oxalic acid formed after the application of AOPs was not appropriate in this research.
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Sistema de filtração lenta no tratamento de percolado do aterro sanitario de Limeira-SP / Slow sand filter in the treatment of leachate of the sanitary landfill of Limeira -SP

Pelegrini, Nubia Natalia de Brito 17 February 2006 (has links)
Orientador: Jose Euclides Stipp Paterniani / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Agricola / Made available in DSpace on 2018-08-06T12:32:37Z (GMT). No. of bitstreams: 1 Pelegrini_NubiaNataliadeBrito_M.pdf: 1010430 bytes, checksum: 1a5af5bc021dbf527427add6944a6e6d (MD5) Previous issue date: 2006 / Resumo: A disposição final de resíduos sólidos é uma prática que ainda traz sérios impactos ao meio ambiente. Nos aterros sanitários, os resíduos passam por processos físicos, químicos e biológicos de decomposição, gerando uma fração gasosa (composta principalmente por gases dióxido de carbono e metano) e uma fase líquida conhecida como chorume (ou percolado de aterro sanitário). O chorume de lixo é um líquido com elevado potencial poluente, os métodos convencionais utilizados em seu tratamento têm descartado-o com intensa coloração e alta toxicidade. Este trabalho teve como objetivo implantar em escala piloto um sistema de filtração lenta precedido de uma pré-filtração, apenas em manta sintética não tecida, para o tratamento de chorume de lixo ¿in natura¿, proveniente do aterro sanitário da cidade de Limeira-SP. O filtro lento foi constituído por um tanque cilíndrico de plástico tendo como meio filtrante areia e mantas sintéticas não tecidas. A taxa de filtração adotada durante os experimentos foi de 3 m3/m2.dia. O sistema de tratamento em estudo apresentou reduções consideráveis dos valores de alguns parâmetros de controle ambiental indicando a possibilidade do uso da filtração lenta para remediação de águas residuárias. As principais reduções obtidas referem-se a 40% de turbidez, 21% da coloração, 35% de dureza, 35% de carbono orgânico total (TOC) e reduções consideráveis de metais pesados (60% de cádmio, 30% de chumbo, 25% de cobre e 30% de cromo). Com relação à reutilização do chorume tratado em atividades agrícolas ainda são necessárias maiores reduções dos valores de parâmetros analíticos através da complementação com outras tecnologias de tratamento / Abstract: The final disposition of solids residues is a practice that still brings serious impacts to the environment. In sanitary landfill, the residues goes through physical, chemical and biological decomposition processes, generating into a gas phase (mainly composed by CH4 and CO2) and a liquid phase known as leachate. The waste leachate is a liquid with high pollutant potential. The conventional methods used in the treatment this residue have discarded him with intense coloration and high toxicity. This work had as objective implant in pilot scale a system of slow sand filtration preceded of a pré-filtration, only in non-woven synthetic fabrics, for the waste leachate treatment in natura, originating from the sanitary landfill of the city of Limeira-SP. The slow sand filter is constituted by a plastic cylindrical tank, sands and non-woven synthetic fabrics. The filtration rate adopted during the experiments it was of 3 m3/m2.dia. The treatment system in study presented considerable reductions of some values of environmental parameters control indicating the possibility of the use of the slow filtration for remediação of wastewaters. The main obtained reductions were 40% of turbidity, 21% of color, 35% of hardness, 35% of total organic carbon (TOC) and reductions considerably of heavy metals (60% of cadmium, 30% of lead, 25% of cupper and 30% of chrome). For the reuse of the treated leachate in agricultural activities are necessary larger reductions of some values of analytic parameters through the complementation with other treatment technologies. eywords: Landfill Leachate, Sanitary Landfill, Slow Sand Filtration, Reuse / Mestrado / Agua e Solo / Mestre em Engenharia Agrícola
98

Oxydation par voie humide catalytique d’effluents industriels : catalyseurs métaux nobles supportés / Catalytic wet air oxidation of industrial wastes : noble metal supported catalysts

Grosjean, Nicolas 18 February 2010 (has links)
L’industrie produit de grandes quantités d’effluents aqueux qu’il convient de traiter. Des traitements alternatifs aux procédés biologiques doivent être développés pour certains effluents toxiques et/ou non biodégradables. L’oxydation en voie humide catalytique repose sur l’action de l’oxygène sur les polluants en phase aqueuse à haute température et haute pression. Préalablement à cette étude, des catalyseurs au Ru ou Pt supportés sur ZrO2 ou TiO2très actifs et très stables pour l’OVHC de polluants modèles et de quelques effluents réels ont été développés. Ce travail a examiné ces catalyseurs sur d’autres effluents réels : un effluent provenant d’une unité de production de membranes contenant du glycérol et du DMF, uneffluent de sauce de couchage provenant de l’industrie papetière et un concentrât de lixiviatde décharge. Les catalyseurs se sont révélés très actifs et stables pour la minéralisation du glycérol, mais une forte lixiviation a été observée lors de l’OVHC du DMF du fait de la présence d’amines. L’oxydation de l’effluent de sauce de couchage permet de minéraliser la charge organique, facilitant le recyclage de la charge minérale, avec une amélioration accrue de la biodégradabilité du surnageant en présence des catalyseurs. Enfin, l’ajout de catalyseurs lors de l’OVH du concentrât de lixiviat de décharge permet d’améliorer sa minéralisation et d’éliminer totalement les ions ammonium / Industries produce huge volumes of effluents which need to be treated before disposal.Alternative treatments to the more classical biological techniques are required in the case oftoxic and/or non biodegradable effluents. The wet air oxidation (WAO) and catalytic wet airoxidation (CWAO) are based on the reaction of an oxidant (oxygen) with the pollutants in aqueous phase at high temperature and pressure. Ru or Pt catalysts supported on zirconium and titanium oxides were previously shown to be highly active and stable in the CWAO of awide range of model compounds and real complex effluents. These catalysts were evaluated in the CWAO of problematic effluents: one containing glycerol and DMF, one paper coatingslip effluent and one concentrated landfill leachate. The catalysts showed high activity and stability in the CWAO of glycerol, while the metal leached upon DMF CWAO due to the presence of amines. WAO leads to the partial mineralization of the organic load in paper coating slip, allowing an easy separation recycling of mineral pigments, with an improved biodegradability of the supernatant with the use of a catalyst. The use of a catalyst upon landfill leachate WAO leads higher COT conversion and complete ammonia elimination
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Tratamento de lixiviados de aterros sanitários em sistema de reatores anaeróbio e aeróbio operados em batelada seqüencial / Landfill leachate treatment in sequence anaerobic and aerobic batch reactors systems

Contrera, Ronan Cleber 06 June 2008 (has links)
Este trabalho avaliou a tratabilidade dos lixiviados do aterro sanitário de São Carlos-SP, utilizando-se reatores biológicos. O experimento foi conduzido à temperatura ambiente, em uma unidade piloto construída no aterro sanitário de São Carlos-SP. Inicialmente foram testados e comparados dois tipos de reatores anaeróbios, cada um com volume total de 1.200 L e ambos providos de agitação mecânica, diferenciando-se pelo tipo de imobilização da biomassa, sendo o primeiro com biomassa auto-imobilizada (ASBR) e o segundo com biomassa imobilizada em espuma de poliuretano (ASBBR). Um filtro biológico anaeróbio contínuo de fluxo ascendente de aproximadamente 120 L também foi avaliado. Além do pré-tratamento anaeróbio, foi avaliado também o pós-tratamento, que consistiu em um sistema de lodos ativados em batelada seqüencial de aproximadamente 180 L. O ASBR, inoculado com lodo granular de reator UASB, apresentou-se ineficiente, com problemas de desagregação e sedimentação da biomassa. O ASBBR, inoculado com lodo proveniente do fundo de uma lagoa de lixiviados, ao final de sua adaptação, apresentou eficiências superiores a 70%, em termos de remoção de DQO, utilizando-se lixiviado sem diluição, com DQO afluente da ordem de 11.000 mg/L, relação AVT/DQO aproximadamente igual a 0,6 e tempo de reação igual a 7 dias. Verificou-se que a biodegradabilidade anaeróbia dos lixiviados está diretamente relacionada à relação AVT/DQO, e que para relações AVT/DQO Total inferiores a 0,25, a biodegradabilidade é baixa, para relações entre 0,25 e 0,40 é média, e acima de 0,40 pode ser considerada elevada. Observou-se também que concentrações de N-amoniacal, da ordem de até 4.500 mg/L, não impedem o tratamento anaeróbio, desde que a biomassa esteja devidamente adaptada. Aos perfis temporais de concentração, realizados no ASBBR, foi ajustado um modelo de primeira ordem para consumo de substrato, na forma de DQO Total, obtendo valores de K1 variando entre 3,18 x \'10 POT.-5\' e 5,82 x \'10 POT.-5\' /(d.mgSTV/L). O pós-tratamento dos efluentes do ASBBR foi avaliado em um sistema de lodos ativados em batelada seqüencial, que obteve eficiência máxima da ordem de 30% em termos de remoção de DQO, com DQO afluente da ordem de 5.000 mg/L. Quanto ao filtro biológico anaeróbio de fluxo ascendente, obteve-se eficiências superiores a 70%, ao ser alimentado com uma mistura de lixiviado recalcitrante e etanol acidificado, com DQO afluente da ordem de 20.000 mg/L. / This work evaluated the tractability of landfill leachate from São Carlos-SP, utilizing biological reactors. The experiment was conducted at environmental temperature, in a pilot scale unity constructed into the São Carlos-SP landfill area. Initially, it was compared and tested two kinds of anaerobic reactors, each one with 1.200 L of total volume and both provided of mechanical agitation, differing by the kind of biomass immobilization, having the first (ASBR), self-immobilized biomass, and the second (ASBBR), immobilized biomass in polyurethane foam cubes. An approximately 120 L volume continuous up flow anaerobic biofilter was also evaluated. Additionally to the anaerobic treatment, it was also evaluated the post-treatment of landfill leachate in a sequence batch activated sludge system of 180 L. The ASBR, inoculated with a granular UASB sludge from a poultry wastewater treatment, was inefficient and presented sludge segregation and sedimentation problems. The ASBBR, inoculated using the sludge from the bottom of a landfill leachate reservoir, at the final of acclimation, presented efficiency over 70%, in terms of COD removal, utilizing landfill leachate without water dilution, with an inlet COD at the range of 11,000 mg/L, a TVA/COD ratio of approximately 0.6 and reaction time equal to 7 days. It was realized that the landfill leachate anaerobic biodegradability has a directly relationship to the TVA/COD ratio, and for TVA/COD Total ratio lower than 0.25, the biodegradability is low, for ratios between 0.25 and 0.40 is medium, and up to 0.40 may be considered high. It was also observed that \'NH IND.4\' POT.+\' concentrations at the range of 4,500 mg N/L has no significant interference in the anaerobic treatment, since the biomass has properly acclimated. At the temporal profiles of concentration performed in the ASBBR, it was adjusted a first order model for the substrate consumption, in terms of COD Total, obtaining K1 values ranging between 3.18 x \'10 POT.-5\' and 5.82 x \'10 POT.-5\' /(d.mgSTV/L). The post-treatment of the ASBBR effluents was evaluated in a sequence batch activated sludge system, which has obtained maximum efficiencies at the range of 30% in terms of COD removal, with an inlet COD at the range of 5,000 mg/L. As regards of the continuous up flow anaerobic biofilter, it has obtained efficiencies superiors to 70% when fed by a mixing of recovery landfill leachate and acidified ethanol, with an inlet COD at the range of 20,000 mg/L.
100

Evaluation of the Engineering Properties of Municipal Solid Waste for Landfill Design

Lakshmikanthan, P January 2015 (has links) (PDF)
The objective of this thesis is to evaluate the engineering properties of Municipal Solid Waste (MSW) that are necessary in the design of landfills. The engineering properties of MSW such as compressibility, shear strength, stiffness and hydraulic conductivity are crucial in design and construction of landfills. The variation of the engineering properties with time, age and degradation are of paramount importance in the field of landfill engineering. There is a need to address the role of the engineering properties in landfill engineering as it is not apparent how the engineering characteristics vary with time. The thesis presents the results of study of the engineering properties of MSW comprehensively and develops experimental data for design of MSW landfills. The work includes the study of the index properties and the engineering properties of MSW such as compressibility, shear strength, shear modulus and damping ratio and a detailed experimental study of the bioreactor landfill. The components of settlements, variation of shear strength with respect to unit weight and particle size are determined experimentally and analyzed. The dynamic properties such as shear modulus and material damping ratio and its variation with parameters such as unit weight, load, amplitude, degradation and moisture content are studied and analyzed. The normalized shear modulus reduction curve which is used in the seismic analysis of the landfills is developed for MSW based on the experimental results and previous studies. A pilot-scale bioreactor was setup in the laboratory for long term monitoring of the settlement, temperature variation and gas production simultaneously. The parameters of interest viz, pH, BOD, COD, conductivity, alkalinity, methane and carbon-di-oxide were determined. The generated data can be effectively used in the engineered design of landfills. For a better understanding, the present thesis is divided into the following eight chapter Chapter 1 provides a general introduction to the thesis with respect to the importance of engineering properties of MSW and presents the organization of the thesis. Chapter 2 presents a detailed review of literature pertaining to the basic, index and the engineering properties of MSW namely compressibility, shear strength, shear modulus and damping ratio, bioreactor landfill and also the scope of the study. Chapter 3 includes the materials and methods followed in the thesis. Chapter 4 presents the evaluation of compressibility characteristics of MSW including the components of settlement and the settlement model parameters. Chapter 5 presents the determination of the shear strength properties of MSW using direct shear tests and triaxial tests. The variation of the strength with respect to unit weight and the particle size is examined. The results are examined in terms of strength ratio and stiffness ratio and the implications are discussed. Chapter 6 presents the study of the dynamic characters of MSW. The variation of the shear modulus and damping ratio with respect to unit weight, confining pressure, loading frequency, decomposition and moisture content are analyzed. Normalized shear modulus reduction and damping curves are proposed for seismic analysis. Chapter 7 presents the study of the conventional and the bioreactor landfill in a small scale laboratory setup. A large scale experimental setup is fabricated to study the characteristics of a bioreactor landfill and includes the long term monitoring and analysis of temperature, gas, settlement and leachate characteristics periodically. The results of the comprehensive study are presented in this chapter. Chapter 8 summarizes the important conclusions from the various experimental studies reported in this dissertation. Conclusions and the scope of future work are presented. A detailed list of references and the list of publications from the thesis are presented at the end. Appendix A presents the life cycle analysis and life cycle cost analysis of MSW land disposal options. The land disposal options such as open dumps, engineered landfills and bioreactor landfills are analyzed in this study.

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