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

Tratamento de lixiviado de aterro sanitário por um sistema composto por filtros anaeróbios seguidos de banhados construídos: estudo de caso - Central de Resíduos do Recreio, em Minas do Leão/RS / Sanitary landfill leachate treatment for a system composed by upflow anaerobic filters followed by constructed wetlands: case study - Recreio Central Waste, in Minas do Leão/RS

Bidone, Ricardo Figueira 03 March 2008 (has links)
A presente pesquisa abordou o estudo em escala real do tratamento de lixiviado de aterro sanitário em um sistema composto por dois filtros anaeróbios seguidos de dois banhados construídos. O trabalho foi desenvolvido na estação de tratamento de lixiviado do aterro sanitário pertencente à Central de Resíduos do Recreio, localizada em Minas do Leão/RS. Pretendeu-se verificar a eficiência do sistema na remoção de matéria orgânica e de nitrogênio amoniacal. A fase 1 da pesquisa, que avaliou o desempenho dos filtros anaeróbios quando operados em série, indicou que a quase totalidade da remoção de matéria orgânica facilmente biodegradável ocorreu no primeiro filtro, evidenciando que, para o tratamento do lixiviado em questão, não é interessante a utilização de dois filtros anaeróbios de fluxo ascendente semelhantes em série. A fase 2 avaliou o desempenho dos filtros anaeróbios operados em paralelo e dos banhados construídos. Foi possível concluir-se que: filtros anaeróbios de fluxo ascendente são excelente alternativa para o tratamento de lixiviado de aterro sanitário, pois podem viabilizar remoções de matéria orgânica superiores a 50%; banhados construídos representam uma ecotecnologia interessante para o complemento do tratamento de lixiviado, pois podem viabilizar elevadas remoções de N-amoniacal. / This study discussed the sanitary landfill leachate treatment in a full scale system composed by two upflow anaerobic filters followed by two constructed wetlands. The research was developed at the landfill leachate treatment station owned by Recreio Central Waste, located in Minas do Leão/RS. The objective of the study was to verify the efficiency of the system in the removal of organic matter and ammonia nitrogen. The phase 1 of the study, which evaluated the performance of anaerobic filters when operated in series, indicated that almost all of the removal of organic matter readily biodegradable occurred in the first filter, showing that, for the treatment of leachate concerned, it is not interesting the use of two similar upflow anaerobic filters in series. The phase 2 assessed the performance of the anaerobic filters, operated in parallel, and the constructed wetlands. It could be concluded that: upflow anaerobic filters are excellent alternative for the sanitary landfill leachate treatment, as they may facilitate removal of organic matter greater than 50%; constructed wetlands represent an interesting eco-technology to complement the leachate treatment, which can enable high removals of N-ammonia.
2

Tratamento de lixiviado de aterro sanitário por um sistema composto por filtros anaeróbios seguidos de banhados construídos: estudo de caso - Central de Resíduos do Recreio, em Minas do Leão/RS / Sanitary landfill leachate treatment for a system composed by upflow anaerobic filters followed by constructed wetlands: case study - Recreio Central Waste, in Minas do Leão/RS

Ricardo Figueira Bidone 03 March 2008 (has links)
A presente pesquisa abordou o estudo em escala real do tratamento de lixiviado de aterro sanitário em um sistema composto por dois filtros anaeróbios seguidos de dois banhados construídos. O trabalho foi desenvolvido na estação de tratamento de lixiviado do aterro sanitário pertencente à Central de Resíduos do Recreio, localizada em Minas do Leão/RS. Pretendeu-se verificar a eficiência do sistema na remoção de matéria orgânica e de nitrogênio amoniacal. A fase 1 da pesquisa, que avaliou o desempenho dos filtros anaeróbios quando operados em série, indicou que a quase totalidade da remoção de matéria orgânica facilmente biodegradável ocorreu no primeiro filtro, evidenciando que, para o tratamento do lixiviado em questão, não é interessante a utilização de dois filtros anaeróbios de fluxo ascendente semelhantes em série. A fase 2 avaliou o desempenho dos filtros anaeróbios operados em paralelo e dos banhados construídos. Foi possível concluir-se que: filtros anaeróbios de fluxo ascendente são excelente alternativa para o tratamento de lixiviado de aterro sanitário, pois podem viabilizar remoções de matéria orgânica superiores a 50%; banhados construídos representam uma ecotecnologia interessante para o complemento do tratamento de lixiviado, pois podem viabilizar elevadas remoções de N-amoniacal. / This study discussed the sanitary landfill leachate treatment in a full scale system composed by two upflow anaerobic filters followed by two constructed wetlands. The research was developed at the landfill leachate treatment station owned by Recreio Central Waste, located in Minas do Leão/RS. The objective of the study was to verify the efficiency of the system in the removal of organic matter and ammonia nitrogen. The phase 1 of the study, which evaluated the performance of anaerobic filters when operated in series, indicated that almost all of the removal of organic matter readily biodegradable occurred in the first filter, showing that, for the treatment of leachate concerned, it is not interesting the use of two similar upflow anaerobic filters in series. The phase 2 assessed the performance of the anaerobic filters, operated in parallel, and the constructed wetlands. It could be concluded that: upflow anaerobic filters are excellent alternative for the sanitary landfill leachate treatment, as they may facilitate removal of organic matter greater than 50%; constructed wetlands represent an interesting eco-technology to complement the leachate treatment, which can enable high removals of N-ammonia.
3

Tratamento de lixiviado de aterros urbanos utilizando o processo foto-fenton combinado à coagulação/floculação

LEITE, Mirella de Andrade Loureiro 09 September 2016 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2017-04-25T13:44:10Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE VERSÃO FINAL _ Mirella Leite.pdf: 3354242 bytes, checksum: bb8ba120eb7e5468ab745513e0389bf0 (MD5) / Made available in DSpace on 2017-04-25T13:44:10Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE VERSÃO FINAL _ Mirella Leite.pdf: 3354242 bytes, checksum: bb8ba120eb7e5468ab745513e0389bf0 (MD5) Previous issue date: 2016-09-09 / FACEPE / A presente pesquisa foi motivada pelo desafio em propor um tratamento, em escala laboratorial, para degradar eficientemente os poluentes dos lixiviados provenientes do Aterro Sanitário de Altinho – PE, localizado no Agreste do Estado e em funcionamento e Aterro Controlado da Muribeca – PE, localizado na Região Metropolitana do Recife e fechado desde 2009. Assim, baseado na característica de alta carga orgânica, porém baixa biodegradabilidade dos lixiviados, foi realizado um tratamento físico-químico com aplicação dos processos de coagulação/floculação (CF) e oxidativos avançados do tipo foto-Fenton. Inicialmente, foi feito um tratamento preliminar dos lixiviados por meio de um planejamento fatorial 24, tendo como variáveis independentes: massa do coagulante hidróxido de cálcio, tempo e velocidade de rotação de floculação e tempo de sedimentação. Em seguida, foi aplicado o processo de fotoFenton, sob as mesmas condições, ao sobrenadante proveniente das amostras pré-tratadas por CF e diretamente às amostras brutas. Os resultados mostraram remoções de 89,6% e 83,4% de DQO para a amostra pré-tratada por CF e bruta de Altinho, respectivamente; e remoções de 91,5% e 85,2% de DQO para a amostra pré-tratada por CF e amostra bruta da Muribeca, respectivamente. Comparando esses resultados, decidiu-se pela não realização de um tratamento preliminar visto que o percentual de remoção entre as amostras pré-tratadas e brutas foram relativamente próximos, evitando assim o gasto extra de energia, materiais e tempo. Um planejamento fatorial 33 foi realizado para o tratamento por foto-Fenton para cada amostra de lixiviado dos aterros, variando-se concentração de H2O2, proporção de FeSO4.7H2O:H2O2 e pH, em um tempo reacional de 240 minutos sob radiação solar. Foram obtidos resultados de percentuais de remoções nas faixas de 52,5% a 87% de DQO, 43,5 a 77% de carbono orgânico total (COT) e 39 a 74% de substâncias húmicas (SH) para o lixiviado de Altinho; e 53 a 91% de DQO, 38,5 a 77% de COT e 30 a 64% de SH para o lixiviado da Muribeca. O estudo estatístico de correlação entre pares dessas variáveis mostrou que essas possuem correlação de moderada a altamente forte. Os dados experimentais se ajustaram a um modelo cinético de primeira ordem, alcançando-se 70% de degradação do COT dos dois lixiviados em 30 minutos de reação. Obteve-se a constante cinética (k) igual a 0,0408 min-1 e coeficiente de regressão linear (R2) igual a 0,9862 para o lixiviado de Altinho e k = 0,0373 min-1 e R2 = 0,9727 para Muribeca. A caracterização do lixiviado de Altinho e da Muribeca tratados, em suas condições ótimas, indicou um aumento da biodegradabilidade e uma remoção eficiente da carga orgânica, cor e turbidez. Os lixiviados tratados com diluição 1:10 não apresentaram toxicidade. / This research was motivated by the challenge to propose a treatment in laboratory scale to efficiently degrade pollutants of leachate from the landfill of Altinho - PE, located in the arid zone of the state and in operation, and landfill of Muribeca - PE, located in Metropolitan Region of Recife and closed since 2009. Thus, based on the high organic loading characteristic but low biodegradability of the leachates, a physical-chemical treatment with application of coagulation/flocculation (CF) and advanced oxidative (photo-Fenton) processes were made. Initially, a preliminary treatment of the leachate was done by an experimental design 24 using as independents variables: mass of the calcium hydroxide coagulant, flocculation time, flocculation rotation speed and settling time. Then, the photo-Fenton process was applied, under the same conditions, to the supernatant from the pretreated samples and directly to the raw samples. The results showed 89.6% and 83.4% COD removal for the pretreated sample by CF and raw sample from Altinho, respectively; and 91.5% and 85.2% COD removal for the pretreated sample by CF and raw sample from Muribeca, respectively. Comparing these results, it was decide not to do a pretreatment since the removal percentage between pretreated and raw samples were relatively close, avoiding the extra expense of energy, materials and time. A 33 factorial design was done for the photo-Fenton treatment to each landfills leachate sample, ranging the concentration of H2O2, the proportion of FeSO4.7H2O:H2O2 and pH, at a reaction time of 240 minutes under solar radiation. Percentages of removal results were obtained in the ranges of 52.5% to 87% of COD, 43.5 to 77% of TOC and 39 to 74% of humic substances (HS) to the Altinho’s leachate; and 53 to 91% of COD, 38.5 to 77% of TOC and 30 to 64% of HS to the Muribeca’s leachate. The statistical correlation study between pairs of these variables showed that it has a moderate to highly strong correlation. The experimental data fitted to a first order kinetic model, achieving 70% of TOC degradation for the leachate samples at 30 minutes of reaction. The rate constant (k) was 0.0408 min-1 and the linear regression coefficient (R2) was 0.9862 for Altinho´s leachate and k = 0.0373 min-1 and R2 = 0.9727 for Muribeca’s leachate. The characterization of Altinho and Muribeca treated leachate in its optimal condition, indicated an increase in biodegradability and efficient removal of organic matter, color and turbidity. The both treated leachate samples with dilution 1:10 showed no toxicity.
4

Treatment of per- and polyfluoroalkylsubstance (PFAS)-contaminated waterusing aeration foam collection

Kjellgren, Ylva January 2020 (has links)
Landfills are potential sources for PFASs and treatment techniques for landfill leachate are urgently needed. Foam fractionation is an aeration technique which utilizes the tendency of PFASs to escape the liquid phase and build foam. The foam is harvested and with it the contamination. Landfill leachate from Hovgården, Uppsala Sweden contained PFASs of higher concentration than desired and investigations into whether foam fractionation could reduce PFASs amounts were initiated. Landfill leachate containing sum PFASs of 5500 ng/L on average were aerated in two different aeration foam collection pilot set-ups for the research. The pilot set-ups were divided into two models: a batch pilot and a continuous pilot. The batch pilot was run for 60 minutes testing parameters such as column volume, air flow rate, dilution and using additives as NaCl, FeCl3 and dish soap. The continuous pilot used contact times of 5, 10 and 20 minutes with constant air flow rate and column volume and no additives. All batch experiments showed reduced concentrations of PFASs, from 62 up to 91%, with an average sum PFASs removal efficiency of 77%. Air flow rates of 4 and 6 L/min were more effective than 2 L/min to reduce the amount of PFASs. Smaller volumes got higher removal efficiency. The dilution experiments showed mixed and somewhat contradictory results, where the nondiluted experiment had removal efficiency of sum PFASs of average 77% while the 50% diluted had an average sum PFASs removal efficiency of 84%. The experiment with the greatest dilution (75%) had the lowest average sum PFASs removal efficiency as suspected, at 68%. Regarding additives, the experiments with added 0.155 and 0.313% NaCl in the leachate were most effective at removing PFASs. The dish soap and FeCl3 additives also contributed to higher PFASs reduction. The experiment with the addition of dish soap had an average sum PFASs removal efficiency of 88% compared to 77% without additives, and the highest concentration of FeCl3 (0,09% of the leachate) had an average sum PFASs removal efficiency of 85%. All continuous experiments showed reduced reduced PFASs concentrations with sum PFASs removal efficiencies ranging from 72 up to 94%, with an average of 86%. The majority of the PFASs were reduced within the first time steps for all experiments, but for the last amount to be removed the contact time needed to be longer. The column contact time of 20 min had the highest average sum PFASs removal efficiency. The conclusion is that PFASs are reduced during the treatment in the pilots and that the reduction is dependent on the chain length and functional groups of the substances, and increased with additives and increased air flow rate. The volume treated and the concentration of raw water also influenced the removal efficiency.

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