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DeterminaÃÃo de Micropoluentes Emergentes em Esgoto SanitÃrio, Hospitalar e Ãguas Superficiais / Determination of Emerging Micropollutants in Sewage, and Surface Water HospitalNeyliane Costa de Souza 18 November 2011 (has links)
FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / No Brasil, estudos de avaliaÃÃo de micropoluentes emergentes em matrizes ambientais como esgotos sanitÃrios e hospitalares, e corpos de Ãgua, ainda sÃo bastante incipientes, assim como a remoÃÃo desses compostos em EstaÃÃes de Tratamento de Esgotos (ETEs) de baixo custo como lagoas de estabilizaÃÃo, assim como em sistemas de lodos ativados e sistemas anaerÃbio-aerÃbio compactos. O presente trabalho teve como objetivo geral investigar a presenÃa de micropoluentes em matrizes ambientais como esgotos sanitÃrios e hospitalares, e Ãgua superficial, avaliar a remoÃÃo destes compostos em ETEs de baixo custo e aplicar o processo de oxidaÃÃo avanÃada (POA) UV/H2O2 como opÃÃo de pÃs-tratamento. Os principais micropoluentes emergentes estudados foram: 2,4,6-triclorofenol, pentaclorofenol, cafeÃna (CAF), dipirona (DIP), diclofenaco de sÃdio (DCF), bis (2-etil-hexil) ftalato (DEHP), estrona (E1), 17β-estradiol (E2), β-estradiol 17-acetato (EA2), 17α-etinilestradiol (EE2) e colesterol (COL). As amostras foram coletadas em ETEs localizadas em Fortaleza e em sua regiÃo metropolitana. Os corpos receptores investigados foram o Rio Maranguapinho e o Riacho Paupina. Para a prÃ-concentraÃÃo dos micropoluentes utilizou-se extraÃÃo em fase sÃlida (SPE) com cartuchos C-18 e extraÃÃo lÃquido-lÃquido (ELL). A SPE foi a tÃcnica mais eficiente na concentraÃÃo da maioria dos micropoluentes emergentes, e a ELL se mostrou a melhor tÃcnica para compostos organoclorados. Foram realizados estudos de otimizaÃÃo das condiÃÃes de detecÃÃo dos compostos pelo uso de tÃcnicas de cromatografia gasosa acoplada à espectrometria de massas (GC/MS). Foram identificados compostos farmacÃuticos e desreguladores endÃcrinos em todas as amostras de esgotos com as seguintes faixas de concentraÃÃes efluentes: CAF (3,0-15,8 μg/L), DIP (0,3 μg/L), DCF (1,9 μg/L), DEHP (0,01-8,5μg/L), E1 (0,04-1,7 μg/L), E2 (0,03-4,0 μg/L), EA2 (0,14-9,3 μg/L), EE2 (1,0 μg/L) e COL (0,01-6,2 μg/L). Nos dois corpos receptores estudados (Rio Maranguapinho e Riacho Paupina) foram identificados desreguladores endÃcrinos. Os tratamentos realizados pelas ETEs nÃo foram suficientes para remoÃÃo total de todos os micropoluentes estudados, no entanto, a eficiÃncia para a maioria dos compostos foi acima de 50%. Em se tratando da avaliaÃÃo em sistemas de lagoas de estabilizaÃÃo, o estudo revelou boas eficiÃncias de remoÃÃo em sistemas constituÃdos de lagoa anaerÃbia seguida de facultativa e de maturaÃÃo, sendo os menores valores de remoÃÃo alcanÃados quando uma Ãnica lagoa facultativa primÃria estava presente. A avaliaÃÃo do uso do POA por meio do planejamento fatorial multivariado revelou que as melhores condiÃÃes para remoÃÃo de micropoluentes emergentes foram pH Ãcido (pH 3), concentraÃÃo de perÃxido de hidrogÃnio acima de 400 mg/L e tempos de detenÃÃo hidrÃulica no reator acima de 50min. / In Brazil, studies evaluating emerging micropollutants in environmental matrices such as sewage and hospital wastewater, as well as surface waters, are still quite incipient as well as the removal of these compounds in low cost Wastewater Treatment Plants (WWTPs) such as stabilization ponds, as well as in activated sludge systems or anaerobic/aerobic compact systems. This work aimed to investigate the presence of micropollutants in environmental matrices such as sewage and hospital wastewaters, and in surface waters. Additionally, this study evaluated the removal of these compounds in low-cost WWTPs and studied the advanced oxidation process (AOP) â UV/H2O2 â as a post-treatment option. The main emerging micropollutants studied were: 2,4,6-trichlorophenol, pentachlorophenol, caffeine (CAF), dipyrone (DIP), sodium diclofenac (DCF), bis (2-ethylhexyl) phthalate (DEHP), estrone (E1), 17β-estradiol (E2), estradiol acetate (EA2), 17α-ethinyl estradiol (EE2) and cholesterol (CHO). The samples were collected from WWTPs located in Fortaleza and its metropolitan region. The receiving surface waters investigated were: Maranguapinho River and Paupina Creek. For the pre-concentration studies of micropollutants, solid phase extraction (SPE) with C-18 cartridges was used, as well as the liquid-liquid extraction (LLE) method. The SPE technique was the most efficient method in concentrating the majority of emerging micropollutants, and the LLE proved to be the best technique for organochlorine compounds. Optimization studies were performed to detect the ideal conditions to determine the compounds by using gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS) techniques. In all wastewater samples pharmaceuticals and endocrine disrupting compounds were identified, and the range of effluent concentrations were: CAF (3.0-15.8 μg/L), DIP (0.3 μg/L), DCF (1.9 μg/L), DEHP (0.01-8.5μg/L), E1 (0.04-1.7 μg/L), E2 (0.03-4.0 μg/L), EA2 (0.14-9.3 μg/L), EE2 (1.0 μg/L) and CHO (0.01-6.2 μg/L). Endocrine disrupting compounds were identified in the Maranguapinho River and Paupina Creek. The wastewater treatment in the WWTPs was not enough for the complete removal of all micropollutants studied; however, the efficiency level for most of compounds was above 50%. Regarding the evaluation in stabilization ponds systems, the study revealed good removal of micropollutants in systems composed of anaerobic pond followed by facultative and maturation ponds, in which the lowest efficiency levels were verified when a single facultative pond was present. The evaluation of the AOP as a post-treatment option by multivariate factorial design showed that the optimal conditions for the removal of emerging micropollutants were acidic pH (pH 3), hydrogen peroxide concentration above 400 mg/L and hydraulic retention times in the reactor above 50 minutes.
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