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Utilização de polímeros para condicionamento de lodo de ETE para desidratação em filtro prensa de placas.; Utilization of polymers for the conditioning of the sludge generated at Wastewater Treatment Plants (WTP) for dewatering at filter presses.

Miki, Marcelo Kenji
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 26/06/1998 PT
Relevância na Pesquisa
86.07%
Este estudo procurou investigar a utilização de polímeros para condicionamento de lodo de ETE para desidratação em filtro prensa de placa e verificar as eventuais vantagens em relação ao condicionamento com cal e cloreto férrico. Para isso foram realizadas pesquisa bibliográfica, consulta a fornecedores de polímeros e de equipamentos e trabalhos experimentais em laboratório e em escala piloto com lodo gerado nos digestores anaeróbios da ETE Barueri da SABESP que mostrava interesse em fazer o condicionamento do lodo com polímeros. Atualmente, na ETE Barueri o condicionamento de lodo é feito com cal e cloreto férrico, com dosagens em torno de 25% e 10% respectivamente e a desidratação em filtro prensa de placas, com tempo de ciclo de 4 horas, produz tortas com 40% de teor de sólidos e densidade de 1,20 kg/L. Nos experimentos foram utilizados polímeros catiônicos de alto peso molecular. O equipamento piloto utilizado foi um filtro prensa de placa do tipo membrana diafragma com dez placas de 800 x 800 mm. Nos ensaios do filtro prensa piloto, com a utilização de polímero em pó para o condicionamento de lodo, indicou-se uma redução nos custos de produtos químicos consumidos em relação ao condicionamento com cal e cloreto férrico. O condicionamento com polímero em pó e cloreto férrico...

Uso da técnica produção mais limpa em estação de tratamento de efluentes industriais.; Use of cleaner production methodology in industrial wastewater treatment plants (WTP).

Harada, Franco Hamilton
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 11/05/2006 PT
Relevância na Pesquisa
96.21%
Inserção da metodologia de Produção Mais Limpa em Estações de Tratamento de Efluentes (ETE) de indústrias no geral. O conceito fornecido pela Produção Mais Limpa permite sua aplicação aos tratamentos de fim de tubo, não se restringindo somente ao processo produtivo. A aplicação desta ferramenta visa um incremento e a melhoria contínua do sistema de gestão ambiental englobando o tratamento de todo o tipo de poluição gerada, especificamente neste trabalho, os efluentes industriais. As ETE, com um gerenciamento e operação adequados, além de minimizarem os efeitos poluidores dos efluentes gerados nas indústrias a níveis exigidos pela legislação aplicável ou a padrões de qualidade requeridos internamente em seu processo, podem controlar todo o processo produtivo interno a fábrica. Há a possibilidade de através dos diversos parâmetros processuais de controle detectar grande parte dos desvios produtivos ocorridos no interior da fábrica. Com a aplicação da ferramenta de Produção Mais Limpa em Estações de Tratamento de Efluentes Industriais, demonstra-se através de suas diversas metodologias: - A melhoria contínua em todos os processos produtivos e de tratamento de efluentes envolvidos na indústria; - O aumento progressivo das eficiências processuais; - Que investimentos e meio ambiente estão fortemente atrelados para o desenvolvimento da indústria e seu fortalecimento tanto a nível comercial quanto na sociedade. Portanto...

O lixiviado dos aterros sanitários em estações de tratamento dos sistemas públicos de esgotos; The leachate from landfill in wastewater treatment systems public sewers

Bocchiglieri, Miriam Moreira
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 11/05/2010 PT
Relevância na Pesquisa
86.26%
O presente trabalho discute o recebimento de lixiviado de aterros sanitários em estações de tratamento do sistema público de esgotos para tratamento conjunto. Descreve os processos de geração do lixiviado nos aterros e faz uma avaliação desse recebimento em quatro estações de tratamento em operação no Estado de São Paulo que empregam processos biológicos de tratamento por lodos ativados convencional e por batelada, lagoas de estabilização (anaeróbia seguida de facultativa) e lagoas aeradas. Também apresenta a variação da produção de lixiviado em aterros sanitários em função dos períodos de chuva e seca, estabelecidos pela precipitação observada no período avaliado. Conclui que o tratamento conjunto de lixiviado de aterro é uma alternativa a ser considerada no planejamento dos sistemas de resíduos sólidos e de esgotos sanitários. A adoção do tratamento conjunto traz benefícios a esses sistemas e à sociedade, pois pode representar economia de escala, atendimento às exigências legais e conformidade ambiental, promovendo melhores condições de saúde pública; This work discuss the receipt of sanitary landfill leachate by public wastewater treatment plants for joint treatment. It describes the processes theough which leachate is generated in landfills and assesses its receipt in four wastewater treatment plants in the state of São Paulo that employ biological processes such as conventional and batch activated sludge and stabilization ponds (anaerobic pond followed by facultative pond). Additionally...

Remoção de fósforo do líquido de descarte do desaguamento do lodo de estações de tratamento de esgoto mediante precipitação de estruvita; Phosphorus removal from sludge water discharge of wastewater treatment plants by struvite precipitation

Marques, José Luciano Verçosa
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 07/10/2010 PT
Relevância na Pesquisa
86.22%
A presente pesquisa estudou a viabilidade do emprego de sais de magnésio em estações de tratamento de esgoto sanitário visando a remoção do fósforo, bem como a produção de estruvita, mineral que pode ser utilizado diretamente no solo como fertilizante. As estações estudadas nesta pesquisa foram a Estação de Tratamento de Esgoto Sanitário de Franca-SP e a Estação de Tratamento de Esgoto Sanitário Jardim das Flores, localizada no município de Rio Claro-SP, e a Estação de Tratamento de Esgoto Sanitário Piçarrão, no município de Campinas. No caso da ETE Jardim das Flores (Rio Claro-SP), observou a possibilidade do emprego de sais de magnésio para se remover fósforo no efluente dos reatores UASB. Com ensaios de Jar-Test, atingiu-se cerca 49% de remoção de fosfato na amostra precipitada por gravidade e cerca de 90% na amostra centrifugada. No caso da ETE-Franca-SP, constatou-se, apesar do emprego de sais de magnésio não ter sido viável, verificou-se os benefícios do emprego de cloreto férrico em estações de tratamento de esgoto sanitário.; The present research studied the use of magnesium salts to remove phosphorus. With the phosphorus removal, magnesium salts, produce, as well, struvite, mineral that can be use directly on soil as fertilizer. The wastewater treatment plants objects of studies in this research was Wastewater Treatment Plant of Franca (SABESP) city Wastewater Treatment Plant of Jardim das Flores (Foz do Brasil)...

Ocorrência e remoção de contaminantes emergentes por tratamentos convencionais de água e esgoto; Occurrence and removal of emerging contaminants by conventional water and wastewater treatments

Igor Cardoso Pescara
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 21/11/2014 PT
Relevância na Pesquisa
76.23%
abalho teve como objetivo avaliar a eficiência dos tratamentos empregados em cinco estações de tratamento de esgoto (ETE) e duas estações de tratamento de água (ETA) na remoção dos hormônios endógenos estrona (E1), 17-estradiol (E2), estriol (E3), testosterona (TTN) e progesterona (PROG), hormônios sintéticos 17α-etinilestradiol (EE2), dietilestilbestrol (DES), norgestrel (NGT) e mestranol (MEE), produtos de uso industrial bisfenol A (BPA), fenolftaleína (PhPh), n-nonilfenol (nNP), n-octilfenol (nOP) e triclosan (TCS), o fármaco cafeína (CAF) e o pesticida atrazina (ATZ). Foi possível quantificar BPA, E1, E3, CAF e ATZ em esgoto bruto e BPA, E1, CAF e ATZ em água bruta. Para cada composto, tanto os tratamentos realizados pelas ETE quanto os realizados pelas ETA apresentaram eficiências de remoção variáveis. A cafeína foi o composto-alvo mais frequentemente encontrado nas amostras, sendo escolhida como indicador químico para avaliar a eficiência dos tratamentos. Foi encontrada uma taxa média de 99% para a remoção de CAF pelas ETE, sendo as etapas com tratamentos biológicos as mais eficientes. Os tratamentos anaeróbios apresentaram remoções médias superiores a 80% na remoção de CAF, e os tratamentos aeróbios foram capazes de remover cerca de 20% da carga do composto. Nas ETE...

Study of protozoa population in wastewater treatment plants by image analysis

Motta, Maurício da; Pons, M. N.; Vivier, H.; Amaral, A. L.; Ferreira, E. C.; Roche, N.; Mota, M.
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Conferência ou Objeto de Conferência
Publicado em //2000 ENG
Relevância na Pesquisa
86.07%
Protozoa are important micro-organisms taking part to the ecosystem balance in wastewater treatment plants. A procedure for their semi-automated identification and counting based on image analysis is proposed. The main difficulty is the segmentation of the protozoa as most of them are in contact with the sludge. The protozoa are characterized by the size of their silhouette (area and length) and three shape factors (elongation, circularity and eccentricity). The identification is performed after projecting the resulting 5D space into a 3D space of Principal Components. The rate of automated identification is actually higher than 50% for some of the species found commonly in activated sludge.

Study of Protozoa population in wastewater treatment plants by image analysis

Motta, Maurício da; Pons, M. N.; Vivier, H.; Amaral, A. L.; Ferreira, E. C.; Roche, N.; Mota, M.
Fonte: Brazilian Society of Chemical engineering Publicador: Brazilian Society of Chemical engineering
Tipo: Artigo de Revista Científica
Publicado em /03/2001 ENG
Relevância na Pesquisa
86.07%
Protozoa are important microorganisms taking part to the ecosystem balance in wastewater treatment plants. A procedure for their semi-automated identification and counting based on image analysis is proposed. The main difficulty is the segmentation of the protozoa as most of them are in contact with the sludge. The protozoa are characterized by the size of their silhouette (area and length) and three shape factors (elongation, circularity and eccentricity). They are identified after projecting the resulting 5D space into a 3D space of principal components. The rate of automated identification is actually higher than 50% for some of the species commonly found in activated sludge.; National Council of Scientific and Technological Development of Brazil (CNPq). Embassy of France in Portugal. Instituto de Cooperação Científica e Tecnológica Internacional (ICCTI).

Ciprofloxacin resistance in domestic wastewater treatment plants

Manaia, Célia M.; Novo, Ana; Coelho, Bruno; Nunes, Olga C.
Fonte: Springer Verlag Publicador: Springer Verlag
Tipo: Artigo de Revista Científica
Publicado em //2010 ENG
Relevância na Pesquisa
76.24%
The potential of domestic wastewater treatment plants to contribute for the dissemination of ciprofloxacin-resistant bacteria was assessed. Differences on bacterial counts and percentage of resistance in the raw wastewater could not be explained on basis of the size of the plant or demographic characteristics of population served. In contrast, the treated effluent of the larger plants had significantly more heterotrophs and enterobacteria, including ciprofloxacin-resistant organisms, than the smaller (p<0.01). Moreover, longer hydraulic retention times were associated with significantly higher percentages of resistant enterobacteria in the treated effluent (p<0.05). Independently of the size or type of treatment used, domestic wastewater treatment plants discharged per day at least 1010–1014 colony forming units of ciprofloxacin-resistant bacteria into the receiving environment.

Factors influencing antibiotic resistance burden in municipal wastewater treatment plants

Novo, Ana; Manaia, Célia M.
Fonte: Springer Publicador: Springer
Tipo: Artigo de Revista Científica
Publicado em //2010 ENG
Relevância na Pesquisa
86.25%
Municipal wastewater treatment plants are recognized reservoirs of antibiotic-resistant bacteria. Three municipal wastewater treatment plants differing on the dimensions and bio-treatment processes were compared for the loads of amoxicillin-, tetracycline-, and ciprofloxacinresistant heterotrophic bacteria, enterobacteria, and enterococci in the raw inflow and in the treated effluents. The sewage received by each plant, in average, corresponded to 85,000 inhabitant equivalents (IE), including pretreated industrial effluents (≤30%) in plant activated sludge, 105,000 IE, including pretreated hospital effluents (≤15%) in plant trickling filter, and 2,000 IE, exclusively of domestic sewage, in plant submerged aerated filter. The presence of pretreated industrial effluents or of pretreated hospital sewage in the raw inflow did not imply significantly higher densities (per milliliter or per IE) of antibiotic-resistant bacteria in the raw wastewater. Longer hydraulic residence periods (24 h) corresponded to higher bacterial removal rates than shorter periods (12 and 9 h), although such efficiency did not imply significant average decreases in the antibiotic resistance prevalence of the treated effluent. The bacterial loads in the treated effluent could be ranked according to the treatment efficiency...

A simulation benchmark to evaluate the performance of advanced control techniques in biological wastewater treatment plants

Sotomayor,O.A.Z.; Park,S.W.; Garcia,C.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2001 EN
Relevância na Pesquisa
96.2%
Wastewater treatment plants (WWTP) are complex systems that incorporate a large number of biological, physicochemical and biochemical processes. They are large and nonlinear systems subject to great disturbances in incoming loads. The primary goal of a WWTP is to reduce pollutants and the second goal is disturbance rejection, in order to obtain good effluent quality. Modeling and computer simulations are key tools in the achievement of these two goals. They are essential to describe, predict and control the complicated interactions of the processes. Numerous control techniques (algorithms) and control strategies (structures) have been suggested to regulate WWTP; however, it is difficult to make a discerning performance evaluation due to the nonuniformity of the simulated plants used. The main objective of this paper is to present a benchmark of an entire biological wastewater treatment plant in order to evaluate, through simulations, different control techniques. This benchmark plays the role of an activated sludge process used for removal of organic matter and nitrogen from domestic effluents. The development of this simulator is based on models widely accepted by the international community and is implemented in Matlab/Simulink (The MathWorks...

The study of protozoa population in wastewater treatment plants by image analysis

Motta,M.da; Pons,M.N.; Vivier,H.; Amaral,A.L.; Ferreira,E.C.; Roche,N.; Mota,M.
Fonte: Brazilian Society of Chemical Engineering Publicador: Brazilian Society of Chemical Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2001 EN
Relevância na Pesquisa
86.07%
Protozoa are important microorganisms for the ecosystem balance in wastewater treatment plants. A procedure for their semi-automated identification and counting based on image analysis is proposed. The main difficulty is segmentation of the protozoa as most of them are in contact with the sludge. The protozoa are characterized by the size of their silhouette (area and length) and three shape factors (elongation, circularity and eccentricity). They are identified after projecting the resulting 5D space into a 3D space of principal components. The rate of automated identification is actually higher than 50% for some of the species commonly found in activated sludge.

Transformation of PVP coated silver nanoparticles in a simulated wastewater treatment process and the effect on microbial communities

Doolette, C.; McLaughlin, M.; Kirby, J.; Batstone, D.; Harris, H.; Ge, H.; Cornelis, G.
Fonte: BioMed Central Ltd Publicador: BioMed Central Ltd
Tipo: Artigo de Revista Científica
Publicado em //2013 EN
Relevância na Pesquisa
76.24%
Background: Manufactured silver nanoparticles (AgNPs) are one of the most commonly used nanomaterials in consumer goods and consequently their concentrations in wastewater and hence wastewater treatment plants are predicted to increase. We investigated the fate of AgNPs in sludge that was subjected to aerobic and anaerobic treatment and the impact of AgNPs on microbial processes and communities. The initial identification of AgNPs in sludge was carried out using transmission electron microscopy (TEM) with energy dispersive X-ray (EDX) analysis. The solid phase speciation of silver in sludge and wastewater influent was then examined using X-ray absorption spectroscopy (XAS). The effects of transformed AgNPs (mainly Ag-S phases) on nitrification, wastewater microbial populations and, for the first time, methanogenesis was investigated. Results: Sequencing batch reactor experiments and anaerobic batch tests, both demonstrated that nitrification rate and methane production were not affected by the addition of AgNPs [at 2.5 mg Ag L-1 (4.9 g L-1 total suspended solids, TSS) and 183.6 mg Ag kg -1 (2.9 g kg-1 total solids, TS), respectively]. The low toxicity is most likely due to AgNP sulfidation. XAS analysis showed that sulfur bonded Ag was the dominant Ag species in both aerobic (activated sludge) and anaerobic sludge. In AgNP and AgNO3 spiked aerobic sludge...

Review of Community-Managed Decentralized Wastewater Treatment Systems in Indonesia

Eales, Kathy; Blackett, Isabel; Siregar, Reini; Febriani, Evi
Fonte: World Bank, Washington, Dc Publicador: World Bank, Washington, Dc
Tipo: Publications & Research :: Working Paper
ENGLISH; EN_US
Relevância na Pesquisa
76.21%
Effective management of sanitation and wastewater is a growing challenge in dense urban settlements. Rapidly increasing urbanization and, along with that, rising settlement densities in low-income urban and peri-urban areas highlight the need for sanitation technologies and management systems that are robust and affordable, and which lessen the pollution load on local water sources. In many developing countries, centralized sewerage and wastewater treatment systems cover only a portion of larger urban areas, and are often not yet planned for smaller towns and densely populated, low-income areas of cities. On-site sanitation is often inappropriate in the denser settlements and slum areas, thus requiring intermediate and complementary solutions. Decentralized wastewater treatment systems (DEWATS) connected to simplified sewer systems or communal sanitation centers have the potential to close the gap between on-site and centralized systems. Community-managed DEWATS offer the possibility of swift sanitation improvements in high priority neighborhoods that communities can manage themselves...

Minimização da produção de lodo no tratamento de águas de abastecimento mediante uso do cloreto de polialumínio e sua disposição em estações de tratamento de esgotos; Minimization of water treatment plant sludge production with polyaluminium chloride application and its disposal in wastewater treatment plants

FERREIRA FILHO, Sidney Seckler; WAELKENS, Bárbara Elisabeth
Fonte: ABES Publicador: ABES
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
86.1%
Uma das possibilidades para a redução da produção de lodo em estações de tratamento de água (ETAs) é o uso do cloreto de polialumínio (CPA) como coagulante, que pode ser aplicado de forma isolada ou em conjunto com sais de ferro. Este trabalho objetivou estudar o uso do CPA no que diz respeito à produção de lodo, bem como avaliar o impacto do lançamento de lodos de ETAs em estações de tratamento de esgoto (ETEs) do tipo lodos ativados convencional. Observou-se que a produção de lodo do CPA apresentou valores próximos em comparação ao sulfato de alumínio, em torno de 4,75 mg de massa seca para cada 1 mg de Al, e o seu eventual lançamento para posterior processamento em ETEs deverá alterar a qualidade físico-química do lodo desidratado, sendo esta função do tipo e dosagem de coagulante e suas impurezas.; One possible strategy to reduce sludge production in water treatment plant (WTP) is the application of polyaluminium chloride (PAC) as the sole coagulant or together with iron salts. The purpose of this paper was to investigate PAC usage with regard to sludge production as well as to evaluate impacts of discharging WTP sludge in activated sludge wastewater treatment plants (WWTPs). It was observed that PAC-based sludge production presented values close to aluminum sulfate-based sludge production...

Simultaneous extraction and fate of linear alkylbenzene sulfonates, coconut diethanol amides, nonylphenol ethoxylates and their degradation products in wastewater treatment plants, receiving coastal waters and sediments in the Catalonian area (NE Spain)

González Blanco, Susana; Petrovic, Mira; Barceló, Damià
Fonte: Elsevier Publicador: Elsevier
Tipo: Artículo Formato: 22195 bytes; application/pdf
ENG
Relevância na Pesquisa
96.14%
10 pages, 4 figures, 5 tables.-- PMID: 15527127 [PubMed].-- Printed version published Oct 15, 2004.-- Presented at the 3rd Meeting of the Spanish Association of Chromatography and Related Techniques and the European Workshop: 3rd Waste Water Cluster, Aguadulce (Almeria), Spain, Nov 19–21, 2003.; The efficiency of six wastewater treatment plants (WWTPs) in the Catalonian region to remove several classes of ionic and non-ionic surfactants was investigated, using solid-phase extraction (SPE) followed by liquid chromatography–mass spectrometry (LC–MS). Occurrence and distribution of linear alkylbenzene sulfonates (LASs), coconut diethanol amides (CDEAs), nonylphenol ethoxylates (NPEOs) and their degradation products were studied in coastal areas receiving WWTP effluents. For the analysis of sediment samples pressurized liquid extraction (PLE) followed by SPE extract clean-up and LC–MS detection was used for simultaneous extraction of all target compounds. Concentrations of parent long ethoxy chain NPEOs in raw water entering WWTPs ranged from 60 to 190 μg/L. In effluents concentrations ranged from 2.8 to 6.6 μg/L, which corresponded to an average primary elimination of 93–96%. Nonylphenol (NP) was found in concentrations from 0.2 to 18 μg/L in WWTP influents and up to 5 μg/L in the treated water...

Application of control strategies in wastewater treatment plants for effluent quality improvement, costs reduction and effluent limits violations removal

Santín López, Ignacio
Fonte: [Barcelona] : Universitat Autònoma de Barcelona, Publicador: [Barcelona] : Universitat Autònoma de Barcelona,
Tipo: Tesis i dissertacions electròniques; info:eu-repo/semantics/doctoralThesis; info:eu-repo/semantics/publishedVersion Formato: application/pdf
Publicado em //2015 ENG
Relevância na Pesquisa
96.18%
En este trabajo se aplican diferentes estrategias de control en las plantas de tratamiento de aguas residuales. El primer objetivo es la mejora del rendimiento de control. Básicamente, esto sirve como una prueba de que la estrategia de control propuesta se ha aplicado correctamente. El objetivo final es el efecto de la estrategia de control aplicada sobre el rendimiento de la planta. En concreto, mejorar la calidad del efluente, reducir costes de operación y evitar violaciones de los límites establecidos en el efluente. La evaluación de las diferentes estrategias de control se lleva a cabo en primer lugar con el Benchmark Simulation Model No. 1 (BSM1), y en segundo lugar con Benchmark Simulation Model No. 2 (BSM2). BSM1 se centra en el tratamiento biológico mediante reactores de lodos activos, y la evaluación se basa en una semana de simulación. BSM2 es una versión extendida del BSM1, agregando el tratamiento de lodos y proporciona un afluente más elaborado y variable, con un año de evaluación. Los enfoques de control se basan en Control Predictivo basado en Modelo, control difuso, funciones que relacionan las variables de entrada y las manipuladas, y Redes Neuronales Artificiales. El Control Predictivo basado en Modelo se propone para una mejora del tracking. El control difuso y las funciones se implementan para mejorar los procesos de desnitrificación o de nitrificación en base a los objetivos propuestos. Sus parámetros de sintonía se seleccionan mediante análisis trade-off. Las Redes Neuronales Artificiales se aplican para detectar riesgo de violaciones y obtener una selección automática de la estrategia de control adecuada. Se muestran los resultados y se comparan con las estrategias de control por defecto y con la literatura. Para el rendimiento de control...

Microbial Impacts of Selected Pharmaceutically Active Compounds Found in Domestic Wastewater Treatment Plants

Wang, Shuyi
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Dissertação Formato: 2262475 bytes; application/pdf
Publicado em //2009 EN_US
Relevância na Pesquisa
86.2%

Large amounts of human pharmaceutical products are consumed worldwide. Many drugs and their metabolites, referred to as pharmaceutically active compounds (PhACs), are not fully metabolized prior to household discharge resulting in their common occurrence in wastewater treatment plants (WWTPs). In most instances, WWTPs present the first treatment opportunity for removing PhACs and preventing significant environmental exposure. Because most municipal WWTPs rely on the microbial component of the activated sludge process, there is a need to estimate the influence of PhACs in wastewater influent on the activated sludge microbial communities and the treatment performance of WWTPs. The objective of this dissertation was to determine the impact of selected PhACs (i.e., ketoprofen, naproxen, clofibric acid, carbamazepine and gemfibrozil) on activated sludge microorganisms and key individual microbial species in domestic wastewater treatment. Analyses were performed in batch reactors initially and then in laboratory-scale sequencing batch reactors (SBR) which mimic WWTP operations. Ammonia oxidizing bacteria (AOB) were selected as indicator organisms because of their importance in wastewater treatment and demonstrated sensitiveness to toxic compounds.

The batch experiments results suggested that microbial growth inhibition was correlated to organic loadings. In the presence of 0.2% (v/v) ethanol...

Analysis of the investment costs in municipal wastewater treatment plants in Cundinamarca

Rodríguez-Miranda,Juan Pablo; García-Ubaque,César Augusto; Penagos-Londoño,Juan Carlos
Fonte: DYNA Publicador: DYNA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2015 EN
Relevância na Pesquisa
86.23%
Some of the most significant aspects in the selection of wastewater treatment plants are the investment costs, since they cross-linkthe treatment level, the quality of the raw wastewater, the design flow and the purpose of the treated wastewater. Through a multivariable exponential regression analysis, data from 51 projects of new treatment plants was analyzed, and from that process, data of cost scale elasticity was obtained, in slow growth, in comparison to the design flow for each of the treatment technologies analyzed.

Abundance of pathogenic bacteria and viral indicators in chlorinated effluents produced by four wastewater treatment plants in the Gauteng Province, South Africa

Dungeni,M; van der Merwe,RR; Momba,MNB
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/2010 EN
Relevância na Pesquisa
76.23%
The failure of South African wastewater treatment plants to produce effluents of a high microbiological quality is a matter of great concern in terms of the pollution of water resources. This study aimed at assessing the effectiveness of 4 wastewater treatment plants in the Gauteng Province, namely the Zeekoegat, Baviaanspoort, Rayton and Refilwe Water Care Works (WCW), in the removal of pathogenic bacteria and viral indicators. Also taken into consideration were free chlorine concentrations and turbidity levels, which were measured using standard methods. Conventional methods and/or polymerase chain reaction (PCR) techniques were used to detect and identify pathogenic bacteria and coliphages. The turbidity ranged from 2.39 to 62.40 NTU and the concentrations of free chlorine ranged from 0.03 to1.60 mg-t"¹ for all plants. Despite high free chlorine residual concentrations in treated effluents, the survival and occurrence of Escherichia coli, Salmonella typhimurium and Vibrio cholerae were significantly higher at Baviaanspoort (100%, 88.2% and 35.3%), Refilwe (87.5%, 59.4% and 21.9%) and Rayton (75%, 38.2% and 9.4%) compared to Zeekoegat, which only showed the survival of E. coli, at a much lower occurrence rate of 8.8%. Somatic and F-RNA coliphages were removed at 15.57 % and 13.96% for Baviaanspoort...

The occurrence of pathogenic Escherichia coli in South African wastewater treatment plants as detected by multiplex PCR

Omar,KB; Barnard,TG
Fonte: Water SA Publicador: Water SA
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2010 EN
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The aim of this study was to investigate the use of PCR to detect commensal and diarrhoeagenic Escherichia coli concentrated from water samples using membrane filtration. To achieve this, culture-based and PCR-based methods were compared for the detection of E. coli in raw sewage and primary, secondary and tertiary effluents from 6 wastewater treatment plants around Johannesburg, Gauteng. E. coli was concentrated from the samples using standard filtration techniques with subsequent incubation on E. coli/coliform chromogenic media to determine the E. coli levels. Bacterial DNA was isolated from bacterial colonies trapped on polyethersulphone membranes after filtration using a celite/guanidium thiocyanate method. A single multiplex PCR (m-PCR) assay was used that targeted the mdh, eaeA, stx1, stx2, st, lt, ial and eagg genes associated with diarrhoeagenic E. coli. The mdh gene was detected in all of the samples even if no culturable E. coli was detected. All the diarrhoeagenic E. coli types were detected in one or more of the raw sewage samples from the various plants. EPEC was present in 20% (2/10) of the samples, EHEC in 50% (5/10), ETEC in 80% (8/10), EIEC in 10% (1/10) and EAEC in 90% (9/10) of the samples. In the case of the primary and secondary treatment only ETEC (5/5; 100%) and EAEC (5/5; 100%) were detected in all of the samples. The results demonstrate that molecular techniques such as PCR have the potential to be used for the monitoring of water samples for the presence of pathogenic E. coli...