Dissertations / Theses: 'Wastewater treatment. eng'

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Santos, Samantha Christine. "Sistema de tratamento anaeróbio, aeróbio e anóxico para águas residuárias de suinocultura : remoção de matéria orgânica, de nutrientes e de coliformes /." Jaboticabal : [s.n.], 2011. http://hdl.handle.net/11449/94941.

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Orientador: Roberto Alves de Oliveira
Banca: Carlos Augusto de Lemos Chernicharo
Banca: Edson Aparecido Abdul Nour
Resumo: Neste estudo avaliou-se o desempenho de processo anaeróbio, aeróbio e anóxico, utilizando-se um reator anaeróbio compartimentado (ABR de 360 L), com duas câmaras, um filtro aerado submerso (FAS de 160 L), preenchido com anéis de bambu e anéis de plástico de eletroduto corrugado e um reator de fluxo ascendente com manta de lodo (USB de 120 L) anóxico, instalados em série, para o tratamento de águas residuárias de suinocultura, com concentrações médias de sólidos suspensos totais (SST) de 10708 a 17048 mg L-1. Os tempos de detenção hidráulica (TDH) foram de 24 e 12 h no reator ABR; de 7,9 e 3,9 h e de 9,1 e 4,5 h no FAS preenchido com anéis de bambu e anéis de plástico de eletroduto corrugado, respectivamente; e de 7,8 e 3,9 h no reator USB anóxico. O FAS foi submetido a condições de aeração intermitente e contínua. As eficiências médias de remoção de DQOtotal foram de 94 a 99% no sistema de tratamento anaeróbio, aeróbio e anóxico, com carga orgânica volumétrica (COV) de 35,9 a 93,0 g DQOtotal (L d)-1 no reator ABR. As maiores eficiências médias de remoção foram de 99,99; 98; 99; 91; 88; 99 e 94% para os coliformes termotolerantes, DQOdiss, SST, NT, P-total, Cu e Zn, respectivamente, no sistema de tratamento anaeróbio, aeróbio e anóxico, obtendo-se valores mínimos de 1,1 x 103 NMP/100 mL para coliformes termotolerantes e 221 mg L-1 para DQOtotal. A porcentagem de CH4 no biogás do ABR variou de 76 a 84%; de N2 no reator USB anóxico chegou a 74%, com COV de 13,1 g DQOtotal (L d)-1 e TDH de 4 h. Os valores da atividade específica da microbiota do lodo das câmaras do ABR apresentaram diferenças, evidenciado a habilidade de separação das fases hidrolítica, acidogênica e metanogênica. A caracterização morfológica do biofilme do FAS, por meio de microscopia óptica, indicou alta diversidade morfológica, a qual pode estar associada a sistemas de tratamento biológico estáveis
Abstract: In this study it was evaluated the performance of the anaerobic, aerobic and anoxic process in an anaerobic baffled reactor (ABR of 360 L), with two chambers, a submerged aerated filter (SAF of 160 L), filled with bamboo rings and plastic rings, and an anoxic upflow sludge blanket reactor (USB of 120 L), installed in series, for swine wastewater treatment, with mean total suspended solid (TSS) concentration from 10708 to 17048 mg L-1. The hydraulic detention times (HDT) were 24 and 12 h in the ABR reactor; 7,9 e 3,9 h and 9,1 e 4,5 h in the SAF filled with bamboo rings and plastic rings, respectively; 7,8 and 3,9 h in the anoxic USB reactor. Conditions of intermittent and continuous aeration were applied at the SAF. The mean of CODtotal removal efficiencies ranged from 94 to 99% in the anaerobic, aerobic and anoxic treatment system under organic loading rate (OLR) of 35,9 to 93,0 g total COD (L d)-1 in the ABR reactor. The highest mean removal efficiencies were of 99,99; 98; 99; 91; 88; 99 e 94% for thermotolerant coliforms, dissCOD, TSS, TN, total-P, Cu and Zn, respectively, in the anaerobic, aerobic and anoxic treatment system, obtaining minimum values of 1,1 x 103 MPN/100 mL for thermotolerant coliforms and 221 mg L-1 for CODtotal. The CH4 percentage in the biogas ABR ranged from 76 to 84%; the N2 percentage in the anoxic USB reactor reached 74%, with COV of 13,1 g total COD (L d) -1 and HDT of 4 h. The observed values of microbial specific activity of the sludge in the ABR‟s chambers were significantly different, evidenced the ability to phase separation hydrolytic, acidogenic and methanogenic. The SAF biofilm morphology, through optical microscopy, indicated a high morphological diversity, which may be associated with stable biological treatment systems
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Lopes, Marcelo Domingos Chamma 1971. "Aplicação de água residuária de suinocultura tratada em sistema de alagados construídos, via irrigação por gotejamento nas culturas de milho e de sorgo /." Botucatu : [s.n.], 2007. http://hdl.handle.net/11449/103449.

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Resumo: Este trabalho teve como finalidade avaliar o tratamento da água proveniente de suinocultura na fase de reprodução por meio de um sistema de alagados construídos. Aplicou-se a água residuária via irrigação localizada por gotejamento nas culturas do milho safrinha e do sorgo. Realizou-se a caracterização química da água servida e da água residuária em quatro pontos de coletas em três épocas distintos, analisou-se também turbidez; coliformes totais e fecais; sólidos totais, dissolvidos e em suspensão; DBO; DQO; e condutividade elétrica da água. Realizou-se a caracterização química do solo e da solução do solo (extrator de solução) em quatro camadas (0-20; 20-40; 40-60; 60- 80cm) em três épocas distintas para irrigação com água residuária e para irrigação com água potável. Os experimentos foram efetuados na Fazenda Experimental Lageado, conjuntamente nos Campus da Faculdade de Ciências Agronômicas e da Faculdade de Medicina Veterinária e Zootecnia - UNESP Botucatu. Concluiu-se que o sistema de alagados construídos proporcionou redução nos teores de Coliformes totais e fecais, DBO, DQO, N, K, Cu, Zn e que a água tratada no sistema de alagados construídos pode ser utilizada via irrigação sem causar prejuízos à produtividade da cultura do milho safrinha.
Abstract: This work had as purpose to evaluate swine wastewater treatment through wetland systems. Treated wastewater was applied through drip irrigation system on sorghum and corn crops. Wastewater was analyzed at four sampling points and three different times; it was analyzed turbidity, total coliform bacteria and fecal coliform bacteria, total soluble solid content, dissolved solids, suspended solids, BOD, COD, and electrical conductivity. It was carried out the chemical characterization of soil and soil solution (porous ceramic cup extractors) in four layers (0-20; 20-40; 40-60; 60-80 cm) at three distinct times for wastewater irrigation and drinkable water irrigation. Experiments were carried out at Experimental Farm Lageado, jointly in the Campuses of the College of Agronômicas Sciences and the College of Medicine Veterinária and Zootecnia - UNESP Botucatu. It was concluded that the Wetland systems decreased total coliform bacteria and fecal coliform bacteria, BOD, COD, N, K, Cu, Zn. Wastewater treated on wetland systems can be used through irrigation without causing damage to corn yield.
Orientador: Eduardo Luiz de Oliveira
Coorientador: Ana Beatriz Rocha de Castro Lopes
Banca: Antônio de Pádua Sousa
Banca: Leandro José Grava de Godoy
Banca: Luiza Helena Duenhas
Banca: Elza Alves
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Giafferis, Giselda Passos 1965. "Avaliação do potencial de reuso agrícola do efluente de uma estação de tratamento de esgoto com alagados construídos /." Botucatu : [s.n.], 2011. http://hdl.handle.net/11449/101958.

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Orientador: Zacarias Xavier de Barros
Coorientador: Eduardo Luiz de Oliveira
Banca: Jorge Hamada
Banca: Jandira Liria B. Talamoni
Banca: Marco Antinio M.Biaggioni
Banca: Luis Fernando Rossi Léo
Resumo : Os sistemas de alagados construídos (SACs) são projetados como passivos de depuração, constituídos por lagoas ou canais, compostos por plantas aquáticas livres ou fixas em substratos como areia, solo ou cascalho, onde ocorre a proliferação de biofilmes que agregam populações variadas de micro-organismos presentes nas águas residuárias. O uso combinado de tecnologias simples e de baixo custo como os reatores anaeróbios seguidos de alagados construídos como pós-tratamento, tem sido de interesse para o saneamento em pequenas comunidades. A pesquisa ocorreu em uma planta de tratamento de esgoto real do Departamento de Água e Esgoto de Bauru, localizada no Distrito de Tibiriçá, com vazão média de 4,8L/s, composta por processo de filtro anaeróbio de fluxo ascendente, seguido de sistemas de alagados construídos em paralelo. Como objetivo deste trabalho, buscou-se avaliar a eficiência dos três sistemas de alagados construídos, com tipos de plantas diferentes e analisar quantitativa e qualitativamente os efluentes nas várias etapas do processo de tratamento, para verificar suas eficiências e a possibilidade de reúso do efluente final na agricultura. Diante dos resultados obtidos, observou-se que houve satisfatória remoção de matéria orgânica, com concentração média de 36 e 39 mg/L, nas fases 1 e 2 de operação,respectivamente, atendendo os valores exigidos pela legislação para padrões de emissão, mesmo recebendo concentrações afluentes elevadas, de efluentes não doméstico por batelada, o qual não foi previsto em projeto. Constatou-se que as concentrações de nutrientes, como nitrogênio e fosfato foram altas em todo o sistema e a eficiência de remoção de nitrogênio amoniacal esteve muito abaixo do esperado, não atendendo a legislação que exige lançamentos... (Resumo completo, clicar aesso eletrônico abaixo)
Abstract: The constructed wetland systems are designed as passive purification, consisting of ponds or channels, composed of aquatic plants free or fixed on substrates such as sand, soil or gravel, where the proliferation of biofilms is that aggregate diverse populations of micro- organisms present in wastewater. The combined use of simple and inexpensive as the anaerobic reactors followed by constructed wetlands as post-treatment has been of interest for sanitation in small communities. The research took place in a sewage treatment plant's actual Department of Water & Sewer Bauru, located in the District of Tibiriçá with average flow of 4.8 L/s made by a process of upflow anaerobic filter, followed by systems constructed wetlands in parallel. As objective of this study we sought to evaluate the effectiveness of three constructed wetland systems, with different types of plants and analyze quantitative and qualitative effluent at various stages of treatment to monitor their effectiveness and the possibility of reuse in the final effluent agriculture. Considering the results obtained, it was observed that there was satisfactory removal of organic matter, with a mean concentration of 36 and 39 mg/L, phases 1 and 2 operations, respectively, given the values required by law for emission standards, even with affluent high concentrations of non-domestic waste per batch, which was not foreseen in the project. It was found that concentrations of nutrients such as nitrogen and phosphate were high throughout the system and the removal efficiency of ammonia nitrogen was much lower than expected, does not meet the law requires that releases up to 20 mg/L. The results obtained for nitrogen and phosphate in effluent from constructed wetland systems, it is concluded that the system is also functioning as a secondary... (Complete abstract click electronic access below)
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Villar, Luciene Dias. "Estudo da lixiviação bacteriana de metais presentes em lodo de esgoto sanitário /." Araraquara : [s.n.], 2003. http://hdl.handle.net/11449/100756.

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Orientador: Oswaldo Garcia Junior
Banca: Íria Fernandes Vendrame
Banca: João Sérgio Cordeiro
Banca: Rosana Filomena Vazoller
Banca: Maria Lucia Gonsales da Costa Araujo
Resumo: A geração de lodo como resultado do tratamento do esgoto sanitário, embora possa ser minimizada, é inevitável, qualquer que seja o sistema empregado nas estações de tratamento. Sua disposição final tem sido motivo de diversos estudos, os quais apontam, como alternativa mais favorável, sua utilização em áreas agrícolas ou de produção florestal. A presença de metais no lodo, entretanto, pode inviabilizar seu uso como fertilizante ou como condicionador de solos dado ao risco de contaminação ambiental e de acumulação na cadeia trófica. A solubilização de metais presentes no lodo por meio do processo de lixiviação bacteriana tem mostrado resultados promissores, encorajando seu desenvolvimento. A lixiviação bacteriana de metais pode ocorrer diretamente, pela oxidação de sulfetos metálicos ou, indiretamente, pela oxidação de compostos reduzidos de enxofre a sulfato, com a conseqüente solubilização ácida dos metais. As principais bactérias envolvidas nesse processo pertencem ao gênero Thiobacillus, recentemente reclassificado. Neste trabalho, utilizou-se lodo de esgoto, gerado pela Estação de Tratamento de Esgoto de Franca-SP (ETE-Franca), que opera um sistema de lodos ativados convencional, com tratamento dos lodos primário e secundário por digestão anaeróbia. Amostras de lodo foram caracterizadas quanto à presença dos metais cromo, cobre, chumbo, níquel e zinco. Em um ensaio preliminar, utilizando a linhagem Acidithiobacillus thiooxidans FG01, foi verificado que a utilização de lodo digerido ou lodo não-digerido proporcionou eficiências de solubilização similares para os metais investigados. Desta forma, amostras de lodo digerido anaeróbio foram utilizadas para estudo do efeito dos parâmetros temperatura, pH inicial e concentração de sólidos totais sobre a eficiência e a cinética da lixiviação bacteriana. Nesses ensaios,...(Resumo completo clicar acesso eletrônico abaixo)
Abstract: Although sewage sludge generation from sanitary wastewater treatment can be minimized, its production cannot be avoided at any system employed in the wastewater treatment facilities. Sludge final disposal has motivated several research studies, which have pointed out as the most suitable alternative the application of sludge in agricultural and forestry production. However, the presence of metals in sewage sludge may jeopardize its application as fertilizer or soil amendment due to the risk of environmental contamination or accumulation through the trophic chain. Solubilization of metals from sewage sludge by bacterial leaching has showed promising results, encouraging its process development. Bacterial leaching of metals occurs directly by metal sulphide oxidation or, indirectly by oxidation of reduced sulphur compounds to sulphate, with the consequent sludge acidification and metal solubilization. Bacteria from Thiobacillus genus, recently reclassified, are the most important species involved in bacterial leaching. In this work, sludge samples were obtained at the municipal wastewater treatment facility in the city of Franca, state of São Paulo, Brazil, which operates a conventional activated sludge system with treatment of the primary and secondary sewage sludges by anaerobic digestion. Samples were characterized for concentration of the metals chromium, copper, lead, nickel, and zinc. A preliminary assay was conducted by using Acidithiobacillus thiooxidans FG01, which resulted in similar solubilization efficiencies for digested or not-digested sludges. Effects of temperature, initial pH and total solids concentration were investigated in leaching experiments using anaerobically digested sludge inoculated...(Complete abstract, click electronic access below)
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Breda, Carlos Cesar. "Utilização de lodo de efluente doméstico : efeitos na produtividade agrícola e em alguns aspectos ambientais /." Botucatu : [s.n.], 2003. http://hdl.handle.net/11449/101745.

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Orientador: Iraê Amaral Guerrini
Banca: Wanderley da Silva Paganini
Banca: Simone Damasceno
Banca: Roberto Lyra Villas Boas
Banca: Jorge de Lucas Junior
Resumo: O objetivo deste trabalho foi avaliar os efeitos da aplicação do lodo de esgoto proveniente de uma pequena estação de tratamento, localizada na Fazenda Experimental Lageado, Faculdade de Ciências Agronômicas-UNESP, Botucatu, SP, Brasil, na produtividade agrícola e características de plantas de milho, bem como seus impactos nas características do solo e na qualidade da água drenada para o freático. O delineamento experimental foi constituído por blocos ao acaso, com parcelas subdivididas no tempo (Ensaios), num total de 6 tratamentos, 4 blocos e 4 ensaios, sendo T1 (testemunha, sem fertilização); T2 (10t ha-1 de lodo seco); T3 (20t ha-1 de lodo seco); T4 (30t ha-1 de lodo seco); T5 (40t ha-1 de lodo seco) e T6 (adubação mineral). Os ensaios foram assim definidos: E1 (cultivo de verão instalado em 11/2000); E2 (cultivo de inverno instalado em 06/2001); E3 (segundo cultivo de verão instalado em 11/2001) e E4 (segundo cultivo de inverno instalado em 05/2002). Foi utilizado o milho como cultura teste. Os parâmetros avaliados no campo foram altura das plantas, diâmetro do colmo e número de folhas em três épocas diferentes, além da análise foliar. Após a colheita das espigas foram avaliados os componentes de produção: massa sem palha, comprimento, diâmetro e número de fileiras das espigas; massa da palha; diâmetro... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The objective of this study was to evaluate the effects of the use of sewage sludge, coming from a small treatment station, located in Lageado Experimental Farm, Agronomic Sciences College - UNESP, Botucatu, SP, Brazil, on productivity and characteristics of corn plants, as well as its impact on soil characteristics and quality of drained water. The experimental design constituted of randomized blocks, with split plots in time (Assays), with 6 treatments, 4 blocks and 4 assays. The treatments were T1 (control, without fertilization); T2 (10t ha-1 of dry sludge); T3 (20t ha-1 of dry sludge); T4 (30t ha-1 of dry sludge); T5 (40t ha-1 of dry sludge) and T6 (mineral fertilizer). The assays were defined as: E1 (first summer plantation, installed in 11/2000); E2 (first winter plantation, installed in 06/2001); E3 (second summer plantation, installed in 11/2001), and E4 (second winter plantation, installed in 05/2002). The parameters evaluated were height of plants, stem diameter and number of leaves, besides leaves chemical analysis. After harvesting of corn spikes, the production components were evaluated: spikes without straw; spike length, diameter and line number; straw weight; corncob diameter; number of spikes; weight of 1000 grains and grains for spike). Moreover, the corn productivity at 13% of... (Complete abstract click electronic access below)
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Rufato, Fernando Henrique. "Efeito da redução do diâmetro interno sobre o desempenho de um reator aeróbio de leito fluidizado no tratamento de esgoto sanitário /." Ilha Solteira : [s.n.], 2005. http://hdl.handle.net/11449/90737.

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Orientador: Milton Dall'Aglio Sobrinho
Banca: Tsunao Matsumoto
Banca: Pedro Alem Sobrinho
Resumo: Os reatores de leito fluidizado com circulação em tubos concêntricos têm apresentado bons resultados no tratamento de esgoto sanitário, conforme uma série de relatos da bibliografia. Entretanto, o estado atual da modelagem não oferece ferramentas consolidadas para o projeto dos reatores deste tipo, devido à complexidade do funcionamento do leito trifásico e sua interdependência com os parâmetros biológicos envolvidos. Nesse contexto, a presente pesquisa teve por objetivo caracterizar experimentalmente os efeitos da redução do diâmetro interno sobre o funcionamento de um reator de 6 metros de altura, por meio de estudos hidrodinâmicos e análises laboratoriais do esgoto afluente e efluente. O reator tem diâmetro externo de 0,25m e foi operado anteriormente com um tubo interno de 0,20m de diâmetro, o qual foi reduzido para 0,10m neste trabalho. Antes de iniciar o tratamento foram medidas as velocidades de circulação por meio de injeção de traçadores e foram determinados os coeficientes de transferência de oxigênio. O tratamento do esgoto sanitário, submetido a gradeamento prévio, foi realizado com TDH de 3 horas e concentração de meio suporte de 100g/L de areia com diâmetro médio de 0,26mm. Os resultados indicaram que a redução do diâmetro interno provocou aumento expressivo da velocidade do líquido no tubo de subida. Com isso foi possível utilizar vazões de ar tão baixas quanto 1500L/h sem risco de instabilizar o leito, enquanto que na situação anterior eram necessários cerca de 3700L/h. O processo de tratamento foi o fator limitante da vazão de ar, requerendo cerca de 2100L/h. As remoções médias de DQO, DBO e NTK situaram-se em 91,1%, 88,5% e 88,8%, respectivamente. Com o diâmetro interno de 0,20m foram obtidas, em condições de operação semelhantes, remoções de 81,7%, 88,6% e 87,0%, com uma vazão de ar de 3700L/h. Com o tubo interno de 0,10m o reator apresentou bom desempenho hidrodinâmico, ...
Abstract: The circulating fluidized bed reactors with concentric tubes have been presented good results in the treatment of domestic wastewater, as shown by several reports in the literature. However, the current state of the art of modeling does not offer consolidated design tools to this kind of reactors, due to the complexities of the three-phase bed behavior and their interdependence with the biological parameters involved. In this context, the objective of this research is to experimentally characterize the effect of the internal diameter reduction on the functioning of a reactor with 6 meters of height, by means of hydrodynamic studies and laboratorial analyses of the reactor's affluent and effluent. The reactor has an external diameter of 0,25m and an internal tube with a previous diameter of 0,25m, reduced to 0,10m in this work. Before initiating the treatment the circulation velocities were measured by injecting tracers and the oxygen transfer coefficients were determined. The treatment of the previously screened wastewater was carried out with Hydraulic Detention Times (HDT) of 3 hours The solid phase (carrier particles) used was 100g/L of sand with 0,26mm of average diameter. The results indicated that the reduction of the internal diameter greatly increased the liquid's velocity in the riser. Thus it was possible to use air injection taxes as low as 1500L/h without risk of bed settlement, while in previous situations it was necessary about 3700L/h. The air flux of about 2100L/h required by the treatment process was the restraining factor to the diminution of the air injection flux. The averaged removals of DQO, DBO, and TKN were respectively 91,1%, 88.5% and 88.8%. With the internal diameter of 0,20m in similar conditions there were obtained removals of 81,7%, 88.6% and 87.0%, with an air injection flux of 3700L/h. With the internal tube of 0,10m the reactor presented good hydrodynamic performance, also improving the settling ...
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Chand, Rashmi. "Advanced oxidative wastewater treatment using cavitational reactors." Thesis, Abertay University, 2008. https://rke.abertay.ac.uk/en/studentTheses/fdce9629-7b22-43c6-9162-d03848e5df3b.

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This thesis explores various novel ways of treatment of wastewater contaminated by toxic organic pollutants using single and combined advanced oxidative wastewater treatment technologies in conjunction with a variety of acoustic and hydrodynamic cavitational reactors. There have been many reports in the literature on the use of hydroxyl radicals as the core part of AOPs and hence, as the first objective, the amount of hydroxyl radical generation from different acoustic and hydrodynamic cavitational reactors was studied using the potassium iodide dosimeter. The results reveal that optimum concentrations of less toxic chloroalkanes (chloroform and dichloromethane) could be efficient alternatives to carbon tetrachloride for enhancement of hydroxyl radical generation in cavitational reactors. Increasing ultrasonic amplitudes and operating hydrodynamic cavitational pressures lead to higher rates of hydroxyl radical production. Having explored the efficiency of generation of hydroxyl radicals the capacity of the reactors to degrade the model pollutant phenol, via a modified classic Fenton reaction which uses zero valent iron catalysts (instead of iron salts) and hydrogen peroxide under acidic conditions was studied. This process, named the advanced Fenton process (AFP), is the main foundation of the phenolic wastewater treatment reported in this thesis. Phenol degradation was assessed using different frequencies of ultrasound where a comparison between 20, 300 and 520 kHz ultrasonic reactors showed that 300 kHz was by far the most efficient US reactor resulting in 100% phenol removal and 37% total organic carbon (TOC) mineralization in 25 min. The concept of Latent Remediation (LR) was discovered during investigations into innovative approaches towards development of cost/energy-effective methods to treat phenolic wastewater. LR consists of inputting only 15 min of either ultrasound or stirring to the reaction medium, which contains optimised amounts of hydrogen peroxide and iron catalyst, and then the silent-dark AFP phenol degradation was studied over 24 h. The excellent results revealed that >80% TOC mineralization was achieved after this time. It was also found that zero valent copper catalysts were effective for phenol degradation and offered an excellent alternative to iron in the AFP, however toxicity analysis on the 24, 48 and 72 h samples showed that zero valent iron exhibited decreased toxicity when compared to zero valent copper. Conventional granular/powdered activated carbons were replaced with activated carbon cloth and investigations on the potential use of this material for phenol removal/decomposition was studied in detail at different operating pHs (3, 5.5 and 9), temperatures (20, 40 and 80 °C), oxidants (H2O2/O3) in various reactors (pump, shaker and US bath). Another aspect of the AOP application, disinfection of natural waters, was studied employing hydrodynamic cavitation and ozonation in a novel Liquid Whistle Reactor system. Model markers of faecal coliforms, Escherichia coli, were chosen for the study and the combined technologies of hydrodynamic cavitation and stepwise ozonation proved be highly beneficial, resulting in ~ 6 log bacterial reduction revealing 99.9999% disinfection efficiency of the process.

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Wong, Tak Ian. "Numerical flow simulations of an egg-shaped anaerobic sludge digester in wastewater treatment /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?EVNG%202005%20WONG.

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Abubakar, Umar Alfa. "A technological model for low energy domestic wastewater treatment." Thesis, Abertay University, 2015. https://rke.abertay.ac.uk/en/studentTheses/51ee0b9e-808f-441e-8420-c2276cccbf48.

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This study evaluated the potential for efficient treatment of domestic wastewater, while satisfying energy efficiency requirements. Various treatment systems and the influences of their physical configurations and operational characteristics on wastewater treatment and energy efficiency were initially considered and evaluated. Review of literature identified high rate anaerobic systems as viable low energy systems for domestic wastewater treatment, with reported high removal of influent chemical oxygen demand (COD) and high net energy balance for the anaerobic baffled reactor (ABR). Low energy recovery is reported in literature as a limitation of anaerobic domestic wastewater treatment, and anaerobic domestic wastewater treatment systems have failed to meet effluent discharge standards, and post-treatment using aerobic processes have been recommended in order to ensure high effluent quality. Therefore, the ABR was selected as a feasible option that can be developed as the first stage of an anaerobic-aerobic low energy domestic wastewater treatment system. The literature review also identified the net energy consumption per cubic metre (m3) of treated wastewater during the treatment process as an energy efficiency evaluation criterion. Energy efficiency for domestic wastewater treatment facilities should be achieved if efficient treatment performance can be sustained at ambient temperature, instead of the fixed mesophilic temperature that is commonly adopted in anaerobic treatment processes. To identify an energy efficient design of the ABR in terms of hydraulic retention time and operational temperature, the performance efficiencies of ABR bench models were monitored at ambient temperature and 37oC at hydraulic retention times (HRT) of 48, 36, 24, 12 and 6 hours, which corresponded to organic loading rates (OLR) of 1.25, 1.67, 2.5, 5.0 and 10.0 kg COD/m3 day. 88.43, 90.00, 84.03, 77.01 and 59.35% of the influent COD (mean = 2479.50 mg/L) were removed at 48, 36, 24, 12 and 6 hour HRTs, respectively, in the 37oC bench reactor, while 70.16, 70.36 and 74.99% of the influent COD were removed at 48, 36 and 24 hour HRTs, respectively, in the ambient temperature bench reactor. Steady state performance, in the form of stable pH values, was not observed in the ambient temperature reactor at 12 hours HRT before the end of the bench experiments. Retention of influent total solids was observed to correlate to hydraulic retention time, with increase retention of total solids corresponding to increase in hydraulic retention time. Furthermore, observed total solids retention in the ambient temperature reactor were less than the total solids retention in the 37oC reactor. Anaerobic reduction of domestic wastewater sludge and the corresponding methane production were also evaluated using bio-chemical methane potential (BMP) batch assays at ambient temperature and compared to a fixed mesophilic temperature of 37oC. Low reduction of volatile solids was observed in the BMP assays, with 40% at ambient temperature compared to 56% at 37oC for primary sludge, and 22% at ambient temperature compared to 38% at 37oC for secondary sludge. Critical limitations of the anaerobic stage at ambient temperature were determined to be the biological reduction and conversion of the organic contaminants to soluble COD and volatile fatty acids (VFA). Also, achieving and maintaining steady state performance required a longer time period at ambient temperature than at 37oC, potentially due to the slow growth of the anaerobic microorganisms at ambient temperature. These limitations indicate the need for long (≥ 24 hours) retention periods for efficient operation at ambient temperature. The ABR bench models were evaluated for energy efficiency with the identified energy efficiency criteria, and the operational condition with the highest energy efficiency was determined to be 12 hours HRT at 37oC. Finally, design criteria for the anaerobic stage of the anaerobic-aerobic system were proproposed, along with a process model as a preliminary step for future process research.

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Ng, Chi Po. "Treatment of textile wastewater by combined photo-fenton and biological process /." View abstract or full-text, 2005. http://library.ust.hk/cgi/db/thesis.pl?EVNG%202005%20NG.

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Guwy, Alan. "Monitoring the stability of anaerobic digestion using a novel on-line bicarbonate alkalinity monitor." Thesis, University of South Wales, 1995. https://pure.southwales.ac.uk/en/studentthesis/monitoring-the-stability-of-anaerobic-digestion-using-a-novel-online-bicarbonate-alkalinity-monitor(8e1dff8e-1f72-480a-b22d-b241e557501f).html.

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In many biological reactors' bicarbonate ions are the major species determining pH buffering capacity, or alkalinity. In anaerobic digesters the bicarbonate levels should be within 10 to 50mM to ensure stable operation. Bicarbonate concentration in wastewater treatment processes is routinely measured off-line by titration with standard acid to a set pH value. However along with the bicarbonate/carbonate system, the phosphate, ammonia, sulphides and volatile fatty acids systems are present in anaerobic process. These systems can exert a significant influence on the accuracy of bicarbonate titration's to a set pH. An overload of 4.7 to 13.6 kgCODm-3d-1 1 administered to a 5m3 pilot scale anaerobic filter reactor showed that bicarbonate alkalinity, measured off-line by titration responded rapidly to the organic overload, decreasing by 10% after only 1 hour of the overload initiation. The propionic acid concentration (often regarded as the best indicator of instability in anaerobic digestion) increased from 170ppm to 190 ppm in the same period, which corresponds to an increase of 12%. At present the use of anaerobic digestion as a waste treatment method is partly limited because of the lack of reliable control procedures. This thesis introduces a simple on-line instrument for direct determination of bicarbonate concentration especially for automatic control of anaerobic digesters. The proposed method is based on a continuous flow rate measurement of carbon dioxide evolved from a continuous stream of sampled (<15cm3min-1 ) solution after saturation with gaseous C02 and subsequent acidification with excess acid. Measurement of bicarbonate in this way eliminates the interferences of the phosphate, ammonia, sulphides and volatile fatty acids systems and removes the need for a pH probe which are subject to fouling.

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Dias, Edgard Henrique Oliveira. "Bacteriophages as surrogates of viral pathogens in wastewater treatment processes." Thesis, University of Brighton, 2016. https://research.brighton.ac.uk/en/studentTheses/9606c027-b1ad-4204-91e2-b906a842e888.

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Although wastewater reuse presents numerous benefits, wastewater-borne pathogens, especially human enteric viruses, may pose risks to human health. Wastewater treatment processes have been shown to remove bacterial pathogens more effectively than they do viral pathogens, and in aquatic environments, levels of traditional faecal indicator bacteria (FIB) do not appear to correlate consistently with levels of human viral pathogens. There is, therefore, a need for novel viral indicators of faecal pollution and novel surrogates of viral pathogens. Potential candidates for this role include enteric bacteriophages (phages), viruses capable of infecting enteric bacteria.

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Jack, Andrew G. "Total emission analysis of sewerage systems and wastewater treatment plants." Thesis, Abertay University, 1999. https://rke.abertay.ac.uk/en/studentTheses/3a4ee741-9f14-47df-ab48-2759ca7c39f3.

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The proposed methodology to most effectively manage intermittent combined sewage discharges into urban watercourses in the UK is given in the Urban Pollution Management (UPM) manual. The method is based on the use of detailed computer models of the sewerage system, wastewater treatment plant and receiving watercourse. Solving intermittent discharge problems using UPM, often requires the installation of in-sewer storage tanks. However, recent research from Germany and elsewhere (e.g. Austria and Denmark) has shown that this type of solution may be of little benefit with respect to the total emissions discharged from the entire system, where emissions from both the Combined Sewer Overflows (CSOs) and the Wastewater Treatment Plant (WTP) are considered together. This is because, in certain situations, WTP efficiency can be compromised by the prolonged periods of dilute (low nutrients and substrate) inflows which can result from the draining down of in-sewer storage tanks. The earlier research in Germany and elsewhere has been concerned with long term total emissions (annual loads) and not the problems specific to individual sites, or the benefits and/or limitations of storage with respect to acute pollution. Thus the principal objective of the research described here has been to substantiate and quantify the total emission problem by means of detailed modelling, via an evaluation of the likely storage volumes which could give rise to total emissions problems for the Perth wastewater system. Following this, a general method has been developed to investigate and resolve total emission problems related to acute pollution effects. As WTP disruption due to flow dilution can last for a prolonged period after even a single rainfall event, computational simulation times need to be long enough to represent the delay in WTP performance returning to normal operating conditions. As long term continuous simulation is usually impractical due to protracted computational times, a method referred to as the Total Emission Analysis Period (TEAP) has been developed. This will define the minimum required computational time and rainfall inputs to be used to ensure that the effect of in-sewer storage on total emissions could be modelled. Utilising the TEAP method to analyse total emissions it has been concluded that increasing volumes of storage would not be expected to create a total emission XXVI problem with respect to the Biochemical Oxygen Demand (BOD). Consequently, it was concluded that the best storage volume with respect to BOD was the minimum volume which would allow compliance with receiving water quality standards. No direct comparison could be made with the conclusion derived from the German research due to the long term nature of their analysis, however, it would appear from an interpretation of their results, that similar findings were obtained. With respect to ammonia, it was found that increases in total emissions can occur as, ammonia concentrations, unlike BOD, do not increase at the start of a storm due to first foul flush effects. Consequently, any increased emissions from the WTP would not be offset via a reduced CSO spill load. It was also found, however, that increasing volumes of storage would not be expected to exacerbate acute pollution problems within a receiving watercourse and that both large and small storage volumes had the potential to give rise to very similar degrees of WTP disruption. This was due to the way in which different hydraulic loading conditions (caused by the different volumes of storage) affected the bacterial concentrations in the reactor. The conclusion that storage would not provide a significant benefit for ammonia total emissions was supported by the Austrian and Danish research.

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Murray, Simon Thomas. "Applications of membrane aerated biofilm reactors for wastewater treatment." Thesis, Queen's University Belfast, 2016. https://pure.qub.ac.uk/portal/en/theses/applications-of-membrane-aerated-biofilm-reactors-for-wastewater-treatment(af60a6ed-09b7-4b95-8730-d3de83b3876e).html.

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Despite being the subject of peer reviewed research since the mid-1980s, the conservative nature of the wastewater treatment industry means that the commercial application of membrane aerated biofilm reactors has not realized the potential that the published research demonstrates. The early research demonstrated the ability of membrane aerated biofilm reactors to achieve good levels of pollutant removal from various types of wastewater, but also exposed several weaknesses of the technology (i.e. cost of membranes, control of biofilm thickness) which have prevented the concept of MABfRs being developed in viable wastewater treatment technologies. However, as membrane technology has developed, the cost of suitable membranes has fallen, prompting the research community to revisit the concept. This later batch of research has identified several niche applications where membrane supported biofilms can be used for effective removal of pollutants from water. Using the MABfR for the treatment of secondary effluent as a polishing step is another niche application which has been identified and is examined in this work; leading to the development of a patented treatment technology – the BioSettler.

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Cooksey, Emily. "Development of microbial fuel cells for the treatment of wastewater." Thesis, University of Manchester, 2018. https://www.research.manchester.ac.uk/portal/en/theses/development-of-microbial-fuel-cells-for-the-treatment-of-wastewater(b53cc17f-51ef-46b5-b361-46cf1f64f920).html.

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The aim of this study was to develop a microbial fuel cell (MFC) wastewater treatment system with a reduced production of sludge; whilst generating electricity as a product. Addition of a graphite intercalated compound, Nyex, provided an opportunity to add an adsorbent system for removal of micropollutants and dyes. Electrochemical analysis, effluent analysis and biofilm analysis provided detail on power generation and wastewater treatment ability and understanding of the biofilm. An 800ml capacity two-chamber MFC was developed and operated using anaerobic wastewater sludge as the anodic inoculum, acetate based artificial waste water as an anolyte and buffered DI water as a catholyte. Separation was provided by a proton exchange membrane, Nafion 117. Nyex was incorporated into the base design using 6 different configurations. Of those, the system with 100g of Nyex loose around each electrode saw the best overall performance. Producing a maximum power density of 0.054W m-2 and current density of 0.35A m-2, an increase of 500% and 312%, respectively, compared to the base fuel cell after 60 days of operation. This is due to a reduction in internal resistance of 86%. Scanning electron microscopy of biofilm indicated species rapidly form links between electrode material to facilitate electron transfer. 16s rRNA gene analysis of used anodic biofilm in the base fuel cell identified two dominant species; P,putida and P.caeni, neither had been used as a pure MFC inoculum. When used as pure cultures and in binary combination all MFCs generated voltage, indicating the species are exoelectrogenic. P.putida produced a current density of 0.0179A m-2, a 258% increase on P.caeni alone, 99% increase on the binary inoculum and a 49% increase on the mixed sludge used for the same time period in the same cell setup. Its maximum power density was 0.0018W m-2; a 167% increase on P.caeni, a 157% increase on the binary inoculum and a 100% increase on the mixed sludge inoculum. COD removal saw a decrease of 62.2% for P.caeni, 61.6% for the binary inoculum, 50.8% for P.caeni, treating 400mL of feed and 34% for the mixed culture treating 1L of feed during the same time period with the same maturity. Based on the results of this study, using the Nyex fuel cell with loose Nyex on both sides generates a power density of 0.054W m-2 when treating 1L of artificial wastewater. Using this system to treat the 11 billion litres of wastewater generated in the UK everyday [1] would result in a total power output of 9.5MW per day. Assuming that the benefits of modifying the fuel cell configuration and modifying the biofilm are independent, their improvements on cell performance can be assumed to be cumulative. Therefore, taking the 0.054W m-2 from the mixed culture Nyex cell and accounting for the 100% power density improvement when using P.putida, the potential power density is 0.108W m-2. Which when applied to the 11 billion litres of wastewater being treated daily within the UK would produce a total power output of 19MW per day.

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Mohammad, Hussain. "Advanced oxidation for wastewater treatment by adsorption with electrochemical regeneration." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/advanced-oxidation-for-wastewater-treatment-by-adsorption-with-electrochemical-regeneration(b71e7a8f-8379-4c27-b2ef-826b833549b2).html.

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This thesis investigates an innovative advanced oxidation process that has been developed to use adsorption combined with electrochemical regeneration. The process uses a graphite based adsorbent material, which enables low cost electrochemical treatment of wastewater. The work in this thesis was carried out to study the effect of electrochemical regeneration on the liquid, solid, and gaseous phases. This project investigates the fate of organic pollutants during the wastewater treatment process by analysing the gases produced, the adsorbent material and the water treated. This study evaluates the removal process under different operational parameters based on the pollutant reduction in the liquid phase and adsorbent regeneration efficiency. In addition, the relationship between adsorbent Nyex1000 and reaction products in the gaseous phase is important to indicate the source of gaseous products and lifetime of adsorbent Nyex1000.The process of adsorption and electrochemical regeneration was conducted using adsorbate acid violet 17 and phenol. Effect of electrochemical regeneration over adsorbent Nyex1000 solid phase was determined using scanning electron microscope, time-of-flight secondary ion mass spectrometry, and atomic force microscopy. This technique of solid analysis was also efficient in determining penetration level of pollutant in the solid phase. The study of solid surface chemistry was also essential to determine favored active sites supporting the adsorption process. C13 labelled phenol contaminant was used so that the distribution of carbon from adsorbent Nyex1000 to that from adsorbate. It was observed that electrochemical regeneration achieved regeneration efficiency over 100% by oxidising not only loaded contaminant but also the surface of adsorbent Nyex1000. The process of electrochemical regeneration was found dependent on both adsorbent initial concentration and charge passed. For solid phase analysis, results agreed with Lagergren 2nd order kinetics that adsorption process was achieved based on chemical bonds between adsorbate and active site at adsorbent surface. In addition, carbon balance between adsorbent phenol and gaseous product represented by carbon monoxide and carbon dioxide recorded in the range of 41-52% carbon recovered indicated other oxidation route with respect to phenol oxidation. Moreover, using C13 labelled phenol indicated that applied charge is being consumed partially in oxidising both adsorbent Nyex1000 surface and adsorbate C13 labelled phenol with a range of 70-80% charge consumption towards adsorbent Nyex1000 oxidation.

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Quinta, Raquel Figueiredo. "Effectiveness of halophytic plants in the treatment of marine aquaculture wastewater." Thesis, Bangor University, 2013. https://research.bangor.ac.uk/portal/en/theses/effectiveness-of-halophytic-plants-in-the-treatment-of-marine-aquaculture-wastewater(cb882934-8bfc-4f84-87bc-59ed98c7d184).html.

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This study aims to assess the overall efficiency of S. europaea and A. tripolium plants in wastewater treatment in saline aquaculture systems (IMTA), while generating a valuable secondary crop. Specifically plant N uptake and/or biomass production under different N concentration and forms, salinity, irradiance, temperature and cropping regimes are investigated. It is estimated that at a constant supply of ≥ 300 μmol NO3- l-1 S. europaea N removal of 65.3 ± 18.1 mmol N plant-1 can be achieved over one growing season. Plant growth in a non N limited hydroponic system, with or without a repeated harvest regime, showed that uncropped plants accumulated more fresh biomass than cropped (S. europaea 34 kg m-2 and 17 kg m-2, A. tripolium 21 kg m-2 and 10 kg m-2, respectively). N removal is closely related to plant biomass, and therefore the repeated harvesting can reduce N removal, however it provides a regular high value product for marketing. S. europaea showed better growth when supplied with NO3- or NH4NO3, comparing to NH4+, while A. tripolium growth was not affected by the form of N. The measured A. tripolium and S. europaea DIN uptake, as NH4+ and NO3-, when supplied separately or in an equimolar mix were in general good fits to the Michaelis-Menten model. NH4-15N uptake rates are higher than NO3-15N uptake, except in non-starved S. europaea for single N forms supplied alone. Inhibition of NO3-15N uptake by the presence of NH4+ in solution was observed in non-starved plants. S. europaea responds negatively to salinity 1 compared to 10 and 30, while A. tripolium responds negatively to salinity 30, indicating the suitability of both plant species to be used in systems with middle range salinities, but preference for S. europaea over A. tripolium at higher salinities and vice versa. DIN uptake in both plant species increased linearly with increasing irradiance, and was higher at the mid-range of temperatures tested (20-40 °C). Differences in N uptake with varying environmental conditions needs to be further investigated and taken in account when designing the treatment system. S. europaea and A. tripolium were shown to uptake organic N at comparable rates to DIN uptake, and when in solution more than 68% of organic N uptake was as intact alanine and trialanine indicating the potential of these plants to directly remove DON from the wastewater. Overall the results obtained indicate that S. europaea and A. tripolium are able to perform well in IMTA, with efficient N removal and high biomass production. The data obtained provides a sound basis for system design and scaling up.

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Watkins, Siobhan. "Physico-chemical and microbial factors affecting the operation of a package wastewater treatment plant." Thesis, University of Portsmouth, 2011. https://researchportal.port.ac.uk/portal/en/theses/physicochemical-and-microbial-factors-affecting-the-operation-of-a-package-wastewater-treatment-plant(964c4c5f-6456-421a-8d8f-b949ea9ef6f8).html.

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The Biologically Engineered Single Sludge Treatment (BESST) system is a small package wastewater treatment plant, which is designed to reduce influent concentrations of ammoniacal nitrogen, biochemical oxygen demand and total suspended solids, to a standard fit for discharge into controlled waterways. This thesis examines the treatment performance of the BESST, while operating under steady state and disruptive conditions, and assesses the contribution of physicochemical and microbiological factors to treatment efficacy. The design of the BESST was based on principles of activated sludge processes, and comprised of an anoxic area, an aerobic area, and an upflow clarifier. In each area of the system, physico-chemical and microbiological profiles were distinct from the other areas. The influent delivered to the system was municipal sewage, delivered from the start of the wastewater treatment works within which the prototype BESST was located. The influent was generally high in concentrations of biochemical oxygen demand, and was highly variable in nature. At times, this was reflected in effluent quality, particularly when disruptive events were occurring, such as mechanical failure. However, good levels of reduction in concentrations of ammoniacal nitrogen, biochemical oxygen demand and total suspended solids were observed throughout the treatment period, and the system demonstrated a good level of robustness with regard to mechanical failure and experimental changes to sewage control parameters. Transformations of nitrogen and phosphorus were performed by bacteria in the biomass of the system, and were analysed throughout the sampling period by qualitative, culture based and molecular microbiological methods. Culture based techniques were shown to be a valuable monitoring tool, but were not representative of the actual community in the BESST. Molecular methods provided a higher resolution of microbial populations present during treatment, but it was not possible to correlate data obtained from culture based methodology with that obtained using molecular techniques. Enhanced phosphorus removal trials were performed during the study period, in order to facilitate the production of an effluent very low in concentrations of total phosphorus. The trial suggested that enhanced removal of phosphorus was possible in the BESST, and found the most dominant morphotype accumulating polyphosphate, to be that of filamentous bacteria. The study produced a large and complex dataset, which presented difficulties in the analysis of interactions between variables. Suggestions are presented to overcome such difficulties. The BESST is presented in this study as a package wastewater system which is able to successfully perform biological nutrient removal in a robust manner, the interrogation of which has led to a greater contribution to knowledge of small wastewater treatment systems and the reactive nature of the chemical and biological processes occurring within them.

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Boghani, Hitesh Chandubhai. "Systems approaches to enhance performance and applicability of microbial fuel cells." Thesis, University of South Wales, 2014. https://pure.southwales.ac.uk/en/studentthesis/systems-approaches-to-enhance-performance-and-applicability-of-microbial-fuel-cells(80a19e1c-fd40-42de-90cd-8b6ebcbb73d7).html.

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Wastewater treatment is an energy intensive process and sustainable processes/technologies for the treatment of wastewaters need to be considered. One such contender might be the microbial fuel cell (MFC), a subset of bioelectrochemical system (BES) which generates electricity in the process of electrogenic (generating electrons) degradation of soluble organic contaminants present in the water (or wastewater) by electrogens (electron producing bacteria) at the anode in absence of oxygen. Several issues related to the power performance (also somewhat linked to the cost) of MFCs exist causing barriers in the deployment of up-scaled MFC system and the continual research from a multitude of discipline is focusing on overcoming these issues. Implementation of an MFC system for wastewater treatment would require a large array of MFCs to meet the treatment capacity of the wastewater treatment plant. Commissioning and continual operation of such MFCs would require rapid and cost-effective start-up and improvement in their performance. Optimisation of the power performance is addressed through a systems approach in this study, where improvement in the performance is sought through the system design and control strategies applied to the MFCs. The start-up rate of MFCs has been reduced by 45% using maximum power point tracking (MPPT), which is believed to be cost-effective as exogenous energy (such as in the case of poised-potential) is not required for the rapid start-up. The control of MFC power would need to be considered when up-scaled MFC system is realised. The controller implementation benefits from linearised system models. The viability of such piecewise linearisation of the nonlinear MFC system was demonstrated and the data were shown to be reasonably represented by the 1st order process models throughout its operating range. The occurrence of voltage reversal during stack operation of MFCs is a concern in large arrays particularly, and has been shown to be avoidable by adopting the hybrid stack connectivity. Further enhancement of the performance was sought through the detailed design and fluid dynamics modeling to obtain highly mixed anolyte at low input power, using improved helical anodes which increased the MFC performance at all the tested flow rates (1, 3 and 8 mL min-1) compared to previously studied helical anodes. The up-scaling of MFCs by modularisation was demonstrated and it was shown that the use of improved helical anodes can increase the modular length of the MFC without compromising the power performance. Aggregated power produced from the multi-module MFC (containing 5 modules) was 28.05 ± 3.5 mW (19.75 ± 2.47 W m-3) with an PhD Thesis – Hitesh Chandubhai Boghani 2014 V individual MFC power of 5.61 ± 0.7 mW, when fed with 10 mM sodium acetate at 3 mL min-1 flow rate and at 22 ± 3 °C. So, this thesis presents the strategies for improvement in the performance of MFCs for their applications in wastewater treatment and such strategies may also be transferable to their other applications.

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Maja, Sremački. "Modules of emerging xenobiotics detection in mixed urban wastewater." Phd thesis, Univerzitet u Novom Sadu, Fakultet tehničkih nauka u Novom Sadu, 2017. https://www.cris.uns.ac.rs/record.jsf?recordId=104979&source=NDLTD&language=en.

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Emerging substances of concern (EmS) are wide groups of chemicals frequently used, that are not included in legislation nor mandatory monitored like priority and hazardous priority substances. Group of substances overlapping in priority and emerging substances list provided by legislation are Endocrine Disruptive Compounds (EDCs), referred to as emerging xenobiotics (EXs). The modules of emerging xenobiotics detection and identification presents an interactive, complex and dynamic process shown in the research. Analytical method, LLE followed by GC-MS was successfully adapted and applied to screening of emerging and priority substances in wastewater. The screening and target analyses results were evaluated via risk assessment (ERA) and detected substances chemical properties were statistically evaluated (PCA, HCA an PC) for the purpose of correlation of chemical properties and predicted treatment possibilities from wastewater.
Емергентне супстанце (ЕмС) припадају широј групи хемикалија које се фреквентно користе, а нису обухваћене законски прописаном мониторингу, као приоритетне и хазардне приоритетне супстанце. Емергентни ксенобиотици (ЕК), а посебно супстанце које ометају ендокрини систем (ЕД), су група једињења које припадају и приоритетним и емергентним супстанцама. Модули одређивања ксенобиотика су интерактиван, сложен и динамичан процес, подложан променама, детаљно описан у тези. Аналитичка метода, ТТЕ праћене ГЦ-МС, успешно је прилагођена за скрининг идентификацију емергентних и приоритетних супстанци у отпадној води. За евалуацију добијених резултата коришћене су статистичке методе (ПЦА, ХЦА и ПК) у сврху корелације хемијских карактеристика са предвиђеним третманима отпадних вода, као и процена ризика за животну средину.
Emergentne supstance (EmS) pripadaju široj grupi hemikalija koje se frekventno koriste, a nisu obuhvaćene zakonski propisanom monitoringu, kao prioritetne i hazardne prioritetne supstance. Emergentni ksenobiotici (EK), a posebno supstance koje ometaju endokrini sistem (ED), su grupa jedinjenja koje pripadaju i prioritetnim i emergentnim supstancama. Moduli određivanja ksenobiotika su interaktivan, složen i dinamičan proces, podložan promenama, detaljno opisan u tezi. Analitička metoda, TTE praćene GC-MS, uspešno je prilagođena za skrining identifikaciju emergentnih i prioritetnih supstanci u otpadnoj vodi. Za evaluaciju dobijenih rezultata korišćene su statističke metode (PCA, HCA i PK) u svrhu korelacije hemijskih karakteristika sa predviđenim tretmanima otpadnih voda, kao i procena rizika za životnu sredinu.

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Tarpani, Raphael. "Sustainability assessment of wastewater and sludge treatment techniques for removal of compounds from Pharmaceuticals and Personal Care Products (PPCPs)." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/sustainability-assessment-of-wastewater-and-sludge-treatment-techniques-for-removal-of-compounds-from-pharmaceuticals-and-personal-care-products-ppcps(91f7fe09-e0f0-4560-924f-15d5725e0794).html.

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Environmental releases of chemical compounds from Pharmaceuticals and Personal Care Products (PPCPs) are receiving growing attention in the scientific community. Most research suggests that the main pathway for these substances to reach the environment is via Wastewater Treatment Plants (WWTPs) due to the effluents from households, industry and hospitals, which can contain substantial amounts of these compounds. Many of these contaminants are poorly treated in conventional WWTPs and are often discharged into the environment with the effluent and sludge, posing ecotoxicological risks to the wildlife and humans. Therefore, it is necessary to limit their release into the environment by controlling their discharge from WWTPs. This can be achieved by adopting advanced wastewater treatment techniques, currently not used as there are no legislative limits on PPCP compounds. However, as the scientific evidence is growing on their adverse impacts, it is only a matter of time before their advanced treatment becomes compulsory. To help guide future developments and inform policy in this area, this work considered a range of advanced treatment techniques with the aim of identifying the most sustainable options. Adopting a life cycle approach and considering all three dimensions of sustainability (economic, environmental and social), nine technologies were assessed on sustainability: four for WWTP effluent and five for sludge treatment. The advanced wastewater treatment methods considered are: (i) granular activated carbon, (ii) nanofiltration, (iii) solar photo-Fenton, and (iv) ozonation. The sludge treatment techniques comprise: (i) anaerobic digestion of sludge for agricultural application; (ii) sludge composting, also for agricultural application; (iii) incineration; (iv) pyrolysis; and (v) wet air oxidation. They were assessed on sustainability using over 28 indicators, some of which were also used to evaluate the implication of different treatment techniques for the energy-water-food (EWF) nexus. Multi-Criteria Decision Analysis (MCDA) was applied to aggregate the sustainability indicators into an overall sustainability index for each alternative and identify the most sustainable option(s). The results suggest that, among the four techniques considered for advanced effluent treatment, nanofiltration and granular activated carbon have the lowest life cycle environmental impacts. Although not preferable at all operating ranges, they have the lowest burdens and are, overall, most sustainable. The latter also has the lowest impact on the EWF nexus at mean operating parameter, and is the preferred option as the treated effluent can be used for potable water due lower concerns over the presence of PPCPs. However, the results also suggest that, from the ecotoxicological point of view, there is little benefit in using any of the advanced wastewater treatment techniques assessed. This is due to the life cycle ecotoxicological impacts from the treatment itself being similar or even higher than for the effluent released into the environment untreated. For sludge treatments, anaerobic digestion and pyrolysis are environmentally and economically preferable techniques. The former is the best with respect to the EWF nexus due to the recovery of energy and agricultural fertilizers. In relation to social aspects, wet air oxidation is amongst the most desirable for high resource recovery, together with the two former techniques. The heavy metals content in the sludge applied on agricultural soils is a major concern for freshwater ecotoxicity potential, posing risks orders of magnitude higher than PPCP compounds.

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Richards, Samia. "On-site wastewater treatment systems as sources of phosphorus and other pollutants in rural catchments : characteristics and tracing approaches." Thesis, Bangor University, 2017. https://research.bangor.ac.uk/portal/en/theses/onsite-wastewater-treatment-systems-as-sources-of-phosphorus-and-other-pollutants-in-rural-catchments-characteristics-and-tracing-approaches(cf2d6620-06b2-4737-8626-c6b736717585).html.

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This thesis investigated the influence of septic tanks (ST) on stream water quality. Characterisation of septic tank effluent (STE) revealed that STE were enriched in phosphorus (P), nitrogen (N), organic matter (OM) and metals relative to stream waters and large proportions of these parameters were present in the soluble reactive forms. Human factors such as tank design, number of users, dishwasher use and infrequent desludging significantly (P < 0.05) influenced effluent quality. ST that received roof runoff had reduced effluent retention time, while infrequent desludging was linked to increased OM, bacteria and P concentration in the effluent. Tanks that served larger numbers of people had elevated microbial abundance, P and N concentrations. Effluent composition was not consistent throughout the year, but exhibited similarity in warmer drier months that was different from effluent in colder wetter months for biological oxygen demand and heavy metals. Effluent attenuation in a test soil revealed that 14%-35% of P was attenuated by sorption processes, while saccharin was strongly attenuated by soil microbial degradation. The complex composition of STE reduced the ability of the test soil to adsorb P, as other substances in the effluent were competing for soil binding sites. Calculated P annual loadings from STE were 0.797 and 0.956 kgP/person/year for water usage of 150 and 180 l/person/day, respectively, while, effluents P load from detergents was 0.154 kg P/person/year. Newly developed tracing studies showed that ratios of chloride to other effluent indicators (e.g. EC, NH4-N, TSS, turbidity, total coliforms, sucralose, saccharin and Zn) and the detection of effluent tryptophan-like peak by fluorescence spectroscopy may be useful in tracking effluent discharge to streams with low levels of dilution. However, effluent caffeine and saccharin were more effective tracers in streams with low and high levels of dilutions. A single individual tracer alone was not sufficient to evaluate STE contamination sources, but combined chemical and physical tracing approaches show promise as tools to identify STE inputs that continue to pose risks to watercourses and where mitigation measures could be effectively targeted.

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Al-Nasri, Salam Khudhair Abdullah. "Treatment of wastewater containing cobalt (Co-59) and strontium (Sr-89) as a model to remove radioactive Co-60 and Sr-90 using hierarchical structures incorporating zeolites." Thesis, University of Manchester, 2015. https://www.research.manchester.ac.uk/portal/en/theses/treatment-of-wastewater-containing-cobalt-co59-and-strontium-sr89-as-a-model-to-remove-radioactive-co60-and-sr90-using-hierarchical-structures-incorporating-zeolitesa(ff5cff3e-1366-4a35-9b15-0246811d6ad1).html.

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Zeolites were used in this study to remove two types of non-radioactive ions (Cobalt-59 and Strontium-89) from wastewater. This was designed to model the use of ion-exchange technique to remove radioactive Co-60 and Sr-90 from low level wastewater from Al-Tuwaitha site. Al-Tuwaitha site is a nuclear research in Iraq was used for radio-medical and radio-chemical purposes before 1990. In this study, hierarchical microporous/macroporous structures were developed to overcome the diffusivity problem using zeolite. Diatomite and carbon were used to prepare the composite adsorbents by incorporating them with three types of zeolites (A, Y and clinoptilolite). From the XRD, SEM and EDAX measurement it was confirmed that successfully prepared of Iraqi palm tree leafs-Clinoptlolite (IPClinp) and Tamarind stones-Clinoptilolite (TSClinp) composites were obtained in this study as there is no evidence in literature of this being carried out before. The carbons were prepared successfully through the Pyrolysis method for 2h at 900°C in an inert atmosphere from two types of raw waste plant materials of Iraqi Palm Tree leafs (IP) and Tamarind stones (TS). For both types of carbons, the SEM images show organised porosities in different shapes. A third material used as a zeolite scaffold was diatomite (Celatom FW-14) a readily available natural material (dead algae).A hydrothermal treatment was used to build the hierarchical structure of zeolite onto carbon and diatomite materials, the scaffolds were seeded with nano-zeolite crystals prior to the treatment and thereafter mixed with the zeolite gel composition mixture in a stainless steel autoclave. Zeolite seeds were prepared using ball mill method to reduce the particle size of the commercial zeolite to sub-micron range for each type of zeolite. The surface area, morphology, element compositions and structure for each type of zeolite and composite material were characterised using BET method, SEM, EDAX and XRD. The amounts of each type of zeolite on the carbon composites were determined using TGA while that of the diatomite composite was determined by gravimetric analysis. The results show that each type of zeolite was successfully deposited and uniformly organised onto the surface of all support materials. All pure zeolites and composite materials were successfully tested to remove Co2+ and Sr2+ ions from aqueous solutions. It was found that the composite materials had higher ability to remove both ions relative to the pure zeolites. This increase is attributed to the deposition of zeolite (microporous) onto the macroporous structure (carbon and diatomite) which increased the flow accessibility within zeolite in the hierarchical structured composites. Comparison of the removal between the two metal ions indicates that all of the materials had higher uptake for Sr2+ than Co2+ ions. The highest adsorption capacities were realised with Tamarind Stone–ZeoliteA (TSA) in the order 120mg.gz-1and 290mg.gz-1 for Co2+ and Sr2+ ions, respectively. The effect of the experimental variables shows increasing uptake with increasing pH and initial ion concentrations while it decreased with increasing the solution temperature. The Co2+ loaded composites was subjected to vitrification process at 12000C for 2h. The encapsulated composites were leached for 90 and 120 days and no significant Co2+ was recorded in the leached solution. The results show that the composite materials can be used effectively to remove the radioactive ion of Co-60 and Sr-90 ion as they display the same chemical behaviour as Co-59 and Sr-89 studied in this work.

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Olsson, Michael Paul. "Upgrading aerated lagoons for the treatment of egg processing wastewater." Thesis, 1995. http://hdl.handle.net/2429/3668.

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The treatment of egg processing wastewater is typically accomplished in an aerated lagoon. However, to meet current wastewater guidelines, processing facilities must upgrade their systems. Without changing the dimensions of the system and without installing liquid-solid separation, upgrading to an sequencing batch reactor system is an attractive alternative. For this reason, two parallel lab-scale SBR systems were operated over an eight month period for the treatment of egg processing wastewater. The results showed very good removals of BOD, COD, and TSS. Aeration requirements were found to be 1.5 L/min for a single 4 litre reactor and 1.5 L/min & 0.5 L/min for two 4 litre reactors in series. K[sub L]a values of 5.0 hr⁻¹ and 10.8 hr⁻¹ were established for egg processing wastewater and clean water, respectively. Values for α and β were determined to be 0.46 and 0.97, respectively. The coefficients a', and b', for the determination of oxygen requirements, were established at 0.68 g O₂/g BOD and 0.36 d⁻¹, respectively. The kinetic growth coefficients were found to be: K[sub s] = 822 mg/L, k = 1.98 d⁻¹, kd = 0.07 d⁻¹, and Y = 0.32. The reductions in coliforms were from 3500 MPN/100 mis in the influent to 80 MPN/100 mis in the effluent. Confirmed coliforms were identified as Bacillus sp. and Micrococcus sp.. Salmonella and fecal coliforms were absent in both the influent and effluent wastewater.

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Chen, Chiahsin, and 陳佳欣. "Treatment of Chemical Mechanical Polishing Wastewater by Dead-end Microfiltration : Evaluation of Pretreatment Process and Their Effects." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/r7xytm.

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碩士
國立交通大學
環境工程系所
92
Chemical mechanical polishing process is a common practice for wafer planarization of the IC manufacturing. In the process, colloidal silica is used to planarize the oxide wafer surface. In the mean time, a large amount of ultrapure water is used to clean the surface of the wafer. The CMP wastewater, therefore, contains large quantity of fine particles. In Taiwan, most fabs treat the CMP wastewater with the traditional coagulation/sedimentation process, resulting in large quantity of sludge required to be disposed. A more logical solution is to reclaim the water resource from the immense amount of wastewater. This study proposed an innovative CMP wastewater treatment process with microfiltration (MF) coupled with a pretreatment of coagulation/flocculation. In the experiment, the wastewater was first filtered through a polytetrafluoroethylene (PTFE) membrane of pore size 0.5 μm at a low vacuum pressure (0.65 kg/cm2). The permeate flux and the irreversible fouling of the membrane were monitored. The SEM image of the membrane confirmed the serious fouling by the CMP wastewater. The cake layer was dense and non-porous in appearance. Different coagulants and flocculants were applied in the pre-coagulation process, and their effects on permeate flux and irreversible fouling of the membrane were determined. Results showed that polyaluminum chloride was the most efficient coagulant, which had a wider pH range for total silica removal. In addition, solid silica removal favored acidic condition while alkaline condition enhanced dissolved silica removal. Addition of trace amount of cationic polyacrylamide after the coagulation increased the size of the floc and improved the permeate flux. The addition of oxidant, namely, sodium hypochlorous, after flocculation reduced the irreversible fouling and promoted the pure water flux recovery of the membrane.

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Dissertations / Theses on the topic 'Wastewater treatment. eng'

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