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

Techniques for the evaluation of wastewater treatment processes

De Bel, Maud January 2001 (has links)
This study focussed on extending and applying techniques to measure hydrodynamic characteristics in treatment units at sewage works. Use was made of tracer dye studies and a spreadsheet based analysis tool. The resulting infonnation about residence time, tank conguration and pathological behaviour was linked to other infonnation from respirometry and flow and load studies. Characterising the wastewater process will become increasingly important as the economic and compliance drivers in the operation of wastewater treatment facilities become increasingly pronounced. Case studies at Royton WWTW, Chorley WWTW, Preston WWTW and Montebello WWTW were used to develop, improve and apply the methodology. Tests at Royton and Chorley were used to develop the practical side of conducting tracer studies. The Preston case study was used to improve the diagnostic methodology. It was demonstrated that consent failures as a result of events are usually a result of a number of (linked) factors, in the case of Preston influenced by the tank conguration. The response of a pulse of dye was measured at Preston in vessel outlet throughout the works. The tracer dyeresponse was used to predict the response to a discharge of high ammoniacal leachate liquor and compared to measured data. This type of calibration experiment facilitated the simulation of different discharge event scenarios. The tracer and modelling techniques were incorporated in a general diagnostic methodology, which caters for a phased approach in diagnostic studies. A series of diagnostic tables take the user through cause - effect hypotheses and possible measurement techniques to use in the diagnostic investigation. Although the diagnostic methodology proved to be a versatile asset optimisation tool, which required considerable less effort than deterministic models, implementation in United Utilities' AMP3 Capital Investment Programme was problematic. The size of the programme and lack of resources forced the company to implement standard rather than tailor-made solutions. However, the diagnostic methodology can easily be applied elsewhere in the wastewater industry.
2

A field study of sewage effluent ponds

Krill, Robert Michael. January 1970 (has links)
Thesis (M.S.)--University of Wisconsin, 1970. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 126-129).
3

Flocculation modelling in wastewater treatment

Thomas, David N. January 1999 (has links)
No description available.
4

Effects of hydraulic loading and laundry detergent on the operation of aerobic package treatment systems /

Hanna, K. Michael, January 1993 (has links)
Thesis (M.S.)--Virginia Polytechnic Institute and State University, 1993. / Vita. Abstract. Includes bibliographical references (leaves 91-95). Also available via the Internet.
5

Funcionamento atual de solos submetidos ao manejo afeto à cultura da cana-de-açúcar: caracterização para fins de irrigação com efluente de esgoto tratado. Área experimental da Usina Cosan, Piracicaba- SP

Aquino, Aline de [UNESP] 17 October 2008 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:27:53Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-10-17Bitstream added on 2014-06-13T20:36:27Z : No. of bitstreams: 1 aquino_a_me_rcla.pdf: 2664343 bytes, checksum: 2664dac2efd41911b0423e12757905d3 (MD5) / Trata-se do estudo macro, micromorfológico, mineralógico, físico e químico da cobertura de solos de uma área experimental para fins de irrigação com efluente de esgoto tratado. A área localiza-se na cidade de Piracicaba, na Fazenda Taquaral, arrendada à Usina Cosan, para cultivo da cana-de-açúcar. A área cedida pela Usina, unidade Santa Helena, para o experimento foi dividida em 10 parcelas e, tanto essas, quanto o efluente, receberão um determinado tipo de tratamento. Os objetivos deste trabalho foram compreender o funcionamento atual dos solos da área experimental e verificar a possibilidade de influência e/ou modificações da cobertura de solos com a utilização do efluente. A metodologia adaptada para a pesquisa foi a Análise Estrutural da Cobertura Pedológica (BOULET, 1982 a, b). A caracterização dos solos foi feita em uma seqüência de solos e por meio de doze sondagens em cada parcela, de 0 a 100 cm de profundidade. As análises realizadas foram morfológica, física, química e mineralógica, tanto para a seqüência quanto para as sondagens. A análise micromorfológica foi realizada apenas para os solos da seqüência. As características do efluente foram cedidas pelo Departamento de Água e Esgoto de Piracicaba. As análises permitiram classificar o solo da área como Argissolo Vermelho-Amarelo Eutrófico típico, caracterizar e entender o funcionamento atual dos solos, antes da irrigação com o efluente e deduzir as possíveis mudanças do sistema solo a partir do início da irrigação. / The present work is a macro, micromorphological, mineralogical, physical and chemical study in an experimental area with the purpose of irrigation with treated sewage effluent. The area is located in the city of Piracicaba, at Taquaral Farm and leased to Cosan factory for sugar cane cultivation. The area was ceded by the factory for the experiment and divided in 10 parts, in accordance with the kind of treatment to be used with the effluent. This work had the purpose to analyze the soils of the experimental area, to understand its dynamics and to check the possibility of influence and change on the soils’ covering by the usage of effluents. The soil study was based on the methodology of the Structural Analysis of the Pedological Cover (BOULET, et al. 1982. a, b), with adapt. The soil characterization was made in a sequence of soil and through twelve investigations in each part, until 100cm depth. The analysis made were morphological, physical, chemical and mineralogical, for the sequence as well as for the investigations. The micromorphological analysis was made only in the sequence of soil. The effluent characteristics were provided by the Piracicaba Water and Sewage Department. The soil was classified into Typic Hapludults and the analyses were important to characterize and understand the soil’ dynamic before irrigation with treated sewage effluent and deduce the changes in the soil system with the effluent irrigation.
6

The impact of sewage effluent on the benthic macroinvertebrate community of the upper Thredbo River

Tiller, David, n/a January 1988 (has links)
Thredbo Village is a year round alpine resort located in Kosciusko National Park, south eastern New South Wales. Treated sewage effluent from Thredbo Village is discharged to the upper Thredbo River. The river is a rocky bottomed, high mountain stream (> 1,200 m altitude in the study area) flowing predominantly through subalpine woodland, the only major impact on the river within the study area was that of the Thredbo Village alpine ski resort. Nutrient concentrations were measured in the upper Thredbo River monthly from January to September 1983 at 9 sites along the river, both upstream and downstream of the effluent discharge. In addition, invertebrates were collected at the same sites in January, April and July 1983. The near pristine section of the upper Thredbo River upstream of Thredbo Village was low in phosphorus and nitrogen (<20 mg m-3 and <100 mg m-3 respectively). The sewage effluent discharge was high in phosphorus and nitrogen (up to 5,000 mg m-3 and 28,000 mg m-3 respectively). Phosphorus generally returned to concentrations similar to those measured in the pristine sections by 3.5 kilometres downstream of the discharge. Nitrogen (mostly in the form of nitrate and nitrite) often remained elevated down to the most downstream site, 8 kilometres downstream of the effluent discharge. The elevated nutrient concentrations immediately downstream of the effluent discharge stimulated the growth of attached filamentous algae in January when conditions for growth were most favourable. It is concluded that this growth provided an additional food source for several invertebrate taxa, Cricolopus sp. 12E and 160E (Diptera, Chironomidae), Conoesucidae sp. TR6, Oxyethira columba (Trichoptera), Nais sp., Aeolosomatus niveum (Oligochaeta), and Austrocercella tillyardi (Plecoptera), which occurred in higher numbers downstream of the effluent discharge. Downstream of the effluent discharge the taxonomic composition of the invertebrate community was not altered substantially from that upstream, although there was a significant increase in the abundance of the taxa which could take advantage of the increased food resource. The changes in the invertebrate community were not evident 3.5 kilometres downstream of the effluent discharge, which corresponded to the return of phosphorus concentrations to background levels. There were increased abundances of several invertebrate taxa downstream of both Thredbo Village and the rubbish tip in January which were consistent with, but not as great as, those downstream of the sewage effluent discharge. This was likely to be a result of increased nutrient loads from urban runoff and tip leachate at these sites which possibly lead to increased algal productivity. However, nutrient concentrations at these sites were not notably higher than at the control site. The sewage effluent discharge resulted in only small changes to the invertebrate community in April or July 1983.
7

Water quality improvement and plant root function in an ecological system treating dairy wastewater

Morgan, Jennifer Anne, January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 115-119).
8

Funcionamento atual de solos submetidos ao manejo afeto à cultura da cana-de-açúcar : caracterização para fins de irrigação com efluente de esgoto tratado. Área experimental da Usina Cosan, Piracicaba- SP /

Aquino, Aline de. January 2008 (has links)
Orientador: Nádia Regina do Nascimento / Banca: Célia Regina Montes / Banca: Sônia Maria Furian Dias / Resumo: Trata-se do estudo macro, micromorfológico, mineralógico, físico e químico da cobertura de solos de uma área experimental para fins de irrigação com efluente de esgoto tratado. A área localiza-se na cidade de Piracicaba, na Fazenda Taquaral, arrendada à Usina Cosan, para cultivo da cana-de-açúcar. A área cedida pela Usina, unidade Santa Helena, para o experimento foi dividida em 10 parcelas e, tanto essas, quanto o efluente, receberão um determinado tipo de tratamento. Os objetivos deste trabalho foram compreender o funcionamento atual dos solos da área experimental e verificar a possibilidade de influência e/ou modificações da cobertura de solos com a utilização do efluente. A metodologia adaptada para a pesquisa foi a Análise Estrutural da Cobertura Pedológica (BOULET, 1982 a, b). A caracterização dos solos foi feita em uma seqüência de solos e por meio de doze sondagens em cada parcela, de 0 a 100 cm de profundidade. As análises realizadas foram morfológica, física, química e mineralógica, tanto para a seqüência quanto para as sondagens. A análise micromorfológica foi realizada apenas para os solos da seqüência. As características do efluente foram cedidas pelo Departamento de Água e Esgoto de Piracicaba. As análises permitiram classificar o solo da área como Argissolo Vermelho-Amarelo Eutrófico típico, caracterizar e entender o funcionamento atual dos solos, antes da irrigação com o efluente e deduzir as possíveis mudanças do sistema solo a partir do início da irrigação. / Abstract: The present work is a macro, micromorphological, mineralogical, physical and chemical study in an experimental area with the purpose of irrigation with treated sewage effluent. The area is located in the city of Piracicaba, at Taquaral Farm and leased to Cosan factory for sugar cane cultivation. The area was ceded by the factory for the experiment and divided in 10 parts, in accordance with the kind of treatment to be used with the effluent. This work had the purpose to analyze the soils of the experimental area, to understand its dynamics and to check the possibility of influence and change on the soils' covering by the usage of effluents. The soil study was based on the methodology of the Structural Analysis of the Pedological Cover (BOULET, et al. 1982. a, b), with adapt. The soil characterization was made in a sequence of soil and through twelve investigations in each part, until 100cm depth. The analysis made were morphological, physical, chemical and mineralogical, for the sequence as well as for the investigations. The micromorphological analysis was made only in the sequence of soil. The effluent characteristics were provided by the Piracicaba Water and Sewage Department. The soil was classified into Typic Hapludults and the analyses were important to characterize and understand the soil' dynamic before irrigation with treated sewage effluent and deduce the changes in the soil system with the effluent irrigation. / Mestre
9

Estudos espectroscópicos de matéria orgânica e ácidos húmicos de solos sob adição de efluente de esgoto tratado / Spectroscopic studies of organic matter and humic acids from soil with addition of treated sewage effluent

Martins, Bruno Henrique 03 August 2009 (has links)
A crescente demanda de água nas cidades tem feito o homem buscar diferentes fontes de irrigação de culturas na agricultura, em se tratando de uma atividade que requer um grande montante de água. Neste contexto, o uso de efluente de esgoto tratado (EET), industrial ou doméstico, substituindo a água utilizada na irrigação de várias culturas, tem se mostrado ser uma medida promissora para preservá-la para o consumo humano.O propósito deste trabalho foi avaliar através de técnicas espectroscópicas (Infravermelho com Transformada de Fourier - FTIR, Espectroscopia de Fluorescência, Espectroscopia de Absorção de UV-Visível, Ressonância Paramagnética Eletrônica - RPE), as mudanças na matéria orgânica do solo (MOS) e ácidos húmicos (AH) extraídos de solo irrigado ou não com efluente de esgoto tratado, nas seguintes condições de irrigação: SI (sem irrigação com EET), 100 (irrigação com EET e umidade de solo na capacidade de campo) e 200 (irrigação com EET e umidade de solo 100% acima da capacidade de solo). Além dessas técnicas foi determinada a porcentagem de carbono e utilizada a espectroscopia de Fluorescência Induzida por Laser (FIL) para medir o grau de humificação de amostras de solo intacto, irrigados ou não com EET. As amostras de solo, sob cultura de cana-de-açúcar, foram coletadas em campo experimental situado em Lins-SP, em diferentes profundidades até 100 cm. As análises das amostras de solo demonstraram um decréscimo de porcentagem de carbono na faixa de 2 a 15% para as condições de irrigação com EET. O resultado é preocupante considerando tratar-se de solos com menos de 1% de conteúdo de carbono, e que tem com a aplicação do EET uma diminuição adicional na MOS, o que pode ser altamente limitante para a fertilidade e estrutura do solo. Os resultados obtidos por FIL para as mesmas amostras mostraram um aumento no grau de humificação variando de 9 a 30% nas áreas irrigadas com EET em relação às áreas não irrigadas com EET. Esse aumento do grau de humificação MOS é consistente com a diminuição de carbono do solo que mais provavelmente perde frações mais lábeis, permanecendo as mais recalcitrantes. Os espectros obtidos pela espectroscopia de FTIR para os AH analisados foram típicos, não mostrando diferença significativa, considerando as diferentes camadas de profundidade e irrigação ou não com EET. Os resultados obtidos por espectroscopia de fluorescência, usando três diferentes metodologias, de AH em solução mostraram, assim como a espectroscopia de FIL para amostras de solo, aumento no grau de humificação conforme aplicação de EET Assim como no caso da MOS, tal aumento no grau de humificação pode ser atribuído à degradação de frações de carbono mais lábeis e permanência das mais recalcitrantes dos ácidos húmicos analisados. Os resultados de razão E4/E6 (razão entre as intensidades de absorbância em 465 e 665 nm) para os AH analisados obtidos através da espectroscopia de absorção de UV-Visível denotaram decréscimo em seus valores nas camadas superficiais, comparando-se as três condições analisadas. Os resultados obtidos pela espectroscopia de RPE mostraram um aumento na concentração de RLS (radicais livres semiquinona) nos AH nas duas condições de irrigação, 100 e 200, sendo mais pronunciado na segunda. Corroborando com os resultados obtidos através das demais espectroscopias utilizadas, tal aumento da concentração de RLS provavelmente é oriundo de aumento de grau de humificação. Dessa forma, de acordo com os dados obtidos, o emprego de ET como fonte de irrigação em substituição à água, nas condições de solo analisadas são preocupantes, pois pode trazer limitações para a fertilidade e estrutura do solo, conforme evidenciado pelo decréscimo no conteúdo de MOS.Contudo, os experimentos devem ser continuados para confirmar e validar as tendências iniciais detectadas, bem como para buscar as alternativas de manejo dos solos e culturas para viabilizar a aplicação do EET em condições que sejam sustentáveis. / The increasing demand of water sources in the cities has done the man search for other different sources for irrigation of cultures in agricultural fields, hence it\'s an activity that demands a large amount of water. In this context, the use of treated sewage effluent (TSE), industrial or domestic, instead of water for irrigation of several cultures, has been shown to be a very promising way to save water for human consume.The purpose of this study is to evaluate by spectroscopic techniques (Fourier Transformed Infra-Red - FTIR, Fluorescence Spectroscopy, UV-Visible Spectroscopy and Electron Paramagnetic Resonance - EPR) the changes in the soil organic matter (SOM) and humic acids (HA) extracted from soils irrigated or not with treated sewage effluent, in the following concentrations of irrigation: SI (soil non-irrigated with TSE), 100 (soil irrigated with TSE and soil humidity in the same level of field capacity) and 200 (soil irrigated with TSE and soil humidity 100 % above field capacity). Besides these techniques, it was also determined the carbon percentage and used the Laser-Induced Fluorescence (LIF) spectroscopy to measure the degree of humification in samples of whole soil, irrigated or not with TSE. The soil samples analyzed in this study were collected from an experimental field in the city of Lins - SP, from a sugarcane culture soil, in the depth till 100 cm. The analysis of samples of whole soil showed a decrease in the carbon percentage in the range of 2 to 15% in the irrigation conditions comparing with the non - irrigated area. These results are preoccupying considering that it\'s a soil with less of 1% of carbon content, and has an additional decrease in the SOM when irrigated with TSE, what may cause limiting in the soil fertility and structure. The results obtained by LIF for the same samples, showed an increase in the humification degree varying from 9 to 30% in the irrigated area. This increase in the humification degree of soil organic matter (SOM) is consistent with carbon percentage decreasing in soil, which probably loses more labile fractions, remaining the most recalcitrant ones. The spectra obtained by the FTIR spectroscopy for HA analyzed were typical, not showing a significative difference, considering different layers of depth and treatment or not with TSE. The data obtained by fluorescence spectroscopy, using three different methodologies, of HA in solution showed, as well as the LIF spectroscopy for whole soils, an increment in the humification degree according to application of TSE. At the same way that happens with SOM, this increase in the humification degree may be attributed to degradation of carbon more labile fractions and remaining of the most recalcitrant ones in the humic acids. The results of E4/E6 ratio (ratio between the absorbance intensities at 465 and 665 nm) obtained by UV-Visible spectroscopy showed a decrease in the superficial layers, comparing the three conditions analyzed. The results obtained by the EPR spectroscopy showed an increase in the concentration of SFR (semiquinone free-radicals) in the HA with the increase of depth in the two conditions of irrigation, 100 and 200, being more pronunciated in the second treatment. Corroborating with the results obtained by the others spectroscopies, this increase in the SFR concentration probably may be attributed to the increase in the humification degree. In this manner, according with the obtained data, the use of TSE as source of irrigation replacing the water in the soil condition analyzed are preoccupying, hence it may cause limitations in soil fertility and structure, as evidenced by the decrease of the SOM content. However, the experiments must continue to confirm and validate the initials tendencies detected, and to search new alternatives for soil and culture tillage to make possible the TSE application in sustainable conditions.
10

The impact of sewage effluent on the relationship between periphyton and benthic macroinvertebrates of the Thredbo River and the effects of nutrient removal

Thurtell, Lisa, n/a January 1992 (has links)
Nutrients, periphyton and macroinvertebrates were sampled every two months for one year to assess the effects of treated sewage effluent on the Thredbo River and to compare changes in chemical concentrations and the invertebrate community since the introduction of nutrient removal on the Thredbo sewage treatment plant. Chemically, the impact of the effluent was minor and was reduced from levels measured before the addition of nutrient removal to the Thredbo sewage treatment plant. However, the reduction may be the result of higher flows during the study period. Biologically there was no indication of nutrient enrichment during June, August and October, with differences occurring between physically dissimilar sites irrespective of position relative to the sewage effluent inflow. Large increases in periphyton and macroinvertebrates occurred in December, February and April at both open sites and those downstream of the sewage outflow. Previous studies found increases in invertebrate abundance and richness immediately downstream of the sewage inflow, but the impact was greater and extended further downstream than found in this study. Strong correlations between total phosphorus and periphyton biomass and chlorophyll-a indicate phosphorus was a limiting nutrient. Higher periphyton biomass and chlorophyll-a at all sites during the warmer months (especially at open sites with an even cobble substratum), throughout the year, indicates light, temperature and substratum type were as important as phosphorus in controlling algal growth. Low algal biomass during the high flow month of October also indicates the importance of water velocity in controlling periphyton biomass. The structure of the macroinvertebrate community was noticeably different at sites downstream of the effluent discharge, with the exception of the most downstream site, when compared to the upstream sites. The occurrence of high macroinvertebrate numbers and species richness at sites with high periphyton growth and the strong positive correlation between invertebrate grazers and periphyton measurements shows a dependent relationship between invertebrates and periphyton growth. Therefore, the physical factors of light, temperature and substratum characteristics of particular sites in the Thredbo River, may be as important in controlling the benthic community as the levels of nutrient inputs from sewage.

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