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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

Acclimation of Activated Sludges to Industrial Wastes

Stephens, A. O. 05 1900 (has links)
<p> The procedures used to acclimate activated sludges for design criteria were reviewed. Experiments were performed to determine if cultures could be developed with the same characteristics as activated sludge from an actual treatment plant. Acclimation studies were performed with three refinery wastes. The resultant mixed cultures were compared, using removal rates, with activated sludge mixed cultures from the refinery's waste treatment plants. Soluble organic carbon was monitored for the removal rate curves. An acclimation procedure is proposed to be used in design studies so that a designer can place confidence limits on design data obtained from the batch reactor studies.</p> / Thesis / Master of Engineering (MEngr)
2

Ekotoxikologické hodnocení kalů z čistíren odpadních vod / Ecotoxicological evaluation of the sludges from water treatment plants

Hellingerová, Lucie January 2008 (has links)
Evaluation of the sewage sludges from different sewage water treatments will be performed by means of available ecotoxicity tests. The evaluation will be done in accordance with the valid legislation. On the basis of the obtained values the sludges will be classified into the respective grades of leachability and the dangerous property of the sewage sludges ecotoxicity will be evaluated.
3

Zhodnocení odvodnitelnosti vodárenských kalů metodou CST. / Evaluation of dewatering of waterworks sludges with CST method

Svěrák, Michal January 2014 (has links)
Main subject of the diploma thesis is an evaluation of waterworks sludge dewatering using the CST method. The CST or capillary suction time is method developed to evaluate specific resistance to filtration in an indirect way. In principle it is based on the use of filtration paper to measure willingness of sludge to release water or its filterability. Results are measured as time needed for the water to overcome a defined trajectory and expressed in seconds. The shorter the CST time the more filterable is the sludge sample. The CST method has been critically evaluated and it was assessed as a great method for selecting the ideal polymer used for the sludge dewatering and for defining its optimal dose. Measurements have been made on sludge from two waterworks plants Želivka and Kozičín. Polymer products from company Sokoflok and products Praestol and Magnafloc have been tested on both of them. The best polymers for dewatering have been selected. It was Sokoflok 104 for sludge Želivka 1, 55CN for sludge Želivka 2, Magnafloc for sludge Kozičín 1 and 55CN for sludge Kozičín 2. Second subject of the thesis was to evaluate a sludge sensibility to the shear rate. Havlík (2003) and Bache et al.(2003) are describing sludge as a substance very sensitive to higher shear rate which causes that the aggregates...
4

Estudo da metodologia do teste de atividade metanogênica específica / Study of the methanogenic activity specific test methodology

Penna, Jorge Adílio 13 April 1994 (has links)
A atividade metanogênica específica foi estudada neste trabalho a partir do levantamento de diversas metodologias propostas para a realização desse teste . Procurou-se otimizar o teste de atividade metanogênica tomando-se por base a metodologia adotada por Willem de Zeeuw (1984). No desenvolvimento do trabalho experimentou-se várias condições metodológicas para o teste de atividade, objetivando-se a máxima atividade metanogênica específica do lodo, através de um ensaio que fosse simples e rápido. Para isso, utilizando-se de cinco tipos de lodos anaeróbios, estudou-se a influência das quantidades de biomassa e de substrato, da natureza do substrato, da forma de agitação do meio, das soluções de nutrientes e de metais, da redução do meio com nitrogênio, do volume dos frascos-reatores e do tempo de armazenamento do lodo nos resultados dos testes de atividade. Observou-se que, em função do tipo de lodo e da sua atividade metanogênica, devem ser pesquisados o substrato mais adequado e a relação ótima entre a quantidade de substrato e biomassa que conduzam à atividade metanogênica específica máxima durante o teste. Observou-se também que o ensaio pode ser mais simples e mais rápido, comparativamente àquele baseado na metodologia de de Zeeuw (1984). Como conclusão principal são apresentadas novas condições metodológicas para o teste de atividade metanogênica específica para lodos anaeróbios. / The specific methanogenic activity test was studied with basis on several methodologies proposed for carrying out the referred test. The methodology used by Willem de Zeeuw (1984) was employed to optimize this test. Several methodological processes were used for the activity test in an attempt to reach the maximum specific methanogenic activity of the sludge in a simple and quick process. Five types of anaerobic sludges were used and the following parameters were studied: the influence of the amounts of biomass and substrate, the nature of substrate, the liquor mixing, the nutriente and metal solutions, oxygen removal the reactor capacity, and the sludge storage time in the results of the activity tests. It was observed that the more suitable substrate and the optimum relationship between the quantity of substrate and biomass must be researched, sludge, so that the referred according to the type of relationship leads to a maximum specific methanogenic activity. It was observed that the test can be quicker and simpler than de Zeeuw\'s (1984). The main result reached consists of the presentation of new conditions to carry out the test of specific methanogenic activity for anaerobic sludges.
5

Estudo da adição de lama de bauxita em polímero de poli(metacrilato de metila) por meio de polimerizaçao em massa e moldagem em casting / Study of red mud addition in the poli (methyl metacrylate) by mass polymerization and casting process molding

SOUZA, WANDER B. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:55:03Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:56Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
6

Estudo da adição de lama de bauxita em polímero de poli(metacrilato de metila) por meio de polimerizaçao em massa e moldagem em casting / Study of red mud addition in the poli (methyl metacrylate) by mass polymerization and casting process molding

SOUZA, WANDER B. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:55:03Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:05:56Z (GMT). No. of bitstreams: 0 / O trabalho refere-se ao desenvolvimento de formulações de poli (metacrilato de metila) (PMMA) contendo lama de bauxita proveniente de processo Bayer. A adesão entre a lama de bauxita e o poli (metacrilato de metila) ocorreu em todas as concentrações testadas (10-70%), mostrando o aumento progressivo das propriedades mecânicas de resistência à tração, resistência à flexão e módulo de elasticidade na tração como na flexão. As propriedades mecânicas são compatíveis com as diversas finalidades de emprego de superfícies sólidas. A estabilidade térmica do composto de poli (metacrilato de metila) com alto nível de lama de bauxita (70%) é semelhante a do material padrão estudado. Os estudos de citoxidade revelam que superfícies sólidas obtidas a partir de lama vermelha não possuem toxidade nas condições testadas. / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
7

Evaluation of sewage digested sludge conditioning and dewatering through qualitative and quantitative laboratory methodologies towards process monitoring

Oliveira, Ivo Miguel Delgado Bandeira January 2017 (has links)
This thesis reports on investigations that have contributed to an advancement in the applied and fundamental understanding on how the nature, related storage and processing of digested sewage sludge can influence polymer conditioning and dewatering. The work concentrated more specifically on evaluating the impact of thermal hydrolysis as a pre-treatment to anaerobic digestion (AD) of mainly secondary sewage sludges (Advanced AD, AAD plants) in comparison with conventional mesophilic AD (CMAD) on conditioning and dewatering of the digestate, as this knowledge seemed to be lacking for an AAD technology that is increasingly being implemented. An additional contribution to knowledge from this study relates to the evaluation of how polymer conditioning and dewatering of digested sludges could be monitored using rheometric measurements. It was concluded that digested sludge biofloc characteristics (size, shear viscosity and organic matter composition) affected the most the conditioning and dewatering results but these varied depending on the process conditions i.e. AAD versus CMAD and digestate handling conditions. The reduction in particle size and shear viscosity (η[0.1 s-1]) per g Total Solids as well as the increased solubilization of protein, organically bound nitrogen and chemical oxygen demand of the digestates which contributed to the increased conditioning requirements affected also the dewatering rate and the strength of the flocs produced after conditioning. The changes in the digested sludge biofloc characteristics were detected by rheometric measurements which were well correlated with changes in organic matter composition and polymer conditioning requirements (r of 0.9 and 0.8). It was proposed that the variations in η[0.1 s-1] and organic matter content such as soluble protein could be used to predict polymer dose requirements to achieve good filterability (R2 of 0.7; significance F and p < 0.05). Future work is however required in order to consolidate these findings by monitoring conditioning, dewatering and η[0.1 s-1] of the digestate at full scale.
8

An Investigation Of Agricultural Use Potential Of Wastewater Sludges In Turkey With Respect To Heavy Metals And Pathogens

Ozsoy, Gulcin 01 September 2006 (has links) (PDF)
Landfilling is the most common method that is used in the final disposal of sludge all around the world as well as in Turkey. However increasing sludge quantities and limited landfilling areas make this method invalid. Use of sludge in agriculture presents a possible alternative for disposal. However, it also poses some risks to be evaluated. In this respect, it is important to identify heavy metal and pathogen content of sewage sludges because of their adverse health effects. This study aims to determine the heavy metal contents and pathogen levels of sludges from four different wastewater treatment plants of Turkey. The selection of plants was done according to the different treatment technologies applied to wastewater and sludge in those plants. Heavy metal analysis of sludges was conducted by using microwave assisted digestion procedure and pathogen levels were done by methods from Standard Methods (SM), ISO and USA EPA. After sampling and analysis, the results show that all the related metal concentrations are below the values that are set in the Soil Pollution Control Regulation of Turkey. However in sludges from Ankara and Kayseri wastewater treatment plants, Zinc and Nickel concentrations should be tracked carefully. The results related with pathogen levels in sludges show that dewatered sewage samples taken from Ankara, Kayseri and Kemer wastewater treatment plants do not meet neither Class A nor Class B fecal coliform limits set by USA EPA however lime stabilized dewatered sludge from izmir wastewater treatment plant meet the requirement. In addition, Salmonella levels in Kayseri dewatered sludges exceed the limit value.
9

Caracterização de Lodos e Efluentes Industriais gerados por uma Empresa de Beneficiamento de Argilas visando o atendimento a PNRS

Sá, Natan Pires 29 September 2014 (has links)
Submitted by Maike Costa (maiksebas@gmail.com) on 2016-01-05T13:30:19Z No. of bitstreams: 1 arquivototal.pdf: 3020998 bytes, checksum: ef41143ea8b6c614b7a591f6da2a7baa (MD5) / Made available in DSpace on 2016-01-05T13:30:19Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 3020998 bytes, checksum: ef41143ea8b6c614b7a591f6da2a7baa (MD5) Previous issue date: 2014-09-29 / In the industrial segment the comprehension of the characteristics of solid and liquid materials used as raw materials, whether dangerous or not, is key to their sustainable management in manufacturing products, knowing that the heterogeneity of the wastes generated limit their reuse. This work adressed the characterization of sludges and effluents derived from tests in the quality control department of a beneficiation of clays industry, aiming to present treatment and disposal alternatives in accordance with the National Policy on Solid Waste (PNRS). Analyses of pH, salinity, conductivity, total dissolved solids (TDS), bulk density, moisture content and total solids (TS – fixed and volatile) were conducted. It was observed that the sludges had high load inorganic material (L1, L2, L4 and L5), being only the sludge L3 with high load volatile organic matter, due to the solvents present. From the characterization of wet sludge (“in natura”) and dried (dehydrated and calcinated) by X-ray diffraction (XRD) and IR spectroscopy, it was found that there was preservation of the typical character of clay and the presence of activating agent. According to BET analyses and point of zero charge (PZC), various sludges had low surface areas, indicating that there would be difficulty in applying them as an adsorbent for the removal of pollutants in wastewater, but they can be incorporated into cementitious materials and glasses. Moreover, sludge L3 can be indicated as a source of energy for coprocessing in cement industry. As for the effluents, tests for specific reuse of three effluents (E1, E3 and E5) were conducted, indicating preliminarily that each of them can be reused, either in the laboratory, as a fuel, or in the original process. / No âmbito industrial o entendimento das características dos materiais sólidos e líquidos usados como matérias-primas, perigosos ou não, é fundamental para a gestão sustentável dos mesmos na fabricação de produtos, sabendo-se que a heterogeneidade dos resíduos gerados limita o seu reúso. Este trabalho abordou a caracterização de lodos e efluentes provenientes de ensaios no setor de controle de qualidade de uma indústria de beneficiamento de argilas, visando propor alternativas de tratamento e disposição final conforme a Política Nacional de Resíduos Sólidos (PNRS). Foram realizadas as análises pH, salinidade, condutividade, sólidos totais dissolvidos (STD), densidade aparente, teor de umidade e sólidos totais (ST – fixos e voláteis). Observou-se que os lodos tiveram alta carga de material inorgânico (L1, L2, L4 e L5), sendo apenas o lodo L3 com alta carga de matéria orgânica volátil, devido aos solventes presentes. A partir das caracterizações dos lodos úmidos (“in natura”) e secos (desidratados e calcinados) por difração de raios-X (DRX) e espectroscopia no IV constatou-se que houve preservação do caráter típico de argilas e da presença de agente ativante. De acordo com as análises superficiais de BET, e ponto de carga zero (PCZ) vários dos lodos apresentaram baixas áreas superficiais, ou seja, indicando que haveria dificuldade de aplicação como adsorvente na remoção de poluentes em efluentes, mas eles podem ser incorporados em materiais cimentícios, vidros, e ainda, o lodo L3 pode ser indicado como fonte de energia para coprocessamento na indústria cimentícia. Quanto aos efluentes foram realizados testes de reutilização específicos para três efluentes (E1, E3 e E5), indicando-se preliminarmente que cada um pode ser reutilizado, seja em laboratório, como combustível, ou no próprio processo de origem.
10

Residuos de agrotoxicos em lodo de estacao de tratamento de agua: validacao de metodologia analitica utilizando cromatografia liquida acoplada a espectrometria de massas em TANDEM (LC-MS/MS) / Pesticides residues in water treatment plant sludge: validation of analytical methodology using liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS)

MORACCI, LUIZ F.S. 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:55:14Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:06:02Z (GMT). No. of bitstreams: 0 / Dissertação (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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