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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

Výzkum regenerace filtračního materiálu zemních filtrů a kořenových čistíren odpadních vod / The Research on Regeneration of the Filter Material, used in the Soil Filters and Constructed Wetlands

Burešová, Hana January 2012 (has links)
The thesis consists of two basic parts. The first research part creates an introduction to the root zone wastewater treatment plants. It contains mainly causes of filter environment colmation and its theoretical solution methods, which are further solved in the laboratory. The master’s thesis attempts to find a simple way, which would in future be possible to evaluate the rate of sedimentation of the sludge material, which causes filtration environment colmation. Results of developed methodology will be used in practice by washing colmated filtration material, respectively colmatant separation in sedimentation tank. The thesis focuses to verify the possibility flocculation and mineralization of sludge, which adheres to the surface of the filtration material. The solution lies in the observation of sedimentation rate (after previous dilution) using by the turbidimetric method, based on the beam-column passage through muddy water. The results show that it is not critical ambient temperature, but the time effect of natural mineralization in combination with moisture (dry matter concentration, the amount of water). The present thesis evaluates the possibilities and application method, leading to the natural regeneration of the filtration material exposed to natural climatic conditions.
2

AVALIAÇÃO DO POTENCIAL DE USO DE RESÍDUOS DE CAFÉ COMO FILTROS PARA TRATAMENTO DE ÁGUA RESIDUÁRIA DA CAFEICULTURA / Evaluation of the potential for using coffee husk as filters for coffee wastewater treatment.

José Lanzilot Elias de Lima 14 December 2006 (has links)
lt;p align="justify"gt; O presente trabalho teve como objetivo avaliar o potencial de uso de resíduos de café como filtros orgânicos para tratamento de água residuária da cafeicultura (ARC). Para isso foram testados resíduos gerados na própria lavoura, o pergaminho do grão do café e pergaminho + casca do fruto do cafeeiro como materiais filtrantes de água de lavagem e despolpa dos frutos. Para a montagem dos filtros levou-se em consideração a granulometria dos materiais filtrantes uma vez que interfere, diretamente, em sua porosidade, e esta na eficiência de filtração da ARC. Foram avaliados parâmetros da qualidade da ARC em relação às características físicas (condutividade elétrica – CE e sólidos totais - ST e em suspensão - SS) e químicas (pH, N, Ca, Mg, Na, K, Fe, Zn, Cu, Mn e P) da água antes e após a filtração e se o efluente (filtrado) atende aos padrões do CONAMA para lançamento nos corpos d’água. Com base nos resultados, pôde-se concluir que todos os valores das concentrações relativas de sólidos nos efluentes dos filtros permaneceram aquém do valor de 50 mg L-1 como concentração admitida para um bom funcionamento do sistema de irrigação por gotejamento. O filtro orgânico de pergaminho e de pergaminho + casca do fruto do cafeeiro apresentaram uma remoção razoavelmente alta de sólidos da ARC, tendo sido obtidos eficiências máximas de remoção de SS de 80% para filtros de pergaminho (operando por 120 min, material da peneira malha nº 4) e de 85% para filtros de pergaminho + casca do fruto do cafeeiro (operando 90 min, material da peneira malha n0 6), e obtidos eficiências máximas de remoção de ST de 89% para filtros de pergaminho (operando por 120 min, material da peneira malha n0 6) e de 95% para filtros de pergaminho + casca do fruto do cafeeiro (operando 90 min, material da peneira malhas n0 4 e n0 6). Apesar disso, esses filtros não foram eficientes para atender a legislação do CONAMA que, estabelece os parâmetros para lançamento de efluentes em corpos hídricos. Mesmo não atendendo a legislação do CONAMA, indubitavelmente o uso de filtro orgânico permitiu melhoria considerável na qualidade do efluente, o que facilita enormemente as etapas subseqüentes do tratamento da ARC.lt;/pgt; / lt;p align="justify"gt; The objective of the present work was to evaluate the use of organic filters for coffee processing wastewater treatment (CPW). Residues produced in the farm, coffee parchment and coffee parchment + outer skin, were tested as filter material for water from coffee wet processing. To develop the filters, the granulometry of the filter material was taken into consideration, since it directly affects the porosity and consequently the efficiency of CPW filtration. Quality parameters of CPW physical characteristics (electrical conductivity – EC, total solids – TS and solids in suspension - SS) and chemical characteristics (pH, N, Ca, Mg, Na, K, Fe, Zn, Cu, Mn and P) were evaluated before and after filtration, and whether the effluent (filtrate) complies with the National Environmental Council (CONAMA) standards for releasing into bodies of water. The results showed that all the values for relative solids concentrations in the filter effluents were below 50 mg L-1, which is the accepted concentration for the successful operation of drip irrigation systems. The organic filter using parchment and parchment + outer skin of coffee beans gave a reasonably high CPW solids removal, with maximum SS removal efficiencies of 80% for parchment filters (operating for 120 min, 4-mesh sieve) and 85% for parchment + outer skin filters (operating for 90 min, 6-mesh sieve), and maximum TS removal efficiencies of 89% for parchment filters (operating for 120 min, 6-mesh sieve) and 95% for parchment + outer skin filters (operating for 90 min, 4 and 6 mesh sieve). However, these filters were not efficient to comply with the CONAMA legislation that establishes the parameters for effluent release into bodies of water. Even not complying with the CONAMA legislation, undoubtedly the use of organic filters allowed considerable improvement in effluent quality, greatly facilitating the following stages of CPW treatment.lt;/pgt;
3

Phosphorus Removal from Domestic Wastewater Using Dual Reactive Materials Polonite® and Absol®.

Fatehi Pouladi, Soheil January 2011 (has links)
Private wastewater treatment facilities release tons of phosphorus to the aquatic environment due to the insufficient removal efficiency in conventional soil infiltration systems. Reactive filter materials have demonstrated promising P removal rates. Laboratory-scale column experiments were carried out using Absol® and Polonite® in dual infiltration media and results were compared with Polonite® functioning as the only layer of reactive filter material. Two sets of experiments were arranged with layer lengths of 5 cm and 15 cm which were operated for 50 and 119 days respectively. Columns with an additional layer of Absol® demonstrated very good average removal rates of 85.99 % and 99.13 % in both experiments while the effluent in the former exceeded the maximum allowed P concentration shortly after half of the total time of the experiment. On the other hand, O-P concentration in collected samples from dual filter media with 15 cm layers of Absol® and Polonite® (column B1) was as low as 0.04 mg/l after 119 days of operation exhibiting high potentials for Absol® in local wastewater treatment. Levels of pH in treated samples showed a decreasing trend in all columns which was similarly simultaneous with high removal rates observed in B1.
4

Stormwater bioretention: Pollutant occurrence and accumulation in filter materials and forebays

Furén, Robert January 2022 (has links)
Urban areas are affected by anthropogenic activities and produce pollutants that are transported to recipients and receiving waters during precipitation. Untreated stormwater runoff is a main driver of environmental degradation, and the interest in stormwater quality treatment has increased with the awareness of stormwater pollution. Several pollutants, including metals PAHs, PCBs, phthalates, and phenols, pose a hazard to aquatic life and are listed among the 45 priority substances in The European Water Framework Directive list (Directive 2013/39/EU). Stormwater bioretention technology is employed to efficiently remove pollutants during stormwater treatment in urban areas. However, the resulting accumulation of pollutants in bioretention facilities could ultimately create a pollutant depot. Hence, it is important to understand the occurrence, availability, and mobility of pollutants in bioretention facilities, as well as the processes that control their accumulation and mobility over time. The aim of the work in this licentiate thesis was to investigate the occurrence, accumulation, distribution, and concentration of organic micropollutants and metals inbioretention facilities after long-term stormwater treatment in urban areas of Ohio, Michigan, and Kentucky in November 2019. Samples were collected from 29 bioretention facilities, 20 of which were equipped with forebays. A total of 269 samples were analysed for metals commonly found in stormwater (Cr, Cu, Ni, Pb, and Zn), and a five-step sequential extraction method was used to assess the metal mobility in the filter material. Additionally, 116 samples from 12 sites were analysed for 38 organic micropollutants (OMPs), including 16 PAHs, 7 PCBs, 13 phthalates, and 2 alkylphenols. All studied metals were found in all samples, except for Cd, which was detected in 245 samples (91%). For the OMPs, 32 of 38 analytes were detected in at least one sample. PAHs and PCBs were the most frequently detected pollutants, and were found in 12 and 10 sites, respectively. The bioretention sites showed large variations in the concentrations of pollutants. The concentration of OMPs was highest in the upper 10 cm of the filter material and decreased with increasing depth, while a similar, but less obvious trend was observed for Cr, Cu, Pb, and Zn. A trend of decreasing concentration with increasing distance from the inlet was observed for OMPs but was less clear for the metals. Thefore bays, which contain sediment but no filter material, had the highest concentrations of OMPs. A strong correlation was observed between the pollutant concentrations and the ratio between the filter area and catchment area in a Principle Component Analysis. The accumulation and pathways of particle-bound OMPs and particle-bound metals showed similarities. These results will assist with improving the methods used for stormwater management. Importantly, regular replacement of the top filter layer and regular forebay maintenance may prevent pollutant accumulation and clogging, thereby extending the filters’ treatment function.
5

Odstraňování vybraných kovů z vody / Removal of selected metals from the water

Pěkný, Mojmír January 2013 (has links)
In my thesis I focused on the problem of removal of some heavy metals from water. Heavy metals cause deterioration of quality of water sources and bring about a need of complicated water treatment technologies. In particular it is the case of mercury, arsenic, cadmium, lead, chromium and nickel. This diploma thesis focuses on the utilization of adsorption using suitable adsorption materials to reduce concentrations of nickel in drinking water. At the same time it investigates the effectiveness of these materials in the process of removing iron and manganese from water. The first part of my thesis presents an overview of these metals. I write about their occurrence, its forms, properties and significance. The second part of the work focuses on the laboratory observations of the effectiveness in removing iron, manganese and nickel from water. The description of the used sorptive materials is also included.
6

Posouzení účinnosti filtračního materiálu DMI-65 na odstraňování kovů z vody / Assessment of the effectiveness of filter material DMI-65 on removing metals from water

Konečný, Jiří January 2016 (has links)
The first chapter of diploma thesis discusses about various water processes which remove metals and metalloids compounds from water. A substantial part is devoted to filter materials, which include a new filter material DMI-65. Comprehensive chapter discribes characteristics, proporties and practical application of filter material DMI-65. The next chapter describes the process of pilot testing of material DMI-65 in the water treatment plant in Ivancice. At the end of the diploma thesis, the laboratory test of filter material DMI-65 is described, including the description of particular metals that are removed from the water and the compresion of the filter materiál DMI-65 with other selected filter materials.
7

ANÁLISE DA EFICIÊNCIA DE REMOÇÃO DE FERRO E MANGANÊS DE ÁGUAS DE ABASTECIMENTO POR FILTRAÇÃO ADSORTIVA

Paz, Elaine Carvalho da 25 May 2016 (has links)
Made available in DSpace on 2017-07-20T13:41:58Z (GMT). No. of bitstreams: 1 Elaine Carvalho da Paz.pdf: 5913998 bytes, checksum: 3abfb310351a148f2f4495951bcca8d2 (MD5) Previous issue date: 2016-05-25 / The present study evaluates the iron removal efficiency (Fe), manganese (Mn), apparent color and turbidity, using adsorptive filtration compared with conventional filtration, using a natural Zeolite as layer second material in a pilot unit with constructive and operational typology similar to the rapid downward filter, gravity and double layer. As adsorbent material was selected Zeolite WATERCELL-ZF-0410®, commercially available Clinoptilotite from Cuba, for having physical characteristics similar to the anthracite coal. Morphological characterization assays were performed (FEG-SEM) and elemental (EDS), physical characteristics (particle size, density, effective size and uniformity coefficient), lixiviation and filtration on a pilot scale. Morphological characterization analysis, it was found that the zeolite under consideration has a high adsorption capacity, prone to adsorption iron, manganese and sulfur in the upper range anthracite coal. The physical characterization analysis, it was verified that this Zeolite is a uniform material and graduated, has physical similarity to the coal and anthracite can be used as filtering material of the layer second. Leaching analysis showed that, possibly, there will be no release above the maximum value allowed in CONAMA Resolution n. ° 357/2005, metals detected in the leached extract for a backwashing of filter using this material as media filter, as well as probably not occur detachment of these metals in the final disposal of this waste system. The filtration analysis on a pilot scale concluded that designing a filter with downward filtration, with depth action and double layer using the Zeolite WATERCEL-ZF-0410 on the layer second, is viable. The conception of treatment proposed, in the conditions, parameters and settings studied, has average efficiency: 100.00% for the removal of manganese; 96.17% for the removal of iron; 99.90% for the removal of apparent color; and 98.96% for the removal of turbidity. / O presente trabalho avalia a eficiência de remoção de ferro (Fe), manganês (Mn), cor aparente e turbidez, utilizando a filtração adsortiva em relação à filtração convencional, com utilização uma Zeólita natural como material de segunda camada, em uma unidade piloto com tipologia construtiva e operacional semelhante de um filtro rápido descendente e a gravidade. Como material adsorvente foi selecionado a Zeólita WATERCELL-ZF-0410, comercialmente disponível, clinoptilotita proveniente de Cuba, por possuir características físicas semelhantes à do carvão antracito. Foram realizados ensaios de caracterização morfológica (MEV-FEG) e elementar (EDS), de caracterização física (granulometria, massa específica, tamanho efetivo e coeficiente de desuniformidade), de lixiviação e de filtração em escala piloto. Da análise de caracterização morfológica, verificou-se que a Zeólita em estudo tem alta capacidade de adsorção, com predisposição para adsorção de ferro, manganês e enxofre, em escala superior ao carvão antracito. Da análise de caracterização física, verificou-se que a Zeólita em estudo é um material uniforme, bem graduado, possui equivalência física com o carvão antracito e pode ser utilizada como material filtrante de segunda camada. Da análise de lixiviação, verificou-se que, possivelmente, não haverá desprendimento, acima do valor máximo permitido na Resolução Conama n.° 357/2005, dos metais detectados no extrato lixiviado para a água de lavagem de um filtro que utilize esse material como meio filtrante, bem como, possivelmente, não ocorrerá desprendimento destes metais no sistema de disposição final deste resíduo. Da análise da filtração em escala piloto, concluiu-se que é viável a concepção de um projeto de filtro a gravidade, com filtração descendente, ação de profundidade e dupla camada, utilizando a Zeólita WATERCEL-ZF-0410 como material de segunda camada e que, esta concepção de tratamento, nas condições, parâmetros e configurações estudadas, apresentou eficiência média de: 100,00% para remoção de manganês; 96,17% para remoção de ferro; 99,90% para remoção de cor aparente; e 98,96% para remoção de turbidez.
8

Odstraňování olova i jiných kovů z vody / Removal of lead and other metals from water

Šopíková, Lucie January 2015 (has links)
This work covers the topic of metals and semimetals in water. It is divided into three parts. First, each element is characterized by its properties and behavior in water. Incidence in the environment, utilization and effects of intake on human body are described for each element. Second, means of elimination from water are introduced. Different chemical, mechanical and biological methods are discussed. In greater detail, precipitate method, cementation, electrochemical processes, sorption and biosorption are reviewed. Third, hands-on filtration experiment of polluted water with the help of different filtration materials is included. This experiment was done in a laboratory belonging to the Institute of Municipal Water Management, Faculty of Civil Engineering, Brno University of Technology.
9

A Preliminary Study On Construction Of A High Capacity Tensiometer And Its Use In Measurement Of Matric Suction In Unsaturated Soils

Koksalan, Ali Okan 01 February 2013 (has links) (PDF)
Soil suction is one of the main state parameters that governs unsaturated soil behaviour. Tensiometers are the only type of probe that can measure soil suction directly, but only up to 90 kPa. In the past two decades, a new type of tensiometer with much greater measurement range (up to 2 MPa) has appeared in the literature. The measurement range (i.e. capacity) of a tensiometer is limited by (i) how well it is saturated, and (ii) the air entry value of its porous interface. In this study, the first high capacity tensiometer of Turkey was designed and built. For the purpose of increasing the measurement capacity of the tensiometers, a novel saturation setup that uses a hydraulic pressurization system with capacity of 10 MPa was designed and built. A vacuum-and-pressure saturation procedure was developed. To calibrate the 10 MPa pressure transducers that form the core of the tensiometers, a high-pressure calibration setup capable of pressurizing up to 11 MPa was designed and built. By varying designs of tensiometer bodies, porous interfaces and seals, ways of increasing the suction capacity are investigated. Over a dozen tensiometer design variations are developed, and tried by exposing to atmospheric evaporation. A maximum suction measurement of 870 kPa was achieved with a conventional design / however, none of the new designs were successful. 3 successful designs were also briefly tried on soil samples
10

Treatment of Metals in Highway Runoff Water : Comparison of green infrastructures and filter material for stormwater treatment / Rening av metaller i dagvatten från motorvägar : Jämförelse av grön infrastruktur och filtermaterial för dagvattenrening

von Matérn, Fanny January 2023 (has links)
Highway runoff transport high concentrations of heavy metals. As climate change affect the environment with for example increased storm events, the treatment of road runoff becomes more important. This study aims to evaluate the treatment of highway runoff with constructed wetlands, stormwater ponds, vegetated filterstrips, vegetated swales and filter materials for highways in proximity to nature reserves. The treatment efficiency of constructed wetlands, stormwater ponds, vegetated filterstrips and vegetated swales was examined through a literature study and modelling of the different treatment methods using the StormTac modelling tool. Modelling was done both based on the design of a facility from the literature study and also adapted to a study area along the Södertörn Crosslink. The treatment efficiency of a sand filter as well as four reactive filter materials was determined from field studies on a pilot plant in Gröndal. The results from the study show that the guidelines for stormwater quality from Järfälla municipality can be reached with the treatment of stormwater using filter material. The treatment of heavy metals with constructed wetlands and stormwater ponds is below the guidelines for stormwater quality from Järfälla municipality for some of the studied heavy metals. However, the results from the modelling show a higher treatment efficiency than from the literature study for the majority of the studied metals. Moreover, construed wetlands and stormwater ponds also provide areas for recreation and promotion of biodiversity, which in a nature reserve area should be considered beneficial. A common issue for stormwater treatment with constructed wetlands, stormwater ponds and filter materials are that the required area for filter materials with pre-sedimentation basin, as well as the requested area for constructed wetlands and stormwater ponds, are bigger than the designated area for treatment in the case study. / Dagvatten från motorvägar för med sig höga halter tungmetaller. Effekterna av klimatförändringar påverkar miljön med till exempel fler och häftigare regn, vilket leder till att rening av vägdagvatten blir allt viktigare. Denna studie syftar till att utvärdera rening av dagvatten från motorvägar med konstruerade våtmarker, dagvattendammar, översilningsytor, svackdiken och filtermaterial för motorvägar i nära anslutning till naturreservat. Reningseffektiviteten för konstruerade våtmarker, dagvattendammar, översilningsytor och svackdiken undersöktes genom en litteraturstudie och modellering av de olika reningsmetoderna i modelleringsverktyget StormTac. Modellering gjordes både utifrån utformning av en anläggning från litteraturstudien, men även för en anläggning anpassad till ett studieområde längs Tvärförbindelse Södertörn. Reningseffektiviteten för ett sandfilter samt fyra reaktiva filtermaterial bestämdes från fältstudier på en pilotanläggning i Gröndal. Resultaten från studien visar att riktlinjerna för dagvattenkvalitet från Järfälla kommun kan nås med rening av dagvatten med filtermaterial. Reningen av tungmetaller med anlagda våtmarker och dagvattendammar ligger under riktlinjerna för dagvattenkvalitet från Järfälla kommun för några av de studerade tungmetallerna, dock visar resultaten från modelleringen en högre reningseffektivitet än från litteraturstudien för majoriteten av de studerade tungmetallerna. Konstruerade våtmarker och dagvattendammar skapar även områden för rekreation och främjande av biologisk mångfald, vilket i ett naturreservatsområde bör anses vara fördelaktigt. Ett gemensamt problem för dagvattenrening med anlagda våtmarker, dagvattendammar och filtermaterial är att det området som krävs för filtermaterial med försedimenteringsbassäng, samt det önskvärda området för anlagda våtmarker och dagvattendammar är större än det avsedda området för rening i fallstudien.

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