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Untersuchungen zur Steuerung der Mangankonzentration bei der Uferfiltration und Unterirdischen Enteisenung / EntmanganungPaufler, Sebastian 20 May 2019 (has links)
Die Uferfiltration und die unterirdische Enteisenung / Entmanganung (UEE) sind bewährte Verfahren für die natürliche, unterirdische Voraufbereitung von Wasser. In Abhängigkeit von der Wasserbeschaffenheit und den geochemischen Eigenschaften des Grundwasserleiters können Redoxreaktionen, Sorptions- und Auflösungsprozesse oder eine ungünstige Bewirtschaftung der Brunnen bei beiden Verfahren zu erhöhten Mangankonzentrationen im Rohwasser führen. Erhöhte Mangankonzentrationen sind häufig für Verockerungsprozesse im Filterbereich der Brunnen und Ablagerungen in Pumpen und Steigleitungen verantwortlich. Diese beeinträchtigen den langfristigen Brunnenbetrieb und führen zu höheren Kosten der Wasseraufbereitung. Außerdem führt Mangan zur Färbung des Wassers und muss in der Trinkwasseraufbereitung auf < 0,05 mg/L verringert werden. Für Wasserwerksbetreiber ist die Kenntnis über die Ursache und das Verhalten von Mangan essentiell für einen optimalen Betrieb.
Die ägyptische Hauptstadt Kairo steht einem stark wachsenden Wasserbedarf gegenüber. Für die Bewertung einer möglichen Anwendung der Uferfiltration am Nil wurden vorhandene Versuchsbrunnen teufenabhängig beprobt und das Flusssohlsediment untersucht. Das Flusssohlsediment wies hohe Eisen- und Mangangehalte auf und wurde als Ursache für erhöhte Eisen-, Mangan- und Ammoniumkonzentrationen im Uferfiltrat identifiziert.
Für den Uferfiltrationsstandort Dresden-Tolkewitz wurde der Einfluss von Temperatur und Infiltrationsrate auf die Manganfreisetzung aus der Elbsohle untersucht. Betriebsdaten der Jahre 2006 bis 2016 und Säulenversuche bildeten die Grundlage. Die Manganfreisetzung wurde primär von der Temperatur kontrolliert, die Infiltrationsrate war weniger wichtig und verlor mit steigender Temperatur weiter an Bedeutung. Eine Manganfreisetzung wurde bei Wassertemperaturen von 20 °C und Infiltrationsraten von ≥ 0,3 m³/(m²×d) ausgelöst.
Während der Inbetriebnahme eines UEE-Wasserwerks in Khabarovsk (Russland) wurde an einigen Brunnen eine intensive Manganfreisetzung beobachtet. Außerdem führte biologische Kolmation zu einem raschen Leistungsverlust und erforderte die Desinfektion der Brunnen. Die Auswertung der ersten 194 UEE-Zyklen eines Förderbrunnens und ergänzende Batchversuche ergaben, dass die Auflösung des im Grundwasserleiter vorhandenen, manganhaltigen Siderits die Ursache der Mn-Freisetzung war. Die Auflösungsprozesse hingen stark von der Korngröße des GWL-Materials und dem pH-Wert des Grundwassers ab. Die Filterkiesschüttung des Brunnens zehrte weniger als 1 % des infiltrierten Chlors und das Natriumhypochlorit drang ca. 2 bis 3,5 m in den Grundwasserleiter ein.
Das Wasserwerk Eggersdorf nutzt die UEE für die Voraufbereitung von eisenhaltigem Grundwasser und dient, entgegen den Empfehlungen für die UEE, der Abdeckung von Bedarfsspitzen. In einem Feldversuch wurde die mögliche Umnutzung der UEE-Brunnen für die dauerhafte Grundwasserförderung getestet. Die dabei aufgetretene Manganfreisetzung wurde auf die chemische Reduktion von abgeschiedenen Mangan(hydr)oxiden durch eisenhaltiges Grundwasser zurückgeführt.:Kurzfassung i
Abstract iii
Danksagung iv
Inhaltsverzeichnis v
Abkürzungsverzeichnis vii
1 Einleitung 1
1.1 Ausgangssituation 1
1.2 Motivation und Ziele 3
1.3 Gliederung der Arbeit 5
2 Auftreten und Verhalten von Mangan bei der Uferfiltration 6
2.1 Eintragspfade von Mangan in das Uferfiltrat 6
2.2 Einflussgrößen auf den Mangangehalt im Uferfiltrat 7
3 Erkundung eines neuen Uferfiltrationsstandortes in Embaba 9
3.1 Einleitung und Standortbeschreibung 9
3.2 Teufenabhängige Probennahme während des regulären Betriebes 9
3.3 Ursache der Manganfreisetzung und Bewirtschaftung des Standortes 10
4 Einfluss der Infiltrationsrate und der Temperatur auf die Manganfreisetzung aus der Elbsohle in Dresden 12
4.1 Einleitung und Standortbeschreibung 12
4.2 Einfluss der Temperatur auf die Manganfreisetzung 12
4.3 Einfluss der Infiltrationsrate auf die Manganfreisetzung 13
5 Freisetzung von Mangan beim Start einer UEE in Khabarovsk 15
5.1 Einleitung und Standortbeschreibung 15
5.2 Untersuchungen zur Ursache der Manganfreisetzung 15
5.3 Begrenzung der Leistungsabnahme der UEE-Brunnen 16
6 Manganfreisetzung bei der geplanten Umstellung des UEE-Wasserwerks
Eggersdorf auf kontinuierliche Förderung 18
6.1 Einleitung und Standortbeschreibung 18
6.2 Umstellung eines UEE-Brunnens auf dauerhafte Förderung 18
6.3 Ursache der Manganfreisetzung aus dem ehemaligen Reaktionsraum 19
7 Zusammenfassung und Ausblick 21
Literaturverzeichnis 24
Beiliegende Publikationen 29
Beiliegende Publikation 1 31
Beiliegende Publikation 2 53
Beiliegende Publikation 3 69
Beiliegende Publikation 4 83
Beiliegende Publikation 5 103
Beiliegende Publikation 6 135
Beiliegende Publikation 7 167
Beiliegende Publikation 8 189 / Bank filtration and Subsurface Iron Removal (SIR) are proven technologies for the natural subsurface pre-treatment of water. Depending on the water quality and the geochemical properties of the aquifer, redox reactions, sorption and dissolution or unfavorable well management can lead to increased manganese concentrations in both treatment options. Increased manganese concentrations often cause filter screen clogging of the well or deposits in pumps and standpipes. This can affect the long-term well operation and lead to higher costs of water treatment. Furthermore, increased manganese concentrations can cause a coloring of the water and must be lowered to < 0.05 mg/l during drinking water treatment. For waterworks operators, the knowledge about the source and the behavior of manganese is essential for an optimal operation.
The Egyptian capital Cairo faces a growing water demand. To evaluate a potential riverbank filtration site, depth-dependent sampling at existing test wells was carried out and sediment samples from the Nile riverbed were taken. The riverbed sediment showed elevated iron and manganese contents and was identified as cause of increased iron, manganese and ammonium concentrations in the riverbank filtrate.
For the bank filtration site Dresden-Tolkewitz, the impact of temperature and infiltration rate on the manganese release from the riverbed sediment of the Elbe river was investigated. The investigations were based on monitoring data of the years 2006 to 2016 and column experiments. The manganese release was primarily controlled by temperature, the infiltration rate was less important. With increasing temperature, the infiltration rate became even less critical. Manganese was released at water temperatures of 20 °C and infiltration rates of ≥ 0.3 m³/(m²×d).
During the start-up phase of a SIR waterworks in Khabarovsk, Russia, an intense manganese release was observed in several wells. In addition, biological clogging led to a rapid perfor-mance loss of the wells and required well disinfection. The evaluation of the first 194 SIR cycles of a production well and accompanying batch experiments indicated that the dissolution of the manganese-bearing siderite, which was present in the aquifer, caused the Mn release. The dissolution heavily depended on the grain size of the aquifer material and the pH of the groundwater. The filter gravel pack of the well consumed less than 1 % of the infiltrated chlorine and the sodium hypochlorite approximately penetrated between 2 and 3.5 m into the aquifer.
The waterworks Eggersdorf has been using SIR for the pre-treatment of ferrous groundwater and, contrary to general recommendations for SIR well operation, served for covering peaks in water demand. In a field trial, the possible conversion of the SIR wells for permanent groundwater extraction was tested. An observed manganese release was attributed to the chemical reduction of former precipitated Mn(hydr)oxides by iron-containing groundwater.:Kurzfassung i
Abstract iii
Danksagung iv
Inhaltsverzeichnis v
Abkürzungsverzeichnis vii
1 Einleitung 1
1.1 Ausgangssituation 1
1.2 Motivation und Ziele 3
1.3 Gliederung der Arbeit 5
2 Auftreten und Verhalten von Mangan bei der Uferfiltration 6
2.1 Eintragspfade von Mangan in das Uferfiltrat 6
2.2 Einflussgrößen auf den Mangangehalt im Uferfiltrat 7
3 Erkundung eines neuen Uferfiltrationsstandortes in Embaba 9
3.1 Einleitung und Standortbeschreibung 9
3.2 Teufenabhängige Probennahme während des regulären Betriebes 9
3.3 Ursache der Manganfreisetzung und Bewirtschaftung des Standortes 10
4 Einfluss der Infiltrationsrate und der Temperatur auf die Manganfreisetzung aus der Elbsohle in Dresden 12
4.1 Einleitung und Standortbeschreibung 12
4.2 Einfluss der Temperatur auf die Manganfreisetzung 12
4.3 Einfluss der Infiltrationsrate auf die Manganfreisetzung 13
5 Freisetzung von Mangan beim Start einer UEE in Khabarovsk 15
5.1 Einleitung und Standortbeschreibung 15
5.2 Untersuchungen zur Ursache der Manganfreisetzung 15
5.3 Begrenzung der Leistungsabnahme der UEE-Brunnen 16
6 Manganfreisetzung bei der geplanten Umstellung des UEE-Wasserwerks
Eggersdorf auf kontinuierliche Förderung 18
6.1 Einleitung und Standortbeschreibung 18
6.2 Umstellung eines UEE-Brunnens auf dauerhafte Förderung 18
6.3 Ursache der Manganfreisetzung aus dem ehemaligen Reaktionsraum 19
7 Zusammenfassung und Ausblick 21
Literaturverzeichnis 24
Beiliegende Publikationen 29
Beiliegende Publikation 1 31
Beiliegende Publikation 2 53
Beiliegende Publikation 3 69
Beiliegende Publikation 4 83
Beiliegende Publikation 5 103
Beiliegende Publikation 6 135
Beiliegende Publikation 7 167
Beiliegende Publikation 8 189
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Nutrient And Pathogen Removal In A Subsurface Upflow Wetland System Using Green Sorption MediaXuan, Zhemin 01 January 2009 (has links)
Due to environmental health and nutrient impact concerns, the conventional on-site sewage collection, treatment, and disposal systems are no longer able to meet the nutrient reduction requirements for wastewater effluent and may represent a large fraction of pollutant loads. The loads include not only nitrogen (N) and phosphorus (P), but also pathogens such as fecal coliform and E. coli which indicate the presence of other disease-causing bacteria flowing into aquatic system that adversely affect public health. A subsurface upflow wetland, which is an effective small-scale wastewater treatment system with low energy and maintenance requirements and operational costs, fits the current nutrient and pathogen removal situation having received wide attention throughout the world. Within this research study, a subsurface upflow wetland system (SUW), including four parallel SUW (three planted versus one unplanted), were constructed as a key component of the septic tank system receiving 454 liters per day (120 GPD) influent using the green sorption media along with selected plant species. It was proved effective in removing both nutrients and pathogens. During a one month test run, the planted wetlands achieved a removal efficiency of 84.2%, 97.3 %, 98.93 % and 99.92%, compared to the control wetland, 10.5%, 85.7 %, 99.74 % and 100.0 %, in total nitrogen (TN), total phosphorus (TP), fecal coli and E.Coli, respectively. Denitrification was proved to be the dominant pathway for removing N as evidenced by the mass balance and real-time PCR analyses. A simplified compartmental dynamics simulation model of constructed subsurface upflow wetlands was also developed to provide a dependable reference and tool for design of constructed subsurface upflow wetland.
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[en] DEEP PHYSICS-DRIVEN STOCHASTIC SEISMIC INVERSION / [pt] INVERSÃO SÍSMICA ESTOCÁSTICA COM APRENDIZADO PROFUNDO ORIENTADO À FÍSICAPAULA YAMADA BURKLE 28 August 2023 (has links)
[pt] A inversão sísmica é uma etapa essencial na modelagem e caracterização de reservatórios que permite a estimativa de propriedades da subsuperfície a partir dos dados de reflexão sísmica. os métodos convencionais usualmente possuem um alto custo computacional ou apresentam problemas relativos à não-linearidade e à forte ambiguidade do modelo de inversão sísmica. Recentemente, com a generalizaçãodo aprendizado de máquina na geofísica, novos métodos de inversão sísmica surgiram baseados nas técnicas de aprendizado profundo. Entretanto, a aplicação prática desses métodos é limitada devido a ausência de uma abordagem probabilística capaz de lidar com as incertezas inerentes ao problema da inversão sísmica e/ou a necessidade de dados de treinamento completos e representativos. Para superar essas limitações, um novo método é proposto para inverter dados de reflexão sísmica diretamente para modelos da subsuperfície de alta resolução. O método proposto explora a capacidade das redes neurais convolucionais em extrair representações significativas e complexas de dados espacialmente estruturados, combinada à simulação estocástica geoestatística. Em abordagem auto-supervisionada, modelos físicos são incorporados no sistema de inversão com o objetivo de potencializar o uso das medições indiretas e imprecisas, mas amplamente distribuídas do método sísmico. As realizações geradas com simulação geoestatística fornecem informações adicionais com maior resolução espacial do que a originalmente encontrada nos dados sísmicos. Quando utilizadas como entrada do sistema de inversão, elas permitem a geração de múltiplos modelos alternativos da subsuperfície. Em resumo, o método proposto é capaz de: (1) quantificar as incertezas das previsões, (2) modelar a relação complexa e não-linear entre os dados observados e o modelo da subsuperfície, (3) estender a largura de banda sísmica nas extremidades baixa e alta do espectro de parâmetros de frequência, e (4) diminuir a necessidade de dados de treinamento anotados. A metodologia proposta é inicialmente descrita no domínio acústico para inverter modelos de impedância acústica a partir de dados sísmicos pós-empilhados. Em seguida, a metodologia é generalizada para o domínio elástico para inverter a partir de dados sísmicos pré-empilhados modelos de velocidade da onda P, da velocidade da onda S e de densidade. Em seguida, a metodologia proposta é estendida para a inversão sísmica petrofísica em um fluxo de trabalho simultâneo. O método foi validado em um caso sintético e aplicado com sucesso a um caso tridimensional de um reservatório brasileiro real. Os modelos invertidos são comparados àqueles obtidos a partir de uma inversão sísmica geoestatística iterativa. A metodologia proposta permite obter modelos similares, mas tem a vantagem de gerar soluções alternativas em maior número, permitindo explorar de forma mais efetiva o espaço de parâmetros do modelo quando comparada à inversão sísmica geoestatística iterativa. / [en] Seismic inversion allows the prediction of subsurface properties from seismic reflection data and is a key step in reservoir modeling and characterization. Traditional seismic inversion methods usually come with a high computational cost or suffer from issues concerning the non-linearity and the strong non-uniqueness of the seismic inversion model. With the generalization of machine learning in geophysics, deep learning methods have been proposed as efficient seismic inversion methods. However, most of them lack a probabilistic approach to deal with the uncertainties inherent in the seismic inversion problems and/or rely on complete and representative training data, which is often scarcely available. To overcome these limitations, we introduce a novel seismic inversion method that explores the ability of deep convolutional neural networks to extract meaningful and complex representations from spatially structured data, combined with geostatistical stochastic simulation to efficiently invert seismicn reflection data directly for high-resolution subsurface models. Our method incorporates physics constraints, sparse direct measurements, and leverages the use of imprecise but widely distributed indirect measurements as represented by the seismic data. The geostatistical realizations provide additional information with higher spatial resolution than the original seismic data. When used as input to our inversion system, they allow the generation of multiple possible outcomes for the uncertain model. Our approach is fully unsupervised, as it does not depend on ground truth input-output pairs. In summary, the proposed method is able to: (1) provide uncertainty assessment of the predictions, (2) model the complex non-linear relationship between observed data and model, (3) extend the seismic bandwidth at both low and high ends of the frequency parameters spectrum, and (4) lessen the need for large, annotated training data. The proposed methodology is first described in the acoustic domain to invert acoustic impedance models from full-stack seismic data. Next, it is generalized for the elastic domain to invert P-wave velocity, S-wave velocity and density models from pre-stack seismic data. Finally, we show that the proposed methodology can be further extended to perform petrophysical seismic inversion in a simultaneous workflow. The method was tested on a synthetic case and successfully applied to a real three-dimensional case from a Brazilian reservoir. The inverted models are compared to those obtained from a full iterative geostatistical seismic inversion. The proposed methodology allows retrieving similar models but has the advantage of generating alternative solutions in greater numbers, providing a larger exploration of the model parameter space in less time than the geostatistical seismic inversion.
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Sustainability performance of multi-utility tunnels : Sustainability assessments for furthering knowledge and understandingBergman, Filip January 2022 (has links)
The multi-utility tunnel has received increased attention as an alternative method for the installation of subsurface infrastructure for the distribution of electricity, water, sewage and district heating. In previous research, the multi-utility tunnel (MUT) has been described as a more sustainable technology compared to the conventionally used technique where the cables and pipes are placed with open-cut excavation (OCE), especially when the entire life cycle is taken into account. This thesis aims to contribute to an improved understanding of MUT's sustainability performance in relation to conventional installation using open-cut excavation. This is done by using literature study, interview study and quantitative sustainability assessments to gain an understanding of the current state of knowledge. Furthermore, this thesis also focuses on how knowledge can be deepened with the help of quantitative sustainability assessments and the challenges of conducting this type of assessment. This thesis shows that the state of knowledge regarding MUT's sustainability performance is low and scattered, with a lack of a holistic approach. Direct economic performance has gained the most attention, followed by indirect and social impact, and the environmental impact has so far barely been assessed. The sustainability performance depends to a large extent on the conditions of the specific case, and these should be considered when assessing the technology. Quantitative assessments have the potential to help deepen the knowledge of the sustainability implications of using MUT. The characteristics of MUT have some similarities with other types of physical infrastructure. Similarities are that the systems are long-lived, have project conditions that affect sustainability performance, and impact a broad spectrum of actors. One difference to typical infrastructure systems is that the owner and management structure of MUT is, by design, more complex as several types of utility systems are in use. The characteristics of MUT give some practical considerations that need to be addressed: data availability, including practitioners; detailed data; transparency; and flexibility. This thesis highlights the complexity of assessing MUT´s sustainability performance and advocates that future studies should have a learning-oriented approach so that the knowledge level can collectively and gradually improve over time rather than focusing on decision-oriented studies. / <p><strong>Funding agencies:</strong> Kampradstiftelsen</p>
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DNA- and RNA- Derived Fungal Communities in Subsurface Aquifers Only Partly Overlap but React Similarly to Environmental FactorsNawaz, Ali, Purahong, Witoon, Herrmann, Martina, Küsel, Kirsten, Buscot, Francois, Wubet, Tesfaye 11 April 2023 (has links)
Recent advances in high-throughput sequencing (HTS) technologies have revolutionized
our understanding of microbial diversity and composition in relation to their environment. HTS-based
characterization of metabolically active (RNA-derived) and total (DNA-derived) fungal communities
in different terrestrial habitats has revealed profound differences in both richness and community
compositions. However, such DNA- and RNA-based HTS comparisons are widely missing for
fungal communities of groundwater aquifers in the terrestrial biogeosphere. Therefore, in this
study, we extracted DNA and RNA from groundwater samples of two pristine aquifers in the
Hainich CZE and employed paired-end Illumina sequencing of the fungal nuclear ribosomal internal
transcribed spacer 2 (ITS2) region to comprehensively test difference/similarities in the “total” and
“active” fungal communities. We found no significant differences in the species richness between
the DNA- and RNA-derived fungal communities, but the relative abundances of various fungal
operational taxonomic units (OTUs) appeared to differ. We also found the same set of environmental
parameters to shape the “total” and “active” fungal communities in the targeted aquifers. Furthermore,
our comparison also underlined that about 30%–40% of the fungal OTUs were only detected in
RNA-derived communities. This implies that the active fungal communities analyzed by HTS
methods in the subsurface aquifers are actually not a subset of supposedly total fungal communities.
In general, our study highlights the importance of differentiating the potential (DNA-derived) and
expressed (RNA-derived) members of the fungal communities in aquatic ecosystems.
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Imaging of Cardiovascular Cellular Therapeutics with a Cryo-imaging SystemSteyer, Grant January 2010 (has links)
No description available.
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Subsurface Facies Analysis of the Devonian Berea Sandstone in Southeastern OhioGarnes, William Thomas 08 December 2014 (has links)
No description available.
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Subsurface Facies Analysis of the Clinton Sandstone, Located in Perry, Fairfield, and Vinton CountiesStouten, Craig A. 19 November 2014 (has links)
No description available.
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GIS Uses for Modeling Subsurface Conditions in Ohio Coal MinesKleski, Kurt W. January 2017 (has links)
No description available.
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Characterization of Agricultural Subsurface Drainage Water Quality and Controlled Drainage in the Western Lake Erie BasinPease, Lindsay Anne 28 September 2016 (has links)
No description available.
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