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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.
151

Traitement par oxydation chimique de sols de friches industrielles contaminés par des Hydrocarbures Aromatiques Polycycliques / Investigation on treatment by chemical oxidation for brownfield contaminated with Polycyclic Aromatic Hydrocarbons

Lemaire, Julien 04 November 2011 (has links)
Contrairement aux idées reçues, le sol est une ressource naturelle non renouvelable menacée. La réhabilitation des friches industrielles polluées aux HAP, toxiques et persistants, représente donc un enjeu majeur. Les techniques traditionnelles ne sont pas toujours très appropriées, c’est pourquoi ce travail vise à étudier la pertinence de l’oxydation chimique in situ, habituellement utilisé pour le traitement de nappes contaminées par des polluants moins récalcitrants (COHV, BTEX). Il s’inscrit dans le cadre du projet OXYSOL (ANR-PRECODD) destiné à construire une filière complète de traitement in situ et de refonctionnalisation. Ce travail a consisté à étudier et optimiser ces performances en travaillant avec la terre d’une ancienne cokerie. Ensuite, l’objectif a été de mettre en évidence les principaux paramètres limitants en utilisant différentes terres polluées contrastées. Tout d’abord, les expériences en systèmes fermés ont conduit à sélectionner les deux oxydants les plus adaptés: le réactif de Fenton et le persulfate activé. Ensuite, l’oxydation a été étudiée en systèmes ouverts de l’échelle du laboratoire à l’échelle pilote afin d’optimiser les conditions d’injection. Les résultats obtenus, comparables à ceux en systèmes fermés, ont mis en évidence le caractère très limitant de la faible disponibilité des HAP ainsi que l’existence d’une fraction impossible à atteindre (taux d’abattement inférieur à 50%). Enfin, les derniers résultats ont corroboré la relation entre l’âge de la pollution, la disponibilité des HAP et les performances de l’oxydation chimique. Par ailleurs, ils ont permis d’expliquer et hiérarchiser les effets limitants de différents paramètres (disponibilité des HAP, teneur en carbone organique, en carbonate, pH, structure des HAP et mode d’injection) en fonction de l’oxydant utilisé. Les recherches effectuées soulignent l’importance d’étudier les performances de l’oxydation chimique directement avec la terre prélevée sur le site pollué. / Contrary to general belief, soil is a threatened nonrenewable natural resource. Consequently, the restoration of brownfields contaminated with PAHs, that are toxic and persistent contaminants, is a major challenge. Usual techniques are not always appropriate, so the aim of this work is to study the relevance of in situ chemical oxidation (ISCO), usually used for groundwater treatment contaminated with less recalcitrant pollutants (CVOCs, BTEX). It is a part of OXYSOL project aiming at the conception of a global treatment pathway including in situ remediation and soil construction. This work was to study and optimize oxidation efficiency with the soil of a former coking plant. Then, objective was to highlight main limiting factors using different contrasting soils. First, experiments were run in batch systems to select both most suitable oxidants: Fenton's reagent and activated persulfate. Then oxidation was performed in flow systems from the bench to the pilot scale in order to optimize injection parameters. Results, comparable to those obtained in batch systems, showed that oxidation efficiency was strongly limited because of low PAHs availability and highlighted presence of unavailable PAHs (degradation ratio lower than 50%). The last results confirmed the relationship between pollution aging, PAHs availability and chemical oxidation performance. Moreover, they help to understand and compare the influence of different limiting factors (PAHs availability, organic carbon content, carbonate content, pH, PAHs structure and injection method) depending on the oxidant. The research underlined the need to investigate chemical oxidation performance with soil samples collected from contaminated sites and not with spiked soils.
152

Groundwater flow and contaminant transport in an alluvial aquifer: in-situ investigation and modelling of a brownfield with strong groundwater - surface water interactions

Batlle Aguilar, Jordi 19 September 2008 (has links)
The continuous demand on new residential and economic areas of the modern society has to face up with problems posed by polluted sites related to former industrial activities, typically located in suburbs areas. These sites, known as brownfields, are often located nearby navigable rivers to facilitate transport operations of industrial manufacturing, which increase their potential environmental threat due to the possible migration of pollutants in groundwater to surface water bodies through groundwater discharge. In this context, the objective of this research, performed in the scope of the FP6-IP AquaTerra project, was to contribute to a better assessment of the risk of groundwater contaminant dispersion for a brownfield located next to the Meuse River (Belgium), in a context where strong groundwater - surface water interactions prevail. The brownfield of interest corresponds to the site of the former coke factory of Flémalle. Resulting from industrial activities, soil and groundwater located in the alluvial aquifer are heavily contaminated with various types of organic (BTEX, PAHs, mineral oils...) and inorganic (As, Zn, Cd...) pollutants. To do so, detailed characterisation campaign was performed, consisting of, on the one hand, classical field experiments such as pumping tests, injection tests and tracer experiments; on the other hand, advanced and original field experiments such as detailed monitoring of groundwater - surface water interaction and dynamics, and the development and application of an innovative tracer technique, the Finite Volume Point Dilution Method (FVPDM), used to quantify and monitor groundwater fluxes. Monitoring and field works data was subsequently used to develop and calibrate a groundwater flow model using the finite difference code MODFLOW, with an automatic parameter estimation approach based on an original combined regional scale (zonation) and local scale (pilot points) approach. A transport model was also developed using MT3DMS and calibrated using tracer experiments performed in the brownfield. This groundwater flow and transport model was used to better quantify the dynamics of groundwater - surface water interactions and to model various scenarios of contaminant dispersion through the aquifer - river system. For these scenarios, benzene was considered because it is one of the main pollutants encountered in the site, its large solubility and mobility in groundwater and its acute toxicity. These scenarios were established considering various groundwater flow conditions (steady state vs. transient) and various hydrodispersive processes possibly affecting the mobility of benzene in groundwater, namely advection, hydrodynamic dispersion, sorption - desorption and, as evidenced by the research results of the University of Neuchâtel (Switzerland), benzene degradation under sulphate reducing conditions. These simulations indicate that benzene attenuation is mainly controlled by ongoing benzene degradation processes, aquifer heterogeneity and river stage fluctuations. Based on this analysis, the risk of benzene dispersion is low, and monitored natural attenuation (MNA) is a valuable option with (1) monitoring benzene at control planes downstream from the sources; (2) further investigation on risk of sulphate depletion in the alluvial aquifer; and (3) further investigation on mobilisation/immobilisation of heavy metals related to dynamics of organic pollutant plumes.
153

Velayat park : En plats för gränsöverskridande möten mellan människor med olika socioekonomisk status

Abbasi, Hamon January 2017 (has links)
Tehran, the capital of Iran has undergone major urbanization in the last century, which has caused uncontrollable urban growth. Poor regulation and control of this growth has given rise to environmental problems including high air and water pollution. In turn, this has led to urban growth towards the mountains in the north, where the environment is better. However, this pressure to develop in the north has increased segregation of the city and created a clear social division of class between the northern and southern parts of the City. In light of this, and in the context of Tehran as an extremely dense city with limited green space, the City sees a possibility in transforming an unused military airport in the southern districts of the city into a new urban park. This master thesis explores how to reclaim the 270Ha former airfield and develop it as an urban park with strengthened links to surrounding neighbourhoods. The work aims to gain an understanding of how large vacant areas can become successful public areas and green places in the community. The work is based on urban theory and site analysis and brings forward design proposals for the park. Analysis work is divided into an investigative and exploratory stage. The investigative part includes literature studies, data collection and mapping of the city’s urban morphological development, taking into account physical and socio-economic processes. The exploratory part consisted of inventories, site studies and interviews in Tehran, as well as integration analysis with space syntax to explore accessibility and connections in the new park. Throughout the study shows how and why the city has evolved and highlights a connection between living in the southern districts, which are low-income areas, with also having poor access to public and recreation areas. This analysis forms the foundations for the design proposal, visualizations and programs presented about how the area can be designed as a new urban city park. In conclusion, the study highlights that in order to be able to develop new places or renew existing area’s, consideration must be given to urban morphological development. This includes the socio-economic and socio-ecological process. It further concludes, that a ecological viewpoint together with a understanding of the physical environment, the urban landscape identity and the need of people in the context needs to be brought together to plan and create parks and urban spaces
154

Biomonitoring environnemental et sanitaire des sols pollués par les éléments traces métalliques / Sanitary and environmental biomonitoring of polluted soil by metallic trace elements

Lévèque, Thibaut 24 October 2014 (has links)
Dans un contexte où les préoccupations environnement-santé sont croissantes à l’échelle globale. Améliorer la compréhension des mécanismes de biodisponibilité et d’(éco)toxicité des polluants métalliques persistants est un enjeu prioritaire, notamment en raison de leur omniprésence observée dans les écosystèmes en relation avec leur compartimentation et spéciation . Le ver de terre est utilisé pour évaluer la qualité des sols ; de plus cet organisme du sol de par ses activités de bioturbation a une influence sur les cycles biogéochimiques. Des tests d’écotoxicité en conditions contrôlées sur vers de terre ont donc été réalisés avec différents sols et espèces de vers. Puis une étude d’impact sur les communautés de vers a été effectuée sur un site pollué présentant un gradient de concentration. L’influence de la bioturbation du ver sur la phytodisponibilité des polluants a été étudiée grâce à des expériences en mésocosmes. Finalement, des mesures de bioaccessibilité des polluants ont été réalisées in vitro sur des sols et végétaux pollués dans différents contextes : friches industrielles, jardins potagers, terrain de sport. L’objectif étant d’étudier le lien entre biodisponibilité pour l’homme, caractéristiques des sols et contexte de pollution. Deux approches complémentaires ont été développées : recherche scientifique liés aux mécanismes et développement d’outils, de procédures pratiques utilisables par les gestionnaires et évaluateurs de risques. L’écotoxicité des métaux et métalloïdes (notés ETM) sur les vers de terre n’est pas simplement régie par leurs concentrations totales, mais dépend fortement des caractéristiques physico-chimiques des sols. Par ailleurs, l’analyse des communautés de ver de terre présentes sur un site contaminé permet d’évaluer la qualité des sols puisqu’on constate un impact sur les l’abondance, la diversité et le taux de juvénile des vers. De plus, la bioturbation du ver de terre augmente significativement la biodisponibilité des ETM pour les plantes potagères telles que la laitue. Finalement, la bioaccessibilité humaine des ETM est régi par de nombreux facteurs liés en particulier au contexte de pollution. Cette fraction bioaccessible des ETM est directement responsable de leur cytotoxicité sur les cellules intestinales. Ces différents résultats ont été complétés par des études mécanistiques (IR, EXAFS, XANES, µ-XRF). / In a context where environmental health concerns are globally increasing. Improve understanding of the mechanisms and bioavailability (eco) toxicity of persistent metals pollutants is a priority, especially because of their observed omnipresence in ecosystems in relation to their compartmentation and speciation. The earthworm is used to assess soil quality; moreover this soil organism through its bioturbation activities affects biogeochemical cycles. Ecotoxicity tests under controlled circumstances on earthworms have been conducted with different soils and worms’ species. Then an impact study on earthworms’ communities was conducted on a polluted site showing a concentration gradient. The influence of earthworms’ bioturbation on phytoavailability of pollutants was studied through experiments in mesocosms and Rhizotest. Finally, in vitro measures of pollutants bioavailability were performed on polluted soils and plants in different contexts: brownfields, gardens, sports field. The objective is to study the link between bioavailability for humans, soil characteristics, context of pollution and toxicity. Two complementary approaches have been developed: scientific research related to the mechanisms and development of tools, practical procedures which could be used by managers and risk assessors. Ecotoxicity of metals and metalloid (denoted ETM) on earthworms is not simply governed by their total concentrations, but strongly depends on the physico-chemical characteristics of soils. Furthermore, analysis of earthworm communities from a contaminated site can evaluate the quality of soil since seen an impact on the abundance, diversity and rate of juvenile worms. In addition, earthworms’ bioturbation significantly increases the bioavailability of ETM for vegetable plants such as lettuce. Finally, the human bioaccessibility of ETM is governed by many factors, in particular the context of pollution. The bioaccessible fraction of ETM is directly responsible for their cytotoxicity on intestinal cells. These results were complemented by mechanistic studies (IR, EXAFS, XANES, μ-XRF).
155

PERLA Ústí nad Orlicí / PEARL Ústí nad Orlicí

Annová, Denisa January 2016 (has links)
The subject of the diploma thesis is to design reclamation of brownfield PERLA 01 in Ústí nad Orlicí. The construction program consists conversion of existing building to assembly hall, gallery, tourist centre, sheltered workshop, rentable space, office building. New building is Start up centre. The project design a character of public space and a new square.
156

Ekonomické hodnocení veřejného projektu zaměřeného na revitallizaci brownfieldu / Economic Evaluation of Public Project oriented on Revitalization of Brownfields

Sabo, Jakub January 2018 (has links)
Thesis deals with issue of „brownfields“ in mining sphere and their regeneration. The work is splitted into two parts, theoretical and practical. The theoretical part contains basic economic terms, relative to theme of the thesis and basic information about brownfields and their dividing. The practical part contains valorization of social-economical utilization on the study case of brownfield mining area Most-Ležáky in north side of Czech republic. The aim of this thesis is to assess, if is the revitalization of this specific brownfield, and similar brownfields, social-economically effective. The assessment contains social-economic benefits and costs of specified area revitalization.
157

Rehabilitace historického jádra a přilehlého okolí města Kyjov se zaměřením na veřejný prostor / The Rehabilitation of the historical center and adjacent surroundings of Kyjov with a focus on the public space

Kratochvilová, Jana January 2018 (has links)
The diploma thesis deals with the construction and activation of the territory in connection with the historical center of Kyjov. Part of the proposal was to work with an existing urban brownfield and an extensive park, which accounts for almost half the area under consideration. The goal, as I set out in my work, is to activate the territory and design an urban sprawl with a suitable functional structure. The proposed design respects the context and character of the site in a modern and sustainable manner. The principles followed in my work are based on the current urban and city-forming rules. I have put an emphasis on the human scale, the priority of pedestrians over traffic, and especially the shortcomings and needs in the territory that arise from the analysis. The draft concept is based on the permeability and interconnection of the individual parts of the city, the insertion of a new public space and the completion of the city block. The new urban sprawl clearly defines the street, completes the boundaries and makes the most of the area on the released land. The newly designed buildings are residential and multi-functional houses with active parterres. Part of the proposal is the revitalization of the city park, which explores its hidden potential. The basic step is to remove obstacles in the permeability of the park and to highlight its strengths, such as the flowing river Kyjovka, healthy large trees and the size of the park itself.
158

Brněnské brownfieldy u řeky Svitavy / Brno brownfields by the Svitava river

Macháček, Tomáš January 2018 (has links)
The theme of the diploma thesis „Brno brownfields by the Svitava River“ Is design of contemporary city structure in Brno Husovice. The theisis deals with the analysis of the current situation, definition of problems and opportunities in the location and the design, based on these researches. Studied area is located on the riverbank of the Svitava River and is defined by Provazníkova, Dukelská třída and Svitavské nábřeží streets. In these days there are mostly located brownfields of the previous industry parks, storage spaces and development of family houses. The design puts emphasis on the gentle merge with the urban structure of the old Husovice and focuses on using modern architectonic and urban approaches as well, for example on multifunctionality of buildings. The riverbank is revitalised and attractive features are designed here, like the footbridges conneting both river sides and sittable stairs. These designs provide space for leisure time and a water control during the floods as well. The traffic solution is concerned on the design of the new Nová Dukelská street, connecting formerly Zbrojovka industry park and Provazníkova street.
159

Brněnské brownfields u řeky Svitavy / Brno brownfields by the Svitava river

Flössler, Libor January 2018 (has links)
Brownfield in Brno by the Svitava river. Proposal of conversion and completing of a part of the area in Brno – Husovice district, where you can find brownfield, as e.g. an old hall of former Zetor company. The goal is to design a functional district with respect to the original housing development. The territorial unit is designed so that it respects surrounding housing development and improves transportation situation. It complies with transportation connection to future reconstruction of Zbrojovka premises, for which a proposal is being designed. The main target is to create a comfortable place to live in and to cover basic needs of every person, to design interesting places for relaxation, cultural life, provide sports facilities and raise number of job opportunities in this area. The goal of this project is also to create a diverse place for living. Its meant for people from different social backgrounds and for people who use cars both with low frequency or who use them on a daily basis.
160

Revitalizace areálu Filmových ateliérů Zlín / Revitalization of Film studios in Zlín

Kubačka, Jan January 2015 (has links)
This diploma thesis deals with urban study of revitalization of complex of former film studios on an area of approximately three kilometers south of the center of Zlín, in the town district which is called Kudlov. The complex has been constructing since the thirties of the last century, however nowadays it is no longer determined to its original function. In this thesis, the optimalization of current state, the completion of several building and the area expansion of the park on the West are designed. Great emphasis was given on the largest possible multi-functionality, in addition to the main function of living in apartment houses, the area is complemented by commerce, leasable manufacturing facility, an outdoor sport complex and the already mentioned park. The urban concept reflects the traditional urbanism of the city of Zlín, it means a periodical grid of structure and a unity of shapes and materials.

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