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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.
41

"A utilização de turfa como adsorvente de metais pesados. O exemplo da contaminação da Bacia do Rio Ribeira de Iguape por chumbo e metais associados" / "The utilization of peat as heavy metal adsorbent. The example of the contamination of Ribeira do Iguape River catchment by lead and associated minerals"

José Guilherme Franchi 19 November 2004 (has links)
Este trabalho teve como objetivos principais a caracterização da mina de turfa de Eugênio de Melo, localizada no Estado de São Paulo, região do Vale do Rio Paraíba do Sul, bem como uma amostra representativa do seu minério. Esta amostra foi testada sob duas condições – in natura e tratada com ácido clorídrico – como adsorvente de metais pesados visando a aplicação do minério em processos de tratamento de efluentes líquidos. Adotaram-se como estudos de caso lixívias obtidas a partir de resíduos da mineração de sulfetos de chumbo e metais associados existentes na região do alto curso do Rio Ribeira de Iguape, geradas em laboratório. Tais depósitos encontram-se sob a forma de extensos corpos às margens de importantes drenagens, circunscritas à região de Adrianópolis (PR). A possibilidade de liberação dos metais pesados presentes nestes depósitos para o ambiente foi avaliada através de estudos granulométricos, mineralógicos e químicos de uma coluna amostrada num destes depósitos. Os teores dos metais presentes nas lixívias enquadraram-nas como não passíveis de descarte para o ambiente sem tratamento prévio, segundo a legislação estadual e federal que regem o assunto. Os resíduos da mineração aqui estudados, compreendendo rejeitos das plantas de concentração mineral e escórias de uma unidade de metalurgia, foram caracterizados como Classe I (perigosos) de acordo com metodologia adotada pela Associação Brasileira de Normas Técnicas. A capacidade adsortiva da turfa para 5 dos metais presentes nas lixívias foi avaliada através de experimentos de equilíbrio, conduzidos em batelada, em sistemas de componente único. Os dados obtidos apresentaram ajuste ao modelo cinético de Langmuir. A afinidade química da turfa revelou-se mais forte para chumbo, cobre e cádmio, e mais reduzida para zinco e manganês. Cálcio e magnésio, provenientes dos metadolomitos hospedeiros das mineralizações sulfetadas, apresentam-se em grande quantidade nas lixívias e foram caracterizados como elementos interferentes no processo adsortivo, que se mostrou, também, influenciado pelo pH e temperatura de realização dos ensaios. As lixívias foram submetidas a 5 ciclos sucessivos de contato com a turfa para se avaliar a eficiência do processo adsortivo em enquadrá-las à legislação ambiental de descarte. Nesta simulação de tratamento de efluentes por bateladas, em situação de adsorção competitiva, a turfa revelou-se um bom adsorvedor para chumbo e cobre. Seu modesto desempenho relativamente a cádmio, zinco e manganês posiciona-a como insumo adequado a processos de descontaminação de efluentes líquidos preferencialmente após etapa de tratamento primário. / This work has as main objectives the characterization of the Eugênio de Melo peat mine, located in the Paraíba do Sul River Valley, State of São Paulo, as well as a representative sample of its ore. This sample was tested as an absorbent material in two conditions – both in natura and treated with hydrochloric acid – in order to assess its use in liquid effluent treatment process. It were adopted as case studies lab generated leaches obtained from mining residues of lead and associated metals sulfides present at the upper course of the Ribeira do Iguape River region, accumulated as huge deposits close to important drainages, near the Adrianópolis (PR) region. The possibility of the heavy metals’ environmental release from those deposits was assessed through grain size distribution, mineralogical and chemical approaches. These studies were led in a vertical profile surveyed in a specified deposit. The leaches’ heavy metal contents surpass the limits set by both state and federal environmental permits, so they are not allowed for discharge to the environment without prior treatment. The mining residues studied here – mining wastes and metallurgical slags – were characterized as Type I (perilous material) according to Brazilian Guidelines for Residues Classification set by Brazilian Association for Technical Standards. The peat’s adsorptive capacity was assessed for 5 of the heavy metals present in the leaches by means of batch equilibrium essays conducted in single component systems. The data of these experiments fitted to Langmuir’s kinetic model. The chemical affinity of the peat was stronger for lead, copper and cadmium, and weaker for zinc and manganese. Calcium and magnesium derived from metadolomites that hosts sulfide mineralization are in great amount in the leaches. They were identified as interferential constituents to the adsorptive process, which are also affected by the pH and temperature of the assays. The leaches were undergone to 5 cycles of contact with peat in order to assess if the adsorptive process fit them to the legal discharge environmental standards. In this simulation of batch effluent treatment by means of competitive adsorption, the peat revealed itself as a good adsorbent for both lead and copper. The weak adsorptive performance for cadmium, zinc and manganese ranked peat only as a qualified supplies to remediation process entailing liquid effluents, preferably after primary treatment process.
42

O impacto da resolução CONAMA 273/00 na gestão das áreas contaminadas por postos de combustíveis do Estado de São Paulo / The impact of CONAMA resolution 273/00 on petrol stations contaminated sites management in São Paulo State

Anie Gracie Noda Amicci 29 April 2010 (has links)
O problema ambiental das áreas contaminadas foi por muito tempo negligenciado. No Estado de São Paulo as primeiras medidas efetivas de gestão do tema foram tomadas em 2000, em parte motivadas pela ocorrência de acidentes em postos de combustíveis. A publicação da resolução CONAMA 273/00, que instituiu a obrigatoriedade do licenciamento dos postos de combustíveis (novos e em operação), deu mais destaque ao assunto, pelo menos no Estado de São Paulo, onde sua implementação revelou inúmeros passivos ambientais em postos de combustíveis. Estudar este e outros impactos desta resolução na gestão das áreas contaminadas por postos de combustíveis foi o objetivo deste trabalho. Isto foi feito por meio da descrição da gestão de áreas contaminadas por postos de combustíveis, antes e depois da resolução, e de seus resultados divulgados pela CETESB. A análise qualitativa da gestão foi feita com base nos instrumentos de gestão utilizados e encontrou uma gestão centrada em instrumentos de comando e controle, mas que se complementa com instrumentos econômicos e acordos voluntários. A análise quantitativa foi feita com base nos dados secundários divulgados pela CETESB e aponta, apesar de tendências de melhoria, para resultados ainda incipientes, com baixos percentuais de postos de combustíveis licenciados, reduzido número de áreas remediadas e pequeno decréscimo no número de acidentes em postos de combustíveis. / Contaminated sites represent an environmental problem that was neglected for a long time. In São Paulo State this problem was first addressed in 2000, partially due to environmental accidents in petrol stations. CONAMA 273/00, a resolution that enforced petrol stations (both new and running businesses) to require permits, attracted more attention to the matter, at least in São Paulo State, where its implementation revealed various petrol stations contaminated sites. This and other impacts of this resolution on petrol stations contaminates sites management are the core subject of this thesis. The study consists on the description of the management program before and after the resolution, as well as the results obtained, which were made public by CETESB. The qualitative analysis of the management program was based on the instruments used, it revealed a command and control approach, which makes use of complimentary instruments such as economic and voluntary ones. The quantitative analysis based itself on secondary data obtained at CETESB and, although the positive trend of the results, it still indicates low percentages of petrol station with permit, a reduced number of cleaned-up sites and a small decrease in the number of accidents in petrol stations.
43

Untersuchungen zur Quantifizierung der Grundwasserimmission von polyzyklischen aromatischen Kohlenwasserstoffen mithilfe von passiven Probennahmesystemen

Börke, Peter 30 March 2007 (has links)
Kern der Arbeit bildete die Entwicklung einer Fluxmeter-Passivsammlereinheit für hydrophobe organische Substanzen im Grundwasser kontaminierter Standorte sowie deren Testung im Feld. Ferner kamen Keramik-Dosimeter unter identischen Feldbedingungen zum Einsatz. Die Ergebnisse der beiden passiven Sammelsysteme wurden mit herkömmlicher Grundwasserprobennahmetechnik mithilfe von Unterwassermotorpumpen verglichen und bewertet. Grundlage für den Einsatz der Passivsammlereinheit als „mass flux meter“ bildete die Kenntnis über den Volumenstrom im Bohrloch und den reduzierten Volumenstrom in der Passivsammlereinheit und andererseits über die räumliche Verteilung der hydraulischen Durchlässigkeit und der daraus resul¬tierenden heterogenen Geschwindigkeitsverteilung bzw. der Volumenströme über so genannte Kontroll¬ebenen bzw. Teilbilanzräume. Anhand numerischer Modelluntersuchungen konnten der Filterwiderstand der Passivsammlereinheit und die Strömungsverteilung in Modellkontrollebenen und im Feld näherungsweise bestimmt werden. Die Bestimmung des Volumenstromes des untersuchten Standortes wurde zum einen mithilfe von numerischen Modelluntersuchungen an stochastisch generierten quasi-3-dimensionalen Modellen mit hydro¬dynamischen Randbedingungen und kF-Wertverteilungen aus dem Feld und zum anderen mithilfe von Einbohrlochverfahren durchgeführt. Als Einbohrlochverfahren kamen zum einen ein optisches Kolloid-Logging (Grundwasserfluss-Visualisierungssystem) und zum anderen ein modifiziertes Fluidlogging-Verfahren mit Hilfe eines Salztracers zum Einsatz.
44

Contamination de sols par des éléments traces métalliques en zone méditerranéenne côtière : études de leur mobilité et du transfert à la phytocénose.

Testiati, Eti 22 November 2012 (has links)
Les objectifs de cette thèse ont été de contribuer à l'évaluation des niveaux de contamination en éléments traces métalliques et métalloïdes (ETMM) des sols du site de l'ancienne fonderie de plomb de l'Escalette (sud-est de Marseille), d'en approcher les processus de transport et transfert dans l'environnement en particulier leurs mobilités dans le sol et leurs transferts aux plantes. La contribution à l'établissement d'une cartographie de la contamination sur un périmètre plus vaste que celui de l'usine (zone des Calanques) a permis de mettre clairement en évidence l'impact de cette dernière. Sur le site industriel, les formes et niveaux de contamination des sols diffèrent d'une zone à l'autre. Les sols formés en surface des crassiers se caractérisent par leurs fortes teneurs en Cu, Zn et Pb, dont les fractions mobilisables sont notables (2 à 30%), l'influence des scories est nette. Les sols prélevés à proximité de la cheminée présentent les plus fortes contaminations en Pb, Sb et As, avec de 10 à 30% de fractions mobilisables. Cette contamination est liée aux émissions anciennes via la cheminée rampante mais aussi à la dégradation de cette dernière. Le potentiel de libération des éléments As et Sb des sols de ces 2 zones conduirait à leurs stockages dans des décharges pour déchets dangereux. Les essais de solubilisation en milieu acide ont mis en évidence des risques pour la santé par ingestion concernant Pb et As. Les zones en proche périphérie de l'usine sont moins impactées mais sont néanmoins considérées comme fortement contaminées. G. alypum et R. officinalis, présentes sur le site, sont tolérantes aux ETMM et peuvent les accumuler. / The overall objective of this thesis was to contribute to the assessment of the level of contamination by trace metals and metalloids (TMM) on the site of Escalette (a former lead smelter in southeastern Marseille). The study of TMM transfer and transport processes on this site, taking into account their mobility in the soil and their transfer to plants, was a specific objective. The mapping of TMM contamination in an extended area around the factory site (on Calanques zone) has clearly highlighted the impact of the former industry. So, on the Escalette site, forms and levels of soil contamination differ from one area to another. Soils formed on the surface of the slag deposits are characterized by high levels of Cu, Zn and Pb, whose mobilizable fractions are significant (2-30%), showing a clear influence of slag. Soils collected near a chimney creeping uphill the slope, present the highest contamination levels in Pb, Sb and As, with from 10 to 30 % of mobilizable fractions. This contamination is linked to emissions through the damaged chimney but also to the degradation of this latter. The potential release of As and Sb from the soils of these two areas requires that these soils must be disposed of in landfills for hazardous wastes and their solubilization in acid medium have highlighted the health risks by ingestion for Pb and As. On areas in near periphery of the smelter, soils are less affected but must be still considered heavily contaminated. G. alypum and R. officinalis were observed on the site. They are tolerant and can accumulate TMM. Concentrations in roots were significantly correlated with the concentrations in soils, except for Cu.
45

A importância dos fatores ambientais na reutilização de imóveis industriais em São Paulo. / Considering soil quality in industrial sites redevelopment in São Paulo.

Ayres da Silva, Anna Carolina Marques 30 September 2002 (has links)
O presente trabalho aborda uma questão ainda relativamente nova, mas de urgente reflexão: a reutilização de imóveis industriais, considerados hoje, áreas potencialmente contaminadas (AP) por atividades não industriais. Objetiva documentar a postura mais freqüentemente utilizada no Brasil quando da reocupação da implantação de novos usos em imóveis industriais desativados, adotando-se como parâmetro o município de São Paulo. Busca averiguar se, em algum momento deste processo, há qualquer consideração sobre a possibilidade da existência de passivo ambiental, dada a natureza industrial da atividade anteriormente desenvolvida no imóvel. Parte da hipótese que os agentes envolvidos nesse processo de mudança de uso (incorporadoras, construtoras, etc) ignoram ou desconsideram a possível existência de contaminação no imóvel. A metodologia consistiu na seleção dos imóveis, a partir de uma base cartográfica (4 cartas – escala 1: 25.000 da EMPLASA) que registrava o uso do solo em 1980. Posterior visita ao campo e registro do uso atual destes imóveis. Os que apresentaram um novo uso não industrial foram analisados e se dentro dos parâmetros desejados, sujeitos a uma entrevista. O resultado das entrevistas comprovou a hipótese inicial. Conclui-se que, a reincorporação destes imóveis ao tecido urbano dá-se sem qualquer preocupação quanto à existência de uma possível contaminação do solo, dos aqüíferos ou das instalações se reaproveitadas. Mesmo se, durante a construção do novo empreendimento, tenham sido observados indícios de uma provável contaminação. Não há qualquer interesse na investigação da qualidade do solo e água, além do usual, para execução das fundações. Do ponto de vista dos agentes envolvidos, somente a exigência de um órgão público justificaria tal atitude. / This research refers to a very new problem, which needs urgent reflection and response: the new land uses in industrial areas, considered potentially contaminated. The research intends to define which is the more common attitude in Brazil for redevelopment of decommissioning industrial plants areas, focused on São Paulo city. It aims to examine the process of redevelopment projects, in order to discover if there is any consideration about the environment quality during the land uses changes. It takes as hypothesis that the agent involved in land uses changes process ignore completely the existence of contaminated sites. The methodology was grounded and developed by using charts (4 charts- scale 1:25.000 –.EMPLASA), which indicated the industrial plants in 1980. Later visit on land to verify their current uses. The agents involved in the installation of new non-industrial establishments were interviewed about the process. In summary, one can say that the reintegration of these decommissioning industrial areas is done without any kind of deeply concerns about the contaminated sites, or the impact of the past industrial activities on the groundwater quality, or in the abandoned installations. There isn’t any further interest in order to investigate the possibility of environmental liabilities and consequent risks and hazards.
46

Fate and exposure assessment of PCDD/Fs at contaminated sites

Åberg, Annika January 2008 (has links)
<p>Polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzo-furans (PCDFs) belong to the most toxic compounds known to science and they are defined as Persistent Organic Pollutants (POPs) under the Stock-holm Convention. The general human exposure to PCDD/Fs is primarily through dietary intake. The importance of contaminated sites as secondary PCDD/F sources (i.e. sources that once received its contamination from a primary source) are getting increased attention. To be able to assess the risks for human exposure at PCDD/F contaminated sites, the environmen-tal distribution of PCDD/Fs and the potential mobilization between dif-ferent environmental media (e.g. food chain transfer) must be known. The primary aim of the work presented in this thesis was to investigate human exposure pathways associated with PCDD/F contaminated sites by combining field measurements and modeling. Site specific field measurements were made at a PCDD/F contaminated site in Sweden and multimedia modeling scenarios were evaluated against site specific data and national reference data.</p><p>The results show that the congener distributions in exposure media affected by contaminated soil may differ significantly from the distribu-tions found in media from reference locations. Higher chlorinated PCDD/Fs may be transferred into food chains where they contribute to a large fraction of the toxic equivalent concentration (TEQ). Ingestion of locally produced animal food may be an important exposure pathway al-ready at low or moderate PCDD/F soil concentrations. However, the con-gener composition of the source is critical for the exposure. The signifi-cance of the individual exposure routes varies depending on e.g. the spatial distribution and magnitude of the soil contamination, the pro-perties of the exposure media and the human behavior. Multimedia mo-deling can be used in risk assessments as long as model algorithms and model parameters are representative for the superhydrophobic properties of PCDD/Fs. However, selection of physical-chemical PCDD/F properties is a challenge due to large variation in reported values. For some proper-ties, data is scattered or completely lacking</p>
47

Fate and exposure assessment of PCDD/Fs at contaminated sites

Åberg, Annika January 2008 (has links)
Polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzo-furans (PCDFs) belong to the most toxic compounds known to science and they are defined as Persistent Organic Pollutants (POPs) under the Stock-holm Convention. The general human exposure to PCDD/Fs is primarily through dietary intake. The importance of contaminated sites as secondary PCDD/F sources (i.e. sources that once received its contamination from a primary source) are getting increased attention. To be able to assess the risks for human exposure at PCDD/F contaminated sites, the environmen-tal distribution of PCDD/Fs and the potential mobilization between dif-ferent environmental media (e.g. food chain transfer) must be known. The primary aim of the work presented in this thesis was to investigate human exposure pathways associated with PCDD/F contaminated sites by combining field measurements and modeling. Site specific field measurements were made at a PCDD/F contaminated site in Sweden and multimedia modeling scenarios were evaluated against site specific data and national reference data. The results show that the congener distributions in exposure media affected by contaminated soil may differ significantly from the distribu-tions found in media from reference locations. Higher chlorinated PCDD/Fs may be transferred into food chains where they contribute to a large fraction of the toxic equivalent concentration (TEQ). Ingestion of locally produced animal food may be an important exposure pathway al-ready at low or moderate PCDD/F soil concentrations. However, the con-gener composition of the source is critical for the exposure. The signifi-cance of the individual exposure routes varies depending on e.g. the spatial distribution and magnitude of the soil contamination, the pro-perties of the exposure media and the human behavior. Multimedia mo-deling can be used in risk assessments as long as model algorithms and model parameters are representative for the superhydrophobic properties of PCDD/Fs. However, selection of physical-chemical PCDD/F properties is a challenge due to large variation in reported values. For some proper-ties, data is scattered or completely lacking
48

Hantering av schaktmassor med hänsyn till miljömålen "giftfri miljö" och "begränsad klimatpåverkan" / Managing excavated soils taking into account the environmental objectives "A Non-Toxic Environment" and "Reduced Climate Impact"

Granbom, Hanna January 2014 (has links)
I Sverige pågick under 2013 efterbehandlingsåtgärder på 1789 förorenade områden. Det nationella miljömålet ”giftfri miljö” har av regeringen angetts som det styrande miljö- målet vid efterbehandling. Efterbehandlingen syftar till att minska risken för förore- ningsspridning i mark från avslutade verksamheter som industrier, vägar med mera. Schaktning av massor utförs vid efterbehandling för att avlägsna förorenade massor från platsen men innebär samtidigt utsläpp av växthusgaser. Både vid schaktning och transport av förorenade massor samt framställande och transport av fyllnadsmaterial används fordon och maskiner som genererar växthusgasutsläpp. Efterbehandlingsarbetet riskerar alltså att ge en negativ påverkan på miljömålet ”begränsad klimatpåverkan”. I denna studie söks svar på frågorna: Kan efterbehandling av förorenade områden bedri- vas med simultan hänsyn till de båda miljömålen ”giftfri miljö” och ”begränsad klimat- påverkan”? och Hur ska ett sådant arbete bedrivas? För att besvara dessa frågor använ- des det webbaserade beräkningsverktyget Carbon footprint från efterbehandling och andra markarbeten från Svenska geotekniska föreningen, SGF, samt en enkätstudie riktad till tillsynsmyndigheter. Beräkningar med verktyget visade att det som främst påverkar växthusgasutsläppen vid efterbehandling är typ av fyllnadsmassor, sammanlagd transportsträcka samt lastkapa- citet hos fordon som transporterar massor. Ingen av de tillfrågade tillsynsmyndigheterna tar hänsyn till växthusgasutsläpp vid godkännande av efterbehandlingsåtgärd. Många ställer sig dock positiva till ett verktyg som ger möjlighet att göra en avvägning mellan miljömål och tror att det skulle underlätta deras arbete. Två strategier som tar större hänsyn till växthusgasutsläpp identifierades. Strategi 1 innebär att sanering sker enligt riktvärdena för känslig eller mindre känslig mark- användning (KM/MKM) och växthusgasutsläppen minimeras genom effektiviserings- åtgärder. Som effektiviseringsåtgärd identifierades bland annat användning av lastbilar med större lastkapacitet och användning av återvunna massor som fyllnadsmaterial. Strategi 2 innebär en avvägning mellan miljömålen ”giftfri miljö” och ”begränsad kli- matpåverkan”. Riktvärdena för KM och MKM kan i strategin överskridas för att mini- mera växthusgasutsläpp. Effektiviseringsåtgärderna från strategi 1 implementeras även i strategi 2. / In Sweden, 1789 contaminated sites were remediated during 2013. The government has stated the national environmental objective “A Non-Toxic Environment” as the gov- erning environmental objective in remediation. The aim of remediation is to reduce the risk of dispersion of contamination in soils from discontinued activities such as indus- tries, roads etc. Excavation of soils takes place to remove contaminated soil from the site. However, it leads to emissions of greenhouse gases. Machines that generate emis- sions of greenhouse gases are needed in excavation, transport of contaminated soils and the production and transport of filling materials. Thus, the environmental objective “Reduced Climate Impact” is likely to be adversely affected by soil remediation. This study was conducted to answer the questions: Can soil remediation be conducted with simultaneous regard to the environmental objectives “A Non-Toxic Environment” and “Reduced Climate Impact”? and How should such efforts be conducted? Two methods were used: the web based calculation tool Carbon footprint from remediation and other soil works from the Swedish Geotechnical Society, SGF, and a survey ad- dressed to regulatory authorities. Calculations with the tool showed that the main impacts on greenhouse gas emissions were choice of filling materials, total transportation distance and carrying load of the vehicles transporting soils. None of the respondent regulatory authorities take green- house gas emissions into account when approving remediation operations. However, many of them displayed positive attitude towards a tool that would make it possible to compare impacts on environmental objectives and stated that such a tool would facili- tate their work. Two strategies that give more consideration to greenhouse gas emissions were identi- fied. In strategy 1, remediation is conducted according to the guidelines of sensitive or less sensitive land use (KM/MKM). The greenhouse gas emissions are minimized through efficiency improvement measures. Use of vehicles with a greater carrying load and recovered soils as filling material are examples of identified efficiency improve- ment measures. Strategy 2 consists of achieving a balance between the environmental objectives “A Non-Toxic Environment” and “Reduced Climate Impact”. In this strat- egy, KM and MKM can be exceeded to minimize greenhouse gas emissions. The effi- ciency improvement measures from strategy 1 can be implemented in strategy 2.
49

Mobilisation et transfert des composés aromatiques polycycliques (HAP et CAP polaires) dans les sols historiquement contaminés par des goudrons de houille : expérimentations au laboratoire et in situ / Polycyclic aromatic compound (PAH and Polar PAC) mobilization and transfer in historically coal tar contaminated soils : Laboratory and in situ experiments

Boulangé, Marine 19 May 2017 (has links)
De nombreux sites pollués par des hydrocarbures aromatiques polycycliques (HAP) sont recensés dans les pays industrialisés. Associés aux 16 HAP US-EPA réglementaires, d’autres composés aromatiques polycycliques (CAP), notamment les CAP polaires (oxygénés et azotés) sont présents. Ils proviennent des mêmes sources que les HAP et peuvent être également formés par des processus biotiques ou abiotiques de transformation des HAP (atténuation naturelle ou procédés de dépollution). Ces CAP, plus polaires que les 16 HAP US EPA, sont plus solubles dans l’eau, induisant potentiellement une mobilité accrue dans les sols et de ce fait un risque pour l’Homme et l’environnement. Il est donc indispensable d’enrichir nos connaissances sur la mobilité des CAP polaires dans les sols et leur transfert vers les eaux souterraines. Ainsi l’objectif de ce projet était d’identifier les mécanismes contrôlant la mobilisation des CAP polaires dans les sols en relation avec les 16 HAP US EPA, et leurs modes de transfert en combinant approches laboratoire et in situ. Nos travaux confirment une mobilisation préférentielle des CAP polaires par rapport aux HAP. La mobilisation dans les sols des CAP polaires ainsi que celle des HAP de faible poids moléculaire est essentiellement pilotée par des processus de dissolution des goudrons (loi de Raoult). Néanmoins, alors que les prédictions de mobilisation des CAP polaires sont satisfaisantes dans le cadre de pollutions « fraiches », un paramètre fondamental doit être pris en compte pour les pollutions historiques ayant subi un effet d’aging : la disponibilité. En effet, quelles que soient les conditions de mobilisation (statique-batch ou dynamique-colonne) la teneur en CAP dans les eaux est fortement dépendante de la disponibilité de la pollution. De plus, pour une forte disponibilité des CAP, les autres paramètres testés (force ionique, température) ont une influence limitée sur la mobilisation alors que pour une faible disponibilité, ils peuvent avoir une influence notable. Par ailleurs, la mobilisation des CAP polaires par les colloïdes semble limitée alors qu’elle est prépondérante pour les HAP de hauts poids moléculaires notamment dans le cas d’une eau présentant une force ionique faible. Les essais réalisés sur une colonne lysimétrique (2 m3) remplie avec une terre de cokerie contaminée au 2/3 supérieure et avec une terre prélevée sur le même site mais non contaminée pour le 1/3 inferieur confirment une mobilisation des CAP selon un mécanisme de dissolution des goudrons avec toutefois des concentrations largement inférieures à celles prédites par la loi de Raoult. Aux différentes échelles expérimentales utilisées (batch, colonnes de laboratoire et lysimétrique), il a été clairement mis en évidence que la composante biologique a une influence très forte. Ainsi, une fois sous forme dissoute, les HAP mais également les CAP polaires sont fortement biodégradés sans que des sous-produits (notamment CAP oxygénés) n’aient pu être détectés / In industrial countries, many sites have been diagnosed polluted by polycyclic aromatic hydrocarbons (PAHs). In addition to the regulated 16 US-EPA PAHs, other polycyclic aromatic compounds (PACs), especially polar PACs (oxygenated and nitrogenated) occur. They come from the same sources as PAHs but they may also be formed due to PAH degradation under biotic or abiotic processes (natural attenuation or remediation treatment). These PACs, more polar than the 16 US-EPA PAHs, are more soluble in water, resulting in a potentially increased mobility in soils and a higher risk for Humans and Environment. Thus, there is a need to increase our knowledge on polar PAC mobility in soils and their transfer to the groundwater. Combining laboratory and in situ works, this project aimed at identifying the mechanisms involved in the release and transfer mode of polar PACs in soils compared to the 16 US-EPA PAHs. Our works confirm a preferential release of polar PACs compared with PAHs. Polar PACs and low molecular weight PAHs (LMW-PAHs) are mainly released according to a coal tar dissolution mechanism (Raoult law). While satisfactory predictions are obtained for polar PAC release when the pollution is “fresh”, availability is a major parameter that needs to be taken into account for historical contamination impacted by aging. Indeed, whatever the leaching conditions (static-batch and dynamic-column), the PAC concentration in water is highly dependent on the availability level of the pollution. In addition, for a high level of PAC availability, the other parameters studied in the project (ionic strength and temperature) have a limited impact on the PAC release whereas at low availability level, these parameters can show a greater influence. Moreover, the PAC release in association with colloids seems limited for polar PACs but dominating for high molecular weight PAHs (HMW-PAHs), especially under low ionic strength conditions. Leaching tests performed on a lysimeter column (2 m3) filled with a contaminated soil in the 2/3 upper part and with a non-contaminated soil in the 1/3 lower part, both soils being sampled on a former coking plant site, confirm a release of PACs according to a coal tar dissolution mechanism although PAC concentrations are widely lower compared to those predicted by the Raoult law. Whatever the experimental scale studied (batch, laboratory or lysimeter column), a clear influence of the biological compartment has been evidenced. Once the PAHs and polar PACs are dissolved into water, they are highly biodegraded. No by-products - especially oxygenated PACs - were detected
50

Revitalização de brownfields : da aplicação do princípio da função socioambiental da propriedade ao gerenciamento de áreas contaminadas ou suspeitas de contaminação

Mattei, Juliana Flávia 19 November 2010 (has links)
Como efeito negativo da sociedade marcada pelo desenvolvimento industrial a qualquer preço, especialmente decorrente do revés processo histórico de desativação de indústrias, surgiram no espaço urbano extensas áreas abandonadas suspeitas ou efetivamente contaminadas. Estas áreas são denominadas brownfields, e podem ser encontradas em praticamente todos os países industrializados ou em processo intenso de industrialização, em qualquer dos Continentes. Mostra-se relevante perceber a situação atual do gerenciamento de brownfields, mais especificamente de áreas contaminadas, que compõem o cenário de grande parte das cidades, e os instrumentos utilizados para promover a sua refuncionalização, especialmente os mecanismos legais criados para este fim. A Região Metropolitana de São Paulo é caso emblemático no Brasil tanto na constatação e registros da formação de brownfields pela relocalização de empreendimentos industriais quanto pela forma pioneira com que vem inovando e implementando instrumentos para a revitalização desses espaços urbanos, aliando iniciativas políticas e legais. Ainda, a recentíssima Resolução CONAMA nº 420, de 28 dezembro de 2009, surge como a primeira regulamentação sobre o tema em nível federal no Brasil, e traz a expectativa de que o tema seja finalmente enfrentado adequadamente no País, embora ainda mereça aprimoramentos e medidas complementares. / Submitted by Marcelo Teixeira (mvteixeira@ucs.br) on 2014-06-04T19:06:59Z No. of bitstreams: 1 Dissertacao Juliana Flavia Mattei.pdf: 1796369 bytes, checksum: 212b89fe86f392c6e12cad7b05d176ea (MD5) / Made available in DSpace on 2014-06-04T19:06:59Z (GMT). No. of bitstreams: 1 Dissertacao Juliana Flavia Mattei.pdf: 1796369 bytes, checksum: 212b89fe86f392c6e12cad7b05d176ea (MD5) / As a negative effect of the industrial development at any price, especially due to the historical process of closure of industries have emerged large urban areas abandoned, which are suspected or actually contaminated. These areas are called brownfields, and can be found in virtually all countries, industrialized or under intense process of industrialization in any of the Continents. It is necessary to study the current status of brownfields management, which have been being a mark of industrialized cities, and the instruments used to promote their revitalization or refunctioning, especially the legal mechanisms created for this purpose. The Metropolitan Region of São Paulo in Brazil is emblematic case both in finding and comfirming the formation of brownfields by relocation of industrial enterprises, as well the pioneer way in innovating and deploying tools for urban areas revitalization, combining political and legal initiatives. Also, the very recent CONAMA Resolution 420 of December 28th, 2009, appears as the first legislation on the issue from federal initiative in Brazil, and raises the hope that the problem is finally addressed adequately in the country, though still worthy of improvements and complementary measures.

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