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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

Field Trial of Dolomitic Limestone as an In Situ Soil Remediation Technique to Reduce Nickel Toxicity in Soybean and Oat

Cioccio, Stephen Christopher 14 September 2012 (has links)
As more contaminated sites are being discovered, new in situ remediation techniques need to be developed. Chemically treating soil with lime to increase soil pH is a method that may decrease the bioavailability of the contaminant. To test the usefulness of rendering metal-contaminated soils alkaline with dolomitic lime, to improve crop performance, field trials at a site in Port Colborne, ON, with soil nickel concentration (as high as 5000 mg/kg) from refinery emissions were completed. Oat and soybean yield, as well as plant uptake and bioavailabilty of nickel in soil were evaluated. Liming Ni-contaminated soils decreased soybean foliar Ni concentrations from 36.68 µg/g in unlimed fields to 19.98 µg/g in 50 t/ha limed fields in the 2007 growing season; yield of both oat and soybean in unlimed soils was the same (p>0.05) as at a reference site, suggesting that for these soils, remediation is not necessary for yield.
2

Tratabilidade de solos tropicais contaminados por resíduos da indústria de revestimentos cerâmicos. / Treatability of tropical soils contaminated by solid wastes from ceramics covergin industry.

Oliveira, Luciana Pena de 17 October 2006 (has links)
O Pólo Cerâmico de Santa Gertrudes, localizado na região de Rio Claro, no Estado de São Paulo, é o maior do gênero no país, contando com mais de 40 unidades industriais do setor de pisos e revestimentos e responsável por mais da metade da produção nacional. A área de estudos, denominada Região dos Lagos de Santa Gertrudes, situa-se na bacia hidrográfica do Córrego da Fazenda Itaqui, sub-afluente do Rio Corumbataí, manancial utilizado para o abastecimento público de aproximadamente 650 mil habitantes. Os lagos não são formações naturais, mas resultantes da inundação de antigas cavas de extração de argila, pelo afloramento do aqüífero da Formação Corumbataí. Nessas cavas, foram depositados resíduos da linha de esmaltação e lançados efluentes líquidos do processo produtivo das cerâmicas, contendo elevadas concentrações de metais, principalmente de boro (B), cádmio (Cd), chumbo (Pb) e zinco (Zn). Este trabalho de pesquisa buscou oferecer uma alternativa de remediação do solo contaminado, por meio do estudo de três processos de lixiviação de metais, produzida pela lavagem com ácido sulfúrico concentrado e por soluções de peróxido de hidrogênio a 30% e de ácido clorídrico 0,1 M. Os resultados obtidos identificaram que a lavagem com ácido sulfúrico concentrado promoveu a redução de 50% dos teores de Zn e a lavagem com a solução de ácido clorídrico 0,1 M reduziu os teores de Pb e Zn em 15% e 10%, respectivamente. O teor remanescente de Zn no solo tratado com ácido sulfúrico concentrado foi de 117 mg/kg e os teores de Pb e Zn remanescentes no solo tratado com a solução de ácido clorídrico 0,1 M foram de 806 mgPb/kg e 213 mgZn/kg, valores estes inferiores aos de intervenção estabelecidos pelo órgão de controle ambiental paulista. / The Ceramic Pole of Santa Gertrudes, located in the region of Rio Claro, in the State of São Paulo, is the largest of the gender in the country, counting with more than 40 industrial units of the section of floors and coverings and responsible for more of the half of the national production. The area of studies, denominated Region of the Lakes of Santa Gertrudes, locates at the Córrego da Fazenda Itaqui river basin, sub-affluent of the River Corumbataí, spring used for the public provisioning of approximately 650 thousand inhabitants. The lakes are not natural formations, but resultants of the flood of old diggings of clay extraction, for the blooming of Formation Corumbatai?s aquifer. In these diggings were deposited solid wastes from the line of enamels and thrown liquid effluents of the productive process of the ceramic, containing high concentrations of metals, mainly of boron (B), cadmium (Cd), lead (Pb) e zinc (Zn). This research work aimed to offer an alternative of remediation of the polluted soil, through the study of three leaching processes of metals, produced by washing of soil with concentrated sulfuric acid and solutions of hydrogen peroxide 30% and 0,1 M hydrochloric acid. The obtained results identified that the washing with concentrated sulphuric acid caused a 50% reduction of Zn contents and the washing with 0,1M hydrochloric acid solution reduced Pb and Zn contents in 15% and 10%, respectively. The Zn contents remaining in the soil processed with concentrated sulphuric acid were 117 mg/kg and the Pb and Zn contents remaining in the soil processed with 0,1M hydrochloric acid solution were 806 mgPb/kg and 213 mgZn/kg, values which are lower than the intervention values established by São Paulo?s environmental control agency.
3

Tratabilidade de solos tropicais contaminados por resíduos da indústria de revestimentos cerâmicos. / Treatability of tropical soils contaminated by solid wastes from ceramics covergin industry.

Luciana Pena de Oliveira 17 October 2006 (has links)
O Pólo Cerâmico de Santa Gertrudes, localizado na região de Rio Claro, no Estado de São Paulo, é o maior do gênero no país, contando com mais de 40 unidades industriais do setor de pisos e revestimentos e responsável por mais da metade da produção nacional. A área de estudos, denominada Região dos Lagos de Santa Gertrudes, situa-se na bacia hidrográfica do Córrego da Fazenda Itaqui, sub-afluente do Rio Corumbataí, manancial utilizado para o abastecimento público de aproximadamente 650 mil habitantes. Os lagos não são formações naturais, mas resultantes da inundação de antigas cavas de extração de argila, pelo afloramento do aqüífero da Formação Corumbataí. Nessas cavas, foram depositados resíduos da linha de esmaltação e lançados efluentes líquidos do processo produtivo das cerâmicas, contendo elevadas concentrações de metais, principalmente de boro (B), cádmio (Cd), chumbo (Pb) e zinco (Zn). Este trabalho de pesquisa buscou oferecer uma alternativa de remediação do solo contaminado, por meio do estudo de três processos de lixiviação de metais, produzida pela lavagem com ácido sulfúrico concentrado e por soluções de peróxido de hidrogênio a 30% e de ácido clorídrico 0,1 M. Os resultados obtidos identificaram que a lavagem com ácido sulfúrico concentrado promoveu a redução de 50% dos teores de Zn e a lavagem com a solução de ácido clorídrico 0,1 M reduziu os teores de Pb e Zn em 15% e 10%, respectivamente. O teor remanescente de Zn no solo tratado com ácido sulfúrico concentrado foi de 117 mg/kg e os teores de Pb e Zn remanescentes no solo tratado com a solução de ácido clorídrico 0,1 M foram de 806 mgPb/kg e 213 mgZn/kg, valores estes inferiores aos de intervenção estabelecidos pelo órgão de controle ambiental paulista. / The Ceramic Pole of Santa Gertrudes, located in the region of Rio Claro, in the State of São Paulo, is the largest of the gender in the country, counting with more than 40 industrial units of the section of floors and coverings and responsible for more of the half of the national production. The area of studies, denominated Region of the Lakes of Santa Gertrudes, locates at the Córrego da Fazenda Itaqui river basin, sub-affluent of the River Corumbataí, spring used for the public provisioning of approximately 650 thousand inhabitants. The lakes are not natural formations, but resultants of the flood of old diggings of clay extraction, for the blooming of Formation Corumbatai?s aquifer. In these diggings were deposited solid wastes from the line of enamels and thrown liquid effluents of the productive process of the ceramic, containing high concentrations of metals, mainly of boron (B), cadmium (Cd), lead (Pb) e zinc (Zn). This research work aimed to offer an alternative of remediation of the polluted soil, through the study of three leaching processes of metals, produced by washing of soil with concentrated sulfuric acid and solutions of hydrogen peroxide 30% and 0,1 M hydrochloric acid. The obtained results identified that the washing with concentrated sulphuric acid caused a 50% reduction of Zn contents and the washing with 0,1M hydrochloric acid solution reduced Pb and Zn contents in 15% and 10%, respectively. The Zn contents remaining in the soil processed with concentrated sulphuric acid were 117 mg/kg and the Pb and Zn contents remaining in the soil processed with 0,1M hydrochloric acid solution were 806 mgPb/kg and 213 mgZn/kg, values which are lower than the intervention values established by São Paulo?s environmental control agency.
4

Sustainable phosphorus removal in onsite wastewater treatment

Eveborn, David January 2013 (has links)
Aquatic eutrophication is a serious environmental problem that occurs all over the world. To protect surface waters (in particular the Baltic Sea), the regulatory pressure on onsite wastewater treatment (OWT) systems have increased in Sweden. Stringent requirements have led to uncertainties regarding the capability of conventional treatment techniques (soil treatment systems (STS)) to remove phosphorus (P), but they have also stimulated the development and introduction of enhanced P treatment techniques. In this thesis the accumulation and mobility of P as well as the chemical P removal mechanisms were studied in soils and reactive filter media. This knowledge was then used in environmental systems analysis. A model based on life cycle assessment (LCA) methodology was developed to evaluate the overall environmental performance of conventional and enhanced P treatment systems under various local conditions. The P accumulation in the studied STS varied (320-870 g m-3) and the accumulated P was rather mobile in some soils. Phosphorus compounds were identified in alkaline reactive filter media (calcium phosphates predominated) by means of X-ray Absorption Near Edge Structure (XANES). In sandy soils from STS aluminium was found to be a key element for P removal, as evidenced by a strong relationship between oxalate-extractable P and Al. The LCA studies indicated that enhanced P treatment systems may be beneficial from an eutrophication and P recycling perspective but causes increased impacts in terms of global warming and acidification. Despite the drawbacks, enhanced P treatment techniques should be considered suitable substitutes to surface water discharge STS under most conditions. This is because the latter systems have such a strong eutrophication impact. On the other hand, under appropriate conditions, STS with groundwater discharge may be advantageous. These systems generally caused low environmental impacts except for the dispersion of P resources. / <p>QC 20130419</p>
5

Regeneration methods to reduce pine weevil damage to conifer seedlings /

Petersson, Magnus, January 2004 (has links) (PDF)
Diss. (sammanfattning). Uppsala : Sveriges lantbruksuniversitet, 2004. / Härtill 4 uppsatser.
6

Amélioration hydro-mécanique d'une couverture de centre de surface de stockage de déchets radioactifs FA et MA à vie courte / Hydro-mechanical improvement of the cap cover of a surface landfill for low and intermediate level radioactive waste short life time

Verstaevel, Matthieu 29 June 2015 (has links)
La présente étude concerne le Centre de Stockage de la Manche (CSM), ce centre dédié aux déchets faiblement etmoyennement actifs à vie courte l’un des sites précurseurs au niveau international. La recherche proposée dans lecadre de la présente thèse CIFRE se concentre sur l’étude hydraulique des matériaux de couverture du site, et surleur amélioration hydromécanique. Il s’agit donc de renforcer leur imperméabilité afin que cette couche puisse jouerun rôle de barrière minérale. Une contrainte imposée par l’Andra était de considérer la validité du réemploi dumatériau en place au moyen d’un traitement par adjuvant. Ce matériau est un limon sableux, donc un matériaucomportant déjà une part de fines non négligeable. S’il existe dans la littérature de nombreuses études surl’amélioration mécanique des matériaux fins (applications aux infrastructures routières) et sur le traitement dematériaux pulvérulents par ajout d’une fraction fine (constitution de barrières étanches), il existe très peu d’études surle renforcement de l’imperméabilité de sols fins. Une campagne d’essais physiques sur les matériaux traités à labentonite a été réalisée à différents taux de traitement. Les résultats ont montré que l’ajout d’adjuvant entraine unediminution de leur poids volumique sec optimum pour une énergie de compactage Proctor normal et uneaugmentation de leur teneur en eau optimum. En complément, la sensibilité à l’érosion, interne ou externe, observéependant les essais à l’oedoperméamètre, a été vérifiée à partir de différents critères de stabilité disponibles dans lalittérature. A la différence du traitement d’un sol pour remblais routiers, on ne recherche pas une résistancemécanique accrue mais une flexibilité du matériau. On observe effectivement que le traitement n’augmente pas larigidité du matériau. La conductivité hydraulique des matériaux non traités et traités a été mesurée. Cette étude a étémenée à partir de plusieurs dispositifs (oedoperméamètre, perméamètres à parois rigides et à parois souples).L’influence du taux de traitement du matériau sur la diminution de la conductivité hydraulique a pu être observée.Quatre planches d’essais instrumentées ont été réalisées, elles devraient rester en fonction plusieurs années. Lesmesures de conductivité hydraulique initiales sur les planches d’essais ont montré que les résultats étaientconformes à ceux obtenus au laboratoire. Ces planches d’essais, permettront de suivre l’évolution éventuelle desperformances du traitement. La poursuite de leur suivi apparait être cruciale pour la validation du traitement avant samise en oeuvre à grande échelle sur toute la couverture du CSM. / This study related to the Manche storage center (CSM), one of the first landfill in the world dedicated to low andintermediate radioactive waste short-live time. The researches considered in this thesis supported by industrialcompanies, focus on the hydraulic study of cap cover materials of the site, and their hydromechanical improvement.The aim is to improve their impermeability in order to be substituted to the geomembrane as cap cover liner. Aspecification imposed by Andra was to consider a solution of the re-use of the in situ material by adding of additive.The initial material is a sandy silt, a material with a significant proportion of fines. In the literature there are manystudies on the mechanical improvement of fine materials (applications to road infrastructure) and the treatment ofsandy materials by adding a fine fraction (constitution of waterproof barriers). On the other hand there are very fewstudies on the impermeability improvement of fine soils. A physical tests campaign on treated materials withbentonite was carried out at various treatment rates. The results showed that the addition of additive induces adecrease in optimum dry unit weight for a normal Proctor compaction energy and increases their optimum watercontent. In addition, the susceptibility to erosion, internal or external, observed during oedopermeameter test wasassessed from various stability criteria available in the literature. Unlike the treatment of soil for road embankments,the increase of the material stiffness is not wanted and flexibility is preferred what is observed with the treatmenttested. The comparative hydraulic conductivity of the untreated and treated materials were measured. In this studydifferent devices (oedopermeametere, permeameters, triaxials device) were used. The influence of the treatment rateof the material on the decrease of the hydraulic conductivity was observed. Four large scale experimentations weredesigned; they should be monitored for several years. The initial hydraulic conductivity measurements on siteshowed that the results were compatible with those obtained in the laboratory tests. These large scaleexperimentations will demonstrate the possible evolution of the material improvement. The monitoring of this siteexperimentation is a preliminary test require before the application of the selected treatment on the cap cover of theCSM.
7

Estudo de algumas soluções de tratamento de solos moles para construção de aterros no Trecho Sul do Rodoanel - SP. / Study of a new solutions of treatment of soft soil for the construction of earthfill in the South Stretch of Rodoanel Highway.

Nogueira, Estela Grassi 09 August 2010 (has links)
A construção do Rodoanel Trecho Sul movimentou o meio geotécnico, gerando novas informações sobre os solos locais e apresentando novas tecnologias construtivas, já disponíveis em outros mercados, mas pouco ou não utilizadas nas obras brasileiras. Estas novas técnicas de melhoria dos solos prometem solucionar problemas importantes, como a deformabilidade e resistência de uma camada de argila mole depositada na fundação de um aterro, por meios simples, rápidos, econômicos e ambientalmente interessantes. Este trabalho apresenta os problemas de engenharia geotécnica enfrentados durante a implantação deste empreendimento, na região próxima à Represa Billings e da Interseção Imigrantes, e destaca as soluções geotécnicas executadas para estabilizar a fundação dos aterros compactados construídos nesta região, caracterizada pela ocorrência de solos orgânicos muito moles. Destas soluções enfatizam-se neste estudo os tratamentos de solos moles identificados como Consolidação Profunda Radial (CPR) e a Mistura Mecânica de Aglomerante Cimentício com os solos moles saturados locais. O desempenho final destas tecnologias, em relação ao ganho de resistência e o aumento de compressibilidade adquiridos pela camada tratada, foram avaliados através dos ensaios de campo e da instrumentação implantada na área de interesse. / The construction of the South Stretch of Rodoanel Highway created a commotion in the geotechnical segment, generating new information about the local soils and presenting new construction technology, already available in other markets, but still with very limited or even no use in the Brazilian works. This new techniques of soil improvements, promises to solve important issues, like deformability and resistance of a soft clay layer located at the foundation of an embankment, by means that can be qualified as simple, fast, economical and environmentally interesting. This document presents the geotechnical engineering issues encountered during the implantation of this entrepreneur, at the region near Billings Reservoir and at the intersection with Imigrantes Highway, and points out the geotechnical solutions used to stabilize the foundation of compacted earth fill builted at this region, that is characterized by the occurrence of very soft organic soils. This study emphasizes in the solutions of treatment of soft soil identified as Deep Radial Consolidation (CPR) and the Mechanical Mixture of Cimentitius Binder with the local saturated soft soils. The final performance of this technologies, consearning the gain of resistance and the reduction of deformability, acquired by the treated layer, were evaluated through field tests and by the instrumentation placed at the area of interest.
8

Estudo de algumas soluções de tratamento de solos moles para construção de aterros no Trecho Sul do Rodoanel - SP. / Study of a new solutions of treatment of soft soil for the construction of earthfill in the South Stretch of Rodoanel Highway.

Estela Grassi Nogueira 09 August 2010 (has links)
A construção do Rodoanel Trecho Sul movimentou o meio geotécnico, gerando novas informações sobre os solos locais e apresentando novas tecnologias construtivas, já disponíveis em outros mercados, mas pouco ou não utilizadas nas obras brasileiras. Estas novas técnicas de melhoria dos solos prometem solucionar problemas importantes, como a deformabilidade e resistência de uma camada de argila mole depositada na fundação de um aterro, por meios simples, rápidos, econômicos e ambientalmente interessantes. Este trabalho apresenta os problemas de engenharia geotécnica enfrentados durante a implantação deste empreendimento, na região próxima à Represa Billings e da Interseção Imigrantes, e destaca as soluções geotécnicas executadas para estabilizar a fundação dos aterros compactados construídos nesta região, caracterizada pela ocorrência de solos orgânicos muito moles. Destas soluções enfatizam-se neste estudo os tratamentos de solos moles identificados como Consolidação Profunda Radial (CPR) e a Mistura Mecânica de Aglomerante Cimentício com os solos moles saturados locais. O desempenho final destas tecnologias, em relação ao ganho de resistência e o aumento de compressibilidade adquiridos pela camada tratada, foram avaliados através dos ensaios de campo e da instrumentação implantada na área de interesse. / The construction of the South Stretch of Rodoanel Highway created a commotion in the geotechnical segment, generating new information about the local soils and presenting new construction technology, already available in other markets, but still with very limited or even no use in the Brazilian works. This new techniques of soil improvements, promises to solve important issues, like deformability and resistance of a soft clay layer located at the foundation of an embankment, by means that can be qualified as simple, fast, economical and environmentally interesting. This document presents the geotechnical engineering issues encountered during the implantation of this entrepreneur, at the region near Billings Reservoir and at the intersection with Imigrantes Highway, and points out the geotechnical solutions used to stabilize the foundation of compacted earth fill builted at this region, that is characterized by the occurrence of very soft organic soils. This study emphasizes in the solutions of treatment of soft soil identified as Deep Radial Consolidation (CPR) and the Mechanical Mixture of Cimentitius Binder with the local saturated soft soils. The final performance of this technologies, consearning the gain of resistance and the reduction of deformability, acquired by the treated layer, were evaluated through field tests and by the instrumentation placed at the area of interest.
9

Tausojanti cukrinių runkelių auginimo technologija / Protective growth technology of sugar- beets

Prelgauskaitė, Asta 07 June 2005 (has links)
There are presented the following parts in the final master diploma work: introduction, 4 chapters, conclusions and list of literature. Total coverage of diploma work- 57 pages, including 41 pictures and 6 charts. There are presented 51 sources of information. The goal of diploma work- to analyze traditional and protective technology of growth of sugar- beets and machines of soil treatment. To construe the movement of knifes of rotor cultivator in the soil. To investigate and compare sowing, harvest and qualitative indexes of growing the sugar- beets according different technologies. Main tasks of diploma work- to analyze technologies of growth of sugar beets; to overlook machines of soil treatment and their technological processes; to analyze the movement of vertical rotor cultivators and cultivators with horizontal roller in the soil; to investigate the influence of different technologies of soil treatment and sowing to quality of insertion of seeds of sugar- beets and to harvest of sugar beets and it’s qualitative indexes; to evaluate and to compare treatment of soil and sowing technologies of sugar beets by indexes of energy.
10

Revegetation of coal mine dumps to ameliorate effects of acidic seepage.

Mikli, Markus H. January 2001 (has links)
Species prescriptions are developed for revegetating abandoned acidic coal overburden seepage sites in the Collie region of Western Australia. The research involved selecting appropriate plant species and determining successful methods of enhancing revegetation. Candidate species were screened for tolerance to acidic overburden materials, local climate conditions and metal toxicity. Methods tested included improving spoil conditions and trialing an alternative method for seeding.Twelve species of native plants were tested for tolerance in two acid overburden materials in pot and field trials. Eucalyptus robusta is the most tolerant, Eucalyptus camaldulensis and Eucalyptus cladocalyx are highly tolerant, Eucalyptus rudis and Melaleuca hamulosa demonstrate potential, provided adequate soil moisture is available.An important growth restriction factor in acid soils is the presence of free aluminium ions. A glasshouse trial performed on seven species for tolerance to aluminium toxicity revealed E. robusta as most tolerant and E. camaldulensis and Kunzea ericifolia a highly tolerant. E. rudis and M. hamulosa are moderately tolerant, but E. cladocalyx and Eucalyptus diversicolor are very sensitive to aluminium.Various methods were trialed to increase growth of seedlings transplanted on to acidic overburden sites. Both commercial cow manure and slow-release fertiliser tablets increase growth, whereas commercial potting mix and lime do not. Inoculation of plants with the ectomycorrhiza fungus Pisolithus tinctorius increases the amount of infection in roots but does not enhance plant growth.Supplementary fertilisation is necessary to maintain growth (nitrogen) and restore chlorophyll production (phosphorus) in fast growing eucalypt seedlings planted into typical acidic spoils. Poor levels of nutrient availability in such acidic sites appear to be the primary factor in ++ / retarding growth. In the absence of supplementation, foliage reddening is observed in several species.An alternative method of seeding dumps is fascining. Prepared dump surfaces may be covered with capsule-laden branchwood of myrtaceous species. Material of the locally available Kunzea ericifolia is effective in producing many seedlings. Subsequent seedling growth is enhanced with fertiliser and lime addition.

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