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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.
191

Sustainability Assessment of a Battery Storage System : Case study of a building-applied photovoltaic system

Flygare, Klara, Frykholm, Selma, Tingstedt, Moa January 2022 (has links)
This bachelor thesis assesses the environmental sustainability of the implementation of a battery storage system in a commercial building. The thesis compares  two case studies, Case 1 being a commercial building with installed solar panels and Case 2 being a commercial building with installed solar panels and a battery storage system. Based on simulations the thesis investigates a battery storage system’s impact on sustainability in terms of CO2 emission equivalents and nuclear wastes. The study is applied in the geographical region of northern Stockholm. The models and calculations are conducted  in MATLAB, Excel and Google Sheets. The effects of the implementation depends on the electricity mix. Implementation of a battery storage system in a commercial building with solar panels, supplied with the Swedish electricity mix, increased the CO2 emissions with 3.6986 ⋅ 103 kg. A majority of the increased emissions was caused by the solar panels. They increased the CO2 emissions with 3.3876 ⋅ 103 kg in Case 1 and 3.6988 ⋅ 103 kg in Case 2. The nuclear waste was reduced with 878.3 g in Case 1 and 959 g in Case 2. The results also showed an increased consumption of renewable energy and a decreased load on the grid due to the implementation of a battery storage. For the sensitivity analysis the Swedish electricity mix was replaced by the European Union electricity mix. The resultant conclusion is that a commercial building decreased its CO2 emissions when solar panels were installed and a battery storage system implemented. The overall conclusion is that the environmental sustainability examination of the implementation resulted in an increasing emission of CO2 and a decreased amount of nuclear waste. Sustainable benefits such as an increased consumption of renewable energy of the building, a reduced dependence on the grid and improved conditions for phasing out nuclear power were also retrieved from the results. On a larger scale it has been made clear that battery storage systems are much needed in the conversion to renewable energy sources, and that research and investment in solar power and storage systems are of utter importance.
192

Natural remediation of surface water systems used as deposits of nuclear industry waste by humic substances. Natural remediation of contaminated surface waters by humic substances

Aleksandrova, Olga 23 October 2009 (has links)
Presented investigation and quantification of natural remediation of highly contaminated surface water systems located in South Ural via humic substances is the first step for sustainable developing of nuclear industry. In the surface water systems, humic substances are shown to promote the immobilization of radionuclides and decreasing of the bioavailability for fish contamination in the investigated water bodies. As proved in this thesis, the influence of humic substances on radionuclide sorption is provided by their special properties of a reversible transform into micelles. The theoretical approach based on consideration of protons as fermion gas in water solution was assumed and applied to this phenomenon, being due to the duel nature of humic substances molecules. The influence of humic substances is quantified as a modified Henry s low of sorption. Investigation of changing of electrostatical status of micelles with increasing of humic substances concentration in water solution leads to modelling of remediation effect of humic substances in respect to influence on fish in contaminated waters. This effect was interpreted and quantified, based on properties of proteins of gill s cell membranes under certain conditions in water solution. Humic substances appreciably influence the chemical and biological interactions between radionuclides and the environment that has experienced increasing interest concerning the remedial uses of humic materials.
193

NMR Spectroscopic Investigation of Lanthanide, Actinide, and Selenium Containing Complexes Related to the Environment or Nuclear Waste Disposals

Kretzschmar, Jerome 27 May 2019 (has links)
The ultimate goal of this work is providing insights into fundamental (physico-) chemical (redox) behavior of hexavalent uranium (U(VI)), trivalent europium (Eu(III)) and selenium (Se), and upon their interaction with ubiquitous small biomolecules (in case of U(VI) and Eu(III)) or alkaline earth metal ions (in case of Se(IV) and Se(VI)) by application of Nuclear Magnetic Resonance (NMR) spectroscopy. NMR spectroscopy is a powerful method proving its usefulness also to environmental and nuclear waste related studies in aqueous solutions by determination of (potential) binding sites, molecular structures (even conformation and configuration) as well as intra- and intermolecular dynamics, (redox) reaction pathways and mechanisms. The present work comprises extensive NMR spectroscopic investigations in aqueous (D2O) solutions on (i) glutathione (GSH) and glutathione disulfide (GSSG) interactions with trivalent lanthanides (Ln(III), particularly Eu(III)) and U(VI), (ii) molecular structures of citrate (Cit) complexes of U(VI), and their reactions upon light-irradiation, as well as (iii) pH- and temperature-dependent speciation of selenium oxyanions, i.e., Se(VI) (selenate) and Se(IV) (selenite and, notably, hydrogen selenite) as well as Se(VI) and Se(IV) interaction with alkaline earth metal ions. These investigations are supported by time-resolved laser-induced fluorescence spectroscopy (TRLFS), ultraviolet-visible-near infrared (UV-Vis-NIR), IR/Raman, and extended X-ray absorption fine structure (EXAFS) spectroscopy, transmission electron microscopy (TEM), as well as quantum chemical calculations on density functional theory (DFT) level. For NMR spectroscopic data on GSH/GSSG complexation towards both Eu(III) and U(VI) are lacking, the herein presented results are new, and nicely complement other spectroscopic studies. Ln(III) complexes of GSH are characterized by their high solubility at least up to 300 mM and pD 5. However, the formation constant of the Eu(III)–GSH 1:1 complex is quite low with log K = 1.71 ± 0.01 as determined by Eu(III)-TRLFS. The diamagnetic La(III) and Lu(III) showed only little effect on the NMR spectra (< 2 ppm) while analogous Eu(III) solutions revealed hyperfine shifts up to 40 ppm. Eu(III)-induced 1H chemical shift changes are solely upfield and attributed to be predominantly due to pseudocontact contribution caused by dipolar interaction. In contrast, Eu(III)-induced 13C chemical shift changes of adjacent atoms – at least for the carboxyl and α-carbons – show alternating signs, indicating spin polarization effects owing to contact contribution. As expected for hard LEWIS acids and shown by other spectroscopies, complexation facilitates by the carboxyl groups. Qualitative differences between the glutamyl and glycyl carboxylate in metal ion complexation are ascribed to COULOMB repulsion due to the positively charged NH3+ in direct vicinity. Investigations of the U(VI)–GSH system covered experiments under both oxidizing and reducing conditions, performed with GSH’s oxidized form, GSSG, at ambient conditions, while samples with reduced GSH were handled under N2 atmosphere. For either condition, U(VI) showed interaction in aqueous (D2O) solution with both GSH and GSSG as determined by U(VI)-induced 1H and 13C chemical shift changes and U(VI) TRLFS, the latter comprising measurements at 25 °C and –120 °C. In principle, the interactions are stronger as compared to the Ln(III) system, and the speciation in both solution and solid is more complex owing to the aqueous chemistry of uranium. Observed binary GSH complexes are [UO2(H2GSH)]2+ for pD values up to ≈ 2.3, and [UO2(HGSH)]+ predominating for pD > 2.3. Complementary to the Eu(III) results, whenever net neutral binary GSH/GSSG or ternary hydroxo GSH/GSSG U(VI) complexes form in solution, both these U(VI) systems revealed extensive precipitation because of the low solubility of these complexes. Binary U(VI) GSSG and ternary U(VI) hydroxo GSSG complexes yield solid phases from pD 2 through 8, even in carbonatic media. The largest quantities of aqueous GSSG–U(VI) complexes are observed for pD ≈ 3.5, with the association constant for pH 3 determined by TRLFS as log K = 4.81 ± 0.08 for a 1:1 complex. GSH cannot compete with hydroxo ligands for complexation as of pD 6, whereas GSSG can at least partially compete with hydroxo and carbonate ligands upon formation of both quaternary U(VI) hydroxo carbonate GSSG, and ternary U(VI) carbonate GSSG (poly-)anionic species of high solubility. Under reducing and near-neutral conditions (pD 6 – 9) GSH immediately reduced U(VI) with subsequent formation of nanocrystalline UO2+x. After centrifugation of the starting material and allowing the decanted supernatant to age, the dissolved nanocrystals assemble network-like as disclosed by TEM, and further analysed by selected-area electron diffraction (SAED), energy-dispersive X-ray (EDX) and UV-Vis spectroscopy, revealing hyper-stoichiometric UO2+x phases. Such network-like assembled actinide containing nanocrystals, with the arrangement most likely provoked by the presence of GSSG, have never been shown before. Complementary, the precipitate that has also been allowed to age as a wet paste, showed color changes from yellow via olive to black, indicating a reaction to proceed. The repeatedly probed and dissolved material exhibited GSSG in NMR spectra, and UV-Vis-NIR absorption bands attributed to U(IV) and, notably, U(V), the latter implying a one-electron transfer with subsequent disproportionation of U(V) to U(IV) and U(VI). Therefore, obtained results advance the understanding of both fundamental redox behavior of uranium and the role of GSH (and related molecules) in U(VI) detoxification processes in vivo. Although investigated for over 70 years, there are still controversial discussions on both speciation and structures of U(VI)–Cit complexes. By means of NMR’s strength in both structure determination and sensitivity to dynamic processes, studies regarding the U(VI)–Cit system allowed further fundamental insights into the structures of the formed complexes on a molecular level. Upon complexation a chiral center is induced in Cit’s central carbon, resulting in the formation of two diastereomeric pairs of enantiomers, whereupon the dimeric complexes exhibit syn and anti configured isomers. In fact, the combination of 17O NMR (note: at natural abundance) and quantum chemical calculations allowed an unambiguous decision on complex geometry and overall configurations. It is evidenced for the first time that the syn isomer is favored in aqueous solution in contrast to the preferably crystallizing anti isomer. Both isomers coexist and interconvert among one another, with a rate estimated to be in the order of 102 s–1 at 25 °C in acidic media, and a corresponding activation energy of approximately 60 kJ mol–1. Moreover, clear indications for uranium chirality is observed for U4+, with the 1:1 U(IV)–Cit complexes also forming two diastereomeric pairs of enantiomers. Comprehensive spectroscopic experiments combined with quantum chemical calculations improved basic understanding of the photo-reaction mechanism in the U(VI)–Cit system. Regardless of sample conditions, Cit is degraded to β-ketoglutarate, acetoacetate, and acetone, while U(VI) was reduced to U(IV) at pD 2 and U(V) at pD 5, suggesting a two- and a one-electron transfer, respectively. NMR signals observed for pD 5 samples at remarkable 1H chemical shift values between 25 and 53 ppm, in combination with UV-Vis-NIR absorptions at about 750 and 930 nm, are assigned to U(V) complexes of citrate. With regard to reported pH dependence on reaction rate and yield in the literature combined with observations in this work, H+/D+ are considered mechanistically crucial constituents. Furthermore, the photoreaction proceeds intermolecularly, requiring for free Cit to be present in solution. In consideration of both the U(VI)–Cit photoreaction and the U(VI)–GSH chemical redox reaction, regardless of the particular mechanism, in both cases the process is intermolecular. This is not only a highly interesting, but the more a very important result, rendering the reductants not required to be bound to U(VI) in order to reduce it. Owing to the suitability of 77Se as NMR-active but non-radioactive Se isotope, this spectroscopy was also applied to study chemical behavior of the nuclear waste related long-lived 79Se. For the first time spectroscopic evidence is given for hydrogen selenite dimerization in aqueous solution upon formation of homo-dimers by hydrogen bonding that are stable up to 60 °C and so are other selenium oxyanionic species. Additionally, a remarkably higher 77Se chemical shift temperature coefficient of the dimer – as compared to corresponding selenite and selenous acid – was found. These findings are attributed to a significant deshielding upon heating due to remarkably different rovibrational modes upon stretching the dimer as a whole instead of its dissociation into monomers owing to the rather strong hydrogen bonds. Interaction of selenium oxyanions with ubiquitous alkaline earth metals, i.e., Ca2+ and Mg2+, showed formation of weak aqueous complexes of both selenite and hydrogen selenite dimer for excessive selenium, however, at high ionic strength (5.6 M) for equimolar Ca2+ and Se(IV) even at pHc 5 crystalline calcium selenite is formed.
194

Evaluation of a concrete plug : From the Dome Plug Experiment DOMPLU at Äspö HRL

Kristiansson, Anders January 2014 (has links)
In SKB’s Äspö Hard Rock Laboratory (HRL) a full scale test of a concrete plug,part of a sealing structure for the depository of spent nuclear fuel, has been carriedout. The aim of this thesis is to evaluate the behavior of the concrete plug and howit corresponds to assumptions made during the design. The concrete plug is domeshaped, un-reinforced and casted in situ with low-pH concrete. It will be exposed tohigh water and swelling pressures and designed for a life span of 100 years. Duringthe first years it shall also prevent water leakage from the inside of the depositiontunnel. Before the pressure is applied, the concrete plug is assumed to de-bond fromthe rock due to autogenous and cooling shrinkage. The gap between the concrete androck is then grouted during cooling and the concrete plug will hence be prestressedwhen the cooling is stopped. The concrete plug is analyzed with the measurement data from the full scale testwith comparisons to results from finite element simulations. The performed measurementsinclude form pressure, internal strain and temperature, concrete plugdisplacements in the tunnel alignment, displacements relative to the rock and ambienttemperatures. Two assumptions have been made during the evaluation; fullbond to the rock or no bond to the rock. The results are also compared to twosimilar experiment that were previously performed. The results indicate that the concrete did de-bond from the rock before grouting tosome extent. It is plausible that a selective de-bonding was obtained. Due to highwater leakage, were cables for the measurement equipment are drawn out from theconcrete plug, the concrete plug was not exposed to the planed maximum pressureload. Results indicate that a water pressure is acting on the concrete plug frominside the rock slot which was not assumed during the design. / I SKB:s Äspölaboratoriet har ett fullskaleförsök på en betongplugg, del av ett pluggsystemför förvaret av kärnavfall, utförts. Syftet med denna uppsats var attutvärdera betongpluggens beteende under fullskaleförsöket och hur det förhållersig till gjorda antaganden under dess utformning. Betongpluggen är kupolformad,oarmerad och platsgjuten med låg-pH-betong. Höga vatten- och svälltryck kommerverka på betongpluggen som är utformad för en livstid på 100 år. Under deförsta åren ska den även motverka läckage från insidan av deponeringstunneln. Innantrycklasten läggs på är det antaget att betongpluggen släpper från berget till följd avautogen krympning och kylning. Utrymmet mellan betongen och berget injekterasoch betongpluggen kommer således vara förspänd efter att kylningen upphört. Betongpluggen är analyserad med mätdata från fullskaleförsöket som jämförts medresultat från finita element analyser. Mätningarna inkluderar formtryck, inre töjningaroch temperaturer, deformationer i tunnelriktningen, deformationer relativt bergetoch lufttemperatur utanför betongpluggen. Två antaganden har gjorts under utvärderingen;att betongen är fast i berget eller att den är fri från berget. Resultaten jämförsäven med två liknande fullskaleförsök som utförts tidigare. Resultaten tyder på att betongpluggen till viss del släppt från berget innan injekteringen.Det är troligt att den släppt på vissa ställen och på andra inte. På grundav för högt vattenläckage där de ingjutna mätinstrumentens kabelgenomföring utförts,kunde inte betongpluggen belastas till det maximala tryck som var planerat.Resultaten tyder på att ett vattentryck verkar på betongpluggen mellan berget ochbetongen vilket inte var antaget under konstruktionen.
195

Swelling, Thermal, and Hydraulic Properties of a Bentonite-Sand Barrier in a Deep Geological Repository for Radioactive Wastes: Effect of Groundwater Chemistry, Temperature and Physical Factors

Alzamel, Mohammed 11 August 2022 (has links)
Electricity generation at nuclear power plants produces a large amount of high-level radioactive waste (HLW) every year, which has long-term detrimental effects on humans and the environment. Other applications of nuclear technology (e.g., medicine, research, nuclear weapons, industry) also produce radioactive waste (e.g., low-level radioactive waste, LLW, Intermediate-level waste, ILW). The potential of deep geological repositories (DGRs) as an option for disposal of radioactive waste (HLW, ILW, LLW) has been examined in several countries, including Bulgaria, Canada, China, Finland, France, Germany, India, Japan, Russia, Spain, Sweden, Switzerland, Ukraine and the United Kingdom and are still under discussion. In Ontario, Canada, DGRs with a multi-barrier system comprised of a sedimentary rock formation (i.e., a natural barrier) and an engineered barrier system (EBS) are currently under consideration. An EBS consists of various components, such as waste containers, buffer, backfill, and tunnel sealing materials, intended to prevent the release of radionuclides. Several engineered barrier materials, including a mixture of bentonite and sand, are currently being considered for use in DGRs for nuclear waste in Ontario. Bentonite has some advantageous physical and chemical properties, such as low permeability, high plasticity, and high swelling potential, which provide it with a good sealing ability and thus make it an effective barrier. However, interaction between the compacted bentonite–sand mixture and underground water chemistry fluids (chemical factor) in the DGR could significantly alter the favourable properties of bentonite (e.g., swelling potential), thus influencing its performance when used in an EBS and eventually jeopardizing the overall safety of DGRs. In addition, other parameters, such as the clay content, initial dry density and moisture content of the compacted barrier (physical factors), as well as the presence of salts in groundwater may affect the physical and physiochemical properties of barrier materials. Moreover, during the lifetime of a DGR for used spent fuel, the bentonite–based barrier material will not only be exposed to a broad range of groundwaters with different chemical compositions, but also to high temperatures (heat generated by the nuclear wastes) (thermal factor). Thus, the interaction between the compacted bentonite–sand mixture, the surrounding groundwater and the heat from the nuclear waste material could jeopardize the favourable properties of the bentonite-based (bentonite-sand) barrier material. Properties of a bentonite-sand barrier is an important characteristic to study while designing and constructing an EBS for a DGR. Thus, to understand and assess the operations of DGRs in Ontario, comprehensive studies must be performed on engineering properties like swelling behaviour, permeability, and thermal conductivity. The goal of this research study is to experimentally investigate the physical, chemical and thermal factors that influencing the engineering properties of a barrier material made up of bentonite-sand composite used in DGRs for nuclear waste in Ontario. Compacted samples are subjected to one-dimensional free swell test to understand the swelling behaviour of the material. Hydraulic conductivity was investigated using a flexible wall permeability test. Thermal conductivity and diffusivity were tested using Decangon KD2 Pro with TR-1 and and KS-1 sensors. The specimens contain different bentonite–sand mixture ratios (20:80, 30:70, 50:50, and 70:30 dry mass), and they are tested under conditions with differing bentonite content, dry density, groundwater chemistry, and temperature. Additional tests were conducted to investigate the microstructure of the specimens. These tests include X-ray diffraction (XRD) analysis, mercury intrusion porosimetry (MIP), and thermogravimetric analyses (TG/DTG). The results reveal that the time and strain required to achieve maximum swelling of compacted bentonite–sand specimens increase with the increase of initial dry density. The simulated saline solutions of Guelph and Trenton groundwater are found to suppress the swelling of the bentonite–sand specimens. This in turn leads to the increase of hydraulic conductivity and decrease of thermal properties of the barrier material. However, the impact of the salinity is significantly reduced by increasing the dry densities and sand content of the compacted material. Moreover, the coupled effect of salinity and temperature decreases the swelling potential of the bentonite-sand mixture. Also, some transformation of Na-montmorillonite into Ca-Montmorillonite was observed. The results also indicate that some montmorillonites might have been transformed into illites, thereby further decreasing the swelling potential of the bentonite-based barrier.
196

Nuclear Waste Canister : Evaluating the mechanical properties of cassette steel after casting

Fager, Fredrick, Chanouian, Serg January 2017 (has links)
Företaget Svensk Kärnbränslehantering AB (SKB) håller på att utveckla en slutförvaringskapsel som kommer innehålla avfall från den svenska kärnkraften. Det är dock fortfarande en process under utveckling och därför undersöks olika typer av metoder och kapselmaterial för att kunna tillverka en hållbar och säker kapsel. Kapseln består av ett hölje av kopparrör med svetsad botten och lock och en insats med stållock. Insatsen är en cylindrisk konstruktion  av segjärn och innehåller en svetsad stålkassett för att skapa utrymmen till det använda kärnbränslet. Insatsen innehåller bland annat stålrör som under tillverkning får utstå en gjutprocess med segjärn och erhåller efter det icke homogena egenskaper. Målet med undersökningen är hur stor påverkan gjutningen har på stålets kemiska sammansättning samt mikrostrukturer. Det som orsakar de inhomogena egenskaperna är främst värmebehandlingen som driver diffusionen av kol från gjutjärnet till stålet, som då ger ett hårdare men sprödare material. Med hjälp av experiment och simuleringar upptäcks hur mycket kol som diffunderar in i stålet samt ändringar i den kemiska sammansättningen i de påverkade zonerna. Identifiering av fasomvandlingar, diffusion och ändringar i mikrostrukturer är stora faktorer som i sin tur ändrar de mekaniska egenskaperna i stålet. / The Swedish Nuclear Fuel and Waste Management Company (SKB) have developed a final storage canister that will contain waste from the Swedish nuclear power plants. However, it is still in a development phase and therefore different types of methods and canister materials are investigated to produce the most durable and safe canister. The canister is made of a copper tube with a welded bottom and lid with an insert. The insert is a cylindrical construction of nodular cast iron that contains a welded steel cassette, to make space for the spent fuel, and a steel lid. The steel tubes showed inhomogeneous properties after being exposed to a casting around them. The aim of this investigation is to clarify the impact of casting on the chemical composition of the steel as well as the microstructure. The cause to the inhomogeneous properties were the diffusion of carbon from the cast iron to the steel, which then produced a harder and more brittle material. Experiments and simulations were used to see the carbon diffusion into the steel as well as what happens with the chemical composition in the affected zones. Identification of phase changes, diffusion and microstructures contributed to changes of mechanical properties in the steel.
197

Effects of Transition Metal Oxide and Mixed-Network Formers on Structure and Properties of Borosilicate Glasses

Lu, Xiaonan 12 1900 (has links)
First, the effect of transition metal oxide (e.g., V2O5, Co2O3, etc.) on the physical properties (e.g., density, glass transition temperature (Tg), optical properties and mechanical properties) and chemical durability of a simplified borosilicate nuclear waste glass was investigated. Adding V2O5 in borosilicate nuclear waste glasses decreases the Tg, while increasing the fracture toughness and chemical durability, which benefit the future formulation of nuclear waste glasses. Second, structural study of ZrO2/SiO2 substitution in silicate/borosilicate glasses was systematically conducted by molecular dynamics (MD) simulation and the quantitative structure-property relationships (QSPR) analysis to correlate structural features with measured properties. Third, for bioactive glass formulation, mixed-network former effect of B2O3 and SiO2 on the structure, as well as the physical properties and bioactivity were studied by both experiments and MD simulation. B2O3/SiO2 substitution of 45S5 and 55S5 bioactive glasses increases the glass network connectivity, correlating well with the reduction of bioactivity tested in vitro. Lastly, the effect of optical dopants on the optimum analytical performance on atom probe tomography (APT) analysis of borosilicate glasses was explored. It was found that optical doping could be an effective way to improve data quality for APT analysis with a green laser assisted system, while laser spot size is found to be critical for optimum performance. The combined experimental and simulation approach adopted in this dissertation led to a deeper understanding of complex borosilicate glass structures and structural origins of various properties.
198

Utmaningar och framtidsmöjligheter för utvecklingen av Svensk Kärnbränslehantering ABs lösning KBS-3 / Challenges and Future Opportunities for the Development of Svensk Kärnbränslehantering AB’s Solution KBS-3

Wallin, Alva, Rosén, Tilda, Harding Olsson, Hjalmi January 2024 (has links)
This study examines the KBS-3 method for nuclear waste management developed by the Swedish Nuclear Fuel Waste Management Company (SKB). This report strives to uncover potential challenges and opportunities for the future development of KBS-3. The study is relevant because the Swedish government is investing in nuclear power where waste must be safely stored to protect the environment from radiation. From a technical perspective, the results indicate a difficult balance between developing the method in line with new research and realising the project. A possible method for the future is reprocessing, but even here the need for KBS-3 would remain as a smaller amount of waste still needs to be stored. Furthermore, from a social perspective, there does not seem to be a clear consensus between researchers and the industry, particularly regarding corrosion risks. Although these discussions can improve the method, there is a risk that they may negatively impact public trust in KBS-3. Similarly, regarding the commercialisation of stakeholder management: it is important that social acceptance is earned through genuine engagement rather than something being sold. From a cost perspective, small improvements are crucial for KBS-3. Saving money within the value chain without compromising safety is vital, but SKB must communicate such changes openly to ensure continued social acceptance. Balancing conflicting goals: technology, social acceptance, and costs seem to reflect a broader societal challenge where different interests often oppose each other. While some may be satisfied with KBS-3 for final disposal even in the future, others may want to continue striving for a solution that does not burden future generations at all. Regardless, KBS-3 can continue to develop as a solution for nuclear waste management in Sweden until a more sustainable method emerges.
199

Extractive Violence on Indigenous Country : sami and Aboriginal Views on Conflicts and Power Relations with Extractive Industries / Extraktivt våld på urfolks marker : konflikter och maktrelationer mellan utvinningsindustrier och urfolk i Sverige och Australien

Sehlin MacNeil, Kristina January 2017 (has links)
Asymmetrical conflicts and power relations between extractive industries and Indigenous groups often have devastating consequences for Indigenous peoples. Many Indigenous groups are struggling to maintain their lands as Indigenous perspectives on connection to Country are frequently undervalued or dismissed in favour of extractivist ideologies. While this conflicted interface has been researched in various parts of the world, studies exploring conflicts and power relations with extractive industries from Indigenous perspectives are few. This thesis is an international comparison aiming to illuminate situations of conflict and asymmetrical power relations caused by extractivism on Indigenous lands from new viewpoints. By drawing on two single case studies, the situations for Laevas reindeer herding Sami community in northern Sweden and Adnyamathanha Traditional Owners in South Australia are compared and contrasted. Yarning (a form of interviewing) is used as a method for data collection and in order to stay as true as possible to the research participants’ own words a number of direct quotes are used. The analysis employs peace researcher Johan Galtung’s concepts of cultural and structural violence as analytical tools to further explore the participants’ experiences of interactions with extractive industries and industrial proponents, including governments. In addition, the thesis introduces the concept of extractive violence as a complement to Galtung’s model. Extractive violence is defined as a form of direct violence against people and/or animals and nature caused by extractivism, which predominantly impacts peoples closely connected to land. The concepts of structural and cultural violence are understood as unjust societal structures and racist and discriminating attitudes respectively. A number of main themes could be identified in the research participants’ narratives. However, the most prominent on both continents was connections to Country and the threat that extractive violence posed to these connections. The results show that although the expressions of cultural, structural and extractive violence experienced by the two Indigenous communities varied, the impacts were strikingly similar. Both communities identified extractive violence, supported by structural and cultural violence, as threats to the continuation of their societies and entire cultures. Furthermore, the results suggest that in order to address violence against Indigenous peoples and achieve conflict transformation, Indigenous and decolonising perspectives should be heard and taken into account. / Konflikter och maktrelationer mellan utvinningsindustrier och urfolksgrupper får ofta förödande konsekvenser för urfolken. På grund av assymetriska maktförhållanden mellan urfolk och majoritetssamhällen som råder på de flesta ställen i världen utsätts många urfolk systematiskt för rättighetskränkningar. Många urfolksgrupper kämpar idag för att bevara sina marker eftersom urfolks perspektiv och kopplingar till marken ofta förminskas eller ignoreras när de står i motsättning till extraktiva ideologier. Även om extraktivism och påverkan på urfolk och urfolksgrupper varit fokus för tidigare studier saknas forskning som utgår från urfolkens perspektiv. Denna avhandling är en internationell jämförelse med syfte att, från nya synvinklar, belysa konfliktsituationer och asymmetriska maktrelationer som orsakats av extraktivism på urfolks marker. Avhandlingen jämför och kontrasterar två fallstudier som utförts med Laevas č earru (sameby) i norra Sverige och Adnyamathanha-folket i delstaten South Australia. I fallstudien som utförts tillsammans med Laevas č earru ingår en grupp av totalt sex forskningsdeltagare, fyra män och två kvinnor. Det var dock framför allt två forskningsdeltagare som intervjuades med anledning av den konfliktsituation mellan Laevas č earru och gruvbolaget LKAB, som står i fokus för artikel I i avhandlingen. I den australiska fallstudien, som utförts tillsammans med Adnyamathanha-folket, ingår en grupp av sju forskningsdeltagare bestående av fyra kvinnor och tre män. Denna studie, artikel II, behandlar Adnyamathanhafolkets kamp mot de australiska och sydaustraliska regeringarnas förslag om att inrätta kärnavfallsdepåer på Adnyamathanhas marker. För att inhämta material användes yarning (en typ av intervjumetod) och för att återge forskningsdeltagarnas ord så rättvisande möjligt inkluderades ett antal direktcitat i texterna. För att möjliggöra en mer djupgående analys av forskningsdeltagarnas upplevelser av konflikter med utvinningsindustrier och förespråkare för extraktivism, inklusive regeringar och stater, användes Johan Galtungs modell, känd som Galtungs våldstriangel, som analysverktyg. Galtungs modell innefattar strukturellt, kulturellt och direkt våld. Direkt våld definieras som fysiskt våld eller hot om fysiskt våld, strukturellt våld utgörs av orättvisa och diskriminerande samhällsstrukturer och kulturellt våld är de attityder som får det strukturella och således även det direkta våldet att te sig legitimt. Föreliggande avhandling introducerar även konceptet extraktivt våld som ett komplement till Galtungs modell där xvi det ersätter direkt våld. Jag definierar extraktivt våld som en typ av direkt våld mot människor och/eller djur och natur orsakat av extraktivism som framför allt påverkar människor med starka kopplingar till sina marker. Extraktivism förstås här som alla typer av aktiviteter som extraherar stora mängder av resurser från marker och människor, exempelvis gruvdrift, skogsbruk, fiske, lantbruk och turism. I forskningsdeltagarnas utsagor identifierades ett antal nyckelteman. Dessa teman uppvisade både likheter och skillnader beroende på deltagarnas olika situationer och förutsättningar. Det mest framträdande temat på båda kontinenterna var dock ”connection to Country” eller kopplingar till marken. Båda grupperna beskrev hur marken och deras förhållande till den innefattade historia, kunskap, traditioner och kultur. För Adnyamathanhagruppen var det mest centrala att rädda och bevara heliga platser som hotas av extraktivism och för Laevas č earru sågs renskötseln och bevarandet av markerna för renarnas skull som det mest väsentliga. Avhandlingens resultat visar att även om de former av kulturellt, strukturellt och extraktivt våld som forskningsdeltagarna upplevde varierade, var effekterna av våldet slående lika. Båda grupperna identifierade extraktivt våld, understött av strukturellt och kulturellt våld, som hot mot fortlevnaden av deras samhällen och kulturer. Resultaten pekar även på vikten av att urfolkens perspektiv inkluderas och blir hörda om konflikttransformering mellan utvinningsindustrier och urfolk ska kunna uppnås.
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Modélisation hydromécanique du comportement des ouvrages souterrains avec un modèle élastoviscoplastique / Hydromechanical modelling of underground excavations with an elastoviscoplastic behaviour law

Plassart, Roland 15 September 2011 (has links)
Le comportement à long terme des excavations souterraines est un enjeu social et économique majeur, en particulier dans le contexte du stockage en formation géologique profonde de déchets nucléaires à Haute Activité et Vie Longue (HAVL). Plusieurs galeries expérimentales ont été creusées dans le laboratoire de recherche souterrain de Meuse/Haute-Marne situé près de Bure en France, où des études sont menées pour comprendre le comportement global de la roche constitutive : l’argilite du Callovo-Oxfordien (COx).L’objectif de cette thèse est d’effectuer une modélisation avec Code_Aster d’ouvrages souterrains, et en particulier d’une des galeries du laboratoire de Meuse/Haute-Marne, en prenant en compte une approche non locale, l’effet du fluage et le couplage hydromécanique dans le cadre de la mécanique des milieux poreux, et de comparer les résultats numériques avec les données expérimentales disponibles.Le modèle élastoviscoplastique spécifiquement utilisé pour cette étude est le modèle L&K : il offre d’une part un couplage entre le comportement instantané et différé, et prend en compte d’autre part la dilatance, paramètre qui gouverne les déformations volumiques du matériau lors d’une sollicitation, et ses fortes variations, caractéristique essentielle des géomatériaux et en particulier du COx. La présence d’un fluide s’écoulant à travers le matériau va ajouter une composante hydraulique à la modélisation, dont le couplage avec la mécanique est assuré par les équations de Biot. Une autre nouveauté de ce travail concerne le couplage entre ce comportement rhéologique complexe et une approche non locale dans un cadre industriel. Parmi les méthodes de régularisation disponibles dans Code_Aster, la méthode second gradient de dilatation a été choisie parce que bien adaptée aux géomatériaux. Son but est de corriger la dépendance au maillage et les solutions numériques localisées.Une fois les outils numériques opérationnels et les paramètres du modèle L&K calés sur des essais effectués en laboratoire sur des échantillons, un bon accord général a été trouvé entre les résultats numériques et les mesures in situ, sans aucun recalage des paramètres. Les effets du temps observés expérimentalement sur l’évolution des déplacements et des pressions d’eau sont retrouvés au sein d’une même modélisation, validant ainsi la démarche prédictive suivie / The long term behaviour of underground excavations is a social and economic stake, in particular in the context of storage in deep geological formation of high activity and long life nuclear waste. Several experimental galleries have been dug in the underground research laboratory (URL) of Meuse/Haute-Marne located close to Bure in France, where studies are leaded in order to understand the global behaviour of the constitutive rock which is the Callovo-Oxfordian (COx) argillite.The purpose of this PhD Thesis is to establish a modelling with Code_Aster of underground excavations, and especially of a Meuse/Haute-Marne laboratory gallery, taking into account non local approach, creep effect and hydromechanical coupling in the framework of the mechanics of porous media, and then to compare numerical results with available experimental data.The specific elastoviscoplastic model used in this study is the L&K model: it offers a coupling between instantaneous and delayed behaviour, and it takes into account the dilation, parameter which governs the volume strains of the material during a solicitation, and its strong variation, a specificity of geomaterials and so of COx argillite. The fluid flowing through the material adds a hydraulic component to the modelling, which is coupled to mechanic component thanks to Biot’s equations.Another novelty of this work concerns the coupling between such complex rheological behaviour and a non local approach in an industrial way. Among methods of regularization available in Code_Aster, the second gradient of dilation is well fitted to geomaterials. Its aim is to correct mesh dependency and numerical localized solutions.After describing numeric tools and setting parameters of the L&K model on laboratory tests, a good general agreement was found between numeric results and in situ measures, without resetting parameters. Time effects experimentally measured on displacement and pore pressure evolution are observed in the same modelling, validating the followed predictive approach

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