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Heat transfer in the storage cask and its impact on the environment
Marcell, Jan ; Slovák, Jiří (referee) ; Matal, Oldřich (advisor)
The main object of this diploma thesis is solving problems concerning heat transfer in disposal cannister for spent nuclear fuel. In forepart possibilities of conceptual solving according of disposal cannister to particular states are reviwed. On the basis of this a variant of possible protect of a nuclear fuel repository in the Czech republic has been chosen for calculationof a simplified model. Second part is computational solving that was divided into two parts. The first deals with calculation of heat transfer in disposal canister and is done by an analytical method. In the second part is calculation is done by numerical model. In this way region in near surroundings of this model of disposal cannister is analysed. Last part those diploma thesis deals with design of the storage of spacing among disposal canisters as well as optimum placing in underground part of nuclear fuel repository.
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Present and Future Management and Utilization of Spent Nuclear Fuel
Hruškovič, Jan ; Mičian, Peter (referee) ; Katovský, Karel (advisor)
The Bachelor Thesis deals with spent nuclear fuel and possibilities of its management and utilization. The first chapter is focused on theoretical introduction, the nuclear fuel cycle is explained there together with radioactive waste and spent nuclear fuel. Possibilities of its management and utilization are listed, including some examples of practice around the world. The second chapter is focused on spent nuclear fuel in the Czech Republic. The reader is briefly acquainted with the history and present of nuclear energy in Czech Republic. Then the plan for the construction of a deep repository is described, including some requirements and criteria that need to be met and taken into account in planning and construction. The last chapter focuses on the attitude of countries that are significant in terms of nuclear energy to the management of spent nuclear fuel, including their brief introduction.
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The influence of temperature and hydration on the long term stability of the buffer material
Švandová, Jana ; Přikryl, Richard (advisor) ; Galamboš, Michal (referee) ; Havlová, Václava (referee)
The influence of temperature and hydration on the long term stability of the buffer material was studied during two experimental studies - "Mock-Up-CZ" experiment and "Long-term stability of engineering barriers" project. The objectives of these studies is to identify mineralogical, chemical and geochemical changes and describe transformation processes in the bentonite materials due to heating and interaction with various saturation media (with different chemical composition) under controlled laboratory and in situ conditions. The Rokle bentonite suitability for its use in the Czech deep repository of high-level radioactive waste was investigated. Mineralogical changes in the bentonites were evaluated by X-ray diffraction. The material of the barrier of the Mock-Up-CZ experiment is a mixture of nonactivated Rokle bentonite (85 vol.%), quartz sand (10 vol.%) and graphite (5 vol.%). The barrier has been subjected to thermal stress (up to 90 řC) and synthetic granitic water for 45 months. No sample from 70 analysed samples taken at different depth levels and distances from the source of the heat and/or water showed measurable transformation of original smectites. Newly formed gypsum bordered by illite aureole was detected in the upper part of the experimental set-up (backfill samples), i.e. in the...
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The influence of temperature and hydration on the long term stability of the buffer material
Švandová, Jana
The influence of temperature and hydration on the long term stability of the buffer material was studied during two experimental studies - "Mock-Up-CZ" experiment and "Long-term stability of engineering barriers" project. The objectives of these studies is to identify mineralogical, chemical and geochemical changes and describe transformation processes in the bentonite materials due to heating and interaction with various saturation media (with different chemical composition) under controlled laboratory and in situ conditions. The Rokle bentonite suitability for its use in the Czech deep repository of high-level radioactive waste was investigated. Mineralogical changes in the bentonites were evaluated by X-ray diffraction. The material of the barrier of the Mock-Up-CZ experiment is a mixture of nonactivated Rokle bentonite (85 vol.%), quartz sand (10 vol.%) and graphite (5 vol.%). The barrier has been subjected to thermal stress (up to 90 řC) and synthetic granitic water for 45 months. No sample from 70 analysed samples taken at different depth levels and distances from the source of the heat and/or water showed measurable transformation of original smectites. Newly formed gypsum bordered by illite aureole was detected in the upper part of the experimental set-up (backfill samples), i.e. in the...
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Present and Future Management and Utilization of Spent Nuclear Fuel
Hruškovič, Jan ; Mičian, Peter (referee) ; Katovský, Karel (advisor)
The Bachelor Thesis deals with spent nuclear fuel and possibilities of its management and utilization. The first chapter is focused on theoretical introduction, the nuclear fuel cycle is explained there together with radioactive waste and spent nuclear fuel. Possibilities of its management and utilization are listed, including some examples of practice around the world. The second chapter is focused on spent nuclear fuel in the Czech Republic. The reader is briefly acquainted with the history and present of nuclear energy in Czech Republic. Then the plan for the construction of a deep repository is described, including some requirements and criteria that need to be met and taken into account in planning and construction. The last chapter focuses on the attitude of countries that are significant in terms of nuclear energy to the management of spent nuclear fuel, including their brief introduction.
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Properties of cementitious matrix in the environment of radioactive waste respositories
Podojil, Adam ; Jelínek, Emil (advisor) ; Kozlovcev, Petr (referee)
Cementitious materials will serve as a construction and filler material for the construction of a deep repository of radioactive waste. Therefore, three different materials represented by four samples were studied in the present work. This is CEM II AS 42,5R cement commercially available in Čížkovice, cement CEM III B / 32,5 SV with ash and aggregate used as filler concrete for storage chambers from radioactive waste repository Richard and cement CEM I 42, 5 with fine and coarseraggregate used for fixed radioactive waste (RAW) in Velké Zbytky in the area of ÚJV Řež,as Chemical (silicate analysis) and phase composition (XRD powder diffraction analysis) were determined in the studied materials. Further, the orientation strength of the monolithic samples and their mutual comparison (compression strength measurement) were determined. Percolation leaching experiments were carried out, three columns with CEMII, RICHARD and ÚJV samples were run. The conditions of the experiments were chosen to approach the conditions in the rock environment of a possible deep radioactive waste repository. Synthetic granite water (SGW) was used as the leaching solution. In all column experiments, attempts to observe changesin the concentrations of selectedindicators (Na+ , K+ , OH- ,Ca2+ ,pH, Conductivity, SiO2, Mg2+ and...
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The influence of temperature and hydration on the long term stability of the buffer material
Švandová, Jana
The influence of temperature and hydration on the long term stability of the buffer material was studied during two experimental studies - "Mock-Up-CZ" experiment and "Long-term stability of engineering barriers" project. The objectives of these studies is to identify mineralogical, chemical and geochemical changes and describe transformation processes in the bentonite materials due to heating and interaction with various saturation media (with different chemical composition) under controlled laboratory and in situ conditions. The Rokle bentonite suitability for its use in the Czech deep repository of high-level radioactive waste was investigated. Mineralogical changes in the bentonites were evaluated by X-ray diffraction. The material of the barrier of the Mock-Up-CZ experiment is a mixture of nonactivated Rokle bentonite (85 vol.%), quartz sand (10 vol.%) and graphite (5 vol.%). The barrier has been subjected to thermal stress (up to 90 řC) and synthetic granitic water for 45 months. No sample from 70 analysed samples taken at different depth levels and distances from the source of the heat and/or water showed measurable transformation of original smectites. Newly formed gypsum bordered by illite aureole was detected in the upper part of the experimental set-up (backfill samples), i.e. in the...
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The influence of temperature and hydration on the long term stability of the buffer material
Švandová, Jana ; Přikryl, Richard (advisor) ; Galamboš, Michal (referee) ; Havlová, Václava (referee)
The influence of temperature and hydration on the long term stability of the buffer material was studied during two experimental studies - "Mock-Up-CZ" experiment and "Long-term stability of engineering barriers" project. The objectives of these studies is to identify mineralogical, chemical and geochemical changes and describe transformation processes in the bentonite materials due to heating and interaction with various saturation media (with different chemical composition) under controlled laboratory and in situ conditions. The Rokle bentonite suitability for its use in the Czech deep repository of high-level radioactive waste was investigated. Mineralogical changes in the bentonites were evaluated by X-ray diffraction. The material of the barrier of the Mock-Up-CZ experiment is a mixture of nonactivated Rokle bentonite (85 vol.%), quartz sand (10 vol.%) and graphite (5 vol.%). The barrier has been subjected to thermal stress (up to 90 řC) and synthetic granitic water for 45 months. No sample from 70 analysed samples taken at different depth levels and distances from the source of the heat and/or water showed measurable transformation of original smectites. Newly formed gypsum bordered by illite aureole was detected in the upper part of the experimental set-up (backfill samples), i.e. in the...
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Summary of foreign knowledge about the origin and development of EDZ in crystalline rocks - research
Vavro, Martin ; Souček, Kamil ; Staš, Lubomír ; Vavro, Leona
Presented search summarizes findings of foreign research oriented on the origin and evolution of the excavation damaged zone in crystalline rocks with a particular focus on the essential results of experimental projects which were performed in Canada, Sweden, Finland, and Switzerland. The study is divided, excluding the introduction, into seven main chapters of the text, which gradually deal with: (1) definition of key terms, (2) overview of the main underground research laboratories in the world where EDZ assessment was conducted, (3) methods suitable for EDZ description and characterization, (4) main factors influencing the origin of failure around the excavations and time-dependent evolution of EDZ. An overview of important outcomes of EDZ experiments, focusing on the European hard rock laboratories (Stripa, Äspö, Onkalo/Olkiluoto and Grimsel), and their summary are presented in the final two chapters.\nThe review summarizing the published key findings and results of in situ experiments shows, that for rock in lower stress state, i.e. in no spalling environment, the extent and character of rock mass damage is typically dependent on the excavation method. Using mechanical excavation, rock damage zone with thickness less than 3 centimeters can be originated. The microcracks within this zone contribute to the increase of hydraulic conductivity of the rock mass. At some test sites (Äspö, Grimsel), where the tunnel boring machine technology was used, the damage zone was already detected in depth of less than 5 mm.\nOn the contrary, openings excavated by drilling and blasting are characterized by much more extensive damage zones up to several tens of centimeters in width. The damage progressively diminishes with the distance from the opening.
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Heat transfer in the storage cask and its impact on the environment
Marcell, Jan ; Slovák, Jiří (referee) ; Matal, Oldřich (advisor)
The main object of this diploma thesis is solving problems concerning heat transfer in disposal cannister for spent nuclear fuel. In forepart possibilities of conceptual solving according of disposal cannister to particular states are reviwed. On the basis of this a variant of possible protect of a nuclear fuel repository in the Czech republic has been chosen for calculationof a simplified model. Second part is computational solving that was divided into two parts. The first deals with calculation of heat transfer in disposal canister and is done by an analytical method. In the second part is calculation is done by numerical model. In this way region in near surroundings of this model of disposal cannister is analysed. Last part those diploma thesis deals with design of the storage of spacing among disposal canisters as well as optimum placing in underground part of nuclear fuel repository.
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