Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 15 of 15 for “"geological disposal"”.
-
Dissolution of mixed uranium thorium oxides under geological disposal conditions
Uranium dioxide alone offers enough complexity to provide the subject matter for 50 years of dissolution studies, not least due to uranium’s redox sensitivity and the orders of magnitudes between the solubility of U(IV) and U(VI). The addition of plutonium dioxide as a solid solution opens up a …
-
The role of accessory minerals in inhibiting bentonite erosion in the geological disposal of higher activity radioactive waste
… of concern in the approval of safety cases for disposal of radioactive waste in crystalline rock. Currently, quantitative mass loss assessments are based on a 100% montmorillonite buffer and lead to unacceptable mass loss predictions. In practice however, the buffer will be comprised of ≈80% …
-
Predicting radioactive waste glass properties with machine learning and modelling
… waste (HLW), ultimately in preparation for deep geological disposal. This data has largely been collected in isolation, and there has been an open question whether this data could be of value when used collectively. With this motivation, this PhD has aimed to either predict unstructured glass …
-
Experiments on the dynamics of buoyancy-driven flows in reactive porous media
… media are of great interest to a number of geological and industrial situations where fluid of one composition invades a formation containing a solid component with which it can react. Geological situations include dolomitisation of limestone following invasion of sea water into freshwater …
-
Geomechanical aspects of Sintered Silicon Carbide (SSiC) waste canisters for disposal of high level radioactive waste
… waste (HLW) poses threat to the biosphere. Geological disposal is accepted as a safe way for HLW disposal. Waste canisters made of Sintered Silicon Carbide (SSiC) are proposed and geomechanical safety aspects relating to such SSiC canisters are investigated. First part of the thesis reviews …
-
Enhancing trust in US nuclear waste management institutions
… of US policymakers to develop a permanent geological disposal solution has led to the accumulation of spent nuclear fuel and high-level radioactive waste material at nuclear power plants and former weapons manufacturing facilities. This situation poses a growing long-term public safety …
-
Advancing solvent extraction technology for improved management of contaminated liquors
… size and environmental impact of any subsequent geological disposal. In addition, separation of these actinides from the lanthanides is essential for a strategy which aims to put the minor actinides back into the fuel cycle through transmutation by neutron bombardment, which would increase fuel …
-
Alteration mechanisms of spent nuclear fuel and characterization of potential uranium secondary phases.
… proliferation make a strong case for direct disposal of SNF in deep underground geological disposal facilities. The escape of radionuclides from underground spent nuclear fuel disposal facilities will likely result from anoxic dissolution of spent nuclear fuel by intruding groundwater with …
-
Electrochemical and Modelling Studies on Simulated Spent Nuclear Fuel Corrosion under Permanent Waste Disposal Conditions
The safety assessment models for the deep geological disposal of spent nuclear fuel require a fundamental understanding of the corrosion of spent fuel in a failed waste container. The overall research goal of this project is to investigate the corrosion of simulated spent fuel under permanent …
-
Investigating the Influence of Mechanical anisotropy on the Fracturing Behaviour of Brittle Clay Shales with Application to Deep Geological Repositories
… as possible host rock formations for the deep geological disposal of radioactive waste. However, one main concern is that the favourable long-term isolation properties of the intact rock mass could be negatively affected by the formation of an excavation damaged zone (EDZ) around the …
-
Developing an understanding of the relationship between the durability of simplified and complex UK radioactive waste glasses
… disposing of radioactive waste glass within a geological disposal facility requires a thorough understanding of the kinetics and mechanisms of their aqueous dissolution over geological timescales. Whilst a significant number of studies have taken place on international waste glass compositions, …
-
Exploration of Hydrogen Gas Evolution from Radioactive Sludges
… place for radioactive waste in the UK is a geological disposal facility that will be built at a location in the UK, which has yet to be chosen, at some unspecified time in the future. To safely commit a waste material into this facility requires knowledge about the long-term behaviour of the …
-
Brittle-viscous deformation cycles at the base of the seismogenic zone in the continental crust
… (SW Finland), located at the site of a deep geological repository for nuclear waste. Combined microstructural analysis, electron backscatter diffraction (EBSD), and mineral chemistry were applied to reconstruct the variations in pressure, temperature, fluid pressure, and differential stress …
-
Mechanical properties and microcracking behaviour of heterogeneous rocks after high-temperature treatment
… as deep geothermal energy exploitation and the geological disposal of high-level radioactive nuclear waste, plays a critical role in ensuring national energy security, optimizing resource utilization, and addressing environmental protection challenges. These projects contribute to the …
-
The effect of radiation damage by fission fragments on the structural stability and dissolution of the UO2 fuel matrix
The aim of this work was to study the separate effect of fission fragment damage on the structural integrity and matrix dissolution of uranium dioxide in water. Radiation damage similar to fission damage was created by irradiating bulk undoped and doped ‘SIMFUEL’ disks of UO2, undoped bulk CeO2 and …