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Din avgränsning ger 112 träffar.

• 2016:01 Literature Study on Sparse Channel Interpretation and Modeling

  Channelling has been observed in laboratory and field experiments at various scales. However, it is still an open research issue whether a sparse channel network is likely to be a better model than the fracture network model for representing the flow system in fractured rocks. The present report presents a literature study to bring together information useful for addressing this issue.

  Innehållstyp: Publikationer

• 2016:30 Measurement of Parameter Values for Predicting Corrosion Phenomena on Copper in Swedish HLNW Repositories

  Passivity breakdown and pitting on pure copper, the assumed material for the canisters for the isolation of high-level nuclear waste in Sweden, has been studied in simulated, sulphide- and chloride containing granitic rock groundwater and the data are interpreted in terms of the Point Defect Model (PDM). The results indicated that a sulphide barrier layer forms on the copper surface, and that...

  Innehållstyp: Publikationer

• 2017:18 FEM analysis of the mechanical integrity for the canister intended for storage of spent nuclear fuel with regard to copper creep ductility

  Background For final storage of spent nuclear fuel it is suggested by the Swedish nuclear fuel and waste management company (SKB) to emplace the nuclear fuel into copper canisters which are surrounded by bentonite clay at approximately 500 meters’ depth into granitic rock. After emplacement of the canisters Bentonite swelling due to water saturation and hydrostatic pressure build up the...

  Innehållstyp: Publikationer

• 2017:02 Slow strain rate testing of copper in sulfide rich chloride containing deoxygenated water at 90 °C

  Background Stress corrosion cracking (SCC) can occur in materials from the combined influence of tensile stress and a corrosive environment. It has previously been shown in the literature, that copper can be sensitive to SCC in the presence of sulfide containing water. Since both tensile...

  Innehållstyp: Publikationer

• 2014:30 Modelling Approaches to C-14 in Soil-Plant Systems and in Aquatic Environments

  Substantial expertise on carbon biogeochemistry already exists in the fields of plant physiology and aquatic ecology and therefore is it beneficial to draw on this to identify the important issues. A paper describing the BIOPROTA C-14 model inter-comparisons, and plans for the forward programme was published in Radiocarbon Journal. Further studies on C-14 (including modelling, model...

  Innehållstyp: Publikationer

• 2012:11 Issues in the corrosion of copper in a Swedish high level nuclear waste repository

  The objective with this research project was to increase knowledge in the area of copper corrosion in the planned repository environment and obtain information on how copper corrosion evolves during the assessment period of 100 000 years. The equilibrium chemical composition of groundwater close to the canister as a function of temperature has been calculated by use of a thermodynamics code...

  Innehållstyp: Publikationer

• 2011:26 The influence of temperature and fluid pressure on the fracture network evolution around deposition holes of a KBS-3V concept at Forsmark, Sweden

  In preparation for the review of SKB’s license application for disposal of spent nuclear fuel, SSM is conducting studies to evaluate the performance of the multi-barrier principle on which the KBS-3 concept is based. Copper canisters containing the spent nuclear fuel are placed into granitic bedrock at about 500 m depth and embedded in clay. Thus, the rock, the clay and the copper canister...

  Innehållstyp: Publikationer

• 2011:12 Analysis of Barrier Performance: Modelling of Copper corrosion scenarios with and without buffer erosion

  The purpose of this project was to develop a numerical modelling capacity to address the corrosion of the copper canister under gradually changing transport conditions caused by buffer erosion and removal of buffer mass. Due to the complexity of this task, such a model cannot be realistic in all respects, but the present effort should address the feasibility of solving numerical and...

  Innehållstyp: Publikationer

• 2011:11 Handling Interfaces and Time-varying Properties in Radionuclide Transport Models

  Quintessa’s QPAC code has been used to investigate the Qeq approach. The conclusions from this simulation study are the following. The basic approach to calculating Qeq values is sound, however, narrow channels could lead to the same release as larger fractures with the same pore velocity, so a channel enhancement factor of √10 should be considered. A spalling zone that increases the area of...

  Innehållstyp: Publikationer

• 2013:32 Upparbetning av utbränt kärnbränsle - En studie med fokus på exportkontroll

  Rapporten beskriver principerna för upparbetning samt egenskaperna hos utbränt kärnbränsle där sammansättningen hos det i reaktorn bildade plutoniumet är av avgörande betydelse för kärnvapenframställning till skillnad från civil upparbetning. Rapporten går igenom ett antal upparbetningsmetoder, både äldre metoder samt nya,...

  Innehållstyp: Publikationer