Sulphur-Assisted Corrosion in Nuclear Disposal Systems

Sulphur-Assisted Corrosion in Nuclear Disposal Systems
Author: Damien FĂ©ron
Publisher: CRC Press
Total Pages: 174
Release: 2020-11-26
Genre: Technology & Engineering
ISBN: 1000107116

In the different disposal concepts for high-level nuclear waste, corrosion of the metallic barriers and in particular the overpack/container is a major issue. It is imperative for performance assessment to predict the lifetime of these containers. In the lifetime prediction of metallic barriers for the disposal of high level nuclear waste (HLW) or of spent fuel, the presence of (reduced) sulphur species is an issue of growing importance, as the sulphur species are involved in localised corrosion phenomena. The international workshop on Sulphur-Assisted Corrosion in Nuclear Waste Disposal Systems (SACNUC2008) aimed to provide an exchange of information on the influence of sulphur species on the corrosion of metallic barriers. This workshop was a co-organisation of the Belgian Nuclear Research Centre, SCK*CEN, and the Belgian Agency for the Management of Radioactive Waste and Enriched Fissile Materials, ONDRAF/NIRAS, under the auspices of the European Federation of Corrosion (EFC event N 311). The proceedings are divided into five chapters: Chapter 1 provides a general overview of the disposal concepts of nuclear waste and the role of corrosion. Chapter 2 explains the mechanism of sulphur-induced corrosion processes. This chapter also contains information from outside the nuclear disposal field in which sulphur is known to act as a detrimental factor (e.g. oil and gas industry). Chapter 3 addresses the role of microbial processes in sulphur-assisted corrosion. Chapter 4 covers the modelling of sulphide-assisted corrosion. Chapter 5 is devoted to a panel discussion aiming to identify open issues in the investigation of sulphur-assisted corrosion phenomena and how to incorporate these in robust lifetime prediction of metallic barriers.

Gas Generation and Migration in Deep Geological Radioactive Waste Repositories

Gas Generation and Migration in Deep Geological Radioactive Waste Repositories
Author: R.P. Shaw
Publisher: Geological Society of London
Total Pages: 260
Release: 2015-06-11
Genre: Science
ISBN: 1862397228

Understanding the behaviour of gases in the context of radioactive waste disposal is a fundamental requirement in developing a safety case for the disposal of radioactive waste. Of particular importance are the long-term performance of bentonite buffers and cement-based backfill materials that may be used to encapsulate and surround the waste in a repository, and the behaviour of plastic clays, indurated mudrocks and crystalline formations that may be the host rocks for a repository. The EC Euratom programme funded project, FORGE, has provided new insights into the processes and mechanisms governing gas generation and migration with the aim of reducing uncertainty. This volume brings together papers on aspects of this topic arising from both the FORGE project and work undertaken elsewhere. This has been achieved by the acquisition of new experimental data coupled with modelling, through a series of laboratory and field-scale experiments performed at a number of underground research laboratories throughout Europe.

Computer Modeling of Nuclear Waste Storage Canister Corrosion

Computer Modeling of Nuclear Waste Storage Canister Corrosion
Author:
Publisher:
Total Pages:
Release: 1979
Genre:
ISBN:

Current plans for nuclear waste disposal include placing the waste in a canister to isolate it from the repository environment for 1000 years. Corrosion prediction techniques are currently inadequate to quarantee the canister performance over this length of time. We are attempting to better predict the corrosion process with the help of computer modeling. We developed a program to calculate anodic and cathodic polarization curves using Tafel slopes, equilibrium exchange current densities, and other electrochemical parameters obtained from the experimental corrosion literature. The model generates and displays polarization curves for different values of environmetal parameters such as temperature, pH, and concentrations of pertinent species in the vicinity of the canister material. For the case of uniform corrosion in acidic media, our model predicts corrosion rates in fair agreement with literature values.

Reactive Transport Modeling

Reactive Transport Modeling
Author: Yitian Xiao
Publisher: John Wiley & Sons
Total Pages: 689
Release: 2018-03-14
Genre: Science
ISBN: 1119060028

Teaches the application of Reactive Transport Modeling (RTM) for subsurface systems in order to expedite the understanding of the behavior of complex geological systems This book lays out the basic principles and approaches of Reactive Transport Modeling (RTM) for surface and subsurface environments, presenting specific workflows and applications. The techniques discussed are being increasingly commonly used in a wide range of research fields, and the information provided covers fundamental theory, practical issues in running reactive transport models, and how to apply techniques in specific areas. The need for RTM in engineered facilities, such as nuclear waste repositories or CO2 storage sites, is ever increasing, because the prediction of the future evolution of these systems has become a legal obligation. With increasing recognition of the power of these approaches, and their widening adoption, comes responsibility to ensure appropriate application of available tools. This book aims to provide the requisite understanding of key aspects of RTM, and in doing so help identify and thus avoid potential pitfalls. Reactive Transport Modeling covers: the application of RTM for CO2 sequestration and geothermal energy development; reservoir quality prediction; modeling diagenesis; modeling geochemical processes in oil & gas production; modeling gas hydrate production; reactive transport in fractured and porous media; reactive transport studies for nuclear waste disposal; reactive flow modeling in hydrothermal systems; and modeling biogeochemical processes. Key features include: A comprehensive reference for scientists and practitioners entering the area of reactive transport modeling (RTM) Presented by internationally known experts in the field Covers fundamental theory, practical issues in running reactive transport models, and hands-on examples for applying techniques in specific areas Teaches readers to appreciate the power of RTM and to stimulate usage and application Reactive Transport Modeling is written for graduate students and researchers in academia, government laboratories, and industry who are interested in applying reactive transport modeling to the topic of their research. The book will also appeal to geochemists, hydrogeologists, geophysicists, earth scientists, environmental engineers, and environmental chemists.

Theoretical Modeling of Crevice and Pitting Corrosion Processes in Relation to Corrosion of Radioactive Waste Containers

Theoretical Modeling of Crevice and Pitting Corrosion Processes in Relation to Corrosion of Radioactive Waste Containers
Author:
Publisher:
Total Pages: 9
Release: 1989
Genre:
ISBN:

A mathematical and numerical model for evaluation of crevice and pitting corrosion in radioactive waste containers is presented. The model considers mass transport, mass transfer at the metal/solution interface, and chemical speciation in the corrosion cavity. The model is compared against experimental data obtained in artificial crevices. Excellent agreement is found between modeled and experimental values. The importance of full consideration of complex ion formation in the aqueous solution is emphasized and illustrated. 10 refs., 5 figs.

Comsol Modelling of Uniform Corrosion of Used Nuclear Fuel Canisters

Comsol Modelling of Uniform Corrosion of Used Nuclear Fuel Canisters
Author: Mohd Moinuddin
Publisher:
Total Pages: 0
Release: 2018
Genre:
ISBN:

Uniform corrosion of copper can occur in spent nuclear fuel canisters placed in deep geological repositories (DGR). To estimate the minimum thickness for safe design of canisters, it is necessary to analyze the corrosion rate. Copper Corrosion Model (CCM) has been used to model the corrosion process taking into account processes including adsorption/desorption, precipitation/dissolution, oxidation, and parameters including oxygen concentration, chloride, moisture and associated rate constants. In this work, CCM has been incorporated in COMSOL and validated with CCM. Once validated, the COMSOL model was used to examine the sensitivity of various parameters with respect to copper corrosion. It was found that initial chloride concentration, adsorption/desorption of cupric ions are parameters that most effect copper corrosion. The developed model can be used to simulate the uniform corrosion process under DGR conditions with more complexity including variation in temperature, saturation and pressure, and aid in the design of copper canisters.