The European Journal of Physics N (EPJ-N)
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Supporting access to key pan-European research infrastructures and international cooperation
No full textLarge research infrastructures, especially nuclear ones, are extremely expensive to build and operate. Therefore, to develop expertise and competences in nuclear research is more efficient to have a limited number of complementary specialized large nuclear research infrastructures, shared by European researchers from different countries.
This paper describes three different actions to improve the European collaboration in the experimental nuclear research, namely open access to the nuclear research infrastructure of the JRC, the optimization of the use of research reactors in Europe and operation planning of the Jules Horowitz reactor currently under construction.
Supporting access to key pan-European research infrastructures strengthens research and innovation, avoiding duplication and optimising resources. It contributes to the European Research Area (ERA) and the European Strategy Forum on Research Infrastructures (ESFRI), as well as to maintaining competence in the EU, which is one of the objectives of the Euratom research and training programme
ROBBE – Robot-aided processing of assemblies during the dismantling of nuclear power plants
No full textFor a successful decommissioning and dismantling of an NPP (Nuclear Power Plant), correct and controlled processing of all components is necessary, whereby a large part of the work relates to coated (mainly painted) steel components, which make up a significant proportion of the total inventory of the power plant to be processed. The contamination of these components is reduced by removing the surface coating using UHP (Ultra-High-Pressure) water jet blasting technology. Thus, the decontaminated material is released to be recycled conventionally after receiving clearance in accordance with Chap. 3 StrlSchV (German Federal Law Gazette 2018 No. 41: StrlSchV, 2018). The manual processing of these individual parts is cost-intensive, so that an autonomous, automated solution is more economical while increasing throughput at repeatable high quality. ROBBE aims at implementing a robot-assisted, automated and autonomous decoating procedure of component groups using UHP water jet blasting technology and implements it ata German NPP in Biblis on an industrial, productive scale
Capturing the state-of-knowledge in EURAD knowledge management
No full textKnowledge about a wide variety of aspects is fundamental for the safe management and disposal of radioactive waste. This importance of Knowledge Management (KM) is also recognised by EURAD, the European Joint Programme on Radioactive Waste Management (RWM), which brings together over 100 organisations from different countries and backgrounds (Waste Management Organisations, Technical Support Organisations, and Research Entities). This vast resource of expertise and experience feeds into several dedicated EURAD KM programme activities. One of these activities, led by Work Package 11 State-of-Knowledge (WP11 SoK), is capturing experts’ views on the current State-of-Knowledge on topics relevant to RWM and making this knowledge accessible through dedicated documents. For this, EURAD has developed the “Goals Breakdown Structure” (GBS), which provides a framework in which topics are structured thematically, as well as a hierarchy of documents that allows accessing knowledge on different levels of detail (see EURAD Roadma
Modelling of radioactive dust for dose calculations with stochastic geometries
No full textStochastic geometries in Monte-Carlo simulations enable to simulate complex configurations such as the repartition of possible radioactive dust in a glove box. This paper compares several dust models that represent more or less explicitly the heterogeneous repartition of dust speckles in space. Indeed, assessing the contribution of dust to the dose received by the hands of an operator is a key problem for glove boxes. Results show that homogeneous models generally overestimate the dose, which is correct for radioprotection studies, but that dust aggregates produce doses that are much smaller than those obtained by homogenising dust. These heterogeneous models can also help estimating deposited dust quantities from dose measurements inside the glove box, whereas an homogenous model would grossly underestimate dust quantity
Simplified approach to determine the requirements of a “flexible nuclear reactor” in power system with high insertion of variable renewable energy sources
No full textThe objective of the paper is to study the potential behaviour of a power system with high share of nuclear and less thermal plants, in which variable RES insertion increases − for example the French case −, in order to determine the specifications for the design of a potential nuclear reactor with high “manoeuvrability”. Moreover, the flexible reactor may participate more in the supply − demand balance and in particular during large frequency fluctuations caused by the high variability of RES. The studies are carried out with the PowerFactory software, which make it possible to highlight specific needs regarding the power ramp for an “ideal” flexible nuclear reactor. Using a benchmark network, the Kundur “2 areas-4 machines”, the flexibility requirements are obtained as a function of the grid disturbances. For this purpose, the penetration of variable RES is progressively increased, while nuclear power is reduced and thermal power plants are totally suppressed. The study shows that a drop in RES production directly impacts the minimal frequency. A faster response speed of nuclear power makes it possible to restore this stability and return to normal operating conditions imposed by the grid operator. This paper describes therefore the process of obtaining the flexibility criterion for different cases of insertion of variable RES
Training and mobility in EU projects EURAD and PREDIS
No full textKnowledge management (KM) is critical to ensure safe and sustainable radioactive waste management. The European Commission is encouraging KM through the Waste Directive. EURAD and PREDIS are projects funded by the European Commission, including work packages devoted to Knowledge Management. EURAD has set up a “School of RWM”, launched in 2020. To establish a portfolio of training courses, currently existing training initiatives in the field of RWM were mapped. A gap analysis was carried out to detect current unfulfilled needs for courses on specific topics. The School of RWM has already organized two training courses responding to the perceived needs. Besides training courses, both projects regularly organize topical webinars, which are related to RWM & Predisposal-related themes. Both projects launched a dedicated mobility program, allowing their beneficiaries to perform technical visits to infrastructures, undertake internships and set up exchange programs between institutions within EURAD/PREDIS. In addition, PREDIS also financially supports participation in training courses and events. Finally, both projects support their respective student communities, including masters, Ph.D. students, and postdocs. In order to improve their efficiency, EURAD and PREDIS KM will be merged in the proposed upcoming EURAD-2 program
Probabilistic Safety Assessment for internal and external events on nuclear power plants and on mitigation strategies/H2020 European projects NARSIS, R2CA and BESEP
No full textThe NARSIS project aimed at improving assessment methodologies to be integrated into “extended Probabilistic Safety Assessment” (PSA) procedures for nuclear plants in case of single, cascade and combined external natural events. An open-access framework tool has been released to build multi-hazard scenarios, and various risk integration approaches (e.g., Bayesian Networks) have been implemented and compared, identifying their advantages and limits for further collaborative research activities. The R2CA project aims at harmonizing the safety analysis methods for best estimate evaluations of the radiological consequences, in case of Design Basis Accidents and Design Extension Conditions without significant fuel melting. It is planned to improve models and upgrade existing simulation tools and calculation chains used in safety studies. Finally, the BESEP project is to support safety margin determination, by developing best practices for safety requirement verification against external hazards, using efficient and integrated set of Safety Engineering practices and PSA. The project is carried out in a benchmark exercise based on case studies previously performed by the consortium participants. All three projects aim to improve nuclear safety within the European research and development framework. The research objectives are achieved by the development and improvement of proven and justified safety assessment methodologies for the verification of stringent safety requirements of nuclear industry
EURADWASTE’22 Paper – Host rocks and THMC processes in DGR
No full textDeep geological disposal aims to contain and isolate radioactive waste from the biosphere. Repository systems are made of multiple barriers working together, typically comprising the natural geological barrier provided by the repository host rock and its surroundings and an engineered barrier system. Due to their excellent properties for the confinement of contaminants, including low permeability, high sorption capacity, and swelling/self-sealing capacity, clayey materials are considered as engineered and/or natural barriers in most repository designs under development in Europe. During the lifetime of the repository, clay barriers will be exposed to perturbations, among which those are resulting from gas and heat production within the system. It is important to verify that these perturbations will not be detrimental to the good functioning of these barriers. In this paper, it is shown how the two EURAD R&D work packages, GAS and HITEC use a combination of experimental and modelling approaches to increase the understanding and predictability of the impact on clay barriers of the fundamental processes and their couplings related to gas and heat transport respectively, providing building blocks to support the evaluation of the robustness of the repository concepts
Overview of knowledge management in EURAD
No full textKnowledge management is a core activity for the European Member States (MSs) implementing the Council Directive EC 2011/70/EURATOM. Twenty-one MSs and two associated countries have mandated their respective radioactive waste management, safety and research organisations to contribute to the European Joint Programme on Radioactive Waste Management (EURAD). EURAD has established a Knowledge Management and Networking Programme which supports the capturing of knowledge and its transfer among organisations, Member States and generations. EURAD as a Joint Programming has an utmost advantage, compared to individual projects, as it provides:
processes for knowledge sharing, for example interaction between the different radioactive waste management (RWM) actors to find out what is already known and what is most useful to investigate further
Towards an optimized management of accidents
No full textNuclear safety has been one of the main research domains in EURATOM programs for decades, and accident prevention and mitigation have drawn much of the attention paid over the years to this framework. In the essence of this interest are designs of reliable systems, accurate methods to estimate risk, and a permanent search for optimizing accident management. This is the focus of PIACE, MUSA, and AMHYCO projects. A fully passive system for decay heat removal in off-nominal conditions based on the concept of isolation condenser is the subject of PIACE. A harmonized approach for analyzing uncertainties and sensitivities associated with severe accidents, particularly with the source term to the environment, is the final aim of MUSA. And finally, AMHYCO is exploring the potential for enhancing the management of combustible gas risk. Despite the project’s diversity, they all will converge on the same outcome: an optimization of nuclear safety from better safety systems, risk estimating methods, and in-accident guidelines. These projects have received funding from the H2020 EURATOM research and training program under grant agreements 847715 (PIACE), 847441 (MUSA), and 945057 (AMHYCO)