Contact
Dr. Astrid Barkleit
a.barkleit
hzdr.de
Phone: +49 351 260 3136
+49 351 260 2512
+49 351 260 2518
Development of a method for pre-activity and dose rate calculations of components in the reactor vicinity based on neutron fluence distributions (EMPRADO)
Summary:
The aim of the collaborative project is to develop a standardized method that calculates the specific and temporal progression of activation for reactor components and near-reactor concrete or construction elements based on the power history of a nuclear reactor. A non-destructive and early radiological characterization in the region of the reactor core is thus possible, which is required for an optimal planning of the decommissioning. This can make a significant contribution to minimize the radioactive waste and the radiation exposure of personnel during the decommissioning. The method will be developed using the example of a "Vor-Konvoi" pressurized water reactor and validated with experiments.
In the HZDR subproject, the required exact 3D neutron fluence calculations and the experimental activation determination will be carried out. The Monte-Carlo method is a recognized method for such simulations with complicated geometries. Therefore, the international widely-used program MCNP6 is mainly used in the project. For the geometry model, original design documents are used to represent the geometry as accurately as possible in the calculations. The neutron sources will be specified as external source. These are based on corresponding power histories. Due to the large spatial dimensions, one focus of the work will be the optimization of the simulation. The using of variance-reducing methods will be indispensable.
For validation of the calculation results neutron flux measurements on the basis of activation foils will be carried out at certain NPPs. Different metal films are installed at selected locations near the reactor and irradiated during an operating cycle. The generated activities will be measured by Gamma spectroscopy and Liquid Szintillation Counting (LSC) and compared with the calculation results.
Publications
Journal papers
Conference contributiona (Master thesis, Talks and Posters)
Estimation of neutron fluence distribution within German PWR components for decommissioning studies
Rachamin, R.; Barkleit, A.; Konheiser, J.; Seidl, M.
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Poster
The Seventeenth International Symposium on Reactor Dosimetry (ISRD-17), 21.-26.05.2023, Lausanne, Switzerland -
Contribution to proceedings
The Seventeenth International Symposium on Reactor Dosimetry (ISRD-17), 21.-26.05.2023, Lausanne, Switzerland
Activation calculations of selected RPV internal components for optimal decommissioning of nuclear power plants
Rachamin, R.; Konheiser, J.; Seidl, M.
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Lecture (Conference)
15th workshop on Shielding aspects of Accelerators, Targets, and Irradiation Facilities (SATIF-15), 20.-23.09.2022, East Lansing, USA -
Contribution to proceedings
15th workshop on Shielding aspects of Accelerators, Targets, and Irradiation Facilities (SATIF-15), 20.-23.09.2022, East Lansing, USA
Dosimetry for Decommissioning of Nuclear Power Plants
Rachamin, R.; Konheiser, J.; Barkleit, A.; Seidl, M.
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Contribution to proceedings
14th International Conference on Radiation Shielding and 21st Topical Meeting of the Radiation Protection and Shielding Division (ICRS 14/RPSD 2022), 25.-29.09.2022, Seattle, USA -
Lecture (Conference)
14th International Conference on Radiation Shielding and 21st Topical Meeting of the Radiation Protection and Shielding Division (ICRS 14/RPSD 2022), 25.-29.09.2022, Seattle, USA -
Invited lecture (Conferences)
ANS Annual Meeting, 11.-14.06.2023, Indianapolis, IN, USA
Neutron Fluence Calculations for the Dismantling and Decommissioning of a German PWR
Rachamin, R.; Konheiser, J.; Barkleit, A.; Marcus, S.
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Lecture (Conference)
AAA Workshop, GRS GmbH, 02.12.2019, Garching, Germany
Internal type of HZDR-publication(s): Thesis / Students' report
"Online First" included
Search title/ authors: ("Zilbermann, M. E.")
Comparative structural and (radio-)chemical investigations of activated cement and concrete samples
Zilbermann, M. E.
To help with the decommissioning of the unit 2 of the Greifswald NPP, this study aims at determining the activities of 3H, 14C, 60Co, 152Eu and 154Eu in the concrete to estimate the maximal activity in the entire bioshield.
The study will focus on the activity as a function of depth in the concrete layer, as well as composition of the mineral phases. As the flux of neutrons generated during fission reaction encounters the mineral phases of concrete, the natural elements present in these phases absorb neutrons, which leads to the formation of their radioactive isotopes. Therefore, the elemental composition of each mineral phase in the concrete is important in the activation process, and the concrete being a heterogeneous material, different phases will present different activities.
A precise knowledge of the activities and of the elemental composition of the concrete and its mineral phases helps refining the models to calculate and predict the activities in a long-term scale. The calculations and the experimental results support the sorting of the materials for disposal.
This study will analyze the concrete with three main objectives:
- Activation;
- Chemical composition;
- Structure of the concrete and mineral phases.
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Master thesis
TU Dresden, 2023
Mentor: Prof. Dr. Thorsten Stumpf, Dr. Astrid Barkleit
