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Information × Registration Number 0217U001271, 0115U000496 , R & D reports Title Development of methods for reducing the radiation dose in the handling and storage of radioactive waste in the NPP popup.stage_title Head Girka Igor Oleksandrovich, Registration Date 02-02-2017 Organization Kharkov National University named after V.N. Karazin popup.description2 The aim of this work is to develop practical techniques designed to reduce radiation exposure to NPP personnel and the environment at storage and handling RAW, namely, taking into account the influence of shielding constructions and arrangement of the containers on the radiation propagation, as well as a strategy of loading the storages (and general purpose containers) with baskets with RAW of different activity and spectral composition. The object of the research is the fields of external gamma radiation of containers and hangar storages of various geometry, loaded with RAW of different elemental and radionuclide composition. The method of research and development is the processes and mechanisms of gamma rays propagation, including the passage of radiation, with its spectral composition taken into account, in heterogeneous shielding constructions in the form of multi-tier containers with RAW of different activity arranged on the earth surface in the presence of natural or artificial shields. We have developed a database of characteristics for RAW that are stored at the production sites of Zaporizhzhya, South-Ukrainian, Rivne and Khmelnitsky NPPs of Ukraine, and processing of this RAW for its compaction and further storage at the NPP production sites is planned. To simulate the radiation propagation from cylindrical radiation sources located behind the shielding constructions, some geometrical modules of combined geometry were developed in PENELOPE, MCNP, VOLUME_M, and Microshield code packages. Modification of PENELOPE MCNP package codes was carried out using Variance Reduction methods allowing to significantly reduce the calculation time when using the Monte-Carlo methods in complex geometry. The methodology of calculation of gamma quanta fields outside the shielding containers loaded with cylindrical baskets with RAW of different activity and different radionuclide composition was developed. This allows calculating the dose rate both for separate containers and for their combination with the influence of biological protection and RAW storage time taken into account. The technique is based on the use of data on the isotopic composition of solid and liquid RAW of Ukrainian NPP and to determine the optimal strategy for reducing the RAW volume in the recycling process at the waste reprocessing complexes (RWRC) thus ensuring minimal radiation exposure to personnel and the environment. We developed an algorithm for arrangement of containers loaded with RAW of different activities and different isotope composition at the storage sites or storages of hangar type that provides minimum dose rate around the storage facilities. Taking as an example the containers for dry storage of spent nuclear fuel (Zaporizhzhya NPP) and containers for storage of conditioned RAW (Novo Voronezh NPP) we determined the layout of containers arrangement at the storage site and in the storage of hangar type. The potential reduction of RD at least by15% due to the optimal arrangement of containers according to their capacity was shown. The developed techniques can be used to minimize radiation doses to personnel and the environment when handling radioactive waste at Ukrainian NPPs, first of all, for the planned conditioned RAW storage of hangar type at the Zaporizhzhya NPP. Product Description popup.authors Є. Рудичев І. Гірка В. Пишкін В. Рудичев Г. Ветрова Г. Махненко popup.nrat_date 2020-04-02 Close