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Information × Registration Number 0219U003517, 0117U004863 , R & D reports Title Radiation safety in the transport of spent nuclear fuel with high burnup for storing dry method popup.stage_title Head Girka Igor Oleksandrovich, Registration Date 17-01-2019 Organization Kharkov National University named after V.N. Karazin popup.description2 The aim of this work is to develop techniques for determining the dose rate produced by neutrons and gamma rays around the transport containers during transportation of SNF with increased burnup, as well as methods for taking stock of thermal loads and estimating the body burden on the personnel and the residents while eliminating possible consequences of accidents. The object of research and development are radiation fields, which are generated by neutrons and gamma quanta induced by SNF outside the containers during transportation and storage. The method of research and development are the processes and mechanisms of emission and propagation of gamma and neutron radiations, with changes in their spectral compositions in time taken into account. The MCNP package was used to develop models for calculating radiation of spent nuclear fuel from VVER-1000 during their transportation in a module, which is similar to "HI-STAR 190UA", and in TK-13 transport container, in which spent nuclear fuel of Ukrainian NPPs is transported to the Russian Federation. Calculations of the isotopic composition of SNF with different levels of burnout and cooling time and the contributions of certain radionuclides to heat release were carried out in the FISPACT package. To assess the thermal state of SNF, when conveyed in a transport container, a mathematical model of thermal processes was developed. A comparative analysis of the protective properties of steel (TK-13) and lead (HI-STAR 190UA) against gamma quanta of SNF was performed. The optimal parameters of protection: Pb for gamma-quanta, and Holite-A for neutrons, ensuring safe transportation of 31 SFAs were determined. It was shown that the maximum contribution to the gamma quanta radiation for protection using Fe and Pb is provided by 154Eu isotope, and the second as to its contribution for Fe is 134Cs, and for Pb - 144Pr. The studies showed that at biological shielding thickness of 30 cm of steel (or equivalent of lead) photons with initial energy of less than 0.7 MeV did not contribute to the external radiation. That is, 137Cs isotope, whose activity in SNF is the highest, does not contribute to the surface dose rate. It is shown that the dose rate of gamma quanta on the container surface is produced by 18 SFAs along the storage basket perimeter. An optimal layout of SFAs with different storage time is proposed. The analysis of radiation accidents was performed, a technique for calculating radiation at large distances, with shading due to the relief taken into account, was developed. HotSpot and COSYMA packages were used to analyze the consequences of a planned accident and of a planned maximal one during SNF transportation. Product Description popup.authors C. Альохіна Є. Рудичев І. Гірка В. Вітько В. Пишкін В. Рудичев Г. Ветрова Г. Махненко popup.nrat_date 2020-04-02 Close