Zohreh Gholamzadeh, Seyed Amir Hossein Feghhi, Leila Soltani, Marzieh Rezazadeh, Claudio Tenreiro and Mahdi Joharifard
Decrease of the economically accessible uranium resources and the inherent proliferation resistance of thorium fuel motivate its application in nuclear power systems. Estimation of the nuclear reactor’s neutronic parameters during different operational situations is of key importance for the safe operation of nuclear reactors. In the present research, thorium oxide fuel burn-up calculations for a demonstrative model of a heavy water- -cooled reactor have been performed using MCNPX 2.6 code. Neutronic parameters for three different thorium fuel matrices loaded separately in the modelled thermal core have been investigated. 233U, 235U and 239Pu isotopes have been used as fissile element in the thorium oxide fuel, separately. Burn-up of three different fuels has been calculated at 1 MW constant power. 135X and 149Sm concentration variations have been studied in the modelled core during 165 days burn-up. Burn-up of thorium oxide enriched with 233U resulted in the least 149Sm and 135Xe productions and net fissile production of 233U after 165 days. The negative fuel, coolant and void reactivity of the used fuel assures safe operation of the modelled thermal core containing (233U-Th) O2 matrix. Furthermore, utilisation of thorium breeder fuel demonstrates several advantages, such as good neutronic economy, 233U production and less production of long-lived α emitter high radiotoxic wastes in biological internal exposure point of view
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Katarzyna Kiegiel, Grażyna Zakrzewska-Kołtuniewicz, Dorota Gajda, Agnieszka Miśkiewicz, Anna Abramowska, Paweł Biełuszka, Bożena Danko, Ewelina Chajduk and Stanisław Wołkowicz
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Goran Manić, Vesna Manić, Dragoslav Nikezić and Dragana Krstić
radionuclides in the soil and the environment of the city of Nis for the period 2011/2012 year. For the Directorate for Economy, Sustainable Development and Environmental Protection of the city of Niš, Niš. (in Serbian).
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