Trip turbine transient and stability analysis of two different fuel assembly designs aimed for the recycling of minor actinides and plutonium in BWRs

Thermal reactors have been considered as interim solution for transmutation of minor actinides recycled from spent nuclear fuel. Various studies have been performed in recent decades to realize this possibility. This paper presents the neutronic feasibility study on transmutation of minor actinides as burnable poison in the VVER-1000 LEU (low enriched uranium) fuel assembly. The VVER-1000 LEU fuel assembly was modeled using the SRAC code system, and the SRAC calculation model was verified against the MCNP6 calculations and the available published benchmark data. Two models of minor actinide loading in the LEU fuel assembly have been investigated: homogeneous mixing in the UGD (Uranium-Gadolinium) pins and coating a thin layer to the UGD pins. The consequent negative reactivity insertion by minor actinides was compensated by reducing the gadolinium content and boron concentration. The reactivity of the LEU assembly versus burnup and the transmutation of minor actinide nuclides were examined in comparison with the reference case. The results demonstrate that transmutation of minor actinides as burnable poison in the VVER-1000 reactor is feasible as minor actinides could partially replace the functions of gadolinium and boric acid for excess reactivity control.

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Estimation of the Amounts of Curium and Americium Isotopes in SNF of the BN-600 Reactor

KnE Engineering ◽

10.18502/keg.v3i3.1646 ◽

2018 ◽

Vol 3 (3) ◽

pp. 460

Author(s):

E.I. Lukyan ◽

G.L. Khorasanov ◽

А.М. Terekhova

Keyword(s):

Fuel Assembly ◽

Nuclear Fuel ◽

Spent Nuclear Fuel ◽

Physical Characteristics ◽

Reactor Fuel ◽

Minor Actinides ◽

Software Complex ◽

Reactor Fuel Assembly

The neutron-physical characteristics of curium and americium in spent nuclear fuel (SNF) of the BN-600 reactor were considered in the work. With the help of the Serpent software complex, several models of the BN-600 reactor fuel assembly with different enrichment of fuel by U-235 were built. In BN-600, with the probability of dividing Am-241 by no more than 15%, incomplete burning of minor actinides (MA) occurs and even the accumulation of Cm-244, which is dangerous for storage.

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Study on transmutation efficiency of the VVER-1000 fuel assembly with different minor actinide compositions

Nuclear Science and Technology ◽

10.53747/jnst.v9i4.134 ◽

2021 ◽

Vol 9 (4) ◽

pp. 16-26

Author(s):

Vinh Thanh Tran ◽

Thanh Mai Vu ◽

Van Khanh Hoang ◽

Viet Ha Pham Nhu

Keyword(s):

Comparative Analysis ◽

Fuel Assembly ◽

Spent Nuclear Fuel ◽

Minor Actinide ◽

Minor Actinides ◽

Spent Fuel ◽

Burnable Poison ◽

Uranium Fuel ◽

Enriched Uranium ◽

Actinide Transmutation

The feasibility of transmutation of minor actinides recycled from the spent nuclear fuel in the VVER-1000 LEU (low enriched uranium) fuel assembly as burnable poison was examined in our previous study. However, only the minor actinide vector of the VVER-440 spent fuel was considered. In this paper, various vectors of minor actinides recycled from the spent fuel of VVER-440, PWR-1000, and VVER-1000 reactors were therefore employed in the analysis in order to investigate the minor actinide transmutation efficiency of the VVER-1000 fuel assembly with different minor actinide compositions. The comparative analysis was conducted for the two models of minor actinide loading in the LEU fuel assembly: homogeneous mixing in the UGD (Uranium-Gadolinium) pins and coating a thin layer to the UGD pins. The parameters to be analysed and compared include the reactivity of the LEU fuel assembly versus burnup and the transmutation of minor actinide nuclides when loading different minor actinide vectors into the LEU fuel assembly.

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