Potential of transuranics transmutation in a thorium‐based chloride salt fast reactor

Abstract

A thorium-based chloride salt fast reactor (TCLFR) for transuranics (TRUs) transmutation is proposed to decrease radioactive nuclear waste. The TCLFR core uses two types of fuel: liquid nuclear fuel with TRUs and thorium being dissolved in chloride and solid transmutation rod with only TRUs fuel. The transmutation capability of TCLFR with a core power of 2500 MWth is investigated utilizing three different reactor core configurations, namely ThCore, GdCore, and TcCore, and compared to the standard Molten Chloride Fast Reactor (MCFR) while maintaining most of the geometric parameters. Important burnup parameters such as transmutation rate (TRE) and transmutation ratio (TRO) are extracted and analyzed. Besides, the neutron spectrum shift and the relevant safety parameters, including power peak factor, temperature coefficient of reactivity (TCR) and effective delayed neutron fraction (β eff ) are all explored. The results demonstrate that all the TCLFR cores can transmute TRUs effectively. TRUs have a high online refueling amount of TRUs in TcCore and GdCore due to their low conversion ratio (CR). The TRE in the TcCore and GdCore is 292.77 kg/GWth/year and 258.31 kg/GWth/year, respectively, which is significantly higher than the TRE in the MCFR, which is 171.21 kg/GWth/year. As a result of the production of U-233 compensates for the consumption of TRUs, the refueling amount of TRUs decreases, and the TRE in the ThCore is only 96.29 kg/GWth/year, which is approximately 44% lower than that in the MCFR.

On the Employment of a Chloride or Floride Salt Fuel System in Advanced Molten Salt Reactors, Part 2; Core Inventory, Fuel Burnup, and Salt Clean-Up System

“…There is a strong need for a comprehensive assessment of these parameters throughout the reactor lifetime since their evolution can significantly affect the safety margins of the reactor. Considering the importance of evaluation of the MSRs burnup and its reactor core-related parameters, various research studies have been conducted that belong to one of the following categories: all employing burnup as the main parameter; (i) burnup and core inventory calculations , (ii) burnup optimization [15,[22][23][24], (iii) salt clean-up systems [25][26][27][28][29], and, finally, (iv) waste transmutation [30][31][32][33][34].…”

“…This application has been developed in different projects and collaborations such as MOSART [37], MARS [38], and MIMOSA [39]. This feature can be achieved through two different approaches, (i) designing MSFRs in a way that can utilize spent nuclear fuel (SNF) as a fuel source and operate in a closed fuel cycle [31][32][33] and (ii) designing waste transmuter based on MSFR technology [30,34,38]. In addition to employing MSFR technology for the latter option, Advanced Liquid-Metal Reactors (ALMRs), Particle Bed Reactors (PBRs), accelerator transmutation of waste (ATW) systems, and accelerator-driven fast reactor concepts are other systems that have been suggested by different technology developers [40].…”

Transmutation of Transuranic Elements as Solid Coating in Molten Salt Reactor Fuel Channel

“…The primary issue in the SNF lies in the transuranic (TRU) elements, which consist of plutonium (Pu) and minor actinide (MA) isotopes [1]. Many TRU isotopes have a long half-life so that the time required for them to decay until the remaining radioactivity equals the reference value spans up to 130,000 years [2]. Most of the radioactivity would be in the form of alpha and beta radiation, which pose a risk only if ingested or inhaled.…”

“…As fission reaction results in short-lived fission products, transmutation through fission can assure the resulting radionuclides to be rapidly decays into stable nuclide. However, thermal-spectrum reactors also have advantage as neutron capture probability is larger in thermal energy region, although neutron capture reaction (n, γ) does not always result in short-lived radionuclides [2].…”

“…An alternative to this method is by using heterogeneous method, where the TRUs are separated from the fuel salt as a solid elements. Such heterogeneous configuration was studied in fast chloride MSR [2], but none has been studied in thermal fluoride. This research was performed as an initial assessment of the potential of TRU transmutation as a heterogeneous configuration in thermal MSR.…”