Sodium cooled fast reactors fuel cycles

Liquid salt cooled fast reactor. Liquid salt cooled fast reactors are similar in design (fuel, plant, etc.) to sodium cooled fast reactors, except they are designed to operate at higher temperatures and use Brayton power cycles. These reactors use fast reactor fuel cycles and may be breeder reactors. Only limited exploratory work [XXVI-8] has been conducted on such reactors thus, there are many uncertainties. 

With a purpose of probing a commercially feasible fast reactor system, a feasibility study on commercialized fast reactor cycle systems (FS) was initiated in 1999 (Aizawa, 2001). In the FS, survey studies were made to identify the most promising concept among various systems such as sodium-cooled fast reactors, gas-cooled fast reactors, heavy metal-cooled fast reactors (lead-cooled fast reactors and lead-bismuth cooled fast reactors), and water-cooled fast reactors with various fuels types such as oxide, nitride, and metal fuels. The FS concluded to select an advanced loop-type SFR with mixed oxide fuel named Japan sodium-cooled fast reactor (JSFR Kotake et al., 2005). 

BN-1200 is the latest generation of sodium-cooled fast reactors intended for serial constmction and transition to a closed fuel cycle nuclear power. Its fundamental engineering solutions rely on BN-600 and BN-800 experience, as far as sodium coolant... 

Bakanov, M.V., Nosov, Yu.V., Potapov, O.A., 2013. Operating experience with the BN-600 sodium-cooled fast reactor. In FRs and Related Fuel Cycles Safe Technology and Sustainable Scenarios (FRl 3). Proceedings from the International Conference on Fast Reactors and Related Fuel Cycles, vol. 2. Paris, France. 

Much, but not all of the fuel technology for the MSR exists. Most of the LFR fuel cycle exists because it uses the same basic technology that was developed for the sodium-cooled fast reactor. (The sodium-cooled fast reactor itself is not a candidate for H2 production because of the low boiling point of sodiiun.) However, the LFR technology has not been deployed on a commercial scale. The GFR fuel cycle technology is in a very early state of development (fuel form not yet defined). 

The SFR is a sodium-cooled fast-neutron-spectrum reactor designed primarily for the efficient management of actinides and conversion of fertile uranium in a closed fuel cycle. 

The fuel cycle concept of the RMWR is basically a closed cycle and is the same as for FBRs (sodium cooled fast breeder reactors). It has been confirmed that the high conversion ratio, more than 1.0 and the negative void reactivity coefficient can be achieved in the RMWR core under the multiple recycling of Pu including advanced fuel reprocessing schemes. 

Figure 2.5 SFR Molten sodium-cooled, fast neutron spectrum reactor with closed fuel cycle and outlet temperatures within 500—550°C (shown pool-type reactor with indirect steam turbine Rankine power cycle). 

T. Kaito, S. Ohtsuka, M. Inoue, Progress in the R D project on oxide dispersion strengthened and precipitation hardened ferritic steels for sodium cooled fast breeder reactor fuels, in International Conference GLOBAL 2007 Advanced Nuclear Fuel Cycles and Systems, September 9—13, 2007, Boise, Idaho, USA, 2007. 

M. Nakazaki, J. Taguchi et al., Development of Sodium-Immersed Self-Cooled Electromagnetic Pump , Proc. Int. Conf. on Fast Reactors and Related Fuel Cycles, (1991)P2-16... 

As it was already mentioned, the AHTR concept (Annex XXVI) brings together the technologies of HTGRs (high temperature fuel, gas turbine Brayton power cycle), molten salt reactors (liquid salt coolant that, in the AHTR case, contains no fuel) and fast sodium cooled reactors (no excess pressure in the primary circuit intermediate heat transport system). The AHTR uses forced circulation of the primary liquid salt coolant and its intermediate heat transport system is also based on liquid salt. 

The future of the Russian nuclear industry is expected to be a closed fuel cycle, powered by a combination of LWR and fast reactor technology. The critical element in the Russian strategy is the GEN-IV fast reactor technology, including sodium, Pb, and Pb—Bi-cooled reactors. The USSR and then Russia have experimented with all three of these technologies, including budding experimental and demonstration reactors, over the last half century. 

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