Molten-salt reactor safety

Gat, U. et al. 1997. Molten Salt Reactors—Safety Options Galore. In Proceedings of an International ANS Topical Meeting on Advanced Reactor Safety, Orlando, FL. 

Because the reactor can be designed with very little excess reactivity in the core and the molten salt has very good heat transport characteristics, the potential for achieving passive safety objectives also exists. The fact that (1) the molten-salt reactor is a low pressure system, and (2) the coolant is very chemically stable and does not react with air or water also support the passive safety characteristics of this concept. 

XXX-26] SHIMAZXU, Y, Safety aspects on depressurization accident of a molten-salt reactor, ICAPP 03 (Proc. Int. Conf, Cordoba, Spain, 2003). 

Jiao, X., Wang, K., He, Z., Chen, K., 2015. Core safety discussion under station blackout ATWS accident of solid fuel molten salt reactor. Nuclear Techniques 38. 

Wei, Q., Mei, L., Zhai, Z., Wei, G., Chen, J., Cai, X., 2014. Preliminary study on safety characteristics of molten salt reactor. Atomic Energy Science and Technology 48. 

Zhang, D., Qiu, S., Su, G.H., 2009a. Development of a safety analysis code for molten salt reactors. Nuclear Engineering and Design 239, 2778—2785. 

Molten salt reactor (MSR) safety (Class L) No possibility of fuel melt low fissile inventory ... 

Molten Salt Reactor (MSR). The MSR [3] uses a liquid molten-fluoride salt as fuel and coolant. The uranium or plutonium fuel is dissolved in the molten salt. Two test reactors were built. In the 1950s, the Aircraft Reactor Experiment operated normally with molten salt exit temperatures of 815 C with peak operating temperatures up to 860 C and very low primary system pressures. Work continued on MSR technology for power applications until 1976. The reactor can be built in large sizes with passive safety systems. 

The AHTR appears to have excellent safety attributes. The combined thermal capacity of the graphite core and the molten salt coolant pool offer a large time buffer to reactor transients. The effective transfer of heat to the reactor vessel increases the effectiveness of the RVACS and DRAGS to remove decay heat, and the excellent fission product retention characteristic of molten salt provides an extra barrier to radioactive releases. The low-pressure, chemically nonreactive coolant also greatly reduces the potential for overpressurization of the reactor containment building and provides an important additional barrier for fission product release. The most important design and safety issue with the AHTR may be the performance and reliability of the thermal blanket system, which must maintain the vessel within an acceptable temperature range. 

Improved decay heat removal. Improved heat transfer by natural circulation of the molten salt allows the design of larger reactors with passive safety (see Sect. 3.3). 

If the AHTR is used to produce hydrogen, a key issue is the coupling of the two plants via the intermediate heat transport loop. The intermediate heat transfer system has two sets of safety-related functional requirements (1) protect the reactor and chemical plant from transients and accidents in either facility and (2) protect the reactor and chemical plant from transients and accidents within the intermediate heat transfer system. Molten salts may offer major safety advantages compared to helium for this application. 

Brovchenkao, M. 2012. Preliminary Safety Calculations to Improve the Design of Molten Salt Fast Reactor. In PHYSOR 2011, BCnoxville, TN. 

Explosions In the Molten Salt/Water System, Proceedings of the International Meeting on Thermal Reactor Safety. Chicago, IL,... 

The BGR-300 is a small tank-type reactor with the secondary vessel acting as a safety system. The BGR-300 has a three-region core profiled by the fissile material content and effective density. A molten salt reflector plays the role of an in-vessel radiation shield. The reactor core uses a porous matrix fuel in the form of quasi-homogeneous heat generating blocks with cross-circulated coolant. 

The balance of plant is assigned no nuclear safety function, and passive load following is achieved via reactivity feedbacks in response to heat demand communicated only by means of the molten salt intermediate loop. These two features could help totally decouple reactor safety performance from equipment failures and plant operator or plant maintenance personnel mistakes in the balance of plant. 

The reactor is a low pressure vessel filled with a low chemical potential coolant - explosions and fire hazards are low for the reactor itself The chemical plant, where explosive chemicals are handled, and industrial hazards exist is decoupled from the reactor by distance and by the molten salt intermediate heat transport circuit operating at ambient pressure since the reactor can remain within a safe operating regime while innately adjusting its power production to any heat demand communicated through the intermediate circuit, - intended or spurious -events in the industrial chemical plant would not influence reactor safety performance. 

SAMOFAR Safety assessment of MOlten salt fast reactor... 

SMART-MSFR Safety of Minor Actinides Recycling and Transmuting in Molten Salt Fast Reactor... 

Brovchenko, M., et al., 2012. Preliminary safety calculations to improve the design of molten salt fast reactor. In Proceedings of the International Conference PHYSOR 2012 Advances in Reactor Physics Linking Research, Industry, and Education, Knoxville, Tennessee, USA. 

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