Potentialities of the fast spectrum molten salt reactor concept: REBUS-3700

Thermodynamic evaluation of the NaCl–MgCl2–UCl3–PuCl3 system

“…In the REBUS-3700 concept [1] NaCl serves as a matrix of the fuel, whereas PuCl 3 is the fissile material and 238 UCl 3 is the fertile material. As a breeder design it produces more fissile material than it consumes.…”

“…Recently, Mourogov and Bokov [1] proposed the fast breeder molten salt reactor REBUS-3700 based on a UPu cycle, where U and Pu are present in the form of trichlorides dissolved in a matrix of liquid NaCl. In general the chlorides have higher vapor pressures and lower thermodynamic stability at high temperatures compared to fluorides, which are generally considered for molten salt reactor applications [2], but on the other hand, they are less aggressive against the structure materials and their melting points are lower.…”

Thermodynamic properties and phase diagrams of fluoride salts for nuclear applications

“…Therefore compounds like NaF, KF, RbF or CaF 2 can be considered as part of the fuel matrix. Moreover there are some 'fast' MSR concepts [6] that are based on the chloride matrix ( 35 Cl: s fast ¼ 0:0011 barn, whereas s thermal ¼ 43:63 barn).…”

Why the molten salt fast reactor (MSFR) is the “best” Gen IV reactor

“…The 27-day half-life 233 Pa then decays to generate fresh fissile ( 233 U) that is transferred back to the fuel salt stream. In principle, it can operate indefinitely with no fuel other than makeup thorium if it is close coupled to a chemical reprocessing system capable of simultaneously transferring the fissile generated in its blanket salt to the core and preventing excessive fission product (FP) neutron poison 11 build up without excessive loss of thorium and 7 Li. However, ORNL's calculations indicated that this configuration could not achieve break-even fissile regeneration (isobreeding) with a core tank large enough to generate a worthwhile amount of power (>100 MW e ) unless thorium was also present in the fuel-side salt, which, in turn, would raise seemingly insuperable "reprocessing issues" due to its chemical similarities to rare earth element (REE) FP neutron poisons.…”

“…6) became the EURATOM Consortium's (EVOL's) "reference" MSR. 19 While most of the previous studies of fast-spectrum MSRs had assumed a chloride 20 -based solvent salt in order to facilitate Pu breeding [11], fertile-free TRU burning, or U-supported TRU burning [12], EVOL's leadership assumed a somewhat less fast fluoride salt-based system in order to capitalize upon ORNL's extensive materials science and fuel salt chemistry experience [13].…”