Molten salt fast reactor High-temperature reactors

Furthermore, HEEP will consider several reactor concepts including water reactors such as PWR and PHWR for the lower temperature range, the very high temperature reactors (VHTR), fast breeder reactors (FBR) and molten-salt cooled reactors for the high temperature range, and super-critical water reactor (SCWR) capable of output temperatures up to around 625°C for the medium range of temperature. 

Liquid Salt Systems (Low Pressure) Heat Transport Systems (Reactor to H2 Plant) Advanced High-Temperature Reactor (Solid Fuel) Liquid-Sait-Cooied Fast Reactor (Solid Fuel) Molten Salt Reactor (Liquid Fuel)... 

LWR, light water reactor HTR, high-temperature reactor LMFR, liquid metal fast leat r SCWR, supercritical water cooled reactor, VHTR, very-high ten4)CTature reactor SFR sodium-cooled fast reactor GFR, gas fast reactor LFR, lead-cooled fast reactor Af5/ , molten salt reacts. 

In 2002, the Generation IV International Forum selected six systems as Generation IV technologies very-high-temperature reactors (VHTRs), supercritical water-cooled reactors (SCWRs), gas-cooled fast reactors (GFRs), lead-cooled fast reactors (LFRs), sodium-cooled fast reactors (SFRs), and molten salt-cooled reactors (MSRs). As shown in Table 12.1, the spectra of the operating conditions for the six selected types of reactors are versatile [1]. 

Table 1.3 summarizes the materials used for the principal services in pressurized-water and boiling-water reactors, the high-temperature gas-cooled reactor, fast reactors, and the molten-salt reactor, and indicates which materials are fixed in each reactor and which flow through it. 

As it was mentioned, boron carbide containing enriched elemental boron ( B 65 at%) can serve as the control rod material in fast breeder nuclear reactors. Because boron carbide is fabricated by reacting elemental boron with carbon and the elemental boron in turn is produced by electro-winning process, Jain et al. (2011) have carried out studies to explore the viability of a high-temperature molten salt electro-winning process for the large-scale production of °B isotopically enriched elemental boron. It was established that elemental boron powder with a purity of better than 95 wt% could be produced. 

The various high temperature concepts propose three coolants - molten salt Pb or Pb-Bi and gas. The fuel is nitride for fast spectrum concepts (BGR-300 (28) suggests the use of advanced porous fuel) and TRISO derivative for thermal or intermediate spectrum concepts. Two of the 5 concepts are reactors intended for operation in U-Th fuel cycle. 

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. 

Helium is the traditional high temperature, high pressure gas coolant. Liquid fluoride salts are a traditional high temperature, low pressure liquid coolant. The only other potential candidates are liquid metals, particularly molten lead or lead alloys for fast spectrum reactors. Because of their relatively low boiling points, traditional liquid metals such as sodium are not candidates for high temperature operations. 

With these goals in mind, some 100 experts evaluated 130 reactor concepts before GIF selected six reactor technologies for further R D. These include the gas-cooled fast reactor (GFR), lead-cooled fast reactor (LFR), molten salt reactor (MSR), supercritical water-cooled reactor (SCWR), sodium-cooled fast reactor (SFR), and very high temperature reactor (VHTR). 

Figure 10.1 2013 Generation-IV International Forum Roadmap—viability, performance, and demonstration phases. GFR, gas-cooled fast reactor LFR, lead-cooled fast reactor MSR, molten salt reactor SCWR, supercritical water reactor SFR, sodium-cooled fast reactor VHTR, very-high—temperature reactor.

Part One, which is completely dedicated to six Generation IV concepts (1) Gas-cooled Fast Reactor (GFR) or just High Temperature Reactor (HTR) (2) Very High Temperature Reactor (VHTR) (3) Sodium-cooled Fast Reactor (SFR) (4) Lead-cooled Fast Reactor (LFR) (5) Molten Salt Reactor (MSR) and (6) Supercritical Water-cooled Reactor (SCWR) and which is started with the official information from the Generation IV International Forum (GIF). 

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