A nuclear reactor facility may include a reactor building, a reactor vessel housed within the reactor building, and an auxiliary cooling system integrated with the reactor building. The reactor building has a visible section above a ground level and a buried section below the ground level. The reactor vessel contains a fuel core and is housed within the buried section of the reactor building below the ground level. The auxiliary cooling system includes a plurality of ducts integrated with the reactor building and is configured to passively cool the reactor vessel via natural air circulation.

The present disclosure relates to reducing losses in the effective delayed neutron fraction during the operation of a reactor, making it possible to provide for a high efficiency of burning out of minor actinides, and also that of increasing the leak-tight integrity of the primary circuit and the reliability of the reactor. The above-mentioned technical result is achieved in an integral molten salt fast reactor with a circulating fuel composition, comprising a vessel with inlet and outlet secondary circuit pipelines and a connection pipe for initial filling and replenishment with molten salt coolant, heat exchangers of the primary/secondary circuit, a side reflector, an upper reflector and a lower reflector, a core with a shell, and a main circulation pipe, wherein the side reflector is made of sections between which the heat exchangers of the primary/secondary circuit are arranged such that they lie flush against the shell of the core.

The present disclosure relates to reducing losses in the effective delayed neutron fraction during the operation of a reactor, making it possible to provide for a high efficiency of burning out of minor actinides, and also that of increasing the leak-tight integrity of the primary circuit and the reliability of the reactor. The above-mentioned technical result is achieved in an integral molten salt fast reactor with a circulating fuel composition, comprising a vessel with inlet and outlet secondary circuit pipelines and a connection pipe for initial filling and replenishment with molten salt coolant, heat exchangers of the primary/secondary circuit, a side reflector, an upper reflector and a lower reflector, a core with a shell, and a main circulation pipe, wherein the side reflector is made of sections between which the heat exchangers of the primary/secondary circuit are arranged such that they lie flush against the shell of the core.

A ferritic alloy comprising in weight %: C: 0.01-0.1; N: 0.001-0.1; O: ≦0.2; B: ≦0.01; Cr: 9.0-13.0; Al: 2.5-8.0; Si: ≦0.5; Mn: ≦0.4; Y: ≦2.2; Sc+Ce+La: ≦0.2; Mo+W: ≦4.0; Ti: ≦1.7; Zr: ≦3.3; Nb: ≦3.3; V: ≦1.8; Hf+Ta+Th: ≦6.5; the balance being Fe and unavoidable impurities, wherein, the amounts of Ti+Zr+Nb+V+Hf+Ta+Th and C, N and O are balanced such that:

[00001]$\frac{\begin{array}{c}\mathrm{at}.Math..Math.\%.Math..Math.\mathrm{Ti}+\mathrm{at}.Math..Math.\%.Math..Math.\mathrm{Zr}+\mathrm{at}.Math..Math.\%.Math..Math.\mathrm{Nb}+\mathrm{at}.Math..Math.\%.Math..Math.V+\\ \mathrm{at}.Math..Math.\%.Math..Math.\mathrm{Hf}+\mathrm{at}.Math..Math.\%.Math..Math.\mathrm{Ta}+\mathrm{at}.Math..Math.\%.Math..Math.\mathrm{Th}-x*\mathrm{at}.Math..Math.\%.Math..Math.O-\mathrm{at}.Math..Math.\%.Math..Math.N\end{array}}{}$

Configurations of molten fuel salt reactors are described that include an auxiliary cooling system which shared part of the primary coolant loop but allows for passive cooling of decay heat from the reactor. Furthermore, different pump configurations for circulating molten fuel through the reactor core and one or more in vessel heat exchangers are described.

The patent discloses method and control system for gas injection into the coolant of a nuclear reactor plant. The method includes the following steps: gas to be injected into the coolant is supplied from the gas system to the above-coolant space; gas is injected into the gas system from the above-coolant space. Technical result: prevention of reuse of contaminated gas.

The patent discloses method and control system for gas injection into the coolant of a nuclear reactor plant. The method includes the following steps: gas to be injected into the coolant is supplied from the gas system to the above-coolant space; gas is injected into the gas system from the above-coolant space. Technical result: prevention of reuse of contaminated gas.

This disclosure describes nuclear fuel salts usable in certain molten salt reactor designs and related systems and methods. Binary, ternary and quaternary chloride fuel salts of uranium, as well as other fissionable elements, are described. In addition, fuel salts of UCl.sub.xF.sub.y are disclosed as well as bromide fuel salts. This disclosure also presents methods and systems for manufacturing such fuel salts, for creating salts that reduce corrosion of the reactor components and for creating fuel salts that are not suitable for weapons applications.

This disclosure describes nuclear fuel salts usable in certain molten salt reactor designs and related systems and methods. Binary, ternary and quaternary chloride fuel salts of uranium, as well as other fissionable elements, are described. In addition, fuel salts of UCl.sub.xF.sub.y are disclosed as well as bromide fuel salts. This disclosure also presents methods and systems for manufacturing such fuel salts, for creating salts that reduce corrosion of the reactor components and for creating fuel salts that are not suitable for weapons applications.

Configurations of molten fuel salt reactors are described that utilize neutron-reflecting coolants or a combination of primary salt coolants and secondary neutron-reflecting coolants. Further configurations are described that circulate liquid neutron-reflecting material around an reactor core to control the neutronics of the reactor. Furthermore, configurations which use the circulating neutron-reflecting material to actively cool the containment vessel are also described.