RU57040U1 - NUCLEAR REACTOR PLANT WITH FUEL-HEAT CARRIER IN THE FORM OF MELTS OF FLUORIDE SALTS - Google Patents

Abstract

The utility model relates to the field of nuclear energy, mainly to nuclear reactors with a heat-transfer fluid in the form of molten fluoride salts and water as the working fluid of a steam turbine plant. A nuclear reactor with fuel and coolant in the form of molten fluoride salts includes a liquid salt reactor (JLR) thermal neutrons, the first and intermediate circuits, the heat exchanger of the first - intermediate circuits, pipelines and the intermediate circuit circulation pump, the tube system of the steam generator, tanks for Lib fluoride salt melts first and intermediate circuits and apparatus for the purification of fluoride molten salt nuclear reaction products. Structurally, the installation is made of monoblock 1, in which the first and intermediate circuits and the heat exchanger of the steam generator are located directly in the ZhSR: The intermediate circuit is made in the form of channels in carbon block moderator 4 and cavity in the neutron reflector block 5; the heat exchanger of the first - intermediate circuits 7 is made in the form of channels built into the graphite blocks of the neutron moderator of the reactor core 2; the heat exchanger of the intermediate circuit-steam generator is made in the form of a cavity located in the neutron reflector 5; the tube system of the steam generator 10 is built into the blocks of graphite neutron reflector; in the active zone of the ZhSR 2 there is a channel for the inducer of mixing the molten salt of fuel, through which an inert gas is passed by means of gas blower 14; channel 6 of the inducer of mixing the molten salt of fuel is connected to a device for purifying inert gas from the gaseous and volatile products of nuclear reactions 13; As a moderator and neutron reflector, modified graphite of reactor purity of high thermal conductivity and heat resistance is used. The technical result of the developed installation is to reduce the radiation hazard, reduce the volume of fuel-coolant melt, reduce the size of equipment requiring additional biological protection, reduce energy costs to ensure the circulation of molten fluoride salts of the first and intermediate circuits

Description

The utility model relates to the field of nuclear energy, mainly to nuclear reactors with heat-transfer fluid in the form of molten fluoride salts and water as the working fluid of a steam turbine plant.

The closest in technical essence and the achieved result is a nuclear reactor installation (NRU) with a liquid salt reactor [“Synergetic fuel cycle with molten salt reactors” Furukawa K, Lekok A, Kato Y, Mitachi K. NUCLEAR TECHNOLOGY ABROAD, 1993, No. 5 pg. 13-19

The nuclear power reactor includes a thermal neutron liquid salt reactor (LCR), pipelines and a primary circuit circulation pump with molten fuel fluoride salts, a primary – intermediate circuit heat exchanger, pipelines and an intermediate circuit circulation pump with molten intermediate fluoride salts, an external steam generator with a pipe system, a tank for discharge of a melt of salts of fluorides of the intermediate circuit, a container for draining the melt of salts of fluorides of the first circuit and a device for cleaning the melt of salts of fluorides of the first circuit round from nuclear reaction products.

Structurally, the nuclear reactor consists of 3 blocks: a ZhSR block with a device for cleaning the molten fluoride salts of the primary circuit from nuclear reaction products, a heat exchanger unit of the first - intermediate circuits with a circulation pump, and an intermediate circuit heat exchanger block - a steam generator with a circulation pump.

YSSR YARU - consists of a core of a thermal neutron reactor, a molten salt of fuel fluoride - a primary coolant, a neutron moderator and a neutron reflector made of graphite.

The nuclear reactor consists of JSS and “remote units” of the first and intermediate circuits. The heat-transfer fluid in the form of melts of fluoride salts accumulates the heat energy released in the core, and through pipelines and a circulation pump of the primary circuit is sent to the heat exchanger of the first - intermediate circuit. From the heat exchanger, thermal energy is sent through pipelines and a circulation pump of the intermediate circuit to

intermediate circuit heat exchanger - steam generator.

The presence of “remote” units increases the volume of fuel-coolant, requires additional biological protection, increases the mass and volume of the installation, increases energy consumption during pumping of fuel and coolant and provides the necessary temperature conditions for pipelines.

The objective of the utility model is the development of a monoblock installation with a liquid salt reactor.

The technical result of the developed installation is to reduce the radiation hazard, reduce the volume of molten fuel-coolant, reduce the size of equipment requiring additional biological protection, reduce energy costs to ensure the circulation of molten fluoride salts of the first and intermediate circuits.

The technical result is achieved due to:

- monoblock design, in which the first and intermediate circuits and the heat exchanger-steam generator are located directly in the ZhSR;

- exclusions of active circulation of highly radioactive fuel fluoride melt;

- heat removal from the fuel melt due to the thermal conductivity of the graphite blocks of the moderator in the core, in which the heat exchanger of the circulating melt of the intermediate fluorides is integrated, and the thermal conductivity of the reflector graphite;

- elimination of branched pipelines of systems for the forced circulation of fluoride salt melts in the first and intermediate circuits and, consequently, a decrease in the mass of fluoride melts in the circuits.

The problem is solved as follows.

A reactor facility (NRU) with fuel and a coolant in the form of fluoride salt melts includes a thermal salt neutron salt reactor (LSR), a first and an intermediate circuit, a heat exchanger of the first - intermediate circuits, pipelines and an intermediate circuit circulation pump, a steam generator pipe system, and tanks for draining the melts salts of fluorides of the first and intermediate circuits and a device for cleaning the molten fluoride salts from nuclear reaction products. Structurally, the installation is made monoblock, in which the first and intermediate circuits and the heat exchanger of the steam generator are located directly in the ZhSR:

- the intermediate circuit is made in the form of channels in carbon-moderator blocks and cavities in the neutron reflector block;

- the heat exchanger of the first - intermediate circuits is made in the form of channels built into the blocks of graphite - the neutron moderator of the reactor core;

- the heat exchanger of the intermediate circuit - the steam generator is made in the form of a cavity located in the neutron reflector;

- the tube system of the steam generator is built into the blocks of graphite neutron reflector;

- in the active zone of the JCL there is a channel for the inducer of mixing the molten fuel salts, through which an inert gas is passed through gas blowing;

- the channel for stimulating the mixing of the molten salt of the fuel is connected to a device for purifying the inert gas from the gaseous and volatile products of nuclear reactions contained therein;

- as a moderator and reflector of neutrons use modified graphite reactor purity of high thermal conductivity and heat resistance.

The inventive NAR is structurally made in the form of a monoblock, including an active zone of the JSR, an intermediate circuit built into the graphite blocks of the neutron moderator of the core and the reflector, and an integrated steam generator located in the graphite blocks of the reflector.

The installation diagram is presented in figure 1, where:

- 1 - a monoblock of nuclear weapons with JSR on thermal neutrons;

- 2 - an active zone of JSR on thermal neutrons;

- 3 - molten salts of fuel fluorides;

- 4 - blocks of graphite moderator of neutrons in the core 2;

- 5 - graphite blocks of a neutron reflector;

- 6 - channel inducer of mixing the molten salts of fuel in the active zone by gas lift,

- 7 - the heat exchanger of the first - intermediate circuits, built into the graphite blocks of the moderator 4 of the active zone 2;

- 8 - molten salts of fluorides of the intermediate circuit;

- 9 - circulation pump for molten salts of fluorides of the intermediate circuit;

- 10 - pipe system of the built-in steam generator located in the cavity of the reflector 5;

- 11 - tank for draining the molten salts of fluorides of the intermediate circuit;

- 12 - a tank for draining the molten fluoride salts from the core;

- 13 - a device for cleaning circulating inert gas from gaseous and volatile products of nuclear reactions;

- 14 - gas blower.

The inventive monoblock YAR works as follows.

The melt of 3 salts of fuel fluorides, containing solutions of thorium-232 fluorides and fissile materials, is heated by the energy released during the fission of fuel nuclei by thermal neutrons in the core 2.

The intermediate circuit with a melt of 8 fluoride salts is made in the form of channels 7 located in graphite blocks 4 of a neutron moderator and a cavity 10 located in a reflector 5. Substitution of a part of graphite in the reactor core and in a neutron reflector by a melt of fluoride salts of an intermediate circuit, consisting of elements with a high inhibitory ability and small neutron absorption cross sections, practically does not change the nuclear physical parameters of the reactor. The melt of the fluoride salts of the intermediate circuit is circulated by means of circulation pumps 9, and the heat released in the reactor core 2 to the circulating melt 8 of fluoride salts of the intermediate circuit is carried out due to thermal conductivity through the walls of the graphite blocks of the moderator 4, in which the channels 7 of the heat exchanger of the first - intermediate circuit are located and also through the side graphite walls of the cavity of the reflector 5. The installation uses modified graphite with high thermal conductivity (~ 200 J / m C).

The heat exchanger of the intermediate circuit-steam generator is made in the form of a cavity located in the neutron reflector 5, in which the tube system 10 of the steam generator is integrated. Through the pipe system 10 of the steam generator, the working fluid of the steam turbine installation is pumped.

Mixing of the molten salt of fuel fluoride in the reactor core is carried out due to the gas lift effect when inert gas is supplied by gas blower 14 to the lower part of channel 6. Channel 6 is at the same time a compensator for the change in the volume of fuel-coolant with a change in temperature in the core 2. In addition, the pumped inert gas takes from the fuel melt 3 contained in

gases and volatile substances that are products of nuclear reactions in the core 2. The inert gas is removed from the trapped gases and volatile products of nuclear reactions in device 13, through which gas is pumped by gas blower 14.

As a result of the proposed solutions, the following is achieved:

1) higher radiation safety of a monoblock nuclear reactor due to the fact that highly radioactive fuel 3 is not removed outside the core 2, all the radioactive gaseous and volatile products of nuclear reactions formed in the core are removed when inert gas is circulated, which is cleaned in a special device 13 before it is fed into the blower 14, and the melt of 8 intermediate fluoride salts circulating through the active zone 2 is practically not activated, therefore, even with its leakage, no radiation of environmental pollution;

2) a decrease in the amount of fuel loaded due to the fact that nuclear fuel 3 is located only in the active zone 2 of the ZhSR and is absent in the pipelines of the primary circuit and the heat exchanger of the first and intermediate circuits due to their exclusion from the composition of the nuclear reactor (as compared with the nuclear reactor of the prototype for the proposed ZhSR at the same power, 1.5 times less nuclear fuel is required), which reduces the financial costs of the fuel component;

3) reducing the size and weight of the monoblock nuclear reactor due to the exclusion of distributed equipment from its composition — pipelines and a primary circuit circulation pump and a primary – intermediate circuit heat exchanger requiring location under biological protection, as well as intermediate circuit pipelines connecting the first – intermediate circuit heat exchanger and the steam generator 10, located in the remote blocks of the distributed layout of the YaR prototype;

4) reduction of energy consumption for the circulation of molten salts of fuel fluoride due to the fact that instead of intensive circulation of fuel 3 it is only mixed in the core 2 using a gas lift device 6, and the circulation of the molten salts of fluoride 8 of the intermediate circuit is carried out along much shorter paths in a compact monoblock scheme JSR 1, which is essentially a nuclear weapon;

5) providing additional security by eliminating the freezing of the pipelines of the intermediate circuit during reactor operation due to the composition of the salts of fluorides 8 of the intermediate circuit, which is always in a liquid state in the presence of fuel fluoride salts in the molten core 3.

Claims (1)

Nuclear reactor installation (NRU) with fuel and coolant in the form of fluoride salt melts, including a liquid salt reactor (LSR) using thermal neutrons, a first and an intermediate circuit, a heat exchanger of the first and intermediate circuits, pipelines and an intermediate circuit circulation pump, a steam generator pipe system, and tanks for discharge of molten fluoride salts of the first and intermediate circuits and a device for cleaning molten fluoride salts of nuclear reaction products, characterized in that the nuclear reactor is made monoblock, at The first and intermediate circuits and the heat exchanger of the intermediate circuit-steam generator are located directly in the LSR, the intermediate circuit is made in the form of channels located in the carbon-moderator blocks of the active zone of the LSR, and in the form of a cavity located in the neutron reflector block, the heat exchanger of the first - intermediate circuits is made in the form of channels built into the blocks of the graphite moderator of neutrons in the reactor core, the heat exchanger of the intermediate circuit-steam generator is made in the form of a cavity located in neutron suppressor, the tube system of the steam generator is built into the cavity of the intermediate circuit located in the graphite blocks of the neutron reflector, the channel for stimulating the mixing of the molten salt of fuel is built into the active zone of the LSR through which an inert gas is passed through the gas blower, the channel for stirring the mixing of the molten salt of fuel is connected to a cleaning device inert gas.