Reactor

FIELD: power industry.

SUBSTANCE: invention is designed for being used as single-block marine high-duty nuclear power plants with high unit power, which operate in varying load mode. Liquid-metal carrier is used in the proposed reactor. Besides, different arrangement patterns of heat transfer to liquid of the second circuit are located inside the reactor housing. The proposed device includes an integral active zone, a nuclear reaction control system and a protection system, steam generators and heat exchangers, heat carrier pumping pumps, and biological protection. At that, an electromagnetic pump is installed in the heat carrier circuit when heat is being transferred in steam generator; the above pump is coaxially attached to lower part of vertically located steam generator, and in the heat carrier circuit when heat carrier is being transferred in heat exchanger the provision is made for its connection to lower part of heat exchanger by means of a pipeline and location that is parallel to vertically located heat exchanger. Heat carrier flow is arranged in upward direction through active reactor zone.

EFFECT: optimisation of heat exchange in mode of varying loads and obtaining optimum weight and dimensional parameters of nuclear power plants as a whole, being the part of the ship.

1 dwg

 

The invention relates to heat-exchange technique and is intended for use as a monoblock ship high-stressed nuclear power units (NPU) of large capacity.

Known nuclear power plant, containing integral nuclear reactor with case and cover, at least three circuits of circulation heat exchangers installed between the paths for heat transfer, the pressure compensator of the first circuit and the piping for supplying and discharging the coolant from the heat exchanger and the first and second paths, and the housing of the heat exchanger of the second and third circuits installed on the lid of the reactor, in which you have at least two holes for pipes for supplying and discharging coolant to the heat exchanger and the first and second paths, and the pipe for supplying coolant to the heat exchanger and the first and second paths communicated with the space below the heat exchange surface of the heat exchanger the second and third circuits, and the exhaust tube with the space above this heat exchange surface /bald E.N. and other Nuclear power plant. Patent RU No. 2056651. G21C 1/00. Priority - 20.07.92. Publ. in Bulletin of inventions No. 20. 1995. - analog/.

The disadvantage of this technical solution is a great length and considerable massag britnye the path parameters Teploobmennik liquids; large losses of heat transfer from the active zone of the nuclear reactor to obtain dry saturated steam in the third circuit, that is unreasonably low efficiency in the conversion of heat energy into electrical energy; the relatively low reliability of the whole structure due to the presence of additional circuit, as the technology of manufacturing and installation of such devices is always associated with a completely new and very complex issues to their resolution in connection with the fact that each subsequent reactor, even from the same series, always has refinements related because of the long time the design of such devices, manufacturing, installation, debugging, training service staff, new achievements in this field.

Known nuclear reactor with natural circulation of the heat carrier containing the active zone, placed in the shell, inside of which is formed by lifting the plot of the path of the coolant, and in the space between the shell and the reactor vessel and lowering the section of the path of the coolant cold reactor located below the upper end of the shell, and the lifting and lowering stations are additionally connected by a line, the input and the output of which is positioned below the fluid level cold reactor in the lifting and lowering stations, respectively, and the line in its upper elevation, p is polojennaya above operational level, attached to the system fill and drain line / PAC NN. and other Nuclear reactor with natural circulation of the coolant. Patent RU No. 1823009. G21C 1/00. Priority - 04.07.90. Publ. in Bulletin of inventions No. 23. 1993. - prototype/.

The disadvantage of this technical solution is that a reactor of this type is characterized by low efficiency of conversion obtained in the active zone of heat and electricity generation at the output of the NPU. The nuclear industry States that produce pressure vessels, reactors with natural circulation of the coolant of the first and, as a consequence, the subsequent circuits to generate electricity in large quantities in a nominal mode of operation produces. Experiment with natural circulation on ChNPP unit 4 is led to the melt and subsequent explosion, that is, this method of operation for large volumes of passing coolant through the core of a nuclear reactor is characterized by low reliability of the whole structure as a whole.

The technical result of the invention to increase the service life of the NPP at the expense of increasing the reliability and improving the process of heat transfer while reducing weight and size parameters of the reactor as a whole.

This technical result is achieved by the fact that the reactor, mainly monoblock type for marine NPP and with the use of liquid metal coolant and working in the regime of variable loads, comprising a housing, inside of which there are various design schemes for the transfer of heat to the fluid of the second integrated circuit 1 active zone and a corresponding control system and protection system (CPS) nuclear reaction, steam generators and heat exchangers, pumps for pumping Teploobmennik liquids, biological protection, and in circuit with the coolant, heat transfer in the steam generator, coaxially mounted electromagnetic pump is connected to a lower part of a vertical steam generator, and in circuit with the coolant, heat transfer in the heat exchanger, is connected with the lower part of the heat exchanger through the pipe and is parallel to the vertically positioned heat exchanger, and the movement coolant through the integral reactor core arranged from bottom to top.

Summary of the invention illustrated by the drawing, which shows a longitudinal section of a reactor design.

The reactor, mainly monoblock type for marine NPP using liquid metal coolant and working in the regime of variable loads, includes a housing 0 with lid 1 in which there are various design schemes for the transfer of heat to the fluid of the secondary circuit, integral active zone 2 and the corresponding control system and protection system (CPS) 3 nuclear reaction with boroviki rods 4, the heat exchangers 5 and the steam generator 6, is connected to the steam generator 6 electromagnetic pump 7 for pumping liquid metal coolant through the channel 8 of the first circuit, biological defense 9, covering all internal equipment of the reactor. For heat removal in the steam generator 6 is supplied through the pipe 10 feed water when running at 30% power reactor, 100% operation mode is an additional makeup water through the pipe 11. The output of superheated steam is organized through the pipe 12. For reliable operation of the steam generator 6 and the pump 7 is used the equipment to be placed in the vessel 13. The heat exchanger 5 has a pipe 14 of the feed water pipe 15 supply make-up water, the outlet 16 of the output of superheated steam, sealing unit 17 of the input cable of the pump (not shown), and for the safe passage of the aforementioned paths through the flow channels for liquid metal coolant allocated capacity 18. The path of the coolant from the heat exchanger 5 to a pump (not shown) through pipe 19, and the supply of feed water to the heat exchanger through pipe 20. The movement of the liquid metal coolant downstream of the pump (not shown) is provided on the channel 21 with the organization tract bottom-up relative to integralnoi active zone 2 of the reactor.

The reactor operates as follows.

Movement Teploobmennik liquids arranged in counterflow circuit diagram as in the heat exchanger 5 and the generator 6, and an electromagnetic pump 7 of the steam generator 6 is connected with a side of chilled coolant and dangle him upside-down, and the electromagnetic pump (not shown)located parallel to the heat exchanger 5, taking chilled coolant, dangle from the bottom-up with rotation to the opposite direction in a vertical channel and subsequent supply channel 21 and integral active zone 2 bottom-up. Regulation of feedwater is achieved by the design of the steam generator 6 and an automatic valve of the heat exchanger 5 at a corresponding reactor power.

The application of the proposed reactor in a ship NPU will allow effective heat transfer in the mode variable loads and get the best weight / size parameters of the NPP as a whole, to ensure reliability for the estimated resource use in the composition of all equipment as submarine and surface ships.

The reactor mainly monoblock type for marine NPP using liquid metal coolant and working in the regime of variable loads, comprising a housing within which are located the hypoxia design scheme organization transferring the heat to the fluid of the secondary circuit, integral active zone and a corresponding control system and protection system (CPS) nuclear reaction, steam generators and heat exchangers, pumps for pumping Teploobmennik liquids, biological protection, characterized in that in the circuit with the coolant, heat transfer in the steam generator coaxially mounted electromagnetic pump is connected to a lower part of a vertical steam generator, and in circuit with the coolant, heat transfer in the heat exchanger, is connected with the lower part of the heat exchanger through the pipe and is parallel to the vertically positioned heat exchanger, while the coolant flows through the integral reactor core is organized bottom-up.



 

Same patents:

FIELD: power industry.

SUBSTANCE: invention is related to nuclear reactor with pressure water with active zone based on coated particles, which includes heterogeneous fuel assemblies arranged in backfill in distributed radial zones adjacent to inlet (5) and outlet (12) headers, with possibility of forming a heat carrier cross flow and with possibility of removing waste fuel assemblies, moving the rest fuel assemblies and additional loading of fresh fuel assemblies; at that, fresh fuel assemblies being arranged additionally without any burnable absorber. Method for implementation of operation of nuclear reactor with pressure water with active zone based on coated particles involves simultaneous arrangement in active zone of heterogeneous fuel assemblies, formation of cross flow and volumetric steam quantity of heat carrier, removal of waste fuel assemblies, and movement of the rest fuel assemblies and additional loading of fresh fuel assemblies. Besides, volumetric steam quantity of not less than 10% is formed in fresh fuel assemblies by controlling the heat carrier boiling intensity.

EFFECT: possible compensation of high margin of reactivity owing to changing the density of heat carrier - retarder during boiling process.

10 cl, 3 dwg

FIELD: process engineering.

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FIELD: instrument making.

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EFFECT: higher accuracy.

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Reactor plant // 2473984

FIELD: power engineering.

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EFFECT: prevention of gas and admixtures ingress into a coolant flow going towards an impeller, lower stresses in elements of an MCP body; increased stiffness of MCP cantilever part, reduced spread of coolant flow parameters upstream an impeller, reduced activation of elements of an MCP rotating assembly.

4 dwg

FIELD: power engineering.

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FIELD: physics, nuclear.

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FIELD: power industry.

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FIELD: power industry.

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FIELD: power engineering.

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Heat exchange unit // 2457415

FIELD: power industry.

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FIELD: power industry.

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FIELD: power engineering.

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5 cl, 4 dwg

FIELD: power engineering.

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EFFECT: reduced dimensions and weight of a shell-and-tube evaporator.

1 dwg

FIELD: power engineering.

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EFFECT: unification and reduction of heat exchanger dimensions.

4 cl, 3 dwg

Heat exchanger // 2451875

FIELD: power engineering.

SUBSTANCE: heat exchanger comprises helical elements from pipes installed in gaps between coils of each other. At the same time in each coil there are two straight and two rounded sections. Identical sections are located oppositely to each other. Each helical element comprises at least three straight sections, which are equidistant near adjacent elements. Axes of all elements in a heat exchanger cross in one point, which is simultaneously installed on the heat exchanger axis. Besides, any point at the axis of the heat exchanger is also a centre of a polygon, on a contour of which there are centres of pipes in any cross section of the heat exchanger via the specified point in the zone of straight sections of helical elements. Straight sections near adjacent helical elements may have different length. Opposite rounded sections of helical elements may be arranged with various radii, which monotonously alternate in coils, besides, the same alternation is arranged near adjacent helical elements.

EFFECT: compactness of a heat exchanger, especially in an area of location of straight sections, and also possibility to install a heat exchanger in cavities with a polygonal cross section, both permanent and alternating in height.

8 dwg

Heat exchanger // 2437047

FIELD: power industry.

SUBSTANCE: heat exchanger contains housing having external and internal cylindrical walls connected to each other by means of radial partitions forming through-type chambers with formation of continuous circulation circuit, heat exchange plates located inside the chambers and end covers one of which has an inlet opening and the other one has an outlet opening. Internal wall of the housing is made in the form of central insert with heat exchange element located in it; inlet opening is located coaxially to central insert. Radial partitions and heat exchange plates are fixed by means of inner ends in longitudinal slots made on external surface of central insert, and their outer ends are bent along circular arc and enclosed in the housing; at that, housing is equipped with heat exchange jacket. Radial partitions and heat exchange plates are equipped with longitudinal expansion joints.

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2 cl, 5 dwg

FIELD: heat power engineering.

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EFFECT: improved reliability.

15 cl, 6 dwg

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