CN114543556A

CN114543556A - U-shaped double-wall heat transfer pipe direct-current steam generator

Info

Publication number: CN114543556A
Application number: CN202111621966.3A
Authority: CN
Inventors: 张巍; 施慧烈; 罗垚; 王聪; 李净松; 王明伍
Original assignee: Research Institute of Nuclear Power Operation; China Nuclear Power Operation Technology Corp Ltd
Current assignee: Research Institute of Nuclear Power Operation; China Nuclear Power Operation Technology Corp Ltd
Priority date: 2021-12-28
Filing date: 2021-12-28
Publication date: 2022-05-27

Abstract

The invention particularly relates to a U-shaped double-wall heat transfer pipe direct-current steam generator which comprises a steam end enclosure, a steam pipe plate, a steam connecting pipe, a pipe bundle supporting component and a barrel (1), wherein the lower end of the steam end enclosure is connected with the upper end of the steam pipe plate, the steam connecting pipe is connected onto the steam end enclosure, the lower end of the steam pipe plate is connected with the barrel (1) to form a pipe bundle accommodating space (4), the pipe bundle is arranged in the pipe bundle accommodating space (4), the pipe bundle is coiled by a plurality of U-shaped double-wall heat transfer pipes (2), the U-shaped double-wall heat transfer pipes (2) are supported by the pipe bundle supporting component, the pipe ends of the pipe bundle are connected with the steam pipe plate, and the barrel (1) is provided with a shell pass inlet window (3). The U-shaped double-wall heat transfer pipe direct-current steam generator has high safety and reliability.

Description

U-shaped double-wall heat transfer pipe direct-current steam generator

Technical Field

The invention relates to the technical field of double-wall pipe heat exchange equipment, in particular to a U-shaped double-wall heat transfer pipe direct-current steam generator suitable for a liquid metal reactor.

Background

The supercritical carbon dioxide Brayton cycle has the advantages of high efficiency, low medium cost, compact and high structure, easy miniaturization and the like, and is particularly suitable for operation in a medium-high temperature range; therefore, the reactor is more suitable for a fourth-generation reactor power system which takes liquid metal as a coolant, such as a lead-based fast reactor like a lead-bismuth fast reactor, a sodium-cooled fast reactor and the like.

In recent years, the research on the power system of sodium-SCO 2, lead bismuth-SCO 2 and lead-SCO 2 is increasing. Liquid metal reactors typically employ a pool reactor configuration and the steam generators are typically located within the reactor pool. Since the SCO2 side is operated at a higher pressure and the liquid metal side is typically operated at a lower or higher pressure, steam generator reliability requirements are extremely high, otherwise, once high pressure CO2 leaks into the stack, the high pressure CO will cause damage to the stack internals and equipment, and in severe cases, even the stack vessel, resulting in radioactive material leakage.

At present, a steam generator for an SCO2 circulating system is mainly a compact printed circuit board type steam generator, the steam generator is compact in structure and large in heat transfer area in unit volume, the efficient heat transfer requirement of SCO2 can be effectively met, the integrity of a pressure-bearing boundary cannot be effectively solved, and the welding seams and the like of related sealing interfaces of the steam generator also have failure risks under the conditions of high temperature, corrosion and the like.

Disclosure of Invention

In view of the above, it is necessary to provide a U-shaped double-wall heat transfer tube once-through steam generator, which has high safety and reliability, in order to solve the problem of operational risk and accident caused by the breakage of the heat transfer tubes of the steam generator of the existing liquid metal reactor.

In order to achieve the above purpose, the invention provides the following technical scheme:

a U-shaped double-wall heat transfer pipe direct-current steam generator comprises a steam seal head, a steam pipe plate, a steam connecting pipe, a pipe bundle supporting component and a barrel body; the steam seal head lower extreme is connected with steam tube sheet upper end, connect the steam takeover on the steam seal head, steam tube sheet lower extreme and barrel are connected and are formed tube bank accommodation space, set up the tube bank in the tube bank accommodation space, the tube bank is coiled by a plurality of U type double-walled heat transfer pipes and is formed, support by tube bank supporting component between the U type double-walled heat transfer pipe, the pipe end and the steam tube sheet of tube bank are connected, the barrel is equipped with shell side import window.

The structure of the U-shaped double-wall heat transfer pipe direct-flow steam generator is similar to that of the traditional U-shaped single-wall heat transfer pipe direct-flow steam generator, and the flow channels of media on two sides of the steam generator are constructed by a cylinder, an end enclosure, a pipe bundle, a pipe plate, a connecting pipe, a pipe bundle supporting structure and the like. The direct current steam generator with U-shaped double-wall heat transfer tubes of the invention is mainly different from the direct current steam generator with traditional U-shaped single-wall heat transfer tubes in that: the direct-current steam generator with the U-shaped double-wall heat transfer pipe adopts the U-shaped double-wall heat transfer pipe as a main heat transfer unit, so that the reliability of the steam generator is improved; the U-shaped double-wall heat transfer pipe direct-current steam generator is arranged in a liquid metal reactor vessel, and a cylinder shell pass of the steam generator is not provided with an inlet and outlet connecting pipe, but is provided with an inlet and outlet window at a position corresponding to the cylinder shell pass according to requirements.

In one embodiment, the steam tube plate is a single tube plate, the steam tube plate comprises a tube plate, and the inner tube and the outer tube of the U-shaped double-wall heat transfer tube are welded with the tube plate.

In one embodiment, the steam tube plate is a double tube plate, the steam tube plate comprises an upper tube plate and a lower tube plate, the inner tube of the U-shaped double-wall heat transfer tube is welded with the upper tube plate, and the outer tube of the U-shaped double-wall heat transfer tube is welded with the lower tube plate; an inert gas containing chamber is formed between the upper tube plate and the lower tube plate, and inert gas is filled in the inert gas containing chamber; the filling pressure is less than the medium pressure of an inner pipe of the U-shaped double-wall heat transfer pipe and greater than the medium pressure of an outer pipe of the U-shaped double-wall heat transfer pipe; the breakage and leakage of the inner pipe and the outer pipe of the U-shaped double-wall heat transfer pipe can be found in time by monitoring the pressure of the inert gas containing chamber, and if the pressure of the inert gas containing chamber is reduced, the leakage of the outer pipe of the U-shaped double-wall heat transfer pipe is detected; if the inert gas containment chamber pressure rises, the inner tube, which is a U-shaped double-walled heat transfer tube, leaks.

Further, the steam connection pipe comprises a steam inlet connection pipe and a steam outlet connection pipe.

In one embodiment, the steam seal head is split and comprises a steam inlet seal head and a steam outlet seal head, the steam inlet seal head is connected with a steam inlet connecting pipe, and the steam outlet seal head is connected with a steam outlet connecting pipe.

In one embodiment, the steam seal head is integrated, a partition plate is arranged in the middle of the steam seal head to form a steam inlet chamber and a steam outlet chamber, the steam inlet chamber is connected with a steam inlet connecting pipe, and the steam outlet chamber is connected with a steam outlet connecting pipe.

Further, the U-shaped double-wall heat transfer pipe direct-current steam generator is positioned in the liquid metal reactor vessel, and a steam pipe plate of the U-shaped double-wall heat transfer pipe direct-current steam generator is connected with a top cover of the liquid metal reactor vessel in a sealing mode to form a shell side closed space.

Further, the steam tube plate of the U-shaped double-wall heat transfer tube direct-current steam generator is connected with the flange of the liquid metal reactor vessel top cover in a sealing mode or in a welding and sealing mode.

Furthermore, the shell side inlet window is arranged on the side or the lower part of the cylinder body.

In one embodiment, the shell-side inlet window is a one-piece aperture window.

In one embodiment, the access window is a porous window, and the shape of the holes of the porous window is circular, elliptic cylindrical or rectangular. The pattern of the holes of the porous window is not limited to that shown in fig. 7 to 9, but may be kidney-shaped, diamond-shaped, regular hexagon, etc.

Further, the U-shaped double-wall heat transfer pipe comprises a straight pipe and an arc pipe, two ends of the arc pipe are respectively connected with a straight pipe, and the straight pipe and the arc pipe are integrally formed.

Further, the arc-shaped pipe is a semicircular pipe, a semicircular pipe with a straight section, a semielliptical pipe or a semielliptical pipe with a straight section; the turning arc of the semi-elliptic pipe with the straight section is an arc, an elliptic arc or a nonstandard lofting smooth curve.

Further, the U-shaped double-walled heat transfer pipe is circumferentially arranged or radially arranged.

In one embodiment, the inner pipe and the outer pipe of the U-shaped double-wall heat transfer pipe are tightly attached.

In one embodiment, the inner wall of the outer pipe of the U-shaped double-wall heat transfer pipe is provided with a groove, and the inner pipe and the outer pipe of the U-shaped double-wall heat transfer pipe are tightly attached.

Further, the inner pipe and the outer pipe of the U-shaped double-wall heat transfer pipe are made of the same metal material or different metal materials.

Further, when the direct current steam generator with the U-shaped double-wall heat transfer pipe is used in a lead bismuth stack system, the outer pipe of the U-shaped double-wall heat transfer pipe is made of a metal material resistant to lead bismuth corrosion, or a corrosion-resistant coating is sprayed and electroplated on the surface of the outer pipe of the U-shaped double-wall heat transfer pipe.

Further, the shape of the U-shaped double-wall heat transfer pipe direct current steam generator is fan-shaped, rectangular, circular and the like.

Furthermore, the diameter of the inner pipe of the U-shaped double-wall heat transfer pipe is 3-20mm, and the wall thickness is 0.5-5 mm; the diameter of the outer pipe of the U-shaped double-wall heat transfer pipe is 4-28mm, and the wall thickness is 0.5-5 mm.

Further, the tube side pressure of the U-shaped double-wall heat transfer tube direct-current steam generator is up to 35MPa at most, and the shell side pressure of the U-shaped double-wall heat transfer tube direct-current steam generator is up to 5MPa at most.

The invention has the beneficial technical effects that:

according to the direct current steam generator with the U-shaped double-wall heat transfer pipe, the structural unit of the U-shaped double-wall heat transfer pipe is adopted in the structural form of the traditional direct current steam generator with the U-shaped single-wall heat transfer pipe, so that the great damage and damage caused by corrosion and damage of the heat transfer pipe of the high-temperature liquid metal stack can be effectively solved, and the reliability and the safety of equipment are greatly improved. Whether the single-layer damage of the heat transfer pipe is monitored effectively by arranging the double pipe plates and the middle chamber.

The U-shaped double-wall heat transfer pipe direct-current steam generator adopts the U-shaped double-wall heat transfer pipe, double isolation of a pipe side medium and a shell side medium is realized, and the probability of contact of cold and hot media caused by leakage of the heat transfer pipe is reduced by half.

The U-shaped double-wall heat transfer pipe direct-current steam generator adopts the U-shaped double-wall heat transfer pipe, and medium on the pipe side of the U-shaped double-wall heat transfer pipe is positioned on the same side of the steam pipe plate, so that the direct-current steam generator is suitable for structural arrangement of a pool type reactor.

The U-shaped double-wall heat transfer pipe direct-current steam generator only fixes the pipe end of the U-shaped double-wall heat transfer pipe, and the other end of the U-shaped double-wall heat transfer pipe direct-current steam generator can freely expand, so that the U-shaped double-wall heat transfer pipe direct-current steam generator is suitable for the high-temperature characteristic of a liquid metal pile.

According to the direct-current steam generator with the U-shaped double-wall heat transfer pipe, the U-shaped double-wall heat transfer pipe adopts a gapless fit structure, so that the structural compactness is realized, and meanwhile, the heat transfer performance between the inner pipe wall and the outer pipe wall is greatly improved.

The direct current steam generator with the U-shaped double-wall heat transfer pipe has the advantages that the middle parts of the U-shaped double-wall heat transfer pipe are tightly attached, no obvious flow channel gap exists between the inner wall pipe and the outer wall pipe, even if the inner wall pipe is damaged and leaked, the leakage amount can be inhibited, and the direct current steam generator has sufficient reaction time and operation time.

According to the direct current steam generator with the U-shaped double-wall heat transfer pipe, the inner pipe wall and the outer pipe wall of the U-shaped double-wall heat transfer pipe are physically separated, and corrosion cracks of a single-layer pipe cannot extend to the other layer of pipe wall.

According to the direct-current steam generator with the U-shaped double-wall heat transfer pipe, the outer pipe of the U-shaped double-wall heat transfer pipe has a certain supporting effect on the inner pipe, and the wall thickness allowance of the inner pipe due to high-pressure medium of a pipe side can be reduced.

Drawings

FIG. 1 is a schematic structural view of a once-through steam generator with U-shaped double-wall heat transfer tubes according to example 1;

FIG. 2 is a schematic structural view of a once-through steam generator with U-shaped double-wall heat transfer tubes according to example 2;

FIG. 3 is a schematic structural view of a once-through steam generator with U-shaped double-wall heat transfer tubes according to example 3;

FIG. 4 is a front view of a liquid metal reactor vessel using a U-shaped double wall heat transfer tube once through steam generator of the present invention;

FIG. 5 is a top plan view of a liquid metal reactor vessel using the U-shaped double wall heat transfer tube once-through steam generator of example 1;

FIG. 6 is a schematic view of a one-piece aperture window construction;

FIG. 7 is a schematic view of a porous window structure of circular type;

FIG. 8 is a schematic view of a porous window of elliptical cylindrical shape;

FIG. 9 is a schematic view of a rectangular porous window structure;

FIG. 10 is a schematic view of a U-shaped double-walled heat transfer tube with the arced tube being a semi-circular tube;

FIG. 11 is a schematic view of a U-shaped double-walled heat transfer tube with a semicircular arc-shaped tube and a straight tube;

FIG. 12 is a schematic view of a U-shaped double wall heat transfer tube with the arced tube being a semi-elliptical tube;

FIG. 13 is a schematic view of a U-shaped double-walled heat transfer tube with a semi-elliptical arc tube and a straight tube;

FIG. 14 is a schematic view of a circumferential arrangement of U-shaped double wall heat transfer tubes;

FIG. 15 is a schematic view of a radial arrangement of U-shaped double-walled heat transfer tubes;

FIG. 16 is a schematic view of a U-shaped double-wall heat transfer pipe configuration according to example 1;

FIG. 17 is a schematic view of a U-shaped double-walled heat transfer tube configuration of examples 2 and 3;

FIG. 18 is a schematic outer view of a U-shaped double-wall heat transfer tube once-through steam generator according to example 1;

FIG. 19 is a schematic outer view of a U-shaped double-wall heat transfer tube once-through steam generator according to example 2;

FIG. 20 is a schematic outer view of a U-shaped double-wall heat transfer tube once-through steam generator according to example 3.

In the figure, 1, a cylinder; 2. a U-shaped double-wall heat transfer tube; 3. a shell side inlet window; 4. a tube bundle accommodating space 5, a tube plate; 6. an upper tube sheet; 7. a lower tube plate; 8. an inert gas containment chamber; 9. a steam inlet end enclosure; 10. a steam outlet end enclosure; 11. a steam inlet chamber; 12. a vapor outlet chamber; 13. a steam inlet connection pipe; 14. a steam outlet connection pipe; 15. a liquid metal reactor vessel; 16. a cold-hot tank partition plate; 17. a primary coolant; 18. the invention relates to a direct current steam generator with U-shaped double-wall heat transfer pipes; 19. a core; 20. an inner tube of the U-shaped double-wall heat transfer tube; 21. an outer tube of the U-shaped double-wall heat transfer tube; 22. and (4) a groove.

Detailed Description

In the description of the present invention, it is to be understood that the terms "left end", "right end", "above", "below", "outside", "inside", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, are not to be construed as limiting the present invention.

Referring to fig. 1-3, the present invention provides a U-shaped double-wall heat transfer tube direct current steam generator, which comprises a steam seal head, a steam tube plate, a steam connection tube, a tube bundle support member and a cylinder 1; the steam seal head lower extreme is connected with steam tube sheet upper end, connect the steam takeover on the steam seal head, steam tube sheet lower extreme is connected with barrel 1 and forms tube bank accommodation space 4, set up the tube bank in the tube bank accommodation space 4, the tube bank is formed by 2 dishes of a plurality of U-shaped double-walled heat-transfer pipes, support by tube bank supporting component between the U-shaped double-walled heat-transfer pipe 2, the pipe end and the steam tube sheet of tube bank are connected, barrel 1 is equipped with shell side import window 3.

The U-shaped double-wall heat transfer pipe direct-flow steam generator is similar to the traditional U-shaped single-wall heat transfer pipe direct-flow steam generator in structure, and the flow channels of media on two sides of the steam generator are constructed by a cylinder, an end socket, a pipe bundle, a pipe plate, a connecting pipe, a pipe bundle supporting structure and the like. The U-shaped double-wall heat transfer pipe once-through steam generator of the invention is mainly different from the traditional U-shaped single-wall heat transfer pipe once-through steam generator in that: firstly, the U-shaped double-wall heat transfer pipe direct-current steam generator adopts the U-shaped double-wall heat transfer pipe 2 as a main heat transfer unit, so that the reliability of the steam generator is improved; secondly, the U-shaped double-wall heat transfer pipe direct current steam generator is arranged in the liquid metal reactor vessel 15, the shell pass of the cylinder 1 of the steam generator has no inlet and outlet connecting pipe, and an inlet and outlet window is arranged at the corresponding position of the shell pass of the cylinder 1 according to the requirement. Referring to fig. 1, in one embodiment, the steam tube sheet is a single tube sheet, the steam tube sheet includes a tube sheet 5, and the inner tubes 20 of the U-shaped double-walled heat transfer tubes and the outer tubes 21 of the U-shaped double-walled heat transfer tubes are each welded to the tube sheet 5.

Referring to fig. 2, in one embodiment, the steam tube plate is a double tube plate, the steam tube plate comprises an upper tube plate 6 and a lower tube plate 7, the inner tubes 20 of the U-shaped double-wall heat transfer tubes are welded with the upper tube plate 6, and the outer tubes 21 of the U-shaped double-wall heat transfer tubes are welded with the lower tube plate 7; an inert gas containing chamber 8 is formed between the upper tube plate 6 and the lower tube plate 7, and inert gas is filled in the inert gas containing chamber 8; the filling pressure is lower than the medium pressure of an inner pipe 20 of the U-shaped double-wall heat transfer pipe and higher than the medium pressure of an outer pipe 21 of the U-shaped double-wall heat transfer pipe; the breakage and leakage of the inner pipe 20 of the U-shaped double-wall heat transfer pipe and the outer pipe 21 of the U-shaped double-wall heat transfer pipe can be found in time by monitoring the pressure of the inert gas containing chamber 8, and if the pressure of the inert gas containing chamber 8 is reduced, the outer pipe 21 of the U-shaped double-wall heat transfer pipe leaks; if the inert gas containing chamber 8 is pressurized, the inner tube 20, which is a U-shaped double-walled heat transfer tube, leaks.

Further, the steam connection pipe includes a steam inlet connection pipe 13 and a steam outlet connection pipe 14.

Referring to fig. 1-2, in one embodiment, the steam seal head is a split type, and includes a steam inlet seal head 9 and a steam outlet seal head 10, a steam inlet connecting pipe 13 is connected to the steam inlet seal head 9, and a steam outlet connecting pipe 14 is connected to the steam outlet seal head 10.

Referring to fig. 3, in one embodiment, the steam head is an integral type, a partition plate is arranged in the middle of the steam head to form a steam inlet chamber 11 and a steam outlet chamber 12, a steam inlet connecting pipe 13 is connected to the steam inlet chamber 11, and a steam outlet connecting pipe 14 is connected to the steam outlet chamber 12.

The steam seal head of the U-shaped double-wall heat transfer pipe direct-current steam generator is not limited to the schematic type in the figures 1-3, other structural forms can be adopted, and the orientation of the steam connecting pipe on the steam seal head can be adjusted.

Further, referring to fig. 4-5, the U-shaped double-walled heat transfer tube once-through steam generator is located in the liquid metal reactor vessel 15, and the steam tube plate of the U-shaped double-walled heat transfer tube 2 once-through steam generator is hermetically connected with the top cover of the liquid metal reactor vessel 15 to form a shell side closed space. The liquid metal reactor refers to a reactor using liquid metal as a coolant, and mainly comprises a sodium-cooled fast reactor, a lead-bismuth fast reactor, a lead-cooled fast reactor, a sodium-potassium reactor, a lithium-potassium reactor, a lead-lithium reactor, a liquid-mercury reactor and the like, and other metal reactors which are not listed in detail.

Further, the steam tube plate of the U-shaped double-walled heat transfer tube once-through steam generator is flange-sealed or welded-sealed to the head of the liquid metal reactor vessel 15.

The barrel 1 of the U-shaped double-wall heat transfer pipe once-through steam generator can be adjusted according to requirements.

Further, the shell side inlet window 3 is arranged on the side or below the cylinder body 1.

Referring to fig. 6, in one embodiment, the shell-side inlet window 3 is a sheet of hole window.

Referring to fig. 7-9, in one embodiment, the shell-side inlet window 3 is a porous window with holes in the shape of a circle, an elliptic cylinder, or a rectangle. The pattern of the holes of the porous window is not limited to that shown in fig. 7 to 9, but may be kidney-shaped, diamond-shaped, regular hexagon, etc.

The U-shaped double-wall heat transfer pipe 2 comprises a straight pipe and an arc pipe, two ends of the arc pipe are respectively connected with a straight pipe, and the straight pipe and the arc pipe are integrally formed; referring to fig. 10-13, the arced tube may be a semi-circular tube, a semi-circular straight tube, a semi-elliptical tube, or a semi-elliptical straight tube; the turning arc of the semi-elliptic pipe with the straight section can be an arc, an elliptic arc and other nonstandard lofting smooth curves.

Referring to fig. 14-15, the U-shaped double-walled heat transfer tube 2 may be arranged circumferentially or radially.

Referring to fig. 16, in one embodiment, the inner tube 20 of the U-shaped double wall heat transfer tube and the outer tube 21 of the U-shaped double wall heat transfer tube are in close proximity.

Referring to fig. 17, in one embodiment, the inner wall of the outer tube 21 of the U-shaped double-walled heat transfer tube is provided with grooves 22, and the inner tube 20 of the U-shaped double-walled heat transfer tube and the outer tube 21 of the U-shaped double-walled heat transfer tube are closely attached.

The U-shaped double-wall heat transfer pipe direct-current steam generator has the advantages that the middle of the U-shaped double-wall heat transfer pipe 2 is tightly attached, no obvious flow channel gap exists between the inner wall pipe and the outer wall pipe, even if the inner wall pipe is damaged and leaked, the leakage amount can be inhibited, and the sufficient reaction time and operation time are realized.

The inner tube 20 of the U-shaped double-wall heat transfer tube and the outer tube 21 of the U-shaped double-wall heat transfer tube can be made of the same metal material or different metal materials, are selected according to the operation parameters, corrosion characteristics and other conditions of a tube side medium and a shell side medium of the steam generator, and cannot be influenced by structural differences. When the tube is used in a lead-bismuth stack system, the outer tube 21 of the U-shaped double-wall heat transfer tube can be made of a metal material resistant to lead-bismuth corrosion according to the requirement, or the surface of the outer tube 21 of the U-shaped double-wall heat transfer tube is coated and electroplated with a corrosion-resistant coating.

Referring to fig. 18-20, the profile of the U-shaped double-walled heat transfer tube once-through steam generator can be adjusted according to the system layout, and can be fan-shaped, rectangular, circular, etc.

The structural size of the U-shaped double-wall heat transfer pipe once-through steam generator is not limited, including the diameter, the wall thickness, the height and the like, and can be enlarged and reduced according to the scale of a reactor. The U-shaped double-wall heat transfer pipe 2 can be designed into different specifications according to requirements, and the specification of the U-shaped double-wall heat transfer pipe 2 is selected according to the operation flow parameters of equipment and the size limit of the equipment; the wall thickness of the U-shaped double-wall heat transfer pipe 2 is determined by comprehensive calculation according to the factors such as the operating temperature, the pressure, the medium corrosion condition and the like. Preferably, the inner pipe 20 of the U-shaped double-wall heat transfer pipe has the diameter of 3-20mm and the wall thickness of 0.5-5 mm; the diameter of the outer pipe 21 of the U-shaped double-wall heat transfer pipe is 4-28mm, and the wall thickness is 0.5-5 mm.

The running temperature, pressure and the like of the U-shaped double-wall heat transfer pipe direct-current steam generator are also quite wide, the pipe side pressure can reach 25MPa or more and the shell side pressure can reach 2MPa or more according to the selected materials and specification.

The present invention will be described in further detail with reference to the accompanying drawings and examples.

Example 1

Referring to fig. 1, the present invention provides a U-shaped double-wall heat transfer tube direct current steam generator, which comprises a steam seal head, a steam tube plate, a steam connection tube, a tube bundle support component and a cylinder 1; the steam seal head lower extreme is connected with steam tube sheet upper end, connect the steam takeover on the steam seal head, steam tube sheet lower extreme is connected with barrel 1 and forms tube bank accommodation space 4, set up the tube bank in the tube bank accommodation space 4, the tube bank is formed by 2 dishes of a plurality of U-shaped double-walled heat-transfer pipes, support by tube bank supporting component between the U-shaped double-walled heat-transfer pipe 2, the pipe end and the steam tube sheet of tube bank are connected, barrel 1 is equipped with shell side import window 3.

Referring to fig. 1, the steam tube plate is a single tube plate, the steam tube plate includes a tube plate 5, and the inner tube 20 of the U-shaped double-wall heat transfer tube and the outer tube 21 of the U-shaped double-wall heat transfer tube are both welded to the tube plate 5.

Referring to fig. 1, the steam nipple includes a steam inlet nipple 13 and a steam outlet nipple 14.

Referring to fig. 1, the steam seal head is split and comprises a steam inlet seal head 9 and a steam outlet seal head 10, the steam inlet seal head 9 is connected with a steam inlet connecting pipe 13, and the steam outlet seal head 10 is connected with a steam outlet connecting pipe 14.

Referring to fig. 4-5, the U-shaped double-walled heat transfer tube once-through steam generator is located in the liquid metal reactor vessel 15, and a steam tube plate of the U-shaped double-walled heat transfer tube once-through steam generator is hermetically connected with a head cover of the liquid metal reactor vessel 15 to form a shell side enclosed space. The steam tube plate of the U-shaped double-wall heat transfer tube direct-current steam generator is connected with the top cover of the liquid metal reactor vessel 15 in a flange sealing mode or in a welding sealing mode.

Referring to fig. 1, the shell side inlet window 3 is arranged on the upper side of the cylinder 1. The barrel 1 of the U-shaped double-wall heat transfer pipe once-through steam generator can be adjusted according to requirements.

Referring to fig. 6, the shell-side inlet window 3 is a one-piece hole window.

Referring to fig. 16, the inner tube 20 of the U-shaped double-walled heat transfer tube and the outer tube 21 of the U-shaped double-walled heat transfer tube are closely fitted.

According to the direct current steam generator with the U-shaped double-wall heat transfer pipe, the middle of the U-shaped double-wall heat transfer pipe 2 is tightly attached, no obvious flow channel gap exists between the inner wall pipe and the outer wall pipe, even if the inner wall pipe is damaged and leaked, the leakage amount can be inhibited, and sufficient reaction time and operation time are provided.

Referring to fig. 18, the U-shaped double-walled heat transfer tube once-through steam generator has a fan shape.

The structural size of the U-shaped double-wall heat transfer pipe once-through steam generator is not limited, including the diameter, the wall thickness, the height and the like, and can be enlarged and reduced according to the scale of a reactor. The U-shaped double-wall heat transfer pipe 2 can be designed into different specifications according to requirements, and the specification of the U-shaped double-wall heat transfer pipe 2 is selected according to the operation flow parameters of equipment and the size limit of the equipment; the wall thickness of the U-shaped double-wall heat transfer pipe 2 is determined by comprehensive calculation according to the factors such as the operating temperature, the pressure, the medium corrosion condition and the like. Preferably, the inner tube 20 of the U-shaped double-wall heat transfer tube has a diameter of 3-20mm and a wall thickness of 0.5-5 mm; the diameter of an outer pipe 21 of the U-shaped double-wall heat transfer pipe is 4-28mm, and the wall thickness is 0.5-5 mm.

Example 2

Referring to fig. 2, the present invention provides a U-shaped double-wall heat transfer tube dc steam generator, which comprises a steam seal head, a steam tube plate, a steam connection tube, a tube bundle support member and a cylinder 1; the steam seal head lower extreme is connected with steam tube sheet upper end, connect the steam takeover on the steam seal head, steam tube sheet lower extreme is connected with barrel 1 and forms tube bank accommodation space 4, set up the tube bank in the tube bank accommodation space 4, the tube bank is formed by 2 dishes of a plurality of U-shaped double-walled heat-transfer pipes, support by tube bank supporting component between the U-shaped double-walled heat-transfer pipe 2, the pipe end and the steam tube sheet of tube bank are connected, barrel 1 is equipped with shell side import window 3.

Referring to fig. 2, the steam tube plate is a double-tube plate, the steam tube plate comprises an upper tube plate 6, a tube plate 5 and a lower tube plate 7, an inner tube 20 of the U-shaped double-wall heat transfer tube is welded with the upper tube plate 6, and an outer tube 21 of the U-shaped double-wall heat transfer tube is welded with the lower tube plate 7; an inert gas containing chamber 8 is formed between the upper tube plate 6 and the lower tube plate 7, and inert gas is filled in the inert gas containing chamber 8; the filling pressure is lower than the medium pressure of an inner pipe 20 of the U-shaped double-wall heat transfer pipe and higher than the medium pressure of an outer pipe 21 of the U-shaped double-wall heat transfer pipe; the breakage and leakage of the inner pipe 20 of the U-shaped double-wall heat transfer pipe and the outer pipe 21 of the U-shaped double-wall heat transfer pipe can be found in time by monitoring the pressure of the inert gas containing chamber 8, and if the pressure of the inert gas containing chamber 8 is reduced, the outer pipe 21 of the U-shaped double-wall heat transfer pipe leaks; if the inert gas containing chamber 8 is pressurized, the inner tube 20, which is a U-shaped double-walled heat transfer tube, leaks.

The steam connection comprises a steam inlet connection 13 and a steam outlet connection 14.

Referring to fig. 2, the steam seal head is split and comprises a steam inlet seal head 9 and a steam outlet seal head 10, the steam inlet seal head 9 is connected with a steam inlet connecting pipe 13, and the steam outlet seal head 10 is connected with a steam outlet connecting pipe 14.

Referring to fig. 4, the U-shaped double-walled heat transfer tube once-through steam generator is located in the liquid metal reactor vessel 15, and a steam tube plate of the U-shaped double-walled heat transfer tube once-through steam generator is hermetically connected with a head cover of the liquid metal reactor vessel 15 to form a shell-side enclosed space. And the steam tube plate of the U-shaped tube steam generator is in flange sealing connection or welding sealing connection with the top cover of the liquid metal reactor vessel 15.

Referring to fig. 2, the shell side inlet window 3 is arranged on the upper side of the cylinder 1. The barrel 1 of the U-shaped double-wall heat transfer pipe once-through steam generator can be adjusted according to requirements.

Referring to fig. 7-9, the shell-side inlet window 3 is a porous window with holes in the shape of a circle, an elliptic cylinder, or a rectangle. The pattern of the holes of the porous window is not limited to that shown in fig. 7 to 9, but may be kidney-shaped, diamond-shaped, regular hexagon, etc.

Referring to fig. 17, grooves 22 are formed on the inner wall of the outer tube 21 of the U-shaped double-walled heat transfer tube, and the inner tube 20 of the U-shaped double-walled heat transfer tube and the outer tube 21 of the U-shaped double-walled heat transfer tube are closely attached.

Referring to fig. 19, the U-shaped double-walled heat transfer tube once-through steam generator has a rectangular outer shape.

The structural size of the U-shaped double-wall heat transfer pipe once-through steam generator is not limited, including the diameter, the wall thickness, the height and the like, and can be enlarged and reduced according to the scale of a reactor. The U-shaped double-wall heat transfer pipe 2 can be designed into different specifications according to requirements, and the specification of the U-shaped double-wall heat transfer pipe 2 is selected according to the operation flow parameters of equipment and the size limit of the equipment; the wall thickness of the U-shaped double-wall heat transfer pipe 2 is determined by comprehensive calculation according to the factors such as the operating temperature, the pressure, the medium corrosion condition and the like. Preferably, the inner pipe 20 of the U-shaped double-wall heat transfer pipe has the diameter of 3-20mm and the wall thickness of 0.5-5 mm; the diameter of an outer pipe 21 of the U-shaped double-wall heat transfer pipe is 4-28mm, and the wall thickness is 0.5-5 mm.

Example 3

Referring to fig. 3, the present invention provides a U-shaped double-wall heat transfer tube dc steam generator, which includes a steam seal head, a steam tube plate, a steam connection tube, a tube bundle support member and a cylinder 1; the steam seal head lower extreme is connected with steam tube sheet upper end, connect the steam takeover on the steam seal head, steam tube sheet lower extreme is connected with barrel 1 and forms tube bank accommodation space 4, set up the tube bank in the tube bank accommodation space 4, the tube bank is formed by 2 dishes of a plurality of U-shaped double-walled heat-transfer pipes, support by tube bank supporting component between the U-shaped double-walled heat-transfer pipe 2, the pipe end and the steam tube sheet of tube bank are connected, barrel 1 is equipped with shell side import window 3.

Referring to fig. 3, the steam tube plate is a double tube plate, the steam tube plate comprises an upper tube plate 6 and a lower tube plate 7, an inner tube 20 of the U-shaped double-wall heat transfer tube is welded with the upper tube plate 6, and an outer tube 21 of the U-shaped double-wall heat transfer tube is welded with the lower tube plate 7; an inert gas containing chamber 8 is formed between the upper tube plate 6 and the lower tube plate 7, and inert gas is filled in the inert gas containing chamber 8; the filling pressure is less than the medium pressure of the inner pipe 20 of the U-shaped double-wall heat transfer pipe and greater than the medium pressure of the outer pipe of the U-shaped double-wall heat transfer pipe; the breakage and leakage of the inner pipe 20 of the U-shaped double-wall heat transfer pipe and the outer pipe 21 of the U-shaped double-wall heat transfer pipe can be found in time by monitoring the pressure of the inert gas containing chamber 8, and if the pressure of the inert gas containing chamber 8 is reduced, the outer pipe 21 of the U-shaped double-wall heat transfer pipe leaks; if the inert gas containing chamber 8 is pressurized, the inner tube 20, which is a U-shaped double-walled heat transfer tube, leaks.

Referring to fig. 3, the steam seal head is integrated, a partition plate is arranged in the middle of the steam seal head to form a steam inlet chamber 11 and a steam outlet chamber 12, the steam inlet chamber 11 is connected with a steam inlet connecting pipe 13, and the steam outlet chamber 12 is connected with a steam outlet connecting pipe 14.

Referring to fig. 17, the inner wall of the outer tube 21 of the U-shaped double-walled heat transfer tube is provided with grooves 22, and the inner tube 20 of the U-shaped double-walled heat transfer tube and the outer tube 21 of the U-shaped double-walled heat transfer tube are closely attached.

Referring to fig. 20, the U-shaped double-walled heat transfer tube once-through steam generator has a circular outer shape.

The structural size of the straight-flow steam generator with the U-shaped double-wall heat transfer pipe is not limited to any diameter, wall thickness, height and the like, and can be enlarged or reduced according to the scale of a reactor. The U-shaped double-wall heat transfer pipe 2 can be designed into different specifications according to requirements, and the specification of the U-shaped double-wall heat transfer pipe 2 is selected according to the operation flow parameters of equipment and the size limit of the equipment; the wall thickness of the U-shaped double-wall heat transfer pipe 2 is determined by comprehensive calculation according to the factors such as the operating temperature, the pressure, the medium corrosion condition and the like. Preferably, the inner tube 20 of the U-shaped double-wall heat transfer tube has a diameter of 3-20mm and a wall thickness of 0.5-5 mm; the diameter of the outer pipe 21 of the U-shaped double-wall heat transfer pipe is 4-28mm, and the wall thickness is 0.5-5 mm.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The utility model provides a U-shaped double-walled heat-transfer pipe direct current steam generator, its characterized in that includes steam head, steam tube sheet, steam takeover, tube bank supporting component and barrel (1), the steam head lower extreme is connected with steam tube sheet upper end, connect steam takeover on the steam head, steam tube sheet lower extreme is connected with barrel (1) and is formed tube bank accommodation space (4), set up the tube bank in tube bank accommodation space (4), the tube bank is coiled by a plurality of U-shaped double-walled heat-transfer pipes (2) and is formed, support by tube bank supporting component between U-shaped double-walled (2), the pipe end and the steam tube sheet of tube bank are connected, barrel (1) is equipped with shell side import window (3).

2. The U-shaped double wall heat transfer tube once-through steam generator of claim 1, characterized in that said steam tube sheet is a single tube sheet, said steam tube sheet comprising a tube sheet (5), and said inner tubes (20) of the U-shaped double wall heat transfer tubes and said outer tubes (21) of the U-shaped double wall heat transfer tubes are both welded to the tube sheet (5).

3. The U-shaped double wall heat transfer tube once-through steam generator of claim 1, characterized in that the steam tube sheet is a double tube sheet, the steam tube sheet comprising an upper tube sheet (6) and a lower tube sheet (7), the inner tubes (20) of the U-shaped double wall heat transfer tubes being welded to the upper tube sheet (6), the outer tubes (21) of the U-shaped double wall heat transfer tubes being welded to the lower tube sheet (7); an inert gas containing chamber (8) is formed between the upper tube plate (6) and the lower tube plate (7), and inert gas is filled in the inert gas containing chamber (8); the filling pressure is lower than the medium pressure of an inner pipe (20) of the U-shaped double-wall heat transfer pipe, and the filling pressure is higher than the medium pressure of an outer pipe (21) of the U-shaped double-wall heat transfer pipe.

4. The U-shaped double wall heat transfer tube once-through steam generator of claim 1, characterized in that the steam connection comprises a steam inlet connection (13) and a steam outlet connection (14).

5. The U-shaped double-wall heat transfer pipe direct current steam generator of claim 4, characterized in that the steam end socket is a split type and comprises a steam inlet end socket (9) and a steam outlet end socket (10), wherein the steam inlet end socket (9) is connected with a steam inlet connecting pipe (13), and the steam outlet end socket (10) is connected with a steam outlet connecting pipe (14).

6. The U-shaped double-wall heat transfer pipe direct current steam generator of claim 4, characterized in that the steam head is an integral body, a partition plate is arranged in the middle of the steam head to form a steam inlet chamber (11) and a steam outlet chamber (12), the steam inlet chamber (11) is connected with a steam inlet connecting pipe (13), and the steam outlet chamber (12) is connected with a steam outlet connecting pipe (14).

7. The U-shaped double wall heat transfer tube once-through steam generator of claim 1, wherein the shell side inlet window (3) is provided at the side or below the cylinder (1).

8. The U-shaped double wall heat transfer tube once-through steam generator of claim 7, characterized in that the shell side inlet window (3) is a one-piece or multi-hole window.

9. A U-shaped double wall heat transfer tube once through steam generator as set forth in claim 8 wherein the pattern of holes of the porous window is circular, elliptical cylindrical, rectangular, kidney-shaped, diamond-shaped, or regular hexagonal.

10. The U-shaped double-wall heat transfer pipe direct current steam generator according to claim 1, wherein the U-shaped double-wall heat transfer pipe (2) comprises a straight pipe and an arc pipe, wherein the two ends of the arc pipe are respectively connected with a straight pipe, and the straight pipe and the arc pipe are integrally formed; the arc-shaped pipe is a semicircular pipe, a semicircular straight section pipe, a semi-elliptical pipe or a semi-elliptical straight section pipe; the turning arc of the semi-elliptic pipe with the straight section is an arc, an elliptic arc or a nonstandard lofting smooth curve.

11. A U-shaped double wall heat transfer tube once-through steam generator according to claim 1, characterized in that the U-shaped double wall heat transfer tubes (2) are arranged circumferentially or radially.

12. The U-shaped double wall heat transfer tube once-through steam generator of claim 1, wherein the inner tube (20) of the U-shaped double wall heat transfer tube and the outer tube (21) of the U-shaped double wall heat transfer tube are closely fitted.

13. The straight-flow steam generator with U-shaped double-wall heat transfer tubes according to claim 1, characterized in that the inner wall of the outer tube (21) of the U-shaped double-wall heat transfer tubes is provided with grooves (22), and the inner tube (20) of the U-shaped double-wall heat transfer tubes and the outer tube (21) of the U-shaped double-wall heat transfer tubes are in close fit.

14. The U-shaped double wall heat transfer tube once-through steam generator of claim 1, characterized in that the inner tube (20) of the U-shaped double wall heat transfer tube has a diameter of 3-20mm and a wall thickness of 0.5-5 mm; the diameter of an outer pipe (21) of the U-shaped double-wall heat transfer pipe is 4-28mm, and the wall thickness is 0.5-5 mm.

15. The U-shaped double wall heat transfer tube once-through steam generator of claim 1, wherein the U-shaped double wall heat transfer tube once-through steam generator is fan-shaped, rectangular or circular in shape.

16. The U-shaped double wall heat transfer tube once-through steam generator of claim 1, wherein the U-shaped double wall heat transfer tube once-through steam generator has a tube side pressure of up to 25MPa and a shell side pressure of up to 5 MPa.

17. The U-shaped double wall heat transfer tube once-through steam generator according to any one of claims 1 to 16, characterized in that the U-shaped double wall heat transfer tube once-through steam generator is used in a liquid metal reactor vessel (15), and a steam tube plate of the U-shaped double wall heat transfer tube (2) once-through steam generator is in sealed connection with a head cover of the liquid metal reactor vessel (15) to form a shell side enclosed space.

18. A U-shaped double wall heat transfer tube once-through steam generator according to claim 17, characterized in that the steam tube sheet of the U-shaped double wall heat transfer tube once-through steam generator is flange-sealed or weld-sealed to the liquid metal reactor vessel (15) top cover.