Steam generator for lead-bismuth fast reactor and reactor applicable to steam generator

Abstract

The embodiment of the invention relates to the technical field of steam generation methods, in particular to a steam generator for a lead-bismuth fast reactor and a reactor applicable to the steam generator. In a first aspect, the steam generator for the lead-bismuth fast reactor comprises a body and a heat exchange tube, the body is arranged to form a first cavity and a second cavity in the body, the heat exchange tube is in fluid communication with the first cavity, a part of the heat exchange tube is arranged in the second cavity, and the first cavity is communicated with the second cavity. And the other part of the lead-bismuth liquid passes through the second cavity and enters a loop lead-bismuth liquid. On the second aspect, the embodiment of the invention further provides a reactor, and the reactor comprises the steam generator in the first aspect of the application. According to the steam generator and the reactor comprising the steam generator, most of the structure of the steam generator can be arranged in the reactor container, and compared with a traditional steam generator, the steam generator is more compact in size and can be integrated with the reactor container, so that the size of the whole reactor is reduced.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of steam generation methods, and specifically to a steam generator for a lead-bismuth fast reactor and a reactor suitable for the steam generator. Background Art

[0002] The statements herein merely provide background information related to the present application and do not necessarily constitute prior art.

[0003] The steam generator is a key device in the reactor used to generate steam required for nuclear power plants. It is the hub for heat transfer between the primary and secondary circuit media. Its main function is to realize heat exchange between the lead and bismuth in the primary circuit and the water in the secondary circuit, so that the water can be heated by lead and bismuth to generate the steam required for the secondary circuit.

[0004] The steam generator widely used at present is the shell and tube steam generator, which is mainly used in sodium-cooled fast reactors and is difficult to be applied to modular lead-bismuth fast reactors. Summary of the invention

[0005] A brief overview of the present application is provided below in order to provide a basic understanding of certain aspects of the present application. It should be understood that this overview is not an exhaustive overview of the present application. It is not intended to identify the key or important parts of the present application, nor is it intended to limit the scope of the present application. Its purpose is merely to present certain concepts in a simplified form as a prelude to a more detailed description discussed later.

[0006] In the first aspect, an embodiment of the present application provides a steam generator for a lead-bismuth fast reactor, which includes: a body, a heat exchange tube, the body is arranged to form a first chamber and a second chamber therein, a cold water inlet is formed at the position of the first chamber of the body, a steam outlet is formed at the position of the second chamber of the body, the heat exchange tube is in fluid communication with the first chamber, and a portion of the heat exchange tube is arranged in the second chamber, and extends so that another portion passes through the second chamber and enters the primary lead-bismuth liquid. Among them, cold water enters the first chamber from the cold water inlet and flows into a plurality of heat exchange tubes, and the steam generated after heat exchange through the plurality of heat exchange tubes flows out from the steam outlet.

[0007] In a second aspect, an embodiment of the present application further provides a reactor, comprising a steam generator according to any embodiment of the first aspect of the present application.

[0008] The steam generator and reactor for the lead-bismuth fast reactor in the embodiments of the present application are more compact than traditional steam generators because most of the structure of the steam generator can be arranged inside the reactor vessel, so they can be integrated with the reactor vessel, thereby reducing the volume of the entire reactor system. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Other objects and advantages of the present application will become apparent from the following description of the embodiments of the present application with reference to the accompanying drawings, and will help to provide a comprehensive understanding of the present application.

[0010] Figure 1 It is a schematic structural diagram of a steam generator for a lead-bismuth fast reactor according to an embodiment of the present application.

[0011] Figure 2 It is a schematic diagram of the connection structure between the heat exchange tube and the first plate body and the second plate body according to an embodiment of the present application.

[0012] Description of reference numerals:

[0013] 10. Main body; 11. First chamber; 111. Cold water inlet; 12. Second chamber; 121. Steam outlet; 20. Heat exchange tube; 21. First heat exchange tube body; 22. Second heat exchange tube body; 221. Insulation layer; 30. First plate body; 31. First through hole; 40. Second plate body; 41. Second through hole.

[0014] It should be noted that the drawings are not necessarily drawn to scale, but are merely shown in a schematic manner that does not affect the reader's understanding. DETAILED DESCRIPTION

[0015] Exemplary embodiments of the present application will be described below in conjunction with the accompanying drawings. For the sake of clarity and conciseness, not all features of the actual implementation are described in the specification. However, it should be understood that many implementation-specific decisions must be made in the process of developing any such actual implementation in order to achieve the developer's specific goals, such as meeting those constraints related to the system and business, and these constraints may vary from implementation to implementation. In addition, it should be understood that although the development work may be very complex and time-consuming, it is only a routine task for those skilled in the art who benefit from the content of this application.

[0016] It is also necessary to explain here that, in order to avoid obscuring the present application due to unnecessary details, only the device structure and / or processing steps closely related to the scheme according to the present application are shown in the accompanying drawings, while other details that are not very relevant to the present application are omitted.

[0017] The inventors of the present application discovered that since the shell and tube steam generator consists of two parts, an evaporator and a superheater, when it is used in a sodium-cooled fast reactor, the high-temperature liquid sodium in the first circuit first flows through the shell side of the evaporator to exchange heat with the second circuit cold water flowing through the tube side, so that the second circuit cold water is vaporized to generate steam, and then flows through the shell side of the superheater to heat the steam flowing through the tube side into superheated steam. Such structural requirements result in a larger volume of the shell and tube steam generator and a larger space requirement inside the reactor. Therefore, it is not suitable for a modular lead-bismuth fast reactor with a more compact structure and smaller volume.

[0018] Based on this, an embodiment of the present application provides a steam generator for a lead-bismuth fast reactor, such as Figure 1 As shown, Figure 1 The structural schematic diagram of a steam generator for a lead-bismuth fast reactor according to an embodiment of the present application is shown, and the steam generator includes: a body 10 and a heat exchange tube 20. The body 10 is configured to form a first chamber 11 and a second chamber 12 therein, a cold water inlet 111 is formed at the position of the first chamber 11 of the body 10, and a steam outlet 121 is formed at the position of the second chamber 12 of the body 10. The heat exchange tube 20 is in fluid communication with the first chamber 11, and a portion of it is arranged in the second chamber 12, and extends so that another portion passes through the second chamber 12 and enters the primary circuit lead-bismuth liquid. Among them, cold water enters the first chamber 11 from the cold water inlet 111 and flows into a plurality of heat exchange tubes 20, and the steam generated after heat exchange through the plurality of heat exchange tubes 20 flows out from the steam outlet 121.

[0019] The steam generator provided in the embodiment of the present application provides temporary storage space for cold water and steam generated after heat exchange by configuring the main body 10 to form a first chamber 11 and a second chamber 12 therein, respectively, and configuring the heat exchange tube 20 to be fluidically connected to the first chamber 11, with a portion of the heat exchange tube 20 being configured in the second chamber 12 and extending so that another portion passes through the second chamber 12 and enters the primary lead-bismuth liquid, so that a portion of the heat exchange tube 20 serving as the heat exchange main body directly contacts the primary lead-bismuth liquid and exchanges heat to generate steam, thereby enabling most of the structure of the steam generator to be configured in the reactor vessel, saving the space occupied by the steam generator inside the reactor and facilitating its use in a modular lead-bismuth fast reactor.

[0020] like Figure 1 As shown, in some embodiments, the steam generator may further include: a first plate body 30 and a second plate body 40, wherein the first plate body 30 and the second plate body 40 are arranged to be fixedly connected to the body 10, and are arranged such that the body 10 and the first plate body 30 form a first chamber 11, and the first plate body 30, the body 10 and the second plate body 40 form a second chamber 12. In this embodiment, the body 10 is divided into two mutually unconnected first chambers 11 and second chambers 12 by the first plate body 30 and the second plate body 40.

[0021] like Figure 1 As shown, in some embodiments, the heat exchange tube 20 may include a first heat exchange tube body 21 and a second heat exchange tube body 22, a portion of the second heat exchange tube body 22 is arranged inside the first heat exchange tube body 21, the lower end of the first heat exchange tube body 21 is closed, and the lower end of the second heat exchange tube body 22 is open; the upper end of the first heat exchange tube body 21 is in fluid communication with the second chamber 12, and the portion of the second heat exchange tube body 22 extending in the second chamber 12 is arranged outside the first heat exchange tube body 21. In this embodiment, the first heat exchange tube body 21 is arranged to be closed at the lower end, and the second heat exchange tube body 22 is arranged to be open at the lower end, so that a predetermined distance is left between the first heat exchange tube body 21 and the second heat exchange tube body 22 in the axial direction, so as to provide a telescopic space for the thermal expansion of the tube body, and to avoid the large thermal stress generated inside the tube body due to the temperature difference of the fluid on both sides of the tube body, thereby causing damage to the tube body.

[0022] like Figure 1 and Figure 2 As shown, Figure 2 A schematic diagram of the connection structure of the heat exchange tube 20, the first plate body 30 and the second plate body 40 according to an embodiment of the present application is shown. In some embodiments, the first plate body 30 is formed with a first through hole 31, and the second plate body 40 is formed with a second through hole 41; the second heat exchange tube body 22 extends into the second chamber 12 through the second through hole 41 and is connected to the first through hole 31, so that the cold water in the first chamber 11 enters the second heat exchange tube body 22 through the first through hole 31; the first heat exchange tube body 21 is fixedly connected to the second through hole 41, so that the steam in the first heat exchange tube body 21 enters the second chamber 12 through the second through hole 41.

[0023] In some embodiments, the second heat exchange tube body 22 can be insulated to reduce the heat exchange between the fluid inside the second heat exchange tube body 22 and the fluid in the first heat exchange tube body 21, that is, to reduce the possibility that the steam in the first heat exchange tube body 21 is cooled into water by the cold water in the second heat exchange tube body 22, thereby improving the heat exchange efficiency of the steam generator and ensuring that the amount of steam generated by the heat exchange and the steam temperature meet the predetermined requirements.

[0024] like Figure 2 As shown, in some embodiments, a heat insulation layer 221 may be formed inside the second heat exchange tube body 22 to achieve heat insulation treatment of the second heat exchange tube body 22. For example, the heat insulation layer 221 may be filled with a heat insulating material.

[0025] In some embodiments, the first heat exchange tube body 21 and the second heat exchange tube body 22 can be arranged to be radially concentric to form a flow channel of uniform size between the first heat exchange tube body 21 and the second heat exchange tube body 22, thereby avoiding flow velocity differences caused by inconsistent flow channel sizes, ensuring that the fluid flows evenly in the flow channel, making the heat exchange between the fluids more sufficient and efficient, and thereby improving the heat exchange efficiency of the steam generator.

[0026] In some embodiments, a sharp corner is formed at the lower end of the second heat exchange tube body 22 .

[0027] An embodiment of the present application also provides a reactor, which includes a steam generator according to any embodiment of the first aspect of the present application.

[0028] In the reactor provided in the embodiments of the present application, since most of the structure of the steam generator of the first aspect of the present application can be arranged in the reactor vessel, it is more compact than the traditional steam generator and can be integrated with the reactor vessel, thereby reducing the volume of the entire reactor system.

[0029] In some embodiments, the reactor also includes a stack container and a stack cover. The stack cover is arranged on the stack container. A channel is arranged in the stack cover. The steam generator is arranged in the channel so that most of the structure of the steam generator can be arranged in the stack container, thereby reducing the space occupied by the steam generator in the reactor.

[0030] In some embodiments, the reactor also includes a secondary cooling system, the first chamber 11 is fluidically connected to the secondary cooling system, and cold water from the secondary cooling system flows into the first chamber 11 from the cold water inlet 111 of the first chamber 11, so as to flow from the first chamber 11 into the heat exchange tube 20 to exchange heat with the lead-bismuth liquid.

[0031] The cold water inlet 111 of the first chamber 11 can be arranged at the top of the body 10 to facilitate connection with the secondary cooling system of the reactor, thereby facilitating the arrangement of the steam generator in the channel of the upper cover of the reactor vessel.

[0032] In some embodiments, the reactor also includes a primary lead-bismuth system, and the heat exchange tube 20 extends to the primary lead-bismuth system, so that a portion of the heat exchange tube 20 serving as the heat exchange body directly contacts the lead-bismuth liquid of the primary lead-bismuth system and exchanges heat to generate steam, thereby further facilitating the arrangement of the steam generator in the channel of the upper stack cover of the stack container.

[0033] The operation process of the steam generator of the present application in a lead-bismuth fast reactor is further described below with reference to specific embodiments.

[0034] Cold water of the secondary cooling system enters the first chamber 11 from the cold water inlet 111 of the first chamber 11, and enters the second heat exchange tube body 22 through the first through hole 31, flows to the lower end of the second heat exchange tube body 22 under the action of gravity, enters the first heat exchange tube body 21 to exchange heat with the high-temperature liquid lead bismuth of the primary lead-bismuth system, and generates steam; under the action of continuous input of cold water into the second heat exchange tube body 22, the high-temperature liquid lead bismuth is continuously cooled and flows from top to bottom along the outside of the first heat exchange tube body 21, the cold water absorbs heat and is continuously vaporized into steam, the steam gradually accumulates and flows upward along the first heat exchange tube body 21, and continues to exchange heat with the high-temperature liquid lead bismuth during the rising process, becoming slightly superheated steam, the slightly superheated steam enters the second chamber 12 through the second through hole 41, and flows out of the second chamber 12 from the steam outlet 121, and enters the secondary circuit.

[0035] Regarding the embodiments of the present application, it should also be noted that, in the absence of conflict, the embodiments of the present application and the features therein can be combined with each other to obtain new embodiments.

[0036] The above are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. The protection scope of the present application shall be based on the protection scope of the claims.

Claims

1. A steam generator for a lead-bismuth fast reactor, characterized in that: It includes: Body, heat exchange tube, The body is configured to form a first chamber and a second chamber therein, A cold water inlet is formed at the position of the first chamber of the body, a steam outlet is formed at the position of the second chamber of the body, the heat exchange tube is in fluid communication with the first chamber, a portion of the heat exchange tube is disposed in the second chamber, and the other portion is extended to pass through the second chamber into the primary lead-bismuth liquid. Wherein, cold water enters the first chamber from the cold water inlet and flows into the heat exchange tube, and the steam generated after heat exchange in the heat exchange tube flows out from the steam outlet.

2. The steam generator according to claim 1, characterized in that: Also includes: A first plate and a second plate, wherein the first plate and the second plate are arranged to be fixedly connected to the main body, and the main body and the first plate form the first chamber, and the first plate, the main body and the second plate form the second chamber.

3. The steam generator according to claim 1, characterized in that: The heat exchange tube comprises a first heat exchange tube body and a second heat exchange tube body, a portion of the second heat exchange tube body is arranged inside the first heat exchange tube body, The lower end of the first heat exchange tube body is closed, and the lower end of the second heat exchange tube body is open; The upper end of the first heat exchange tube body is in fluid communication with the second chamber, and a portion of the second heat exchange tube body extending in the second chamber is disposed outside the first heat exchange tube body.

4. The steam generator according to claim 3, characterized in that: The second heat exchange tube body is subjected to heat insulation treatment to reduce heat exchange between the fluid inside the second heat exchange tube body and the fluid in the first heat exchange tube body.

5. The steam generator according to claim 4, characterized in that: A heat insulation layer is formed inside the second heat exchange tube body.

6. The steam generator according to any one of claims 3 to 5, characterized in that: The first heat exchange tube body and the second heat exchange tube body are arranged radially concentrically.

7. A reactor, characterized in that: The reactor comprises the steam generator according to any one of claims 1-6.

8. The reactor according to claim 7, characterized in that It also includes a stack container and a stack cover, wherein the stack cover is arranged on the stack container and a hole is arranged on the stack cover. The steam generator is arranged in the duct.

9. The reactor according to claim 8, characterized in that It also includes a secondary cooling system, the first chamber is in fluid communication with the secondary cooling system, and cold water from the secondary cooling system flows into the first chamber from a cold water inlet of the first chamber.

10. The reactor according to claim 9, characterized in that It also includes a primary lead-bismuth system, and the heat exchange tube extends to the primary lead-bismuth system.

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