Device suitable for removing activation product 210Po in protective gas of lead-bismuth cooled reactor and lead-bismuth cooled reactor

Abstract

The embodiment of the invention relates to the technical field of radioactive gas treatment, in particular to a device suitable for removing an activation product 210Po in protective gas of a lead-bismuth cooled reactor and the lead-bismuth cooled reactor. The removing device comprises a shell, a 210Po dissolving solution, a gas inlet pipeline and a gas outlet pipeline. The shell is arranged to form a containing cavity. The < 210 > Po dissolving solution is arranged in the accommodating cavity and is used for dissolving < 210 > Po entering the accommodating cavity. The gas inlet pipeline is used for introducing the protective gas in the gas cavity of the lead-bismuth cooling reactor below the liquid level of the 210Po dissolving solution, so that 210Po in the protective gas is removed by utilizing the 210Po dissolving solution. And the gas outlet pipeline is used for circularly returning the protective gas which is positioned above the liquid level of the 210Po dissolving solution and is subjected to 210Po removal to the gas cavity of the lead-bismuth cooling reactor. According to the removal device disclosed by the embodiment of the invention, the protective gas is led out of the reactor container to remove < 210 > Po in the protective gas, and compared with removal of < 210 > Po in a lead-bismuth coolant, the removal device has the advantages that the technological process is simplified, and the implementation difficulty is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of treating radioactive gases, and in particular to a method for removing activation products in the protective gas of a lead-bismuth cooled reactor. 210 Po device and lead-bismuth cooled reactor. Background Art

[0002] This section of content merely provides background information related to the present application and does not necessarily constitute prior art.

[0003] Lead-bismuth cooled reactors have become an important development direction for global energy supply due to their high energy density and good inherent safety. However, during the operation of the reactor, the lead-bismuth coolant 209 Bi reacts easily with neutrons to produce 210 Bi, 210 Bi will then decay through β to form 210 Po. 210 Po is an extremely toxic and volatile substance with a half-life of up to 138 days. 210 During the decay process, Po will release alpha particles, causing internal radiation, which will bring serious harm. Under accident conditions, the increase in the temperature of the top protective gas will also lead to 210 The release of Po increases, and there is a risk of exceeding international safety standards. With the increasing application of lead-bismuth cooled reactors, how to remove the lead-bismuth cooled reactors? 210 Po has become a problem that needs to be solved. Summary of the invention

[0004] 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.

[0005] In view of the above technical problems, the embodiments of the present application provide a method for removing activation products in the protective gas of a lead-bismuth cooled reactor. 210 Po device and lead-bismuth cooled reactor.

[0006] In a first aspect, the embodiments of the present application provide a method for removing activation products in a protective gas of a lead-bismuth cooled reactor. 210 The device of Po may include a housing, 210 Po solution, an air inlet pipeline and an air outlet pipeline. The shell is configured to form a receiving cavity. 210 Po dissolving liquid is arranged in the containing chamber, and is used to make the210 The air inlet pipe is used to introduce the protective gas into the gas cavity of the lead-bismuth cooling reactor. 210 Po solution below the liquid surface, in order to use 210 Po dissolved liquid removes the protective gas 210 Po. The outlet pipe is used to 210 Removal of the surface of the Po solution 210 The protective gas after Po is circulated back to the gas cavity of the lead-bismuth cooled reactor.

[0007] The invention relates to a method for removing activation products from the protective gas of a lead-bismuth cooling reactor according to an embodiment of the present invention. 210 The Po device introduces the protective gas in the gas cavity of the reactor into the housing cavity of the shell through the air inlet pipeline. 210 Below the liquid surface of the Po solution, the 210 Po dissolved liquid removes the protective gas 210 Po, and then through the outlet pipe to 210 Removal of the surface of the Po solution 210 The protective gas after Po is circulated back to the gas cavity of the lead-bismuth cooling reactor, so that the protective gas can be led out of the reactor container to remove the protective gas. 210 Po, compared to the removal of lead bismuth coolant 210 Po, the embodiment of the present application has a certain effect on the protective gas 210 Po is removed, which simplifies the process and reduces the difficulty of implementation.

[0008] In a second aspect, an embodiment of the present application provides a lead-bismuth cooled reactor, which may include a reactor container, a core assembly, a heat exchanger, a flow distributor, a current collector, and a pump. The reactor container may include a container body with an opening formed at the top and a reactor top cover for closing the container body, the container body is used to accommodate the lead-bismuth coolant, and an air cavity is formed above the lead-bismuth coolant liquid level, and the air cavity is filled with a protective gas. The core assembly is arranged in the container body. The heat exchanger is used to receive the lead-bismuth coolant from the core assembly and cool it. The flow distributor is arranged below the core assembly for supplying the lead-bismuth coolant into the core assembly. The current collector is arranged to form a current collector cavity, and the current collector is arranged radially outside the flow distributor for receiving the lead-bismuth coolant cooled by the heat exchanger. The pump is used to pump the lead-bismuth coolant in the current collector to the upper part of the container body, so that the lead-bismuth coolant from the current collector flows downward, and flows downward to the bottom of the current collector on the radial outside of the current collector, and finally enters the flow distributor.

[0009] In a third aspect, an embodiment of the present application provides a lead-bismuth cooled reactor, which may include a reactor container and an activation product in a protective gas for removing the lead-bismuth cooled reactor provided in the first aspect of the present application. 210The stack container may include a container body with an opening formed on the top and a stack cover for closing the container body, the container body is used to contain the lead-bismuth coolant, an air cavity is formed above the lead-bismuth coolant liquid level, and the air cavity is filled with a protective gas. The removal device is arranged above the stack cover to remove the activation product in the protective gas. 210 Po.

[0010] These and other advantages of the present application will become more apparent through the following detailed description of the preferred embodiments of the present application in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] In order to further illustrate the above and other advantages and features of the present application, the specific embodiments of the present application are further described in detail below in conjunction with the accompanying drawings. The accompanying drawings together with the following detailed description are included in this specification and form a part of this specification. Elements with the same function and structure are represented by the same reference numerals. It should be understood that these drawings only describe typical examples of the present application and should not be regarded as limiting the scope of the present application.

[0012] Figure 1 According to one embodiment of the present application, it is suitable for removing the activation product in the protective gas of the lead-bismuth cooling reactor. 210 A schematic diagram of the structure of Po's device;

[0013] Figure 2 is a schematic diagram of a lead-bismuth cooled reactor according to an embodiment of the present application, wherein the dotted line in the reactor container shows the liquid level of the lead-bismuth coolant;

[0014] Figure 3 is a schematic structural diagram of a gas dispersion component according to an embodiment of the present application;

[0015] Figure 4 It is a schematic diagram of a lead-bismuth cooled reactor according to another embodiment of the present application, wherein the arrows in the reactor container indicate the flow direction of the lead-bismuth coolant, and the dotted line in the reactor container indicates the liquid level of the lead-bismuth coolant.

[0016] 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.

[0017] Description of reference numerals:

[0018] 10. 210 Po removal device; 11, housing; 101, accommodating chamber; 102, 210Liquid level of Po solution; 12, air inlet pipeline; 121, air inlet end; 122, air outlet end; 13, air outlet pipeline; 131, air inlet end; 132, air outlet end; 14, gas dispersion member; 141, partition; 142, hollow hole; 15, fan; 16, base; 161, bottom plate; 162, pipe seat; 17, reinforcement plate;

[0019] 20. stack container; 21. container body; 22. stack top cover; 201. air cavity;

[0020] 30. Core assembly;

[0021] 40. heat exchanger; 41. heat exchange inlet; 42. heat exchange outlet; 43. heat exchanger shell;

[0022] 50. Flow distribution parts;

[0023] 60. Current collecting parts;

[0024] 70. Pump; 71. Pump inlet; 72. Pump outlet; 73. Pump casing;

[0025] 81. a first flow guide; 82. a second flow guide;

[0026] 91. Protective cover; 92. Stack top shield. DETAILED DESCRIPTION

[0027] 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.

[0028] 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.

[0029] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in this application should have the common meanings understood by persons with ordinary skills in the field to which this application belongs.

[0030] In the description of the embodiments of the present application, “plurality” means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0031] In the related art, the lead-bismuth coolant in the stack container is usually 210 For example, in a lead-bismuth cooled reactor, a 210 Po removal device to remove the lead-bismuth coolant 210 Po removal device to utilize 210 Po removal device for lead-bismuth coolant 210 The inventors of the present application have found that directly removing the lead-bismuth coolant 210 The removal of Po has the problems of high process requirements and great difficulty in implementation.

[0032] In order to solve the above technical problems, the embodiment of the present application provides a method for removing the activation products in the protective gas of the lead-bismuth cooled reactor. 210 Po device (hereinafter referred to as 210 Po removal device).

[0033] See also Figure 1 and Figure 2 , Figure 1 According to an embodiment of the present application 210 Schematic diagram of the structure of the Po removal device, Figure 2 is a schematic diagram of a lead-bismuth cooled reactor according to an embodiment of the present application, wherein the dotted line in the reactor container 20 shows the liquid level of the lead-bismuth coolant. 210 The Po removal device 10 may include a housing 11, 210 Po solution, an air inlet pipe 12 and an air outlet pipe 13. The housing 11 is configured to form a receiving chamber 101. 210 The Po dissolving liquid is disposed in the containing chamber 101, and is used to dissolve the Po in the containing chamber 101. 210 The air inlet pipe 12 is used to introduce the protective gas in the lead-bismuth cooling reactor air cavity 201 into the 210 Po solution below the liquid level 102, in order to utilize 210 Po dissolved liquid removes the protective gas 210 Po. The air outlet pipe 13 is used to 210 Removal of the liquid surface 102 of the Po solution 210 The protective gas after Po is circulated back to the gas cavity 201 of the lead-bismuth cooled reactor.

[0034] In the embodiment of the present application, the protective gas in the gas cavity 201 in the stack is introduced into the accommodating cavity 101 of the shell 11 through the gas inlet pipeline 12. 210 Below the liquid level of the Po solution, the210 Po dissolved liquid removes the protective gas 210 Po, and then through the outlet pipe 13 210 Removal of the surface of the Po solution 210 The protective gas after Po is circulated back to the gas cavity 201 of the lead-bismuth cooling reactor, so that the protective gas can be led out of the reactor container to remove the protective gas. 210 Po. Compared with the removal of lead bismuth coolant 210 Po, the embodiment of the present application has a certain effect on the protective gas 210 Po is removed, which simplifies the process and reduces the difficulty of implementation.

[0035] Easy to understand, 210 Po removal device 10 210 Po solution does not fill the containing chamber 101, 210 The liquid surface 102 of the Po solution can be filled with a gas having the same composition as the protective gas. 210 During the operation of the Po removal device 10, the protective gas is continuously introduced into the containing chamber 101 through the air inlet pipe 12. 210 Below the liquid level 102 of the Po solution, the protective gas flows out from the outlet end of the air inlet pipe 12 and flows upward. 210 Po 210 Po dissolves and removes 210 The shielding gas after Po will continue to flow to 210 Po solution liquid level 102 above. 210 When a certain amount of protective gas accumulates above the liquid level 102 of the Po solution, the protective gas will be sent back to the air cavity 201 of the lead-bismuth cooling reactor along the gas outlet pipeline 13. 210 A circulating flow is formed between the Po removal devices 10, thereby achieving continuous purification and recycling of the protective gas in the lead-bismuth cooled reactor.

[0036] See also Figure 2 In some embodiments, the air inlet end 121 of the air inlet pipeline 12 is located in the air cavity 201 of the lead-bismuth cooled reactor, and the air cavity 201 in the reactor contains 210 The protective gas of Po can enter the accommodating chamber 101 through the inlet end 121 of the inlet pipeline 12. The outlet end 122 of the inlet pipeline 12 is located at 210 The liquid level 102 of the Po solution is below the bottom wall of the containing chamber 101, so as to maximize the protective gas 210 The upward movement path of Po in the solution increases 210 Po solution 210 The dissolution time of Po increases 210The dissolution effect of Po.

[0037] In some embodiments, the air inlet end 131 of the air outlet pipe 13 is located at 210 The outlet end 132 of the outlet pipe 13 is located in the air cavity 201 of the lead-bismuth cooling reactor, which is conducive to removing the 210 The protective gas after Po returns to the gas cavity 201 of the lead-bismuth cooled reactor.

[0038] In some embodiments, the shielding gas may be argon.

[0039] In some embodiments, the air inlet pipe 12 and the air outlet pipe 13 may be connected to the housing 11 through nuts and sealing washers, so as to facilitate both disassembly and sealing. The housing 11 may be a cylinder.

[0040] In some embodiments, the air inlet pipe 12 , the air outlet pipe 13 and the housing 11 may be made of stainless steel to enhance corrosion resistance.

[0041] The inventors of the present application discovered that 210 Po is easily soluble in nitric acid solution. Therefore, in some embodiments, 210 The Po dissolving liquid can be dilute nitric acid. The inventors of the present application have found that dilute nitric acid can be used to remove the 210 Po, will not introduce impurities into the shielding gas.

[0042] In some embodiments, 210 The concentration of the Po solution can be 2-8%. The inventors of the present application have found that this arrangement is more conducive to improving 210 The dissolution efficiency of Po solution is improved 210 Po solution 210 The dissolution effect of Po.

[0043] See also Figure 1 , in some embodiments, 210 The Po removal device 10 may further include a gas dispersion member 14. The gas dispersion member 14 is disposed at the lower portion of the accommodating chamber 101, and the outlet end 122 of the air inlet pipeline 12 is located below the gas dispersion member 14. The gas dispersion member 14 is used to disperse the protective gas flowing out of the outlet end 122 of the air inlet pipeline 12, so that the dispersed protective gas flows upward to the 210 The liquid level 102 of the Po solution is above this. This arrangement is beneficial to increase the protective gas 210 The length of time that Po stays in the solution is beneficial to keep the protective gas as close to the 210 Po solution contact, improve 210 Po solution 210 The dissolution effect of Po.

[0044] The gas dispersion element 14 is provided to disperse the protective gas from the gas outlet end 122 of the gas inlet pipeline 12 into a plurality of small bubbles. 210 Po rises in the dissolved liquid, which is beneficial to increase the protective gas and 210 The contact time of Po solution is beneficial to improve 210 Dissolution efficiency of Po.

[0045] In some embodiments, the gas dispersion member 14 is a hollow frame. The hollow frame can evenly disperse the protective gas, so that the protective gas rises through the hollow frame in the form of fine bubbles, which is beneficial to increase the protective gas and 210 At the same time, since the protective gas is dispersed into small bubbles by the hollow frame, the rising speed is slowed down, which is beneficial to increase the contact area of ​​the protective gas in 210 The length of time that Po stays in the solution further increases 210 Po solution 210 The dissolution effect of Po.

[0046] See also Figure 3 , Figure 3 1 is a schematic diagram of the structure of a gas dispersion member 14 according to an embodiment of the present application. In some embodiments, the hollow frame is composed of crisscrossed partitions 141, the width of the partition 141 is 5 to 10 mm, and the size of the hollow hole 142 formed between two adjacent partitions 141 is 5 to 10 mm. This arrangement is more conducive to improving the dispersion effect of the gas dispersion member 14 on the protective gas.

[0047] In some embodiments, the gas dispersion member 14 may be welded to the housing 11 to enhance the stability of the gas dispersion member 14 .

[0048] See also Figure 1 and Figure 2 , in some embodiments, 210 The Po removal device 10 may also include a base 16, which is installed outside the stack container 20, and the housing 11 is plugged with the base 16. The base 16 can be connected to the stack top cover 22 through nuts and gaskets. 210 When the Po solution is dissolved, the housing 11 can be directly lifted from the base 16. Since the gas dispersion member 14 is welded to the housing 11, the housing 11 can be 210 The Po solution and the gas dispersion member 14 are replaced as a whole.

[0049] In some embodiments, the base 16 may include a bottom plate 161 and a tube seat 162 connected to the bottom plate 161 , wherein the tube seat 162 forms a slot that matches the shape of the shell 11 , and the bottom of the shell 11 is inserted into the slot.

[0050] See also Figure 1 and Figure 2 , in some embodiments, 210 The Po removal device 10 may further include a reinforcing plate 17, which is used to connect the tube seat 162 and the bottom plate 161, thereby facilitating the reinforcement. 210 The stability of the Po removal device 10.

[0051] See also Figure 1 and Figure 2 , in some embodiments, 210 The Po removal device 10 may further include a fan 15. The fan 15 is disposed in the air inlet pipeline 12 and is used to drive the protective gas in the air cavity 201 of the lead-bismuth cooling reactor to enter the air cavity 201 through the air inlet pipeline 12. 210 The Po solution is below the liquid level 102. In this embodiment, the fan 15 is arranged in the air intake pipeline 12, which provides a flow power for the protective gas in the air intake pipeline 12, which is conducive to the protective gas entering the 210 The liquid level 102 of the Po solution is below the liquid level 102, thereby helping to improve the protective gas and 210 Contact efficiency of Po solution.

[0052] In some embodiments, the flow rate of the fan 15 can be 0.04-0.06 L / s, for example 0.05 L / s. The inventors of the present application have found that such an arrangement can allow the protective gas to enter the air chamber at an appropriate rate. 210 The Po solution is below the liquid level 102, thereby preventing the protective gas from contacting the protective gas due to excessive flow rate or excessive bubbles. 210 Insufficient contact with the Po solution is conducive to improving 210 Removal efficiency of Po.

[0053] The embodiment of the present application also provides a lead-bismuth cooled reactor, which may include a reactor container 20 and any one of the embodiments of the present application. 210 Po removal device 10. The stack container 20 includes a container body 21 with an opening formed on the top and a stack cover 22 for closing the container body 21. The container body 21 is used to contain the lead-bismuth coolant. An air cavity 201 is formed above the liquid level of the lead-bismuth coolant, and the air cavity 201 is filled with a protective gas. 210 The Po removal device 10 is arranged above the stack top cover 22 and is used to remove the activation products in the protective gas. 210 Po. The embodiments of the present application are 210 Po removal device 10 for protecting gas 210 Po is removed, which simplifies the process and reduces the difficulty of implementation.

[0054] The embodiment of the present application also provides a lead-bismuth cooled reactor. Figure 4 , Figure 4Schematic diagram of a lead-bismuth cooled reactor according to another embodiment of the present application, wherein the arrow in the reactor container shows the flow direction of the lead-bismuth coolant, and the dotted line in the reactor container shows the liquid level of the lead-bismuth coolant. The embodiment of the present application provides that the lead-bismuth cooled reactor may include a reactor container 20, a core assembly 30, a heat exchanger 40, a flow distributor 50, a current collector 60, and a pump 70. The reactor container 20 may include a container body 21 with an opening formed at the top and a reactor top cover 22 for closing the container body 21, the container body 21 is used to accommodate the lead-bismuth coolant, and an air cavity 201 is formed above the liquid level of the lead-bismuth coolant, and the air cavity 201 is filled with a protective gas. The core assembly 30 is arranged in the container body 21. The heat exchanger 40 is used to receive the lead-bismuth coolant from the core assembly 30 and cool it. The flow distributor 50 is arranged below the core assembly 30 for supplying the lead-bismuth coolant into the core assembly 30. The current collecting member 60 is configured to form a current collecting cavity, and the current collecting member 60 is disposed radially outside the flow distributor 50, and is used to receive the lead-bismuth coolant after cooling by the heat exchanger 40. The pump 70 is used to pump the lead-bismuth coolant in the current collecting member 60 to the upper part of the container body 21, so that the lead-bismuth coolant from the current collecting member 60 flows downward, and flows downward radially outside the current collecting member 60 to the bottom of the current collecting member 60, and finally enters the flow distributor 50.

[0055] In the lead-bismuth cooled reactor provided by the embodiment of the present application, the lead-bismuth coolant flowing out from the core assembly 30 directly enters the heat exchanger 40, is cooled in the heat exchanger 40, and then flows directly from the inside of the heat exchanger 40 to the collecting piece 60, and then the lead-bismuth coolant is delivered to the upper part of the reactor vessel 20 body by the pump 70, and then the lead-bismuth coolant flows downward along the outer side of the collecting piece 60 to the bottom, and then re-enters the core assembly 30 evenly through the flow distribution piece 50, and continues to circulate in this way, which is more conducive to the circulation of the lead-bismuth coolant inside the reactor.

[0056] The current collecting member 60 is an annular structure, and the current collecting cavity formed by the current collecting member 60 is an annular current collecting cavity.

[0057] In some embodiments, the heat exchanger 40 includes a heat exchanger shell 43, a heat exchange inlet portion 41 and a heat exchange outlet portion 42. A heat exchange cavity for flow of lead-bismuth coolant is formed in the heat exchanger shell 43. The heat exchange inlet portion 41 forms a heat exchange inlet connected to the heat exchange cavity. The heat exchange outlet portion 42 forms a heat exchange outlet connected to the heat exchange cavity. The lead-bismuth coolant flowing through the core assembly 30 enters the heat exchange cavity through the heat exchange inlet, exchanges heat with the heat exchange medium, and then flows into the collecting cavity of the collecting member 60 from the heat exchange outlet.

[0058] In some embodiments, the heat exchange outlet portion 42 is formed at the bottom of the heat exchanger shell 43 ; the heat exchange inlet portion 41 is formed at the side of the heat exchanger shell 43 and faces the core assembly 30 .

[0059] In some embodiments, the current collector 60 has a current collector inlet and a current collector outlet communicating with the current collector cavity, and the heat exchange outlet portion 42 is connected to the current collector inlet of the current collector 60, so that the lead-bismuth coolant after heat exchange with the heat exchange medium in the heat exchange cavity directly enters the current collector cavity, and does not enter the container body 21. This arrangement allows the cooled lead-bismuth coolant to be collected in the current collector cavity.

[0060] In some embodiments, the reactor may further include a top shield 92. The top shield 92 is disposed below the top cover 22 and directly above the core assembly 30. In some embodiments, the top shield 92 may include a thermal shield layer and a neutron shield layer, which are used to reduce heat transfer and shield neutrons in the reactor, respectively.

[0061] The heat exchange inlet 41 may extend from the heat exchanger shell 43 to below the top shield 92 and be close to the lower surface of the top shield 92. In some embodiments, the reactor may further include a core shroud, and the core assembly 30 is disposed in the core shroud. The core shroud is connected to the heat exchange inlet 41, and the core shroud is provided with a liquid outlet communicating with the heat exchange inlet, and the lead-bismuth coolant flowing out of the core assembly 30 flows directly to the heat exchange inlet through the liquid outlet.

[0062] In some embodiments, the pump 70 includes a pump housing 73, a pump inlet 71, and a pump outlet 72. A pump chamber for the lead-bismuth coolant to flow is formed in the pump 70. The pump inlet 71 forms a pump inlet communicating with the pump chamber, and the pump outlet 72 forms a pump outlet communicating with the pump chamber. The lead-bismuth coolant from the manifold enters the pump chamber through the pump inlet and flows into the container body 21 from the pump outlet.

[0063] In some embodiments, the pump inlet 71 is formed at the bottom of the pump housing 73 ; the pump outlet 72 is formed at the side of the pump housing 73 and faces away from the core assembly 30 .

[0064] In some embodiments, the pump inlet 71 is connected to the current collecting outlet of the current collecting member 60, so that the lead-bismuth coolant in the current collecting cavity directly enters the pump chamber without entering the container body 21. This arrangement allows the cooled lead-bismuth coolant to be pumped to the pump outlet 72 by the pump 70, thereby improving the circulation effect of the lead-bismuth coolant and thus improving the cooling effect on the core assembly 30.

[0065] In some implementations, the heat exchanger housing 43 of the heat exchanger 40 and the pump housing 73 of the pump 70 are respectively connected to the stack top cover 22 .

[0066] In some embodiments, the reactor may further include a first flow guide 81 and a second flow guide 82. The first flow guide 81 is disposed at the bottom of the container body 21 directly below the flow distributor 50. The second flow guide 82 is disposed at the bottom of the current collector 60 to guide the lead-bismuth coolant. In this embodiment, the flow path of the lead-bismuth coolant is effectively guided by providing the first flow guide 81 and the second flow guide 82, which is beneficial for the lead-bismuth coolant at the bottom of the container body 21 to flow to the core assembly 30, thereby improving the circulation efficiency of the lead-bismuth coolant.

[0067] In some embodiments, the lower surface of the first guide member 81 may be a curved surface, so as to facilitate guiding the lead-bismuth coolant at the bottom of the container body 21 to flow toward the second guide member 82. In some embodiments, the upper surface of the second guide member 82 may be a curved surface, so as to facilitate guiding the lead-bismuth coolant to the flow distribution member 50.

[0068] In some embodiments, the first flow guide 81 may be connected to the lower surface of the flow collector 60. The first flow guide 81 is an annular structure, and its ring width is the same as that of the flow collector 60, and its radial outer diameter and radial inner diameter are the same, that is, the inner diameter of the first flow guide 81 is the same as the diameter of the flow distributor 50.

[0069] The diameter of the second flow guide 82 is greater than the diameter of the flow distributor 50 , so that the second flow guide 82 partially overlaps with the first flow guide 81 in the radial direction of the container body 21 , thereby being more conducive to guiding the lead-bismuth coolant at the bottom of the container body 21 to the flow distributor 50 .

[0070] In some embodiments, there are two heat exchangers 40, which are symmetrically arranged on both radial sides of the core assembly 30. In some embodiments, there are two pumps 70, which are symmetrically arranged on both radial sides of the core assembly 30 and are respectively located radially outside the two heat exchangers 40. The heat exchange outlet 42 of each heat exchanger 40 and the pump inlet 71 of each pump 70 are connected to the manifold 60, so that the lead-bismuth coolant flowing out of the heat exchange cavity of each heat exchanger 40 can directly enter the manifold cavity and be pumped into the pump casing 73.

[0071] Since the temperature in the core assembly 30 is relatively high, the lead-bismuth coolant easily forms aerosol after absorbing the heat of the core assembly 30 and rises to the reactor top cover 22. Therefore, in some embodiments, the reactor may further include a protective cover 91. The protective cover 91 is used to form a closed negative pressure space above the reactor top cover 22, thereby preventing the leakage of radioactive aerosol.

[0072] In some embodiments, the reactor may also include any of the embodiments of the present application. 210 The Po removal device 10 is arranged above the stack top cover 22 and is used to remove the activation products in the protective gas. 210 Po.210 The Po removal device 10 is arranged above the stack top cover 22, so that the protective gas in the lead-bismuth cooling reactor can be removed outside the stack container 20. 210 Po treatment, compared with the removal of lead bismuth coolant 210 Po, simplifies the process and reduces the difficulty of implementation.

[0073] Calculations show that without setting 210 In the lead-bismuth cooled reactor of the Po removal device 10, the lead-bismuth medium is activated and produced 210 Po, reaches saturation in about the third year, with a saturation activity of 3E+15Bq, and migrates to the protective gas 210 The saturated activity value of Po is 1.0E+0.5Bq, and the saturated specific activity is 6.0E+0.1a / L. According to the ventilation volume of 2000L / h in the protective cover 91 and the leakage rate of 2L / d in the pile cover 22, the specific activity of the radioactivity in the protective cover 91 is 1.0E-0.4Bq / L. If the removal efficiency can reach 90%, the specific activity of the radioactivity in the protective cover 91 can be reduced to 1.0E-0.5Bq / L. From the above calculation results, it can be seen that by setting 210 The Po removal device 10 can effectively reduce the radioactivity specific activity in the protective cover 91 .

[0074] 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.

[0075] The above description is only a specific implementation manner 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 method for removing activation products from the protective gas of a lead-bismuth cooled reactor 210 The device of Po is characterized in that The device comprises: a housing, the housing being configured to form a receiving cavity; 210 Po dissolving liquid is arranged in the containing cavity, and is used to make the 210 Po dissolution; The air inlet pipeline is used to introduce the protective gas in the lead-bismuth cooling reactor gas cavity into the 210 Po solution below the liquid surface, in order to utilize the 210 Po dissolved liquid removes the protective gas 210 Po; The outlet pipe is used to 210 Removal of the surface of the Po solution 210 The protective gas after Po is circulated back to the gas cavity of the lead-bismuth cooled reactor.

2. The device according to claim 1, characterized in that Said 210 The Po dissolving solution is dilute nitric acid.

3. The device according to claim 2, characterized in that Said 210 The concentration of the Po solution is 2 to 8%.

4. The device according to claim 1, characterized in that Also includes: A gas dispersion member is arranged at the lower part of the accommodating cavity, the outlet end of the air inlet pipeline is located below the gas dispersion member, and the gas dispersion member is used to disperse the protective gas flowing out of the outlet end of the air inlet pipeline so that the dispersed protective gas flows upward to the 210 Po above the liquid surface of the solution.

5. The device according to claim 4, characterized in that The gas dispersion member is a hollow frame.

6. The device according to claim 5, characterized in that The hollow frame is composed of crisscross partitions, the width of the partition is 5-10 mm, and the size of the hollow hole formed between two adjacent partitions is 5-10 mm.

7. The device according to claim 4, characterized in that Also includes: A fan is arranged in the air inlet pipeline, and is used to drive the protective gas in the air cavity of the lead-bismuth cooling reactor to enter the 210 Below the liquid surface of the Po solution.

8. A lead-bismuth cooled reactor, characterized in that: include: A stack container, the stack container comprising a container body with an opening formed on the top and a stack cover for closing the container body, the container body is used to contain a lead-bismuth coolant, an air cavity is formed above the liquid level of the lead-bismuth coolant, and the air cavity is filled with a protective gas; A core assembly is disposed in the container body; a heat exchanger for receiving and cooling the lead-bismuth coolant from the core assembly; A flow distribution member, disposed below the core assembly, for supplying lead-bismuth coolant into the core assembly; A current collecting member, arranged to form a current collecting cavity, the current collecting member being arranged radially outside the flow distribution member and used for receiving the lead-bismuth coolant after being cooled by the heat exchanger; A pump is used to pump the lead-bismuth coolant in the current collecting piece to the upper part of the container body, so that the lead-bismuth coolant from the current collecting piece flows downward, flows downward on the radial outside of the current collecting piece to the bottom of the current collecting piece, and finally enters the flow distribution piece.

9. The reactor according to claim 8, characterized in that Also includes: A protective cover is used to form a closed negative pressure space above the stack top cover.

10. A lead-bismuth cooled reactor, characterized in that: include: A stack container, the stack container comprising a container body with an opening formed on the top and a stack cover for closing the container body, the container body is used to contain a lead-bismuth coolant, an air cavity is formed above the liquid level of the lead-bismuth coolant, and the air cavity is filled with a protective gas; The method according to any one of claims 1 to 7 for removing activation products in the protective gas of a lead-bismuth cooled reactor 210 A Po device is provided above the stack top cover to remove the activation products in the protective gas. 210 Po.

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