Marine secondary side waste heat removal system based on natural circulation and forced circulation operation

Abstract

The invention relates to a marine secondary side waste heat removal system based on natural circulation and forced circulation operation, and relates to the technical field of special safety of a marine nuclear power system, the marine secondary side waste heat removal system comprises a reactor pressure vessel, and a steam generator is arranged on one side of the reactor pressure vessel; a first circulation pipeline is arranged between the steam generator and the reactor pressure vessel, a cooling assembly is arranged on one side of the steam generator, and a steam generator secondary side waste heat removal system pipeline is arranged between the steam generator and the cooling assembly. Heat of the steam generator is led out to the cooling water tank through natural circulation established by the density difference of the steam phase and the liquid phase, in addition, the forced circulation assembly is arranged between the cooling assembly and the steam generator secondary side waste heat discharging system pipeline, and the circulation capacity of the steam generator secondary side waste heat discharging system pipeline can be enhanced through the forced circulation assembly. The secondary side waste heat removal system has the advantage that the heat removal capacity of the secondary side waste heat removal system is improved on the premise of not depending on external energy.

Description

Technical Field

[0001] The present application relates to the field of special safety technology for ship nuclear power systems, and in particular to a ship secondary side waste heat removal system based on natural circulation and forced circulation operation. Background Art

[0002] In order to cope with power outages in the entire plant or ship (including loss of emergency power) and failure of the auxiliary water supply system pneumatic pump series, advanced nuclear power plants such as APR1400, KLT-40S, and Hualong One have all adopted a secondary side passive residual heat removal system solution that arranges passive residual heat removal coolers in high-level water tanks and uses the boiling evaporation of water stored in the water tanks to extract the core decay heat. The heat removal capacity of the passive residual heat removal system is closely related to the natural circulation flow rate. The larger the flow rate, the stronger the heat removal capacity of the system. However, for the residual heat removal system, the heat exchange capacity of the forced circulation is stronger than that of the natural circulation. Summary of the invention

[0003] In order to improve the heat removal capacity of the secondary side waste heat removal system without relying on external energy, the present application provides a marine secondary side waste heat removal system based on natural circulation and forced circulation operation.

[0004] The present application provides a marine secondary side waste heat removal system based on natural circulation and forced circulation operation, which adopts the following technical solutions:

[0005] A marine secondary side waste heat removal system based on natural circulation and forced circulation operation includes a steam generator, a cooling component is arranged on one side of the steam generator, a steam generator secondary side waste heat removal system pipeline is arranged between the steam generator and the cooling component, the steam generator secondary side waste heat removal system pipeline exchanges the temperature of the cooling component and the steam generator, a forced circulation component is arranged between the cooling component and the steam generator secondary side waste heat removal system pipeline, and the forced circulation component enhances the circulation capacity of the steam generator secondary side waste heat removal system pipeline.

[0006] Optionally, the cooling component includes a cooling water tank, a waste heat discharge cooler is arranged inside the cooling water tank, the waste heat discharge cooler is connected to the waste heat discharge system pipeline on the secondary side of the steam generator, and the waste heat discharge system pipeline on the secondary side of the steam generator is connected to the forced circulation component.

[0007] Optionally, the steam generator secondary side waste heat discharge system pipeline includes a medium flow pipe, the steam generator includes a first heat exchange inlet and a first heat exchange outlet, the waste heat discharge cooler includes a second heat exchange inlet and a second heat exchange outlet, the medium flow pipe connects the first heat exchange outlet with the second heat exchange inlet, and the medium flow pipe connects the first heat exchange inlet with the second heat exchange outlet.

[0008] Optionally, the forced circulation component includes a power supply component, the input end of the power supply component is provided with a fan blade, the cooling water tank is provided with a nozzle at one end opposite to the fan blade, the nozzle is opposite to the blade of the fan blade, when the nozzle is turned on, the medium inside the nozzle drives the fan blade to rotate, and a circulation pump is provided on the pipeline of the waste heat discharge system on the secondary side of the steam generator, and the power supply component supplies power to the circulation pump.

[0009] Optionally, a forced circulation pipeline is provided on the steam generator secondary side waste heat removal system pipeline, the circulation pump is located on the forced circulation pipeline, the medium flow pipeline is provided with a second control valve relative to the forced circulation pipeline, and the forced circulation pipeline is provided with a first control valve.

[0010] Optionally, the internal opening of the nozzle gradually decreases from the side away from the fan blade to the side close to the fan blade, and the nozzle is provided with a first control valve for controlling the flow of the internal medium.

[0011] Optionally, the power generation component includes a generator, a battery is provided on one side of the generator, the rotation of the fan blades drives the generator to generate electricity, and the electricity generated by the generator is input into the battery for storage.

[0012] Optionally, a pressure relief valve is fixedly connected to the top of the cooling water tank.

[0013] In summary, the present application includes at least one of the following beneficial technical effects:

[0014] 1. Under the premise of not relying on external energy sources of the system, a marine secondary side waste heat removal system operation scheme based on natural circulation and forced circulation is designed, which can improve the heat removal capacity of the system and alleviate the consequences of power outages (including loss of emergency power supply) on the entire ship. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the overall structure of a marine secondary side waste heat removal system based on natural circulation and forced circulation operation in an embodiment of the present application.

[0016] Figure 2It is a structural schematic diagram of the forced circulation pipeline position of a marine secondary side waste heat removal system based on natural circulation and forced circulation operation in an embodiment of the present application.

[0017] Explanation of the reference numerals: 1. Reactor pressure vessel; 2. Steam generator; 4. Cooling assembly; 41. Cooling water tank; 42. Waste heat discharge cooler; 43. Nozzle; 44. First control valve; 45. Pressure relief valve; 5. Steam generator secondary side waste heat discharge system pipeline; 51. Medium flow pipeline; 52. First circulation valve; 53. Second circulation valve; 54. Second control valve; 6. Forced circulation assembly; 61. Forced circulation pipeline; 62. Circulation pump; 63. First control valve; 7. Power supply assembly; 71. Generator; 72. Fan blades; 73. Battery. DETAILED DESCRIPTION

[0018] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0019] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0020] The following is combined with Figure 1-2 This application is described in further detail.

[0021] The present application embodiment discloses a marine secondary side waste heat removal system based on natural circulation and forced circulation operation. Figure 1 , Figure 2 A marine secondary side waste heat removal system based on natural circulation and forced circulation operation includes a steam generator 2, a cooling component 4 is also arranged on one side of the steam generator 2, a steam generator secondary side waste heat removal system pipeline 5 is arranged between the cooling component 4 and the steam generator, the steam generator secondary side waste heat removal system pipeline 5 connects the cooling component 4 with the steam generator 2, the steam generator secondary side waste heat removal system pipeline 5 is used to exchange heat between the cooling component 4 and the steam generator 2, cool down the heat generated by the steam generator 2, and export the core waste heat and the reactor coolant and the heat storage of each equipment to the cooling water tank 41, thereby reducing the temperature and pressure inside the first circulation pipeline 3.

[0022] A forced circulation component 6 is also provided on one side of the steam generator secondary side waste heat discharge system pipeline 5. The forced circulation component 6 can accelerate the heat exchange medium inside the steam generator secondary side waste heat discharge system pipeline 5, increase the medium flow rate inside the steam generator secondary side waste heat discharge system pipeline 5, and thus improve the heat exchange efficiency of the overall system.

[0023] Reference Figure 1 , Figure 2 The cooling assembly 4 includes an outer cooling water tank 41 , and a waste heat discharge cooler 42 is arranged inside the cooling water tank 41 . The waste heat discharge cooler 42 is completely immersed in the cooling water inside the cooling water tank 41 .

[0024] The steam generator 2 is provided with a first heat exchange outlet and a first heat exchange inlet at a position relative to the waste heat discharge cooler 42 , and the side wall of the waste heat discharge cooler 42 is provided with a second heat exchange outlet and a second heat exchange inlet.

[0025] The steam generator secondary side waste heat discharge system pipeline 5 includes a medium flow pipe 51, which relatively connects the first heat exchange outlet and the second heat exchange inlet, and relatively connects the second heat exchange outlet and the first heat exchange inlet. Thus, the high-temperature steam inside the steam generator 2 enters the medium flow pipe 51 through the first heat exchange outlet, and the medium flow pipe 51 allows the high-temperature steam to enter the waste heat discharge cooler 42 through the second heat exchange inlet. The waste heat discharge cooler 42 performs heat exchange inside the cooling water tank 41, and the low-temperature liquid after the exchange enters the medium flow pipe 51 through the second heat exchange outlet, and re-enters the steam generator 2 through the first heat exchange inlet driven by the medium flow pipe 51 for circulation.

[0026] The medium flow pipe 51 is provided with a first circulation valve 52 between the first heat exchange outlet and the second heat exchange inlet, and the first circulation valve 52 is used to control the flow of the medium inside the medium flow pipe 51 between the ground heat exchange outlet and the second heat exchange inlet. The medium flow pipe 51 is provided with a second circulation valve 53 between the second heat exchange outlet and the first heat exchange inlet, and the second circulation valve 53 is used to control the flow of the medium inside the medium flow pipe 51 between the second heat exchange outlet and the first heat exchange inlet.

[0027] The forced circulation pipeline 61 includes a forced circulation pipeline 61 , both ends of which are located between the second heat exchange outlet and the first heat exchange inlet of the medium flow pipeline 51 , and the forced circulation pipeline 61 is relatively connected to the inside of the medium flow pipeline 51 .

[0028] A circulation pump 62 is fixedly connected to the forced circulation pipeline 61. The inlet end of the circulation pump 62 is located on the side close to the second heat exchange outlet, and the outlet end of the circulation pump 62 is located on the side close to the first heat exchange inlet. A first control valve 63 is provided on the side of the forced circulation pipeline 61 close to the first heat exchange inlet of the circulation pump 62. The first control valve 63 controls the flow of the medium inside the forced circulation pipeline 61.

[0029] A second control valve 54 is provided at a position of the medium flow pipeline 51 relative to the forced circulation pipeline 61 . The second control valve 54 is used to control the flow of the medium inside the medium flow pipeline 51 .

[0030] When the second control valve 54 is opened and the first control valve 63 is closed, the medium inside the medium flow pipe 51 circulates naturally inside the medium flow pipe 51, and when the pressure inside the cooling water tank 41 reaches the set value, the first control valve 63 is opened and the second control valve 54 is closed, and the medium inside the medium flow pipe 51 is forced to circulate driven by the circulation pump 62. At this time, the driving force of the medium inside the system loop is enhanced and the heat removal capacity is improved.

[0031] A power supply assembly 7 for supplying power to the circulating pump 62 is also provided on one side of the circulating pump 62. The power supply assembly 7 includes a nozzle 43 connected to the cooling water tank 41. The interior of the nozzle 43 is communicated with the cooling water tank 41. The internal opening of the nozzle 43 gradually narrows from the side close to the cooling water tank 41 to the side away from the cooling water tank 41, so that the steam flow rate at the outlet of the nozzle 43 increases through the gradual narrowing of the opening flow channel.

[0032] A spray pipe is provided on the side of the nozzle 43 away from the cooling water tank 41 , the interior of the spray pipe is relatively connected to the interior of the nozzle 43 , and a first control valve 44 is provided on the spray pipe for controlling the flow of the medium inside the spray pipe.

[0033] A generator 71 is provided at the nozzle outlet, and a fan blade 72 is provided at the input end of the generator 71. The fan blade 72 is rotated to drive the input end of the generator 71 to rotate, and the generator 71 converts the kinetic energy generated by the fan blade 72 into electrical energy for use. The blade position of the fan blade 72 is opposite to the nozzle 43, and the steam ejected from the nozzle 43 can drive the fan blade 72 to rotate quickly.

[0034] A battery 73 is also connected to one side of the generator 71 , and the battery 73 stores the electricity generated by the generator 71 . The battery 73 is relatively connected to the circulation pump 62 , and the circulation pump 62 is powered by the battery 73 .

[0035] When the ship's nuclear power system is in a power outage (including loss of emergency power), the passive residual heat removal system is put into operation. The steam generated on the secondary side of the steam generator 2 transfers heat to the cooling water in the cooling water tank 41 through the residual heat removal cooler 42, and the condensed water returns to the steam generator 2 through the steam generator secondary side residual heat removal system pipeline 5. Through the above-mentioned natural circulation process, the core residual heat and the heat storage of the reactor coolant and various equipment are discharged, and the temperature and pressure of the first circulation pipeline 3 are reduced.

[0036] When the pressure of the cooling water tank 41 reaches the set high pressure, the first control valve 44 is opened, and a large amount of steam formed by flash evaporation impacts the fan blades 72 at high speed through the nozzle 43 to rotate, and charges the battery 73 through the generator 71, thereby providing power for the circulation pump 62, and the waste heat removal system is converted into a forced circulation flow mode. At this time, the driving force of the system loop medium is enhanced, and the heat removal capacity is improved.

[0037] A pressure relief valve 45 is fixedly connected to the top of the cooling water tank 41, and the pressure relief valve 45 is connected to the interior of the cooling water tank 41. After the first control valve 44 is opened, if the pressure of the cooling water tank 41 still rises and reaches the pressure limit of the cooling water tank 41, the pressure relief valve 45 on the cooling water tank 41 automatically opens to release the pressure, and automatically closes when the pressure of the cooling water tank 41 drops to a safe pressure.

[0038] In this application, the term "plurality" means at least two or more than two, unless otherwise clearly defined. The terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0039] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

Claims

1. A marine secondary side waste heat removal system based on natural circulation and forced circulation operation, characterized in that: The invention comprises a steam generator (2), a cooling component (4) is arranged on one side of the steam generator (2), a steam generator secondary side waste heat discharge system pipeline (5) is arranged between the steam generator (2) and the cooling component (4), the steam generator secondary side waste heat discharge system pipeline (5) exchanges the temperature between the cooling component (4) and the steam generator (2), a forced circulation component (6) is arranged between the cooling component (4) and the steam generator secondary side waste heat discharge system pipeline (5), and the forced circulation component (6) enhances the circulation capacity of the steam generator secondary side waste heat discharge system pipeline (5).

2. The marine secondary side waste heat removal system based on natural circulation and forced circulation operation according to claim 1 is characterized in that: The cooling component (4) includes a cooling water tank (41), a waste heat discharge cooler (42) is arranged inside the cooling water tank (41), the waste heat discharge cooler (42) is connected to the waste heat discharge system pipeline (5) on the secondary side of the steam generator, and the waste heat discharge system pipeline (5) on the secondary side of the steam generator is connected to the forced circulation component (6).

3. The marine secondary side waste heat removal system based on natural circulation and forced circulation operation according to claim 2 is characterized in that: The steam generator secondary side waste heat discharge system pipeline (5) includes a medium flow pipeline (51), the steam generator (2) includes a first heat exchange inlet and a first heat exchange outlet, the waste heat discharge cooler (42) includes a second heat exchange inlet and a second heat exchange outlet, the medium flow pipeline (51) connects the first heat exchange outlet with the second heat exchange inlet, and the medium flow pipeline (51) connects the first heat exchange inlet with the second heat exchange outlet.

4. The marine secondary side waste heat removal system based on natural circulation and forced circulation operation according to claim 2 is characterized in that: The forced circulation component (6) includes a power supply component (7), the input end of the power supply component (7) is provided with a fan blade (72), the cooling water tank (41) is provided with a nozzle (43) at one end relative to the fan blade (72), the nozzle (43) is opposite to the blade of the fan blade (72), when the nozzle (43) is turned on, the medium inside the nozzle (43) drives the fan blade (72) to rotate, and a circulation pump (62) is provided on the pipeline (5) of the waste heat discharge system on the secondary side of the steam generator, and the power supply component (7) supplies power to the circulation pump (62).

5. The marine secondary side waste heat removal system based on natural circulation and forced circulation operation according to claim 4 is characterized in that: The steam generator secondary side waste heat removal system pipeline (5) is provided with a forced circulation pipeline (61) connected thereto, the circulation pump (62) is located on the forced circulation pipeline (61), the medium flow pipeline (51) is provided with a second control valve (54) relative to the forced circulation pipeline (61), and the forced circulation pipeline (61) is provided with a first control valve (63).

6. The marine secondary side waste heat removal system based on natural circulation and forced circulation operation according to claim 4 is characterized in that: The internal opening of the nozzle (43) gradually narrows from the side away from the fan blade (72) to the side close to the fan blade (72), and the nozzle (43) is provided with a first control valve (44) for controlling the flow of the internal medium.

7. The marine secondary side waste heat removal system based on natural circulation and forced circulation operation according to claim 4 is characterized in that: The power supply component (7) comprises a generator (71), a storage battery (73) is arranged on one side of the generator (71), the fan blades (72) rotate to drive the generator (71) to generate electricity, and the electricity generated by the generator (71) is input into the storage battery (73) for storage.

8. The marine secondary side waste heat removal system based on natural circulation and forced circulation operation according to claim 2 is characterized in that: A pressure relief valve (45) is fixedly connected to the top end of the cooling water tank (41).

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