Stirling engine-based nuclear power reactor cavity passive circulation cooling system
By using a non-active cyclic cooling system driven by a Stirling engine in a nuclear power plant, the problem of coolant system failure in serious accidents in nuclear power plant is solved, and the continuous cooling of the reactor pressure vessel is achieved, ensuring the safety of the reactor.
Patent Information
- Application Number
- CN201910954757.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2019-10-09
- Publication Date
- 2024-12-17
- Estimated Expiration
- 2039-10-09
AI Technical Summary
In the event of a serious accident in a nuclear power plant, circulating cooling cannot be achieved when the reactor coolant system fails, resulting in overheating of the outer wall of the reactor pressure vessel, threatening the integrity and safety of the reactor.
Using a non-active circulating cooling system for the nuclear power reactor chamber based on Stirling engine, the heat in the chamber is transmitted to the Stirling engine through the heat transfer device, and the coolant transfer device is driven to inject cooling water into circulating mode to ensure the reactor pressure vessel. cooling.
In the absence of external power, continuous cooling of the reactor pressure vessel is achieved to ensure its integrity and safety and prevent burning or melting.
Smart Images
Figure CN110648771B_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of nuclear power plant design, and in particular relates to a nuclear power reactor cavity passive circulation cooling system based on a Stirling engine. Background Art
[0002] A nuclear power plant is a facility that converts nuclear energy into electrical energy through appropriate devices. A nuclear power plant uses a nuclear reactor to replace the boiler of a thermal power plant. Nuclear fuel undergoes a special form of "combustion" in the nuclear reactor to generate heat, which converts nuclear energy into thermal energy to heat water and produce steam. The systems and equipment of a nuclear power plant usually consist of two major parts: nuclear systems and equipment, also known as the nuclear island; and conventional systems and equipment, also known as the conventional island.
[0003] During the operation of a nuclear power plant, when the nuclear power plant encounters a serious accident and the entire station loses power, the reactor will automatically shut down, but at the same time, the emergency cooling system, that is, the residual heat removal system, must be started. This system is to play an emergency cooling role in the core when the normal cooling system cannot cool the core in the event of an accident such as the main pump stopping, that is, a loss of flow accident, and a primary circuit pipeline damage, that is, a loss of water accident, to prevent the core from overheating and melting. Currently, active and passive technologies are mainly used to solve this problem. Active technologies rely on external forces such as emergency power supplies or diesel engines to drive pumps to inject cooling water into the core. Passive technologies rely on natural circulation, gravity, compressed nitrogen and other natural forces to inject cooling water into the core and achieve long-term cooling cycles. The key to these technologies is how to provide power for the emergency cooling system and ensure its reliability, stability and sustainability, thereby ensuring the safety of the nuclear power plant.
[0004] 1. The first barrier to ensure the safety of nuclear power plants is to ensure that the nuclear fuel in the nuclear reactor pressure vessel will not be damaged or melted. Under normal operating conditions and design basis accident conditions, the reactor coolant system ensures that the nuclear fuel is always immersed in coolant and does not burn or melt due to exposure.
[0005] 2. However, in the event of a serious accident, the reactor coolant system may fail to function, exposing the nuclear fuel in the reactor pressure vessel, causing the reactor core to burn dry and the nuclear fuel to burn or melt. At this time, it is necessary to try to ensure the integrity of the second barrier - the reactor pressure vessel. The burned or melted nuclear fuel quickly heats the outer wall of the reactor pressure vessel. If the outer wall of the reactor pressure vessel is not cooled, it will be difficult to ensure the integrity of the reactor pressure vessel.
[0006] 3. By setting up a reactor cavity injection water system, it can be ensured that cooling water is injected into the cavity to cool the outer wall of the reactor pressure vessel when the temperature of the reactor pressure vessel shell increases significantly. However, the current system generally adopts an active method, such as using an external power source to drive the water injection pump to circulate water, or using a pressurized storage tank to inject cooling water into the cavity in a passive manner at one time, but it is impossible to perform circulating cooling. It is expected to study a passive circulating cooling system for the nuclear power reactor cavity based on a Stirling engine to ensure that in the event of a serious accident, especially when the nuclear power plant loses all external power supplies, the system can inject cooling water into the reactor cavity in a circulating manner, continuously remove the heat radiated from the reactor pressure vessel to the cavity, and ensure the integrity and safety of the reactor pressure vessel. Summary of the invention
[0007] In view of the above problems, the present invention provides a nuclear power reactor cavity passive circulation cooling system based on Stirling engine.
[0008] The cooling system comprises: a reactor cavity device, a heat transfer device, a coolant storage device, a Stirling engine and a coolant transmission device;
[0009] One end of the heat transfer device is connected to the interior of the stack cavity device, and the other end of the heat transfer device is connected to the input end of the Stirling engine;
[0010] The output end of the Stirling engine is drivingly connected to the power input end of the coolant transmission device;
[0011] The stack cavity device forms a circulation loop with the coolant storage device through the coolant transmission device.
[0012] Furthermore, the stack cavity device includes a stack cavity body.
[0013] Further, the heat transfer device includes one or more groups of heat transfer rods;
[0014] One end of the heat transfer rod is communicated with the reactor cavity body, and the other end of the heat transfer rod is communicated with the heat storage chamber of the Stirling engine, so as to transfer the heat in the reactor cavity body to the heat storage chamber.
[0015] Further, the coolant transmission device includes a water pump, a suction pipeline, an injection pipeline and a drainage pipeline;
[0016] The power input end of the water pump is drivingly connected to the output end of the Stirling engine;
[0017] One end of the suction pipeline is connected to the water inlet of the water pump, and the other end of the suction pipeline is connected to the coolant storage device;
[0018] One end of the injection pipeline is connected to the water outlet of the water pump, and the other end of the injection pipeline extends into the reactor cavity body;
[0019] One end of the drainage pipeline is in communication with the side wall of the reactor cavity body, and the other end of the drainage pipeline is in communication with the coolant storage device.
[0020] Furthermore, the coolant storage device is a pit water injection tank, in which coolant is arranged, and the device is arranged outside the reactor building.
[0021] Furthermore, the highest water level of the coolant in the coolant storage device is lower than the core cavity drainage hole in the core cavity body.
[0022] Furthermore, the coolant storage device is a sealed pressure container.
[0023] Furthermore, the number of the Stirling engine is at least one, and the number of heat transfer rods connected to each Stirling engine is the same.
[0024] Further, the cooling system also includes a generator;
[0025] The input end of the generator is drivingly connected to the output end of the Stirling engine.
[0026] The Stirling engine-based nuclear power reactor cavity passive circulation cooling system proposed by the present invention can ensure that when a nuclear power plant encounters a serious accident, especially when the nuclear power plant loses all external power supplies, the system can passively inject cooling water into the nuclear reactor cavity in a circulating manner, continuously remove the heat radiated from the nuclear reactor pressure vessel into the nuclear reactor cavity, and ensure the integrity and safety of the nuclear reactor pressure vessel. Other features and advantages of the present invention will be explained in the subsequent description, and partly become obvious from the description, or can be understood by practicing the present invention. The objects and other advantages of the present invention can be achieved and obtained through the structures indicated in the description, claims and drawings. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0028] Figure 1 The schematic diagram of the structure of the passive circulation cooling system of the nuclear power reactor cavity based on the Stirling engine of the present invention is shown;
[0029] Figure 2 The diagram shows the connection structure of the passive reactor cavity circulation cooling system, the generator and the storage battery of the present invention.
[0030] In the figure: 1-core cavity device, 101-core cavity body, 1011-core cavity drainage hole, 2-heat transfer device, 201-heat transfer rod, 3-coolant storage device, 4-Stirling engine, 401-heat storage chamber, 402-first cylinder-piston, 403-second cylinder-piston, 404-transmission mechanism, 5-coolant transmission device, 501-water pump, 502-intake pipeline, 503-injection pipeline, 504-drainage pipeline, 6-reactor pressure vessel, 7-reactor fuel assembly, 8-generator, 9-battery. DETAILED DESCRIPTION
[0031] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0032] In order to simplify the drawings, only the parts related to the present invention are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked. In this article, "one" not only means "only one", but also means "more than one".
[0033] The present invention discloses a nuclear power reactor cavity passive circulation cooling system based on a Stirling engine, which can ensure that in the event of a serious accident, especially when a nuclear power plant loses all external power supplies, the system can inject cooling water into the reactor cavity of the nuclear reactor in a circulation manner under the premise of being passive, continuously remove the heat radiated from the nuclear reactor pressure vessel to the reactor cavity of the nuclear reactor, and ensure the integrity and safety of the nuclear reactor pressure vessel.
[0034] like Figure 1 As shown, the Stirling engine-based nuclear power reactor cavity passive circulation cooling system of the present invention comprises a cavity device 1, a heat transfer device 2, a storage device 3, a Stirling engine 4 and a coolant transmission device 5;
[0035] The reactor cavity device 1 includes a reactor cavity body 101. The container for placing the reactor fuel assembly 7 in the nuclear power plant, namely the reactor pressure vessel 6, is placed in the reactor cavity body 101. The reactor fuel assembly 7 performs a nuclear reaction inside the reactor pressure vessel 6. There is no coolant in the reactor cavity body 101 during normal operation. In the event of a serious accident, coolant is injected through the water injection pipeline.
[0036] In order to ensure that the cooling water level does not overflow the reactor cavity body 101 and is always located inside the reactor cavity body 101 when the reactor cavity is filled with water, a reactor cavity drainage hole 1011 is provided on the side wall of the reactor cavity body 101, and the reactor cavity drainage holes 1011 are vertically distributed on the side wall of the reactor cavity body 101, and the reactor cavity drainage holes 1011 are arranged above the reactor cavity. The reactor cavity drainage holes 1011 are connected to the drainage pipeline 504. When the reactor cavity water level reaches the water level of the reactor cavity drainage holes 1011, the coolant flows back to the coolant storage device 3 through the reactor cavity drainage holes 1011 and the drainage pipeline 504.
[0037] The heat transfer device 2 radiates the heat in the reactor cavity device 1 to the Stirling engine 4; the heat transfer device 2 includes a plurality of heat transfer rods 201, one end of each of the heat transfer rods 201 is directly in contact with the coolant, and the other end of each of the heat transfer rods 201 passes through the bottom wall or side wall of the reactor cavity body 101 to reach the outside and is connected to the Stirling engine 4, and radiates heat to the Stirling engine 4.
[0038] The coolant storage device 3 is a pit water injection tank, which is located outside the nuclear power plant reaction building, and the highest water level of the pit water injection tank is lower than the reactor cavity drainage hole 1011 of the reactor cavity body 101, so as to ensure the stable circulation of cooling water.
[0039] The Stirling engine 4 is connected to the stack cavity device 1 via the heat transfer device 2 .
[0040] Specifically, the Stirling engine 4 includes a heat storage chamber 401, a first cylinder-piston 402, a second cylinder-piston 403 and a transmission mechanism 404. The heat storage chamber 401 is connected to the first cylinder-piston 402 and the second cylinder-piston 403 respectively. The cylinder in the first cylinder-piston 402 is a hot cylinder, and the cylinder in the second cylinder-piston 403 is a cold cylinder. When the heat transfer rods 201 transfer heat to the hot cylinder, the piston inside it is pushed to move outward, and the piston of the cold cylinder is driven to move inward. When the hot cylinder piston moves outward to a certain position, the hot air inside the hot cylinder is quickly transferred to the cold cylinder through the built-in heat exchange channel, and then the cold cylinder piston is pushed to move outward and the hot cylinder piston is driven to move inward, and the heat is dissipated from the cold cylinder. Through the reciprocating movement of the first cylinder-piston 402 and the second cylinder-piston 403, the transmission mechanism 404 is driven to move, and the Stirling engine 4 generates kinetic energy as a whole.
[0041] Furthermore, the number of the Stirling engine 4 is at least one. When the number of the Stirling engines 4 is greater than or equal to 2, the number of the heat transfer rods 201 connected to each Stirling engine 4 is the same.
[0042] The coolant transmission device 5 includes a water pump 501, a suction pipeline 502, an injection pipeline 503 and a drainage pipeline 504;
[0043] The power input end of the water pump 501 is drivingly connected to the output end of the Stirling engine 4;
[0044] One end of the suction line 502 is connected to the input end of the water pump 501, and the other end of the suction line 502 is connected to the coolant storage device 3;
[0045] One end of the injection pipeline 503 is connected to the output end of the water pump 501, and the other end of the injection pipeline 503 extends into the reactor cavity body 101;
[0046] One end of the drainage pipeline 504 is connected to the reactor cavity drainage hole 1011 , and the other end of the drainage pipeline 504 is connected to the coolant storage device 3 .
[0047] Specifically, the reactor cavity drainage hole 1011 is connected to one end of the drainage pipeline 504, and the other end of the drainage pipeline 504 is connected to the pit water injection tank arranged outside the nuclear reactor building. When the reactor cavity body 101 is continuously injected with cooling water with a relatively low temperature, when the water level reaches the drainage pipeline 504, the cooling water will be transported back to the pit water injection tank by overflowing from the drainage pipeline 504.
[0048] Exemplarily, during the nuclear reaction, the reactor fuel assembly 7 reacts inside the reactor pressure vessel 6. In the event of a serious accident, such as when the nuclear power plant suffers a power outage, the reactor fuel assembly 7 will generate huge decay heat due to the lack of coolant cooling, and the huge heat is quickly transferred to the reactor cavity body 101 through the side wall of the reactor pressure vessel 6. At this time, multiple heat transfer rods 201 will radiate the heat absorbed from the reactor cavity body 101 to the heat storage chamber 401 of the Stirling engine 4. After the heat storage chamber 401 continuously collects the heat transferred by the heat transfer rods 201, the Stirling engine 4 starts to work, thereby driving the water pump 501 connected thereto. The input end of the water pump 501 is connected to the pit water injection tank outside the nuclear reactor building through the suction pipeline 502. The inside of the pit water injection tank cools the circulating cooling water by natural cooling. The output end of the water pump 501 is connected to one end of the injection pipeline 503. The other end of the injection pipeline 503 is connected to the reactor cavity body 101. After the water pump 501 is driven by the transmission mechanism 404 of the Stirling engine 4 to start working, the water in the pit water injection tank is transported to the reactor cavity body 101 through the suction pipeline 502 and the injection pipeline 503 in turn. When the water level reaches the bottom of the reactor pressure vessel 6, the outer wall of the reactor pressure vessel 6 will be cooled down.
[0049] Furthermore, the heat transfer rods 201 referred to in the present invention are made of diamond, copper or silicon, and the heat transfer rods 201 are evenly dispersed in the reactor cavity body 101 .
[0050] Exemplarily, the heat transfer rod 201 is made of copper material, and multiple heat transfer rods 201 are distributed in the reactor cavity body 101 in concentric circles. The multiple heat transfer rods 201 simultaneously absorb the heat in the reactor cavity body 101 and transfer it to the heat storage chamber 401, so as to achieve the purpose of quickly dissipating the large amount of decay heat generated by the reactor fuel assembly 7 in the event of a serious accident. At the same time, this heat is used as the energy to drive the Stirling engine 4, and then drive the water pump 501 to pump the cooling water in the pit water injection tank into the reactor cavity body 101, so as to cool the reactor pressure vessel 6 to ensure the integrity of the reactor pressure vessel 6 of the nuclear power plant.
[0051] Furthermore, Figure 2As shown, the Stirling engine 4 is also connected to a generator 8. When the heat storage chamber 401 uses the heat received from the heat transfer rod 201 as energy to drive the Stirling engine 4, the Stirling engine 4 starts working and then drives the generator 8 connected thereto. The generator 8 can be connected to a battery 9. The battery 9 is used to store electrical energy. The stored electrical energy is used to provide a monitoring system and / or a lighting system and / or local ventilation for the nuclear reactor in the event of a serious accident. The electrical energy generated by the generator 8 can also be directly used to provide an emergency backup working power supply for the monitoring system and / or the lighting system and / or local ventilation for the nuclear reactor in the event of a serious accident, thereby further maintaining the safe operation of the system.
[0052] Furthermore, the number of Stirling engines 4 in the system is at least one. Exemplarily, the number of Stirling engines 4 is four, and the number of heat transfer rods 201 connected to each Stirling engine 4 is the same. Each Stirling engine 4 is connected to a generator 8, but the four generators 8 are respectively connected to a battery 9, a monitoring system of the nuclear reaction system, a lighting system of the nuclear reaction system, and a local ventilation system of the nuclear reaction system. When one of the Stirling engines encounters a special situation, the other Stirling engines 4 and the battery 9 can serve as an emergency backup power supply to ensure the normal operation of the system.
[0053] When the nuclear power plant returns to normal and the heat generated by the entire system and the cooling rate are maintained at a balanced level, the heat dissipation effect of the system returns to normal, and the heat of the reactor cavity body 101 eventually decreases. When the heat conducted to the heat storage chamber 401 through the heat transfer rod 201 is difficult to drive the Stirling engine 4 to provide kinetic energy, the circulating water cooling system automatically stops.
[0054] Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent substitutions for some of the technical features therein; and these modifications or substitutions do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A passive circulation cooling system for the nuclear power reactor cavity based on a Stirling engine. Features: The cooling system comprises: a reactor cavity device (1), a heat transfer device (2), a coolant storage device (3), a Stirling engine (4) and a coolant transmission device (5); One end of the heat transfer device (2) is connected to the interior of the reactor cavity device (1), and the other end of the heat transfer device (2) is connected to the input end of the Stirling engine (4); The stack cavity device (1) comprises a stack cavity body (101); The heat transfer device (2) comprises one or more groups of heat transfer rods (201); The Stirling engine (4) comprises a heat storage chamber (401), a first cylinder-piston (402), a second cylinder-piston (403) and a transmission mechanism (404); the heat storage chamber (401) is respectively connected to the first cylinder-piston (402) and the second cylinder-piston (403); the cylinder in the first cylinder-piston (402) is a hot cylinder, and the cylinder in the second cylinder-piston (403) is a cold cylinder. When the plurality of heat transfer rods (201) transfer heat to the When the hot cylinder is in motion, the piston inside it is pushed to move outward, and at the same time, the piston of the cold cylinder is driven to move inward. When the hot cylinder piston moves outward to a certain position, the hot air inside the hot cylinder is quickly transferred to the cold cylinder through the built-in heat exchange channel, and then the cold cylinder piston is pushed to move outward and the hot cylinder piston is driven to move inward. At the same time, the heat is dissipated from the cold cylinder, and the transmission mechanism (404) is driven to move through the reciprocating movement of the first cylinder-piston (402) and the second cylinder-piston (403); One end of the heat transfer rod (201) is in communication with the reactor cavity body (101), and the other end of the heat transfer rod (201) is in communication with the heat storage chamber (401) of the Stirling engine (4), so as to transfer the heat in the reactor cavity body (101) to the heat storage chamber (401); The output end of the Stirling engine (4) is drivingly connected to the power input end of the coolant transmission device (5); The stack cavity device (1) forms a circulation loop with the coolant storage device (3) through the coolant transmission device (5).
2. The Stirling engine-based nuclear power reactor cavity passive circulation cooling system according to claim 1, Features: The cooling liquid transmission device (5) comprises a water pump (501), a suction pipeline (502), an injection pipeline (503) and a drainage pipeline (504); The power input end of the water pump (501) is drivingly connected to the output end of the Stirling engine (4); One end of the suction pipeline (502) is connected to the water inlet of the water pump (501), and the other end of the suction pipeline (502) is connected to the coolant storage device (3); One end of the injection pipeline (503) is connected to the water outlet of the water pump (501), and the other end of the injection pipeline (503) extends into the reactor cavity body (101); One end of the drainage pipeline (504) is in communication with the side wall of the reactor cavity body (101), and the other end of the drainage pipeline (504) is in communication with the coolant storage device (3).
3. The Stirling engine-based nuclear power reactor cavity passive circulation cooling system according to claim 1, Features: The coolant storage device (3) is a pit water injection tank, in which coolant is arranged. The device is arranged outside the reactor building.
4. The Stirling engine-based nuclear power reactor cavity passive circulation cooling system according to claim 1, Features: The highest water level of the coolant in the coolant storage device (3) is lower than the reactor cavity drainage hole (1011) in the reactor cavity body (101).
5. The Stirling engine-based nuclear power reactor cavity passive circulation cooling system according to claim 1, Features: The cooling liquid storage device (3) is a sealed pressure container.
6. The Stirling engine-based nuclear power reactor cavity passive circulation cooling system according to claim 1, Features: The number of the Stirling engine (4) is at least one, and the number of heat transfer rods (201) connected to each Stirling engine (4) is the same.
7. A Stirling engine-based nuclear power reactor cavity passive circulation cooling system according to any one of claims 1 to 6, Features: The cooling system also includes a generator (8); The input end of the generator (8) is drivingly connected to the output end of the Stirling engine (4).