阅读说明：本技术 基于安全壳和反应堆容器的铅基快堆非能动余热排出系统 (Lead-based fast reactor passive residual heat removal system based on containment and reactor vessel ) 是由 蔡容 彭诗念 余红星 严明宇 黄代顺 邓坚 郭超 方红宇 冉旭 鲜麟 李峰 杨 于 2021-06-23 设计创作，主要内容包括：本发明公开了基于安全壳和反应堆容器的铅基快堆非能动余热排出系统,涉及核反应堆技术领域,其技术方案要点是：堆坑的腔室内设有隔离围板,隔离围板与堆坑内壁之间形成外腔室,隔离围板与反应堆容器外壁之间形成内腔室,隔离围板穿设有将外腔室、内腔室连通的连通孔；冷却水箱的输出端口与外腔室的输入端口之间通过配置有隔离阀的管道连通设置,内腔室的输出端口与安全壳的内部空间连通；安全壳内壁设有至少一个收集器,收集器的输出端口与冷却水箱的输入端口之间通过管道连通。本发明提供的余热排出系统采用非能动技术,在反应堆的正常排热途径失效时,不依赖外部动力电源导出堆芯余热,从而确保反应堆的安全。(The invention discloses a lead-based fast reactor passive residual heat removal system based on a containment and a reactor vessel, which relates to the technical field of nuclear reactors and adopts the technical scheme that: an isolation coaming is arranged in the cavity of the reactor pit, an outer cavity is formed between the isolation coaming and the inner wall of the reactor pit, an inner cavity is formed between the isolation coaming and the outer wall of the reactor vessel, and a communicating hole for communicating the outer cavity and the inner cavity is arranged in the isolation coaming in a penetrating way; the output port of the cooling water tank is communicated with the input port of the outer chamber through a pipeline provided with an isolation valve, and the output port of the inner chamber is communicated with the inner space of the containment vessel; the inner wall of the containment is provided with at least one collector, and the output port of the collector is communicated with the input port of the cooling water tank through a pipeline. The waste heat discharge system provided by the invention adopts a passive technology, and does not rely on an external power supply to lead out the waste heat of the reactor core when the normal heat discharge path of the reactor fails, thereby ensuring the safety of the reactor.)

1. The lead-based fast reactor passive residual heat removal system based on the containment and the reactor vessel comprises the containment (101), a cooling water tank (103) and the reactor vessel (106), wherein a reactor pit (102) for installing the reactor vessel (106) is arranged at the bottom of the reactor vessel (106), and the lead-based fast reactor passive residual heat removal system is characterized in that an isolation coaming plate (107) is arranged in a cavity of the reactor pit (102), an outer cavity (109) is formed between the isolation coaming plate (107) and the inner wall of the reactor pit (102), an inner cavity (110) is formed between the isolation coaming plate (107) and the outer wall of the reactor vessel (106), and a communicating hole (108) for communicating the outer cavity (109) and the inner cavity (110) is formed in the isolation coaming plate (107) in a penetrating manner;

an output port of the cooling water tank (103) is communicated with an input port of the outer chamber (109) through a pipeline provided with an isolation valve (104), and an output port of the inner chamber (110) is communicated with the inner space of the containment vessel (101);

at least one collector (105) is arranged on the inner wall of the containment (101), and an output port of the collector (105) is communicated with an input port of the cooling water tank (103) through a pipeline.

2. The passive residual heat removal system of the lead-based fast reactor based on the containment and the reactor vessel as claimed in claim 1, wherein the isolation valve (104) is in a closed state when the reactor vessel (106) is in normal operation; the isolation valve (104) is in an open state when the reactor vessel (106) is in an accident condition.

3. The passive residual heat removal system of the lead-based fast reactor based on the containment and the reactor vessel as recited in claim 2, wherein the isolation valve (104) is opened in response to a UPS anomaly signal, and the UPS anomaly signal is triggered when the reactor vessel (106) is detected to be in power supply anomaly.

4. The passive residual heat removal system of the lead-based fast reactor based on the containment and the reactor vessel is characterized in that an input port of the outer chamber (109) and an output port of the inner chamber (110) are both positioned at the top of the chamber of the reactor pit (102), and the communication hole (108) is positioned at the bottom of the isolation surrounding plate (107).

5. The passive residual heat removal system of the lead-based fast reactor based on the containment and the reactor vessel as claimed in claim 1, wherein the isolation surrounding plate (107) is a cylindrical structure coaxially arranged with the reactor vessel (106), and the communication hole (108) is any one of a circular hole, a polygonal hole, a quincunx hole and a pentagonal hole.

6. The passive residual heat removal system of the lead-based fast reactor based on the containment and the reactor vessel is characterized in that the height of an output port of the cooling water tank (103) is larger than that of an input port of the outer chamber (109).

7. The passive lead-based fast reactor residual heat removal system based on the containment and the reactor vessel as claimed in any one of claims 1 to 5, wherein the height of the input port of the outer chamber (109) and the height of the output port of the inner chamber (110) are both greater than the liquid level of the lead pool.

8. The passive residual heat removal system of the lead-based fast reactor based on the containment and the reactor vessel is characterized in that the height of an output port of the collector (105) is larger than that of an input port of the cooling water tank (103).

9. The passive lead-based fast reactor residual heat removal system based on the containment and the reactor vessel is characterized in that the collector (105) is of an annular structure, and the outer wall of the collector (105) is attached to the inner wall of the containment (101).

10. The passive residual heat removal system of the lead-based fast reactor based on the containment and the reactor vessel is characterized in that the cooling water tank (103) and the isolation valve (104) are arranged in the containment (101).

Technical Field

The invention relates to the technical field of nuclear reactors, in particular to a lead-based fast reactor passive waste heat removal system based on a containment and a reactor vessel.

Background

The lead-based fast reactor is a fourth-generation nuclear energy system with great development potential, adopts lead-based materials (lead or lead-bismuth alloy) as a coolant, has good neutron physical characteristics, thermal hydraulic characteristics, chemical safety characteristics and system safety characteristics, has unique advantages in the aspects of nuclear fuel proliferation and nuclear waste transmutation, and is a hotspot of current international nuclear energy field research. The waste heat discharge system is one of the specially designed safety systems of the reactor, and has the main function of discharging the waste heat of the reactor core under the accident condition of the reactor, so that the safety of the reactor core is ensured. The passive residual heat removal system simplifies the system of the reactor, improves the reliability of the system operation, reduces the probability of reactor core melting, and improves the safety and the economy of the reactor. The design and research of the passive residual heat removal system are one of the important development directions of the research of the lead-based fast reactor. At present, a passive residual heat removal system of a lead-based fast reactor is still in a conceptual design stage, and countries developing the lead-based fast reactor technology internationally perform design research on the passive residual heat removal system of the lead-based fast reactor.

The waste heat removal system of the American SSTAR reactor is a reactor container auxiliary cooling system (RVACS) and utilizes the natural circulation heat exchange between the outer wall surface of the container and air to take away heat. The European lead-based fast reactor ELSY-600 is designed with three passive residual heat removal systems: a water waste heat discharge system, an independent condenser waste heat discharge system and a reactor container air cooling system. The independent condenser waste heat discharge system comprises a steam generator secondary side, a condenser, a water tank and the like, and the reactor core waste heat is taken away through heat exchange of the steam generator and then is led into the water tank by the condenser. The water waste heat discharge system comprises a water tank, an isolation valve, a soaking type heat exchanger and a chimney, heat is led out by the soaking type heat exchanger, and water vapor flows into the atmospheric environment through the chimney. The reactor vessel air cooling system is different from the American SSTAR reactor vessel auxiliary cooling system, the system adopts a pipeline cooling design scheme, the inlet of the system is connected with an air collector, and the outlet of the system is connected with a chimney, so that natural circulation is formed, and the SSTAR reactor directly utilizes a tunnel.

The passive residual heat removal system of the small modular lead-cooled fast reactor SVBR-100 developed in Russia only consists of a steel tank which also serves as a protective container, and the tank is filled with water. The heat is led out from the wall of the reactor vessel, and the passive residual heat removal system can ensure that the heat in the reactor vessel is led out under various conditions. The Russian exemplary verification shows that a decay heat removal system of a reactor core BREST-OD-300 adopts a passive design, heat of a primary loop is transferred to cold air in an air cooler through natural circulation, and the heated air is directly discharged into the atmosphere.

In summary, the passive residual heat removal system based on the steam generator and the independent heat exchanger has larger power, but more equipment needs to be configured, the size of the equipment is not small, the space of a lead pool in a reactor container is limited, and the installation, the fixation and the maintenance of the equipment are difficult. In the design of a passive residual heat removal system based on a reactor container, the design of an air cooling reactor container is selected in the United states, European Union and the like, the design of the type causes the reactor to have certain heat loss under normal working conditions, and the biggest problem is that the heat removal power of the passive residual heat removal system is small; russian selects the design of water cooling reactor container, the natural convection through radiant heat transfer and container wall takes away the reactor core waste heat, but this type design is at present with the reactor container soaking in the water tank, this kind of design leads to the reactor normal operating mode to have certain heat loss, the reactor container does not form the natural circulation outward and flows, whole waste heat discharge system's heat extraction power is on the small side, this waste heat discharge system operation a period back water tank water can all evaporate in addition, lead to its heat extraction power precipitous drop.

Disclosure of Invention

In order to solve the defects in the prior art, the invention aims to provide a lead-based fast reactor passive residual heat removal system based on a containment vessel and a reactor vessel, which operates in a natural circulation mode under accident conditions and conducts reactor core residual heat to the final hot-trap atmosphere.

The technical purpose of the invention is realized by the following technical scheme: the lead-based fast reactor passive residual heat removal system based on the containment and the reactor vessel comprises the containment, a cooling water tank and the reactor vessel, wherein a reactor pit for installing the reactor vessel is arranged at the bottom of the reactor vessel, an isolation coaming is arranged in a cavity of the reactor pit, an outer cavity is formed between the isolation coaming and the inner wall of the reactor pit, an inner cavity is formed between the isolation coaming and the outer wall of the reactor vessel, and a communication hole for communicating the outer cavity and the inner cavity is formed in the isolation coaming in a penetrating manner;

the output port of the cooling water tank is communicated with the input port of the outer chamber through a pipeline provided with an isolation valve, and the output port of the inner chamber is communicated with the inner space of the containment vessel;

the inner wall of the containment is provided with at least one collector, and the output port of the collector is communicated with the input port of the cooling water tank through a pipeline.

Further, when the reactor vessel normally operates, the isolation valve is in a closed state; when the reactor vessel is in an accident condition, the isolation valve is in an open state.

Further, the isolation valve is started to be opened after responding to the UPS abnormal signal, and the UPS abnormal signal is triggered when the reactor container is detected to be in power supply abnormality.

Furthermore, the input port of the outer chamber and the output port of the inner chamber are both positioned at the top of the chamber of the pile pit, and the communication hole is positioned at the bottom of the isolation coaming.

Furthermore, the isolation surrounding plate is of a cylindrical structure which is coaxial with the reactor vessel, and the communication hole is any one of a circular hole, a polygonal hole, a quincuncial hole and a pentagonal hole.

Further, the height of the output port of the cooling water tank is larger than that of the input port of the outer chamber.

Furthermore, the height of the input port of the outer chamber and the height of the output port of the inner chamber are both greater than the height of the liquid level of the lead pool.

Further, the height of the output port of the collector is larger than that of the input port of the cooling water tank.

Furthermore, the collector is of an annular structure, and the outer wall of the collector is attached to the inner wall of the containment.

Furthermore, the cooling water tank and the isolation valve are both arranged in the containment.

Compared with the prior art, the invention has the following beneficial effects:

1. the waste heat discharge system provided by the invention adopts a passive technology, and does not rely on an external power supply to lead out the waste heat of the reactor core when the normal heat discharge path of the reactor fails, thereby ensuring the safety of the reactor.

2. The waste heat discharge system provided by the invention adopts a closed cycle design, and selects an atmospheric environment as a final heat sink, so that the waste heat discharge system can run for a long time and continuously lead out the waste heat of a reactor core.

3. The waste heat discharge system provided by the invention fully utilizes the containment vessel and the reactor vessel, requires less matched equipment and corresponding auxiliary systems, and has the advantages of simple equipment and simple installation and maintenance.

4. The residual heat removal system provided by the invention does not increase penetration pieces of the reactor vessel and the containment vessel, namely, does not damage the second and third safety barriers of the reactor, so that the risk of radioactive substances to be released outside is not increased.

5. The waste heat discharge system provided by the invention has the advantages that under the normal operation condition of the reactor, the water tank isolation valve is in a closed state, the pile pit cavity is filled with stagnant air, and the heat loss caused by the waste heat discharge system is little.

6. The waste heat discharge system provided by the invention divides the pit cavity into two parts by arranging the heat insulation enclosing plate, and a natural circulation flow passage is established by the design, so that macroscopic natural circulation flow can be formed in the pit, and the waste heat discharge system has stronger heat discharge capacity.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principles of the invention. In the drawings:

fig. 1 is a schematic diagram of the working principle in the embodiment of the present invention.

Reference numbers and corresponding part names in the drawings:

101. a containment vessel; 102. piling a pit; 103. a cooling water tank; 104. an isolation valve; 105. a collector; 106. a reactor vessel; 107. isolating the coaming; 108. a communicating hole; 109. an outer chamber; 110. an inner chamber.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail below with reference to examples and accompanying drawings, and the exemplary embodiments and descriptions thereof are only used for explaining the present invention and are not meant to limit the present invention.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly or indirectly connected to the other element.

It will be understood that the terms "length," "width," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like, as used herein, refer to an orientation or positional relationship indicated in the drawings that is solely for the purpose of facilitating the description and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and is therefore not to be construed as limiting the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise.

Example (b): the lead-based fast reactor passive residual heat removal system based on the containment and the reactor vessel, as shown in fig. 1, includes a containment 101, a cooling water tank 103, and a reactor vessel 106, and a pit 102 for installing the reactor vessel 106 is provided at the bottom of the reactor vessel 106. An isolation surrounding plate 107 is arranged in the cavity of the stack pit 102, an outer cavity 109 is formed between the isolation surrounding plate 107 and the inner wall of the stack pit 102, an inner cavity 110 is formed between the isolation surrounding plate 107 and the outer wall of the reactor vessel 106, and a communication hole 108 for communicating the outer cavity 109 and the inner cavity 110 is arranged in the isolation surrounding plate 107 in a penetrating mode. An output port of the cooling water tank 103 is communicated with an input port of the outer chamber 109 through a pipeline provided with an isolation valve 104, and an output port of the inner chamber 110 is communicated with the inner space of the containment vessel 101; the inner wall of the containment vessel 101 is provided with a collector 105, and an output port of the collector 105 is communicated with an input port of the cooling water tank 103 through a pipeline.

It should be noted that the instruments, pipes, and lines described in this embodiment are all disposed in the containment vessel 101. The residual heat removal system does not increase penetration pieces of the reactor vessel 106 and the containment vessel 101, namely, does not damage the second and third safety barriers of the reactor, so that the risk of radioactive substances releasing outside is not increased.

When the reactor vessel 106 is operating normally, the isolation valve 104 is in a closed state; when the reactor vessel 106 is in an accident condition, the isolation valve 104 is in an open state. Wherein the isolation valve 104 is activated to open in response to a UPS anomaly signal, which is triggered when the reactor vessel 106 is detected to be in a power supply anomaly.

In this embodiment, the input port of the outer chamber 109 and the output port of the inner chamber 110 are both located at the top of the chamber of the stack pit 102, and the communication hole 108 is located at the bottom of the isolation fence 107.

In the present embodiment, the partition wall 107 has a cylindrical structure provided coaxially with the reactor vessel 106, and the communication hole 108 is any one of a circular hole, a polygonal hole, a quincunx hole, and a pentagonal hole. In the present embodiment, the communication hole 108 is a circular hole.

The height of the outlet port of the cooling water tank 103 is greater than the height of the inlet port of the outer chamber 109, which ensures that the water in the cooling water tank 103 can flow into the cavity of the pit 102. In addition, the height of the input port of the outer chamber 109 and the height of the output port of the inner chamber 110 are both greater than the height of the liquid level of the lead pool, so that the normal operation of heat exchange of the reactor vessel 106 is effectively ensured. In addition, the height of the output port of the collector 105 is greater than the height of the input port of the cooling water tank 103, ensuring that water can flow into the cooling water tank 103.

In the embodiment, the collector 105 has a ring structure, and an outer wall of the collector 105 is attached to an inner wall of the containment vessel 101.

The working process is as follows: under the normal working condition of the reactor, the isolation valve 104 corresponding to the cooling water tank 103 is in a closed state, and the inner cavity of the reactor pit 102 is filled with stagnant air. Under the accident condition of the reactor, particularly under the power-off condition (reliable power loss) of the whole plant, the isolation valve 104 corresponding to the cooling water tank 103 is automatically opened, the water in the cooling water tank 103 flows into the outer chamber 109 of the pit 102 under gravity, then enters the inner chamber 110 through the communication hole 108, the water in the inner chamber 110 contacts with the outer wall of the reactor vessel 106, the water is heated to be steam under the action of the convection heat exchange and the radiation heat exchange of the wall of the reactor vessel 106, the steam flows upwards under the driving action of the density difference and flows out of the chamber of the pit 102, thereby flowing into the large space of the containment vessel 101, in the large space of the containment vessel 101, the water vapor continues to flow upwards, the water vapor is condensed at the dome of the containment vessel 101 and the wall of the containment vessel 101, and the condensed water flows downwards along the wall surface of the containment vessel 101 to the annular collector 105 under the action of gravity and then flows into the cooling water tank 103, so that natural circulation is formed. The core waste heat is conducted to the containment vessel 101 by means of the natural circulation flow, and the final heat sink of the natural circulation is the atmosphere. Because this waste heat discharge system is a closed natural circulation system, can run for a long time, continuously derive the reactor core waste heat.

The system provided by the invention realizes the discharge of the waste heat of the reactor core by adopting the passive technology, and has the advantages of strong heat discharge capability, simple system configuration, high reliability, long-term operation, no increase of the risk of radioactive substances on the external release and the like.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are merely exemplary embodiments of the present invention, and are not intended to limit the scope of the present invention, and any modifications, equivalent substitutions, improvements and the like made within the spirit and principle of the present invention should be included in the scope of the present invention.