CN219180197U - Small pressurized water reactor nitrogen pressure stabilizing system and containment device - Google Patents

Abstract

The utility model discloses a nitrogen pressure stabilizing system and a containment device of a small pressurized water reactor, relates to a nitrogen pressure stabilizing system of a small pressurized water reactor, is used for maintaining the pressure stability in a pressure container and mainly comprises a nitrogen pressure stabilizer and a nitrogen tank. The nitrogen pressure stabilizer is connected with the pressure vessel through a fluctuation pipe and is positioned at one horizontal side of the pressure vessel, and the nitrogen pressure stabilizer comprises cooling water and nitrogen; the nitrogen tank is connected with the nitrogen voltage stabilizer through a pipeline, a quick-closing valve is arranged on the pipeline, and the nitrogen tank can supply or recycle nitrogen into the nitrogen voltage stabilizer. Because this application has utilized nitrogen gas compressible from steady voltage characteristic, simultaneously, does not have equipment such as water tank and connecting tube of ann notes to reduced the return circuit coolant and revealed the risk, because nitrogen gas stabiliser has not put in the high position but is located pressure vessel's horizontal one side, so improved the utilization ratio of lower part space, the upper portion space can save down, so whole safe shell volume has obtained the reduction, is favorable to radiation shielding design, has also reduced economic cost.

Description

Small pressurized water reactor nitrogen pressure stabilizing system and containment device

Technical Field

The utility model relates to the field of primary loop coolant safety control systems of nuclear power stations, in particular to a small pressurized water reactor nitrogen pressure stabilizing system and a containment device.

Background

In a nuclear power plant reactor, the main function of the pressurizer is to maintain and control a loop pressure within a design range during steady state and transient operation of the reactor, and to prevent saturated boiling and overpressure of a loop coolant. The common types of voltage stabilizer are steam voltage stabilizer and gas voltage stabilizer, and nitrogen voltage stabilizer among the gas voltage stabilizer is comparatively common again, and nitrogen voltage stabilizer possesses pressure control function, volume compensation function and passive reactor core emergency cooling function.

In the prior art, when a water loss accident occurs in a reactor coolant system, water needs to be injected into a pressure vessel to maintain the reactor core submerged, so that the reactor core damage caused by the reactor core exposure is prevented. For passive safety injection mode, the safety water tank can be provided with a communication pipeline with the nitrogen pressure stabilizer and the pressure vessel, the first time causes a plurality of equipment pipelines in the containment, the second passive safety water tank and the nitrogen pressure stabilizer occupy the internal space of the containment of the reactor respectively, the volume of the containment is greatly increased, the design of secondary radiation shielding of the offshore small-sized reactor is not only facilitated, the danger is increased, and the reduction of economic cost is also not facilitated.

Disclosure of Invention

Based on the problems, such as difficult design and high cost of secondary radiation shielding due to the large volume of equipment in a containment, a small pressurized water reactor nitrogen pressure stabilizing system is needed. Comprising the following steps:

the nitrogen pressure stabilizer is connected with the pressure vessel through a fluctuation pipe and is positioned at one horizontal side of the pressure vessel, and cooling water and nitrogen are contained in the nitrogen pressure stabilizer;

the nitrogen tank is connected with the nitrogen voltage stabilizer through a pipeline, a quick-closing valve is arranged on the pipeline, and the nitrogen tank can supply or recycle nitrogen into the nitrogen voltage stabilizer.

In one embodiment, a heat exchange cooler is further included and is configured to regulate the normal operating temperature of the cooling water to 40 to 55 degrees celsius.

In one embodiment, the nitrogen tank is provided with a compressor, the compressor is used for compressing and supplying air to the nitrogen tank, and the highest pressure in the compressor is lower than the design pressure of the nitrogen tank.

In one embodiment, the nitrogen tank is provided with a plurality of groups, and the groups are independently designed in parallel, and are mutually provided with communication isolation valves.

In one embodiment, multiple sets of nitrogen tanks are each configured with a pressure gauge.

In one embodiment, a restrictor is provided at the connection interface of the nitrogen pressurizer and the pressure vessel, and the restrictor is used for controlling the flow of the coolant.

In one embodiment, the nitrogen pressure stabilizer is provided with two groups and is distributed along the circumferential direction of the pressure vessel.

In one embodiment, both sets of nitrogen pressure regulators are provided with a water level gauge for measuring the cooling water capacity within the nitrogen pressure regulators.

In one embodiment, one end of the surge tube extends below the level of the cooling water within the nitrogen pressure regulator.

The application also provides a containment device, which is characterized in that besides the small pressurized water reactor nitrogen pressure stabilizing system in the embodiment, the containment device further comprises a containment and a pressure container, and the pressure container and the small pressurized water reactor nitrogen pressure stabilizing system are arranged in the containment.

The small pressurized water reactor nitrogen pressure stabilizing system is used for maintaining the pressure stability inside the pressure container and mainly comprises a nitrogen pressure stabilizer and a nitrogen tank. The nitrogen pressure stabilizer is connected with the pressure vessel through a fluctuation pipe and is positioned at one horizontal side of the pressure vessel, and the nitrogen pressure stabilizer comprises cooling water and nitrogen; the nitrogen tank is connected with the nitrogen voltage stabilizer through a pipeline, a quick-closing valve is arranged on the pipeline, and the nitrogen tank can supply or recycle nitrogen into the nitrogen voltage stabilizer.

When the reactor normally operates, the power of the reactor is basically maintained at the rated power, and the nitrogen pressure stabilizer is communicated with the reactor pressure vessel through a fluctuation pipe; the quick-opening valve of the nitrogen tank is opened and communicated with the pressure stabilizer, and the average temperature of the reactor coolant basically has no change, so that larger shrinkage and expansion cannot be caused, the volume of the gas space and the volume of the nitrogen tank of the nitrogen pressure stabilizer are changed less, and the normal operating pressure is basically maintained unchanged. Under normal transient state, the running mode of the small pressurized water reactor nitrogen pressure stabilizing system is consistent with that of steady state running, and the nitrogen pressure stabilizer (and the nitrogen tank) is used for coping with shrinkage and expansion of the reactor coolant through gas compressibility (self-stabilization), so that the pressure of the reactor coolant is controlled, and the integral boiling of a reactor core caused by too low pressure or the damage of reactor coolant system equipment caused by too high pressure is avoided. When an accident occurs, nitrogen can be injected into the nitrogen stabilizer by the nitrogen tank, the quantity of the nitrogen is increased, the volume is increased, and cooling water is extruded to enter the pressure vessel for cooling, or high-temperature coolant in the reactor enters the water side of the nitrogen stabilizer, and the nitrogen stabilizer can absorb part of heat. Because this application has utilized nitrogen gas compressible from steady voltage characteristic, simultaneously, does not have equipment such as water tank and connecting tube of ann notes to reduced the return circuit coolant and revealed the risk, because nitrogen gas stabiliser has not put in the high position but is located pressure vessel's horizontal one side, so improved the utilization ratio of lower part space, the upper portion space can save down, so whole safe shell volume has obtained the reduction, is favorable to radiation shielding design, has also reduced economic cost.

Drawings

FIG. 1 is a schematic diagram of the connection of a small pressurized water reactor nitrogen stabilization system and a pressure vessel in one embodiment of the present application.

Reference numerals: a pressure vessel 110; a nitrogen pressure stabilizer 120; a surge tube 130; a nitrogen tank 140; a compressor 150; a pressure gauge 01; a water level measuring instrument 02; a quick-closing valve 10; communicating with the isolation valve 20.

Detailed Description

In order that the above objects, features and advantages of the utility model will be readily understood, a more particular description of the utility model will be rendered by reference to the appended drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present utility model. The present utility model may be embodied in many other forms than described herein and similarly modified by those skilled in the art without departing from the spirit of the utility model, whereby the utility model is not limited to the specific embodiments disclosed below.

In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings are merely for convenience in describing the present utility model and simplifying the description, and do not indicate or imply that the device or element being referred to must have a specific orientation, be configured and operated in a specific orientation, and therefore should not be construed as limiting the present utility model.

Furthermore, the terms "first," "second," and the like, are used for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In the description of the present utility model, the meaning of "plurality" means at least two, for example, two, three, etc., unless specifically defined otherwise.

In the present utility model, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

In the present utility model, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

It will be understood that when an element is referred to as being "fixed" or "disposed" on another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.

Referring to FIG. 1, FIG. 1 is a schematic diagram of the connection of a small pressurized water reactor nitrogen stabilization system to a pressure vessel 110; the application provides a small pressurized water reactor nitrogen pressure stabilizing system, which mainly comprises a nitrogen pressure stabilizer 120 and a nitrogen tank 140, wherein the nitrogen pressure stabilizer 120 is connected with a pressure vessel 110 through a fluctuation pipe 130, the nitrogen pressure stabilizer 120 is positioned on one horizontal side of the pressure vessel 110, and cooling water and nitrogen are contained in the nitrogen pressure stabilizer 120; the nitrogen tank 140 is connected with the nitrogen pressure stabilizer 120 through a pipeline, the pipeline is provided with a quick-closing valve 10, and the nitrogen tank 140 can supply or recycle nitrogen into the nitrogen pressure stabilizer 120.

Referring to fig. 1, in one embodiment, the small pressurized water reactor nitrogen stabilization system includes a nitrogen stabilizer 120 and a nitrogen tank 140, the nitrogen stabilizer 120 being connected to the pressure vessel 110 through a surge tube 130. The nitrogen gas pressure stabilizer 120 is positioned at a horizontal side of the pressure vessel 110, and in a stable state, about 70% of cooling water and about 30% of nitrogen gas are contained in the nitrogen gas pressure stabilizer 120; the nitrogen tank 140 is connected with the nitrogen pressure stabilizer 120 through a pipeline, two quick-closing valves 10 are arranged on the pipeline, the nitrogen tank 140 can supply or recycle nitrogen into the nitrogen pressure stabilizer 120, and the two quick-closing valves 10 can better cope with pipeline breakage.

When the reactor is in normal operation, the reactor power is basically maintained at the rated power, and the nitrogen pressure stabilizer 120 is communicated with the reactor pressure vessel 110 through the fluctuation pipe 130; the quick-opening valve of the nitrogen tank 140 is opened and communicated with the nitrogen pressure stabilizer 120, and the average temperature of the reactor coolant is basically unchanged, so that larger shrinkage and expansion cannot be caused, the volume of the gas space of the nitrogen pressure stabilizer 120 and the volume of the nitrogen tank 140 are less changed, and the normal operating pressure is basically maintained unchanged. Under normal transient conditions, the operation mode of the small pressurized water reactor nitrogen pressure stabilizing system is consistent with that of steady-state operation, and the nitrogen pressure stabilizer 120 (and the nitrogen tank 140) is used for coping with the shrinkage and expansion of the reactor coolant through gas compressibility (self-stabilization), so that the pressure of the reactor coolant is controlled, and the integral boiling of a reactor core caused by too low pressure or the damage of reactor coolant system equipment caused by too high pressure is avoided. In the event of an accident, the nitrogen tank 140 may inject nitrogen into the nitrogen pressure stabilizer 120, and the nitrogen factor increases to increase the volume, thereby extruding cooling water into the pressure vessel 110 for cooling, or high temperature coolant in the reactor enters the water side of the nitrogen pressure stabilizer 120, and the nitrogen pressure stabilizer 120 may absorb part of heat. Because this application has utilized nitrogen gas compressible from steady voltage characteristic, simultaneously, does not have equipment such as water tank and connecting tube of ann notes to reduced the return circuit coolant and revealed the risk, because nitrogen gas stabiliser 120 has not put in the high position but is located pressure vessel 110's horizontal one side, so improved the utilization ratio of lower part space, the upper space can save down, so whole safe shell volume has obtained the reduction, is favorable to radiation shielding design, has also reduced economic cost.

In the above embodiment, the nitrogen pressure stabilizer 120 adopts the passive design, and is independent of external power supply and active equipment, such as an electric heater and a safety valve, so that the self-pressure stabilization is completely realized. Meanwhile, no electric heater is designed, so that the minimum water volume exposed by the electric heater is not needed to be considered, the volumetric efficiency is higher, and accidents related to the safety valve, such as three-island accidents in the United states, can be avoided without the design of the safety valve. The nitrogen pressure stabilization can have the passive safety injection function, and the emergency cooling function of the reactor core is executed.

In one embodiment, a heat exchange cooler (not shown) is further included, and the heat exchange cooler is configured to cool water at a normal operating temperature of 40 to 55 degrees celsius.

In one embodiment, the nitrogen voltage stabilizer 120 is provided with a heat exchange cooler, the heat exchange cooler is configured to enable the normal operation temperature of cooling water to be 40-55 ℃, preferably 50 ℃, the temperature can be adjusted to be 40 ℃ downwards or 55 ℃ upwards according to different requirements, the gas-water volume characteristic of about 50 ℃ can keep high heat storage capacity, and the risks of operation transient of a loop and overpressure of non-LOCA (Loss of Coolant Accident ) can be effectively relieved.

Referring to fig. 1, in one embodiment, the apparatus further includes a compressor 150, the compressor 150 is configured to compress the gas for the nitrogen tank 140, and the highest pressure in the compressor 150 is lower than the design pressure of the nitrogen tank 140.

Referring to fig. 1, in one embodiment, the system further includes a compressor 150, the compressor 150 is connected to the nitrogen tank 140, the compressor 150 can supply air to the nitrogen tank 140 to meet the air requirement of the nitrogen pressure stabilizer 120, and the highest pressure in the compressor 150 is lower than the design pressure of the nitrogen tank 140, so as to avoid accidents caused by overpressure of the nitrogen tank 140.

Referring to fig. 1, in one embodiment, the nitrogen tank 140 is provided with multiple sets of independent parallel designs, with the multiple sets of communication isolation valves 20 being provided with each other.

Referring to fig. 1, in one embodiment, two sets of nitrogen tanks 140 are provided, and are independently connected in parallel, so that nitrogen is received and released into the nitrogen voltage stabilizer 120 in a one-to-one correspondence manner, and a communication isolation valve 20 is provided between the two sets of nitrogen tanks 140.

Preferably, in other embodiments, the nitrogen tanks 140 are divided into three groups, two of which use one standby, and the communication isolation valves 20 are provided between each group, which may be standby.

Referring to fig. 1, in one embodiment, the plurality of sets of nitrogen tanks 140 are each configured with a pressure gauge 01, and the pressure gauge 01 is capable of measuring the current pressure in the nitrogen tank 140 and the nitrogen pressure regulator 120, and controlling the nitrogen capacity in the nitrogen pressure regulator 120 according to the pressure.

Preferably, each set of nitrogen tanks 140 may be set at different pressures, which may be controlled and adjusted by compressor 150 according to different operating conditions.

Referring to fig. 1, in one embodiment, a flow restrictor (not shown) is provided at the interface of the nitrogen regulator 120 and the pressure vessel 110, and may control the flow of coolant and cooling water in the event of a LOCA accident.

In one embodiment, the nitrogen pressure stabilizer 120 is provided in two sets and is arranged along the circumferential direction of the pressure vessel 110.

In one embodiment, the nitrogen stabilizers 120 are distributed and arranged in two groups independently, the distances between the two groups of nitrogen stabilizers 120 and the pressure vessel 110 are the same, and the two groups of nitrogen stabilizers 120 have passive safety injection capability and execute a reactor core emergency cooling function if necessary; the distributed arrangement of the nitrogen pressure stabilizer 120 can reduce the size of the surge tube 130 and increase the safety characteristics.

Preferably, no connection pipe is connected between the water sides of the two sets of nitrogen pressure regulators 120, when the surge pipe 130 breaks, the cooling water in one set of nitrogen pressure regulators 120 may flow back to the broken surge pipe 130, so that the cooling water in the intact nitrogen pressure regulator 120 cannot be injected into the reactor core, and the connection pipe connection of the water sides is omitted, so that passive safety injection of the surge pipe 130 under a water loss accident is facilitated.

In one embodiment, both sets of nitrogen pressure regulators 120 are provided with a water level meter 02, and the water level meter 02 is used to measure the cooling water capacity within the nitrogen pressure regulators 120, so that the capacity of the nitrogen and whether the replenishment or the discharge is required can be determined.

Referring to FIG. 1, in one embodiment, one end of a surge tube 130 extends below the level of the cooling water within the nitrogen pressurizer 120.

Referring to fig. 1, in one embodiment, one end of the surge tube 130 extends below the cooling water level inside the nitrogen regulator 120, the surge tube 130 is below the cooling water level, and when the cooling water needs to be replenished, the increased volume of nitrogen can conveniently push the cooling water into the surge tube 130 to reach the pressure vessel 110.

The application also provides a containment device, which is characterized by comprising a containment and a pressure vessel 110, wherein the pressure vessel 110 and the small pressurized water reactor nitrogen pressure stabilizing system are arranged in the containment besides the small pressurized water reactor nitrogen pressure stabilizing system in the embodiment.

The technical features of the above-described embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above-described embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.

The above examples illustrate only a few embodiments of the utility model, which are described in detail and are not to be construed as limiting the scope of the utility model. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the utility model, which are all within the scope of the utility model. Accordingly, the scope of protection of the present utility model is to be determined by the appended claims.

Claims (10)

1. A small pressurized water reactor nitrogen pressure stabilizing system for maintaining pressure stability of a pressure vessel (110), comprising:

the nitrogen pressure stabilizer (120), the nitrogen pressure stabilizer (120) is connected with the pressure vessel (110) through a fluctuation pipe (130), the nitrogen pressure stabilizer (120) is positioned on one horizontal side of the pressure vessel (110), and cooling water and nitrogen are contained in the nitrogen pressure stabilizer (120);

the nitrogen tank (140), nitrogen tank (140) pass through the pipeline with nitrogen voltage stabilizer (120) are connected, be equipped with on the pipeline and close valve (10 soon, nitrogen tank (140) can supply or retrieve nitrogen gas in nitrogen voltage stabilizer (120).

2. The compact pressurized water reactor nitrogen stabilization system of claim 1, further comprising a heat exchange cooler configured to regulate a normal operating temperature of the cooling water to 40 to 55 degrees celsius.

3. The pressurized water reactor nitrogen stabilization system of claim 1 further comprising a compressor (150), the compressor (150) configured to compress the gas supply to the nitrogen tank (140), the highest pressure within the compressor (150) being lower than the design pressure of the nitrogen tank (140).

4. The nitrogen stabilization system of a small pressurized water reactor according to claim 1, wherein the nitrogen tank (140) is provided with a plurality of groups, and the groups are independently designed in parallel, and the plurality of groups are mutually provided with communication isolation valves (20).

5. The pressurized water reactor nitrogen stabilization system of claim 4, wherein a plurality of sets of said nitrogen tanks (140) are each configured with a pressure gauge (01).

6. The pressurized-water reactor nitrogen stabilization system according to claim 1, characterized in that a flow restrictor is provided at the connection interface of the nitrogen stabilizer (120) and the pressure vessel (110), said flow restrictor being used for controlling the flow of coolant.

7. The pressurized water reactor nitrogen pressure stabilizer system according to claim 1, wherein the nitrogen pressure stabilizer (120) is provided with two groups and is arranged along the circumferential direction of the pressure vessel (110).

8. The small pressurized water reactor nitrogen pressure stabilizing system according to claim 7, wherein both sets of nitrogen pressure stabilizers (120) are provided with a water level meter (02) for measuring the cooling water capacity in the nitrogen pressure stabilizers.

9. The pressurized water reactor nitrogen stabilization system of claim 1, wherein one end of the surge tube (130) extends below the cooling water level inside the nitrogen stabilizer (120).

10. A containment device comprising, in addition to the small pressurized water reactor nitrogen pressure stabilization system of any one of claims 1 to 9, a containment and a pressure vessel (110), said pressure vessel (110) and said small pressurized water reactor nitrogen pressure stabilization system being disposed within said containment.

Images