WO2024060483A1

WO2024060483A1 - Nuclear power safety injection tank

Info

Publication number: WO2024060483A1
Application number: PCT/CN2023/074649
Authority: WO
Inventors: 刘建昌; 张拓益; 魏诗颖; 马小雅; 赵晓晗; 欧阳勇; 杨江; 李桂勇; 芮旻
Original assignee: 中广核研究院有限公司; 中国广核集团有限公司; 中国广核电力股份有限公司
Priority date: 2022-09-23
Filing date: 2023-02-06
Publication date: 2024-03-28
Also published as: CN115579159A

Abstract

A nuclear power safety injection tank (10), comprising a tank body (11), an isolation structure (12) and a regulating cylinder (13), wherein the tank body (11) is provided with a pressurizing port (111) at an upper end, and is provided with a flow-through port (112) at a lower end; the isolation structure (12) is arranged on an inner wall surface of the tank body (11) such that the space in the tank body (11) close to an inner side face is partitioned in a height direction so as to block liquid in the tank body (11); and the regulating cylinder (13) is vertically arranged at the bottom of the tank body (11), and has a lower end connected to the bottom of the tank body (11), regulating holes (131) are distributed in the regulating cylinder (13) in the height direction, and the flow-through port (112) communicates with the interior of the regulating cylinder (13).

Description

Safety injection box for nuclear power

Cross-references to related applications

This invention claims the priority of the Chinese patent application submitted to the Chinese Patent Office on September 23, 2022, with the application number 2022111667475 and the application name "Safety Injection Box for Nuclear Power", the entire content of which is incorporated into the present invention by reference.

Technical field

The invention relates to the field of nuclear power, and more specifically, to a safety injection box for nuclear power.

Background technique

The safety injection tank is an important special safety system of the pressurized water reactor nuclear power plant. In the event of a water loss accident, when the primary circuit pressure is lower than the safety injection tank injection pressure, the water in the safety injection tank will be released under the action of high-pressure nitrogen. It is injected into the primary loop through the injection pipeline to cool the reactor core.

Under external excitation conditions (such as wind, waves, ocean currents, etc.), offshore floating platforms or ships will tilt, rise and fall, sway, and other movements.

At this time, the water surface in the safety injection box of the nuclear power plant on the floating platform or ship will appear nonlinear sloshing phenomenon. In this case, the water in the safety injection box impacts the wall surface of the safety injection box, causing different effects on the inner wall of the safety injection box. When the impact pressure is relatively large, the sloshing phenomenon may directly harm the structural integrity of the safety injection tank.

technical problem

The technical problem to be solved by the present invention is to provide a safety injection box for nuclear power in view of the above-mentioned defects of the prior art.

Technical solutions

The technical solution adopted by the present invention to solve the technical problem is to construct a safety injection box for nuclear power, including a box body, an isolation structure, and an adjustment cylinder;

The upper end of the box is provided with a pressurization port, and the lower end is provided with a flow port;

The isolation structure is provided on the inner wall of the box to separate the space close to the inner side of the box in the height direction and block the liquid in the box;

The adjusting cylinder is erected at the bottom of the box, and its lower end is connected to the bottom of the box. Adjusting holes are distributed along the height direction on the adjusting cylinder, and the flow port is connected to the adjusting cylinder.

In some embodiments, the isolation structure includes a plurality of baffles distributed on the inner wall of the box.

In some embodiments, the baffle extends along the inner peripheral wall of the box.

In some embodiments, the baffles are divided into several groups, and the baffles of each group are arranged at intervals in the height direction of the box; and/or, the baffles of each group are arranged on the inner periphery of the box. Direction staggered setting.

In some embodiments, the baffles are closed in the inner circumferential direction of the box, and a plurality of the baffles are spaced apart in the height direction of the box.

In some embodiments, in the height direction of the box, the distance from the baffle closest to the pressure port to the pressure port is greater than a first preset distance, wherein the safety box is running The distance from the highest water level to the pressure port is the first preset distance; and/or,

In the height direction of the box, the distance from the baffle closest to the flow opening to the flow opening is greater than the second preset distance, wherein the distance from the isolation water level of the injection tank to the flow opening is the second preset distance.

In some embodiments, the baffle is arranged horizontally or inclined.

In some embodiments, the inner diameter of the adjustment barrel is larger than the hole diameter of the flow port.

In some embodiments, the upper end of the adjusting cylinder is closed, and the adjusting holes are distributed circumferentially on the side wall of the adjusting cylinder.

In some embodiments, the upper end of the box is provided with an upper detection port connected to the box to detect at least one of the water level and air pressure in the box; and/or the box The lower end is provided with a lower detection port connected to the box to detect at least one of water level and air pressure in the box.

beneficial effects

The safety injection box for nuclear power that implements the present invention has the following beneficial effects: the sloshing suppression partition structure proposed by the invention can ensure that when the water level changes after the safety injection box is put into operation, the sloshing phenomenon in the safety injection box can be effectively suppressed. Reduce the impact pressure of sloshing on the wall; at the same time, through the design of the regulating cylinder that can control the flow, the flow rate after the injection box is put into operation can be effectively controlled.

Description of the drawings

The present invention will be further described below in conjunction with the accompanying drawings and examples. In the accompanying drawings:

Figure 1 is a schematic cross-sectional structural diagram of a safety injection box for nuclear power in an embodiment of the present invention;

Figure 2 is a schematic cross-sectional structural diagram along the A-A direction in Figure 1.

Best Mode of Carrying Out the Invention

In order to have a clearer understanding of the technical features, purposes and effects of the present invention, the specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

As shown in Figures 1 and 2, the safety injection box 10 for nuclear power in a preferred embodiment of the present invention includes a box body 11, an isolation structure 12, and an adjustment cylinder 13. The upper end of the box body 11 is provided with a pressurization port 111, and the lower end is provided with a pressure port 111. The flow port 112, during the start-up phase of the nuclear power plant, is connected to the flow port 112 through the injection tank 10 to inject water into the body of the injection tank 10 and adjust it to a preset water level value.

The water level change in the safety injection tank 10 is monitored through a water level monitor. When the water level in the safety injection tank 10 reaches a preset value, water injection into the safety injection tank 10 is stopped. Further, high-pressure nitrogen gas is injected into the safety injection tank 10 through the pressure port 111, and the pressure changes in the safety injection tank 10 are monitored. When the pressure in the safety injection tank 10 reaches a preset value, the gas injection into the safety injection tank 10 is stopped.

At this time, isolate the pressure port 111, stop water injection, and open the isolation valve on the flow port 112 of the injection tank 10 and the primary circuit connecting pipe. When the injection tank 10 is started, the water in the injection tank 10 is injected into the reactor core through the flow port 112, and the outside of the flow port 112 is available for connecting pipes.

During the normal operation stage of the nuclear power plant, the primary circuit pressure is higher than the injection pressure of the safety injection tank 10, and the safety injection tank 10 is isolated from the primary circuit through a check valve. Under external excitation conditions, sloshing may occur in the injection box 10 .

Furthermore, the isolation structure 12 is provided on the inner wall of the box 11 to separate the space close to the inner side of the box 11 in the height direction. When the safety box 10 shakes, the isolation structure 12 can protect the box from impact. 11 The liquid on the inner wall blocks and slows down the flow, which can effectively suppress the sloshing phenomenon and ensure the integrity of the container.

When a water loss accident occurs, the primary circuit pressure drops rapidly. When the primary circuit pressure drops below the injection pressure of the safety injection tank 10, the water in the safety injection tank 10 is injected into the primary circuit through the safety injection pipeline driven by the pressure difference.

The regulating cylinder 13 is erected at the bottom of the box body 11, and the lower end is connected to the bottom of the box body 11. The side wall of the regulating cylinder 13 is provided with regulating holes 131 along the height direction, so that the liquid in the injection box 10 can flow into the regulating cylinder 13 through the regulating holes 131. The flow port 112 is connected to the regulating cylinder 13, and the liquid in the regulating cylinder 13 is injected into a circuit through the flow port 112.

As the injection progresses, the water level in the injection tank 10 gradually decreases, and the flow rate during the injection can be effectively adjusted through the small hole on the adjustment barrel 13 . Under external excitation conditions, sloshing will occur in the safety container 10. Under the action of the isolation structure 12, the sloshing phenomenon can be effectively suppressed to ensure the integrity of the container.

The sloshing suppression partition structure proposed by the present invention can ensure that when the water level changes after the safety injection box 10 is put into operation, it can effectively suppress the sloshing phenomenon in the safety injection box 10 and reduce the impact pressure of the sloshing on the wall; at the same time, it can control the flow rate The design of the regulating barrel 13 can effectively regulate the flow rate after the injection box 10 is put into operation.

In some embodiments, the isolation structure 12 includes a number of baffles 121 distributed on the inner wall surface of the box 11. The baffles 121 are used to block the liquid when the liquid in the injection tank 10 sloshes, thereby inhibiting the injection. The sloshing of the box 10 reduces the impact on the wall.

In this embodiment, the box body 11 is spherical. In order to match the inner wall surface of the box body 11, the baffle 121 is annular and is closed in the inner circumferential direction of the box body 11. The outer diameter of each layer of baffles 121 is equivalent to the inner diameter of the box body at the corresponding height position, and the inner hole diameter of each layer of baffles 121 is different. Preferably, the width of each layer of baffles 121 is the same, so that the blocking force of each layer of baffles 121 is more balanced.

A plurality of baffles 121 are spaced apart in the height direction of the box body 11, and the outer circle of the baffle 121 is connected to the inner wall surface of the box body 11, preferably by welding. In other embodiments, the baffle 121 can also be connected to the inner wall surface of the box body 11 by locking with fasteners.

The annular baffles 121 divide the inner wall of the box 11 into multiple layers, so that liquids at different water levels in the box 11 can be blocked by the baffles 121 to prevent sloshing.

Among them, in some embodiments, in the height direction of the box 11, the distance from the baffle 121 closest to the pressure port 111 to the pressure port 111 is greater than the first preset distance, in which the highest value when the safety box 10 is running is The distance from the water level to the pressure port 111 is the first preset distance. Specifically, in the height direction of the tank 11 , the baffle 121 located at the highest position is lower than the highest water level of the injection tank 10 . In this way, the baffle 121 located at the highest position can also block the liquid in the box.

In some embodiments, in the height direction of the box 11 , the distance from the baffle 121 closest to the flow opening 112 to the flow opening 112 is greater than the second preset distance, wherein the distance from the isolation water level of the safety tank 10 to the flow opening 112 is the second preset distance. Specifically, in the height direction of the box 11 , the baffle 121 located at the lowest position is higher than the isolation water level of the injection tank 10 . In this way, the baffle 121 located at the lowest position can also block the liquid in the box 11 .

Further, in some embodiments, in the height direction of the box 11 , the distance from the baffle 121 closest to the pressure port 111 to the pressure port 111 is greater than the first preset distance, and in the height direction of the box 11 , the distance from the baffle 121 closest to the flow opening 112 to the flow opening 112 is greater than the second preset distance. Specifically, the installation position of the highest position baffle 121 is slightly lower than the highest water level that may occur during normal operation of the safety injection tank 10, and the installation position of the lowest position baffle 121 is slightly higher than the isolation water level of the safety injection tank 10. When the injection box 10 is working, all the baffles 121 in the box 11 can play a blocking role.

In this embodiment, the baffles 121 are arranged horizontally to make the baffles 121 in each area in the circumferential direction more balanced. Of course, the baffles 121 can also be arranged at an angle, and the baffles 121 can also be arranged in various combinations. Here, No restrictions.

It is understandable that in other embodiments, the baffle 121 may also be extended along the inner circumferential wall of the box body 11. Preferably, the baffle 121 is in a fan-shaped ring shape, and the outer ring is connected to the inner wall surface of the box body 11 to block the sloshing of the liquid. In other embodiments, the baffle 121 may also be a plate-shaped or columnar structure of other shapes, as long as it can block the flow of liquid on the inner wall surface of the box body 11.

Further, when the baffles 121 are not circular, each baffle 121 of the isolation structure 12 can be divided into several groups, and each group of baffles 121 can be arranged regularly to allow the baffles 121 on the inner wall of the box 11 to be distributed. Evenly. The baffles 121 in each group are arranged according to specific rules. Specifically, the height positions of each group of baffles 121 can be the same and arranged along the inner circumferential direction, or they can be different and arranged along the height direction, or alternatively, the baffles 121 in each group can be arranged in the height direction. It can be arranged in a specific manner along the inner circumferential direction and height direction at the same time.

Each set of baffles 121 is arranged at intervals in the height direction of the box 11 to meet the requirements for blocking different liquid levels. Preferably, the upper and lower sets of baffles 121 are staggered in the inner circumferential direction of the box 11 to allow the isolation structure 12 to The blocking force can be provided in the inner circumferential direction of the box 11, providing a more balanced blocking force.

It can be understood that each group of baffles 121 is arranged at intervals in the height direction, and the upper and lower groups of baffles 121 are not staggered in the inner circumferential direction, or each group of baffles 121 is staggered in the inner circumferential direction, and the arrangement method in the height direction is not limited. Of course, each baffle 121 can also be arranged irregularly on the inner wall surface of the box body 11 to prevent the liquid in the box body 11 from sloshing.

In this embodiment, the regulating cylinder 13 is a cylindrical cylinder. Preferably, the upper end of the regulating cylinder 13 is closed. There are regulating holes 131 distributed along the circumferential direction on the side wall of the regulating cylinder 13 to allow the water outside the regulating cylinder 13 to be adjusted. The holes 131 flow into the regulating cylinder 13 to control the speed at which the liquid in the box 11 flows into the cylinder. The size, quantity, arrangement, etc. of the regulating holes 131 can be based on the minimum injection flow rate and effective injection of the injection box 10 time to design. As the liquid level decreases, under external excitation conditions, sloshing will occur in the safety tank 10. Under the action of the isolation structure 12, the sloshing phenomenon can be effectively suppressed to ensure the integrity of the container.

After the safety injection box 10 is started, the water level in the safety injection box 10 gradually decreases, and the adjustment hole 131 on the adjustment barrel 13 is gradually exposed, thus limiting the injection flow of the safety injection box 10 and extending the effective injection time of the safety injection box 10 .

The inner diameter of the regulating cylinder 13 is larger than the hole diameter of the circulation port 112, so that the water flowing out of the circulation port 112 can normally flow into the pipe outside the circulation port 112.

Further, the upper end of the box 11 is provided with an upper detection port 113 connected to the inside of the box 11 to detect at least one of the water level and air pressure in the box 11; and/or the lower end of the box 11 is provided with There is a lower detection port 114 connected to the box 11 to detect at least one of the water level and air pressure in the box 11 .

Specifically, in some embodiments, the upper end of the box 11 is provided with an upper detection port 113 connected to the inside of the box 11 . The upper detection port 113 can be connected to a water level measuring instrument and a pressure measuring instrument respectively to detect the pressure inside the box 11 The water level and air pressure; or, in some embodiments, the lower end of the box 11 is provided with a lower detection port 114 connected to the box 11, and the lower detection port 114 is connected to the water level measuring instrument and the pressure measuring instrument respectively to detect the box. The water level and air pressure in the box 11; or, in some embodiments, the upper and lower ends of the box 11 are respectively provided with an upper detection port 113 and a lower detection port 114 connected to the box 11. The upper detection port 113 can be connected to the pressure. The measuring meter is connected to detect the air pressure in the box 11 , and the lower detection port 114 can be connected to a water level measuring instrument to detect the water level in the box 11 .

It should be noted that the number of detection ports can be determined according to the requirements for water level and pressure measurement, and is not limited here.

The accuracy of the liquid level measurement of the present invention is improved. The baffle 121 effectively suppresses the sloshing phenomenon of the liquid level in the safety injection tank 10 and ensures that the water level in the safety injection tank 10 is maintained under the worst external excitation conditions. Within the range, by appropriately setting the location and number of detection ports, it is ensured that the water level measurement is not affected by sloshing, and the safety and reliability of the nuclear power plant are improved.

The openings on the regulating barrel 13 are distributed on the side wall, which can match the size and flow rate of the injection tank 10. No matter the water level in the injection tank 10 is high or low, there are openings at each position in the circumferential and height directions to allow outflow, reducing the It eliminates the influence of hole blocking and ensures the stability of water flow.

The invention can make the safety injection tank 10 have the ability to suppress the sloshing effect, maintain the stability of the free liquid surface, and have the ability to work normally and stably under conditions such as swinging under normal operation and accident conditions; and improve the safety and reliability of the equipment. ; Improve the accuracy of liquid level measurement in the safety tank 10 under ocean conditions and other conditions; realize that under accident conditions and when there is rocking motion, the water in the safety tank 10 can steadily drop and be injected into the core, extending the safety tank 10 years of service time, improving the reliability of accident post-accident treatment; enhancing the environmental adaptability of nuclear power plants and improving the economics of nuclear power plants.

The invention has the following advantages:

1. The structure of the present invention is simple, and the baffle 121 is welded and processed to facilitate manufacturing.

2. The present invention does not limit the shape and application scenarios of the safety tank 10, nor does it limit the applicable reactor type and layout location; it is more suitable for offshore reactors.

3. By setting the baffle 121 in the present invention, the movement of the liquid is hindered under the up-and-down swinging condition, thereby reducing the sloshing effect and reducing the impact force on the upper and lower walls. The left and right swinging condition stratifies the liquid axially, reducing the radial flow rate to a certain extent, and effectively improves the safety and reliability of the injection tank 10 .

4. The present invention can stabilize the water level in the injection tank 10 during normal operation, reduce the kinetic energy of the liquid in the injection tank 10, alleviate the impact force on the box body 11 of the injection tank 10, and improve the reliability of the equipment. Under accident conditions, the check valve is opened, and while the water level in the injection tank 10 drops, the stability of the liquid level around the regulating cylinder 13 is guaranteed, and the injection flow rate is kept steadily decreasing, which is convenient for the controllable means of accident relief.

5. The application of the present invention improves the reliability of the safety injection box 10 and the box body 11 during normal operation. Improving the ability of nuclear power plants to handle accidents in harsher environments enhances the environmental adaptability of nuclear power plants and improves the economics of nuclear power plants.

It can be understood that the above technical features can be used in any combination without limitation.

The above are only examples of the present invention, and do not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the description and drawings of the present invention, or directly or indirectly applied to other related technologies fields are equally included in the scope of patent protection of the present invention.

Claims

A safety injection box for nuclear power, which is characterized in that it includes a box body (11), an isolation structure (12), and an adjustment cylinder (13);

The upper end of the box (11) is provided with a pressure port (111), and the lower end is provided with a flow port (112);

The isolation structure (12) is arranged on the inner wall surface of the box (11) to separate the space close to the inner side of the box (11) in the height direction, so as to isolate the space inside the box (11). Liquid blocks;

The adjusting barrel (13) is erected at the bottom of the box (11), and its lower end is connected to the bottom of the box (11). There are adjustment holes (131) distributed along the height direction on the adjusting barrel (13). , the flow port (112) is connected to the regulating cylinder (13).
The safety injection box for nuclear power according to claim 1, characterized in that the isolation structure (12) includes a number of baffles (121) distributed on the inner wall surface of the box (11).
The safety injection box for nuclear power according to claim 2, characterized in that the baffle (121) extends along the inner peripheral wall of the box (11).
The safety injection box for nuclear power according to claim 2, characterized in that the baffles (121) are divided into several groups, and the baffles (121) of each group are arranged at intervals in the height direction of the box (11). cloth; and/or, each group of baffles (121) is staggered in the inner circumferential direction of the box (11).
The safety injection box for nuclear power according to claim 2, characterized in that the baffle (121) is closed in the inner circumferential direction of the box (11), and a plurality of the baffles (121) are arranged in the inner circumferential direction of the box (11). The boxes (11) are spaced apart in the height direction.
The safety box for nuclear power according to any one of claims 2 to 5, characterized in that, in the height direction of the box (11), the baffle closest to the pressure port (111) (121) The distance to the pressure port (111) is greater than the first preset distance, wherein the distance from the highest water level when the safety tank (10) is running to the pressure port (111) is the first a preset distance; and/or

In the height direction of the box body (11), the distance between the baffle (121) closest to the circulation port (112) and the circulation port (112) is greater than a second preset distance, and the distance between the isolation water level of the injection box (10) and the circulation port (112) is the second preset distance.
The safety box for nuclear power according to any one of claims 2 to 5, characterized in that the baffle (121) is arranged horizontally or inclined.
The safety box for nuclear power according to any one of claims 1 to 5, characterized in that the inner diameter of the adjustment barrel (13) is larger than the aperture of the flow port (112).
The safety box for nuclear power according to any one of claims 1 to 5, characterized in that the upper end of the adjustment barrel (13) is closed, and the side walls of the adjustment barrel (13) are distributed along the circumferential direction. Said adjusting hole (131).
The safety box for nuclear power according to any one of claims 1 to 5, characterized in that the upper end of the box (11) is provided with an upper detection port (113) connected to the inside of the box (11). , to detect at least one of the water level and air pressure in the box (11); and/or

The lower end of the box (11) is provided with a lower detection port (114) connected to the box (11) to detect at least one of the water level and air pressure in the box (11).