Device and method for maintaining micro-positive pressure of primary circuit of high-temperature gas cooled reactor

Abstract

The invention relates to the technical field of reactor operation, in particular to a device and a method for maintaining micro-positive pressure of a primary loop of a high-temperature gas cooled reactor. Comprising a helium purification system, the outlet end of the helium purification system is communicated with a loop through a first pipeline, and a first adjusting valve is arranged on the first pipeline; the helium storage tanks are communicated with the inlet end of the helium purification system through a second pipeline, and a second adjusting valve is arranged on the second pipeline; a first pressure sensor is arranged in the first loop and is suitable for monitoring first air pressure in the first loop in real time. According to the application, the opening degree of the first adjusting valve can be adjusted firstly, gas is supplemented to the primary loop through the helium purification system, and when the helium purification system cannot maintain the micro-positive pressure in the primary loop, the opening degree of the second adjusting valve can be adjusted, so that the micro-positive pressure in the primary loop is maintained.

Description

Technical Field

[0001] The present invention relates to the technical field of reactor operation, and particularly relates to a device and method for maintaining a slightly positive pressure in the primary circuit of a high-temperature gas-cooled reactor. Background Art

[0002] The primary coolant of a high-temperature gas-cooled reactor is helium. During reactor overhaul or certain special maintenance periods, maintenance work needs to be carried out on the relevant equipment in the primary circuit, and openings will be made on the operation surface of the primary circuit. To prevent the uncontrollable external leakage of the primary coolant after the opening and prevent air from entering the primary circuit and affecting the helium purity, the primary circuit needs to be placed in a slightly positive pressure state.

[0003] During the current maintenance work, the openings on the operation surface will be blocked, but the sealing performance is low, and the permeation ability of helium is stronger than that of general gases, so it is easy to leak to the outside. If the maintenance period is long, it may lead to the balance of the pressure in the primary circuit and the atmospheric pressure, thus allowing external air to enter the primary circuit. Summary of the Invention

[0004] In view of this, the present invention provides a device and method for maintaining a slightly positive pressure in the primary circuit of a high-temperature gas-cooled reactor to solve the problem that the existing method of blocking the openings on the operation surface is prone to causing helium pollution.

[0005] In a first aspect, the present invention provides a device for maintaining a slightly positive pressure in the primary circuit of a high-temperature gas-cooled reactor, including:

[0006] A helium purification system, the outlet end of which is connected to the primary circuit through a first pipeline, and a first regulating valve is arranged on the first pipeline;

[0007] Multiple helium storage tanks, which are connected to the inlet end of the helium purification system through a second pipeline, and a second regulating valve is arranged on the second pipeline;

[0008] A first pressure sensor is arranged in the primary circuit and is adapted to monitor the first air pressure in the primary circuit in real time.

[0009] In this application, the opening degree of the first regulating valve can be adjusted first, and the primary circuit can be supplemented with gas through the helium purification system. When the helium purification system cannot maintain a slightly positive pressure in the primary circuit, the opening degree of the second regulating valve can be adjusted to maintain a slightly positive pressure in the primary circuit. The helium purification system and the helium storage tanks are used as gas supplement sources, and a two-stage gas supplement link can be formed to realize the staged regulation of the pressure of the gas supplement sources. Maintaining a slightly positive pressure in the primary circuit can keep the leakage of helium within an acceptable range and avoid the pollution of helium in the primary circuit at the same time. The first pressure sensor can monitor whether the pressure in the primary circuit is in a slightly positive pressure.

[0010] In an optional embodiment, the helium storage tank includes:

[0011] The main helium storage tank and other helium storage tanks other than the main helium storage tank. The main helium storage tank is connected to the helium purification system through a second pipeline, and the other helium storage tanks are connected to the main helium storage tank through a third pipeline. The main helium storage tank can be used as the main air replenishment source. The other helium storage tanks replenish the main helium storage tank, and the main helium storage tank can further replenish the helium purification system.

[0012] In an alternative embodiment, the main helium storage tank is the smallest helium storage tank, and a second pressure sensor is provided inside the main helium storage tank, which is adapted to monitor the second air pressure inside the main helium storage tank in real time. The second pressure sensor can monitor whether the air pressure inside the main helium storage tank is greater than a slightly positive pressure, so that helium can be smoothly replenished into the primary loop. The main helium storage tank being the smallest helium storage tank facilitates controlling the replenishment of the main helium storage tank into the helium purification system.

[0013] In an alternative embodiment, a first isolation valve is provided on the third pipeline. This facilitates the direct replenishment of the helium purification system by the main helium storage tank without interference from other helium storage tanks.

[0014] In an alternative embodiment, the first pipeline is connected to the other helium storage tanks through a fourth pipeline. The connection point of the first pipeline and the fourth pipeline is located at one end of the first regulating valve away from the helium purification system, and a second isolation valve is provided on the fourth pipeline.

[0015] In an alternative embodiment, a membrane compressor is provided on the fourth pipeline, and the membrane compressor is arranged between the second isolation valve and the other helium storage tanks. The membrane compressor can pump some of the original helium gas in the helium purification system and the main helium storage tank into the other helium storage tanks, reducing the original air pressure in the helium purification system and the main helium storage tank.

[0016] In an alternative embodiment, a third isolation valve is provided on the second pipeline, and the third isolation valve is located between the second regulating valve and the main helium storage tank. This can isolate the helium purification system and the main helium storage tank.

[0017] In an alternative embodiment, a fourth isolation valve is provided on the first pipeline, and the fourth isolation valve is located between the fourth pipeline and the primary loop. This can isolate the primary loop from the membrane compressor and the helium purification system respectively.

[0018] In an alternative embodiment, the first regulating valve, the second regulating valve, the first isolation valve, the second isolation valve, the third isolation valve, and the fourth isolation valve are all electric valves. This facilitates the automatic control of the opening degrees of the first regulating valve and the second regulating valve, as well as the opening and closing of the first isolation valve, the second isolation valve, the third isolation valve, and the fourth isolation valve.

[0019] Second aspect, the present invention also provides a method for maintaining a slightly positive pressure in the primary circuit of a high-temperature gas-cooled reactor, which is applicable to the device for maintaining a slightly positive pressure in the primary circuit of a high-temperature gas-cooled reactor as described above, and includes the following steps:

[0020] S1. Close the first isolation valve and the fourth isolation valve, open the first regulating valve, the second regulating valve, the second isolation valve, the third isolation valve and the membrane compressor, so that the second air pressure is higher than the slightly positive pressure;

[0021] S2. Close the second regulating valve, the second isolation valve, the third isolation valve, the first regulating valve and the membrane compressor, open the fourth isolation valve, and adjust the opening degree of the first regulating valve so that the first air pressure maintains the slightly positive pressure;

[0022] S3. If the first air pressure cannot maintain the slightly positive pressure when the opening degree of the first regulating valve is adjusted to the maximum, open the third isolation valve and adjust the opening degree of the second regulating valve so that the first air pressure maintains the slightly positive pressure;

[0023] S4. If the first air pressure cannot maintain the slightly positive pressure when the opening degree of the second regulating valve is adjusted to the maximum, first close the second regulating valve and the third isolation valve, open the first isolation valve so that the second air pressure is higher than the slightly positive pressure, then close the first isolation valve, open the third isolation valve, and adjust the opening degree of the second regulating valve so that the first air pressure maintains the slightly positive pressure.

[0024] In this application, the primary circuit can be supplemented with helium gas in the helium purification system first. If the helium purification system cannot maintain the slightly positive pressure state of the primary circuit, the helium purification system is supplemented with helium gas from the main helium storage tank. If the main helium storage tank cannot maintain the slightly positive pressure state of the primary circuit either, the main helium storage tank is first supplemented with helium gas from other helium storage tanks, and then the helium purification system is supplemented with helium gas from the main helium storage tank, so that the primary circuit maintains the slightly positive pressure state. The slightly positive pressure state of the primary circuit can be maintained in stages. Description of the Drawings

[0025] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for use in the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0026] Figure 1 It is a schematic structural diagram of Embodiment 1 of the present invention;

[0027] Figure 2 It is a schematic principle diagram of Embodiment 2 of the present invention.

[0028] Description of the Reference Numerals:

[0029] 1. Helium purification system; 2. First pipeline; 3. Primary loop; 4. First regulating valve; 5. Second pipeline; 6. Second regulating valve; 7. Main helium storage tank; 8. Other helium storage tanks; 9. Third pipeline; 10. First isolation valve; 11. Fourth pipeline; 12. Second isolation valve; 13. Membrane compressor; 14. Third isolation valve; 15. Fourth isolation valve. Detailed implementation manners

[0030] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0031] The coolant of the primary loop of a high-temperature gas-cooled reactor is helium. Helium is an inert gas with good heat transfer and heat-carrying performance, a small neutron capture cross-section, and no phase change, having the properties desired for a reactor coolant. During major overhauls or certain special maintenance periods of the reactor, maintenance work needs to be carried out on the equipment related to the primary loop, and openings will be made on the working surface of the primary loop. To prevent uncontrollable external leakage of the primary loop coolant after the opening and to prevent air from entering the primary loop and affecting the helium purity, the primary loop should be placed in a slightly positive pressure state.

[0032] Although the openings on the working surface will be sealed during the maintenance work, the sealing performance is not satisfactory, and the penetration ability of helium is stronger than that of ordinary gases and it is very easy to leak to the outside. If the maintenance period is relatively long, it may cause the pressure in the primary loop to balance with the atmospheric pressure, thus allowing external air to enter the primary loop. Therefore, the slightly positive pressure of the primary loop should be maintained during the maintenance of the primary loop opening to always ensure that the primary loop is in a slightly positive pressure state.

[0033] The following will be combined with Figures 1 to 2 , to describe the embodiments of the present invention.

[0034] Embodiment 1

[0035] According to an embodiment of the present invention, as shown in the attached Figure 1 , a device for maintaining a slightly positive pressure in the primary loop of a high-temperature gas-cooled reactor is provided, including:

[0036] A helium purification system 1, the outlet end of the helium purification system 1 is connected to the primary loop 3 through a first pipeline 2, and a first regulating valve 4 is provided on the first pipeline 2;

[0037] Helium storage tanks, there are multiple, and are connected to the inlet end of the helium purification system 1 through a second pipeline 5, and a second regulating valve 6 is provided on the second pipeline 5;

[0038] It should be noted that there is a certain amount of helium in the helium purification system 1 and the helium storage tank for the normal daily use of the reactor, and the air pressure is significantly higher than the slightly positive pressure. The slightly positive pressure refers to the air pressure slightly higher than the atmospheric pressure, which can be a specific value or a certain air pressure range.

[0039] A first pressure sensor is provided in the primary loop 3, which is suitable for real-time monitoring of the first air pressure in the primary loop 3.

[0040] This application may also include a controller, and the first regulating valve 4, the second regulating valve 6, the first isolation valve 10, the second isolation valve 12, the third isolation valve 14, the fourth isolation valve 15, the first pressure sensor, the second pressure sensor, and the membrane compressor 13 can all be connected to the controller. The rate of air replenishment can be controlled through the controller.

[0041] In this application, the opening of the first regulating valve 4 can be adjusted first, and the primary loop 3 is replenished with air through the helium purification system 1. When the helium purification system 1 cannot maintain a slightly positive pressure in the primary loop 3, the opening of the second regulating valve 6 can be adjusted to maintain a slightly positive pressure in the primary loop 3. The helium purification system 1 and the helium storage tank serve as air replenishment sources, and a two-stage air replenishment link can be formed to achieve phased regulation of the pressure of the air replenishment source. Maintaining a slightly positive pressure in the primary loop 3 can keep the leakage of helium within an acceptable range and avoid contamination of the helium in the primary loop 3. The first pressure sensor can monitor whether the pressure in the primary loop 3 is at a slightly positive pressure.

[0042] Alternatively, a priority switching logic based on pressure thresholds can be added on the basis of existing multiple helium storage tanks. When the main air replenishment source (helium purification system 1) cannot maintain a slightly positive pressure, the controller activates the air replenishment links of different storage tanks in sequence according to the preset storage tank priority order (for example, the main helium storage tank 7 → the second helium storage tank → the third helium storage tank), rather than relying only on the main helium storage tank 7. At the same time, through the segmented adjustment of the second regulating valve 6 and the linkage control of the isolation valve, the smooth switching of the air replenishment source can be realized. The system redundancy and fault tolerance can be improved, and the situation that a single storage tank (such as the main helium storage tank 7) has its pressure quickly exhausted due to continuous use can be avoided. The coordinated air replenishment of multiple storage tanks can extend the duration for the system to autonomously maintain a slightly positive pressure, especially suitable for scenarios with extremely long maintenance cycles, and reduce the frequency of closed-loop pressurization operations.

[0043] Furthermore, the built-in algorithm of the controller can be utilized to predict the pressure drop rate of the primary loop 3 by combining the historical data and real-time trend of the first pressure sensor, and adjust the opening degrees of the first regulating valve 4 and the second regulating valve 6 in advance. For example, when it is monitored that the pressure drop speed accelerates, the controller actively increases the opening degree of the outlet regulating valve of the helium purification system 1, or preset the initial opening degree of the regulating valve when switching to the main helium storage tank 7 for air replenishment, so as to avoid air replenishment lag. The amplitude of pressure fluctuation can be significantly reduced, and a more stable slightly positive pressure can be maintained. Through predictive regulation, the need for manual intervention is reduced, and at the same time, the risks of pressure overshoot or leakage caused by the response delay of the regulating valve are avoided, further improving the helium utilization rate.

[0044] In addition, a micro buffer chamber can be added to the first pipeline 2 at the outlet of the helium purification system 1 (transformed using the existing pipeline space), and porous materials are filled inside to form air flow damping. When replenishing air through the first regulating valve 4, the buffer chamber can absorb instantaneous pressure fluctuations, smooth the helium delivery rate, and reduce the dependence on the sealing performance of the regulating valve. It can effectively suppress the high-frequency pressure oscillation during the air replenishment process and reduce the mechanical wear caused by frequent regulation of the regulating valve. Without adding new independent devices, the system stability can be improved only by optimizing the pipeline structure, which is especially suitable for the refined control during the air replenishment stage of the helium purification system 1.

[0045] In an optional implementation manner, the helium storage tank includes:

[0046] The main helium storage tank 7 and other helium storage tanks 8 other than the main helium storage tank 7. The main helium storage tank 7 is connected to the helium purification system 1 through the second pipeline 5, and the other helium storage tanks 8 are connected to the main helium storage tank 7 through the third pipeline 9. The main helium storage tank 7 can be used as the main air replenishment source, and the other helium storage tanks 8 replenish air to the main helium storage tank 7, and the main helium storage tank 7 can further replenish air to the helium purification system 1.

[0047] In an optional implementation manner, the main helium storage tank 7 is the smallest helium storage tank, and a second pressure sensor is arranged inside the main helium storage tank 7, which is suitable for real-time monitoring of the second air pressure inside the main helium storage tank 7. The second pressure sensor can monitor whether the air pressure inside the main helium storage tank 7 is greater than the slightly positive pressure, so that helium can be smoothly replenished into the primary loop 3. The main helium storage tank 7 being the smallest helium storage tank can facilitate the control of the main helium storage tank 7 to replenish air into the helium purification system 1.

[0048] Alternatively, based on the second pressure sensor of the existing main helium storage tank 7, a third pressure sensor and a regulating valve can be added at the inlet of the third pipeline 9 of other helium storage tanks 8 and linked to the controller. When the second air pressure of the main helium storage tank 7 approaches the slightly positive pressure threshold, the third pressure sensor monitors the air replenishment pressure of other helium storage tanks 8 in real time, and the controller automatically adjusts the opening of the regulating valve to ensure that the main helium storage tank 7 is always at the required value. Through multi-level redundant pressure monitoring, the interruption of air replenishment or pressure out-of-control caused by a single sensor failure can be avoided. This mechanism can improve the reliability of the air replenishment link, especially when the main storage tank is frequently pressurized, ensure the stability of the closed-loop dynamic replenishment process, and reduce the risk of helium purity contamination.

[0049] In an alternative embodiment, a first isolation valve 10 is provided on the third pipeline 9. It can facilitate the direct air replenishment of the main helium storage tank 7 to the helium purification system 1 without being interfered by other helium storage tanks 8.

[0050] In an alternative embodiment, the first pipeline 2 is connected to the other helium storage tanks 8 through a fourth pipeline 11. The connection point of the first pipeline 2 and the fourth pipeline 11 is located at one end of the first regulating valve 4 away from the helium purification system 1, and a second isolation valve 12 is provided on the fourth pipeline 11.

[0051] In an alternative embodiment, a membrane compressor 13 is provided on the fourth pipeline 11, and the membrane compressor 13 is arranged between the second isolation valve 12 and the other helium storage tanks 8. The membrane compressor 13 can pump some of the original helium gas in the helium purification system 1 and the main helium storage tank 7 into the other helium storage tanks 8 to reduce the original air pressure in the helium purification system 1 and the main helium storage tank 7.

[0052] Alternatively, a regulating valve can be added at the front end of the membrane compressor 13 of the fourth pipeline 11 to adjust the output of the membrane compressor 13 in stages according to the change of the second air pressure of the main helium storage tank 7. For example, when the pressure of the main storage tank needs to be quickly reduced, the regulating valve keeps a large opening to increase the output of the membrane compressor 13; when the pressure approaches the target value, the regulating valve gradually reduces the opening to reduce the output of the membrane compressor 13 for fine control. The pressure impact during the helium transfer process can be reduced, and the system oscillation caused by the membrane compressor 13 can be avoided. The segmented speed regulation can extend the service life of the membrane compressor 13, reduce energy consumption at the same time, and improve the helium recovery efficiency, especially suitable for the continuous air replenishment demand in the long-term maintenance scenario.

[0053] In an alternative embodiment, a third isolation valve 14 is provided on the second pipeline 5, and the third isolation valve 14 is located between the second regulating valve 6 and the main helium storage tank 7. It can isolate the helium purification system 1 and the main helium storage tank 7.

[0054] In an alternative embodiment, a fourth isolation valve 15 is provided on the first pipeline 2, and the fourth isolation valve 15 is located between the fourth pipeline 11 and the primary circuit 3. The primary circuit 3 can be isolated from the film laminating machine and the helium purification system 1 respectively.

[0055] In an alternative embodiment, the first regulating valve 4, the second regulating valve 6, the first isolation valve 10, the second isolation valve 12, the third isolation valve 14 and the fourth isolation valve 15 are all electric valves. It is convenient to automatically control the opening degrees of the first regulating valve 4 and the second regulating valve 6, as well as the opening and closing of the first isolation valve 10, the second isolation valve 12, the third isolation valve 14 and the fourth isolation valve 15.

[0056] It should be noted that the outlet of the primary circuit 3 can be communicated with the inlet end of the helium purification system 1 through a fifth pipeline, and a fifth isolation valve is provided on the fifth pipeline, so that the helium in the primary circuit 3 can be purified by the helium purification system 1 during daily work. However, in this application, the fifth isolation valve can always remain closed.

[0057] Embodiment 2

[0058] As shown in the appendix Figure 2 The present invention also provides a method for maintaining a slightly positive pressure in the primary circuit of a high-temperature gas-cooled reactor, which is applicable to the device for maintaining a slightly positive pressure in the primary circuit of a high-temperature gas-cooled reactor as described above, and includes the following steps:

[0059] S1, close the first isolation valve 10 and the fourth isolation valve 15 to isolate the helium purification system 1 from the reactor. Since the slightly positive pressure requires a relatively small continuous gas replenishment volume, in order to reduce the impact of a large-capacity high-pressure helium gas on the maintenance of the slightly positive pressure, the main helium storage tank 7 is also isolated from other helium storage tanks 8. Open the first regulating valve 4, the second regulating valve 6, the second isolation valve 12, the third isolation valve 14 and the membrane press 13 so that the second air pressure is higher than the slightly positive pressure. Among them, there is a certain amount of high-pressure helium gas in the main helium storage tank 7 and the helium purification system 1. Start the membrane press 13 to transfer the high-pressure helium gas in the main helium storage tank 7 and the helium purification system 1 to other helium storage tanks 8, and finally reduce the overall pressure of the main helium storage tank 7 and the helium purification system 1 to the required value. The required value can be higher than the slightly positive pressure and lower than the original air pressure value, so as to be able to control the main helium storage tank 7 and the helium purification system 1 to slowly replenish gas to the primary circuit 3 and avoid impacting the maintenance of the slightly positive pressure.

[0060] S2. Close the second regulating valve 6, the second isolation valve 12, the third isolation valve 14, and the membrane compressor 13, open the fourth isolation valve 15, and adjust the opening degree of the first regulating valve 4 so that the first air pressure is slightly positive pressure; it can be realized that the primary loop 3 is supplemented with gas separately through the helium purification system 1. The opening degree of the first regulating valve 4 can be slowly adjusted to make the pressure of the primary loop 3 stable in the slightly positive pressure state, avoiding the impact on the maintenance operation surface caused by sudden pressure rise. It should be noted that step S2 can be started when the first air pressure is lower than the slightly positive pressure. An alarm threshold can be set. When the air pressure monitored by the first pressure sensor is lower than the alarm threshold, it means that the slightly positive pressure state cannot be maintained. The first pressure sensor can be a pressure monitoring instrument for the primary loop 3.

[0061] S3. If the first air pressure cannot maintain the slightly positive pressure (generally, it can be considered that the first air pressure is lower than the slightly positive pressure) when the opening degree of the first regulating valve 4 is adjusted to the maximum, then open the third isolation valve 14 and adjust the opening degree of the second regulating valve 6 so that the first air pressure is maintained at the slightly positive pressure; the primary loop 3 can be indirectly supplemented with gas through the main helium storage tank 7. The opening degree of the second regulating valve 6 can be slowly adjusted, and by coordinating with the adjustment of the opening degree of the first regulating valve 4, the pressure of the primary loop 3 can be restored to the slightly positive pressure state at a controllable rate.

[0062] S4. If the first air pressure cannot maintain the slightly positive pressure when the opening degree of the second regulating valve 6 is adjusted to the maximum, first close the second regulating valve 6 and the third isolation valve 14, open the first isolation valve 10 to make the second air pressure higher than the slightly positive pressure, so that the second air pressure can be restored to the required value to form a closed-loop supply to ensure the dynamic stability of the pressure of the primary loop 3. Then close the first isolation valve 10, open the third isolation valve 14, and adjust the opening degree of the second regulating valve 6 so that the first air pressure is the slightly positive pressure. Among them, after the second air pressure is restored to the required value, steps S3 and S4 can be repeated to make the pressure of the primary loop 3 dynamically stable. The ability to realize an infinite cycle of the gas supply process significantly improves the reliability of the entire gas supply system to cope with an extremely long maintenance cycle.

[0063] In this application, the primary loop 3 can be first supplemented with gas by the helium in the helium purification system 1. If the helium purification system 1 cannot maintain the slightly positive pressure state of the primary loop 3, the helium purification system 1 is supplemented with gas through the main helium storage tank 7. If the main helium storage tank 7 also cannot maintain the slightly positive pressure state of the primary loop 3, the main helium storage tank 7 is first supplemented with gas by other helium storage tanks 8, and then the helium purification system 1 is supplemented with gas through the main helium storage tank 7 so that the primary loop 3 maintains the slightly positive pressure state. The slightly positive pressure state of the primary loop 3 can be maintained in stages.

[0064] This application realizes the refined control of pressure input through a staged regulation strategy (first using the helium purification system 1 to supplement gas, and then switching to the main helium storage tank 7 to supplement gas).

[0065] This application has a dynamic closed-loop pressure replenishment mechanism: when the pressure of the main helium storage tank 7 is insufficient, other helium storage tanks 8 are used to dynamically pressurize the main helium storage tank 7 to form a closed-loop replenishment link, ensuring that the pressure of the air replenishment source continuously meets the requirements and avoiding the decrease in helium purity caused by the infiltration of external air due to pressure imbalance.

[0066] This application has staged valve adjustment operation and boost rate control: during the air replenishment process, by adjusting the opening degrees of the first regulating valve 4 and the second regulating valve 6 in stages, the boost rate of the primary circuit 3 is precisely controlled, effectively suppressing the pressure fluctuations that may be caused by the possible insufficient sealing performance of the regulating valve and reducing the safety risks of equipment and personnel.

[0067] This application is completely based on the original helium purification system 1 and helium supply and storage equipment of the high-temperature gas-cooled reactor. Among them, the helium supply and storage equipment includes helium storage tanks, membrane compressors 13, and related pipelines and valve bodies, without the need to additionally install devices or modify the system, significantly reducing the implementation cost. At the same time, it avoids the operation and maintenance complexity caused by equipment redundancy and realizes the efficient integration and utilization of resources;

[0068] This application innovatively regulates the air replenishment source pressure in stages (prioritizing the use of the helium purification system 1 and then switching to the helium storage tank), and combines staged valve adjustment operation to effectively solve the pressure fluctuation problem caused by the insufficient sealing performance of the regulating valve. This strategy can effectively control the boost rate, avoid the potential risks caused by sudden pressure increase to equipment and personnel, and at the same time greatly reduce the helium leakage risk.

[0069] When the pressure of the air replenishment source is insufficient, other helium storage tanks 8 are used to dynamically pressurize the main helium storage tank 7 to form a closed-loop pressure replenishment mechanism, which not only maintains the continuous availability of the air replenishment source but also avoids the consequence of affecting the helium purity of the primary circuit 3 due to pressure imbalance, significantly improving the stability and reliability of the system under long-term maintenance conditions.

[0070] The technical solution of this application has been successfully implemented to ensure the helium control of the primary circuit 3 of the high-temperature gas-cooled reactor in a slightly positive pressure state, filling a gap in the industry.

[0071] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A device for maintaining a slight positive pressure in a primary circuit of a high temperature gas-cooled reactor, characterized in that: include: A helium purification system (1), wherein an outlet end of the helium purification system (1) is connected to a primary circuit (3) via a first pipeline (2), and a first regulating valve (4) is provided on the first pipeline (2); A plurality of helium storage tanks are connected to the inlet end of the helium purification system (1) via a second pipeline (5), and a second regulating valve (6) is provided on the second pipeline (5); A first pressure sensor is arranged in the first circuit (3), which is suitable for real-time monitoring of the first air pressure in the first circuit (3).

2. The device for maintaining a slight positive pressure in a primary circuit of a high temperature gas-cooled reactor according to claim 1, characterized in that: The helium storage tank comprises: A main helium storage tank (7) and other helium storage tanks (8) other than the main helium storage tank (7), wherein the main helium storage tank (7) is connected to the helium purification system (1) via a second pipeline (5), and the other helium storage tanks (8) are connected to the main helium storage tank (7) via a third pipeline (9).

3. The device for maintaining a slight positive pressure in a primary circuit of a high temperature gas-cooled reactor according to claim 2, characterized in that: The main helium storage tank (7) is the smallest helium storage tank, and a second pressure sensor is arranged inside the main helium storage tank (7), which is suitable for real-time monitoring of the second gas pressure inside the main helium storage tank (7).

4. The device for maintaining a slight positive pressure in a primary circuit of a high temperature gas-cooled reactor according to claim 2, characterized in that: The third pipeline (9) is provided with a first isolation valve (10).

5. The device for maintaining a slight positive pressure in a primary circuit of a high temperature gas-cooled reactor according to claim 4, characterized in that: The first pipeline (2) is connected to the other helium storage tank (8) through a fourth pipeline (11); the connection between the first pipeline (2) and the fourth pipeline (11) is located at an end of the first regulating valve (4) away from the helium purification system (1), and a second isolation valve (12) is provided on the fourth pipeline (11).

6. The device for maintaining a slight positive pressure in a primary circuit of a high temperature gas-cooled reactor according to claim 5, characterized in that: A membrane press (13) is provided on the fourth pipeline (11), and the membrane press (13) is arranged between the second isolation valve (12) and other helium storage tanks (8).

7. The device for maintaining a slight positive pressure in a primary circuit of a high temperature gas-cooled reactor according to claim 5, characterized in that: The second pipeline (5) is provided with a third isolation valve (14), and the third isolation valve (14) is located between the second regulating valve (6) and the main helium storage tank (7).

8. The device for maintaining a slight positive pressure in a primary circuit of a high temperature gas-cooled reactor according to claim 7, characterized in that: A fourth isolation valve (15) is provided on the first pipeline (2), and the fourth isolation valve (15) is located between the fourth pipeline (11) and the primary circuit (3).

9. The device for maintaining a slight positive pressure in the primary circuit of a high temperature gas-cooled reactor according to claim 8, characterized in that: The first regulating valve (4), the second regulating valve (6), the first isolating valve (10), the second isolating valve (12), the third isolating valve (14) and the fourth isolating valve (15) are all electric valves.

10. A method for maintaining a slight positive pressure in a primary circuit of a high temperature gas-cooled reactor, applicable to a device for maintaining a slight positive pressure in a primary circuit of a high temperature gas-cooled reactor as claimed in any one of claims 1 to 9, characterized in that: The following steps are involved: S1, close the first isolation valve (10) and the fourth isolation valve (15), open the first regulating valve (4), the second regulating valve (6), the second isolation valve (12), the third isolation valve (14) and the membrane press (13), so that the second air pressure is higher than the slight positive pressure; S2, close the second regulating valve (6), the second isolation valve (12), and the third isolation valve (14) 、 The first regulating valve (4) and the membrane press (13) open the fourth isolation valve (15) and adjust the opening of the first regulating valve (4) so ​​that the first air pressure maintains a slightly positive pressure; S3, if the first air pressure cannot maintain a slight positive pressure when the opening of the first regulating valve (4) is adjusted to the maximum, the third isolation valve (14) is opened and the opening of the second regulating valve (6) is adjusted so that the first air pressure continues to maintain a slight positive pressure; S4, if the first air pressure cannot maintain a slightly positive pressure when the opening of the second regulating valve (6) is adjusted to the maximum, the second regulating valve (6) and the third isolation valve (14) are first closed, and the first isolation valve (10) is opened, so that the second air pressure is higher than the slightly positive pressure, and then the first isolation valve (10) is closed, the third isolation valve (14) is opened, and the opening of the second regulating valve (6) is adjusted so that the first air pressure is a slightly positive pressure.

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