Pressure control system and method of pressure vessel bearing cooling system

Abstract

The invention relates to the technical field of pressure control, in particular to a pressure control system and method of a pressure vessel bearing cooling system. Comprising a low-temperature adsorber which is internally provided with a liquid nitrogen coolant; the gas storage tank is communicated with the low-temperature adsorber, and a first valve body is arranged between the gas storage tank and the low-temperature adsorber; the gas storage tank is communicated with the pressure vessel supporting and cooling system, and a second valve body is arranged between the gas storage tank and the pressure vessel supporting and cooling system. In the invention, the low-temperature adsorber can be used for removing radioactive inert gas contained in helium in the helium purification system of the high-temperature gas cooled reactor, and the low-temperature adsorber is cooled by liquid nitrogen in order to keep the low-temperature working environment of the low-temperature adsorber. The liquid nitrogen becomes nitrogen after absorbing heat and can be communicated to a gas storage tank for storage.

Description

Technical Field

[0001] The present invention relates to the technical field of pressure control, and in particular to a pressure control system and method for a pressure vessel support cooling system. Background Art

[0002] High-temperature gas-cooled reactors are equipped with a passive pressure vessel support cooling system to cool the pressure vessel's load-bearing supports. To ensure the system's reliable heat removal capability, it must maintain a certain operating pressure.

[0003] Currently, high-temperature gas-cooled reactors (HTGRs) use separate nitrogen cylinders to replenish nitrogen to the pressure vessel support cooling system to maintain operating pressure. However, this approach requires separate nitrogen cylinders, and the procurement, transportation, and replacement of these cylinders within and outside the control area all increase the operational burden of the power plant. During nitrogen cylinder replacement, if the pressure vessel support cooling system experiences an emergency depressurization, the system may be unable to replenish and maintain pressure, compromising its cooling function. Summary of the Invention

[0004] In view of this, the present invention provides a pressure control system and method for a pressure vessel support cooling system to solve the problem in the prior art that a separate nitrogen cylinder needs to be provided, thereby increasing the operating burden of the power plant.

[0005] In a first aspect, the present invention provides a pressure control system for a pressure vessel support cooling system, comprising:

[0006] A cryogenic adsorber with liquid nitrogen coolant inside;

[0007] a gas storage tank, connected to the low-temperature adsorber, with a first valve body provided between the gas storage tank and the low-temperature adsorber;

[0008] The gas storage tank is communicated with the pressure vessel support cooling system, and a second valve body is provided between the gas storage tank and the pressure vessel support cooling system.

[0009] In the present invention, a cryogenic adsorber can be used to remove radioactive inert gases contained in helium in a high-temperature gas-cooled reactor helium purification system. In order to maintain a low-temperature working environment for the cryogenic adsorber, it is cooled by liquid nitrogen. After absorbing heat, the liquid nitrogen becomes nitrogen and can be connected to a gas storage tank for storage. When the air pressure in the pressure vessel support cooling system decreases, air can be replenished through the gas storage tank so that the specified operating air pressure is maintained in the pressure vessel support cooling system. This avoids the need to set up a separate nitrogen cylinder, reducing the operating burden of the power plant. The first valve body can isolate and connect the cryogenic adsorber and the gas storage tank, and the second valve body can isolate and connect the gas storage tank and the pressure vessel support cooling system.

[0010] In an optional embodiment, the method further includes:

[0011] a first pressure sensor, disposed in the gas storage tank, adapted to detect the gas pressure in the gas storage tank in real time;

[0012] The first control switch is electrically connected to the first valve body and the first pressure sensor respectively.

[0013] In the present invention, the first control switch can open and close the first valve body according to the air pressure in the air storage tank detected in real time by the first pressure sensor.

[0014] In an optional embodiment, the method further includes:

[0015] a second pressure sensor, disposed in the pressure vessel support cooling system, adapted to detect the air pressure of the pressure vessel support cooling system in real time;

[0016] The second control switch is electrically connected to the second valve body and the second pressure sensor respectively.

[0017] In the present invention, the second control switch can open and close the second valve body according to the air pressure in the pressure vessel support cooling system detected in real time by the second pressure sensor.

[0018] In an optional embodiment, the method further includes:

[0019] a compressor, communicatively disposed between the gas storage tank and the cryogenic adsorber, and electrically connected to the first control switch;

[0020] The compressor is suitable for transporting the gas in the low-temperature adsorber to the gas storage tank.

[0021] In the present invention, the compressor can pressurize the nitrogen in the low-temperature adsorber and send it to the gas storage tank.

[0022] In an optional embodiment, the first valve body is disposed between the low-temperature adsorber and the compressor, and can control the discharge of nitrogen in the low-temperature adsorber to the inlet of the compressor.

[0023] In an optional embodiment, the method further includes:

[0024] A pressure reducing valve is connected between the gas storage tank and the pressure vessel support cooling system;

[0025] The pressure reducing valve is suitable for delivering the gas in the gas storage tank to the pressure vessel support cooling system.

[0026] In the present invention, the pressure reducing valve can reduce the pressure of nitrogen in the gas storage tank and send it to the pressure vessel support cooling system.

[0027] In an optional embodiment, the second valve body is disposed between the gas storage tank and the pressure reducing valve, and can control the nitrogen in the gas storage tank to be discharged to the inlet of the pressure reducing valve.

[0028] In an optional embodiment, the method further includes:

[0029] an exhaust valve, connected to the low-temperature adsorber, wherein the low-temperature adsorber is adapted to discharge internal gas to the atmosphere through the exhaust valve;

[0030] The exhaust valve is electrically connected to the first control switch.

[0031] In a second aspect, the present invention further provides a pressure control method for a pressure vessel support cooling system, which is applicable to the pressure control system for a pressure vessel support cooling system as described above, and comprises:

[0032] S1: When the pressure in the gas storage tank is not higher than the first pressure, the exhaust valve is controlled to close, and the compressor and the first valve body are controlled to open until the pressure in the gas storage tank reaches the second pressure;

[0033] S2: When the pressure in the pressure vessel support cooling system is not higher than the third pressure, the second valve body is controlled to open until the pressure in the pressure vessel support cooling system reaches a fourth pressure.

[0034] In an optional embodiment, in step S1, the second control switch controls the second valve body to close.

[0035] In the present invention, the nitrogen generated by the low-temperature adsorber is fully utilized. When the air pressure in the air storage tank is low, the air storage tank is first replenished with air, and then the pressure vessel support cooling system is replenished with air through the air storage tank, so that the pressure vessel support cooling system can maintain a certain operating air pressure. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0037] Figure 1 This is a schematic structural diagram of an embodiment of the present invention;

[0038] Figure 2 Schematic diagram of the principle of an embodiment of the present invention.

[0039] Description of reference numerals:

[0040] 1. Cryogenic adsorber; 2. Gas storage tank; 3. First valve body; 4. Second valve body; 5. First control switch; 6. Second control switch; 7. Compressor; 8. Pressure reducing valve; 9. Exhaust valve; 10. Expansion tank. DETAILED DESCRIPTION

[0041] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0042] The following combination Figures 1 to 2 , describing embodiments of the present invention.

[0043] Example 1

[0044] The present invention provides a pressure control system for a pressure vessel support cooling system, such as Figure 1 Shown, including:

[0045] The cryogenic adsorber 1 is provided with liquid nitrogen coolant inside; wherein, the cryogenic adsorber 1 is part of the helium purification system of the high-temperature gas-cooled reactor. Therefore, the present invention is based on the existing system facilities and does not require the separate installation of the cryogenic adsorber 1, thereby reducing the operating burden of the power plant.

[0046] a gas storage tank 2 connected to the cryogenic adsorber 1, with a first valve body 3 provided between the gas storage tank 2 and the cryogenic adsorber 1;

[0047] The gas storage tank 2 is in communication with the pressure vessel support cooling system, with a second valve body 4 disposed between the two. The gas storage tank 2, cryogenic adsorber 1, and pressure vessel support cooling system are connected via pipelines, with the first valve body 3, second valve body 4, compressor 7, and pressure reducing valve 8 disposed on corresponding pipelines. The pressure vessel support cooling system is equipped with an expansion water tank 10, and the pressure reducing valve 8 or second valve body 4 is connected to the pressure vessel support cooling system, effectively being connected to the expansion water tank 10.

[0048] In the present invention, the cryogenic adsorber 1 can be used to remove radioactive inert gases contained in the helium in the helium purification system of the high-temperature gas-cooled reactor. In order to maintain the low-temperature working environment of the cryogenic adsorber 1, it is cooled by liquid nitrogen. After absorbing heat, the liquid nitrogen becomes nitrogen and can be connected to the gas storage tank 2 for storage. When the air pressure in the pressure vessel support cooling system decreases, air can be replenished through the gas storage tank 2 so that the specified operating air pressure is maintained in the pressure vessel support cooling system. The need to set up a separate nitrogen cylinder is avoided, reducing the operating burden of the power plant. The first valve body 3 can isolate and connect the cryogenic adsorber 1 and the gas storage tank 2, and the second valve body 4 can isolate and connect the gas storage tank 2 and the pressure vessel support cooling system.

[0049] Furthermore, the present invention fully utilizes the nitrogen generated within the high-temperature gas-cooled reactor's helium purification system, storing it for use in replenishing the pressure vessel support cooling system. This reduces operating costs, such as purchasing nitrogen cylinders, transporting them within and outside the control area, and replacing them, thereby lowering the power plant's operational burden. The provision of gas storage tank 2 ensures sufficient nitrogen storage for the pressure vessel support cooling system, improving its operational reliability.

[0050] Alternatively, a pre-cooling module can be added to the pipeline between gas storage tank 2 and compressor 7 to pre-cool the nitrogen entering compressor 7 through the liquid nitrogen circulation pipeline. The first valve body 3 is linked to the pre-cooling module. When compressor 7 starts, the pre-cooling module opens simultaneously, lowering the nitrogen temperature before pressurizing and storing it. The pre-cooling module lowers the nitrogen temperature, reduces the power consumption of compressor 7, and improves pressurization efficiency. Low-temperature nitrogen has a higher storage density, improves the capacity utilization of gas storage tank 2, and reduces the frequency of gas replenishment. This reduces overall system energy consumption and further optimizes operating costs.

[0051] Alternatively, the second valve body 4 can be replaced with a multi-stage pressure control valve assembly, comprising high-, medium-, and low-pressure solenoid valves connected in parallel. The pressure switch activates the various solenoid valves in stages based on the actual pressure of the pressure vessel support cooling system (0.15-0.45 MPa.g), dynamically adjusting the air supply flow rate via the pressure reducing valve 8. This multi-stage valve assembly enables precise control of the air supply flow rate, preventing pressure fluctuations; reduces the load on the pressure reducing valve 8, extending equipment life; and improves system pressure stability, enhancing the reliability of the support cooling function.

[0052] Alternatively, a buffer pressure-stabilizing tank can be installed between the outlet of gas storage tank 2 and second valve body 4, with a pressure sensor inside the tank linked to a solenoid valve. When the pressure vessel-supported cooling system requires air replenishment, the buffer tank prioritizes releasing the stored 0.5 MPa nitrogen. If insufficient, gas is supplied directly from gas storage tank 2. The buffer tank mitigates the instantaneous pressure surge of the replenishment, protecting pressure reducing valve 8 and the piping. Small pressure fluctuations are automatically balanced by the buffer tank, reducing the number of times the main gas storage tank 2 is opened and closed. This accelerates system response and improves the smoothness of the replenishment process.

[0053] In an optional embodiment, the method further includes:

[0054] A first pressure sensor is provided in the gas storage tank 2 and is suitable for detecting the air pressure in the gas storage tank 2 in real time;

[0055] The first control switch 5 is electrically connected to the first valve body 3 and the first pressure sensor respectively.

[0056] In the present invention, the first control switch 5 can open and close the first valve body 3 according to the air pressure in the air storage tank 2 detected in real time by the first pressure sensor.

[0057] In an optional embodiment, the method further includes:

[0058] a second pressure sensor, disposed in the pressure vessel support cooling system, adapted to detect the air pressure of the pressure vessel support cooling system in real time;

[0059] The second control switch 6 is electrically connected to the second valve body 4 and the second pressure sensor respectively.

[0060] In the present invention, the second control switch 6 can open and close the second valve body 4 according to the air pressure in the pressure vessel support cooling system detected in real time by the second pressure sensor.

[0061] The first valve body 3 and the second valve body 4 in the present invention may both be solenoid valves.

[0062] In an optional embodiment, the method further includes:

[0063] a compressor 7, which is communicatively arranged between the gas storage tank 2 and the cryogenic adsorber 1 and is electrically connected to the first control switch 5;

[0064] The compressor 7 is suitable for transporting the gas in the low-temperature adsorber 1 to the gas storage tank 2 .

[0065] In the present invention, the compressor 7 can pressurize the nitrogen in the cryogenic adsorber 1 and send it to the gas storage tank 2 .

[0066] In an optional embodiment, the first valve body 3 is disposed between the low-temperature adsorber 1 and the compressor 7 to control the nitrogen in the low-temperature adsorber 1 to be discharged to the inlet of the compressor 7 .

[0067] Alternatively, a heat exchange module can be added to the outlet piping of compressor 7 and coupled to the liquid nitrogen coolant circulation piping of cryogenic adsorber 1. The heat exchange module utilizes the exhaust heat of compressor 7 to preheat the liquid nitrogen, reducing the liquid nitrogen consumption of cryogenic adsorber 1 while simultaneously delivering the cooled nitrogen to gas storage tank 2. Recovering the waste heat of compressor 7 reduces liquid nitrogen coolant consumption, improving energy efficiency by 10% to 15%. Preheating the liquid nitrogen also shortens the cooling startup time of cryogenic adsorber 1, optimizing the overall energy efficiency of the system and further reducing operating costs.

[0068] Alternatively, the first and second control switches 5 and 6 can be replaced with an adaptive PID controller integrated between the pressure sensor and the valve body. This controller dynamically adjusts the PID parameters based on the real-time pressure change rate, optimizing the valve opening and closing response speed and linking the pressure reducing valve 8 to fine-tune the flow rate. This adaptive algorithm reduces the risk of pressure overshoot and improves control accuracy to ±0.02 MPa. This reduces frequent valve opening and closing, extending the valve's service life and enhancing system pressure stability, making it suitable for scenarios with high-frequency pressure fluctuations.

[0069] Alternatively, a gradient layered baffle made of a highly thermally conductive aluminum-silicon alloy can be installed inside gas tank 2. This layered structure guides the nitrogen flow from top to bottom, accelerating heat exchange with the tank wall while evenly discharging low-temperature nitrogen to pressure reducing valve 8 through the bottom diversion port. This layered structure improves the heat exchange efficiency of gas tank 2, reducing the nitrogen temperature by 5-8°C. It also ensures a uniform nitrogen flow rate, preventing wear on pressure reducing valve 8 caused by sudden flow changes. It also increases the effective volume utilization of gas tank 2 by 20%.

[0070] In an optional embodiment, the method further includes:

[0071] A pressure reducing valve 8 is provided between the gas storage tank 2 and the pressure vessel support cooling system;

[0072] The pressure reducing valve 8 is adapted to deliver the gas in the gas storage tank 2 to the pressure vessel support cooling system.

[0073] In the present invention, the pressure reducing valve 8 can reduce the pressure of the nitrogen in the gas storage tank 2 and send it to the pressure vessel support cooling system.

[0074] In an optional embodiment, the second valve body 4 is disposed between the gas storage tank 2 and the pressure reducing valve 8 to control the nitrogen in the gas storage tank 2 to be discharged to the inlet of the pressure reducing valve 8.

[0075] Alternatively, a dynamic pressure differential feedback adjustment module with a built-in pressure differential sensor and microprocessor can be added between the pressure reducing valve 8 and the second valve body 4. This module monitors the pressure differential between the outlet of the gas storage tank 2 and the inlet of the pressure reducing valve 8 in real time and adjusts the opening of the second valve body 4 to maintain the inlet pressure of the pressure reducing valve 8 within a preset range (e.g., 0.8-1.0 MPa), thereby optimizing the workload of the pressure reducing valve 8. Dynamic adjustment can prevent the pressure reducing valve 8 from losing regulation accuracy due to inlet pressure fluctuations, extend the service life of the pressure reducing valve 8, and reduce mechanical wear caused by sudden changes in pressure differential. It also improves system pressure control accuracy to ±0.01 MPa, making the gas replenishment process more stable.

[0076] Alternatively, a nitrogen purity monitoring device can be integrated into the outlet pipeline of the pressure reducing valve 8 to detect nitrogen purity in real time using spectral analysis technology. When it is detected that the impurity content exceeds a threshold value (e.g., ≥0.5%), the device links the second control switch 6 to close the second valve body 4, triggers an alarm, and simultaneously switches to the backup gas tank 2 or starts the compressor 7 to replenish high-purity nitrogen. Ensure that the nitrogen purity added to the pressure vessel support cooling system meets the requirements (≥99.95%); avoid impurity accumulation that affects the system's heat dissipation efficiency; and the automated switching mechanism ensures continuous system operation and reduces manual intervention.

[0077] Alternatively, the single pressure reducing valve 8 can be replaced with two sets of pressure reducing valves 8 in parallel, each with a different pressure reducing threshold (e.g., 0.5 MPa and 0.3 MPa). The outlet of the second valve body 4 is divided into two routes: the main route is directly supplied with air through the pressure reducing valve 8A, and the auxiliary route is a backup air supply through the pressure reducing valve 8B and the buffer tank. When the main pressure reducing valve 8 fails, the auxiliary route is automatically activated. The redundant design avoids the risk of single point failure and improves system reliability; the graded pressure reduction reduces the load on a single pressure reducing valve 8 and extends the life of the equipment; the buffer tank further smooths pressure fluctuations and enhances the system's fault tolerance.

[0078] Alternatively, magnetic levitation technology can be used to replace the traditional mechanical pressure reducing valve 8, creating a non-contact floating gap between the valve core and the valve body. The magnetic levitation pressure reducing valve 8 dynamically adjusts the valve core position through an electromagnetic coil, achieving frictionless and precise pressure control. The opening of the second valve body 4 is linked to the magnetic levitation valve, forming a closed-loop regulation. This eliminates mechanical friction loss, extending the device life by more than three times. The response speed is improved to milliseconds, and the pressure regulation accuracy reaches ±0.005 MPa. This reduces maintenance frequency and is suitable for high-frequency air replenishment scenarios.

[0079] In an optional embodiment, the method further includes:

[0080] an exhaust valve 9, which is in communication with the low-temperature adsorber 1, and the low-temperature adsorber 1 is adapted to discharge internal gas to the atmosphere through the exhaust valve 9;

[0081] The exhaust valve 9 is electrically connected to the first control switch 5 .

[0082] Example 2

[0083] The present invention also provides a pressure control method for a pressure vessel support cooling system, which is applicable to a pressure vessel support cooling system pressure control system as described above. Figure 2 As shown, the said includes:

[0084] S1: When the pressure in the gas storage tank 2 is not higher than the first pressure, the first control switch 5 controls the exhaust valve 9 to close and the compressor 7 and the first valve body 3 to open until the gas storage tank 2 reaches the second pressure. The first pressure can be 0.8 MPa, and the second pressure can be 1 MPa. After the gas storage tank 2 reaches the second pressure, the exhaust valve 9 can be opened by the first control switch 5, and the compressor 7 and the first valve body 3 can be closed.

[0085] In step S2, when the pressure vessel support cooling system is below the third pressure, the second control switch 6 controls the second valve body 4 to open until the pressure vessel support cooling system reaches a fourth pressure. The third pressure can be 0.2 MPa, and the fourth pressure can be 0.45 MPa. The nitrogen in the gas storage tank 2 can be reduced to 0.5 MPa after passing through the pressure reducing valve 8. When the pressure vessel support cooling system reaches the fourth pressure, the second control switch 6 controls the second valve body 4 to close.

[0086] In an optional embodiment, in step S1 , the second control switch 6 controls the second valve body 4 to close.

[0087] In the present invention, the nitrogen generated by the cryogenic adsorber 1 is fully utilized. When the air pressure in the gas tank 2 is low, the gas tank 2 is first replenished, and then the pressure vessel support cooling system is replenished through the gas tank 2, so that the pressure vessel support cooling system can maintain a certain operating air pressure. The outlet pipeline of the gas tank 2 is connected to the gas replenishment pipeline of the pressure vessel support cooling system. The pressure of the gas tank 2 and the pressure vessel support cooling system is automatically controlled through the first control switch 5, the second control switch 6, the first valve body 3, the second valve body 4, the compressor 7, and the pressure reducing valve 8.

[0088] Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention. Such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A pressure control system for a pressure vessel support cooling system, characterized in that: include: A cryogenic adsorber (1) having a liquid nitrogen coolant disposed therein; A gas storage tank (2) is connected to the low-temperature adsorber (1), and a first valve body (3) is provided between the gas storage tank (2) and the low-temperature adsorber (1); The gas storage tank (2) is in communication with a pressure vessel support cooling system, and a second valve body (4) is provided between the gas storage tank (2) and the pressure vessel support cooling system.

2. The pressure control system of the pressure vessel support cooling system according to claim 1, characterized in that: Also includes: A first pressure sensor is disposed in the gas storage tank (2) and is suitable for detecting the gas pressure in the gas storage tank (2) in real time; The first control switch (5) is electrically connected to the first valve body (3) and the first pressure sensor respectively.

3. The pressure control system of the pressure vessel support cooling system according to claim 1, characterized in that: Also includes: a second pressure sensor, disposed in the pressure vessel support cooling system, adapted to detect the air pressure of the pressure vessel support cooling system in real time; The second control switch (6) is electrically connected to the second valve body (4) and the second pressure sensor respectively.

4. The pressure control system of the pressure vessel support cooling system according to claim 2, characterized in that: Also includes: A compressor (7) is arranged in communication between the gas storage tank (2) and the low-temperature adsorber (1), and is electrically connected to the first control switch (5); The compressor (7) is suitable for transporting the gas in the low-temperature adsorber (1) to the gas storage tank (2).

5. The pressure control system of the pressure vessel support cooling system according to claim 4, characterized in that: The first valve body (3) is arranged between the low-temperature adsorber (1) and the compressor (7).

6. The pressure control system of the pressure vessel support cooling system according to claim 3, characterized in that: Also includes: a pressure reducing valve (8) communicating between the gas storage tank (2) and the pressure vessel support cooling system; The pressure reducing valve (8) is suitable for delivering the gas in the gas storage tank (2) to the pressure vessel support cooling system.

7. The pressure control system of the pressure vessel support cooling system according to claim 6, characterized in that: The second valve body (4) is arranged between the gas storage tank (2) and the pressure reducing valve (8).

8. The pressure control system of the pressure vessel support cooling system according to claim 2, characterized in that: Also includes: an exhaust valve (9) in communication with the low-temperature adsorber (1), wherein the low-temperature adsorber (1) is adapted to discharge internal gas to the atmosphere through the exhaust valve (9); The exhaust valve (9) is electrically connected to the first control switch (5).

9. A pressure control method for a pressure vessel support cooling system, applicable to a pressure vessel support cooling system pressure control system according to any one of claims 1 to 8, characterized in that: Said include: S1, when the air pressure in the air storage tank (2) is not higher than the first air pressure, the exhaust valve (9) is controlled to close, and the compressor (7) and the first valve body (3) are controlled to open until the air pressure in the air storage tank (2) reaches the second air pressure; S2, when the pressure in the pressure vessel support cooling system is not higher than the third pressure, the second valve body (4) is controlled to open until the pressure in the pressure vessel support cooling system reaches the fourth pressure.

10. The pressure control method of the pressure vessel support cooling system according to claim 9, characterized in that: In step S1, the second control switch (6) controls the second valve body (4) to close.

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