Method for relieving large-range damage of passive pressurized water reactor nuclear power plant
By re-establishing the command and control system and implementing mitigation measures when a large-scale damage occurs in non-active pressurized water reactor nuclear power plants, the problem of the failure of the cooling system of the nuclear power plants after damage is solved, and the safe, stable and controllable state of the nuclear power plants are restored.
Patent Information
- Application Number
- CN202411640539.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-18
- Publication Date
- 2025-03-04
AI Technical Summary
The prior art is difficult to effectively deal with the loss of command and control system and the failure of cooling systems in the event of large-scale damage in non-active pressurized water reactor nuclear power plants, especially when the main control room and long-distance shutdown room cannot operate.
Provide a mitigation method, including determining whether the emergency response organization is in place when the main control room and long-distance shutdown room of the nuclear power plant cannot operate, and performing initial response guidelines before it is in place. After the emergency response organization is in place, implement a long-term mitigation process for large-scale damage mitigation guidelines, including restoring power, controlling reactor coolant systems, hydrating spent fuel pools and containment, and conducting long-term monitoring.
By re-establishing the command and control system of the nuclear power plant and implementing mitigation measures with diversified drive systems in-site cabinets, the recovery operation of the cooling system can be simplified, the required equipment and resources can be reduced, and the threat to the nuclear power plant can be timely alleviated, ensuring that the core, containment and spent fuel pools can be safe, stable and controllable.
Smart Images
Figure CN119560201A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of nuclear power plants, and in particular to a method for alleviating large-scale damage to a passive pressurized water reactor nuclear power plant. Background Art
[0002] A nuclear power plant includes a large number of nuclear facilities. If a fire or other accident occurs in a nuclear power plant, it may cause serious consequences such as the release of radioactive fission products. The existing technology has given clear requirements for nuclear power plants to deal with threats beyond the design basis, that is, when a nuclear power plant suffers extensive damage, the nuclear power plant must use all available resources to ensure or restore the cooling of the core, containment and spent fuel pool. At the same time, the concept of extensive damage mitigation guidelines is also proposed. When a nuclear power plant suffers extensive damage due to a fire, explosion or other accident, the command and control system of the nuclear power plant is rebuilt, and all resources are used to ensure or restore the cooling of the core, containment and spent fuel pool.
[0003] At present, the existing procedures and guidelines (such as emergency operation procedures, severe accident management guidelines, etc.) of nuclear power plants at home and abroad are mainly symptom-oriented. When a nuclear power plant suffers extensive damage and loses its normal command and control system, it will lose the ability to monitor the nuclear power plant and cannot mitigate nuclear power plant accidents by implementing existing guidelines. In addition, passive pressurized water reactor nuclear power plants at home and abroad have not yet been built on a large scale, and accident handling for passive pressurized water reactor nuclear power plants is still immature. Summary of the invention
[0004] In order to alleviate, mitigate or eliminate the above-mentioned technical problems, the present application provides a method for mitigating large-scale damage to passive pressurized water reactor nuclear power plants, and establishes a mitigation method for responding to large-scale damage caused by extreme external events such as explosions or fires in nuclear power plants due to human or natural extreme external events.
[0005] In a first aspect, the present application provides a method for mitigating large-scale damage in a passive pressurized water reactor nuclear power plant, comprising:
[0006] In the event that the main control room and remote shutdown room of a nuclear power plant are unable to operate or the inherent AC and DC power supplies of the nuclear power plant are lost, determine whether the emergency response organization is in place;
[0007] Before the emergency response organization is in place, implement the initial response guidelines;
[0008] After the emergency response organization is in place, implement the long-term mitigation process of the extensive damage mitigation guidelines.
[0009] In a possible implementation, the executing initial response guidelines includes:
[0010] Implement control and command reestablishment guidelines to establish command and control systems for nuclear power plants;
[0011] Follow the initial response guidance process.
[0012] In a possible implementation, the process of executing the initial response guidelines includes:
[0013] Establishing a local cabinet for a diversified drive system in a nuclear power plant, the local cabinet for a diversified drive system adopts a power supply line different from that of the main control room and the remote shutdown room, and is connected to a battery, and the local cabinet for a diversified drive system is used to perform shutdown operations and containment isolation operations, monitor target parameters of the nuclear power plant, control and monitor the status of the reactor under accidents, and monitor and control safety-related systems of the nuclear power plant;
[0014] Relying on the diversified drive system, the local cabinet executes the initial action recovery guide to confirm whether the nuclear power plant is shut down. If not, perform manual shutdown operation; if the nuclear power plant is shut down, confirm whether the target systems and equipment in the nuclear power plant are operating as designed. If the target systems and equipment are operating as designed, monitor the nuclear power plant parameters; if not, manually start the target systems and equipment to prevent secondary breaches and ensure the integrity of the reactor coolant system;
[0015] Execute the communication recovery guidelines, obtain the communication status and the reason for the failure, and restore the communication;
[0016] Implement the power plant damage assessment guidelines to obtain damage status assessment feedback for target objects within the nuclear power plant;
[0017] Execute the initial response exit guidelines and provide the emergency response organization with initial response information, which includes the status of the emergency response organization in place, whether the initial response action is completed, the nuclear power plant damage status assessment feedback and whether the target communication is unobstructed.
[0018] In a possible implementation, the long-term mitigation process of executing the large-scale damage mitigation guidelines includes:
[0019] Implement the power restoration guidelines to restore power within the nuclear power plant;
[0020] When the core outlet temperature is higher than the preset temperature, the core charge control guideline is executed to control the reactor coolant system to depressurize, and gravity injection is started to restore the reactor coolant system charge;
[0021] When the liquid level in the spent fuel pool is lower than the preset height, follow the spent fuel pool mitigation guidelines and perform spent fuel pool water replenishment and spraying operations;
[0022] In the event that the accident lasts longer than the preset time and the temperature inside the containment continues to rise, the containment water replenishment guidelines shall be implemented;
[0023] Implement long-term monitoring guidelines to monitor long-term concerns related to the implementation of long-term mitigation strategies.
[0024] In a possible implementation, controlling the reactor coolant system to depressurize and starting gravity injection includes:
[0025] Through the on-site cabinet of the diversified drive system, confirm whether the relevant valves of the automatic pressure relief system and the built-in refueling water tank are opened. If they are opened, monitor the status and change trend of relevant parameters. If they are not opened, use the on-site cabinet of the diversified drive system to open the automatic pressure relief system valves and the relevant valves of the built-in refueling water tank, control the pressure relief of the reactor coolant system, and start gravity injection.
[0026] In a possible implementation, the executing long-term monitoring guidelines further includes:
[0027] Get the current status of the nuclear power plant.
[0028] A possible implementation also includes:
[0029] Follow the on-site execution guidelines after the emergency response organization is in place to obtain the information required for accident mitigation.
[0030] A possible implementation also includes:
[0031] Based on radiation protection principles and ambient temperature, route guidance rules leading to the local cabinet room of the diversified drive system are formulated.
[0032] In a possible implementation, the target system and equipment include a passive residual heat removal system and a core water supply tank.
[0033] In a possible implementation, the damage status of the target object includes damage to key plant buildings, damage to target systems and equipment, reactor core status, containment integrity, status of important auxiliary support systems in the plant area, and availability of major water sources.
[0034] Compared with the prior art, this application has the following advantages:
[0035] The mitigation method for large-scale damage of a passive pressurized water reactor nuclear power plant provided by the present application includes judging whether the emergency response organization is in place when both the main control room and the remote shutdown room of the nuclear power plant cannot operate or the inherent AC and DC power supplies of the nuclear power plant are lost; before the emergency response organization is in place, the initial response guidelines are executed; after the emergency response organization is in place, the long-term mitigation process of the large-scale damage mitigation guidelines is executed. The present application establishes a mitigation method for responding to large-scale damage caused by human or natural extreme external events such as explosions and fires in passive pressurized water reactor nuclear power plants, re-establishes the command and control system of the nuclear power plant when the above-mentioned events and disasters occur, and uses all resources to ensure or restore the cooling of the core, containment and spent fuel pool, wherein, based on the characteristics of passive pressurized water reactor nuclear power plants, by automatically or manually starting passive mitigation measures, it is possible to simplify the operating steps required to ensure or restore the cooling of the core, containment and spent fuel pool, reduce the equipment required to implement mitigation measures, and timely alleviate the threats faced by nuclear power plants, so that nuclear power plants can eventually reach a safe, stable and controllable state. BRIEF DESCRIPTION OF THE DRAWINGS
[0036] The accompanying drawings are included to provide a further understanding of the present application. They are included and constitute a part of the present application. The accompanying drawings illustrate embodiments of the present application and together with the present specification serve to explain the principles of the present application. In the accompanying drawings:
[0037] Figure 1 It is a flow chart of a method for mitigating large-scale damage of a passive pressurized water reactor nuclear power plant provided in an embodiment of the present application;
[0038] Figure 2 It is a schematic diagram of a method for mitigating large-scale damage to a passive pressurized water reactor nuclear power plant provided in an embodiment of the present application;
[0039] Figure 3 It is a schematic diagram of an initial response guideline process provided by an embodiment of the present application;
[0040] Figure 4 It is a schematic diagram of a long-term mitigation process for executing large-scale damage mitigation guidelines provided in an embodiment of the present application. DETAILED DESCRIPTION
[0041] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of the present application. For ordinary technicians in this field, the present application can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.
[0042] As shown in this application, unless the context clearly indicates an exception, the words "a", "an", "a kind" and / or "the" do not refer to the singular, but also include the plural. Generally speaking, the terms "include" and "comprise" only indicate the inclusion of the steps and elements that have been clearly identified, and these steps and elements do not constitute an exclusive list, and the method or device may also include other steps or elements.
[0043] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values of the parts and steps set forth in these embodiments do not limit the scope of the application. Meanwhile, it should be understood that, for ease of description, the sizes of the various parts shown in the accompanying drawings are not drawn according to actual proportional relationships. The technology, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be considered as a part of the specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, and therefore, once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.
[0044] In addition, although the terms used in this application are selected from well-known and commonly used terms, some of the terms mentioned in this application specification may be selected by the applicant at his or her discretion, and their detailed meanings are explained in the relevant parts of the description of this article. In addition, it is required to understand this application not only by the actual terms used, but also by the meaning implied by each term.
[0045] Flowcharts are used in the present application to illustrate the operations performed by the system according to the embodiments of the present application. It should be understood that the preceding or following operations are not necessarily performed accurately in order. On the contrary, various steps may be processed in reverse order or simultaneously. At the same time, other operations may be added to these processes, or one or more operations may be removed from these processes.
[0046] Figure 1 Schematic diagram of a method for mitigating large-scale damage to a passive pressurized water reactor nuclear power plant provided in an embodiment of the present application. Figure 1 As shown in the figure, the mitigation methods for large-scale damage to passive PWR nuclear power plants include the following:
[0047] Step 101: When the main control room and the remote shutdown room of the nuclear power plant are unable to operate or the inherent AC and DC power supplies of the nuclear power plant are lost, determine whether the emergency response organization is in place.
[0048] The emergency response organization is the accident mitigation command center in the extensive damage mitigation guidelines. Its organizational structure, responsibilities and time of deployment are all specified in the emergency plan. There is an interface between the extensive damage mitigation guidelines and the nuclear power plant emergency plan and the regulations for the use of mobile pumps and mobile power sources in nuclear power plants.
[0049] When a nuclear power plant suffers an explosion, fire or other man-made or natural disaster that renders the main control room and remote shutdown room inoperable, or the nuclear power plant's AC and DC power supplies are lost, the wide-area damage mitigation guidelines can be directly followed without establishing a transition interface from other nuclear power plant regulations and guidelines.
[0050] Since the on-site conditions under extreme external events are relatively complex, the activation of the emergency response organization of the nuclear power plant may be affected. In the embodiment of the present application, the mitigation of extreme external events is divided into two stages: the first stage is before the emergency response organization is in place, and the second stage is after the emergency response organization is in place (including the subsequent controllable stable state). Figure 2 As shown. In the first stage, the local response team is composed of the survivors of the accident and the on-duty personnel of the non-accident crew, relying on the local cabinets of the diversified drive system to implement the initial response guidelines. In the second stage, the emergency response organization coordinates the mitigation of the entire accident and implements the long-term mitigation guidelines.
[0051] In some embodiments, based on radiation protection principles and ambient temperature, route guidance rules leading to the on-site cabinet rooms of the diversified drive systems can be formulated, accessible paths for on-site operation of equipment can be provided, and relevant personnel of the nuclear power plant can be guided to implement on-site operations.
[0052] Step 102: Before the emergency response organization is in place, execute the initial response guidelines.
[0053] The purpose of the initial response guidelines is to carry out simple mitigation work with less negative effects by relying on the local cabinets of the diversified drive system before the emergency response organization is in place. In some embodiments, step 102 includes executing the control and command reconstruction guidelines, establishing the command and control system of the nuclear power plant, and then executing the initial response guidelines process.
[0054] Please refer to Figure 3 , the initial response guidelines process includes the following:
[0055] Step 121, establish a diversified drive system on-site cabinet in the nuclear power plant, the diversified drive system on-site cabinet adopts a power supply line different from that of the main control room and the remote shutdown room, and is connected to a battery. When the power supply line is unavailable, the battery can be used to power it for a certain period of time. The diversified drive system on-site cabinet is used to perform shutdown operations and containment isolation operations, monitor nuclear power plant target parameters (such as the hot section temperature of each loop, the pressurizer water level, the steam generator water level, the core outlet temperature, etc.), and control and monitor the state of the reactor under accidents. In addition, the diversified drive system on-site cabinet is also used to monitor and control the safety-related systems of the nuclear power plant (such as the passive residual heat removal system, the core water tank, the internal refueling water tank and the gravity injection and containment recirculation related valves connected thereto, the hydrogen igniter, and the passive containment cooling system), so as to provide cooling for the core, the containment, and the spent fuel pool.
[0056] Step 122, relying on the diversified drive system, the local cabinet executes the initial action recovery guide to confirm whether the nuclear power plant is shut down. If not, perform a manual shutdown operation; if it is shut down, confirm whether the target systems and equipment in the nuclear power plant are operating as designed. If the target systems and equipment are operating as designed, monitor the nuclear power plant parameters; if they are not operating as designed, manually start the target systems and equipment to prevent secondary breaches and ensure the integrity of the reactor coolant system.
[0057] In some embodiments, the target systems and equipment include passive residual heat removal systems, core water tanks and other passive equipment. The commissioning of these equipment can cool the core, simplify the operation steps and required equipment, and do not require additional steps and equipment to inject water into the secondary side to cool the core. In actual operation, the reactor is shut down in time to confirm whether the passive residual heat removal system, core water tank and other systems and equipment are operating as designed to prevent secondary breaches and ensure the integrity of the reactor coolant system.
[0058] By operating the plant's passive systems, the equipment and resources required to restore cooling of the core, containment, and spent fuel pool are reduced, and related operational procedures are simplified, making it possible to more quickly mitigate widespread damage to passive PWR nuclear power plants using fewer resources.
[0059] Step 123: Execute the communication recovery guideline, obtain the communication status and the reason for the failure, and restore the communication.
[0060] In actual operation, the communication status and reasons for failure between the local response team leader and the emergency command center and key locations can be confirmed, and appropriate solutions can be selected to restore communication. After communication is restored, relevant personnel inside and outside the site can be notified of the progress of the accident and mitigation measures.
[0061] Step 124: Execute the power plant damage assessment guidelines to obtain damage status assessment feedback of the target objects in the nuclear power plant.
[0062] In some embodiments, assessments are conducted on damage to key nuclear power plant buildings, damage to target systems and equipment, reactor core status, containment integrity, status of important auxiliary support systems in the plant area, availability of major water sources, etc., to obtain damage status assessment feedback on these target objects, thereby providing convenience and effective guidance for the implementation of subsequent power plant mitigation measures.
[0063] Step 125, execute the initial response exit guidelines, and provide the emergency response organization with initial response information, wherein the initial response information includes the emergency response organization's position, whether the initial response action is completed, the nuclear power plant damage status assessment feedback, and whether the target communication is unobstructed.
[0064] After the completion of step 121-step 124, the emergency response organization is in place, and the initial response information such as whether the initial response action is completed, the nuclear power plant damage status assessment feedback, and whether the target communication is smooth is provided to the emergency response organization, so as to facilitate the implementation of subsequent strategies. After that, with the approval of the emergency response organization, the initial response guidelines for large-scale damage mitigation can be withdrawn.
[0065] It should be noted that, according to Figure 3 The priority levels given in the flowchart shown are to execute steps 122 to 124 in sequence, that is, to execute the initial action recovery guidelines, communication recovery guidelines and power plant damage assessment guidelines in sequence, but the priorities can also be re-ordered according to the actual status of the nuclear power plant and other relevant conditions. For example, the communication recovery guidelines, initial action recovery guidelines and power plant damage assessment guidelines can be executed in sequence, or multiple guidelines can be executed in parallel.
[0066] Step 103: After the emergency response organization is in place, execute the long-term mitigation process of the large-scale damage mitigation guidelines.
[0067] Please refer to Figure 4 , the long-term mitigation process for implementing the extensive damage mitigation guidelines includes the following:
[0068] Step 131: Execute the power restoration guidelines within the plant to restore the power within the nuclear power plant, thereby supplying power to important equipment within the nuclear power plant.
[0069] Step 132: When the core outlet temperature is higher than the preset temperature T, execute the core charge control guideline, control the reactor coolant system to depressurize, and start gravity injection and other measures to restore the reactor coolant system charge. Otherwise, execute step 133.
[0070] In some embodiments, controlling the depressurization of the reactor coolant system and starting gravity injection includes: confirming whether the relevant valves of the automatic depressurization system and the built-in refueling water tank are opened through the on-site cabinet of the diversified drive system; if they are opened, monitoring the status and change trend of relevant parameters; if they are not opened, using the on-site cabinet of the diversified drive system to open the automatic depressurization system valves and the relevant valves of the built-in refueling water tank, controlling the depressurization of the reactor coolant system, and starting gravity injection and other measures, so that the core cooling can be maintained for a longer period of time without additional water replenishment, thereby avoiding core melting and disintegration.
[0071] Step 133: When the liquid level of the spent fuel pool is lower than the preset height H, the spent fuel pool mitigation guidelines are executed to perform the spent fuel pool water replenishment and spraying operations. Otherwise, step 134 is executed.
[0072] Step 134: If the accident occurs for longer than the preset time and the temperature in the containment shell continues to rise, the containment shell water replenishment guideline is executed. Otherwise, step 135 is executed.
[0073] Step 135: Execute the long-term monitoring guidelines to monitor long-term concerns related to the implementation of the long-term mitigation strategy.
[0074] In some embodiments, the current nuclear power plant status is also obtained during the execution of the long-term monitoring guidelines, so as to prepare for the exit of the large-scale damage mitigation guidelines.
[0075] Usually, according to Figure 4 The priority levels given in the flowchart are to execute steps 131 to 134 in sequence, that is, to execute the in-plant power restoration guidelines, the core loading control guidelines, the spent fuel pool mitigation guidelines and the containment water replenishment guidelines in sequence. However, the priorities may be re-ordered according to the actual state of the nuclear power plant, the degree of parameter deviation and other relevant conditions, such as executing the in-plant power restoration guidelines, the spent fuel pool mitigation guidelines, the core loading control guidelines and the containment water replenishment guidelines in sequence, or executing multiple guidelines in parallel.
[0076] In some embodiments, after the emergency response organization is in place, the on-site execution guidelines after the emergency response organization is in place will be executed to obtain the information required for accident mitigation.
[0077] The method for mitigating large-scale damage to a passive pressurized water reactor nuclear power plant provided in the embodiment of the present application is applicable to a passive pressurized water reactor nuclear power plant to cope with large-scale damage scenarios caused by extreme external events in a passive pressurized water reactor nuclear power plant. The accident handling method provided in the above embodiment can promptly restore the control and command system, power supply, communication, etc. of the nuclear power plant, facilitate the implementation of subsequent mitigation measures, and effectively cool the core by timely stopping the reactor, removing the core decay heat, and restoring the core load, so that the core remains or recovers a stable and controllable state. At the same time, the integrity of the containment can also be guaranteed, and the decay heat can be removed through the final heat sink to keep the containment in a stable and controllable state. In addition, it can ensure that the spent fuel is submerged in water to a certain height, and the decay heat is removed in time to keep the spent fuel pool in a stable and controllable state.
[0078] The basic concepts have been described above. Obviously, for those skilled in the art, the above disclosure is only an example and does not constitute a limitation of the present application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the present application. Such modifications, improvements and amendments are suggested in the present application, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the present application.
[0079] At the same time, the present application uses specific words to describe the embodiments of the present application. For example, "one embodiment", "an embodiment", and / or "some embodiments" refer to a certain feature, structure or characteristic related to at least one embodiment of the present application. Therefore, it should be emphasized and noted that "one embodiment" or "an embodiment" or "an alternative embodiment" mentioned twice or more in different positions in this specification does not necessarily refer to the same embodiment. In addition, some features, structures or characteristics in one or more embodiments of the present application can be appropriately combined.
[0080] Generally, various embodiments of the present application may be implemented in hardware or dedicated circuits, software, logic, or any combination thereof. Certain aspects may be implemented in hardware, while other aspects may be implemented in firmware or software, which may be performed by a controller, microprocessor, or other computing device. Although various aspects of the embodiments of the present application are shown and described as block diagrams, flow charts, or using some other graphical representations, it should be understood that, as non-limiting examples, the devices, systems, techniques, or methods described herein may be implemented in hardware, software, firmware, dedicated circuits or logic, general hardware or controllers or other computing devices, or some combination thereof.
[0081] In addition, although the operations are described in a specific order, this should not be construed as requiring to perform these operations in the specific order or sequence shown, or to perform all the operations shown, to obtain the desired result. In some cases, multitasking and parallel processing may be advantageous. Similarly, although several specific implementation details are included in the above discussion, these details should not be interpreted as limiting the scope of the application, but can be interpreted as a description of the specific features of a particular embodiment. Some of the features described in the context of a separate embodiment may also be implemented in combination in a single embodiment. On the contrary, the various features described in the context of a single embodiment may also be implemented in multiple embodiments individually or in any suitable sub-combination.
[0082] Although the present application has been described with reference to the current specific embodiments, ordinary technicians in this technical field should recognize that the above embodiments are only used to illustrate the present application, and various equivalent changes or substitutions may be made without departing from the spirit of the present application. Therefore, as long as the changes and modifications to the above embodiments are within the essential spirit of the present application, they will fall within the scope of the present application.
Claims
1. A method for mitigating large-scale damage in a passive pressurized water reactor nuclear power plant, characterized in that: include: In the event that the main control room and remote shutdown room of a nuclear power plant are unable to operate or the inherent AC and DC power supplies of the nuclear power plant are lost, determine whether the emergency response organization is in place; Before the emergency response organization is in place, implement the initial response guidelines; After the emergency response organization is in place, implement the long-term mitigation process of the extensive damage mitigation guidelines.
2. The method according to claim 1, characterized in that The guidelines for implementing the initial response include: Implement control and command reestablishment guidelines to establish command and control systems for nuclear power plants; Follow the initial response guidance process.
3. The method according to claim 2, characterized in that The process of executing the initial response guidelines includes: Establishing a local cabinet for a diversified drive system in a nuclear power plant, the local cabinet for a diversified drive system adopts a power supply line different from that of the main control room and the remote shutdown room, and is connected to a battery, and the local cabinet for a diversified drive system is used to perform shutdown operations and containment isolation operations, monitor target parameters of the nuclear power plant, control and monitor the status of the reactor under accidents, and monitor and control safety-related systems of the nuclear power plant; Relying on the diversified drive system, the local cabinet executes the initial action recovery guide to confirm whether the nuclear power plant is shut down. If not, perform manual shutdown operation; if the nuclear power plant is shut down, confirm whether the target systems and equipment in the nuclear power plant are operating as designed. If the target systems and equipment are operating as designed, monitor the nuclear power plant parameters; if not, manually start the target systems and equipment to prevent secondary breaches and ensure the integrity of the reactor coolant system; Execute the communication recovery guidelines, obtain the communication status and the reason for the failure, and restore the communication; Implement the power plant damage assessment guidelines to obtain damage status assessment feedback for target objects within the nuclear power plant; Execute the initial response exit guidelines and provide the emergency response organization with initial response information, which includes the status of the emergency response organization in place, whether the initial response action is completed, the nuclear power plant damage status assessment feedback and whether the target communication is unobstructed.
4. The method according to claim 1, characterized in that The long-term mitigation process for implementing the extensive damage mitigation guidelines includes: Implement the power restoration guidelines to restore power within the nuclear power plant; When the core outlet temperature is higher than the preset temperature, the core charge control guideline is executed to control the reactor coolant system to depressurize, and gravity injection is started to restore the reactor coolant system charge; When the liquid level in the spent fuel pool is lower than the preset height, follow the spent fuel pool mitigation guidelines and perform spent fuel pool water replenishment and spraying operations; In the event that the accident lasts longer than the preset time and the temperature inside the containment continues to rise, the containment water replenishment guidelines shall be implemented; Implement long-term monitoring guidelines to monitor long-term concerns related to the implementation of long-term mitigation strategies.
5. The method according to claim 4, characterized in that The controlling the reactor coolant system to depressurize and start gravity injection includes: Through the on-site cabinet of the diversified drive system, confirm whether the relevant valves of the automatic pressure relief system and the built-in refueling water tank are opened. If they are opened, monitor the status and change trend of relevant parameters. If they are not opened, use the on-site cabinet of the diversified drive system to open the automatic pressure relief system valves and the relevant valves of the built-in refueling water tank, control the pressure relief of the reactor coolant system, and start gravity injection.
6. The method according to claim 4, characterized in that The guidelines for implementing long-term monitoring also include: Get the current status of the nuclear power plant.
7. The method according to claim 1, characterized in that Also includes: Follow the on-site execution guidelines after the emergency response organization is in place to obtain the information required for accident mitigation.
8. The method according to claim 1, characterized in that Also includes: Based on radiation protection principles and ambient temperature, route guidance rules leading to the local cabinet room of the diversified drive system are formulated.
9. The method according to claim 3, characterized in that The target systems and equipment include a passive residual heat removal system and a core water supply tank.
10. The method according to claim 3, characterized in that The damage status of the target object includes damage to key plant buildings, damage to target systems and equipment, reactor core status, containment integrity, status of important auxiliary support systems in the plant area, and availability of major water sources.