High-temperature reactor system and control method thereof

Abstract

The invention provides a high-temperature reactor system and a control method thereof, and relates to the technical field of nuclear power. Comprising a steam generator, a condenser, a steam turbine, a deaerator, a steam-water separator, a desalting water tank, a main pipeline, a first branch pipeline, a second branch pipeline, a third branch pipeline and a fourth branch pipeline. The steam generator, the steam turbine, the condenser and the deaerator are sequentially arranged on the main pipeline, the first branch pipeline is connected with the main pipeline in parallel, the steam-water separator is arranged on the first branch pipeline, and the second branch pipeline is connected between the water outlet end of the steam-water separator and the water inlet end of the deaerator. The third branch pipeline is connected between the gas outlet end of the steam-water separator and the gas inlet end of the deaerator, the fourth branch pipeline is connected between the desalting water tank and the water inlet end of the deaerator, and the high-temperature reactor system can maintain the operation of the reactor when the condenser fails.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of nuclear power, in particular to a high temperature reactor system and a control method thereof. BACKGROUND

[0002] During the process from starting to full power of the high temperature reactor system, the condenser needs to maintain a vacuum state all the time. When the vacuum of the condenser is lost, the turbine protection will be tripped, and the bypass valve will be locked, causing the interruption of the circulating loop, the abnormal rise of the main steam pressure, the frequent tripping of the atmospheric release valve or the safety valve, and finally the forced shutdown. Therefore, how to maintain the operation of the reactor when the condenser fails becomes a problem to be solved. SUMMARY

[0003] The purposes of the present application include, for example, providing a high temperature reactor system capable of maintaining the operation of the reactor when the condenser fails.

[0004] The purposes of the present application also include providing a control method of a high temperature reactor system capable of maintaining the operation of the reactor when the condenser fails.

[0005] Embodiments of the present application can be implemented as follows:

[0006] The embodiments of the present application provide a high temperature reactor system, which comprises a steam generator, a condenser, a turbine, a deaerator, a steam-water separator, a desalted water tank, a main pipeline, a first branch pipeline, a second branch pipeline, a third branch pipeline and a fourth branch pipeline.

[0007] The steam generator, the turbine, the condenser and the deaerator are sequentially arranged on the main pipeline, the first branch pipeline is connected in parallel with the main pipeline, the steam-water separator is arranged on the first branch pipeline, the second branch pipeline is connected between the water outlet of the steam-water separator and the water inlet of the deaerator, the third branch pipeline is connected between the gas outlet of the steam-water separator and the gas inlet of the deaerator, and the fourth branch pipeline is connected between the desalted water tank and the water inlet of the deaerator.

[0008] Optionally, a first regulating valve is arranged at the front end of the steam-water separator on the first branch pipeline, and an atmospheric discharge valve is arranged at the rear end of the steam-water separator on the first branch pipeline.

[0009] Optionally, a heat exchanger, a water feeding pump and a second regulating valve are arranged on the second branch pipeline.

[0010] Optionally, the heat exchanger is connected with a cooling pipeline, the cooling pipeline is provided with a cooling water pump and a third regulating valve, and the cooling water pump is used for pumping a cooling medium to the cooling pipeline.

[0011] Optionally, a gas source regulating valve is arranged on the third branch pipeline.

[0012] Optionally, the high temperature reactor system further comprises an electric boiler and a gas source branch connected between the electric boiler and the third sub-pipe.

[0013] Optionally, the fourth sub-pipe is provided with a make-up water pump and a fourth regulating valve.

[0014] Optionally, the main pipe is provided with a main feed water pump, a main feed water isolation valve and a safety valve, and the main pipe is provided with a nuclear island main steam isolation valve at the nuclear island side.

[0015] The application further provides a control method of a high temperature reactor system, applied to the high temperature reactor system, wherein the high temperature reactor system further comprises a reactor at a nuclear island side, the first sub-pipe is provided with a first regulating valve, the steam turbine is provided with a bypass valve in parallel, the main pipe is provided with a conventional island main steam isolation valve at a conventional island side, the second sub-pipe is provided with a heat exchanger, a feed water pump and a second regulating valve, the heat exchanger is connected and communicated with a cooling pipe, the cooling pipe is provided with a cooling water pump and a third regulating valve, the third sub-pipe is provided with a gas source regulating valve, and the fourth sub-pipe is provided with a make-up water pump and a fourth regulating valve.

[0016] The control method of the high temperature reactor system comprises the following steps.

[0017] When the condenser fails, the steam turbine is automatically tripped, the bypass valve is automatically closed, a large air exhaust valve is controlled to be opened, and the reactor is controlled to be reduced to a first preset power;

[0018] The make-up water pump is controlled to be started to supply water to a deaerator, and the opening degree of the fourth regulating valve is controlled to adjust the liquid level of the deaerator;

[0019] When the steam generator outlet steam temperature drops to a preset temperature, the first regulating valve is controlled to be opened, the conventional island main steam isolation valve is controlled to be closed, and the gas source regulating valve is controlled to be opened to heat and deaerate the deaerator;

[0020] The cooling water pump is controlled to be started to pump a cooling medium to the cooling pipe, the opening degree of the large air exhaust valve is controlled to adjust the pressure of a steam-water separator, and the opening degree of the first regulating valve is controlled to adjust the pressure of the steam generator;

[0021] The reactor is controlled to be reduced to a second preset power, and the large air exhaust valve is controlled to be closed.

[0022] Optionally, the high temperature reactor system further comprises an electric boiler and a gas source branch;

[0023] The control method of the high-temperature reactor system further comprises: when the steam flow provided by the steam-water separator is insufficient, controlling the electric boiler to start to heat and deaerate the deaerator through the gas source branch.

[0024] The high-temperature reactor system and the control method thereof provided by the embodiments of the present application have the following advantages: when the condenser cannot maintain vacuum or fails, the control system can quickly switch to the circulation mode dominated by the first branch, so that the steam no longer flows back to the condenser through the steam turbine, but directly enters the steam-water separator to complete steam-water separation, and the separated water and steam are transported to the deaerator through the second branch and the third branch respectively, and then output from the deaerator to the steam generator, thereby forming a closed loop circulation, and at the same time, the fourth branch starts the water supply function to ensure sufficient water in the deaerator and guarantee the continuity of the circulation. BRIEF DESCRIPTION OF DRAWINGS

[0025] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can also be obtained without creative labor.

[0026] Figure 1 FIG. 1 is a schematic diagram of a high-temperature reactor system in the embodiments of the present application.

[0027] Legend: 1-steam generator; 2-condenser; 3-steam turbine; 4-deaerator; 5-steam-water separator; 6-demineralized water tank; 7-main pipeline; 8-first branch; 9-second branch; 10-third branch; 11-fourth branch; 12-first regulating valve; 13-atmospheric discharge valve; 14-heat exchanger; 15-water feeding pump; 16-second regulating valve; 17-cooling pipeline; 18-cooling water pump; 19-third regulating valve; 20-gas source regulating valve; 21-electric boiler; 22-gas source branch; 23-water supply pump; 24-fourth regulating valve; 25-main water supply pump; 26-main water supply isolation valve; 27-safety valve; 28-nuclear island main steam isolation valve; 29-bypass valve; 30-conventional island main steam isolation valve; 31-condensate pump. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are some of the embodiments of the present application, not all the embodiments. The components of the embodiments of the present application described and shown in the drawings herein can be arranged and designed in various different configurations.

[0029] Therefore, the following detailed description of embodiments of the application provided in the accompanying drawings is not intended to limit the scope of the application as claimed, but merely represents selected embodiments of the application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative labor are within the scope of protection of the present application.

[0030] It should be noted that similar reference numbers and letters represent similar items in the following drawings, so once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings.

[0031] In the description of the present application, it should be noted that if the terms "upper", "lower", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present application is usually placed, it is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the indicated device or element must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application.

[0032] In addition, if the terms "first", "second" and the like appear, they are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0033] It should be noted that the features in the embodiments of the present application can be combined with each other without conflict.

[0034] The high temperature reactor system relies on the condenser to maintain a vacuum state during operation to achieve condensation of steam and stable operation of the circulating loop. When the condenser fails, the traditional system cannot maintain the main circulating path, resulting in problems such as turbine trip, steam discharge obstruction, and reactor forced shutdown.

[0035] Please refer to Figure 1 The embodiments of the present application provide a high temperature reactor system, comprising a steam generator 1, a condenser 2, a steam turbine 3, a deaerator 4, a steam-water separator 5, a desalted water tank 6, a main pipeline 7, a first branch pipeline 8, a second branch pipeline 9, a third branch pipeline 10 and a fourth branch pipeline 11; the steam generator 1, the steam turbine 3, the condenser 2 and the deaerator 4 are sequentially arranged on the main pipeline 7, the first branch pipeline 8 is connected in parallel with the main pipeline 7, the steam-water separator 5 is arranged on the first branch pipeline 8, the second branch pipeline 9 is connected between the water outlet end of the steam-water separator 5 and the water inlet end of the deaerator 4, the third branch pipeline 10 is connected between the gas outlet end of the steam-water separator 5 and the gas inlet end of the deaerator 4, and the fourth branch pipeline 11 is connected between the desalted water tank 6 and the water inlet end of the deaerator 4.

[0036] Steam generator 1, steam turbine 3, condenser 2, and deaerator 4 are sequentially arranged on main pipeline 7, forming the main circulation loop under normal operating conditions. First branch pipeline 8 is connected in parallel with main pipeline 7, and a steam-water separator 5 is installed on it. Second branch pipeline 9 connects the outlet of steam-water separator 5 and the inlet of deaerator 4, thus forming a backup circulation path that bypasses steam turbine 3 and condenser 2. This design ensures that when condenser 2 malfunctions, steam can enter steam-water separator 5 through first branch pipeline 8 for separation, avoiding system control failure caused by interruption of the original path.

[0037] The steam-water separator 5 has a water outlet and a steam outlet, which are connected to the water inlet and steam inlet of the deaerator 4 via the second branch pipe 9 and the third branch pipe 10, respectively, thus forming a water and steam transport path from the steam-water separator 5 to the deaerator 4. Through this path, the separated water can be directly returned to the deaerator 4 for subsequent feedwater circulation, while the separated steam is used to heat and deoxygenate the water inside the deaerator 4, ensuring that it has the thermal and chemical conditions required to re-enter the steam generator 1. The fourth branch pipe 11 connects the demineralized water tank 6 to the deaerator 4, serving as a supplementary water source when the condenser 2 is unavailable, ensuring water balance throughout the entire circulation process.

[0038] When condenser 2 fails to maintain vacuum or malfunctions, the control system can quickly switch to a circulation mode dominated by the first branch line 8. This prevents steam from returning via turbine 3 and condenser 2, and instead allows it to directly enter the steam-water separator 5 for separation, effectively avoiding excessive reliance on vacuum. The separated water and steam are then transported to deaerator 4 via the second branch line 9 and the third branch line 10, respectively, and then output from deaerator 4 to steam generator 1, thus forming a closed-loop cycle. Simultaneously, the fourth branch line 11 activates its water replenishment function to ensure sufficient water in deaerator 4 and guarantee the continuity of the circulation.

[0039] In this embodiment, a first regulating valve 12 is provided on the first branch pipe 8 at the front end of the steam-water separator 5, and an atmospheric vent valve 13 is provided on the first branch pipe 8 at the rear end of the steam-water separator 5.

[0040] The first regulating valve 12 is located at the front end of the steam-water separator 5 in the first branch pipeline 8. Its function is to regulate the steam flow rate from the steam generator 1 into the steam-water separator 5. Since the steam flow rate directly affects the internal pressure state of the steam generator 1, controlling the opening of the first regulating valve 12 can effectively regulate the steam pressure at the outlet of the steam generator 1, ensuring that it is maintained within the set safe range. This regulation mechanism not only helps prevent sudden pressure rises or falls caused by sudden changes in steam flow rate, but also allows for a smoother pressure transition in response to the dynamic requirements of reactor power adjustment.

[0041] Meanwhile, an atmospheric vent valve 13 is installed at the rear end of the steam-water separator 5 to control the rate at which the separated steam is discharged to the external environment. This atmospheric vent valve 13 is an adjustable valve, and its opening degree can be dynamically adjusted according to changes in the internal pressure of the steam-water separator 5, thereby maintaining the stability of the internal pressure. When the pressure inside the steam-water separator 5 exceeds a set threshold, the control system can increase the opening degree of the atmospheric vent valve 13 to release excess steam and prevent overpressure. Conversely, if the pressure is lower than the expected level, the opening degree can be appropriately reduced to suppress excessive steam discharge, thereby maintaining the continuity and controllability of the steam-water separator 5's operating state.

[0042] The first regulating valve 12 and the atmospheric vent valve 13 respectively control the pressure of the steam generator 1 and the steam-water separator 5, forming a coordinated control relationship. The first regulating valve 12 affects the pressure change of the upstream steam generator 1 by adjusting the inlet steam flow, while the atmospheric vent valve 13 affects the pressure response of the downstream steam-water separator 5 by controlling the downstream steam discharge path. This dual-stage pressure control not only improves the system's adaptability to complex working conditions, but also enhances the stability and safety of the entire circulation path.

[0043] It should be understood that in the standby cycle mode of the high-temperature reactor system, after the steam undergoes initial separation in the steam-water separator 5, the liquid water needs to be further cooled to a suitable temperature and returned to the deaerator 4 to maintain the continuity and thermal balance of the secondary loop. Since this water flow originates directly from the steam-water separator 5 and is at a high temperature, if it is returned to the deaerator 4 without treatment, it will disturb the internal operating conditions of the deaerator 4, affecting the quality of subsequent feedwater and the stability of the system.

[0044] In order to achieve effective treatment of this part of the water, in this embodiment, a heat exchanger 14, a water pump 15 and a second regulating valve 16 are installed on the second branch pipeline 9.

[0045] The heat exchanger 14 receives saturated water from the steam-water separator 5 and performs heat exchange treatment on it, reducing its temperature to the set range that meets the operating requirements of the deaerator 4. The water pump 15 is responsible for providing power to pressurize and deliver the heat-treated water to the deaerator 4, ensuring that the water flow can overcome system resistance and smoothly enter the next stage of heating and deaeration process. The function of the second regulating valve 16 is to regulate the water flow rate in the pipeline and to precisely manage the amount of water entering the deaerator 4 by controlling its opening, thereby maintaining the stability of water level and pressure throughout the entire circulation process.

[0046] Specifically, heat exchanger 14, as a heat energy conversion device, has an independent cooling channel inside for introducing a cooling medium (seawater or demineralized water) and exchanging heat with the high-temperature water from the steam-water separator 5. This allows the high-temperature water to cool down rapidly as it flows through heat exchanger 14, preventing excessive temperature from affecting the normal operation of deaerator 4. The upper water pump 15 is located downstream of heat exchanger 14, with its inlet connected to the outlet of heat exchanger 14 and its outlet connected to the inlet of deaerator 4. Through pumping, it ensures a continuous and stable flow of water into deaerator 4. A second regulating valve 16 is installed on the pipe section between upper water pump 15 and deaerator 4. Its opening is adjusted by the control system, allowing dynamic adjustment of the water flow rate under different operating conditions, thereby achieving precise control of the liquid level inside deaerator 4.

[0047] Furthermore, the heat exchanger 14 is connected to a cooling pipe 17, which is equipped with a cooling water pump 18 and a third regulating valve 19. The cooling water pump 18 is used to pump the cooling medium to the cooling pipe 17.

[0048] A cooling water pump 18 is installed on the cooling pipe 17. Its function is to provide driving force to pump the cooling medium from an external water source to the cooling channel of the heat exchanger 14, and discharge it to the recovery system or discharge point after heat exchange is completed. The start-up, shutdown and output pressure of the cooling water pump 18 are controlled by the system control logic, which can dynamically adjust according to the actual heat load demand at different operating stages to ensure that the heat exchanger 14 has sufficient cooling capacity.

[0049] The third regulating valve 19 is installed on the cooling pipe 17, located between the cooling water pump 18 and the heat exchanger 14. Its opening can be adjusted in real time according to the temperature changes inside the heat exchanger 14. By controlling the opening of the third regulating valve 19, the flow rate of the cooling medium can be adjusted, thereby achieving precise management of the cooling capacity of the heat exchanger 14. When the water temperature discharged from the steam-water separator 5 is high, the control system can increase the opening of the third regulating valve 19 to allow more cooling medium to flow into the heat exchanger 14, improving its cooling effect; conversely, when the water temperature is low, the opening can be appropriately reduced to avoid over-cooling and energy waste.

[0050] The coordinated action of the cooling water pump 18 and the third regulating valve 19 ensures that the heat exchanger 14 maintains good heat exchange performance under various operating conditions. The cooling water pump 18 ensures a continuous supply of cooling medium, while the third regulating valve 19 enables precise adjustment of the cooling capacity. Together, they not only improve the adaptability of the heat exchanger 14 to different operating conditions but also enhance the stability and controllability of the entire standby circulation loop.

[0051] It should be understood that the third branch pipe 10 is connected between the gas outlet of the steam-water separator 5 and the gas inlet of the deaerator 4, forming a steam transport path from the steam-water separator 5 to the deaerator 4. In order to achieve controllable adjustment of the steam flow and pressure on this path, in this embodiment, a gas source regulating valve 20 is provided on the third branch pipe 10.

[0052] The opening degree of the gas source regulating valve 20 can be dynamically adjusted according to the changes in internal pressure, temperature and steam load of the deaerator 4, thereby achieving precise management of the steam flow entering the deaerator 4.

[0053] When the steam pressure or flow rate discharged from the steam-water separator 5 exceeds the range required by the deaerator 4, the control system can limit the steam inflow rate by reducing the opening of the gas source regulating valve 20, thus preventing a sudden increase in internal pressure or excessive temperature in the deaerator 4. Conversely, when the steam supply is insufficient or the heating rate needs to be accelerated, the opening of the gas source regulating valve 20 can be appropriately increased to enhance the heating capacity of the deaerator 4. This dynamic adjustment mechanism enables the deaerator 4 to maintain a stable thermal environment under different operating conditions, ensuring its deoxygenation effect and water supply quality.

[0054] It should be understood that in the standby operation mode of the high-temperature reactor system, the steam discharged from the steam-water separator 5 is used as the main heating steam source for the deaerator 4 to maintain the temperature and deoxygenation efficiency of the water inside the deaerator 4. However, when the amount of steam provided by the steam-water separator 5 is insufficient to meet the heating requirements of the deaerator 4, or when there is no stable steam supply at the beginning of system startup, the lack of corresponding supplementary heating methods may cause the deaerator 4 to malfunction, thereby affecting the establishment and stable operation of the entire secondary loop. To solve the above problems, in this embodiment, the high-temperature reactor system also includes an electric boiler 21 and a gas source branch 22, which is connected between the electric boiler 21 and the third branch pipeline 10.

[0055] As an independent steam generating unit, the electric boiler 21's main function is to provide additional heating steam to support the normal operation of the deaerator 4 when the steam supply is insufficient. To this end, the electric boiler 21 is connected to the third branch pipeline 10 through the gas source branch 22, so that the steam it generates can flow into the third branch pipeline 10 and finally be delivered to the deaerator 4.

[0056] Gas source branch 22 serves as an additional path connecting electric boiler 21 and the third branch pipeline 10. One end of it connects to the steam outlet of electric boiler 21, and the other end connects to the position near the air inlet of deaerator 4 in the third branch pipeline 10, thus forming an independent steam input channel. Appropriate valves can be configured on this gas source branch 22 according to actual needs to control the steam flow and regulate the pressure. When the steam flow or temperature provided by steam-water separator 5 fails to meet the parameters required by deaerator 4, the control system can start electric boiler 21 and open the corresponding valve on gas source branch 22, allowing the steam generated by electric boiler 21 to enter the third branch pipeline 10, mix with the steam output from steam-water separator 5, and work together to act on deaerator 4. When steam-water separator 5 can stably supply steam, electric boiler 21 can be in standby mode, only being put into operation when needed.

[0057] The fourth branch pipeline 11 serves as an independent makeup water path connecting the demineralized water tank 6 and the inlet of the deaerator 4. Its function is to replace the traditional makeup water method during condenser 2 failure or maintenance, supplying makeup water to the deaerator 4 for heating, deaeration, and subsequent circulation. To ensure the controllability and stability of this makeup water process, in this embodiment, a makeup water pump 23 and a fourth regulating valve 24 are sequentially installed on the fourth branch pipeline 11.

[0058] The water supply pump 23 is used to pump the demineralized water in the demineralized water tank 6 to the deaerator 4, overcoming pipeline resistance and ensuring that water can smoothly enter the deaerator 4; the fourth regulating valve 24 is used to regulate the amount of water supply flowing through the fourth branch pipeline 11, so that it can be dynamically adjusted according to the changes in the liquid level of the deaerator 4 and the system operation requirements, thereby maintaining the stability of the water level in the deaerator 4.

[0059] Specifically, the makeup water pump 23 is installed on the fourth branch pipeline 11. Its inlet end is connected to the demineralized water tank 6, and its outlet end is connected to the inlet end of the deaerator 4. The start-up, shutdown, and output pressure of the makeup water pump 23 are automatically adjusted by the control system according to the actual operating parameters. It can be started quickly when the condenser 2 is unavailable to fill the water shortage caused by the interruption of the main circulation path. The inlet end of the deaerator 4 connected to the upper water pump 15 and the inlet end of the deaerator 4 connected to the makeup water pump 23 can be the same inlet end or two different inlets, which is not limited.

[0060] The fourth regulating valve 24 is located downstream of the water supply pump 23, near the inlet of the deaerator 4. During system operation, it adjusts its opening in real time according to changes in the water level inside the deaerator 4, thereby achieving precise control of the water supply. For example, when the water level in the deaerator 4 is lower than the set value, the control system can increase the opening of the fourth regulating valve 24 to increase the water supply, and vice versa to reduce the opening to avoid the water level from becoming too high.

[0061] In this embodiment, the main feedwater pump 25, the main feedwater isolation valve 26 and the safety valve 27 are provided on the main feedwater pipeline 7, and the nuclear island main steam isolation valve 28 is provided on the nuclear island side of the main feedwater pipeline 7.

[0062] The main feedwater pump 25 pumps water from the deaerator 4 to the steam generator 1 to maintain continuous water flow in the main circulation path. The main feedwater isolation valve 26 is located downstream of the main feedwater pump 25, on the pipe section between the main feedwater pump 25 and the steam generator 1. It is used to cut off the main feedwater flow when necessary, achieving physical isolation of the main circulation path. For example, in the event of system maintenance, equipment failure, or emergency shutdown, the control system can close the main feedwater isolation valve 26 to prevent water from entering the steam generator 1, while facilitating subsequent maintenance operations. This isolation valve can be electrically or pneumatically driven, enabling it to open or close quickly.

[0063] A condensate pump 31 is installed at the rear end of condenser 2 on the main pipeline 7. During normal operation of the high-temperature reactor system, the main feedwater isolation valve 26 and the main steam isolation valve are open, while the safety valve 27 and the atmospheric vent valve 13 are closed. The condensate pump 31 transports the condensate in condenser 2 to deaerator 4, where it is heated and deaerated by electric boiler 21. Then, it is pumped by main feedwater pump 25 to steam generator 1 for heat exchange. After being heated, the water becomes superheated steam, which is then sent to turbine 3 to perform work. Turbine 3 drives generator to produce electricity, completing the conversion from nuclear energy to electrical energy. Finally, the steam discharged from turbine 3 re-enters condenser 2 and condenses back into condensate to achieve circulation. Condenser 2 is cooled by circulating water, and in conjunction with the vacuum system, a vacuum state is maintained.

[0064] Safety valve 27 is mainly used to limit the steam pressure at the outlet of steam generator 1 to prevent equipment damage or safety accidents caused by overpressure. When the steam pressure in the main pipeline 7 exceeds the set safety threshold, safety valve 27 automatically opens to release excess steam to the designated discharge area, thereby effectively relieving system pressure; after the pressure drops back to the normal range, safety valve 27 closes again.

[0065] The high-temperature reactor system also includes a reactor located on the nuclear island side (not shown in the figure). The main steam isolation valve 28 of the nuclear island is mainly used to quickly cut off the steam transmission from the nuclear island to the conventional island under extreme operating conditions (such as emergency reactor shutdown) to prevent steam backflow or abnormal diffusion and ensure the safe isolation of equipment on the nuclear island side.

[0066] In addition, a bypass valve 29 is installed in parallel with the steam turbine 3. The bypass valve 29 can be automatically closed when the condenser 2 fails, and can be opened by the control system. The steam turbine 3 can be automatically tripped when the condenser 2 fails. The main pipeline 7 is equipped with a conventional island main steam isolation valve 30 on the conventional island side.

[0067] The turbine 3 is configured to automatically trip in the event of a condenser 2 failure. Here, "condenser failure" refers to the condenser 2's inability to maintain the vacuum required for normal operation, such as a decrease in vacuum due to a malfunction in the vacuum system. When the control system detects that the vacuum level of condenser 2 is below a set threshold or receives a relevant fault signal, it determines that condenser 2 is unusable and immediately triggers the turbine 3 protection trip. After the turbine 3 trips, the path for steam to flow from its interior to condenser 2 is cut off, and simultaneously, the bypass valve 29 automatically closes.

[0068] The conventional island side refers to the area of ​​the system far from the reactor. The conventional island main steam isolation valve 30 is installed on the pipe section upstream of the turbine 3 and connected in parallel with the first branch pipe 8. Its function is to quickly cut off the steam transmission from the nuclear island to the conventional island under specific operating conditions. For example, if the condenser 2 completely fails and the turbine 3 has tripped, the control system can further close the conventional island main steam isolation valve 30 to physically isolate the steam flow to the equipment on the conventional island side, thereby reducing the risk of system runaway and ensuring the safety of maintenance operations.

[0069] This embodiment also provides a control method for a high-temperature reactor system, applied to the aforementioned high-temperature reactor system. The control method for the high-temperature reactor system includes:

[0070] Step 1: When condenser 2 fails, turbine 3 automatically trips, bypass valve 29 automatically closes, atmospheric exhaust valve 13 is opened, and reactor power is reduced to the first preset power.

[0071] Step 2: Control the start of the water supply pump 23 to supply water to the deaerator 4, and control the opening of the fourth regulating valve 24 to adjust the liquid level in the deaerator 4.

[0072] Step 3: When the outlet steam temperature of steam generator 1 drops to the preset temperature, control the first regulating valve 12 to open, the conventional island main steam isolation valve 30 to close, and control the gas source regulating valve 20 to open, so as to heat and deoxygenate deaerator 4.

[0073] Step 4: Start the cooling water pump 18 to pump the cooling medium into the cooling pipe 17;

[0074] Step 5: Control the opening of the atmospheric discharge valve 13 to regulate the pressure of the steam-water separator 5, and control the opening of the first regulating valve 12 to regulate the pressure of the steam generator 1.

[0075] Step 6: Control the reactor to reduce to the second preset power and control the atmospheric vent valve 13 to close.

[0076] It should be noted that all control actions are executed through the control system, including the controller. In step one, when condenser 2 fails, bypass valve 29 automatically closes to cut off the path for steam to bypass turbine 3 and flow directly into condenser 2. At the same time, atmospheric exhaust valve 13 is opened to form a steam pressure relief channel, releasing superheated steam to the external environment and alleviating the system pressure rise. In addition, to reduce heat input and lower the load on subsequent equipment, the reactor power is reduced to a first preset power (e.g., 70MW), causing the steam generator 1 to produce steam accordingly, thereby reducing the system operating pressure.

[0077] In step two, the control system starts the water supply pump 23 to pump water from the demineralized water tank 6 to the deaerator 4 to replenish the water lost due to the interruption of the main circulation path, ensuring that the deaerator 4 has a continuous water supply capacity. At the same time, the opening of the fourth regulating valve 24 is dynamically adjusted according to the liquid level feedback signal of the deaerator 4 to accurately control the amount of water replenished, so that the water level inside the deaerator 4 is always maintained within the set safe range, avoiding excessively high or low water levels from affecting the stability and safety of the subsequent water supply process.

[0078] In step three, when the control system detects that the outlet steam temperature of steam generator 1 drops to a preset temperature (e.g., from 520°C to 400°C), the physical conditions for switching to the backup circulation path are met. At this time, the first regulating valve 12 is opened, allowing steam to flow from steam generator 1 to steam-water separator 5, establishing a new steam-water circulation path; simultaneously, the main steam isolation valve 30 of the conventional island is closed to physically isolate the main steam transmission path between the nuclear island and the conventional island, preventing steam from continuing to flow into the failure area of ​​condenser 2, ensuring equipment safety and providing isolation conditions for subsequent maintenance; based on this, the gas source regulating valve 20 is opened, allowing heating steam from steam-water separator 5 to enter deaerator 4 for heating and deoxygenating the water inside.

[0079] In step four, the control system starts the cooling water pump 18 to deliver the cooling medium to the heat exchanger 14, which cools the high-temperature water discharged from the steam-water separator 5 to a suitable temperature before delivering it to the deaerator 4.

[0080] In step five, the control system controls the opening of the atmospheric vent valve 13 in a timely manner based on the feedback data from the pressure sensor inside the steam-water separator 5 to maintain the pressure stability inside the steam-water separator 5 and prevent overpressure. At the same time, the control system controls the opening of the first regulating valve 12 to regulate the steam flow from the steam generator 1 into the steam-water separator 5, thereby indirectly regulating the pressure level at the outlet of the steam generator 1. By controlling the opening of the atmospheric vent valve 13 and the first regulating valve 12, the control system achieves dual-stage pressure control, which helps to improve the stability and response accuracy of the entire standby cycle path.

[0081] In step six, as the high-temperature reactor system gradually transitions to a stable operating state, the control system further reduces the reactor power to a second preset power (e.g., 20MW), enabling the high-temperature reactor system to enter a steady-state mode that can be maintained for a long time. At this time, the steam generator 1 is filled with saturated water, and the control system controls the atmospheric discharge valve 13 to close, so that steam is no longer discharged. The high-temperature reactor system is completely switched to a closed-loop circulation path dominated by the steam-water separator 5.

[0082] In addition, the control method of the high-temperature reactor system also includes: when the steam flow provided by the steam-water separator 5 is insufficient, controlling the electric boiler 21 to start so as to heat and deoxygenate the deaerator 4 through the gas source branch 22.

[0083] During certain operational phases of the high-temperature reactor system (such as when steam separator 5 is not yet providing stable steam supply), relying solely on steam from steam separator 5 may not meet the heating power requirements of deaerator 4, thus affecting deaeration efficiency and the thermal stability of the entire secondary loop. In such cases, it is necessary to start the electric boiler 21 and deliver its steam to deaerator 4 via gas source branch 22 as a supplement or even alternative source of steam supplied by steam separator 5.

[0084] When the control system detects that the steam flow rate or temperature delivered from the steam-water separator 5 to the deaerator 4 is lower than the set threshold, it indicates that the current steam supply is insufficient to maintain the heating load required by the deaerator 4. At this time, the control system will start the electric boiler 21 and open the relevant valves on the gas source branch 22, so that the steam generated by the electric boiler 21 flows into the third branch pipeline 10 through the gas source branch 22 and finally enters the deaerator 4.

[0085] The operating power of the electric boiler 21 can be adjusted according to the actual needs of the deaerator 4 to avoid excessive steam supply causing excessive internal pressure in the deaerator 4, or insufficient steam supply affecting the deaeration effect.

[0086] For example, during normal operation of the high-temperature reactor system, the reactor maintains a 200MW operation, a feedwater flow rate of 75kg / s, a main steam temperature of 520°C, and a main steam pressure of 11MPa.

[0087] When condenser 2 fails, bypass valve 29 automatically closes, atmospheric vent valve 13 is opened, steam generator 1 pressure is adjusted to 11MPa, and reactor power is reduced at a rate of 5%RFP / min until the power is reduced to about 70MW. During this process, steam is mainly discharged through atmospheric vent valve 13. Then, water pump 23 is started to supply water to deaerator 4 to maintain secondary loop circulation.

[0088] When the steam temperature at the outlet of steam generator 1 drops from 520℃ to approximately 400℃, the first regulating valve 12 is opened, the main steam isolation valve 30 of the conventional island is closed, and the gas source regulating valve 20 is opened to heat and deaerate the deaerator 4; simultaneously, the cooling water pump 18 is started to pump cooling medium into the cooling pipe 17; at this time, the opening of the atmospheric vent valve 13 is controlled to adjust the pressure of the steam-water separator 5 to 5MPa, and the opening of the first regulating valve 12 is controlled to adjust the pressure of steam generator 1 to 11MPa; the pressure inside the steam-water separator 5 is 5MPa. Saturated water at around 286℃ is cooled by heat exchanger 14 to about 0.6MPa and 160℃. Throughout the process, the steam from the outlet of steam-water separator 5 is used as the heating gas source for deaerator 4, while electric boiler 21 is in standby mode. When the temperature of steam generator 1 drops to 318℃, the steam generator 1 is filled with saturated water, and the heating gas source is switched to electric boiler 21. The reactor is then controlled to operate at 20MW. At this point, both loops are water-based and can circulate stably for a long time. During this period, atmospheric exhaust valve 13 is kept closed.

[0089] In addition, the startup process of the high-temperature reactor system is divided into two stages: the first stage is the standby cycle operation stage when the condenser 2 has not established a vacuum, and the second stage is the main loop switching stage after the condenser 2 has established a vacuum.

[0090] In the first stage, before the condenser 2 establishes a vacuum, the high-temperature reactor system initially starts up with heating steam supplied by the electric boiler 21. This steam is then delivered to the deaerator 4 via the gas source branch 22 for preliminary heating and deoxygenation of the water within the deaerator 4. Once the steam-water separator 5 generates steam, the heating steam source is switched. Simultaneously, the makeup water pump 23 is started, pumping water from the demineralized water tank 6 to the deaerator 4. The level of the demineralized water is regulated by the fourth regulating valve 24 to ensure a stable water supply to the deaerator 4. Subsequently, the main feedwater pump 25 delivers the deaerated water to the steam generator 1, where steam is generated under the reactor's thermal power. At this point, the main steam isolation valve 30 of the conventional island is closed, and the first regulating valve 12 is opened, guiding the steam to the first branch line 8 and then through the first regulating valve 12 into the steam-water separator 5. During the initial startup of the cooling water pump 18, the third regulating valve 19 is opened only slightly to avoid excessive heat loss.

[0091] In the steam-water separator 5, liquid water flows out through the second branch pipe 9 and is cooled by the heat exchanger 14 before returning to the deaerator 4, forming a water-side circulation; while saturated steam is regulated by the gas source regulating valve 20 through the third branch pipe 10 and re-enters the deaerator 4 as a heating steam source, thus forming a steam-side circulation.

[0092] Even without a vacuum in condenser 2, the high-temperature reactor system can establish a complete steam-water circulation loop independent of condenser 2 by activating steam-water separator 5 and its related piping structure. This allows the reactor to start up safely and operate continuously at low power, avoiding wasted time waiting for condenser 2 to prepare.

[0093] In the second stage, after the condenser 2 completes vacuum establishment, the vacuum system is in normal operation, and the relevant parameters meet the operating requirements, the control system performs a switching operation from the standby circulation loop to the main loop. Specifically, the bypass valve 29 and the main steam isolation valve 30 of the conventional island are opened, and the first regulating valve 12 is closed, allowing steam to flow back through the turbine 3 into the condenser 2. As steam enters the main loop, the cooling water pump 18 and the feed water pump 15 can be taken out of operation, and the makeup water source is switched back from the demineralized water tank 6 to the condenser 2, completing the transition of the entire secondary loop from standby mode to conventional operation mode.

[0094] In summary, the embodiments of this application provide a high-temperature reactor system and its control method. When the condenser 2 cannot maintain a vacuum or malfunctions, the control system can quickly switch to a circulation mode dominated by the first branch pipeline 8, so that the steam no longer flows back through the turbine 3 and the condenser 2, but directly enters the steam-water separator 5 to complete steam-water separation. The water and steam separated by the steam-water separator 5 are respectively transported to the deaerator 4 through the second branch pipeline 9 and the third branch pipeline 10, and then output from the deaerator 4 to the steam generator 1, thus forming a closed loop circulation. At the same time, the fourth branch pipeline 11 starts the water replenishment function to ensure that the water in the deaerator 4 is sufficient and to ensure the continuity of the circulation.

[0095] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A high temperature reactor system, characterized by, The steam generator (1), the condenser (2), the steam turbine (3), the deaerator (4), the steam-water separator (5), the desalted water tank (6), the main pipeline (7), the first branch pipeline (8), the second branch pipeline (9), the third branch pipeline (10) and the fourth branch pipeline (11) are arranged in sequence on the main pipeline (7); The steam generator (1), the condenser (2), the steam turbine (3) and the deaerator (4) are arranged in sequence on the main pipeline (7), the first branch pipeline (8) is connected with the main pipeline (7) in parallel, the steam-water separator (5) is arranged on the first branch pipeline (8), the second branch pipeline (9) is connected between the water outlet of the steam-water separator (5) and the water inlet of the deaerator (4), the third branch pipeline (10) is connected between the gas outlet of the steam-water separator (5) and the gas inlet of the deaerator (4), and the fourth branch pipeline (11) is connected between the desalted water tank (6) and the water inlet of the deaerator (4).

2. The high temperature reactor system of claim 1, wherein, A first regulating valve (12) is arranged on the first branch pipeline (8) at the front end of the steam-water separator (5), and an atmospheric discharge valve (13) is arranged on the first branch pipeline (8) at the rear end of the steam-water separator (5).

3. The high temperature reactor system of claim 1, wherein, A heat exchanger (14), a water pump (15) and a second regulating valve (16) are arranged on the second branch pipeline (9).

4. The high temperature reactor system of claim 3, wherein, The heat exchanger (14) is connected with a cooling pipeline (17), the cooling pipeline (17) is provided with a cooling water pump (18) and a third regulating valve (19), and the cooling water pump (18) is used for pumping a cooling medium to the cooling pipeline (17).

5. The high temperature reactor system of claim 1, wherein, A gas source regulating valve (20) is arranged on the third branch pipeline (10).

6. The high temperature reactor system of claim 1, wherein, The high-temperature reactor system further comprises an electric boiler (21) and a gas source branch (22), and the gas source branch (22) is connected between the electric boiler (21) and the third branch pipeline (10).

7. The high temperature reactor system of claim 1, wherein, A water supplement pump (23) and a fourth regulating valve (24) are arranged on the fourth branch pipeline (11).

8. The high temperature reactor system of claim 1, wherein, A main water supply pump (25), a main water supply isolation valve (26) and a safety valve (27) are arranged on the main pipeline (7), and a nuclear island main steam isolation valve (28) is arranged on the nuclear island side of the main pipeline (7).

9. A method of controlling a high temperature reactor system, characterized by, The high-temperature reactor system further comprises a reactor on the nuclear island side, a first regulating valve (12) is arranged on the first branch pipeline (8), a bypass valve (29) is arranged in parallel with the steam turbine (3), a conventional island main steam isolation valve (30) is arranged on the conventional island side of the main pipeline (7), a heat exchanger (14), a water pump (15) and a second regulating valve (16) are arranged on the second branch pipeline (9), the heat exchanger (14) is connected with a cooling pipeline (17), the cooling pipeline (17) is provided with a cooling water pump (18) and a third regulating valve (19), a gas source regulating valve (20) is arranged on the third branch pipeline (10), and a water supplement pump (23) and a fourth regulating valve (24) are arranged on the fourth branch pipeline (11). The control method of the high-temperature reactor system comprises: When the condenser (2) fails, the turbine (3) is automatically tripped, the bypass valve (29) is automatically closed, the atmospheric discharge valve (13) is controlled to open, and the reactor is controlled to reduce to a first preset power; The feedwater pump (23) is controlled to start to supply water to the deaerator (4), and the opening degree of the fourth regulating valve (24) is controlled to adjust the liquid level of the deaerator (4); When the outlet steam temperature of the steam generator (1) drops to a preset temperature, the first regulating valve (12) is controlled to open, the conventional island main steam isolation valve (30) is controlled to close, and the gas source regulating valve (20) is controlled to open to perform heating deaeration on the deaerator (4); The cooling water pump (18) is controlled to start to pump the cooling medium to the cooling pipeline (17), the opening degree of the atmospheric discharge valve (13) is controlled to adjust the pressure of the steam-water separator (5), and the opening degree of the first regulating valve (12) is controlled to adjust the pressure of the steam generator (1); The reactor is controlled to reduce to a second preset power, and the atmospheric discharge valve (13) is controlled to close.

10. The method of controlling a high temperature reactor system according to claim 9, wherein, The high-temperature reactor system further comprises an electric boiler (21) and a gas source branch (22); When the steam flow provided by the steam-water separator (5) is insufficient, the electric boiler (21) is controlled to start to perform heating deaeration on the deaerator (4) through the gas source branch (22).

Images