Nuclear power generation steam supply system and use method thereof

Abstract

The invention belongs to the technical field of nuclear power, and particularly relates to a nuclear power generation steam supply system and a using method thereof. The nuclear energy power generation steam supply system comprises a sodium-cooled fast reactor, an intermediate heat exchanger, a secondary loop sodium pump, a sodium-fused salt heat exchanger, a low-temperature fused salt conveying pump, a first adjusting valve, a low-temperature fused salt tank, a high-temperature fused salt tank, a second adjusting valve, a high-temperature fused salt conveying pump, a fused salt-water heat exchanger, a steam loop control valve, a power generation loop control valve, a superheater and a main water feeding pump. The invention discloses a steam turbine generator, a check valve and a condenser. By adopting a sodium-sodium-fused salt-water four-loop design, the problems that the possibility of sodium-water reaction is not eliminated and peak regulation and frequency modulation capabilities are not achieved due to the fact that an existing fast reactor adopts a sodium-sodium-water three-loop design are solved.

Description

Technical Field

[0001] The present application belongs to the field of nuclear power technology, and specifically relates to a nuclear power generation steam supply system and a method of using the same. Background Art

[0002] The nuclear power plants that have been built so far do not have the ability to regulate peak and frequency. Traditional frequency and peak regulation are at the expense of unit output. Although part of the cost is compensated by subsidies for frequency and peak regulation electricity prices, the long-term participation in frequency and peak regulation will result in the wasted reactor power with an objective economic value.

[0003] In addition, as the main reactor type of the fourth generation of nuclear power, fast reactors represent the future development direction of nuclear power. However, the current fast reactor adopts a sodium-sodium-water three-circuit design, which has not yet eliminated the possibility of sodium-water reaction. Summary of the invention

[0004] In view of this, the present application is committed to providing a nuclear power generation steam supply system and its use method, which adopts a sodium-sodium-molten salt-water four-circuit design to solve the problem that the existing fast reactor adopts a sodium-sodium-water three-circuit design, has not eliminated the possibility of sodium-water reaction and does not have peak-shaving and frequency regulation capabilities.

[0005] The first aspect of the present application provides a nuclear power generation steam supply system, which includes a sodium-cooled fast reactor, an intermediate heat exchanger, a secondary circuit sodium pump, a sodium-molten salt heat exchanger, a low-temperature molten salt delivery pump, a first regulating valve, a low-temperature molten salt tank, a high-temperature molten salt tank, a second regulating valve, a high-temperature molten salt delivery pump, a molten salt-water heat exchanger, a steam circuit control valve, a power generation circuit control valve, a superheater, a main feed water pump, a steam turbine generator, a check valve and a condenser. The intermediate heat exchanger is immersed in the sodium pool of the sodium-cooled fast reactor. The secondary circuit sodium pump is connected in series between the outlet end of the intermediate heat exchanger and the inlet end of the sodium side of the sodium-molten salt heat exchanger. The inlet end of the intermediate heat exchanger is connected to the outlet end of the sodium side of the sodium-molten salt heat exchanger. The outlet end of the molten salt fluid side of the sodium-molten salt heat exchanger is connected in series with the high-temperature molten salt tank, the second regulating valve, the high-temperature molten salt delivery pump and the inlet end of the molten salt fluid side of the molten salt-water heat exchanger. The inlet end of the molten salt fluid side of the sodium-molten salt heat exchanger is connected in series with the low-temperature molten salt delivery pump, the first regulating valve, the low-temperature molten salt tank and the outlet end of the molten salt fluid side of the molten salt-water heat exchanger in sequence. The outlet end of the water side of the molten salt-water heat exchanger is connected in series with the power generation circuit control valve, the superheater, the steam turbine generator, the check valve and the steam user. One end of the steam circuit control valve is connected between the outlet end of the water side of the molten salt-water heat exchanger and the power generation circuit control valve, and the other end of the steam circuit control valve is connected to the pipeline between the check valve and the steam user. The inlet end of the water side of the molten salt-water heat exchanger is connected in series with the main feed water pump and the condenser in sequence, and then connected to the pipeline between the steam turbine generator and the check valve.

[0006] In a specific embodiment of the present application, the nuclear power generation steam supply system also includes a photothermal energy storage system. The photothermal energy storage system is arranged on the outside of the molten salt pipeline between the outlet end of the molten salt fluid side of the sodium-molten salt heat exchanger and the high-temperature molten salt tank. In the photothermal energy storage mode, the sodium-cooled fast stack is maintained at full power, the sodium pump and the high-temperature molten salt delivery pump are operated at rated power, the photothermal energy storage system is used to heat the molten salt pipeline, and the low-temperature molten salt delivery pump is operated at high power.

[0007] In a specific embodiment of the present application, the solar thermal energy storage system adopts a linear Fresnel concentrating system.

[0008] In a specific embodiment of the present application, the sodium-molten salt heat exchanger adopts a double-layer tube design, and an inert gas is used between the double-layer tubes. Hot medium flows inside the double-layer tube, and cold medium flows on the double-layer tube shell side.

[0009] In a specific embodiment of the present application, the nuclear power generation steam supply system also includes a main transformer, an energy storage transformer, a super capacitor and a nuclear-grade battery pack. The power generation outlet of the steam turbine generator is connected in series with the main transformer and the power grid user in sequence. The super capacitor and the energy storage transformer are connected in series in sequence and in parallel with the connecting pipe between the power generation outlet of the steam turbine generator and the main transformer. The super capacitor is connected to the nuclear-grade battery pack for timed charging and discharging of the nuclear-grade battery pack.

[0010] The second aspect of the present application provides a method for using a nuclear power generation steam supply system, which is performed using a nuclear power generation steam supply system of the first aspect of the present application. In all modes, the sodium-cooled fast reactor operates at full power. The low-temperature molten salt delivery pump and the high-temperature molten salt delivery pump are variable frequency pumps, and their operating conditions are set with low power, rated power and high power operating modes. The nuclear power generation steam supply system has a power generation mode and a high-temperature industrial steam supply mode. The method for using the nuclear power generation steam supply system includes:

[0011] When the nuclear power generation steam supply system is in power generation mode, open the first regulating valve, the second regulating valve and the power generation circuit control valve, close the steam circuit control valve, and operate the low-temperature molten salt delivery pump and the high-temperature molten salt delivery pump at rated power. At this time, the liquid levels of the high-temperature molten salt tank and the low-temperature molten salt tank remain unchanged. The condensate is transported by the main feed water pump through the molten salt-water heat exchanger for heat exchange, and then becomes saturated steam through the superheater, and finally generates electricity through the steam turbine generator. The exhaust steam of the steam turbine in the steam turbine generator can be transported to the steam user;

[0012] When the nuclear power generation steam supply system is in the high-temperature industrial steam supply mode, the first regulating valve, the second regulating valve and the steam circuit control valve are opened, the power generation circuit control valve is closed, the low-temperature molten salt delivery pump and the high-temperature molten salt delivery pump are operated at rated power, and the liquid levels of the high-temperature molten salt tank and the low-temperature molten salt tank remain unchanged. The condensate is transported by the main feed water pump through the molten salt-water heat exchanger for heat exchange, and the generated high-temperature industrial steam is directly transported to the steam user.

[0013] In a specific embodiment of the present application, the nuclear power generation steam supply system also has a primary frequency regulation and peak regulation mode. The method for using the nuclear power generation steam supply system also includes: when the nuclear power generation steam supply system is in the primary frequency regulation and peak regulation mode, mode one or mode two is used when the power is reduced. Mode three is used when the power is increased.

[0014] Mode 1: The secondary circuit sodium pump operates at full power, the low-temperature molten salt delivery pump operates at rated power, the high-temperature molten salt delivery pump operates at low power, and the main feed water pump operates at low power.

[0015] Mode 2: While starting the power generation mode of the nuclear power generation steam supply system, the high-temperature industrial steam supply mode of the nuclear power generation steam supply system is also started, and the amount of industrial steam supply is controlled by the opening of the steam loop control valve.

[0016] Mode 3: The secondary circuit sodium pump operates at full power, the low-temperature molten salt delivery pump maintains rated power operation, and the high-temperature molten salt delivery pump and the main feed water pump operate at high power.

[0017] In a specific embodiment of the present application, the method for using the nuclear power generation steam supply system also includes: when the power is reduced, the power generation mode of the nuclear power generation steam supply system is maintained unchanged, and the supercapacitor and the nuclear-grade battery group are synchronously connected to the power generation outlet of the steam turbine generator for charging; when the power is increased, the power generation mode of the nuclear power generation steam supply system is maintained unchanged, and the supercapacitor and the nuclear-grade battery group are synchronously connected to the grid-connected end of the power station for discharging.

[0018] The beneficial effect of the technical solution of the present application is that: by setting the sodium-molten salt heat exchanger, low-temperature molten salt tank, high-temperature molten salt tank and other structures and their connection relationships in the nuclear power generation steam supply system, the nuclear power generation steam supply system adopts a sodium-sodium-molten salt-water four-circuit design. Compared with the existing fast reactor with a sodium-sodium-water three-circuit design (the possibility of sodium-water reaction has not been eliminated), the nuclear power generation steam supply system can effectively ensure the isolation of sodium from molten salt and water, and avoid sodium-water and other reactions. In addition, by controlling the power of the low-temperature molten salt delivery pump and the high-temperature molten salt delivery pump and the opening of the steam circuit control valve, the steam amount to the steam turbine generator is adjusted, thereby controlling the power generation power of the steam turbine generator, so that the nuclear power generation steam supply system has good frequency modulation and peak regulation capabilities. In addition, by controlling the opening and closing of the first regulating valve, the second regulating valve, the steam circuit control valve and the power generation circuit control valve, the nuclear power generation steam supply system can simultaneously realize multiple purposes such as sodium-cooled fast reactor power generation and manufacturing industrial high-temperature steam. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Shown is a schematic diagram of a nuclear power generation steam supply system provided in one embodiment of the present application.

[0020] Figure 2 Shown is a schematic diagram of a peak-shaving response curve for molten salt energy storage peak-shaving in a nuclear power generation steam supply system provided in one embodiment of the present application.

[0021] In the figure: 1. Sodium-cooled fast reactor; 2. Intermediate heat exchanger; 3. Secondary circuit sodium pump; 4. Sodium-molten salt heat exchanger; 5. Low-temperature molten salt delivery pump; 6. Solar thermal energy storage system; 7. First regulating valve; 8. Low-temperature molten salt tank; 9. High-temperature molten salt tank; 10. Second regulating valve; 11. High-temperature molten salt delivery pump; 12. Molten salt-water heat exchanger; 13. Steam circuit control valve; 14. Power generation circuit control valve; 15. Superheater; 16. Main feed water pump; 17. Steam turbine generator; 18. Check valve; 19. Steam user; 20. Condenser; 21. Main transformer; 22. Grid user; 23. Energy storage transformer; 24. Supercapacitor; 25. Battery. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0023] At least one embodiment of the present application provides a nuclear power generation steam supply system, referring to Figure 1The nuclear power generation steam supply system includes a sodium-cooled fast reactor 1, an intermediate heat exchanger 2, a secondary circuit sodium pump 3, a sodium-molten salt heat exchanger 4, a low-temperature molten salt delivery pump 5, a first regulating valve 7, a low-temperature molten salt tank 8, a high-temperature molten salt tank 9, a second regulating valve 10, a high-temperature molten salt delivery pump 11, a molten salt-water heat exchanger 12, a steam circuit control valve 13, a power generation circuit control valve 14, a superheater 15, a main feed water pump 16, a steam turbine generator 17, a check valve 18 and a condenser 20. The intermediate heat exchanger 2 is immersed in the sodium pool of the sodium-cooled fast reactor 1. The secondary circuit sodium pump 3 is connected in series between the outlet end of the intermediate heat exchanger 2 and the inlet end of the sodium side of the sodium-molten salt heat exchanger 4. The inlet end of the intermediate heat exchanger 2 is connected to the outlet end of the sodium side of the sodium-molten salt heat exchanger 4. The outlet end of the molten salt fluid side of the sodium-molten salt heat exchanger 4 is connected in series with the high-temperature molten salt tank 9, the second regulating valve 10, the high-temperature molten salt delivery pump 11 and the inlet end of the molten salt fluid side of the molten salt-water heat exchanger 12. The inlet end of the molten salt fluid side of the sodium-molten salt heat exchanger 4 is connected in series with the low-temperature molten salt delivery pump 5, the first regulating valve 7, the low-temperature molten salt tank 8 and the outlet end of the molten salt fluid side of the molten salt-water heat exchanger 12. The outlet end of the water side of the molten salt-water heat exchanger 12 is connected in series with the power generation circuit control valve 14, the superheater 15, the steam turbine generator 17, the check valve 18 and the steam user 19. One end of the steam circuit control valve 13 is connected between the outlet end of the water side of the molten salt-water heat exchanger 12 and the power generation circuit control valve 14, and the other end of the steam circuit control valve 13 is connected to the pipeline between the check valve 18 and the steam user 19. The inlet end of the water side of the molten salt-water heat exchanger 12 is connected in series with the main feed water pump 16 and the condenser 20 in sequence, and then connected to the pipeline between the steam turbine generator 17 and the check valve 18.

[0024] It should be noted that the intermediate heat exchanger 2, the secondary circuit sodium pump 3 and the sodium side of the sodium-molten salt heat exchanger 4 together constitute the secondary circuit; the molten salt fluid side of the sodium-molten salt heat exchanger 4, the low-temperature molten salt delivery pump 5, the first regulating valve 7, the low-temperature molten salt tank 8, the high-temperature molten salt tank 9, the second regulating valve 10, the high-temperature molten salt delivery pump 11 and the molten salt fluid side of the molten salt-water heat exchanger 12 constitute the third circuit; the water side of the molten salt-water heat exchanger 12, the steam circuit control valve 13, the power generation circuit control valve 14, the superheater 15, the main feed water pump 16, the steam turbine generator 17, the check valve 18, the steam user 19 and the condenser 20 constitute the fourth circuit.

[0025] According to the technical solution provided in the embodiment of the present application, by designing the sodium-molten salt heat exchanger 4, the low-temperature molten salt tank 8, the high-temperature molten salt tank 9 and other structures and their connection relationships in the nuclear power generation steam supply system, the nuclear power generation steam supply system adopts a sodium-sodium-molten salt-water four-circuit design. Compared with the existing fast reactor with a sodium-sodium-water three-circuit design (the possibility of sodium-water reaction has not been eliminated), the nuclear power generation steam supply system can effectively ensure the isolation of sodium from molten salt and water, and avoid sodium-water and other reactions. In addition, by controlling the power of the low-temperature molten salt delivery pump 5 and the high-temperature molten salt delivery pump 11 and the opening of the steam circuit control valve 13, the steam amount to the steam turbine generator 17 is adjusted, thereby controlling the power generation power of the steam turbine generator 17, so that the nuclear power generation steam supply system has good frequency modulation and peak regulation capabilities. In addition, by controlling the opening and closing of the first regulating valve 7, the second regulating valve 10, the steam circuit control valve 13 and the power generation circuit control valve 14, the nuclear power generation steam supply system can simultaneously realize sodium-cooled fast reactor power generation, manufacture industrial high-temperature steam and other multiple purposes.

[0026] In at least one embodiment of the present application, the nuclear power generation steam supply system also includes a photothermal energy storage system 6. The photothermal energy storage system 6 is arranged on the outside of the molten salt pipeline between the outlet end of the molten salt fluid side of the sodium-molten salt heat exchanger 4 and the high-temperature molten salt tank 9. In the photothermal energy storage mode, the sodium-cooled fast reactor 1 is maintained at full power, the sodium pump 3 and the high-temperature molten salt delivery pump 11 are operated at rated power, the photothermal energy storage system 6 is used to heat the molten salt pipeline, and the low-temperature molten salt delivery pump 5 is operated at high power. In this way, in the photothermal energy storage mode, the liquid level of the high-temperature molten salt tank 9 rises, and the liquid level of the low-temperature molten salt tank 8 drops. By adjusting the amount of high and low temperature molten salt, part of the core nuclear energy and solar energy are converted into molten salt thermal energy for storage.

[0027] It should be noted that the nuclear power generation steam supply system can adopt a single power generation mode, a high-temperature industrial steam supply mode or a solar thermal energy storage mode, or a combination of multiple modes, which is not specifically limited in the present embodiment. The solar thermal energy storage system 6 can be referred to as an energy storage system.

[0028] In at least one embodiment of the present application, the photothermal energy storage system 6 adopts a linear Fresnel concentrator system. In this way, the advantages of high-energy concentrating and thermal energy conversion of the linear Fresnel concentrator system are utilized to significantly improve the energy conversion efficiency.

[0029] In at least one embodiment of the present application, the sodium-molten salt heat exchanger 4 adopts a double-layer tube design, and an inert gas is used between the double-layer tubes. The hot medium (such as sodium) flows inside the double-layer tube, and the cold medium (such as molten salt) flows on the double-layer tube shell side. In this way, the heat exchange function is guaranteed, and the possibility of sodium-molten salt contact is further avoided. In addition, by setting the hot medium (such as sodium) to flow inside the double-layer tube, and the cold medium (such as molten salt) to flow on the double-layer tube shell side, the reaction of sodium with molten salt and water can be effectively avoided, which ensures the heat exchange efficiency while improving the inherent safety of the system.

[0030] In at least one embodiment of the present application, the nuclear power generation steam supply system further includes a main transformer 21, an energy storage transformer 23, a super capacitor 24 and a nuclear-grade battery pack 25. The power generation outlet of the steam turbine generator 17 is connected in series with the main transformer 21 and the grid user 22 in sequence. The super capacitor 24 and the energy storage transformer 23 are connected in series in sequence and in parallel with the connecting pipe between the power generation outlet of the steam turbine generator 17 and the main transformer 21. The super capacitor 24 is connected to the nuclear-grade battery pack 25 for timing charging and discharging of the nuclear-grade battery pack 25.

[0031] The above embodiment utilizes the main transformer 21, the energy storage transformer 23, the super capacitor 24 and the nuclear-grade battery pack 25 to form a molten salt energy storage circuit, realizes the switching between sodium-cooled fast reactor power generation and the production of high-temperature industrial steam to achieve peak load regulation of the unit, which can save the power plant nearly 20 million yuan in peak load penalty fees each year. At the same time, it can also participate in peak load regulation and enjoy the peak load electricity price, thereby generating additional economic benefits. In addition, the power generation outlet of the steam turbine generator 17 is synchronously connected to the super capacitor 24 and the nuclear-grade battery pack 25 for charging. Through the flow regulation of the molten salt energy storage circuit, the nuclear power generation steam supply system can achieve power generation, industrial steam production and peak load regulation without adjusting the reactor power. The combination of the super capacitor 24 and the nuclear-grade battery pack 25 can be used for frequency regulation and peak load regulation, and can also be used as an emergency power supply system in the plant. The existing nuclear power units that have been put into production do not have frequency regulation and peak load regulation capabilities. The nuclear power generation steam supply system of the above embodiment of the present application can simultaneously achieve sodium-cooled fast reactor power generation, high-temperature industrial steam production and other purposes (see the peak load response curve schematic diagram). Figure 2 ).

[0032] At the same time, the above embodiment realizes the full combination of supercapacitor energy storage technology and the emergency power supply in the fast reactor power plant, replacing the relevant sub-items and equipment such as emergency and reliable diesel generator sets, and greatly reducing the investment in the power plant (for example, saving more than 1 billion yuan of investment) while meeting the energy storage and realizing the secondary frequency regulation function, ensuring the safety and reliability of the power supply, and greatly improving the economy and safety of the fast reactor power plant. At the same time, the emergency and reliable diesel engine sub-items and equipment of the power plant can be eliminated, as well as a large amount of manpower and material costs in the operation stage.

[0033] At least one embodiment of the present application also provides a method for using a nuclear power generation steam supply system, which is executed using the nuclear power generation steam supply system in the above embodiment. In all modes, the sodium-cooled fast reactor 1 operates at full power. The low-temperature molten salt delivery pump 5 and the high-temperature molten salt delivery pump 11 are variable frequency pumps, and their operating conditions are set with low power, rated power and high power operating modes. The nuclear power generation steam supply system has a power generation mode and a high-temperature industrial steam supply mode. The method for using the nuclear power generation steam supply system includes the following steps.

[0034] S100: When the nuclear power generation steam supply system is in the power generation mode, the first regulating valve 7, the second regulating valve 10 and the power generation circuit control valve 14 are opened, the steam circuit control valve 13 is closed, and the low-temperature molten salt delivery pump 5 and the high-temperature molten salt delivery pump 11 are operated at rated power. At this time, the liquid levels of the high-temperature molten salt tank 9 and the low-temperature molten salt tank 8 remain unchanged. The condensate is transported by the main feed water pump 16 through the molten salt-water heat exchanger 12 for heat exchange, and then passes through the superheater 15 to become saturated steam, and finally generates electricity through the steam turbine generator 17, and the exhaust steam of the steam turbine in the steam turbine generator 17 is transported to the steam user 19.

[0035] S200: When the nuclear power generation steam supply system is in the high-temperature industrial steam supply mode, the first regulating valve 7, the second regulating valve 10 and the steam loop control valve 13 are opened, the power generation loop control valve 14 is closed, the low-temperature molten salt delivery pump 5 and the high-temperature molten salt delivery pump 11 are operated at rated power, and the liquid levels of the high-temperature molten salt tank 9 and the low-temperature molten salt tank 8 remain unchanged. The condensate is transported by the main feed water pump 16 through the molten salt-water heat exchanger 12 for heat exchange, and the generated high-temperature industrial steam is directly transported to the steam user 19.

[0036] It should be noted that low power and high power can be set according to the frequency and peak regulation requirements. Low power is the pump power that is lower than the rated power calibrated according to the operation of the energy storage system. Rated power is the rated pump power when the energy storage system is not put into use. High power is the pump power that is higher than the rated power calibrated according to the operation of the energy storage system.

[0037] In at least one embodiment of the present application, the nuclear power generation steam supply system also has a primary frequency regulation and peak regulation mode. The method for using the nuclear power generation steam supply system also includes S300.

[0038] S300: When the nuclear power generation steam supply system is in the primary frequency regulation and peak regulation mode, mode 1 or mode 2 is used when the power is reduced, and mode 3 is used when the power is increased.

[0039] Mode 1: The secondary circuit sodium pump 3 operates at full power, the low-temperature molten salt delivery pump 5 operates at rated power, the high-temperature molten salt delivery pump 11 operates at low power, and the main feed water pump 16 operates at low power.

[0040] Mode 2: while starting the power generation mode of the nuclear power generation steam supply system, the high-temperature industrial steam supply mode of the nuclear power generation steam supply system is also started, and the amount of industrial steam supply is controlled by the opening of the steam loop control valve 13.

[0041] Mode three: the secondary circuit sodium pump 3 operates at full power, the low-temperature molten salt delivery pump 5 maintains rated power operation, and the high-temperature molten salt delivery pump 11 and the main feed water pump 16 operate at high power.

[0042] In the above embodiment, in the mode 1, by setting the secondary circuit sodium pump 3 to run at full power, the secondary circuit sodium pump 3 can be used to continuously take out the heat of the sodium-cooled fast reactor 1, and by setting the high-temperature molten salt delivery pump 11 to run at low power, the high-temperature molten salt delivery pump 11 can achieve a decrease in speed and flow rate, and by setting the main feedwater pump 16 to run at low power, the total amount of steam can be reduced, and finally the output power of the steam turbine generator 17 can be reduced, thereby realizing the peak load regulation of the unit. At this time, the liquid level of the high-temperature molten salt tank 9 will rise, and the liquid level of the low-temperature molten salt tank 8 will continue to decrease. By adjusting the high and low temperature molten salt reserves, the excess energy generated by the core is stored.

[0043] In mode two, by synchronously starting the power generation mode and high-temperature industrial steam supply mode of the nuclear power generation steam supply system, the opening of the steam loop control valve 13 is used to control the amount of industrial steam supply, thereby reducing the power generation power of the steam turbine generator 17 and achieving peak load regulation of the unit.

[0044] In mode three, by setting the secondary sodium pump 3 to run at full power, the secondary sodium pump 3 can be used to continuously remove the heat of the sodium-cooled fast reactor 1, and by setting the low-temperature molten salt delivery pump 5 to maintain rated power operation, the high-temperature molten salt delivery pump 11 and the main feed water pump 16 can run at high power, which can increase the speed of the high-temperature molten salt delivery pump 11, increase the flow rate, increase the total amount of steam, and increase the output power of the steam turbine generator 17, so as to achieve the peak load regulation of the unit. At this time, the liquid level of the high-temperature molten salt tank 9 will decrease, and the liquid level of the low-temperature molten salt tank 8 will continue to increase. By adjusting the reserves of high and low temperature molten salt, the molten salt energy storage will be released, the power generation power of the steam turbine generator 17 will be increased, and the power grid access power of the power station will be increased.

[0045] In at least one embodiment of the present application, the method for using the nuclear power generation steam supply system also includes S400 and S500.

[0046] S400: When the power is reduced, the power generation mode of the nuclear power generation steam supply system is kept unchanged, and the super capacitor 24 and the nuclear-grade battery group 25 are synchronously connected to the power generation outlet of the steam turbine generator 17 for charging.

[0047] S500: When the power is increased, the power generation mode of the nuclear power generation steam supply system is kept unchanged, and the super capacitor 24 and the nuclear-grade battery group 25 are synchronously connected to the grid-connected end of the power station for discharge.

[0048] Thus, by executing step S400, the grid-connected power of the power plant can be effectively reduced, and the unit frequency regulation can be quickly realized. By executing step S500, the grid-connected power of the fast reactor power plant can be increased, and the unit secondary frequency regulation can be realized.

[0049] It should be noted that the combination of the various technical features in the embodiments of the present application is not limited to the combination described in the embodiments of the present application or the combination described in the specific embodiments, and all technical features described in the present application can be freely combined or combined in any way unless there is a contradiction between them.

[0050] As shown in this application and claims, unless the context clearly indicates an exception, the words "a", "an" and / or "the" do not refer to the singular and may also include the plural. Generally speaking, the term "comprising" only indicates that the steps and elements that have been clearly identified are included, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0051] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A nuclear power generation steam supply system, characterized in that: It includes a sodium-cooled fast reactor, an intermediate heat exchanger, a secondary circuit sodium pump, a sodium-molten salt heat exchanger, a low-temperature molten salt delivery pump, a first regulating valve, a low-temperature molten salt tank, a high-temperature molten salt tank, a second regulating valve, a high-temperature molten salt delivery pump, a molten salt-water heat exchanger, a steam circuit control valve, a power generation circuit control valve, a superheater, a main feed water pump, a steam turbine generator, a check valve and a condenser. Among them, the intermediate heat exchanger is immersed in the sodium pool of the sodium-cooled fast reactor, the secondary circuit sodium pump is connected in series between the outlet end of the intermediate heat exchanger and the inlet end of the sodium side of the sodium-molten salt heat exchanger, the inlet end of the intermediate heat exchanger is connected to the outlet end of the sodium side of the sodium-molten salt heat exchanger, the outlet end of the molten salt fluid side of the sodium-molten salt heat exchanger is connected in series with the high-temperature molten salt tank, the second regulating valve, the high-temperature molten salt delivery pump and the inlet end of the molten salt fluid side of the molten salt-water heat exchanger in sequence, the inlet end of the molten salt fluid side of the sodium-molten salt heat exchanger is connected in series with the low-temperature molten salt delivery pump, the first regulating valve, the low-temperature molten salt The tank and the outlet end of the molten salt fluid side of the molten salt-water heat exchanger are connected in series, the outlet end of the water side of the molten salt-water heat exchanger is connected to the power generation circuit control valve, the superheater, the steam turbine generator, the check valve and the steam user in sequence, one end of the steam circuit control valve is connected between the outlet end of the water side of the molten salt-water heat exchanger and the power generation circuit control valve, the other end of the steam circuit control valve is connected to the pipeline between the check valve and the steam user, and the inlet end of the water side of the molten salt-water heat exchanger is connected in series with the main feed water pump and the condenser in sequence, and then connected to the pipeline between the steam turbine generator and the check valve.

2. A nuclear power generation steam supply system according to claim 1, characterized in that: It also includes a solar thermal energy storage system. The solar thermal energy storage system is installed outside the molten salt pipeline between the outlet of the molten salt fluid side of the sodium-molten salt heat exchanger and the high-temperature molten salt tank. In the solar thermal energy storage mode, the sodium-cooled fast stack is maintained at full power, the sodium pump and high-temperature molten salt delivery pump are operated at rated power, the solar thermal energy storage system is used to heat the molten salt pipeline, and the low-temperature molten salt delivery pump is operated at high power.

3. A nuclear power generation steam supply system according to claim 2, characterized in that: The solar thermal energy storage system adopts a linear Fresnel concentrating system.

4. A nuclear power generation steam supply system according to claim 1, characterized in that: The sodium-molten salt heat exchanger adopts a double-layer tube design, with inert gas used between the double-layer tubes, hot medium flowing on the inner side of the double-layer tube, and cold medium flowing on the double-layer tube shell side.

5. A nuclear power generation steam supply system according to any one of claims 1 to 4, characterized in that: It also includes main transformer, energy storage transformer, super capacitor and nuclear grade battery pack. The power generation outlet of the steam turbine generator is connected in series with the main transformer and the grid user in sequence, and the super capacitor and the energy storage transformer are connected in series in sequence and in parallel with the connecting pipeline between the power generation outlet of the steam turbine generator and the main transformer; The supercapacitor is connected to the nuclear-grade battery pack and is used for performing timed charging and discharging of the nuclear-grade battery pack.

6. A method for using a nuclear power generation steam supply system, characterized in that: The method is implemented by using a nuclear power generation steam supply system as claimed in any one of claims 1 to 5, wherein in all modes, the sodium-cooled fast reactor in the nuclear power generation steam supply system operates at full power, the low-temperature molten salt delivery pump and the high-temperature molten salt delivery pump are variable frequency pumps, and their operating conditions are set to low power, rated power and high power operating modes, and the nuclear power generation steam supply system has a power generation mode and a high-temperature industrial steam supply mode, wherein the use method of the nuclear power generation steam supply system includes: When the nuclear power generation steam supply system is in power generation mode, the first regulating valve, the second regulating valve and the power generation circuit control valve are opened, the steam circuit control valve is closed, and the low-temperature molten salt delivery pump and the high-temperature molten salt delivery pump are operated at rated power. At this time, the liquid levels of the high-temperature molten salt tank and the low-temperature molten salt tank remain unchanged; the condensate is transported by the main feed water pump through the molten salt-water heat exchanger for heat exchange, and then passes through the superheater to become saturated steam, and finally generates electricity through the steam turbine generator, and the exhaust steam of the steam turbine in the steam turbine generator is transported to the steam user; When the nuclear power generation steam supply system is in the high-temperature industrial steam supply mode, open the first regulating valve, the second regulating valve and the steam loop control valve, close the power generation loop control valve, the low-temperature molten salt delivery pump and the high-temperature molten salt delivery pump operate at rated power, the liquid levels of the high-temperature molten salt tank and the low-temperature molten salt tank remain unchanged, the condensate is transported by the main feed water pump through the molten salt-water heat exchanger for heat exchange, and the generated high-temperature industrial steam is directly transported to the steam users.

7. The method for using a nuclear power generation steam supply system according to claim 6, characterized in that: The nuclear power generation steam supply system also has primary frequency regulation and peak regulation modes. The use of the nuclear power generation steam supply system also includes: When the nuclear power generation steam supply system is in primary frequency regulation and peak regulation mode, mode 1 or mode 2 is used when the power is reduced, and mode 3 is used when the power is increased. Mode 1: The secondary circuit sodium pump runs at full power, the low-temperature molten salt delivery pump runs at rated power, the high-temperature molten salt delivery pump runs at low power, and the main feed water pump runs at low power; Mode 2: When the power generation mode of the nuclear power generation steam supply system is turned on, the high-temperature industrial steam supply mode of the nuclear power generation steam supply system is turned on simultaneously, and the amount of industrial steam supply is controlled by the opening of the steam loop control valve; Mode 3: The secondary circuit sodium pump operates at full power, the low-temperature molten salt delivery pump maintains rated power operation, and the high-temperature molten salt delivery pump and the main feed water pump operate at high power.

8. The method for using a nuclear power generation steam supply system according to claim 6, characterized in that: Also includes: When the power is reduced, the power generation mode of the nuclear power generation steam supply system is kept unchanged, and the supercapacitor and nuclear-grade battery group are synchronously connected to the power generation outlet of the steam turbine generator for charging; When the power is increased, the power generation mode of the nuclear power generation steam supply system is kept unchanged, and supercapacitors and nuclear-grade battery packs are synchronously connected to the grid-connected end of the power station for discharge.

Images