Molten salt-based generator set for transforming thermal power into nuclear power
By introducing molten salt components and heat exchange components into thermal power units and adjusting steam parameters, the thermal mismatch between thermal power units and nuclear power reactors was resolved, enabling efficient utilization of existing assets in nuclear power retrofitting and reducing retrofitting costs.
Patent Information
- Application Number
- CN202520346141.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-28
- Publication Date
- 2026-02-10
- Estimated Expiration
- 2035-02-28
AI Technical Summary
During the process of converting thermal power units into nuclear power units, there is a problem of mismatch between the original thermal power unit's thermal system and the steam parameters of the nuclear power reactor.
Molten salt assemblies are used to store the steam heat from the nuclear island steam generator in molten salt. Steam parameters are adjusted by controlling the temperature and flow rate of the molten salt, as well as the pressure and flow rate of the feedwater pipeline, in order to achieve thermal system matching between the nuclear power reactor and the thermal power unit.
While maintaining the original steam turbine generator system of the thermal power unit unchanged, the matching problem of the thermal system was solved, the existing assets were utilized to the maximum extent, and the renovation investment was reduced.
Smart Images
Figure CN223894220U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the technical field of thermal power transformation, especially relates to a generator unit of thermal power transformation into nuclear power based on fused salt. BACKGROUND
[0002] How to realize the orderly reduction of thermal power on the basis of safe and reliable replacement of new energy is the core problem of new power system. The thermal power reserves in China's power system are large, the proportion is high, and the carbon emissions are high. The situation of carbon emission reduction of thermal power is severe.
[0003] At present, in addition to early retirement and reducing direct emissions through carbon capture systems, using nuclear power and other low-carbon technologies to transform thermal power units is also an explorable path. From the functional point of view, nuclear power and thermal power can be used as base load power supply. From the resource utilization rate point of view, thermal power is rigidly withdrawn in the case of long remaining life, and the overall cost of decommissioning and removing existing thermal power plants is high. Therefore, the transformation of thermal power plants into nuclear power can utilize the existing power grid access system, water source, land, power transmission facilities and part of the process equipment and infrastructure resources of the existing thermal power plant to reduce the overall cost of the power plant.
[0004] However, in the process of transforming the thermal power unit into nuclear power, there is a problem of mismatching the steam parameters of the original thermal power unit thermal system and the steam parameters generated by the nuclear power reactor. Therefore, it is necessary to study a method for transforming the thermal power unit into nuclear power to solve the problem of matching the thermal systems of the original thermal power unit and the nuclear power reactor while maintaining the basic unchanged condition of the original thermal power unit steam turbine generator system. UTILITY MODEL CONTENTS
[0005] The utility model embodiment provides a kind of generator unit of thermal power transformation into nuclear power based on fused salt, can solve the problem of matching the thermal systems of original thermal power unit and nuclear power reactor.
[0006] The utility model embodiment provides a kind of generator unit of thermal power transformation into nuclear power based on fused salt, including nuclear island steam generator, steam fused salt heat exchanger, fused salt component, heat exchange component, water supply pipeline, steam turbine and generator, the steam fused salt heat exchanger is connected with the nuclear island steam generator and the fused salt component respectively, for the steam heat storage of the nuclear island steam generator into the fused salt of the fused salt component, the heat exchange component is connected with the fused salt component and the water supply pipeline respectively, the steam turbine is connected with the heat exchange component by steam pipeline, the steam turbine is connected with the generator, by controlling the temperature and flow of fused salt in the fused salt component and the pressure and flow of water supply in the water supply pipeline, to control the steam parameter that the steam pipeline supplies to the steam turbine, to realize the thermal system matching of nuclear power reactor and thermal power unit.
[0007] Compared with related technologies, this utility model has at least the following advantages:
[0008] According to the embodiments of this utility model, a generator set for converting thermal power to nuclear power based on molten salt is provided. By setting up a molten salt assembly, the steam heat of the nuclear island steam generator is stored in the molten salt of the molten salt assembly. The steam parameters supplied to the steam turbine by the steam pipeline are controlled by controlling the temperature and flow rate of the molten salt in the molten salt assembly and the pressure and flow rate of the feed water in the feed water pipeline, so as to achieve thermal system matching between the nuclear power reactor and the thermal power unit. Attached Figure Description
[0009] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0010] Figure 1 A schematic diagram of a generator unit for converting thermal power into nuclear power based on molten salt, provided as an embodiment of this utility model.
[0011] Figure label:
[0012] 1-Nuclear island steam generator; 2-Steam molten salt heat exchanger; 3-Feedwater pipeline; 4-Steam turbine; 5-Generator; 6-Hot brine tank; 7-Hot brine pump; 8-Cold brine tank; 9-Cold brine pump; 10-First molten salt pipeline; 11-Second molten salt pipeline; 12-Molten salt electric heater; 13-Superheater; 14-Evaporator; 15-Preheater; 16-Reheater; 17-Third molten salt pipeline; 18-Main steam pipeline of thermal power plant; 19-Cold section pipeline of thermal power plant; 20-Hot section pipeline of thermal power plant; 21-Extraction steam feedwater heat exchanger; 22-Extraction steam pipeline; 23-Feedwater pump of thermal power plant; 24-Drainage feedwater heat exchanger; 25-Nuclear island feedwater pump. Detailed Implementation
[0013] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.
[0014] Please see Figure 1This utility model embodiment provides a generator set for converting thermal power to nuclear power based on molten salt, including a nuclear island steam generator 1, a steam molten salt heat exchanger 2, a molten salt assembly, a heat exchange assembly, a feedwater pipeline 3, a steam turbine 4, and a generator 5. The steam molten salt heat exchanger 2 is connected to the nuclear island steam generator 1 and the molten salt assembly, respectively, and is used to store the steam heat of the nuclear island steam generator 1 in the molten salt of the molten salt assembly. The heat exchange assembly is connected to the molten salt assembly and the feedwater pipeline 3, respectively. The steam turbine 4 is connected to the heat exchange assembly through a steam pipeline and to the generator 5. The steam parameters supplied to the steam turbine 4 by the steam pipeline are controlled by controlling the temperature and flow rate of the molten salt in the molten salt assembly and the pressure and flow rate of the feedwater in the feedwater pipeline 3, so as to achieve thermal system matching between the nuclear power reactor and the thermal power unit.
[0015] In this embodiment, by setting up a molten salt assembly, the steam heat of the nuclear island steam generator 1 is stored in the molten salt of the molten salt assembly. The steam parameters supplied by the steam pipeline to the steam turbine 4 are controlled by controlling the temperature and flow rate of the molten salt in the molten salt assembly and the pressure and flow rate of the feed water in the feed water pipeline 3, so as to achieve thermal system matching between the nuclear power reactor and the thermal power unit.
[0016] It should be noted that the aforementioned combined generating units refer to the conversion of existing thermal power plants using nuclear power. A nuclear power plant mainly consists of a nuclear island reactor system, a conventional island turbine generator system, and auxiliary systems. A thermal power plant mainly consists of a boiler system, a main plant turbine generator system, and auxiliary systems. The nuclear power conversion of a thermal power unit involves replacing the boiler system with the nuclear island reactor system to provide heat to the power plant, while reusing other parts of the original thermal power unit, such as the turbine generator system, as much as possible. To address the thermal system mismatch problem that exists during the nuclear power conversion of thermal power units, a method based on a molten salt system is proposed to replace thermal power units with nuclear power. This method primarily uses a high-temperature gas-cooled reactor nuclear power plant reactor to replace the boiler in the thermal power plant, while the original thermal power unit's turbine generator system remains unchanged.
[0017] In one embodiment of this utility model, the molten salt assembly includes a hot salt tank 6, a hot salt pump 7, a cold salt tank 8, and a cold salt pump 9. The hot salt pump 7 is disposed in the hot salt tank 6, and the cold salt pump 9 is disposed in the cold salt tank 8. The hot salt tank 6 and the cold salt tank 8 are connected by a first molten salt pipe 10 and a second molten salt pipe 11. Cold molten salt enters the hot salt tank 6 from the cold salt tank 8 through the first molten salt pipe 10, and hot molten salt enters the cold salt tank 8 from the hot salt tank 6 through the second molten salt pipe 11. A steam molten salt heat exchanger 2 is disposed on the first molten salt pipe 10, and a heat exchange assembly is disposed on the second molten salt pipe 11.
[0018] In this embodiment, by setting up a hot salt tank 6, a hot salt pump 7, a cold salt tank 8, and a cold salt pump 9, the cold molten salt can absorb the steam heat from the nuclear island steam generator 1, and the heat from the hot molten salt can be used to heat the feedwater in the feedwater pipe 3 to form steam to drive the steam turbine 4.
[0019] In one embodiment of the present invention, the molten salt assembly further includes a molten salt electric heater 12, which is disposed on the first molten salt pipeline 10 and located between the steam molten salt heat exchanger 2 and the hot salt tank 6.
[0020] In this embodiment, by setting up a molten salt electric heater 12, the temperature of the molten salt in the hot salt tank 6 can be increased, thereby meeting the temperature requirements of the main steam and reheat steam of the original thermal power unit turbine.
[0021] In one embodiment of the present invention, the heat exchange assembly includes a superheater 13, an evaporator 14 and a preheater 15 arranged sequentially along the flow direction of the hot molten salt, and the preheater 15, the evaporator 14 and the superheater 13 are arranged sequentially along the flow direction of the feed water, and the outlet of the superheater 13 is connected to the steam turbine 4.
[0022] In one embodiment of the present invention, the heat exchange assembly further includes a reheater 16, and the second molten salt pipe 11 is connected in parallel with a third molten salt pipe 17. The reheater 16 is disposed on the third molten salt pipe 17. The steam turbine 4 includes a high-pressure cylinder and an intermediate-pressure cylinder. The outlet of the superheater 13 is connected to the inlet of the high-pressure cylinder through the thermal power main steam pipe 18. The outlet of the high-pressure cylinder is connected to the inlet of the reheater 16 through the thermal power cold section pipe 19. The outlet of the reheater 16 is connected to the inlet of the intermediate-pressure cylinder through the thermal power hot section pipe 20.
[0023] In one embodiment of the present invention, the inlet of the third molten salt pipe 17 is located at the inlet of the superheater 13, and the outlet of the third molten salt pipe 17 is located between the superheater 13 and the evaporator 14.
[0024] In one embodiment of this utility model, a steam extraction feedwater heat exchanger 21 is also included. One end of the steam extraction feedwater heat exchanger 21 is connected to a high-pressure cylinder through a steam extraction pipe 22, and the other end is connected to a feedwater pipe 3. A thermal power feedwater pump 23 is installed on the feedwater pipe 3.
[0025] In one embodiment of this utility model, a condensate feed water heat exchanger 24 is also provided on the water supply pipe 3. The condensate feed water heat exchanger 24 is connected to the steam molten salt heat exchanger 2 and the nuclear island steam generator 1 through pipes. A nuclear island feed water pump 25 is provided on the pipe between the condensate feed water heat exchanger 24 and the nuclear island steam generator 1.
[0026] The process and purpose of the above technical solution are described below.
[0027] 1) The process of steam heating molten salt in the nuclear island
[0028] High-temperature steam from the outlet of the nuclear island steam generator 1 enters the steam-molten salt heat exchanger 2, where it heats the molten salt and becomes condensate. A condensate feedwater heat exchanger 24 is installed downstream of the feedwater in the original thermal power plant extraction steam feedwater heat exchanger 21. Condensate from the outlet of the steam-molten salt heat exchanger 3 enters the condensate feedwater heat exchanger 24, where it heats the feedwater. After being cooled to a certain temperature, it is pressurized by the nuclear island feedwater pump 25 and enters the nuclear island steam generator 1. Low-temperature molten salt in the cold salt tank 8 is pressurized by the cold salt pump 9 and enters the steam-molten salt heat exchanger 2, where it is heated by the high-temperature steam from the nuclear island. The molten salt at the outlet of the steam-molten salt heat exchanger 2 enters the molten salt electric heater 12 for further heating to a specified temperature before entering the hot salt tank 6.
[0029] In this process, the nuclear island reactor technology adopts a high-temperature gas-cooled reactor, and the outlet of the nuclear island steam generator 1 is high-temperature and high-pressure steam. High-pressure steam corresponds to a higher steam saturation temperature. Under the condition that the inlet molten salt temperature of the steam molten salt heat exchanger 2 is higher than the freezing point without solidification, the latent heat of steam can be fully utilized to heat the molten salt and increase the outlet molten salt temperature of the heat exchanger. Considering the problem of preventing the low-temperature molten salt in the cold salt tank 8 from condensing, the outlet condensate temperature of the steam molten salt heat exchanger 2 is relatively high. A condensate feedwater heat exchanger 24 is installed on the original thermal power unit feedwater pipeline to fully utilize the heat of the condensate to heat the feedwater. While reducing the condensate temperature, the feedwater temperature entering the preheater 15 can be increased to prevent the molten salt at the outlet of the preheater 15 from solidifying.
[0030] 2) Molten salt releases heat to generate steam.
[0031] Feedwater from the boiler inlet feedwater pipe 3 of the original thermal power unit enters the condensate feedwater heat exchanger 24 and is heated before entering the steam generation system. It then passes through the preheater 15, evaporator 14, and superheater 13, where it is heated by molten salt into high-temperature superheated steam, which enters the original thermal power main steam pipe 18. Low-temperature reheated steam from the original thermal power cold section pipe 19 enters the reheater 16 and is heated by molten salt into high-temperature reheated steam before entering the original thermal power hot section pipe 20. High-temperature molten salt in the hot salt tank 6 is pressurized by the hot salt pump 7 and split into two streams: one enters the superheater 13, and the other enters the reheater 16. The two streams of molten salt are cooled by steam and merged into one stream, which then enters the evaporator 14 and preheater 15, finally being cooled into low-temperature molten salt and entering the cold salt tank 8.
[0032] 3) Steam turbine power generation
[0033] The high-temperature, high-pressure main steam generated by the heat release of molten salt enters the original thermal power plant's main steam pipeline 18, and then enters the high-pressure cylinder to drive the turbine for power generation. The exhaust steam from the high-pressure cylinder enters the reheater 16 via the original thermal power plant's cold section pipeline 19, where it is heated into high-temperature reheat steam before entering the original thermal power plant's hot section pipeline 20, and then enters the intermediate-pressure cylinder to drive the turbine for power generation. The outlet feedwater from the original thermal power plant's feedwater pump 23 passes sequentially through the extraction steam feedwater heat exchanger 21 and the condensate feedwater heat exchanger 24 to generate high-temperature, high-pressure steam. When the condensate feedwater heat exchanger 24 is in operation, the extraction steam feedwater heat exchanger 21 is completely or partially shut down, which reduces the amount of steam extracted from the turbine and increases the turbine's power generation capacity.
[0034] In summary, the above technical solution stores the steam heat of the secondary loop in the nuclear island in molten salt, and raises the temperature of the high-temperature molten salt through the molten salt electric heater 12. The molten salt assembly and heat exchange assembly can heat the feedwater and low-temperature reheat steam of the original thermal power unit, generating main steam and high-temperature reheat steam with the same parameters as the original thermal power unit. This solves the problem of mismatch between the main steam system and reheat steam system parameters of the nuclear power unit and the thermal power unit during the nuclear power conversion process. Through this reasonable method of converting thermal power units into nuclear power units, the original turbine power generation system of the thermal power unit can be maintained unchanged, maximizing the utilization of existing assets and reducing conversion investment.
[0035] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.
[0036] Finally, it should be noted that the above description is only a preferred embodiment of this utility model and is used only to illustrate the technical solution of this utility model, and is not intended to limit the protection scope of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model are included within the protection scope of this utility model.
Claims
1. A generator set for converting thermal power plants into nuclear power plants based on molten salt, characterized in that, The system includes a nuclear island steam generator (1), a steam molten salt heat exchanger (2), a molten salt assembly, a heat exchange assembly, a feedwater pipeline (3), a steam turbine (4), and a generator (5). The steam molten salt heat exchanger (2) is connected to the nuclear island steam generator (1) and the molten salt assembly, respectively, and is used to store the steam heat of the nuclear island steam generator (1) in the molten salt of the molten salt assembly. The heat exchange assembly is connected to the molten salt assembly and the feedwater pipeline (3), respectively. The steam turbine (4) is connected to the heat exchange assembly through a steam pipeline. The steam turbine (4) is connected to the generator (5). The steam parameters supplied by the steam pipeline to the steam turbine (4) are controlled by controlling the temperature and flow rate of the molten salt in the molten salt assembly and the pressure and flow rate of the feedwater in the feedwater pipeline (3), so as to achieve thermal system matching between the nuclear power reactor and the thermal power unit.
2. The generator set for converting thermal power to nuclear power based on molten salt, as described in claim 1, is characterized in that... The molten salt assembly includes a hot salt tank (6), a hot salt pump (7), a cold salt tank (8), and a cold salt pump (9). The hot salt pump (7) is located in the hot salt tank (6), and the cold salt pump (9) is located in the cold salt tank (8). The hot salt tank (6) and the cold salt tank (8) are connected by a first molten salt pipe (10) and a second molten salt pipe (11). Cold molten salt enters the hot salt tank (6) from the cold salt tank (8) through the first molten salt pipe (10), and hot molten salt enters the cold salt tank (8) from the hot salt tank (6) through the second molten salt pipe (11). The steam molten salt heat exchanger (2) is located on the first molten salt pipe (10), and the heat exchange assembly is located on the second molten salt pipe (11).
3. The generator set for converting thermal power to nuclear power based on molten salt, as described in claim 2, is characterized in that... The molten salt assembly also includes a molten salt electric heater (12), which is disposed on the first molten salt pipe (10) and located between the steam molten salt heat exchanger (2) and the hot salt tank (6).
4. The generator set for converting thermal power to nuclear power based on molten salt, as described in claim 3, is characterized in that... The heat exchange assembly includes a superheater (13), an evaporator (14), and a preheater (15) arranged sequentially along the flow direction of the hot molten salt, and the preheater (15), the evaporator (14), and the superheater (13) are arranged sequentially along the flow direction of the feed water, and the outlet of the superheater (13) is connected to the steam turbine (4).
5. The generator set for converting thermal power to nuclear power based on molten salt according to claim 4, characterized in that, The heat exchange assembly also includes a reheater (16), and the second molten salt pipe (11) is connected in parallel with a third molten salt pipe (17). The reheater (16) is disposed on the third molten salt pipe (17). The steam turbine (4) includes a high-pressure cylinder and an intermediate-pressure cylinder. The outlet of the superheater (13) is connected to the inlet of the high-pressure cylinder through the thermal power main steam pipe (18). The outlet of the high-pressure cylinder is connected to the inlet of the reheater (16) through the thermal power cold section pipe (19). The outlet of the reheater (16) is connected to the inlet of the intermediate-pressure cylinder through the thermal power hot section pipe (20).
6. The generator set for converting thermal power to nuclear power based on molten salt, as described in claim 5, is characterized in that... The inlet of the third molten salt pipe (17) is located at the inlet of the superheater (13), and the outlet of the third molten salt pipe (17) is located between the superheater (13) and the evaporator (14).
7. The generator set for converting thermal power to nuclear power based on molten salt, as described in claim 5, is characterized in that... It also includes a steam extraction feedwater heat exchanger (21), one end of which is connected to the high-pressure cylinder through a steam extraction pipe (22), and the other end is connected to the feedwater pipe (3), on which a thermal power feedwater pump (23) is installed.
8. The generator set for converting thermal power to nuclear power based on molten salt according to claim 7, characterized in that, A condensate feed water heat exchanger (24) is also installed on the water supply pipeline (3). The condensate feed water heat exchanger (24) is connected to the steam molten salt heat exchanger (2) and the nuclear island steam generator (1) through pipelines. A nuclear island feed water pump (25) is installed on the pipeline between the condensate feed water heat exchanger (24) and the nuclear island steam generator (1).