A high temperature gas cooled reactor coupled with molten salt heat storage operation system and method

Abstract

The disclosure provides a high-temperature gas cooled reactor and molten salt heat storage coupled operation system and method, the system comprises a molten salt heat storage system and a high-temperature gas cooled reactor secondary circuit system; the molten salt heat storage system comprises a heating system, a heat storage system and a heat exchange system, the heat storage system comprises a main energy storage tank and a backup energy storage tank, when the high-temperature gas cooled reactor is normally operated, if a peak shaving and frequency modulation instruction is received, the molten salt heat storage system is used to complete peak shaving and frequency modulation; in the start-up debugging stage, the heat energy stored in the main energy storage tank is used to heat feed water to generate a first auxiliary steam, when the remaining heat energy stored in the main energy storage tank cannot meet the requirements, a second auxiliary steam is generated by using the high-temperature gas cooled reactor secondary circuit system, if the high-temperature gas cooled reactor secondary circuit system is abnormal, the backup energy storage tank is started, and the heat energy stored in the backup energy storage tank is used to heat feed water through the heat exchange system to generate a third auxiliary steam. According to the system of the disclosure, auxiliary steam can be provided when the auxiliary electric boiler fails, and frequency modulation and peak shaving can be performed.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of power systems, in particular to a high-temperature gas cooled reactor and molten salt heat storage coupled operation system and method. BACKGROUND

[0002] With the continuous advancement of carbon reduction, new energy power generation systems such as photovoltaic and wind power are developing rapidly, and the installed capacity is increasing. However, some problems have also been exposed, that is, new energy power generation systems such as photovoltaic and wind power are greatly affected by weather factors, the power generation is unstable, and the fluctuation is large, which seriously affects the stability and safety of the entire power system. Therefore, in the future high-proportion new energy power grid, nuclear power units will still play an important role in basic load. In recent years, China's nuclear power industry has also developed rapidly. The capacity of the units under construction has ranked first in the world for many years, and in particular, the high-temperature gas cooled reactor demonstration project with the characteristics of the fourth generation nuclear power has also successfully connected to the grid in 2021, marking that China's nuclear power technology has reached a leading position. The high-temperature gas cooled reactor has inherent safety characteristics, that is, it will not cause core melt-down under any circumstances, and has good application prospects in the future in the fields of inland nuclear power promotion, thermal power unit modification, and nuclear energy heating.

[0003] The primary circuit of the high-temperature gas cooled reactor uses helium as the cooling medium and heat exchange medium, and the secondary circuit uses water / water vapor as the heat exchange medium. Among them, during the startup phase or the debugging phase of the unit, the auxiliary electric boiler heats the feed water to provide auxiliary steam for important systems of the unit, such as the shaft seal system, etc. The auxiliary electric boiler is powered by an external 110kV power supply through a high-voltage auxiliary transformer. However, due to the long startup time, large power consumption, low working reliability, and the inability of the reactor power to change quickly of the high-temperature gas cooled reactor auxiliary electric boiler, the unit of the high-temperature gas cooled reactor does not consider the frequency modulation and peak shaving operation mode, and the auxiliary electric boiler is powered by an external 110kV power supply through a high-voltage auxiliary transformer without other power sources, which makes its working reliability low. During the startup and debugging phase, if the external 110kV line fails, the auxiliary electric boiler may stop, causing the unit to lose auxiliary steam and resulting in the shaft seal and other important systems being unable to work normally. SUMMARY

[0004] The present disclosure aims to at least partially solve one of the technical problems in the related art.

[0005] To this end, the present disclosure provides a high-temperature gas cooled reactor and molten salt heat storage coupled operation system and method, the main purpose of which is to provide auxiliary steam when the auxiliary electric boiler fails and to be able to perform frequency modulation and peak shaving.

[0006] According to a first aspect of the present disclosure, a high-temperature gas cooled reactor and molten salt heat storage coupled operation system is provided, comprising a molten salt heat storage system and a high-temperature gas cooled reactor secondary circuit system;

[0007] The molten salt heat storage system comprises a heating system, a heat storage system and a heat exchange system, the heat storage system comprises a main energy storage tank and a backup energy storage tank, the molten salt heat storage system is used for, when a downward adjustment peak shaving and frequency modulation instruction is received during normal operation of the high-temperature gas cooled reactor, heating the molten salt in the heat storage system by using the heating system, so as to complete the peak shaving and frequency modulation; when the high-temperature gas cooled reactor is in a start-up debugging stage, the heat energy stored in the main energy storage tank is used to heat feed water through the heat exchange system to generate first auxiliary steam, when the remaining heat energy stored in the main energy storage tank does not meet the requirement, second auxiliary steam is generated by using the high-temperature gas cooled reactor two-loop system, if the high-temperature gas cooled reactor two-loop system is abnormal, the backup energy storage tank is started, and the heat energy stored in the backup energy storage tank is used to heat feed water through the heat exchange system to generate third auxiliary steam.

[0008] The high-temperature gas cooled reactor two-loop system is connected in parallel with the heat exchange system, and the high-temperature gas cooled reactor two-loop system comprises an auxiliary electric boiler, and the auxiliary electric boiler is used for heating feed water to generate second auxiliary steam during normal operation of the two-loop system.

[0009] In one embodiment of the present disclosure, the remaining heat energy stored in the main energy storage tank does not meet the requirement refers to that the working time supported by the remaining heat energy stored in the main energy storage tank is not more than a preset multiple of the start-up time of the auxiliary electric boiler.

[0010] In one embodiment of the present disclosure, the heating system comprises a preset number of electric heaters, and the preset number is determined according to the peak shaving capacity of the high-temperature gas cooled reactor unit and parameters of the molten salt heat storage system.

[0011] In one embodiment of the present disclosure, the heating system further comprises an intelligent power regulation device and an electric heater control switch, the number of the electric heater control switches is equal to the number of the electric heaters, each electric heater is connected with an electric heater control switch, and the intelligent power regulation device is used for calculation and analysis based on the downward adjustment peak shaving and frequency modulation instruction to control the on-off of each electric heater control switch.

[0012] In one embodiment of the present disclosure, the heat storage system comprises a low-temperature molten salt tank and a high-temperature molten salt tank, and the number of the high-temperature molten salt tank is equal to the number of the electric heaters, and each high-temperature molten salt tank is connected with an electric heater.

[0013] In one embodiment of the present disclosure, the heat storage system further comprises a low-temperature molten salt pump, a low-temperature molten salt flow controller and a low-temperature molten salt control valve, the number of the low-temperature molten salt control valve is equal to the number of the electric heaters, each low-temperature molten salt control valve is connected with a high-temperature molten salt tank through an electric heater, and the low-temperature molten salt tank is connected with the low-temperature molten salt pump, the low-temperature molten salt flow controller and the low-temperature molten salt control valve.

[0014] In one embodiment of the present disclosure, the heat exchange system comprises a heat exchanger, the heat exchanger comprising a molten salt inlet, a molten salt outlet, a feedwater inlet and a steam outlet.

[0015] In one embodiment of the present disclosure, the heat exchange system further comprises a high-temperature molten salt control valve, a check valve, a high-temperature molten salt pump and a high-temperature molten salt flow controller, the high-temperature molten salt tank being connected to the heat exchanger via the high-temperature molten salt control valve, the check valve, the high-temperature molten salt pump and the high-temperature molten salt flow controller.

[0016] In one embodiment of the present disclosure, the heat exchange system further comprises a heat exchanger feedwater flow control valve and a heat exchanger steam flow control valve, the heat exchanger feedwater flow control valve being arranged on a pipeline at the feedwater inlet, and the heat exchanger steam flow control valve being arranged on a pipeline at the steam outlet.

[0017] According to a second aspect of the present disclosure, a high-temperature gas cooled reactor and molten salt heat storage coupled operation method is provided, based on the high-temperature gas cooled reactor and molten salt heat storage coupled operation system of the first aspect of the present disclosure, comprising:

[0018] When the high-temperature gas cooled reactor is in normal operation, if a downward adjustment peak regulation and frequency modulation instruction is received, the heating system of the molten salt heat storage system is controlled to heat the molten salt in the heat storage system, thereby completing peak regulation and frequency modulation;

[0019] When the high-temperature gas cooled reactor is in a start-up and commissioning phase, the main energy storage tank of the heat storage system is started, and the heat energy stored in the main energy storage tank is used to heat feedwater via the heat exchange system to generate a first auxiliary steam;

[0020] When the remaining heat energy stored in the main energy storage tank does not meet the requirements, a second auxiliary steam is generated by using the high-temperature gas cooled reactor two-loop system;

[0021] If the high-temperature gas cooled reactor two-loop system is abnormal, a standby energy storage tank of the heat storage system is started, and the heat energy stored in the standby energy storage tank is used to heat feedwater via the heat exchange system to generate a third auxiliary steam.

[0022] In one or more embodiments of the present disclosure, the coupled operation system comprises a molten salt heat storage system and a high temperature gas cooled reactor secondary circuit system; the molten salt heat storage system comprises a heating system, a heat storage system and a heat exchange system, the heat storage system comprises a main energy storage tank and a backup energy storage tank, and the molten salt heat storage system is used to heat the molten salt in the heat storage system by the heating system to complete peak shaving and frequency modulation when receiving a downward adjustment peak shaving and frequency modulation instruction during normal operation of the high temperature gas cooled reactor; during the start-up and commissioning stage of the high temperature gas cooled reactor, the first auxiliary steam is generated by heating feedwater by the heat exchange system using the heat energy stored in the main energy storage tank, the second auxiliary steam is generated by the high temperature gas cooled reactor secondary circuit system when the remaining heat energy stored in the main energy storage tank does not meet the requirements, and the third auxiliary steam is generated by heating feedwater by the heat exchange system using the heat energy stored in the backup energy storage tank when the high temperature gas cooled reactor secondary circuit system is abnormal; the high temperature gas cooled reactor secondary circuit system and the heat exchange system are connected in parallel, and the high temperature gas cooled reactor secondary circuit system comprises an auxiliary electric boiler, which is used to heat feedwater to generate the second auxiliary steam during normal operation of the secondary circuit system. In this case, the reactor power does not need to be quickly adjusted when peak shaving and frequency modulation are required, and the frequency modulation and peak shaving function can be realized by using the molten salt heat storage system; during the start-up and commissioning stage, the auxiliary steam is provided for the high temperature gas cooled reactor unit by the combined operation of the molten salt heat storage system and the auxiliary electric boiler, and the auxiliary steam is independently provided by the molten salt heat storage system when the auxiliary electric boiler fails, so that the auxiliary steam is provided when the auxiliary electric boiler fails and the frequency modulation and peak shaving can be performed.

[0023] Additional aspects and advantages of the present disclosure will be made apparent from the following description, which, taken in conjunction with the accompanying drawings, that will be part hereof. BRIEF DESCRIPTION OF DRAWINGS

[0024] The above and / or additional aspects and advantages of the present disclosure will become apparent and be readily appreciated from the following description, taken in conjunction with the accompanying drawings, in which:

[0025] Figure 1 A high temperature gas cooled reactor and molten salt heat storage coupled operation system provided by an embodiment of the present disclosure is shown in a block diagram;

[0026] Figure 2 A structural schematic diagram of a high temperature gas cooled reactor and molten salt heat storage coupled operation system provided by an embodiment of the present disclosure is shown;

[0027] Figure 3 A flow schematic diagram of a high temperature gas cooled reactor and molten salt heat storage coupled operation method provided by an embodiment of the present disclosure is shown;

[0028] BRIEF DESCRIPTION OF DRAWINGS

[0029] 1 - generator; 2 - main transformer; 3 - high voltage auxiliary transformer; 4 - first section of auxiliary power thermal storage; 5 - second section of auxiliary power thermal storage; 6 - first thermal storage transformer switch; 7 - second thermal storage transformer switch; 8 - first thermal storage transformer; 9 - second thermal storage transformer; 10 - intelligent power conditioning unit; 11 - electric heater control switch set; 12 - electric heater set; 13 - low temperature molten salt tank; 14 - low temperature molten salt pump; 15 - low temperature molten salt flow controller; 16 - low temperature molten salt control valve set; 17 - high temperature molten salt tank set; 18 - high temperature molten salt control valve set; 19 - check valve set; 20 - high temperature molten salt pump; 21 - high temperature molten salt flow controller; 22 - heat exchanger; 23 - heat exchanger feed water flow control valve; 24 - heat exchanger steam flow control valve; 25 - auxiliary electric boiler; 26 - auxiliary electric boiler feed water flow control valve; 27 - auxiliary electric boiler steam flow control valve. DETAILED DESCRIPTION

[0030] The exemplary embodiments will be described in detail herein with reference to the attached drawings. In the following description, like reference numerals refer to like elements, unless the context clearly dictates otherwise. The following description is not meant to limit the application to the embodiments described herein. Rather, the following description is meant to provide an example of devices and methods consistent with the application as detailed in the appended claims.

[0031] In the description of the specification, the description using terms such as "one embodiment", "some embodiments", "an example", "a specific example", or "some examples" etc. means that a specific feature, structure, material or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. Descriptive expressions of the above terms in the specification do not necessarily refer to the same embodiment or example. Also, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in one or more embodiments or examples. In addition, different embodiments or examples described in the specification and features of different embodiments or examples can be combined and combined by those skilled in the art without contradiction.

[0032] In addition, the terms "first", "second", etc. are used only for descriptive purposes and should not be construed as indicating or implying relative importance or implying the number of the technical features indicated. Therefore, the features defined with "first", "second" can explicitly or implicitly include at least one of the features. In the description of the present disclosure, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited. It should also be understood that the term "and / or" used in the present disclosure means and includes any or all possible combinations of one or more associated listed items.

[0033] Embodiments of the present disclosure are described in detail below with reference to the attached drawing figures, wherein the same or like component have the same or similar designations. The embodiments described below are exemplary in nature, and are intended to be illustrative of the present disclosure rather than to be limiting of the present disclosure.

[0034] Currently, there are still some problems in the high-temperature gas cooled reactor demonstration project, including long startup time and large energy consumption of auxiliary electric boiler; in the unit startup stage, failure of the auxiliary boiler will cause the shaft seal system to lose auxiliary steam; due to nuclear safety, reactor power cannot be quickly changed, and other factors, the unit does not consider the frequency modulation and peak shaving operation mode, etc. In order to effectively solve the above problems and improve the economy and reliability of the operation of the high-temperature gas cooled reactor unit, the present disclosure provides a high-temperature gas cooled reactor and molten salt heat storage coupled operation system and method, the main purpose of the coupled operation system and method is to provide auxiliary steam when the auxiliary electric boiler fails, and to be able to carry out frequency modulation and peak shaving.

[0035] The primary loop of the high-temperature gas cooled reactor uses helium as the cooling medium and heat exchange medium, and the secondary loop uses water / water vapor as the heat exchange medium. Among them, in the unit startup stage or debugging stage, the auxiliary electric boiler heats the feed water to provide auxiliary steam for important systems of the unit, such as the shaft seal system, etc. The auxiliary electric boiler is powered by an external 110kV power supply through a high-voltage auxiliary transformer. The high-temperature gas cooled reactor and molten salt heat storage coupled operation system of the present disclosure adds a molten salt heat storage system, which is coupled with the high-temperature gas cooled reactor secondary loop system.

[0036] In a first embodiment, Figure 1 A block diagram of a high-temperature gas cooled reactor and molten salt heat storage coupled operation system provided by an embodiment of the present disclosure is shown. As Figure 1 shown, the high-temperature gas cooled reactor and molten salt heat storage coupled operation system includes a molten salt heat storage system and a high-temperature gas cooled reactor secondary loop system.

[0037] In the embodiment, the molten salt heat storage system comprises a heating system, a heat storage system and a heat exchange system, the heat storage system comprises a main energy storage tank and a backup energy storage tank, and the molten salt heat storage system is used to heat the molten salt in the heat storage system by the heating system to complete peak shaving and frequency modulation when a downward adjustment peak shaving and frequency modulation instruction is received during normal operation of the high-temperature gas cooled reactor; when the high-temperature gas cooled reactor is in a start-up debugging stage, the heat energy stored in the main energy storage tank is used to heat feed water through the heat exchange system to generate first auxiliary steam, and when the remaining heat energy stored in the main energy storage tank does not meet the requirement, second auxiliary steam is generated by the high-temperature gas cooled reactor secondary loop system, and if the high-temperature gas cooled reactor secondary loop system is abnormal, the backup energy storage tank is started, and the heat energy stored in the backup energy storage tank is used to heat feed water through the heat exchange system to generate third auxiliary steam. The remaining heat energy stored in the main energy storage tank does not meet the requirement refers to that the working time supported by the remaining heat energy stored in the main energy storage tank is not more than the start-up time of the auxiliary electric boiler with a preset multiple. The preset multiple is, for example, 1.5 times.

[0038] Specifically, in the embodiment, the heating system comprises a preset number of electric heaters, and the preset number is determined according to the peak shaving capacity of the high-temperature gas cooled reactor unit and the parameters of the molten salt heat storage system. The electric heaters are used to heat low-temperature molten salt into high-temperature molten salt.

[0039] In the embodiment, the heating system further comprises electric heater control switches, and the number of the electric heater control switches is equal to the number of the electric heaters. If the number of the electric heaters is n, the number of the electric heater control switches is n, each electric heater is connected to an electric heater control switch, and the electric heater connected to the electric heater control switch starts to work when the electric heater control switch is turned on.

[0040] In the embodiment, the heating system further comprises an intelligent power regulation device. All the electric heater control switches are connected to the intelligent power regulation device. The intelligent power regulation device is used to perform calculation and analysis based on the downward adjustment peak shaving and frequency modulation instruction to control the on-off of each electric heater control switch. Specifically, according to the power value required to be adjusted by the grid regulation instruction (for example, the peak shaving and frequency modulation instruction) or the unit operation state, the intelligent power regulation device quickly calculates and analyzes the number of electric heaters to be put into operation and the flow of molten salt required, and controls the corresponding electric heater switch to be turned on.

[0041] In the embodiment, the heating system further comprises a heat storage variable first switch, a heat storage variable second switch, a first heat storage variable and a second heat storage variable. The heat storage variable first switch is connected to the intelligent power regulation device through the first heat storage variable, and the heat storage variable second switch is connected to the intelligent power regulation device through the second heat storage variable. When the downward adjustment peak shaving and frequency modulation instruction is received, the heat storage variable first switch and the heat storage variable second switch are turned on, and the intelligent power regulation device starts to work.

[0042] In the embodiment, the heating system further comprises a generator, a high-voltage auxiliary transformer, an auxiliary power thermal storage first section, and an auxiliary power thermal storage second section. An outlet of the generator is further connected with the auxiliary power thermal storage first section and the auxiliary power thermal storage second section through the high-voltage auxiliary transformer. The electric heaters are evenly distributed in the auxiliary power thermal storage first section and the auxiliary power thermal storage second section. When the thermal storage transformer first switch and the thermal storage transformer second switch are closed, the electric power is heated to the electric heaters through the outlet of the generator, the high-voltage auxiliary transformer, the 6kV / 10kV auxiliary power thermal storage section (including the auxiliary power thermal storage first section and the auxiliary power thermal storage second section), the thermal storage transformer (including the first thermal storage transformer and the second thermal storage transformer).

[0043] In the embodiment, the intelligent power regulating device should also be evenly distributed in the auxiliary power thermal storage first section and the auxiliary power thermal storage second section when determining to put into the thermal storage branch.

[0044] In the embodiment, the outlet of the generator is further connected with the power grid through the main transformer.

[0045] Figure 2 A structure schematic diagram of a high-temperature gas cooled reactor and molten salt thermal storage coupled operation system provided by the embodiment of the present disclosure.

[0046] As shown in Figure 2 , the heating system comprises a generator 1, a high-voltage auxiliary transformer 3, an auxiliary power thermal storage section (including an auxiliary power thermal storage first section 4 and an auxiliary power thermal storage second section 5), a thermal storage transformer switch (including a thermal storage transformer first switch 6 and a thermal storage transformer second switch 7), a thermal storage transformer (including a first thermal storage transformer 8 and a second thermal storage transformer 9), an intelligent power regulating device 10, an electric heater control switch group 11, and an electric heater group 12. The electric heater control switch group 11 comprises n electric heater control switches, each of which is connected with the intelligent power regulating device 10. The electric heater group 12 comprises n electric heaters, and the value of n is determined according to the peak shaving capacity of the unit and the parameters of the molten salt thermal storage system. The n electric heaters are evenly distributed in the auxiliary power thermal storage first section 4 and the auxiliary power thermal storage second section 5. The intelligent power regulating device 10 can issue instructions to the electric heater control switch group 11, the low-temperature molten salt control valve group 16, and the flow controller 15 according to the grid regulating instruction or the unit power prediction curve, or can quickly calculate and analyze the current working state of the unit to realize real-time intelligent control of the working state of the molten salt thermal storage system.

[0047] In the embodiment, the thermal storage system comprises a low-temperature molten salt tank and a high-temperature molten salt tank. The low-temperature molten salt tank is used to store low-temperature molten salt. The high-temperature molten salt tank is used to store high-temperature molten salt.

[0048] In the embodiment, the number of high-temperature molten salt tanks is equal to the number of electric heaters, and each high-temperature molten salt tank is connected with an electric heater. The low-temperature molten salt from the low-temperature molten salt tank is sent into the high-temperature molten salt tank for storage after being heated by the electric heater. All the high-temperature molten salt tanks are divided into two parts, one part is the main energy storage tank, and the remaining part is the standby energy storage tank. The standby energy storage tank is used preferentially when the high-temperature gas-cooled reactor has a heat supply demand, and the standby energy storage tank is enabled when the high-temperature gas-cooled reactor secondary circuit system is abnormal.

[0049] In the embodiment, the thermal storage system further comprises a low-temperature molten salt pump, a low-temperature molten salt flow controller and a low-temperature molten salt control valve. The low-temperature molten salt pump is used to send the molten salt in the low-temperature molten salt tank into the electric heater. The low-temperature molten salt flow controller is used to control the flow of the low-temperature molten salt output by the low-temperature molten salt tank. The low-temperature molten salt control valve is turned on to enable the low-temperature molten salt to enter the electric heater. The low-temperature molten salt control valve is turned off to disable the low-temperature molten salt from entering the electric heater. According to the specific unit requirements, one set of low-temperature molten salt pump can be provided, or one large and one small set of low-temperature molten salt pumps can be provided, which are suitable for different operation modes and can be used as standby for each other.

[0050] In the embodiment, the number of low-temperature molten salt control valves is equal to the number of electric heaters, and each low-temperature molten salt control valve is connected with an electric heater and a high-temperature molten salt tank, and the low-temperature molten salt tank is connected with the low-temperature molten salt pump, the low-temperature molten salt flow controller and the low-temperature molten salt control valve. The corresponding thermal storage branch is selected by controlling the on-off of each low-temperature molten salt control valve.

[0051] In the embodiment, the low-temperature molten salt control valve and the high-temperature molten salt tank on the same branch form a thermal storage branch.

[0052] As shown in Figure 2 The thermal storage system comprises a low-temperature molten salt tank 13, a low-temperature molten salt pump 14, a low-temperature molten salt flow controller 15, a low-temperature molten salt control valve group 16 and a high-temperature molten salt tank group 17. If the number of electric heaters is n, the low-temperature molten salt control valve group 16 comprises n low-temperature molten salt control valves and n high-temperature molten salt tanks, thereby obtaining n thermal storage branches. The low-temperature molten salt in the low-temperature molten salt tank 13 enters the electric heater of the corresponding branch through the low-temperature molten salt pump 14 and the low-temperature molten salt control valve of the different thermal storage branches, and becomes high-temperature molten salt after being heated and is stored in the high-temperature molten salt tank of the corresponding thermal storage branch. The low-temperature molten salt intelligent flow controller 15 is installed after the low-temperature molten salt pump 14, which can control the low-temperature molten salt flow and the low-temperature molten salt control valve corresponding to each electric heater in the electric heater group 12 according to the instruction of the intelligent power adjustment device 10 in the heating system.

[0053] There are n heat storage branches in total, and m heat storage branches, i.e., m high-temperature molten salt tanks, are selected as standby energy storage tanks. The standby energy storage tanks serve as a standby heat source after the auxiliary electric boiler fails, are not put into use in normal operation, and are put into use after the auxiliary electric boiler 25 fails to ensure that the unit can be normally shut down. The value of the number m of the standby energy storage tanks can be determined according to the time for which the unit needs to continue to operate after losing the auxiliary steam of the auxiliary electric boiler 25. The m heat storage branches are evenly distributed in the first plant power heat storage section 4 and the second plant power heat storage section 5. The low-temperature molten salt tank 13 and the high-temperature molten salt tank group 17 are both provided with monitoring devices for detecting the amount of molten salt in the tanks, estimating the heat storage capacity of the high-temperature molten salt tank group 17, and reporting relevant data to the background in real time for use by the operating personnel, and are provided with an alarm function. The alarm threshold is set according to the working time supported by the residual energy of the main energy storage tank of the high-temperature molten salt tank group 17, which is not more than 1.5 times the starting time of the auxiliary electric boiler 25. In the heat storage system heat supply stage, when the residual energy of the main energy storage tank is insufficient (i.e., the alarm threshold is reached) and the auxiliary electric boiler needs to be put into use, the background alarm function prompts the operating personnel to start the auxiliary electric boiler in a timely manner. The number n needs to be determined according to the specific design calculation of the unit, for example, n is determined according to the peak shaving capacity of the unit.

[0054] In this embodiment, the heat exchange system includes a heat exchanger, which includes a molten salt inlet, a molten salt outlet, a feedwater inlet, and a steam outlet. The heat exchanger is used to heat the feedwater into auxiliary steam using the high-temperature molten salt from the high-temperature molten salt tank.

[0055] In this embodiment, the heat exchange system further includes a high-temperature molten salt control valve, a check valve, a high-temperature molten salt pump, and a high-temperature molten salt flow controller. The high-temperature molten salt tank is connected to the heat exchange system through the high-temperature molten salt control valve, the check valve, the high-temperature molten salt pump, and the high-temperature molten salt flow controller. When the high-temperature molten salt control valve is turned on, the high-temperature molten salt can enter the heat exchanger. When the high-temperature molten salt control valve is turned off, the high-temperature molten salt cannot enter the heat exchanger. The check valve is used to prevent the molten salt in the pipeline from flowing back to the high-temperature molten salt tank. The high-temperature molten salt pump is used to send the high-temperature molten salt to the heat exchanger. The high-temperature molten salt flow controller is used to control the flow of the high-temperature molten salt output by the high-temperature molten salt tank.

[0056] In this embodiment, the number of high-temperature molten salt control valves is the same as the number of high-temperature molten salt tanks. The number of check valves is the same as the number of high-temperature molten salt tanks. In this embodiment, the heat exchange system further includes a heat exchanger feedwater flow control valve and a heat exchanger steam flow control valve. The heat exchanger feedwater flow control valve is arranged on the pipeline at the feedwater inlet, and the heat exchanger steam flow control valve is arranged on the pipeline at the steam outlet. The heat exchanger feedwater flow control valve is used to control the flow of the feedwater entering the heat exchanger. The heat exchanger steam flow control valve is used to control the flow of the water vapor output by the heat exchanger.

[0057] As Figure 2As shown, the heat storage system includes a high-temperature molten salt control valve group 18, a check valve group 19, a high-temperature molten salt pump 20, a high-temperature molten salt flow controller 21, a heat exchanger 22, a heat exchanger feed water flow control valve 23, and a heat exchanger steam flow control valve 24. The heat exchanger 22 is also referred to as a molten salt-water heat exchanger. The high-temperature molten salt in the high-temperature molten salt tank group 17 passes through the high-temperature molten salt control valve 18, the check valve 19 of each heat storage branch, and reaches the high-temperature molten salt pump 20, enters the heat exchanger 22, heats the feed water to generate auxiliary steam. The low-temperature molten salt after heat exchange returns to the low-temperature molten salt tank 13. The function of the check valve 19 is to prevent the high-temperature molten salt from flowing into other high-temperature molten salt tanks. If the number of high-temperature molten salt tanks is n, then the high-temperature molten salt control valve group 18 includes n high-temperature molten salt control valves, and the check valve group 19 includes n check valves. The high-temperature molten salt pump 20 is provided with a high-temperature molten salt intelligent flow controller 21, which controls the high-temperature molten salt control valve group 18 according to the unit operation instruction to control the number of high-temperature molten salt tanks in the group 17 and the flow of high-temperature molten salt.

[0058] In this embodiment, each heat storage branch includes one low-temperature molten salt control valve, one high-temperature molten salt tank, and one high-temperature molten salt control valve. Each heat storage branch is provided with one electric heater, and the electric heater is controlled by an independent switch to be put into operation.

[0059] In this embodiment, the high-temperature gas cooled reactor two-loop system is connected in parallel with the heat exchange system, and the high-temperature gas cooled reactor two-loop system includes an auxiliary electric boiler for heating the feed water to generate the second auxiliary steam when the two-loop system is normally operated.

[0060] Specifically, as shown in Figure 2 The high-temperature gas cooled reactor two-loop system includes an auxiliary electric boiler 25, an auxiliary electric boiler feed water flow control valve 26, and an auxiliary electric boiler steam flow control valve 27. The auxiliary electric boiler 25 shares one feed water input port and one auxiliary steam output port with the heat exchanger 22. When the high-temperature gas cooled reactor two-loop system is fault-free, the auxiliary electric boiler 25 can heat the feed water to output the second auxiliary steam. The auxiliary electric boiler feed water flow control valve 26 is arranged at the inlet pipeline of the auxiliary electric boiler 25, and the auxiliary electric boiler steam flow control valve 27 is arranged at the outlet pipeline of the auxiliary electric boiler 25. The auxiliary electric boiler feed water flow control valve 26 is used to control the flow of the feed water entering the auxiliary electric boiler 25, and the auxiliary electric boiler steam flow control valve 27 is used to control the flow of the auxiliary steam output by the auxiliary electric boiler 25.

[0061] Specifically, in combination with the high-temperature gas cooled reactor and molten salt heat storage coupled operation system shown in Figure 2 The operation mode of the high-temperature gas cooled reactor and molten salt heat storage coupled operation system of the present disclosure includes three modes, and the specific operation process is as follows:

[0062] Running mode one: when the high temperature gas cooled reactor unit is in normal operation state, after receiving the peak shaving instruction to reduce power (i.e. receiving the peak shaving and frequency modulation instruction to downward adjust, for example, from 30% of the electric load deep peak shaving to 20% of the electric load), control the first and second heat storage variable switches 6 and 7 to be closed, and control the first and second heat storage variables 8 and 9 to be put into operation. The intelligent power regulating device 10 quickly analyzes and calculates the number of electric heaters in the electric heater group 12 and the low temperature molten salt flow required to be put into operation according to the power value required to be adjusted by the grid regulating instruction (for example, the peak shaving and frequency modulation instruction) or according to the intelligent analysis result of the unit operation state, and quickly gives the low temperature molten salt pump 14 a running instruction to control the corresponding number of electric heater control switches in the electric heater control switch group 11 to be closed, and control the corresponding number of low temperature molten salt control valves in the low temperature molten salt control valve group 16 to be put into operation, so that the corresponding heat storage branch is put into operation. At this time, the electric power to be adjusted will be converted into high temperature molten salt by the corresponding number of electric heaters through the low temperature molten salt in the low temperature molten salt tank 13, and stored in the corresponding heat storage branch of the high temperature molten salt tank group 17. In this running mode, the excess electric power can be converted into heat energy storage, achieving the effect of deep frequency modulation and peak shaving.

[0063] Running mode two: when the high temperature gas cooled reactor unit is in the starting stage or the debugging stage, first, the auxiliary steam is generated by the heat supply of the main energy storage tank of the heat storage system, and then the auxiliary steam is generated by the auxiliary electric boiler 25 when the main energy storage tank of the heat storage system is insufficient in heat storage. Specifically, according to the unit operation instruction, control the corresponding high temperature molten salt control valve of the main energy storage tank in the high temperature molten salt control valve group 18 to operate, and control the high temperature molten salt pump 20 to operate. The high temperature molten salt in the main energy storage tank flows through the heat exchanger 22 to heat the feed water to generate the first auxiliary steam, and the heat exchanged molten salt returns to the low temperature molten salt tank 13. During this process, the standby energy storage tank does not participate in the operation. When the remaining energy of the main energy storage tank in the high temperature molten salt tank group 17 reaches the alarm threshold, i.e. the working time supported by the remaining energy of the main energy storage tank is not more than 1.5 times the starting time of the auxiliary electric boiler 25, the background alarm device alarms and prompts the operator to start the auxiliary electric boiler 25 to provide the second auxiliary steam through the auxiliary electric boiler 25.

[0064] Running mode three: this mode is a standby running mode. When the high temperature gas cooled reactor unit is in the starting stage or the debugging stage, after the auxiliary electric boiler 25 fails to start or loses external power supply and stops, the standby energy storage tank in the high temperature molten salt tank group 17 is quickly started, the corresponding high temperature molten salt control valve in the high temperature molten salt control valve group 18 is opened, and the high temperature molten salt pump 20 is started to heat the feed water through the heat exchanger 22 to provide the third auxiliary steam. This standby running mode can prevent the important systems such as shaft seal from failing due to the loss of auxiliary steam, causing the unit to be non-stop.

[0065] In some embodiments, according to the future design requirements of nuclear power plants, the molten salt heat storage system can assist in providing main steam in the normal operation stage to improve energy utilization efficiency; can participate in the heating of the living area of the nuclear power plant; and if necessary, can provide important energy support in the future black start of the nuclear power unit.

[0066] The high-temperature gas cooled reactor coupled with the molten salt heat storage operation system of the embodiments of the present disclosure has multiple beneficial effects, specifically including: when the high-temperature gas cooled reactor unit needs to be peak-regulated and power-reduced, the excess electric power is converted into heat energy for storage, so that the high-temperature gas cooled reactor unit has a deep peak-regulation capability; in the unit start-up or debugging stage, auxiliary steam is provided in cooperation with an auxiliary electric boiler to overcome the problem of long start-up time of the auxiliary electric boiler and improve energy utilization rate; in the unit start-up or debugging stage, a backup heat source is provided, and after the auxiliary electric boiler fails, auxiliary steam can still be provided for the unit to prevent the unit from being shut down, thereby improving the reliability and safety of the operation of the high-temperature gas cooled reactor nuclear power plant; and the system has scalability, and as the future high-temperature gas cooled reactor unit continues to develop, it can provide support for more expansion functions.

[0067] In the high-temperature gas cooled reactor and molten salt heat storage coupled operation system, the coupled operation system comprises a molten salt heat storage system and a high-temperature gas cooled reactor secondary circuit system; the molten salt heat storage system comprises a heating system, a heat storage system and a heat exchange system, the heat storage system comprises a main energy storage tank and a backup energy storage tank, and the molten salt heat storage system is used to heat molten salt in the heat storage system by the heating system to complete peak shaving and frequency modulation when a downward adjustment peak shaving and frequency modulation instruction is received during normal operation of the high-temperature gas cooled reactor; during a start-up debugging stage of the high-temperature gas cooled reactor, the main energy storage tank is used to store heat energy, the heat energy is used to heat feed water by the heat exchange system to generate first auxiliary steam, and the high-temperature gas cooled reactor secondary circuit system is used to generate second auxiliary steam when the remaining heat energy stored in the main energy storage tank cannot meet the requirement, and the backup energy storage tank is started when the high-temperature gas cooled reactor secondary circuit system is abnormal, the backup energy storage tank is used to store heat energy, and the heat energy is used to heat feed water by the heat exchange system to generate third auxiliary steam; the high-temperature gas cooled reactor secondary circuit system and the heat exchange system are connected in parallel, and the high-temperature gas cooled reactor secondary circuit system comprises an auxiliary electric boiler, and the auxiliary electric boiler is used to heat feed water to generate second auxiliary steam during normal operation of the secondary circuit system. In this case, the reactor power does not need to be quickly adjusted when peak shaving and frequency modulation is required, and the molten salt heat storage system can be used to realize the function of frequency modulation and peak shaving; during the start-up debugging stage, the molten salt heat storage system and the auxiliary electric boiler are jointly used to provide auxiliary steam for the high-temperature gas cooled reactor unit, and the molten salt heat storage system is used to independently provide auxiliary steam when the auxiliary electric boiler fails, so that auxiliary steam can be provided when the auxiliary electric boiler fails, and frequency modulation and peak shaving can be realized. The system of the present disclosure aims to solve the problems of long start-up time, high power consumption and low working reliability of the auxiliary electric boiler of the high-temperature gas cooled reactor, and the cold molten salt energy is heated by the auxiliary power system, so that the function of frequency modulation and peak shaving can be realized without quickly adjusting the reactor power. At the same time, the system can be jointly used with the auxiliary electric boiler to provide auxiliary steam for the unit during the start-up stage of the unit, and can independently provide auxiliary steam when the electric boiler fails, thereby effectively reducing the energy consumption of the auxiliary electric boiler and improving the reliability and safety of the unit.

[0068] The following is an embodiment of the method of the present disclosure. For details not disclosed in the method embodiment of the present disclosure, please refer to the system embodiment of the present disclosure. The method embodiment of the present disclosure proposes a high-temperature gas cooled reactor and molten salt heat storage coupled operation method. The high-temperature gas cooled reactor and molten salt heat storage coupled operation method uses the high-temperature gas cooled reactor and molten salt heat storage coupled operation system of the above-mentioned system embodiment to realize frequency modulation and peak shaving and provide auxiliary steam.

[0069] Figure 3 A flowchart of a high-temperature gas cooled reactor and molten salt heat storage coupled operation method provided by an embodiment of the present disclosure is shown in FIG. 1. As shown in FIG. 1, the high-temperature gas cooled reactor and molten salt heat storage coupled operation method comprises the following steps. Figure 3

[0070] ​Step S11, if a peak shaving and frequency modulation instruction of downward adjustment is received when the high-temperature gas cooled reactor is in normal operation, the heating system of the molten salt heat storage system is controlled to heat the molten salt in the heat storage system, so as to complete peak shaving and frequency modulation;

[0071] Step S12, when the high-temperature gas cooled reactor is in a start-up debugging stage, the main energy storage tank of the heat storage system is started, and the heat energy stored in the main energy storage tank is used to heat feed water through the heat exchange system to generate first auxiliary steam;

[0072] Step S13, when the remaining heat energy stored in the main energy storage tank does not meet the requirements, the second auxiliary steam is generated by using the high-temperature gas cooled reactor two-loop system;

[0073] Step S14, if the high-temperature gas cooled reactor two-loop system is abnormal, the standby energy storage tank of the heat storage system is started, and the heat energy stored in the standby energy storage tank is used to heat feed water through the heat exchange system to generate third auxiliary steam.

[0074] Steps S11 to S14 can refer to the related description in the above system embodiment, which will not be repeated here.

[0075] It should be noted that the foregoing explanation and description of the high-temperature gas cooled reactor and molten salt heat storage coupled operation system embodiment also applies to the high-temperature gas cooled reactor and molten salt heat storage coupled operation method of this embodiment, which will not be repeated here.

[0076] The above sequence numbers of the embodiments of the present disclosure are only for description, and do not represent the advantages and disadvantages of the embodiments.

[0077] In the method for operating the high-temperature gas cooled reactor coupled with the molten salt heat storage system, when the high-temperature gas cooled reactor is in normal operation, if a peak shaving and frequency modulation instruction of downward adjustment is received, the heating system of the molten salt heat storage system is controlled to heat the molten salt in the heat storage system, so as to complete the peak shaving and frequency modulation; when the high-temperature gas cooled reactor is in a start-up and debugging stage, the main energy storage tank of the heat storage system is started, and the heat energy stored in the main energy storage tank is used to heat feed water through a heat exchange system to generate first auxiliary steam; when the remaining heat energy stored in the main energy storage tank does not meet the requirement, second auxiliary steam is generated by using the high-temperature gas cooled reactor two-loop system; if the high-temperature gas cooled reactor two-loop system is abnormal, the standby energy storage tank of the heat storage system is started, and the heat energy stored in the standby energy storage tank is used to heat feed water through the heat exchange system to generate third auxiliary steam. In this case, the reactor power does not need to be quickly adjusted when peak shaving and frequency modulation are required, and the frequency modulation and peak shaving function can be realized by using the molten salt heat storage system; during the start-up and debugging stage, the molten salt heat storage system is used in combination with an auxiliary electric boiler to provide auxiliary steam for the high-temperature gas cooled reactor unit, and when the auxiliary electric boiler fails, the molten salt heat storage system is used to independently provide auxiliary steam, so that auxiliary steam can be provided when the auxiliary electric boiler fails and frequency modulation and peak shaving can be performed. The purpose of the method is to solve the problems of long start-up time, large power consumption and low working reliability of the auxiliary electric boiler of the high-temperature gas cooled reactor, and the cold molten salt energy is heated by the station service power system, so that the frequency modulation and peak shaving function can be realized without quickly adjusting the reactor power. At the same time, the method can be used in combination with the auxiliary electric boiler during the start-up stage of the unit to provide auxiliary steam for the unit, and when the electric boiler fails, auxiliary steam can be independently provided, thereby effectively reducing the energy consumption of the auxiliary electric boiler and improving the reliability and safety of the unit operation.

[0078] The structural schematic diagram according to the disclosed embodiment of the present application is shown in the accompanying drawings. These drawings are not drawn to scale, in which some details are exaggerated for the purpose of clear expression, and some details can be omitted. The shapes of various regions, layers and the relative size and position relationship therebetween shown in the drawings are only exemplary, and in actuality, there can be deviations due to manufacturing tolerances or technical limitations, and a person skilled in the art can additionally design regions / layers with different shapes, sizes and relative positions according to actual needs.

[0079] It should be understood that the steps shown above can be reordered, added or deleted. For example, the steps described in the present disclosure can be executed in parallel, in sequence or in different orders, as long as the desired results of the technical solutions disclosed in the present disclosure can be achieved, and the present disclosure is not limited in this regard.

[0080] The above detailed description does not limit the scope of the disclosure. Various modifications, combinations, sub-combinations and alternatives can be made to the detailed description. Any modification, equivalent replacement and improvement etc. made within the spirit and principle of the disclosure shall be included in the scope of the disclosure.

Claims

1. A system for operating a high temperature gas cooled reactor coupled with a molten salt thermal storage, characterized in that, The molten salt heat storage system and the high-temperature gas cooled reactor secondary loop system are connected in parallel. The molten salt heat storage system comprises a heating system, a heat storage system and a heat exchange system, the heat storage system comprises a main energy storage tank and a backup energy storage tank, the molten salt heat storage system is used for heating molten salt in the heat storage system by the heating system to complete peak shaving and frequency modulation when receiving a downward adjustment peak shaving and frequency modulation instruction during normal operation of the high-temperature gas cooled reactor, the main energy storage tank is used for storing heat energy, and the heat exchange system is used for heating feed water to generate first auxiliary steam when the high-temperature gas cooled reactor is in a start-up debugging stage, the high-temperature gas cooled reactor secondary loop system is used for generating second auxiliary steam when residual heat energy stored in the main energy storage tank cannot meet the requirement, and the backup energy storage tank is started to generate third auxiliary steam when the high-temperature gas cooled reactor secondary loop system is abnormal. The high-temperature gas cooled reactor secondary loop system is connected in parallel with the heat exchange system, and the high-temperature gas cooled reactor secondary loop system comprises an auxiliary electric boiler, which is used for heating feed water to generate second auxiliary steam during normal operation of the secondary loop system. The residual heat energy stored in the main energy storage tank cannot meet the requirement refers to that working time supported by the residual heat energy stored in the main energy storage tank is not more than a preset multiple of start-up time of the auxiliary electric boiler, and the preset multiple is 1.5 times.

2. The high-temperature gas-cooled reactor and molten salt thermal storage coupled operation system as described in claim 1, characterized in that, The heating system comprises a preset number of electric heaters, and the preset number is determined according to a peak shaving capacity of the high-temperature gas cooled reactor unit and parameters of the molten salt heat storage system.

3. The high-temperature gas-cooled reactor and molten salt thermal storage coupled operation system as described in claim 2, characterized in that, The heating system further comprises an intelligent power regulation device and an electric heater control switch, the number of the electric heater control switches is equal to the number of the electric heaters, each electric heater is connected with an electric heater control switch, and the intelligent power regulation device is used for calculation and analysis based on the downward adjustment peak shaving and frequency modulation instruction to control on-off of each electric heater control switch.

4. The high-temperature gas-cooled reactor and molten salt thermal storage coupled operation system as described in claim 3, characterized in that, The heat storage system comprises a low-temperature molten salt tank and a high-temperature molten salt tank, and the number of the high-temperature molten salt tank is equal to the number of the electric heaters, and each high-temperature molten salt tank is connected with an electric heater.

5. The high-temperature gas-cooled reactor and molten salt thermal storage coupled operation system as described in claim 4, characterized in that, The heat storage system further comprises a low-temperature molten salt pump, a low-temperature molten salt flow controller and a low-temperature molten salt control valve, the number of the low-temperature molten salt control valve is equal to the number of the electric heaters, each low-temperature molten salt control valve is connected with an electric heater and a high-temperature molten salt tank, and the low-temperature molten salt tank is connected with the low-temperature molten salt pump, the low-temperature molten salt flow controller and the low-temperature molten salt control valve.

6. The high-temperature gas-cooled reactor and molten salt thermal storage coupled operation system as described in claim 5, characterized in that, The heat exchange system comprises a heat exchanger, and the heat exchanger comprises a molten salt inlet, a molten salt outlet, a feed water inlet and a steam outlet.

7. The high-temperature gas-cooled reactor and molten salt thermal storage coupled operation system as described in claim 6, characterized in that, The heat exchange system further comprises a high-temperature molten salt control valve, a check valve, a high-temperature molten salt pump and a high-temperature molten salt flow controller, and the high-temperature molten salt tank is connected with the high-temperature molten salt control valve, the check valve, the high-temperature molten salt pump and the high-temperature molten salt flow controller and the heat exchanger.

8. The high-temperature gas-cooled reactor and molten salt thermal storage coupled operation system as described in claim 7, characterized in that, The heat exchange system further comprises a heat exchanger feed water flow control valve arranged on a pipeline at the feed water inlet and a heat exchanger steam flow control valve arranged on a pipeline at the steam outlet.

9. A high temperature gas cooled reactor and molten salt heat storage coupled operation method based on the high temperature gas cooled reactor and molten salt heat storage coupled operation system according to any one of claims 1-8, characterized in that, Comprise: When the high-temperature gas cooled reactor is in normal operation, if a downward adjustment peak regulation and frequency modulation instruction is received, a heating system of a molten salt thermal storage system is controlled to heat the molten salt in the thermal storage system, thereby completing peak regulation and frequency modulation; When the high-temperature gas cooled reactor is in a start-up debugging stage, a main energy storage tank of the thermal storage system is started, and heat energy stored in the main energy storage tank is used to heat feed water through a heat exchange system to generate first auxiliary steam; When the remaining heat energy stored in the main energy storage tank does not meet the requirements, second auxiliary steam is generated by using a high-temperature gas cooled reactor secondary loop system; If the high-temperature gas cooled reactor secondary loop system is abnormal, a standby energy storage tank of the thermal storage system is started, and heat energy stored in the standby energy storage tank is used to heat feed water through the heat exchange system to generate third auxiliary steam.

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