A high temperature molten salt heat rejection system

Abstract

The application discloses a high-temperature molten salt heat release system, which comprises a cold salt tank, a hot salt tank, a gas supply system, a water supply system, a steam molten salt heat exchanger and a water supply molten salt heat exchanger, the input end of the hot salt tank is connected with the gas outlet end of a heat storage system, the output end is connected with the steam molten salt heat exchanger and an adjacent hot salt tank, the heat input end of the steam molten salt heat exchanger is connected with the hot salt tank, the heat output end is connected with a reheater outlet header and a thermal system respectively, and the gas inlet end is connected with the gas supply system, the heat input end of the water supply molten salt heat exchanger is connected with the steam molten salt heat exchanger, the heat output end is connected with the thermal system, the cold outlet end is connected with the cold salt tank, the water inlet end is connected with the water supply system, and a heat utilization pipeline is arranged between the water inlet end and a high-pressure water supply pipeline of the water supply system, the application can realize the reduction of unit coal consumption by improving the temperature of the water supply and the cold reheated steam, and can avoid the problem that the molten salt outlet temperature can only reach the water side pressure saturation temperature value, thereby reducing the molten salt utilization temperature interval.

Description

TECHNICAL FIELD

[0001] The application relates to a high-temperature molten salt heat release system and belongs to the field of clean heating. BACKGROUND

[0002] In China, the proportion of thermal power plants in all thermal power plants is very large, and the effective utilization of power plant waste heat has made important contributions to energy saving and emission reduction. However, with the development of the new situation, thermal power plants are facing challenges. Generally, users use less steam at night, and in order to meet the minimum load operation requirements, on the other hand, due to the difficulty of meeting the requirements of flue gas environmental protection under low load, thermal power plants need to open the back pressure machine to discharge steam to improve the unit load. In order to ensure the safe and efficient operation of the thermal power plant unit during the steam low period, and to solve the problem of improving the steam supply capacity of the thermal power plant during the steam peak period, it is necessary to reform the heat peak shaving of the thermal power plant. The existing molten salt heat storage peak shaving steam supply system uses the steam of the unit to heat the molten salt to store heat during the steam low period, and uses the high-temperature molten salt to heat the feed water to supply steam to the outside during the steam peak period. Due to the large heat release of steam in the condensation heat release process, according to the heat balance calculation, the outlet temperature of the molten salt will be greatly improved, but in fact the steam temperature in the steam condensation heat release process is always the saturation temperature corresponding to the system pressure, and the value does not change, so that the outlet temperature of the molten salt can only reach the saturation temperature value corresponding to the water side pressure, and the temperature range of the molten salt is small. SUMMARY

[0003] Therefore, the application provides a high-temperature molten salt heat release system to solve the problem that the temperature range of the molten salt is small due to the constant saturation temperature value corresponding to the water side pressure in the prior art. The specific scheme is as follows:

[0004] A high-temperature molten salt heat release system, comprising:

[0005] A cold salt tank is provided with a molten salt pump;

[0006] A hot salt tank is provided with a molten salt pump, the input end of the hot salt tank is connected with the gas outlet end of the heat storage system, and the output end is connected with a steam-molten salt heat exchanger and an adjacent hot salt tank;

[0007] A gas supply system;

[0008] A water supply system;

[0009] A steam-molten salt heat exchanger is connected with the hot salt tank at the heat input end, and is connected with a boiler low-temperature reheater outlet header and a thermal system at the heat output end, and the gas inlet end of the steam-molten salt heat exchanger is connected with the gas supply system;

[0010] The water feed molten salt heat exchanger is connected with the steam molten salt heat exchanger at the hot end, connected with the thermal system at the hot end, and connected with the cold salt tank at the cold end, the water inlet end of the water feed molten salt heat exchanger is connected with the water feed system, and a heat utilization pipeline is arranged between the water inlet end of the water feed molten salt heat exchanger and the high-pressure water pipeline of the water feed system.

[0011] The heat utilization pipeline is connected with the high-pressure pipeline before the boiler low-temperature coal economizer.

[0012] Preferably, the steam molten salt heat exchanger is provided with an electromagnetic valve on the pipeline from the steam molten salt heat exchanger to the boiler low-temperature reheater outlet header, and the water feed molten salt heat exchanger is provided with an electromagnetic valve on the water inlet end and the water outlet end of the heat utilization pipeline and the cold outlet pipeline of the water feed molten salt heat exchanger.

[0013] Preferably, the hot end of the hot salt tank and the input end of the water feed molten salt heat exchanger are respectively provided with pneumatic valves.

[0014] Preferably, the gas supply system comprises a low-temperature reheater and a cold reheating shunt pipeline.

[0015] The low-temperature reheater and the cold reheating shunt pipeline are connected in parallel to the gas inlet end of the steam molten salt heat exchanger.

[0016] Preferably, the material of the low-temperature reheater is 15CrMoG.

[0017] Preferably, an adjusting system is arranged between the cold reheating shunt pipeline and the low-temperature reheater.

[0018] The adjusting system comprises a monitoring unit, a controller and an adjusting unit.

[0019] The adjusting unit is located at the parallel connection position of the cold reheating shunt pipeline and the low-temperature reheater.

[0020] The monitoring unit is located between the hot end of the steam molten salt heat exchanger, the low-temperature reheater and the adjusting unit, and between the cold reheating shunt and the adjusting unit.

[0021] The monitoring unit and the adjusting unit are connected with the controller.

[0022] Preferably, the monitoring unit comprises a temperature sensor and a gas flow meter.

[0023] The temperature sensor, the gas flow meter and the adjusting unit are respectively installed on the pipeline between the low-temperature reheater and the adjusting unit and the cold reheating shunt pipeline and the adjusting unit, and the temperature sensor and the gas flow meter are connected with the controller.

[0024] Preferably, the temperature sensor, the gas flow meter and the adjusting unit are dynamically linked and controlled by a controller, respectively.

[0025] Preferably, the dynamic linkage and control is specifically as follows:

[0026] When the data detected by the temperature sensor and the gas flow meter exceeds the system set threshold value, the controller reduces the ventilation amount of the adjusting unit on the pipeline where the temperature sensor and the gas flow meter are located;

[0027] When the data detected by the temperature sensor and the gas flow meter is less than the system set threshold value, the controller increases the ventilation amount of the adjusting unit on the pipeline where the temperature sensor and the gas flow meter are located;

[0028] Finally, the temperature and flow of the heat outlet end of the steam molten salt heat exchanger meet the set value.

[0029] The application can produce beneficial effects, including:

[0030] In the non-depth peak shaving (i.e. heat release) period of the unit, in order to maintain the boiler at a certain load, the heat stored in the high-temperature storage tank (i.e. hot salt tank) of the molten salt is sent back to the unit thermal system in the form of heating cold reheat steam, and the heat-exchanged steam enters the boiler reheater; after the molten salt heats the cold section, the outlet of the high-pressure heater of the previous unit is connected to the high-pressure feedwater entering the heat exchange system, and the heat in the low-temperature section of the molten salt is sent back to the unit thermal system in the form of heating feedwater, and the heat-exchanged feedwater enters the boiler low-temperature economizer; finally, the low-temperature molten salt returns to the cold molten salt storage tank. By increasing the temperature of the feedwater and the cold reheat steam, the steam turbine output is increased under the condition that the boiler evaporation capacity is unchanged, the coal consumption of the unit is reduced, and the problem that the molten salt outlet temperature can only reach the water side pressure saturation temperature value is avoided, thereby causing the temperature interval of the molten salt to be small;

[0031] In the molten salt heat release process, due to the fact that the cold section splits off nearly half of the steam volume to the molten salt heat exchanger, the cold section flow entering the reheater is reduced, which causes the lowest level of the low-temperature reheater of the boiler to be seriously overheated, and therefore, in the application, the material of the low-temperature reheater of the last stage of the boiler is set to 15CrMoG;

[0032] By exchanging the heat stored in the hot salt tank to a part of the steam and feedwater extracted from the cold reheat steam pipeline and the high-pressure feedwater pipeline, the boiler load is kept unchanged when the unit is in the non-depth peak shaving stage (30% to 85% BMCR load);

[0033] By increasing the temperature of the cold reheat steam and the high-pressure feedwater entering the boiler, the purpose of saving fuel is achieved. Specifically, a steam (i.e. heat utilization pipeline) is led out from the cold reheat steam pipeline to the steam molten salt heat exchanger, absorbs the heat released by the molten salt on the shell side of the equipment, and the high-temperature steam obtained is returned to the low-temperature reheater header of the boiler. Attached Figure Description

[0034] Figure 1 This is a system schematic diagram of a high-temperature molten salt exothermic system according to one embodiment of this application.

[0035] List of components and reference numerals:

[0036] 1-Heat storage system; 2-Unit thermal system; 3-Steam molten salt heat exchanger; 4-Feedwater molten salt heat exchanger; 5-Cold reheat diversion pipeline; 6-Low-temperature reheater; 7-High-pressure feedwater pipeline outlet; 8-Check valve; 9-Next unit hot salt tank; 10-Boiler low-temperature reheater outlet header; 11-Cold salt tank; 12-Hot salt tank; 13-High-pressure feedwater pipeline; 14-Spring-loaded safety valve; 15-Three-way spring valve; 16-Pneumatic regulating valve; 17-Electric butterfly valve; 18-Pressure reducing valve; 19-Pneumatic valve; 20-Pneumatic butterfly valve; 21-Expansion valve; 22-Gate valve; 23-Solenoid valve. Detailed Implementation

[0037] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0038] According to the appendix Figure 1 The high-temperature molten salt exothermic system shown includes:

[0039] Cold salt tank 11 is equipped with a molten salt pump;

[0040] Hot salt tank 12 is equipped with a molten salt pump. The input end of the hot salt tank 12 is connected to the gas outlet end of the heat storage system 1, and the output end is connected to the steam molten salt heat exchanger 3 and the next unit hot salt tank 9 respectively.

[0041] Air supply system;

[0042] Water supply system;

[0043] The steam molten salt heat exchanger 3 has its inlet end connected to the hot salt tank 12, and its outlet end connected to the boiler low-temperature reheater outlet header 10 and the unit thermal system 2, respectively. The air inlet end of the steam molten salt heat exchanger 3 is connected to the air supply system.

[0044] The feedwater molten salt heat exchanger 4 has its inlet end connected to the steam molten salt heat exchanger, its outlet end connected to the unit's thermal system 2, and its outlet end connected to the cold salt tank 11. The inlet end of the feedwater molten salt heat exchanger 4 is connected to the feedwater system, and a heat utilization pipeline is provided between the inlet end of the feedwater molten salt heat exchanger and the high-pressure water transmission pipeline of the feedwater system.

[0045] The heat utilization pipeline is wound around the feed water molten salt heat exchanger 4, and the heat utilization pipeline is connected with the high pressure pipeline before the boiler low temperature economizer inlet. Specifically, one end of the heat utilization pipeline is connected with the high pressure feed water pipeline outlet 7, and the other end of the heat utilization pipeline is connected with the high pressure feed water pipeline inlet 13.

[0046] The input end of the heat utilization pipeline and the pipeline of the high pressure feed water pipeline outlet are respectively provided with a pneumatic regulating valve 16, a gate valve 22 and a solenoid valve 23; the output end of the heat utilization pipeline and the main pipeline between the high pressure feed water pipeline inlet are respectively provided with a solenoid valve 23 and a check valve 8, and the branch pipeline from the output end of the heat utilization pipeline to the high pressure feed water pipeline inlet 13 is provided with a pressure reducing valve 18.

[0047] Further, the heat input pipeline and the air inlet pipeline of the steam molten salt heat exchanger 3, the pipeline from the steam molten salt heat exchanger to the boiler low temperature reheater outlet header, and the water inlet end and the water outlet end of the heat utilization pipeline connected with the feed water molten salt heat exchanger and the cold outlet pipeline of the feed water molten salt heat exchanger are respectively provided with solenoid valves.

[0048] Further, the heat outlet end of the hot salt tank 12 and the input end of the heat utilization pipeline connected with the feed water molten salt heat exchanger 4 are respectively provided with pneumatic valves 16.

[0049] Further, two output pipelines are connected in parallel between the hot salt tank 12 and the steam molten heat exchanger 3, and expansion valves 21 are respectively installed in parallel on the two output pipelines; one output branch pipeline is arranged on the pipeline between the hot salt tank 12 and the steam molten heat exchanger 3, one end of the output branch pipeline is connected with the pipeline between the hot salt tank 12 and the steam molten heat exchanger 3, and the other end of the output branch pipeline is respectively connected with the next unit hot salt tank 9 and the hot salt tank 12, that is, the heat outlet end of the hot salt tank 12, one end of which enters the steam molten salt heat exchanger 3, and the other end is divided into two branch pipelines, one of which flows into the next unit hot salt tank 9, and the other of which returns to the hot salt tank 12.

[0050] Among them, pneumatic valves 19 are respectively arranged on the output branch pipeline and the pipeline returning to the hot salt tank 12; pneumatic butterfly valves 20 and expansion valves 21 are respectively arranged on the two heat outlet pipelines connected in parallel with the hot salt tank 12;

[0051] Further, the gas supply system comprises a low temperature reheater 6 and a cold reheating shunt pipeline 5.

[0052] The low temperature reheater 6 and the cold reheating shunt pipeline 5 are connected in parallel to the air inlet end of the steam molten salt heat exchanger 3, and are used to provide heat exchange steam for the steam molten salt heat exchanger 3; an electric butterfly valve 17 is arranged between the cold reheating shunt pipeline 5 and the low temperature reheater 6 connected in parallel.

[0053] Further, an adjusting system is arranged between the cold reheating shunt pipeline 5 and the low temperature reheater 6.

[0054] The adjusting system comprises a monitoring unit, a controller and an adjusting unit;

[0055] The adjusting unit is located at a parallel connection position of the cold reheat bypass pipeline and the low-temperature reheat device 6;

[0056] The detecting unit is respectively located between the heat outlet end of the steam molten salt heat exchanger 3, the low-temperature reheat device 6 and the adjusting unit, and between the cold reheat bypass pipeline 5 and the adjusting unit;

[0057] The monitoring unit and the adjusting unit are respectively connected with the controller.

[0058] Further, the material of the low-temperature reheat device is 15CrMoG.

[0059] Further, the monitoring unit comprises a temperature sensor and a gas flow meter;

[0060] The temperature sensor, the gas flow meter and the adjusting unit are respectively installed in the pipeline between the low-temperature reheat device and the adjusting unit, and between the cold reheat bypass pipeline and the adjusting unit, and the temperature sensor and the gas flow meter are respectively connected with the controller.

[0061] Further, the temperature sensor, the gas flow meter and the adjusting unit are respectively dynamically linked and controlled through the controller.

[0062] Further, the linkage control specifically comprises:

[0063] When the data detected by the temperature sensor and the gas flow meter exceeds the system set threshold value, the controller reduces the air amount of the adjusting unit on the pipeline where the temperature sensor and the gas flow meter are located;

[0064] When the data detected by the temperature sensor and the gas flow meter is less than the system set threshold value, the controller increases the air amount of the adjusting unit on the pipeline where the temperature sensor and the gas flow meter are located;

[0065] Finally, the temperature and flow of the heat outlet end of the steam molten salt heat exchanger 3 meet the set value.

[0066] It should be noted that:

[0067] The system is a unit system, and the heat release system comprises the steam molten salt heat exchanger 3 and the feedwater molten salt heat exchanger 4, so as to realize the transfer of heat in the molten salt to the unit thermal system 2, and the specific process is as follows:

[0068] The steam molten salt heat exchanger 3 is connected with the hot salt tank at the input end of the hot body and connected with the boiler low-temperature reheating header outlet 10 at the output end of the hot body, the high-temperature molten salt is first introduced into the steam molten salt heat exchanger 3 through the molten salt heat pump, and the first heat exchange is performed between the high-temperature molten salt and the steam in the steam molten salt heat exchanger 3, so that the steam in the steam molten salt heat exchanger 3 is heated, thereby generating about 500 DEG C superheated steam into the boiler low-temperature reheating header outlet 10,

[0069] The feedwater molten salt heat exchanger 4 is connected with the steam molten salt heat exchanger 3 at the input end, the molten salt after the heat exchange with the steam molten salt heat exchanger 3 is introduced into the feedwater molten salt heat exchanger 4, and the second heat exchange is performed between the molten salt and the feedwater in the feedwater molten salt heat exchanger 4, so that the temperature of the feedwater is increased to about 320 DEG C, and the hot flow output end of the feedwater molten salt heat exchanger is also connected with the No. 3 external steam cooling outlet, so that the heated feedwater is mixed with the feedwater of the No. 3 external steam cooling outlet, and then introduced into the boiler low-temperature economizer, thereby replacing the function of part of the high-pressure heater.

[0070] The bottom of the cold salt tank 11 and the hot salt tank 12 is provided with a heater, and the heater is an immersed electric heater for molten salt anti-condensation heating;

[0071] The cold salt tank 11 and the hot salt tank 12 are respectively provided with a cold salt pump and a hot salt pump, the cold salt pump and the hot salt pump are frequency conversion pumps, and are vertical suspension type centrifugal pumps, the cold salt pump is supported on the top of the cold salt tank near the tank wall, the pump head is immersed in the low-temperature molten salt, and the molten salt is pumped into the steam molten salt heat exchanger to exchange heat with the steam. The design temperature of the cold salt pump is 320 DEG C, which is used for the material and thermal expansion mechanical design of the pump body, and the design flow of the pump group is the maximum heat exchange flow of the heat exchanger, that is, 610 t / h.

[0072] The design temperature of the hot salt pump is 580 DEG C, which is used for the material and thermal expansion mechanical design of the pump body, and the design flow is consistent with the flow of the cold salt pump, that is, 610 t / h.

[0073] The hot salt pump pumps the high-temperature molten salt from the hot salt tank to the steam molten salt heat exchanger to exchange heat with the cold reheated steam, and the temperature of the molten salt is reduced to about 435 DEG C after heat exchange, and the molten salt after heat exchange is introduced into the feedwater molten salt heat exchanger to exchange heat with the feedwater, and then returned to the cold salt tank at about 290 DEG C, in the process, the steam in the steam molten salt heat exchanger is heated from about 365 DEG C to about 500 DEG C and enters the boiler; at the same time, the feedwater in the feedwater molten salt heat exchanger is heated from about 257 DEG C to 320 DEG C, and then the heated feedwater is mixed with the feedwater of the No. 3 external steam cooling outlet.

[0074] In the present application, spring safety valves 14 are respectively arranged on the pipelines between the hot ends of the steam molten salt heat exchanger 3 and the feedwater molten salt heat exchanger 4 and the unit thermal system 2;

[0075] The feed water molten salt heat exchanger 4 is also provided with a three-way spring valve 15.

[0076] In the application, the process of heating cold reheat steam by molten salt is a scheme of splitting a part of steam from the cold reheat split pipe and connecting in parallel with the low-temperature reheater 6. The control of the steam splitting is realized by using an adjusting system. Specifically, temperature sensors, gas flow meters and adjusting units are arranged on the pipes between the low-temperature reheater and the adjusting unit and the pipes between the cold reheat split pipe and the adjusting unit. The adjusting unit is an electric butterfly valve 17 with adjusting function. The temperature sensor is an infrared non-contact sensor. The temperature sensor, the gas flow meter and the electric butterfly valve 17 are connected with a controller. When the data detected by the temperature sensor and the gas flow meter exceed the system set threshold value, the controller controls the adjusting unit on the pipe where the temperature sensor and the gas flow meter are located to reduce the air flow. When the data detected by the temperature sensor and the gas flow meter are less than the system set threshold value, the controller controls the adjusting unit on the pipe where the temperature sensor and the gas flow meter are located to increase the air flow. Finally, the temperature and flow of the hot end of the steam molten salt heat exchanger meet the set value.

[0077] In the application, in order to prevent the condensation of molten salt, the parts in contact with the molten salt in the whole system are provided with electric heating tapes to ensure that the temperature of the molten salt in the system is not lower than 260℃.

[0078] In the application, since the high-temperature molten salt in the application can reach a maximum temperature of about 560℃ during normal operation, a mineral insulated electric heating cable (abbreviated as MI) is selected in the application. The cable heating system uses hard alloy as the outer sleeve and magnesium oxide as the insulation to adapt to the high-temperature environment.

[0079] In the application, in addition to following the required temperature change rate of the steam turbine and controlling the reheated steam temperature not to exceed the lower limit during the operation of the steam turbine, the core components of the unit also need to be monitored. Therefore, in order to avoid damage to the steam turbine unit, in the application, the low-pressure cylinder of the steam turbine is sprayed with stainless steel, the low-pressure cylinder positive and negative direction penultimate stage blades are sprayed, and two temperature measuring points are added to the last stage of the low-pressure cylinder and four temperature measuring points are added to the penultimate stage.

[0080] At the same time, a steam supplementing path is added to the low-pressure cylinder, and an intelligent diagnosis system for low-load operation and an online blade vibration monitoring system are added. That is, frequent and severe load changes will cause the steam turbine blades to bear large thermal stress and alternating stress. The online blade vibration monitoring system is added to detect the vibration condition of the blades. Not only does it reduce the water erosion effect of the blades caused by low-load water spray cooling, but also it improves the regulation and efficiency of the unit under low load, and finally realizes the safe and stable operation of the main machine under 20% THA for a long time.

[0081] In the present application, due to the heat release process of the molten salt, the cold section diversion needs to divert nearly half of the steam volume to the steam-molten salt heat exchanger 3, which leads to the decrease of the cold section flow rate entering the low-temperature reheater 6, resulting in the over-temperature of the lowest stage of the low-temperature reheater 6 (i.e., due to the excessive cold section flow rate, the flue gas temperature of the low-temperature reheater cannot be reduced, and the over-temperature of the last stage of the low-temperature reheater is serious), therefore, the material of the last stage of the low-temperature reheater 6 of the boiler is changed from SA-210C to 15CrMoG. The outlet header 10 of the low-temperature reheater of the boiler is field drilled and welded, so that a part of the cold-reheated steam bypassing the low-temperature reheater 6 during the heat release process is heated by the molten salt heat exchanger 3 and then returned to the outlet header 10 of the low-temperature reheater.

[0082] In the present application, the return cold-reheated steam pipeline and the feedwater lead pipeline are added to the steam-water side system, as well as the steam-molten salt heat exchanger 3 and the molten salt-feedwater heat exchanger 4 and other equipment.

[0083] When the unit is in the non-deep tuning period (above 30% BMCR load), the heat release system is started at this time, and the high-temperature molten salt is pumped into the heat release system by the hot salt pump, and is exchanged with part of the cold-reheated steam and the feedwater respectively, about 500℃ steam and 320℃ feedwater are generated after the heat exchange respectively, the heat stored by the molten salt is sent back to the thermal system of the unit, and the output of the steam turbine is increased under the condition that the load of the boiler is unchanged. The molten salt of about 290℃ after heat exchange returns to the cold salt tank 11. According to the matching of the steam parameters, the molten salt heat release system can be started at any operating condition in the range of 30% to 85% BMCR of the unit. Due to the limitation of the cold-reheated steam flow rate entering the heating surface of the boiler and the high-pressure feedwater temperature, the heat release time of the unit at different loads is different. After the molten salt heat release system is put into operation, it can play a role in load regulation and frequency regulation within a certain range without increasing the coal consumption of the boiler;

[0084] In the present application, the heat utilization pipeline is wound on the outer shell of the feedwater molten salt evaporator 4, the input end of the heat utilization pipeline is connected to the outlet 7 of the high-pressure feedwater pipeline, and the output end of the heat utilization pipeline is connected to the inlet 13 of the high-pressure feedwater pipeline;

[0085] The outer side of the heat utilization pipeline wound on the outer shell of the feedwater molten salt evaporator is wrapped with MXene-rGO sponge (or rGMXn sponge). Since the MXene nanosheets in the rGMXn sponge are synthesized in situ on the surface of the rGO framework, the rGMXn sponge has excellent solar utilization efficiency, especially under weak natural light. Under 0.5 solar weak irradiance, the evaporation rate of the rGMX5 sponge reaches 1.6 kgm-2h-1, and the energy efficiency reaches 85%, so that the outer shell of the feedwater molten salt evaporator and the MXene-rGO sponge simultaneously heat the heat utilization pipeline wound on the outer shell of the feedwater molten salt evaporator from the inside and outside, thereby greatly improving the heat exchange efficiency of the heat utilization pipeline;

[0086] At the same time, the radial thermal conductivity coefficient (0.268 Wm-1K-1) of the rGMXn sponge is much larger than the axial thermal conductivity coefficient (0.025 Wm-1K-1), thereby reducing the heat loss on the heat utilization pipeline and further improving the energy loss of the heat utilization pipeline.

[0087] The above is only a few embodiments of the present application, and does not limit the present application in any form. Although the preferred embodiments are disclosed above, they are not intended to limit the present application. Any skilled person in the art can make some changes or modifications to the above disclosed technical content without departing from the scope of the technical solution of the present application, which are equivalent to equivalent embodiments and belong to the scope of the technical solution.

Claims

1. A high-temperature molten salt exothermic system, characterized in that, include: Cold salt tank, equipped with a molten salt pump; A hot salt tank is equipped with a molten salt pump. The input end of the hot salt tank is connected to the gas outlet of the thermal storage system, and the output end is connected to a steam-molten salt heat exchanger and an adjacent hot salt tank, respectively. Air supply system; Water supply system; The steam molten salt heat exchanger has its heat inlet end connected to a hot salt tank, and its heat outlet end connected to the boiler low-temperature reheater outlet header and the thermal system, respectively. The air inlet end of the steam molten salt heat exchanger is connected to the air supply system. The feedwater molten salt heat exchanger has a heat inlet connected to a steam molten salt heat exchanger, a heat outlet connected to a thermal system, and a cold outlet connected to a cold salt tank. The feedwater molten salt heat exchanger's inlet is connected to the feedwater system, and a heat utilization pipeline is provided between the feedwater molten salt heat exchanger's inlet and the high-pressure water supply pipeline of the feedwater system. The heat utilization pipelines are respectively connected to the high-pressure pipelines before the inlet of the feedwater molten salt heat exchanger and the boiler low-temperature economizer. The gas supply system includes a low-temperature reheater and a cold reheat branch line; The low-temperature reheater and the cold reheat diversion pipeline are connected in parallel to the inlet end of the steam molten salt heat exchanger.

2. The high-temperature molten salt exothermic system according to claim 1, characterized in that, Solenoid valves are respectively installed on the heat inlet pipe and air inlet pipe of the steam molten salt heat exchanger, on the pipe flowing from the steam molten salt heat exchanger to the outlet header of the boiler low-temperature reheater, and on the water inlet and outlet of the feedwater molten salt heat exchanger and the cold outlet pipe of the feedwater molten salt heat exchanger.

3. The high-temperature molten salt exothermic system according to claim 1, characterized in that, Pneumatic valves are respectively installed between the heat outlet end of the hot salt tank and the input end of the heat utilization pipeline and the feedwater molten salt heat exchanger.

4. The high-temperature molten salt exothermic system according to claim 1, characterized in that, The material of the low-temperature reheater is 15CrMoG.

5. The high-temperature molten salt exothermic system according to claim 1, characterized in that, Place A regulating system is installed between the cold reheat branch line and the low-temperature reheater; The regulation system includes a monitoring unit, a controller, and a regulation unit; The regulating unit is located at the parallel connection point between the cold reheat diversion pipeline and the low-temperature reheater; The monitoring units are located at the heat outlet of the steam molten salt heat exchanger, between the low-temperature reheater and the regulating unit, and between the cold reheat diverter and the regulating unit, respectively. The monitoring unit and the adjustment unit are respectively connected to the controller.

6. The high-temperature molten salt exothermic system according to claim 5, characterized in that, The monitoring unit includes a temperature sensor and a gas flow meter; The temperature sensor, the gas flow meter, and the regulating unit are respectively installed in the pipeline between the low-temperature reheater and the regulating unit, and between the cold reheat split pipeline and the regulating unit. The temperature sensor and the gas flow meter are respectively connected to the controller.

7. A high-temperature molten salt exothermic system according to claim 6, characterized in that, The temperature sensor, the gas flow meter, and the regulating unit are dynamically linked and controlled by a controller.

8. A high-temperature molten salt exothermic system according to claim 7, characterized in that, The linkage control specifically refers to: When the data detected by the temperature sensor and gas flow meter exceed the system's set threshold, the regulating unit on the pipeline where the controller's control degree sensor and gas flow meter are located reduces the airflow. When the data detected by the temperature sensor and the gas flow meter are less than the system set threshold, the regulating unit on the pipeline where the controller's control degree sensor and the gas flow meter are located increases the air flow. Ultimately, the temperature and flow rate at the outlet of the steam molten salt heat exchanger met the set values.

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