Molten Salt Energy Storage Cogeneration System and Its Molten Salt Energy Storage Heat Exchange Device

Abstract

The present invention discloses a molten salt energy storage thermoelectric cogeneration system and its molten salt energy storage heat exchanger, which relates to the technical field of high-temperature molten salt heat storage. The molten salt energy storage thermoelectric cogeneration system includes a low-temperature molten salt tank, a molten salt electric heater, an energy storage heat exchanger, a steam turbine feed water module, a reheater, a high-pressure cylinder, an intermediate-pressure cylinder, a low-pressure cylinder, and a condenser. A low-temperature molten salt pump is provided between the molten salt electric heater and the low-temperature molten salt tank. Heat storage process: The molten salt electric heater is used to heat the low-temperature molten salt in the low-temperature molten salt tank, and the heated high-temperature molten salt enters the energy storage heat exchanger. Heat release process: The steam turbine feed water module is used to supply water to the energy storage heat exchanger to enable heat exchange between the water and the high-temperature molten salt. This molten salt energy storage thermoelectric cogeneration system mainly takes the molten salt energy storage technology as the core, stores heat, comprehensively utilizes valley electricity and abandoned electricity, and adopts a structure that separates the heat exchange energy storage device from the molten salt electric heater to ensure the heating effect.

Description

Technical Field

[0001] The present invention relates to the technical field of high-temperature molten salt thermal energy storage, and specifically to a molten salt energy storage combined heat and power generation system and its molten salt energy storage heat exchange device. Background Art

[0002] Under carbon peaking and carbon neutrality, the installed capacity ratio of renewable energy sources such as wind power and photovoltaic power in China has been continuously increasing. According to data, as of the end of October 2021, the cumulative installed capacity of renewable energy power generation in China reached 1.002 billion kilowatts, doubling that at the end of 2015; the proportion in the total installed capacity of the national power generation reached 43.5%, 10.2 percentage points higher than that at the end of 2015.

[0003] Accelerating the construction of a new power system adapted to the development of a high proportion of renewable energy means that the power system will become increasingly low-carbon (renewable energy power generation) and decentralized (distributed power generation). Renewable energy power generation has randomness and volatility. According to "Analysis of Key Factors for New Energy Consumption and Research on Solutions", the maximum daily fluctuation of wind power can reach 80% of the installed capacity, and it shows a certain anti-peak shaving characteristic; photovoltaic power generation is affected by day and night changes, weather changes, and moving clouds, and also has intermittency and volatility. This means that the balancing process of a system with a high proportion of renewable energy access becomes increasingly complex. To ensure the stable, efficient, and safe operation of the system, the importance of power auxiliary services is becoming increasingly prominent.

[0004] Looking at the structure of the compensation fees for power auxiliary services, currently, peak shaving, frequency modulation, and reserve are the most main types in the power auxiliary service market in China, accounting for more than 90%. Taking the first half of 2019 as an example, the total peak shaving compensation fee was 5.009 billion yuan, accounting for 38.44% of the total compensation fee; the total frequency modulation compensation fee was 2.701 billion yuan, accounting for 20.73% of the total compensation fee; the total reserve compensation fee was 4.741 billion yuan, accounting for 36.38%; the voltage regulation compensation fee was 551 million yuan, accounting for 4.23%; and the other compensation fee was 29 million yuan, accounting for 0.22%.

[0005] Peak shaving services will gradually be replaced by the spot market. Comparing with the auxiliary service varieties in foreign mature markets, one big difference is that there is no peak shaving variety in the foreign power auxiliary service market, but it is achieved through the real-time market or balancing mechanism of the spot market. In the "Notice on Further Doing a Good Job in the Pilot Work of the Construction of the Power Spot Market" (Fa Gai Ban Ti Gai 〔2021〕No. 339) issued this year, it has also been clearly required that "during the operation of the spot market, the spot electricity energy market will replace the peak shaving market". With the continuous deepening of the power system reform, after the spot market is built and put into operation, the electricity price in the spot market will guide the output change of the generating units, thus replacing peak shaving.

[0006] In existing systems for energy storage and power generation using molten salt, generally, the molten salt in a heated high-temperature molten salt tank is pumped to a heat exchanger to exchange heat with water, and the generated steam is used for power generation.

[0007] To avoid heat loss caused by pumping the molten salt in the high-temperature molten salt tank to the heat exchanger, the water pipe system can be directly assembled inside the high-temperature molten salt tank.

[0008] In a patent with a similar application number CN201410114259.9, a single-tank electric energy storage device is proposed. During the energy storage stage: the heat storage medium is added to the energy storage tank body from the heat transfer medium inlet, and electric energy heats the heat storage medium in the energy storage tank through an electric heater, increasing its temperature, converting the electric energy into heat energy and transferring it to the heat storage medium, which is stored in the energy storage tank until the entire energy storage tank is filled with high-temperature heat storage medium, and the energy storage ends; the heat transfer medium can be molten salt, water, or other heat-conducting oils, etc. During the energy release stage: the low-temperature energy release medium enters the energy storage tank from the energy release medium inlet, exchanges heat with the high-temperature heat storage medium, and its temperature rises. The heated high-temperature energy release medium is discharged from the energy release medium outlet. The discharged high-temperature energy release medium is either directly used in the energy utilization device or passes through the energy utilization heat exchanger, and the energy is utilized through the energy utilization heat exchanger and the energy utilization device. Among them, the energy storage stage and the energy release stage can be carried out simultaneously.

[0009] However, generally, it is best to carry out energy storage during off-peak electricity periods and energy release during peak electricity periods. If the above energy storage heat exchange device adopts the method of simultaneous energy storage and energy release, it will result in using peak electricity for energy storage. If it adopts the state of separate energy release, with the progress of heat exchange, its overall temperature will become lower and lower over time. By 6 - 8 pm during the electricity peak period, its heat exchange capacity is severely insufficient, affecting the work done by the high-pressure cylinder, intermediate-pressure cylinder, and low-pressure cylinder, resulting in a serious decline in power generation and insufficient power supply.

[0010] For places with large electricity demands, the storage tanks for molten salt required are very large, with a storage capacity even reaching up to 5000 tons. The above structure with a heating device installed inside the tank has poor heating effects and is not applicable. Summary of the Invention

[0011] Aiming at the deficiencies of the existing technology, the present invention provides a molten salt energy storage cogeneration system and its molten salt energy storage heat exchange device, which solve the problems of poor heating effects caused by installing a heating device inside the storage tank and the decline in power generation capacity over time during the day in the existing technology.

[0012] To achieve the above objectives, on the one hand, the present invention provides a molten salt energy storage cogeneration system, including a low-temperature molten salt tank, a molten salt electric heater, an energy storage heat exchanger, a steam turbine feed water module, a reheater, a high-pressure cylinder, an intermediate-pressure cylinder, a low-pressure cylinder, and a condenser. A low-temperature molten salt pump is provided between the molten salt electric heater and the low-temperature molten salt tank:

[0013] Heat storage process: The molten salt electric heater can heat the low-temperature molten salt in the low-temperature molten salt tank, and the heated high-temperature molten salt enters the energy storage heat exchanger;

[0014] Heat release process: The steam turbine feed water module can supply water to the energy storage heat exchanger, enabling the water to exchange heat with the high-temperature molten salt and generating steam that can enter the high-pressure cylinder and the intermediate-pressure cylinder to do work. Part of the high-temperature molten salt in the energy storage heat exchanger can enter the reheater; the exhaust steam formed by the high-pressure cylinder and the intermediate-pressure cylinder can exchange heat with the high-temperature molten salt in the reheater, and the exhaust steam is heated and pressurized and enters the low-pressure cylinder to do work. The condenser can condense the high-temperature gas in the low-pressure cylinder, and the generated condensed water enters the steam turbine feed water module.

[0015] Further, reflux pipes are provided on both the energy storage heat exchanger and the reheater, and a waste liquid reflux pump is provided on the reflux pipe. The reflux pipe can send the low-temperature molten salt after heat exchange in the energy storage heat exchanger back to the low-temperature molten salt tank.

[0016] On the other hand, the present invention also provides a molten salt energy storage heat exchange device, including: a high-temperature molten salt tank for storing high-temperature molten salt; an internal floating disc disposed in the high-temperature molten salt tank along the radial section direction of the high-temperature molten salt tank, and the height of the internal floating disc changes with the liquid level height of the high-temperature molten salt; a heat exchange tube group assembled on the side of the internal floating disc close to the high-temperature molten salt and changing height synchronously with the internal floating disc, and the heat exchange tube group can exchange heat with the high-temperature molten salt in the area close to the internal floating disc; a reflux hose, one end of which passes through the internal floating disc and contacts the liquid surface of the high-temperature molten salt, and the other end of the reflux hose enters and connects the waste liquid reflux pump through a reflux pipe.

[0017] Further, a heat insulation board is fixedly provided on the side of the internal floating disc close to the high-temperature molten salt, and the heat exchange tube group is located in the area between the internal floating disc and the heat insulation board; the heat insulation board divides the molten salt in the high-temperature molten salt tank into two areas of molten salt, one area of molten salt is the molten salt in the area where the heat exchange tube group is located, and the other area of molten salt is the molten salt in the remaining area of the high-temperature molten salt tank, so as to reduce the heat exchange between the two areas of molten salt; multiple groups of through holes are provided on the heat insulation board, and valve plates are provided in the through holes. The valve plates can rotate in the through holes to control the through holes to be in an open or closed state, and when the heat insulation board is opened, the molten salt in the remaining area can enter the area where the heat exchange tube group is located.

[0018] Further, one end of the heat exchange tube group is fixedly provided with a first storage cylinder. A first connecting pipe fixedly communicating with the first storage cylinder is axially and fixedly penetrated through the inner floating disc. One end of the first connecting pipe away from the first storage cylinder is fixedly provided with a first compensating hose. The top of the high-temperature molten salt tank is fixedly provided with a third connecting pipe penetrating through the top layer of the tank. The third connecting pipe is fixedly connected to one end of the first compensating hose. The other end of the heat exchange tube group is fixedly provided with a second storage cylinder. A second connecting pipe fixedly communicating with the second storage cylinder is axially and fixedly penetrated through the inner floating disc. One end of the second connecting pipe away from the second storage cylinder is fixedly provided with a second compensating hose. The top of the high-temperature molten salt tank is fixedly provided with a fourth connecting pipe penetrating through the top layer of the tank. The fourth connecting pipe is fixedly connected to one end of the second compensating hose. The third connecting pipe is used for introducing condensed water, and the fourth connecting pipe is used for discharging steam, or the fourth connecting pipe is used for introducing condensed water, and the third connecting pipe is used for discharging steam.

[0019] Further, the molten salt energy storage heat exchange device further includes a reversing valve arranged on the top of the top layer of the tank. The reversing valve includes: a valve housing. On one side of the valve housing close to the top layer of the tank, a first bottom joint and a second bottom joint are fixedly arranged side by side. The lower end of the first bottom joint is fixedly communicated with the third connecting pipe. The lower end of the second bottom joint is fixedly communicated with the fourth connecting pipe. On one side of the valve housing away from the high-temperature molten salt tank, a water inlet head and a steam joint are fixedly arranged side by side. The water inlet head is vertically opposite to the second bottom joint. The steam joint is vertically opposite to the first bottom joint. A valve core is arranged inside the valve housing. There are three groups of valve holes on the valve core. The first group of valve holes includes a vertical valve hole 1 and a vertical valve hole 2. The vertical valve hole 1 can conduct the steam joint and the first bottom joint. The vertical valve hole 2 can conduct the water inlet head and the second bottom joint. The second group of valve holes includes two exhaust valve holes. The two exhaust valve holes can conduct the steam channel and cut off the water flow channel. The third group of valve holes includes an inclined hole 1 and an inclined hole 2. The inclined hole 1 can conduct the steam joint and the second bottom joint. The inclined hole 2 can conduct the water inlet head and the first bottom joint. A driving cylinder is arranged at one end of the valve housing. The telescopic movement of the piston rod of the driving cylinder can push and pull the valve core, so that the three groups of valve holes can work in sequence.

[0020] Further, the molten salt energy storage heat exchange device further includes a steam drum. The steam drum is arranged above the reversing valve and is used for feeding water to the water inlet head and removing water from the steam discharged from the steam joint. The steam drum includes: a housing arranged above the reversing valve. A centrifugal water separator is arranged side by side inside the housing. A water supply joint is arranged on one side of the housing close to the centrifugal water separator, and the water supply joint is arranged along the tangent direction of the centrifugal water separator. A water supply pipe is connected to the water supply joint, and the water supply pipe is fixedly communicated with the steam turbine feed water module. A steam exhaust port is arranged on the top wall of the housing and is vertically opposite to the centrifugal water separator. A steam exhaust pipe is connected to the steam exhaust port, and the steam exhaust pipe is fixedly communicated with the high-pressure cylinder and the intermediate-pressure cylinder.

[0021] Further, the centrifugal water remover includes: an inner cylinder, a lower extension part II is integrally provided at the lower end of the inner cylinder, the lower end of the lower extension part II is fixed to the bottom surface of the outer shell, and an upper extension part II is provided at the upper end of the inner cylinder; a water receiving wheel, the water receiving wheel is rotationally assembled outside the upper extension part II, and an upper extension part I is provided at the upper end of the water receiving wheel; a conical wire mesh, the conical wire mesh is located inside the inner cylinder, a rotating shaft is fixedly provided in the middle of the conical wire mesh, and the upper end of the rotating shaft is fixedly connected to the upper extension part I through spokes; a conical part is integrally provided at the lower end inside the inner cylinder, and a drain hole I is opened on one side of the inner cylinder; a steam inlet pipe is installed on one side of the lower extension part II, and the other end of the steam inlet pipe is fixedly connected to a steam joint; a drain hole II is provided on one side of the lower extension part II; the water entering the outer shell through the water supply joint enters the reversing valve through the water inlet head.

[0022] Further, an overflow hole is opened on one side of the outer shell, and the height of the overflow hole is lower than that of the drain hole II; a connecting rod passes through the overflow hole, a sealing plate I is fixedly provided on the side of the connecting rod inside the outer shell, and a sealing plate II is fixedly provided on the side of the connecting rod outside the outer shell; one end of the connecting rod is fixedly connected to the piston rod of the driving cylinder; when the vertical valve hole I and the vertical valve hole II are working, the sealing plate I blocks the overflow hole; when the emptying valve hole is working, the overflow hole is in an open state; when the inclined hole I and the inclined hole II are working, the sealing plate II blocks the overflow hole.

[0023] Further, it further includes a temperature sensor I and a temperature sensor II. The temperature sensor I is fixed at one end of the heat exchange tube group close to the storage cylinder I, and the temperature sensor II is fixed at one end of the heat exchange tube group close to the storage cylinder II, for detecting the temperatures of the high-temperature molten salt on both sides of the heat exchange tube group area; a controller, the detection results of the temperature sensor I and the temperature sensor II are transmitted to the controller, and the controller controls the working of the waste liquid return pump.

[0024] The present invention has the following beneficial effects:

[0025] 1. This molten salt energy storage combined heat and power generation system mainly takes the molten salt energy storage technology as the core. In a heat storage manner, through the comprehensive utilization of valley electricity and abandoned electricity, electricity is converted into heat and stored in molten salt. When the application scenario is mature, high-temperature and high-pressure steam is produced through a heat exchange device, and the steam turbine does work to achieve combined heat and power generation and grid auxiliary services. And it adopts a structure that separates the heat exchange energy storage device from the molten salt electric heater, so that the molten salt flowing through the molten salt electric heater can be heated and then enter the energy storage heat exchange device, so that a small amount of molten salt contacts the molten salt electric heater, which can ensure the heating effect.

[0026] 2. For this molten salt energy storage heat exchange device, on the one hand, the heat exchange tube group is arranged inside the tank body, abandoning the molten salt conveying pipeline that conveys the molten salt in the high-temperature molten salt tank to the heat exchanger, saving the cost of setting up long-distance pipelines and making the device occupy less land. On the other hand, since the heat exchange tube group in this embodiment can change together with the height of the inner floating disc, the heat exchange area of the high-temperature molten salt by the heat exchange tube group is changed, so that the high-temperature molten salt with reduced temperature is discharged immediately, avoiding the situation where the temperature of the molten salt in the low-temperature area is conducted to the high-temperature molten salt in the high-temperature area, resulting in the synchronous reduction of the temperature of the molten salt in the entire high-temperature molten salt tank.

[0027] Of course, it is not necessary for any product implementing the present invention to achieve all the above-mentioned advantages simultaneously. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the molten salt energy storage cogeneration system of the present invention;

[0029] Figure 2 It is an overall view of the molten salt energy storage heat exchange device of the present invention;

[0030] Figure 3 It is a schematic diagram of the internal structure of the molten salt energy storage heat exchange device of the present invention;

[0031] Figure 4 It is a schematic diagram of the structure of the heat insulation board of the present invention;

[0032] Figure 5 It is a schematic diagram of the structure of the heat insulation board without the valve plate assembled of the present invention;

[0033] Figure 6 It is a schematic diagram of the structure of the valve plate of the present invention;

[0034] Figure 7 It is a piping connection diagram of the heat exchange tube group of the present invention;

[0035] Figure 8 For the present invention Figure 3 The schematic diagram of the top layer of the tank without assembly;

[0036] Figure 9 It is an external view of the reversing valve of the present invention;

[0037] Figure 10 It is a schematic diagram of the internal structure of the reversing valve of the present invention;

[0038] Figure 11 It is a schematic diagram of the second state of the reversing valve of the present invention;

[0039] Figure 12 It is a schematic diagram of the first emptying state of the reversing valve of the present invention;

[0040] Figure 13Schematic diagram of the second emptying state of the reversing valve of the present invention;

[0041] Figure 14 Schematic diagram of the first state of the reversing valve of the present invention;

[0042] Figure 15 Schematic diagram of the internal structure of the steam drum of the present invention;

[0043] Figure 16 Schematic diagram of the structure of the centrifugal water separator of the present invention.

[0044] In the figure, 1, low-temperature molten salt tank; 2, molten salt electric heater; 3, energy storage heat exchanger; 4, steam turbine feed water module; 5, reheater; 6, high-pressure cylinder; 7, intermediate-pressure cylinder; 8, low-pressure cylinder; 9, condenser; 10, low-temperature molten salt pump; 11, feed water booster pump; 12, waste liquid return pump;

[0045] 310, high-temperature molten salt tank; 310b, top layer of the tank; 311, pressure relief valve; 312, ladder; 313a, top manhole; 313b, high-level manhole; 313c, low-level manhole; 314, molten salt inlet interface; 315, return hose; 316, light-transmitting hole; 317, tank top ventilation hole; 318, sewage discharge valve;

[0046] 320, steam drum; 321, outer shell; 321a, overflow hole; 322, steam exhaust port; 322a, steam exhaust pipe; 323, feed water joint; 323a, feed water pipe; 324, centrifugal water separator; 3241, water receiving wheel; 3241a, first upward extension; 3242, spoke; 3243, rotating shaft; 3244, conical wire mesh; 3245, inner cylinder; 3245a, second upward extension; 3245b, conical part; 3245c, first drain hole; 3245d, second downward extension; 3245e, second drain hole; 3246, steam inlet pipe;

[0047] 330, internal floating roof; 331, sealing ring; 332, floating drum; 333, floating roof manhole;

[0048] 340, heat exchange tube group; 341, first storage cylinder; 341a, first connecting pipe; 341b, first compensation hose; 341c, third connecting pipe; 342, second storage cylinder; 342a, second connecting pipe; 342b, second compensation hose; 342c, fourth connecting pipe; 343, hanging frame;

[0049] 350, drive cylinder;

[0050] 360, Directional control valve; 361, Valve housing; 362, Water inlet head; 363, Steam joint; 364, Bottom joint one; 365, Bottom joint two; 366, Connecting rod; 367, Spool; 367a, Vertical valve hole one; 367b, Vertical valve hole two; 367c, Drain valve hole; 367d, Oblique hole one; 367e, Oblique hole two;

[0051] 370, Link rod; 370a, Sealing plate one; 370b, Sealing plate two;

[0052] 380, Heat insulation plate; 380a, Through hole; 380b, Perforation; 381, Suspension rod; 382, Valve plate;

[0053] 391, Temperature sensor one; 392, Temperature sensor two. Detailed implementation mode

[0054] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0055] In the description of the present invention, it should be understood that the terms "opening", "upper", "lower", "thickness", "top", "middle", "length", "inner", "periphery", etc. indicating the orientation or position relationship are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the components or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0056] Next, according to Figures 1 - 16 Describe the molten salt energy storage combined heat and power generation system and its molten salt energy storage heat exchange device provided by the embodiments of the present invention.

[0057] On the one hand, the embodiments of the present invention provide a molten salt energy storage combined heat and power generation system. Please refer to Figure 1 .

[0058] This molten salt energy storage combined heat and power generation system includes a low-temperature molten salt tank 1, a molten salt electric heater 2, an energy storage heat exchanger 3, a steam turbine feed water module 4, a reheater 5, a high-pressure cylinder 6, an intermediate-pressure cylinder 7, a low-pressure cylinder 8, and a condenser 9. A low-temperature molten salt pump 10 is provided between the molten salt electric heater 2 and the low-temperature molten salt tank 1. Return pipes are provided on both the energy storage heat exchanger 3 and the reheater 5. A waste liquid return pump 12 is provided on the return pipe. The return pipe is used to send the low-temperature molten salt after heat exchange in the energy storage heat exchanger 3 back into the low-temperature molten salt tank 1;

[0059] It includes a heat storage stage and a heat release stage;

[0060] ① Heat storage stage: During the period when there is curtailment of clean energy such as valley electricity or wind and solar power (unable to be connected to the grid or consumed), the low-temperature molten salt pump 10 starts, and the low-temperature molten salt in the low-temperature molten salt tank 1 flows through the molten salt electric heater 2 under the work of the pump. The molten salt electric heater 2 is used to heat the low-temperature molten salt in the low-temperature molten salt tank 1. The low-temperature molten salt is heated from 290 °C to 560 °C and then stored in the energy storage heat exchanger 3 (high-temperature molten salt tank 310), and the heat storage process is completed.

[0061] The specific flow rate of the low-temperature molten salt pump 10 here is adjusted according to the total amount of molten salt, the heating rate of the molten salt electric heater 2, and the duration of the heat storage process.

[0062] ② Heat release stage: The high-temperature molten salt heated and stored during the heat storage process is stored in the high-temperature molten salt tank 310. After the heat release process starts, a part of the high-temperature molten salt is pumped out by the pump to the reheater 5, and the steam turbine feed water module 4 provides qualified feed water to enter the energy storage heat exchanger 3 for heat exchange to produce high-temperature and high-pressure superheated steam, which flows through the high-pressure cylinder 6 and the intermediate-pressure cylinder 7 respectively, driving the steam turbine to rotate and do work, and driving the generator to generate electricity.

[0063] In the reheater 5, the high-temperature molten salt exchanges heat with the exhaust steam generated by the high-pressure cylinder 6 and the intermediate-pressure cylinder 7 again. The exhaust steam is reheated and pressurized in the reheater 5 and then goes to the low-pressure cylinder 8 to do work. The steam in the low-pressure cylinder 8 passes through the condenser 9. The condenser 9 uses water cooling to condense the steam and recovers the heat in the steam. The condensed feed water returns to the steam turbine feed water module 4. The steam turbine feed water module 4 includes water treatment, deaerator, high and low pressure heaters. The water treated by the steam turbine feed water module 4 forms the heat exchange water capable of exchanging heat with the energy storage heat exchanger 3. The heat exchange water absorbs the heat recovered by the condenser 9 before entering the energy storage heat exchanger 3, thereby raising the water temperature to 50 - 60 °C. The heat exchange water with the increased water temperature is sent into the energy storage heat exchanger 3 by the feed water booster pump 11 for further heat exchange.

[0064] After the high-temperature molten salt completes the above heat exchange function, the temperature drops from 560 °C to 290 °C and becomes low-temperature molten salt. Under the action of the spent liquid return pump 12, it flows through the system molten salt pipeline and is stored in the low-temperature molten salt tank 1, ready for the next heat storage.

[0065] So far, the heat storage and heat release processes of the system of the present invention are completed.

[0066] The parameters of the superheated steam produced by the heat exchange between the molten salt and the system feed water are generally determined according to the technical requirements of the steam turbine feed water module 4 for the superheated steam. Under normal circumstances, the outlet parameters of the superheated steam are 540 °C / 14.42 MPa; the outlet parameters of the steam reheated in the reheater 5 are 540 °C / 2.732 MPa.

[0067] This system can not only generate electricity, but also supply high-quality industrial steam outward by means of steam extraction to achieve combined heat and power generation. By calculating and configuring the core equipment parameters such as the molten salt heat storage capacity, the power of the molten salt electric heater, and the power of the steam turbine system, various results such as the power generation duration of the system, the external steam supply duration, and the steam parameters can be freely combined to adapt to different application scenarios.

[0068] Preferably, the molten salt in the present invention is a binary salt.

[0069] The above processes are all completed under the control of the intelligent control system. According to the feedback of the intelligent terminal hardware data such as temperature, flow rate, and pressure installed in the system, the system automatically runs through the calculation and output of the intelligent control system.

[0070] On the other hand, the embodiment of the present invention also provides a molten salt energy storage heat exchange device. Please refer to Figures 2 - 16 .

[0071] Combined with Figure 2 and Figure 3 , the molten salt energy storage heat exchange device is actually the above-mentioned energy storage heat exchanger 3, which includes a high-temperature molten salt tank 310 for storing high-temperature molten salt. An internal floating disk 330 is provided along the radial section direction of the high-temperature molten salt tank 310. The internal floating disk 330 can float on the liquid surface of the high-temperature molten salt under the buoyancy of the high-temperature molten salt, that is, the height of the internal floating disk 330 is the same as the liquid surface height of the high-temperature molten salt and changes with the change of the liquid surface height of the high-temperature molten salt. A heat exchange tube group 340 is assembled on the side of the internal floating disk 330 close to the high-temperature molten salt. The heat exchange tube group 340 can synchronously change its height with the internal floating disk 330, so that the position of the heat exchange tube group 340 can also change. Since the height of the heat exchange tube group 340 is always located near the liquid surface, the heat exchange tube group 340 can exchange heat with the high-temperature molten salt in the area close to the internal floating disk 330, so that the water in the heat exchange tube group 340 can form high-temperature and high-pressure steam required by the steam turbine.

[0072] Therefore, on the one hand, the molten salt energy storage heat exchange device provided by the embodiment of the present invention directly arranges the heat exchange tube group 340 inside the tank body loaded with high-temperature molten salt, abandons the molten salt conveying pipeline that conveys the molten salt in the high-temperature molten salt tank 310 to the heat exchanger, saves the cost of setting long-distance pipelines, and reduces the floor area of the device; on the other hand, since the heat exchange tube group 340 in this embodiment can change together with the height of the inner floating disc 330, the heat exchange area of the high-temperature molten salt by the heat exchange tube group 340 is changed, so that the high-temperature molten salt with reduced temperature is discharged immediately, avoiding the situation where the temperature of the molten salt in the low-temperature area is conducted to the high-temperature molten salt in the high-temperature area, resulting in the synchronous reduction of the temperature of the molten salt in the entire high-temperature molten salt tank 310 (if the temperature in the entire high-temperature molten salt tank 310 is synchronously reduced per unit time, its overall temperature will become lower and lower over time. By 6-8 pm during the peak electricity consumption period, its heat exchange capacity is seriously insufficient, affecting the work done by the high-pressure cylinder 6, the intermediate-pressure cylinder 7, and the low-pressure cylinder 8, resulting in a serious decline in power generation and insufficient power supply).

[0073] In addition, the inner floating disc 330 here can also reduce the evaporation amount and heat dissipation amount of the high-temperature molten salt.

[0074] Preferably, a guide rod for guiding the inner floating disc 330 is also provided inside the high-temperature molten salt tank 310.

[0075] Preferably, the heat exchange tube group 340 fixes the inner floating disc 330 below through a hanging frame 343.

[0076] Preferably, the inner floating disc 330 is made of stainless steel, and floating cylinders 332 are assembled below it so that the inner floating disc 330 has the ability to float.

[0077] Preferably, a metal sealing ring 331 is provided at the edge of the inner floating disc 330.

[0078] Preferably, at least two groups of floating disc manholes 333 are arranged on the upper surface of the inner floating disc 330. The nominal diameter of the floating disc manholes 333 is generally 500 mm, and a sealing plate is locked on the floating disc manholes 333 through bolts.

[0079] Furthermore, since the high-temperature molten salt in the heat exchange tube group 340 area will gradually become low-temperature molten salt after heat exchange, a return hose 315 is also provided here. One end of the return hose 315 passes through the inner floating disc 330 and contacts the liquid level of the high-temperature molten salt. The other end of the return hose 315 enters the connection waste liquid return pump 12 through a return pipe. When the high-temperature molten salt in the heat exchange tube group 340 area becomes low-temperature molten salt, the waste liquid return pump 12 works, and can convey the lower-temperature molten salt back to the low-temperature molten salt tank 1 through the return hose 315.

[0080] The high-temperature molten salt tank 310 is also provided with a pipeline identical to the return hose 315 and is connected to the reheater 5.

[0081] As Figures 3 - 6 shown, preferably, in order to further avoid the temperature fusion of the molten salt with a gradually decreasing temperature in the heat exchange tube group 340 area and the molten salt that has not yet been heat exchanged in the lower area, a heat insulation plate 380 is fixedly provided on one side of the inner floating disc 330 close to the high-temperature molten salt. The heat exchange tube group 340 is located in the area between the inner floating disc 330 and the heat insulation plate 380. The heat insulation plate 380 divides the molten salt in the high-temperature molten salt tank 310 into two areas of molten salt. One area of the molten salt is the molten salt in the area where the heat exchange tube group 340 is located, and the other area of the molten salt is the molten salt in the remaining areas of the high-temperature molten salt tank 310, so as to reduce the heat exchange of the molten salt in the two areas, thereby ensuring the high-temperature state of the molten salt below the heat insulation plate 380, so that even during the electricity peak period from 6 to 8 pm, its heat exchange capacity is still strong, providing better power supply capacity.

[0082] Preferably, a through hole 380b for the guide rod to pass through is provided on the heat insulation plate 380.

[0083] Preferably, the heat insulation plate 380 is a component with a stainless steel sleeve and a composite polyurethane foam board, and it is fixed below the inner floating disc 330 through a suspension rod 381.

[0084] In fact, the molten salt drawn out by the return hose 315 is the molten salt in the area around the heat exchange tube group 340. As the molten salt is drawn out by the return hose 315, the liquid level of the high-temperature molten salt drops, and both the heat insulation plate 380 and the inner floating disc 330 move downward. During this process, the high-temperature molten salt below the heat insulation plate 380 needs to re-enter the area where the heat exchange tube group 340 is located (that is, the area between the heat insulation plate 380 and the inner floating disc 330). A plurality of groups of through holes 380a are provided on the heat insulation plate 380, and a valve plate 382 is provided in the through holes 380a. When the heat insulation plate 380 and the inner floating disc 330 move downward synchronously, the valve plate 382 is squeezed by the high-temperature molten salt below and rotates in the through holes 380a, so that the through holes 380a are in an open state. The heat insulation plate 380 is opened to allow the molten salt in the remaining areas to enter the area where the heat exchange tube group 340 is located. Of course, when the heat insulation plate 380 is stationary, the valve plate 382 is in a horizontal state, and it closes the through holes 380a to isolate the upper and lower heat.

[0085] Therefore, the molten salt energy storage heat exchange device provided by the embodiment of the present invention can further reduce the temperature exchange of the molten salt in the two areas, thereby reducing the heat loss of the molten salt below, and thus avoiding the situation of a large drop in the power generation capacity in the afternoon and evening.

[0086] Combined with Figure 2 、 Figure 3 and Figure 7As shown in the figure, in order to achieve the inlet of water and the outlet of steam for the heat exchange tube group 340, a first storage cylinder 341 is fixedly provided at one end of the heat exchange tube group 340 here. A first connecting pipe 341a that is fixedly connected to the first storage cylinder 341 is fixedly penetrated along the axial direction on the inner floating disc 330. A first compensating hose 341b is fixedly provided at one end of the first connecting pipe 341a away from the first storage cylinder 341. A third connecting pipe 341c that penetrates through the top layer 310b of the tank is fixedly provided at the top of the high-temperature molten salt tank 310. The third connecting pipe 341c is fixedly connected to one end of the first compensating hose 341b, that is, the third connecting pipe 341c, the first compensating hose 341b, the first connecting pipe 341a, the first storage cylinder 341, and the heat exchange tube group 340 form a connected pipeline.

[0087] A second storage cylinder 342 is fixedly provided at the other end of the heat exchange tube group 340. A second connecting pipe 342a that is fixedly connected to the second storage cylinder 342 is fixedly penetrated along the axial direction on the inner floating disc 330. A second compensating hose 342b is fixedly provided at one end of the second connecting pipe 342a away from the second storage cylinder 342. A fourth connecting pipe 342c that penetrates through the top layer 310b of the tank is fixedly provided at the top of the high-temperature molten salt tank 310. The fourth connecting pipe 342c is fixedly connected to one end of the second compensating hose 342b, that is, the fourth connecting pipe 342c, the second compensating hose 342b, the second connecting pipe 342a, the second storage cylinder 342, and the heat exchange tube group 340 form a connected pipeline.

[0088] The above two connected pipelines have two usage modes: State 1: The third connecting pipe 341c is used to enter condensate water, and the fourth connecting pipe 342c is used to discharge steam; State 2: The fourth connecting pipe 342c is used to enter condensate water, and the third connecting pipe 341c is used to discharge steam; The reason for designing such an inlet and outlet method is that, for example, in the initial state, it is State 2. The fourth connecting pipe 342c enters the water to be heat-exchanged. The water flows through the second compensating hose 342b, the second connecting pipe 342a, and the second storage cylinder 342 and then enters the heat exchange tube group 340. The water exchanges heat with the high-temperature molten salt in the heat exchange tube group 340. During this heat exchange process, Figure 3 and Figure 7 from the perspective of, for the high-temperature molten salt in the area of the heat exchange tube group 340, its left area first exchanges heat with cold water. As the water flow gradually moves to the right, the heat it absorbs is less, resulting in the temperature drop rate of the molten salt in the right area being less than that of the molten salt in the left area. That is, under continuous heat exchange, the heat exchange capacity of the left side gradually weakens. The water starts to be heat-exchanged only when it reaches the right side, and the heat exchange time is greatly shortened, which is very likely to cause the water to be discharged before it forms steam. Therefore, in order to ensure the heat exchange capacity of the high-temperature molten salt in the area of the heat exchange tube group 340, at this time, it is switched to State 1, so that cold water enters the heat exchange tube group 340 from the right side, so that the relatively high-temperature molten salt on the right side can first exchange heat with cold water to ensure the heat exchange effect.

[0089] In addition, it is worth noting that when water passes through the above-mentioned compensation hose 2 342b or compensation hose 1 341b, it can be preheated due to the influence of the temperature in the high-temperature molten salt tank 310, otherwise the steam in the compensation hose 2 342b or compensation hose 1 341b will not cool down.

[0090] In order to realize the switching between the above-mentioned state 1 and state 2, the molten salt energy storage heat exchange device provided in the embodiment of the present invention further includes a reversing valve 360 ​​disposed at the top of the tank top layer 310b, referring to Figure 3 , Figures 7 - 11 shown.

[0091] The reversing valve 360 ​​includes a valve housing 361, and a side of the valve housing 361 close to the tank top layer 310b is fixedly provided with a bottom joint 1 364 and a bottom joint 2 365 arranged side by side. The lower end of the bottom joint 1 364 is fixedly connected to the pipe 3 341c, and the lower end of the bottom joint 2 365 is fixedly connected to the pipe 4 342c, that is, the bottom joint 1 364 forms a passage with the pipe system below the pipe 3 341c, and the bottom joint 2 365 forms a passage with the pipe system below the pipe 4 342c; a side of the valve housing 361 away from the high-temperature molten salt tank 310 is fixedly provided with a water inlet head 362 and a steam joint 363 arranged side by side, the water inlet head 362 is vertically opposite to the bottom joint 2 365, and the steam joint 363 is vertically opposite to the bottom joint 1 364, and a valve core 367 is located in the valve housing 361, and three groups of valve holes are provided on the valve core 367, and the three groups of valve holes are respectively used to form state 1, state 2 and emptying state.

[0092] ① The first group of valve holes is used to form state 2: the valve holes include vertical valve hole 1 367a and vertical valve hole 2 367b. The vertical valve hole 1 367a is used to conduct the steam joint 363 and the bottom joint 1 364, and the vertical valve hole 2 367b is used to conduct the water inlet head 362 and the bottom joint 2 365. At this time, the state is formed. Figure 11 The state shown is Figure 7 From the perspective shown, the heat exchange tube group 340 should have water inlet on the left side and steam exhaust on the right side.

[0093] ② The second group of valve holes is used to form an emptying state. The reason why the emptying state is needed is that, for example, when the state 2 is changed to the state 1, the water inlet on the left side is adjusted to the water inlet on the right side. If the water in the left compensation hose 2 342b is not emptied downward, the water entering from the right side will directly push the water on the left side that has not yet become steam to the pipe 4 342c, which will affect the subsequent steam discharge from the pipe 4 342c. Conversely, when the state 1 is changed to the state 2, this problem will also occur. The valve hole includes an emptying valve hole 367c, and the emptying valve hole 367c has two, one of which is an emptying valve hole 367c in a vertical state, which is used to connect the steam joint 363 and the bottom joint 1 364 (such as Figure 12), this state is used for the water in the left compensation hose 342b to drain downward when changing from state two to state one; the other is the inclined state, which is used to connect the steam joint 363 and the bottom joint two 365 (as Figure 13 ), this state is used for the water in the right compensation hose 341b to drain downward when changing from state one to state two; both of these states maintain the normal discharge of steam.

[0094] ③ The second group of valve holes is used to form state one: the valve holes include the inclined hole one 367d, which is used to conduct the steam joint 363 and the bottom joint two 365, and the inclined hole two 367e is used to conduct the water inlet head 362 and the bottom joint one 364. At this time, Figure 13 the state shown is formed, that is, at this time, from the Figure 7 perspective, the heat exchange tube group 340 should have water inlet on the right side and steam exhaust on the left side.

[0095] In addition, a driving cylinder 350 should also be set. The driving cylinder 350 is located at one end of the valve housing 361. The piston rod of the driving cylinder 350 stretches and retracts to push and pull the valve core 367, so that the three groups of valve holes can work in sequence.

[0096] It should be noted that in actual work, the time required to maintain the emptying state is 30 - 40s. After 30 - 40s, the driving cylinder 350 can act to adjust to state one or state two.

[0097] Combined with Figure 15 and Figure 16 shown, in order to remove moisture from the steam discharged from the steam joint 363, a steam drum 320 is also set here. The steam drum 320 is arranged above the reversing valve 360, and in addition to being used to remove moisture from the steam, the steam drum 320 is also used to supply water to the water inlet head 362.

[0098] It includes a housing 321, a water supply joint 323 and a steam exhaust port 322. The housing 321 is arranged above the reversing valve 360. A centrifugal water separator 324 is arranged side by side in the housing 321. The water supply joint 323 is arranged on one side of the housing 321 close to the centrifugal water separator 324, and the water supply joint 323 is arranged along the tangent direction of the centrifugal water separator 324. A water supply pipe 323a is connected to the water supply joint 323, and the water supply pipe 323a is fixedly communicated with the steam turbine water supply module 4. Thus, the cold water provided by the steam turbine water supply module 4 can rush towards the centrifugal water separator 324 through the water supply joint 323, so that the centrifugal water separator 324 can remove water from the steam.

[0099] Preferably, the steam exhaust port 322 is arranged on the top wall of the housing 321 and is vertically opposite to the centrifugal water separator 324. A steam exhaust pipe 322a is connected to the steam exhaust port 322, and the steam exhaust pipe 322a is fixedly communicated with the high-pressure cylinder 6 and the intermediate-pressure cylinder 7.

[0100] Preferably, the centrifugal water remover 324 mentioned above includes an inner cylinder 3245, a water receiving wheel 3241, and a conical wire mesh 3244.

[0101] A lower extension part two 3245d is integrally provided at the lower end of the inner cylinder 3245, and the lower end of the lower extension part two 3245d is fixed to the bottom surface of the outer shell 321. An upper extension part two 3245a is provided at the upper end of the inner cylinder 3245. A steam inlet pipe 3246 is installed on one side of the lower extension part two 3245d, and the other end of the steam inlet pipe 3246 is fixedly connected to a steam joint 363. The water receiving wheel 3241 is rotatably assembled outside the upper extension part two 3245a. An upper extension part one 3241a is provided at the upper end of the water receiving wheel 3241. The conical wire mesh 3244 is located inside the inner cylinder 3245. A rotating shaft 3243 is fixedly provided in the middle of the conical wire mesh 3244, and the upper end of the rotating shaft 3243 is fixedly connected to the upper extension part one 3241a through spokes 3242. In this embodiment, when the water supply joint 323 impacts the water receiving wheel 3241, the water receiving wheel 3241 drives the conical wire mesh 3244 to rotate through the upper extension part one 3241a and the spokes 3242. The water in the steam entering through the steam inlet pipe 3246 can be intercepted by the conical wire mesh 3244, and the water attached to the conical wire mesh 3244 is separated from the conical wire mesh 3244 outward under the action of centrifugal force.

[0102] Therefore, the air bag 320 in the molten salt energy storage heat exchange device provided by the present invention can quickly remove the moisture in the steam. In addition, since the path of the steam is located inside the inner cylinder 3245 and the path of the cold water is located outside the inner cylinder 3245, the water path and the steam path are completely separated. Compared with the water and gas co-path separation method in the prior art, the situation that the water content in the steam increases due to the water in the water path entering the steam interior can be avoided.

[0103] Preferably, a conical part 3245b is integrally provided at the lower end inside the inner cylinder 3245, and a drain hole one 3245c is opened on one side of the inner cylinder 3245, so that the water separated from the conical wire mesh 3244 under the action of centrifugal force can be discharged through the drain hole one 3245c.

[0104] Preferably, a drain hole two 3245e is provided on one side of the lower extension part two 3245d, so that a small amount of water falling from above the inner cylinder 3245 can be discharged into the outer shell 321 through the drain hole two 3245e.

[0105] In addition, it is worth noting that the water entering the outer shell 321 through the water supply joint 323 enters the reversing valve 360 through the water inlet head 362.

[0106] Combined with Figures 10 - 14As shown, since steam is still discharging when the second group of valve holes form an emptying state for the pipe system, the conical wire mesh 3244 still needs to rotate continuously. Therefore, the water supply pipe 323a also needs to continuously intake water at this time. However, too much water intake will cause water flow to enter the inner cylinder 3245 through the first drainage hole 3245c and the second drainage hole 3245e, resulting in the mixing of the steam path and the water path. Therefore, an overflow hole 321a is provided on one side of the outer shell 321. The height of the overflow hole 321a is lower than that of the second drainage hole 3245e, and the water flow discharged from the overflow hole 321a can be sent back into the steam turbine feed water module 4.

[0107] In the non-emptying state, the overflow hole 321a does not need to be opened (this is because due to the set water intake parameters, the water level in the outer shell 321 will not exceed the height of the second drainage hole 3245e). Therefore, a linkage rod 370 penetrates through the overflow hole 321a. On one side of the linkage rod 370 located inside the outer shell 321, a first sealing plate 370a is fixedly provided, and on one side of the linkage rod 370 located outside the outer shell 321, a second sealing plate 370b is fixedly provided. One end of the linkage rod 370 is fixedly connected to the piston rod of the driving cylinder 350 through a connecting rod 366.

[0108] In this implementation, when the first vertical valve hole 367a and the second vertical valve hole 367b are working, the first sealing plate 370a blocks the overflow hole 321a; when the emptying valve hole 367c is working, the overflow hole 321a is in an open state; when the first inclined hole 367d and the second inclined hole 367e are working, the second sealing plate 370b blocks the overflow hole 321a, achieving the purpose of automatically opening the overflow hole 321a in the above-mentioned emptying state.

[0109] Preferably, sealing gaskets are provided on the sides of the second sealing plate 370b and the first sealing plate 370a close to the overflow hole 321a.

[0110] The molten salt energy storage heat exchange device provided by the embodiment of the present invention further includes a first temperature sensor 391, a second temperature sensor 392 and a controller. The first temperature sensor 391 is fixed at one end of the heat exchange tube group 340 close to the first storage cylinder 341, and the second temperature sensor 392 is fixed at one end of the heat exchange tube group 340 close to the second storage cylinder 342, for detecting the temperatures of the high-temperature molten salt on both sides of the heat exchange tube group 340 area.

[0111] In this implementation, when the detection results of the first temperature sensor 391 and the second temperature sensor 392 meet the set threshold (300 °C), the controller controls the waste liquid return pump 12 to work, so as to extract a certain amount of lower-temperature molten salt from the high-temperature molten salt tank 310.

[0112] The first temperature sensor 391 and the second temperature sensor 392 also have another function, that is, when the temperature difference between the two is greater than 60 °C, the driving cylinder 350 is controlled to work, so that the reversing valve 360 works, and the water inlet end of the heat exchange tube group 340 is adjusted to the steam exhaust end, and the exhaust end is adjusted to the water inlet end.

[0113] It should be noted that the hoses used in the present invention are all stainless steel hoses.

[0114] Preferably, a molten salt inlet interface 314 is provided on the lower side of the high-temperature molten salt tank 310. The molten salt inlet interface 314 is fixed to the pipeline of the molten salt electric heater 2. A lower manhole 313c and a blowdown valve 318 are also provided at the lower position.

[0115] Preferably, a top manhole 313a, a tank top vent hole 317, and a light-transmitting hole 316 are also provided on the tank top layer 310b.

[0116] Preferably, a high manhole 313b and a pressure relief valve 311 are provided at the high position of the high-temperature molten salt tank 310.

[0117] Preferably, a ladder 312 is provided around the high-temperature molten salt tank 310.

[0118] During use (operation), in the initial state, the reversing valve 360 is in state two. The steam turbine feed water module 4 feeds water through the feed water pipe 323a. The water flow enters the outer shell 321 and causes the water receiving wheel 3241 to rotate. The water entering the outer shell 321 passes through the water inlet head 362 into the vertical valve hole two 367b, and then enters the connecting pipe four 342c through the bottom joint two 365. Then it passes through the compensating hose two 342b, the connecting pipe two 342a, and the storage cylinder two 342 in sequence and enters the heat exchange tube group 340. The water in the heat exchange tube group 340 first exchanges heat rapidly with the high-temperature molten salt on the left side. Subsequently, the formed steam passes through the storage cylinder one 341, the connecting pipe one 341a, the compensating hose one 341b, the connecting pipe three 341c, the bottom joint one 364, the vertical valve hole one 367a, the steam joint 363, and the steam inlet pipe 3246 into the inner cylinder 3245, and is dewatered by the conical wire mesh 3244. The dewatered steam enters the high-pressure cylinder 6 and the intermediate-pressure cylinder 7 through the steam exhaust port 322 and the steam exhaust pipe 322a to do work. As the cold water continues to be input into the heat exchange tube group 340, the temperature of the high-temperature molten salt around the heat exchange tube group 340 gradually decreases, especially the high-temperature molten salt on the left side. Until the detected temperature of the temperature sensor two 392 is greater than the detected temperature of the temperature sensor one 391 by 60 °C, the control drive cylinder 350 works. At this time, in the Figure 11 shown state, the valve core 367 moves to the left, forming Figure 12 the shown state. At this time, the water in the left compensating hose two 342b is drained downward (the drainage time is preferably 30 - 40 s). Subsequently, the drive cylinder 350 continues to work, and the valve core 367 continues to move to the right until it forms Figure 14 the shown state. At this time, the water inlet end and the steam exhaust end of the heat exchange tube group 340 are exchanged (at this time, state one is formed).

[0119] In the case of State 1, after the heat exchange tube group 340 exchanges heat for a period of time, when the detected values of the first temperature sensor 391 and the second temperature sensor 392 both reach 300 °C, the controller controls the waste liquid reflux pump 12 to operate, and conveys the molten salt with a decreased temperature back to the interior of the low-temperature molten salt tank 1 for storage.

[0120] As the liquid level in the high-temperature molten salt tank 310 drops, the internal floating disc 330 and the heat insulation plate 380 move downward synchronously.

[0121] The valve plate 382 is squeezed by the high-temperature molten salt below and rotates within the through hole 380a, causing the through hole 380a to be in an open state. The heat insulation plate 380 is opened to allow the molten salt in the remaining area to enter the area where the heat exchange tube group 340 is located. At this time, the heat exchange tube group 340 can exchange heat with the molten salt at a higher temperature again.

[0122] As heat exchange progresses, the temperature of the molten salt on the right side is lower than that of the molten salt on the left side. The driving cylinder 350 extends, causing the reversing valve 360 to change from the Figure 14 state to the Figure 13 state shown. At this time, the water in the first compensation hose 341b on the right side is emptied and drained downward. Subsequently, the valve core 367 continuously moves during operation, and the Figure 11 state shown (State 2) is re-formed.

Claims

1. Molten salt energy storage cogeneration system, characterized in that: It comprises a low-temperature molten salt tank (1), a molten salt electric heater (2), an energy storage heat exchanger (3), a turbine feedwater module (4), a reheater (5), a high-pressure cylinder (6), a medium-pressure cylinder (7), a low-pressure cylinder (8) and a condenser (9), wherein a low-temperature molten salt pump (10) is provided between the molten salt electric heater (2) and the low-temperature molten salt tank (1); The molten salt electric heater (2) is capable of heating the low-temperature molten salt in the low-temperature molten salt tank (1), and the heated high-temperature molten salt enters the energy storage heat exchanger (3); The steam turbine water supply module (4) can supply water to the energy storage heat exchanger (3), so that the water exchanges heat with the high-temperature molten salt and generates steam that can enter the high-pressure cylinder (6) and the medium-pressure cylinder (7) to perform work. The high-temperature molten salt in the energy storage heat exchanger (3) can partially enter the reheater (5); the exhaust steam formed by the high-pressure cylinder (6) and the medium-pressure cylinder (7) can exchange heat with the high-temperature molten salt in the reheater (5), and the exhaust steam is heated and pressurized to enter the low-pressure cylinder (8) to perform work. The condenser (9) can condense the high-temperature gas in the low-pressure cylinder (8), and the generated condensed water enters the steam turbine water supply module (4); The energy storage heat exchanger (3) and the reheater (5) are both provided with a reflux pipe, and the reflux pipe is provided with a spent liquid reflux pump (12). The reflux pipe can return the low-temperature molten salt after heat exchange in the energy storage heat exchanger (3) to the low-temperature molten salt tank (1); The energy storage heat exchanger (3) comprises: A high-temperature molten salt tank (310), wherein high-temperature molten salt is stored in the high-temperature molten salt tank (310); An inner floating plate (330), wherein the inner floating plate (330) is arranged in the high-temperature molten salt tank (310) along a radial section direction of the high-temperature molten salt tank (310), and the height of the inner floating plate (330) changes with the liquid level of the high-temperature molten salt; A heat exchange tube group (340), wherein the heat exchange tube group (340) is assembled on a side of the inner floating plate (330) close to the high-temperature molten salt and changes height synchronously with the inner floating plate (330). The heat exchange tube group (340) can exchange heat with the high-temperature molten salt in a region close to the inner floating plate (330); A return hose (315), one end of which passes through the inner floating plate (330) and contacts the liquid surface of the high-temperature molten salt, and the other end of which passes through the return pipe and enters the spent liquid return pump (12); A heat insulation plate (380) is fixedly provided on one side of the inner floating plate (330) close to the high-temperature molten salt, and the heat exchange tube group (340) is located in the area between the inner floating plate (330) and the heat insulation plate (380); The heat insulation plate (380) divides the molten salt in the high-temperature molten salt tank (310) into two areas of molten salt, wherein the molten salt in one area is the molten salt in the area where the heat exchange tube group (340) is located, and the molten salt in the other area is the molten salt in the remaining areas of the high-temperature molten salt tank (310); The heat insulation plate (380) is provided with a plurality of through holes (380a), and a valve plate (382) is provided in the through hole (380a). The valve plate (382) can rotate in the through hole (380a) to control the through hole (380a) to be in an open or closed state. When the heat insulation plate (380) is opened, molten salt in other areas can enter the area where the heat exchange tube group (340) is located. A storage cylinder 1 (341) is fixedly provided at one end of the heat exchange tube group (340); a pipe 1 (341a) is fixedly passed through the inner floating plate (330) in the axial direction and is in fixed communication with the storage cylinder 1 (341); a compensating hose 1 (341b) is fixedly provided at one end of the pipe 1 (341a) away from the storage cylinder 1 (341); a pipe 3 (341c) is fixedly provided on the top of the high-temperature molten salt tank (310) and passes through the top layer (310b) of the tank; and the pipe 3 (341c) is fixedly connected to one end of the compensating hose 1 (341b); A second storage cylinder (342) is fixedly provided at the other end of the heat exchange tube group (340); a second pipe (342a) is fixedly passed through the inner floating plate (330) along the axial direction and is fixedly connected to the second storage cylinder (342); a second compensation hose (342b) is fixedly provided at one end of the second pipe (342a) away from the second storage cylinder (342); a fourth pipe (342c) is fixedly provided on the top of the high-temperature molten salt tank (310) and passes through the top layer (310b) of the tank; and the fourth pipe (342c) is fixedly connected to one end of the second compensation hose (342b).

2. The molten salt energy storage cogeneration system according to claim 1 is characterized in that: The tank further comprises a reversing valve (360) disposed on the top of the tank top layer (310b), wherein the reversing valve (360) comprises: A valve housing (361), wherein a side of the valve housing (361) close to the tank top layer (310b) is fixedly provided with a bottom joint 1 (364) and a bottom joint 2 (365) arranged side by side, wherein the lower end of the bottom joint 1 (364) is fixedly connected to the pipe 3 (341c), and the lower end of the bottom joint 2 (365) is fixedly connected to the pipe 4 (342c); a side of the valve housing (361) away from the high-temperature molten salt tank (310) is fixedly provided with a water inlet head (362) and a steam joint (363) arranged side by side, wherein the water inlet head (362) is vertically opposite to the bottom joint 2 (365), and the steam joint (363) is vertically opposite to the bottom joint 1 (364); A valve core (367), the valve core (367) being located in the valve housing (361), the valve core (367) being provided with three groups of valve holes, the first group of valve holes comprising a vertical valve hole 1 (367a) and a vertical valve hole 2 (367b), the vertical valve hole 1 (367a) being able to conduct the steam joint (363) and the bottom joint 1 (364), the vertical valve hole 2 (367b) being able to conduct the water inlet head (362) and the bottom joint 2 (365) The second group of valve holes includes two drain valve holes (367c), and the two drain valve holes (367c) can conduct the steam channel and disconnect the water channel; the third group of valve holes includes an inclined hole 1 (367d) and an inclined hole 2 (367e), and the inclined hole 1 (367d) can conduct the steam joint (363) and the bottom joint 2 (365), and the inclined hole 2 (367e) can conduct the water inlet head (362) and the bottom joint 1 (364); A drive cylinder (350) is located at one end of the valve housing (361), and a piston rod of the drive cylinder (350) can push and pull the valve core (367) by extending and retracting.

3. The molten salt energy storage cogeneration system according to claim 2 is characterized in that: It also includes an air bag (320), wherein the air bag (320) is arranged above the reversing valve (360), and the air bag (320) includes: A housing (321), the housing (321) being arranged above the reversing valve (360), and having centrifugal dehydrators (324) arranged side by side in the housing (321); A water supply joint (323), the water supply joint (323) being arranged on a side of the housing (321) close to the centrifugal dehydrator (324), and the water supply joint (323) being arranged along a tangent direction of the centrifugal dehydrator (324), the water supply joint (323) being connected to a water supply pipe (323a), and the water supply pipe (323a) being fixedly connected to a steam turbine water supply module (4); A steam exhaust port (322), the steam exhaust port (322) being arranged on the top wall of the outer shell (321) and vertically opposite to the centrifugal dehydrator (324), the steam exhaust port (322) being connected to a steam exhaust pipe (322a), the steam exhaust pipe (322a) being fixedly connected to the high-pressure cylinder (6) and the medium-pressure cylinder (7).

4. The molten salt energy storage cogeneration system according to claim 3 is characterized in that: The centrifugal dehydrator (324) comprises: An inner cylinder (3245), wherein the lower end of the inner cylinder (3245) is provided with an integral lower extension portion (3245d), the lower end of the lower extension portion (3245d) is fixed to the bottom surface of the outer shell (321), and the upper end of the inner cylinder (3245) is provided with an upper extension portion (3245a); A water receiving wheel (3241), wherein the water receiving wheel (3241) is rotatably assembled outside the second upper extension part (3245a), and the upper end of the water receiving wheel (3241) is provided with the first upper extension part (3241a); A conical wire mesh (3244), the conical wire mesh (3244) being located in the inner cylinder (3245), a rotating shaft (3243) being fixedly arranged in the middle of the conical wire mesh (3244), and an upper end of the rotating shaft (3243) being fixedly connected to an upper extension portion (3241a) via spokes (3242); An integral conical portion (3245b) is provided at the lower end of the inner cylinder (3245), and a drainage hole (3245c) is provided on one side of the inner cylinder (3245); A steam inlet pipe (3246) is installed on one side of the second lower extension portion (3245d), and the other end of the steam inlet pipe (3246) is fixedly connected to a steam joint (363); A second drainage hole (3245e) is provided on one side of the second lower extension portion (3245d); Water that enters the housing (321) through the water supply joint (323) enters the reversing valve (360) through the water inlet head (362).

5. The molten salt energy storage cogeneration system according to claim 4 is characterized in that: An overflow hole (321a) is provided on one side of the housing (321), and the height of the overflow hole (321a) is lower than the height of the second drainage hole (3245e); A connecting rod (370) passes through the overflow hole (321a); ​​a sealing plate 1 (370a) is fixedly provided on the side of the connecting rod (370) located inside the housing (321); and a sealing plate 2 (370b) is fixedly provided on the side of the connecting rod (370) located outside the housing (321); One end of the connecting rod (370) is fixedly connected to the piston rod of the driving cylinder (350); When the vertical valve hole 1 (367a) and the vertical valve hole 2 (367b) are working, the sealing plate 1 (370a) blocks the overflow hole (321a); ​​when the drain valve hole (367c) is working, the overflow hole (321a) is in an open state; when the inclined hole 1 (367d) and the inclined hole 2 (367e) are working, the sealing plate 2 (370b) blocks the overflow hole (321a).

6. The molten salt energy storage cogeneration system according to any one of claims 1 to 5, characterized in that: It also includes a temperature sensor 1 (391) and a temperature sensor 2 (392), wherein the temperature sensor 1 (391) is fixed to one end of the heat exchange tube group (340) close to the storage tube 1 (341), and the temperature sensor 2 (392) is fixed to one end of the heat exchange tube group (340) close to the storage tube 2 (342), and is used to detect the temperature of the high-temperature molten salt on both sides of the heat exchange tube group (340); The detection results of the temperature sensor 1 (391) and the temperature sensor 2 (392) are transmitted to the controller, and the controller controls the operation of the spent liquid reflux pump (12).

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