A steam supply system

Abstract

The disclosure provides a steam supply system, comprising: a power cycle unit; a low-temperature heat exchange medium storage tank; a heating unit in communication with the low-temperature heat exchange medium storage tank; an inlet of a high-temperature heat exchange medium storage tank in communication with an outlet of the heating unit; the high-temperature heat exchange medium storage tank is configured to store high-temperature medium; a high-temperature inlet of a first heat exchanger is in communication with an outlet of the high-temperature heat exchange medium storage tank; a high-temperature inlet of a second heat exchanger is in communication with a high-temperature outlet of the first heat exchanger; a high-temperature inlet of a third heat exchanger is in communication with a high-temperature outlet of the second heat exchanger, a high-temperature outlet of the third heat exchanger is in communication with an inlet of the low-temperature heat exchange medium storage tank, and a low-temperature side of the third heat exchanger is configured to provide steam energy. The disclosure realizes efficient energy storage, gradient utilization and flexible distribution by deeply coupling a molten salt heat storage system, a supercritical power cycle unit and a steam supply unit, can simultaneously output electric energy and high-temperature steam, and significantly improves the comprehensive energy utilization efficiency and operation economy of the system.

Description

Technical Field

[0001] This disclosure relates to the field of energy storage and utilization technology, and more specifically, to a steam supply system. Background Technology

[0002] With the increasing proportion of renewable energy and the deepening of energy structure transformation, addressing the mismatch between energy supply and demand in time and space has become increasingly prominent. Thermal energy storage technology, especially molten salt thermal energy storage technology, has been widely used in power peak shaving and concentrated solar power generation due to its relatively low cost, large scale, and long lifespan. However, traditional molten salt thermal energy storage systems are typically single-function, used only for power generation or heating, resulting in lower overall energy efficiency and insufficient operational flexibility, making it difficult to adapt to diverse user needs.

[0003] Supercritical carbon dioxide power cycle, as a novel heat-to-work conversion technology, boasts advantages such as high efficiency and compact equipment, making it an important future direction for thermal power generation. While some related technologies combine thermal storage with power generation or heating, these systems often suffer from shallow coupling and insufficient energy cascade utilization. Furthermore, they lack flexible and efficient control methods to simultaneously meet the dynamic demands of both electrical and thermal (steam) load changes. Therefore, developing a combined system capable of efficiently and flexibly achieving energy storage, power output, and stable steam supply is of significant practical importance. Summary of the Invention

[0004] The purpose of this disclosure is to provide a steam supply system that can solve at least one of the aforementioned technical problems. The specific solution is as follows: According to specific embodiments of this disclosure, in one aspect, this disclosure provides a steam supply system, the steam supply system comprising: a low-temperature heat exchange medium storage tank configured to store a low-temperature medium; a heating unit, the inlet of the heating unit being connected to the outlet of the low-temperature heat exchange medium storage tank; a high-temperature heat exchange medium storage tank, the inlet of the high-temperature heat exchange medium storage tank being connected to the outlet of the heating unit; the high-temperature heat exchange medium storage tank being configured to store a high-temperature medium; a first heat exchanger, the high-temperature inlet of the first heat exchanger being connected to the outlet of the high-temperature heat exchange medium storage tank; a second heat exchanger, the high-temperature inlet of the second heat exchanger being connected to the high-temperature outlet of the first heat exchanger; a third heat exchanger, the high-temperature inlet of the third heat exchanger being connected to the high-temperature outlet of the second heat exchanger, and the high-temperature outlet of the third heat exchanger being connected to the inlet of the low-temperature heat exchange medium storage tank; the first heat exchanger being connected to the outlet of the first heat exchange medium storage tank; the second heat exchanger being connected to the outlet of the first heat exchange medium storage tank; the third heat exchanger being connected to the outlet of the first heat exchange medium storage tank; the third heat exchanger being connected to the outlet of the first heat exchange medium storage tank; the third heat exchanger being connected to the outlet of the first heat exchange medium storage tank; the third heat exchanger being connected to the outlet of the first heat exchange medium storage tank; the third heat exchanger being connected to the outlet of the first heat exchange medium storage tank; the fourth heat exchanger being connected to the outlet of the first heat exchange medium storage tank; the fifth heat exchanger being connected to the outlet of the first heat exchange medium storage tank; the sixth heat exchanger being connected to the outlet of the first heat exchange medium storage tank; the seventh ... The three heat exchangers are configured on their low-temperature side to provide the energy required for steam; a power circulation unit includes: a high-temperature turbine 510, the inlet of which is connected to the low-temperature outlet of the first heat exchanger; a fourth heat exchanger, the high-temperature inlet of which is connected to the outlet of the high-temperature turbine 510; a fifth heat exchanger, the high-temperature inlet of which is connected to the high-temperature outlet of the fourth heat exchanger; a sixth heat exchanger, the high-temperature inlet of which is connected to the high-temperature outlet of the fifth heat exchanger; a first compressor, the inlet of which is connected to the high-temperature outlet of the sixth heat exchanger, and the outlet of which is connected to the low-temperature inlet of the fifth heat exchanger; the low-temperature outlet of the fifth heat exchanger is connected to the low-temperature inlet of the fourth heat exchanger; and the low-temperature outlet of the fourth heat exchanger is connected to the low-temperature inlet of the first heat exchanger.

[0005] In an optional embodiment, the power cycle unit further includes a second compressor, the inlet of which is connected to the high-temperature outlet of the fifth heat exchanger, and the outlet of the second compressor is connected to the low-temperature inlet of the fifth heat exchanger.

[0006] In an optional embodiment, the low-temperature side of the sixth heat exchanger uses ambient temperature air and / or water as the cooling medium.

[0007] In an optional embodiment, the power circulation unit further includes: a first diverter, the first diverter being disposed at the high-temperature outlet of the fifth heat exchanger, the first diverter being configured to divert the medium flowing out of the high-temperature outlet of the fifth heat exchanger to the high-temperature inlet of the sixth heat exchanger and the inlet of the second compressor, respectively.

[0008] In an optional embodiment, the power cycle unit further includes: the low-temperature outlet of the second heat exchanger is connected to the low-temperature inlet of the first heat exchanger, and the low-temperature inlet of the second heat exchanger is connected to the outlet of the second compressor.

[0009] In an optional embodiment, the power cycle unit further includes a mixing and diversion pipeline, one end of which is connected to the outlet of the second compressor and the low-temperature outlet of the fifth heat exchanger, respectively, and the other end of which is connected to the low-temperature inlet of the fourth heat exchanger and the low-temperature inlet of the second heat exchanger, respectively.

[0010] In an optional embodiment, a first mixer and a second distributor are provided on the mixing and diversion pipeline. The first mixer is configured to mix the medium flowing out of the outlet of the second compressor and the low-temperature outlet of the fifth heat exchanger, and then divert the medium through the second distributor to the low-temperature inlet of the fourth heat exchanger and the low-temperature inlet of the second heat exchanger.

[0011] In an optional embodiment, the power circulation unit further includes a second mixer located at the low-temperature inlet of the first heat exchanger, the second mixer being configured to mix the media flowing out of the low-temperature outlet of the fourth heat exchanger and the low-temperature outlet of the second heat exchanger.

[0012] In an optional embodiment, the power circulation unit further includes: a first regulating valve, which is disposed between the first distributor and the second compressor; In an optional embodiment, the power circulation unit further includes a second regulating valve, which is located between the mixing and diversion pipeline and the low-temperature inlet of the second heat exchanger.

[0013] In an optional embodiment, the steam supply system further includes a first valve located at the outlet of the cryogenic heat exchange medium storage tank.

[0014] In an optional embodiment, the steam supply system further includes a second valve located between the high-temperature heat exchange medium storage tank and the heating unit.

[0015] In an optional embodiment, the steam supply system further includes a third valve located at the outlet of the high-temperature heat exchange medium storage tank.

[0016] In an optional embodiment, the steam supply system further includes a fourth valve located between the cryogenic heat exchange medium storage tank and the third heat exchanger.

[0017] In an optional embodiment, the steam supply system further includes a first molten salt pump, which is located between the cryogenic heat exchange medium storage tank and the heating unit.

[0018] In an optional embodiment, the steam supply system further includes a second molten salt pump, which is located between the high-temperature heat exchange medium storage tank and the first heat exchanger.

[0019] In an optional embodiment, the steam supply system further includes a steam supply unit that obtains energy through the third heat exchanger.

[0020] In an optional embodiment, the steam supply unit includes a gas-liquid separator, the inlet of which is connected to the low-temperature outlet of the third heat exchanger, and the gas-liquid separator is configured to output steam.

[0021] In an optional embodiment, the steam supply unit further includes a pump, the inlet of which is connected to the liquid outlet of the gas-liquid separator.

[0022] In an optional embodiment, the steam supply unit further includes a throttling valve located between the low-temperature outlet of the third heat exchanger and the inlet of the gas-liquid separator.

[0023] In one alternative embodiment, the heating unit is an electric heater.

[0024] Compared with the prior art, the above-described solutions of this disclosure have at least the following beneficial effects: This disclosure achieves efficient energy storage, cascaded utilization, and flexible allocation by deeply coupling the molten salt thermal energy storage subsystem, the supercritical power cycle unit, and the steam supply unit. It can simultaneously output electrical energy and high-temperature steam, significantly improving the overall energy utilization efficiency and operational economy of the system. Attached Figure Description

[0025] Figure 1 A schematic diagram of a steam supply system according to an embodiment of the present disclosure is shown.

[0026] Figure label: 100: Low-temperature heat exchange medium storage tank; 200: Heating unit; 300: High-temperature heat exchange medium storage tank; 410: First heat exchanger; 420: Second heat exchanger; 430: Third heat exchanger; 500: Power cycle unit; 510: High-temperature turbine; 521: Fourth heat exchanger; 522: Fifth heat exchanger; 523: Sixth heat exchanger; 531: First compressor; 532: Second compressor; 541: First distributor; 542: Second distributor; 551: First mixer; 552: Second mixer; 561: First regulating valve; 562: Second regulating valve; 610: First valve; 620: Second valve; 630: Third valve; 640: Fourth valve; 710: First molten salt pump; 720: Second molten salt pump; 800: Steam supply unit; 810: Gas-liquid separator; 820: Pump; 830: Throttling valve. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of this disclosure clearer, the disclosure will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this disclosure, and not all of them. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0028] The terminology used in the embodiments of this disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of this disclosure. The singular forms “a,” “the,” and “the” as used in the embodiments of this disclosure and the appended claims are also intended to include the plural forms, and “multiple” generally includes at least two unless the context clearly indicates otherwise.

[0029] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0030] It should be understood that although the terms first, second, third, etc., may be used to describe structures in the embodiments of this disclosure, these structures should not be limited to these terms. These terms are only used to distinguish different structures. For example, without departing from the scope of the embodiments of this disclosure, a first component may also be referred to as a second component, and similarly, a second component may also be referred to as a first component.

[0031] Depending on the context, the words “if” or “suppose” as used here can be interpreted as “when” or “in response to determination” or “in response to detection.” Similarly, depending on the context, the phrases “if determination” or “if detection (of the stated condition or event)” can be interpreted as “when determination” or “in response to determination” or “when detection (of the stated condition or event)” or “in response to detection (of the stated condition or event).”

[0032] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the article or device that includes said element.

[0033] In related technologies, molten salt thermal energy storage systems typically have a single function, either solely for power generation or solely for heating. The overall energy utilization efficiency of these systems needs improvement, and their operational flexibility is insufficient, making it difficult to adapt to diverse user needs. While schemes combining thermal energy storage with power generation or heating exist, the system coupling is often shallow, energy cascade utilization is inadequate, and there is a lack of flexible and efficient control methods to simultaneously meet the dynamic changes in both electrical and thermal (steam) loads. Therefore, developing a combined system capable of efficiently and flexibly achieving energy storage, power output, and stable steam supply is of significant practical importance.

[0034] To address at least one of the aforementioned technical problems, this disclosure provides a steam supply system comprising: a low-temperature heat exchange medium storage tank 100 configured to store a low-temperature medium; a heating unit 200, the inlet of which is connected to the outlet of the low-temperature heat exchange medium storage tank 100; and a high-temperature heat exchange medium storage tank 300, the inlet of which is connected to the outlet of the heating unit 200; the high-temperature heat exchange medium storage tank 300... Configuration 0 is for storing high-temperature media; a first heat exchanger 410, the high-temperature inlet of the first heat exchanger 410 being connected to the outlet of the high-temperature heat exchange medium storage tank 300; a second heat exchanger 420, the high-temperature inlet of the second heat exchanger 420 being connected to the high-temperature outlet of the first heat exchanger 410; a third heat exchanger 430, the high-temperature inlet of the third heat exchanger 430 being connected to the high-temperature outlet of the second heat exchanger 420, and the high-temperature outlet of the third heat exchanger 430 being connected to the inlet of the low-temperature heat exchange medium storage tank 100, wherein... The low-temperature side of the third heat exchanger 430 is configured to provide the energy required for steam; a power circulation unit 500 includes: a high-temperature turbine 510, the inlet of which is connected to the low-temperature outlet of the first heat exchanger 410; a fourth heat exchanger 521, the high-temperature inlet of which is connected to the outlet of the high-temperature turbine 510; a fifth heat exchanger 522, the high-temperature inlet of which is connected to the high-temperature outlet of the fourth heat exchanger 521; and a sixth heat exchanger 5... 23. The high-temperature inlet of the sixth heat exchanger 523 is connected to the high-temperature outlet of the fifth heat exchanger 522; the inlet of the first compressor 531 is connected to the high-temperature outlet of the sixth heat exchanger 523, and the outlet of the first compressor 531 is connected to the low-temperature inlet of the fifth heat exchanger 522; the low-temperature outlet of the fifth heat exchanger 522 is connected to the low-temperature inlet of the fourth heat exchanger 521; the low-temperature outlet of the fourth heat exchanger 521 is connected to the low-temperature inlet of the first heat exchanger 410. The steam supply system of this disclosure consists of three systems: a molten salt heat storage and release unit (mainly including: the low-temperature heat exchange medium storage tank 100, the heating unit 200, the high-temperature heat exchange medium storage tank 300, the first heat exchanger 410, the second heat exchanger 420 and the third heat exchanger 430), a supercritical carbon dioxide power cycle (power cycle unit 500), and a steam supply unit 800. During the heat storage stage, the low-temperature molten salt is heated by electric heating and then stored in the high-temperature heat exchange medium storage tank 300. During the energy release stage, the high-temperature molten salt flows sequentially through a three-stage molten salt heat exchanger, driving a power cycle to generate electricity, while simultaneously heating feedwater to produce steam for users. The system controls the direction and flow rate of the molten salt through regulating valves, realizing combined electricity-heat-steam production and flexible load adjustment, with advantages of high efficiency, safety, and high overall energy efficiency.

[0035] The optional embodiments of this disclosure are described in detail below with reference to the accompanying drawings.

[0036] Figure 1 A schematic diagram of a steam supply system according to an embodiment of the present disclosure is shown. Figure 1 As shown, according to a specific embodiment of this disclosure, in one aspect, a steam supply system is provided, the steam supply system comprising: a low-temperature heat exchange medium storage tank 100, the low-temperature heat exchange medium storage tank 100 being configured to store a low-temperature medium; a heating unit 200, the inlet of the heating unit 200 being connected to the outlet of the low-temperature heat exchange medium storage tank 100; and a high-temperature heat exchange medium storage tank 300, the inlet of the high-temperature heat exchange medium storage tank 300 being connected to the outlet of the heating unit 200; the high-temperature heat exchange medium storage tank 300 being configured to store a low-temperature medium; For storing high-temperature media: a first heat exchanger 410, the high-temperature inlet of which is connected to the outlet of the high-temperature heat exchange medium storage tank 300; a second heat exchanger 420, the high-temperature inlet of which is connected to the high-temperature outlet of the first heat exchanger 410; and a third heat exchanger 430, the high-temperature inlet of which is connected to the high-temperature outlet of the second heat exchanger 420, and the high-temperature outlet of which is connected to the inlet of the low-temperature heat exchange medium storage tank 100. The low-temperature side of heat exchanger 430 is configured to provide the energy required for steam; a power circulation unit 500 includes: a high-temperature turbine 510, the inlet of which is connected to the low-temperature outlet of the first heat exchanger 410; a fourth heat exchanger 521, the high-temperature inlet of which is connected to the outlet of the high-temperature turbine 510; a fifth heat exchanger 522, the high-temperature inlet of which is connected to the high-temperature outlet of the fourth heat exchanger 521; and a sixth heat exchanger 52... 3. The high-temperature inlet of the sixth heat exchanger 523 is connected to the high-temperature outlet of the fifth heat exchanger 522; the inlet of the first compressor 531 is connected to the high-temperature outlet of the sixth heat exchanger 523, and the outlet of the first compressor 531 is connected to the low-temperature inlet of the fifth heat exchanger 522; the low-temperature outlet of the fifth heat exchanger 522 is connected to the low-temperature inlet of the fourth heat exchanger 521; the low-temperature outlet of the fourth heat exchanger 521 is connected to the low-temperature inlet of the first heat exchanger 410. The power circulation unit 500 uses carbon dioxide as the circulating working fluid, and the cold side of the sixth heat exchanger 523 can use ambient temperature air or water as the cooling medium. This disclosure achieves efficient energy storage, cascade utilization, and flexible distribution by deeply coupling the molten salt thermal energy storage subsystem, the supercritical power circulation unit 500, and the steam supply unit 800, which can simultaneously output electrical energy and high-temperature steam, significantly improving the overall energy utilization efficiency and operating economy of the system.

[0037] The high-temperature molten salt in the molten salt heat storage and release unit transfers heat to the supercritical CO2 power circulation medium (the medium of the power circulation unit 500 can be supercritical CO2) in the first heat exchanger 410. The heated supercritical CO2 enters the high-temperature turbine 510, expands and does work, and drives the electric generator to generate electricity. The exhaust gas from the outlet of the high-temperature turbine 510 flows sequentially through the hot side of the fourth heat exchanger 521 and the fifth heat exchanger 522.

[0038] In some embodiments, the heating unit 200 may be an electric heater. It should be noted that the heating unit 200 may heat molten salt in various ways, including but not limited to molten salt electric heaters (using off-peak electricity or renewable energy), high-temperature steam generated by boilers, or various industrial waste heat / waste heat, or a combination of the above methods.

[0039] In some embodiments, the high-temperature turbine 510 has a turbine structure. In an optional embodiment, the first compressor 531 is a turbine compressor.

[0040] In some embodiments, the power cycle unit 500 further includes a second compressor 532, the inlet of which is connected to the high-temperature outlet of the fifth heat exchanger 522, and the outlet of which is connected to the low-temperature inlet of the fifth heat exchanger 522. In an optional embodiment, the second compressor 532 is a turbine compressor.

[0041] In some embodiments, the low-temperature side of the sixth heat exchanger 523 uses ambient temperature air and / or water as the cooling medium.

[0042] In some embodiments, the power circulation unit 500 further includes a first diverter 541, which is located at the high-temperature outlet of the fifth heat exchanger 522. The first diverter 541 is configured to divert the medium flowing out of the high-temperature outlet of the fifth heat exchanger 522 to the high-temperature inlet of the sixth heat exchanger 523 and the inlet of the second compressor 532, respectively. The exhaust gas from the high-temperature turbine 510 is diverted after passing through the fourth heat exchanger 521 and the fifth heat exchanger 522: one stream is compressed by the main first compressor 531 and returned to the fifth heat exchanger 522; the other stream is compressed by the second compressor 532 and mixed with the main compressed fluid, and finally flows back to the first heat exchanger 410.

[0043] In some embodiments, the power circulation unit 500 further includes: the low-temperature outlet of the second heat exchanger 420 is connected to the low-temperature inlet of the first heat exchanger 410, and the low-temperature inlet of the second heat exchanger 420 is connected to the outlet of the second compressor 532.

[0044] In some embodiments, the power circulation unit 500 further includes a mixing and diversion pipeline, one end of which is connected to the outlet of the second compressor 532 and the low-temperature outlet of the fifth heat exchanger 522, respectively, and the other end of which is connected to the low-temperature inlet of the fourth heat exchanger 521 and the low-temperature inlet of the second heat exchanger 420, respectively.

[0045] In some embodiments, a first mixer 551 and a second distributor 542 are provided on the mixing and diversion pipeline. The first mixer 551 is configured to mix the medium flowing out of the outlet of the second compressor 532 and the low-temperature outlet of the fifth heat exchanger 522, and then divert the medium through the second distributor 542 to the low-temperature inlet of the fourth heat exchanger 521 and the low-temperature inlet of the second heat exchanger 420.

[0046] In some embodiments, the power circulation unit 500 further includes a second mixer 552, which is disposed at the low-temperature inlet of the first heat exchanger 410 and configured to mix the media flowing out of the low-temperature outlet of the fourth heat exchanger 521 and the low-temperature outlet of the second heat exchanger 420.

[0047] In some embodiments, the power circulation unit 500 further includes a first regulating valve 561, which is disposed between the first distributor 541 and the second compressor 532. In an optional embodiment, the power circulation unit 500 further includes a second regulating valve 562, which is disposed between the mixing and distribution pipeline and the low-temperature inlet of the second heat exchanger 420.

[0048] The medium flowing from the high-temperature outlet of the fifth heat exchanger 522 enters the first distributor 541 and is divided into two streams. One stream enters the second compressor 532 via the first regulating valve 561, and after being pressurized, enters the first mixer 551. The other stream enters the sixth heat exchanger 523 (with ambient air or water as the cold source) for cooling, and then enters the first compressor 531 for compression. The compressed medium then flows through the cold side of the fifth heat exchanger 522 for preheating, and subsequently also enters the first mixer 551. After the two streams are mixed in the first mixer 551, they enter the second distributor 542 and are divided into two streams again. One stream enters the second heat exchanger 420 via the second regulating valve 562 for further heating, and then enters the second mixer 552. The other stream enters the cold side of the fourth heat exchanger 521, is heated by the exhaust gas from the high-temperature turbine 510, and then also enters the second mixer 552. After the two media are mixed in the second mixer 552, they enter the first heat exchanger 410 and are heated by the high-temperature molten salt, completing a complete power cycle.

[0049] In some embodiments, the steam supply system further includes: a first valve 610, which is located at the outlet of the low-temperature heat exchange medium storage tank 100. In an optional embodiment, a second valve 620 is located between the high-temperature heat exchange medium storage tank 300 and the heating unit 200. In an optional embodiment, a third valve 630 is located at the outlet of the high-temperature heat exchange medium storage tank 300. In an optional embodiment, a fourth valve 640 is located between the low-temperature heat exchange medium storage tank 100 and the third heat exchanger 430. The power cycle subsystem uses supercritical carbon dioxide as the medium, and each system switches between the energy storage stage and the energy release stage through valve assemblies (the first valve 610, the second valve 620, the third valve 630, and the fourth valve 640). The valve assembly's on / off states are mutually exclusive, and the energy storage stage and the energy release stage are isolated by controlling the valve's on / off state.

[0050] Energy storage stage: Open the first valve 610 and the second valve 620, close the third valve 630 and the fourth valve 640, start the first molten salt pump 710 and the heating unit 200, heat the low-temperature molten salt and store it in the high-temperature heat exchange medium storage tank 300; Energy release stage: Open the third valve 630 and the fourth valve 640, close the first valve 610 and the second valve 620, start the second molten salt pump 720, and release heat through each heat exchanger in sequence, driving the power cycle to generate electricity and simultaneously supply steam. By adjusting the opening of the first regulating valve 561 and the second regulating valve 562, the flow rate of the circulating medium is dynamically allocated to adjust: the power generation power of the power cycle unit 500; and the steam output or temperature of the steam subsystem, to achieve matching of electricity and heat output demand.

[0051] The steam supply system disclosed herein involves an energy storage phase and an energy release phase. In the energy storage phase, the molten salt electric heater operates independently; in the energy release phase, the power cycle unit 500 converts thermal energy into electrical energy for output, and the steam supply unit 800 supplies high-temperature steam to the user.

[0052] In some embodiments, the steam supply system further includes a first molten salt pump 710, which is disposed between the low-temperature heat exchange medium storage tank 100 and the heating unit 200. In an optional embodiment, the steam supply system further includes a second molten salt pump 720, which is disposed between the high-temperature heat exchange medium storage tank 300 and the first heat exchanger 410. The first molten salt pump 710 and the second molten salt pump 720 are screw-type molten salt pumps 820, suitable for conveying high-temperature molten salt media.

[0053] In some embodiments, the steam supply system further includes a steam supply unit 800, which obtains energy through the third heat exchanger 430.

[0054] In some embodiments, the steam supply unit 800 includes a gas-liquid separator 810, the inlet of which is connected to the low-temperature outlet of the third heat exchanger 430, and the gas-liquid separator 810 is configured to output steam.

[0055] In some embodiments, the steam supply unit 800 further includes a pump 820, the inlet of which is connected to the liquid outlet of the gas-liquid separator 810. The inlet of the pump 820 is also connected to a liquid supply device, which may be a water supply device, a deaerator, etc. The liquid supplied to the inlet of the pump 820 may be ambient temperature water or condensate from a large-scale deaerator, etc. The liquid supplied to the pump 820 is mixed with water from the gas-liquid separator 810 and then pressurized before entering the pump 820. In some embodiments, the pump 820 is a water pump 820. In an optional embodiment, the pump 820 is a turbine centrifugal pump 820.

[0056] In some embodiments, the steam supply unit 800 further includes a throttling valve 830, which is disposed between the low-temperature outlet of the third heat exchanger 430 and the inlet of the gas-liquid separator 810. The throttling valve 830 is used to realize the throttling and pressure reduction process of water; the gas-liquid separator 810 is used to realize the separation of water vapor and liquid water.

[0057] In the steam supply subsystem, ambient temperature water or condensate from the deaerator of the main unit is mixed with water from the gas-liquid separator 810 and then pressurized by the water pump 820. The high-pressure water enters the cold side of the third heat exchanger 430 and is heated into high-temperature, high-pressure water by molten salt. The high-temperature, high-pressure water is throttled and depressurized through the throttling valve 830, becoming a steam-water mixture before entering the gas-liquid separator 810. In the gas-liquid separator 810, saturated steam and saturated water are separated. The steam is sent to the steam header to supply users, while the separated water is mixed with makeup water and re-enters the circulation system.

[0058] The steam supply system disclosed herein combines a power cycle with steam supply, which not only achieves efficient thermoelectric conversion but also supplies steam to users simultaneously, thereby improving the overall energy efficiency of the system.

[0059] The steam supply system disclosed herein: In the energy storage phase, the molten salt electric heater and the heating unit 200 are operated, enabling safe and stable electrothermal conversion, allowing thermal energy to be stored in the high-temperature zone and obtaining higher quality thermal energy. In the energy release phase, the power cycle unit 500 and the steam supply unit 800 are operated in conjunction, not only achieving efficient thermoelectric conversion but also simultaneously supplying steam to users, thus improving the overall energy efficiency of the system. Furthermore, in the energy release phase, by combining the opening degrees of the first regulating valve 561 and the second regulating valve 562, the flow direction of the circulating working fluid in the power cycle can be adjusted, thereby changing the heat exchange between the first heat exchanger 410, the second heat exchanger 4207 and the circulating medium, and thus adjusting the power output capacity of the power cycle unit 500; simultaneously, the change in the heat absorbed by the power cycle will also change the amount or temperature of water vapor generated in the steam supply unit 800, ensuring that the power generation of the power cycle and the steam supply of the steam supply unit 800 dynamically change to match the user's needs.

[0060] This disclosure integrates the power cycle unit 500, the steam supply unit 800, and the molten salt heat storage and release unit. During the energy storage phase, the molten salt electric heater and the heating unit 200 operate, enabling safe and stable electrothermal conversion and allowing heat energy to be stored in the high-temperature zone, resulting in higher quality heat energy. During the energy release phase, the combined operation of the power cycle unit 500 and the steam supply unit 800 not only achieves efficient thermoelectric conversion but also simultaneously supplies steam to users, improving the overall energy efficiency of the system. Furthermore, during the energy release phase, by combining the opening degrees of the first regulating valve 561 and the second regulating valve 562, the flow direction of the circulating working fluid in the power cycle can be adjusted, thereby changing the heat exchange between the first heat exchanger 410, the second heat exchanger 420, and the circulating working fluid, thus adjusting the power output capacity of the power cycle unit 500. Simultaneously, changes in the heat absorbed by the power cycle also alter the amount or temperature of steam generated in the steam supply unit 800, ensuring that the power generation of the power cycle and the steam supply of the steam supply unit 800 dynamically change to match user needs. Overall, it has the following significant advantages: 1. High-efficiency integration and energy cascade utilization: The deep coupling of molten salt thermal storage, high-efficiency supercritical CO2 power generation and steam production realizes the cascade utilization of thermal energy from high temperature to low temperature, which significantly improves the overall energy utilization efficiency of the entire system.

[0061] 2. Flexible operation and bidirectional adjustment: Through a unique supercritical CO2 circulation diversion and recompression structure and valve regulation, the steam supply system can flexibly adjust the output ratio of electricity and steam during the energy release phase, quickly respond to load changes of different users, and enhance the system's adaptability and economy.

[0062] 3. Diverse functions and wide applications: The system has three functions at the same time: large-capacity energy storage, peak power output and stable steam supply. It can be used as a regional integrated energy station and is widely used for energy supply in industrial parks, urban heating and power supply, as well as peak shaving and stable output in conjunction with renewable energy bases.

[0063] 4. Clean and low-carbon: Prioritize the use of renewable energy electricity or industrial waste heat for thermal storage, which can replace part of the fossil fuel consumption when releasing energy, thus helping to reduce carbon emissions and conforming to the direction of green energy development.

[0064] This disclosure aims to protect a steam supply system comprising: a low-temperature heat exchange medium storage tank 100 configured to store a low-temperature medium; a heating unit 200, the inlet of which is connected to the outlet of the low-temperature heat exchange medium storage tank 100; a high-temperature heat exchange medium storage tank 300, the inlet of which is connected to the outlet of the heating unit 200; the high-temperature heat exchange medium storage tank 300 configured to store a high-temperature medium; and a first heat exchanger. Heat exchanger 410, the high-temperature inlet of the first heat exchanger 410 is connected to the outlet of the high-temperature heat exchange medium storage tank 300; the second heat exchanger 420, the high-temperature inlet of the second heat exchanger 420 is connected to the high-temperature outlet of the first heat exchanger 410; the third heat exchanger 430, the high-temperature inlet of the third heat exchanger 430 is connected to the high-temperature outlet of the second heat exchanger 420, and the high-temperature outlet of the third heat exchanger 430 is connected to the inlet of the low-temperature heat exchange medium storage tank 100; the low-temperature outlet of the third heat exchanger 430... The temperature side is configured to provide the energy required for steam; a power circulation unit 500 includes: a high-temperature turbine 510, the inlet of which is connected to the low-temperature outlet of the first heat exchanger 410; a fourth heat exchanger 521, the high-temperature inlet of which is connected to the outlet of the high-temperature turbine 510; a fifth heat exchanger 522, the high-temperature inlet of which is connected to the high-temperature outlet of the fourth heat exchanger 521; and a sixth heat exchanger 523. The high-temperature inlet of the sixth heat exchanger 523 is connected to the high-temperature outlet of the fifth heat exchanger 522; the inlet of the first compressor 531 is connected to the high-temperature outlet of the sixth heat exchanger 523, and the outlet of the first compressor 531 is connected to the low-temperature inlet of the fifth heat exchanger 522; the low-temperature outlet of the fifth heat exchanger 522 is connected to the low-temperature inlet of the fourth heat exchanger 521; the low-temperature outlet of the fourth heat exchanger 521 is connected to the low-temperature inlet of the first heat exchanger 410. The steam supply system disclosed herein consists of three systems: a molten salt heat storage and release unit (mainly including: the low-temperature heat exchange medium storage tank 100, the heating unit 200, the high-temperature heat exchange medium storage tank 300, the first heat exchanger 410, the second heat exchanger 420, and the third heat exchanger 430), a supercritical carbon dioxide power cycle (power cycle unit 500), and a steam supply unit 800. During the heat storage stage, the low-temperature molten salt is heated by electric heating and then stored in the high-temperature heat exchange medium storage tank 300. During the energy release stage, the high-temperature molten salt flows sequentially through a three-stage molten salt heat exchanger, driving a power cycle to generate electricity, while simultaneously heating feedwater to produce steam for users. The system controls the direction and flow rate of the molten salt through regulating valves, realizing combined electricity-heat-steam production and flexible load adjustment, with advantages of high efficiency, safety, and high overall energy efficiency.This disclosure achieves efficient energy storage, cascaded utilization, and flexible allocation by deeply coupling the molten salt thermal energy storage subsystem, the supercritical power cycle unit 500, and the steam supply unit 800. It can simultaneously output electrical energy and high-temperature steam, significantly improving the overall energy utilization efficiency and operational economy of the system.

[0065] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems or apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and relevant parts can be referred to the method section.

[0066] The above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit it. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this disclosure.

Claims

1. A steam supply system, characterized in that, include: A cryogenic heat exchange medium storage tank, wherein the cryogenic heat exchange medium storage tank is configured to store cryogenic media; A heating unit, the inlet of which is connected to the outlet of the low-temperature heat exchange medium storage tank; A high-temperature heat exchange medium storage tank, wherein the inlet of the high-temperature heat exchange medium storage tank is connected to the outlet of the heating unit; the high-temperature heat exchange medium storage tank is configured to store a high-temperature medium; The first heat exchanger has a high-temperature inlet connected to the outlet of the high-temperature heat exchange medium storage tank. The second heat exchanger has a high-temperature inlet connected to the high-temperature outlet of the first heat exchanger. The third heat exchanger has a high-temperature inlet connected to the high-temperature outlet of the second heat exchanger, and the high-temperature outlet of the third heat exchanger is connected to the inlet of the low-temperature heat exchange medium storage tank. The low-temperature side of the third heat exchanger is configured to provide the energy required for steam. A power circulation unit, comprising: A high-temperature turbine 510, the inlet of which is connected to the low-temperature outlet of the first heat exchanger; The fourth heat exchanger is connected to the outlet of the high-temperature turbine 510. The fifth heat exchanger is connected to the high-temperature outlet of the fourth heat exchanger. The sixth heat exchanger is connected to the high-temperature outlet of the fifth heat exchanger. The first compressor has its inlet connected to the high-temperature outlet of the sixth heat exchanger and its outlet connected to the low-temperature inlet of the fifth heat exchanger. The low-temperature outlet of the fifth heat exchanger is connected to the low-temperature inlet of the fourth heat exchanger; the low-temperature outlet of the fourth heat exchanger is connected to the low-temperature inlet of the first heat exchanger.

2. The steam supply system according to claim 1, characterized in that, The power cycle unit also includes: The second compressor has its inlet connected to the high-temperature outlet of the fifth heat exchanger, and its outlet connected to the low-temperature inlet of the fifth heat exchanger.

3. The steam supply system according to claim 1, characterized in that, The low-temperature side of the sixth heat exchanger uses ambient temperature air and / or water as the cooling medium.

4. The steam supply system according to claim 2, characterized in that, The power cycle unit also includes: A first diverter is located at the high-temperature outlet of the fifth heat exchanger and is configured to divert the medium flowing out of the high-temperature outlet of the fifth heat exchanger to the high-temperature inlet of the sixth heat exchanger and the inlet of the second compressor, respectively. A first regulating valve is located between the first distributor and the second compressor.

5. The steam supply system according to claim 2, characterized in that, The power cycle unit also includes: The low-temperature outlet of the second heat exchanger is connected to the low-temperature inlet of the first heat exchanger, and the low-temperature inlet of the second heat exchanger is connected to the outlet of the second compressor.

6. The steam supply system according to claim 5, characterized in that, The power cycle unit also includes: A mixing and diversion pipeline is provided, one end of which is connected to the outlet of the second compressor and the low-temperature outlet of the fifth heat exchanger, respectively, and the other end of which is connected to the low-temperature inlet of the fourth heat exchanger and the low-temperature inlet of the second heat exchanger, respectively.

7. The steam supply system according to claim 6, characterized in that, The mixing and diversion pipeline is equipped with a first mixer and a second diverter. The first mixer is configured to mix the medium flowing out of the outlet of the second compressor and the low-temperature outlet of the fifth heat exchanger, and then divert the medium through the second diverter to the low-temperature inlet of the fourth heat exchanger and the low-temperature inlet of the second heat exchanger.

8. The steam supply system according to claim 5, characterized in that, The power cycle unit also includes: A second mixer is located at the low-temperature inlet of the first heat exchanger and is configured to mix the media flowing out of the low-temperature outlet of the fourth heat exchanger and the low-temperature outlet of the second heat exchanger.

9. The steam supply system according to claim 7, characterized in that, The power cycle unit also includes: The second regulating valve is located between the mixing and diversion pipeline and the low-temperature inlet of the second heat exchanger.

10. The steam supply system according to claim 4, characterized in that, Also includes: The first valve is located at the outlet of the cryogenic heat exchange medium storage tank; The second valve is located between the high-temperature heat exchange medium storage tank and the heating unit. The third valve is located at the outlet of the high-temperature heat exchange medium storage tank; The fourth valve is located between the cryogenic heat exchange medium storage tank and the third heat exchanger.

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