Compressed air powered system and method

Abstract

This invention provides a compressed air energy supply system and method. The system includes a compressor unit, a first heat exchanger, an air storage device, a heat storage device, a heating device, a regenerative unit, and a control system. The control system comprises an independently controlled air storage control system and a heat storage control system. The compressor unit, the first heat exchanger, the air storage device, and the heat storage device are connected to form a heat storage circulation loop. The heating device is connected to the heat storage device via a heat release pipeline. The regenerative unit recovers the return water from the heating supply and / or the waste heat from the motor cooling to preheat the air drawn into the compressor unit. This invention employs a gas-heat decoupling method, storing the pressure potential energy and compression heat of compressed air separately, achieving independent and flexible control of gas and heat supply in terms of time and scale. Simultaneously, the regenerative unit utilizes internal low-grade waste heat to preheat the intake air in stages, further increasing the compressed exhaust temperature through the heat pump effect, significantly improving the overall energy utilization efficiency of the system.

Description

Technical Field

[0007]

[0001] The present invention relates to the technical field of compressed air energy storage and integrated energy supply, and particularly to a compressed air energy supply system and method. Background Art

[0002] As an important power gas source, compressed air has wide applications in industrial production, manufacturing, and energy storage fields. During the air compression process, mechanical energy is converted into the pressure potential energy of air, and a large amount of heat energy (i.e., compression heat) is generated concomitantly.

[0003] In existing compressed air supply systems, the main objective is usually to obtain a gas source with a specific pressure. Since the air discharged from the compressor unit is at a relatively high temperature, to meet the temperature requirements of subsequent gas-using equipment or gas storage devices, it is usually necessary to cool the high-temperature compressed air through a cooler (such as an air-cooled or water-cooled device). In this process, a large amount of compression heat is often directly dissipated into the surrounding environment through the cooling medium and cannot be effectively utilized.

[0004] Although some existing technologies attempt to recover the heat energy during the compression process, such as using the compression heat to heat process water or generate steam through a heat exchange device. However, in these solutions, the supply of compressed air and the output of heat energy are usually highly coupled. This coupling results in the mutual restriction of the gas supply scale and the heat supply scale during the operation of the system, making it difficult to flexibly switch or independently compensate according to the different demands of the gas and heat loads on the user side at different times. Especially in scenarios where a stable power gas source supply and high-quality heat energy supply need to be satisfied simultaneously, existing systems often lack effective adjustment means to balance the energy distribution between the two, limiting the further improvement of the system's comprehensive energy utilization efficiency.

[0005] In addition, in existing compressed air energy storage systems, the reuse of low-grade waste heat inside the system is often overlooked. For example, after using the compression heat for external heat supply, the formed steam condensate or high-temperature return water still has a certain temperature, and this part of the heat is usually directly discarded; at the same time, a large amount of cooling heat (carried by cooling water or cooling air) is also generated during the operation of the electric motors supporting high-power compressor units. If these low-grade heat energies are directly dissipated, it not only causes energy waste but also leads to the fluctuation of the compressor intake temperature with the environment. Especially in low-temperature environments, the volumetric efficiency of the compressor unit decreases, and the exhaust temperature is difficult to maintain in the high-efficiency heat storage range, limiting the further improvement of the system's comprehensive efficiency. Summary of the Invention

[0001] In view of the above problems, the present invention provides a compressed air energy supply system and method, aiming to solve the technical problem of how to decouple and flexibly control the compressed air supply and heat energy supply in terms of time and scale

[0007] ​The first aspect of this invention provides a compressed air power supply system, comprising: a compressor unit configured to draw in air, compress it, and discharge compressed air; a first heat exchange device having a primary side and a secondary side for mutual heat exchange, wherein the inlet of the primary side is connected to the exhaust port of the compressor unit; a gas storage device connected to the primary side outlet of the first heat exchange device, configured to store compressed air after heat exchange on the primary side, the gas storage device being connected to an external gas supply pipeline for external gas supply; a heat storage device configured to contain a heat transfer and heat storage fluid, connected to the secondary side of the first heat exchange device to form a heat storage circulation loop for the heat transfer and heat storage fluid to circulate; and a heating device connected to the heat storage device via a heat release pipeline. The system comprises: a heat exchanger, configured to receive heat transfer and storage fluid and output heat; a heating device connected to an external heating pipeline for external heat supply; a regenerative unit, equipped with a first preheater and / or a second preheater, the first preheater configured to connect to the return water at the end of the external heating pipeline, and the second preheater configured to connect to the motor cooling circuit of the compressor unit; and a control system, including a gas storage control system and a heat storage control system, the gas storage control system being connected to the gas storage device and the external gas supply pipeline, configured to control the gas supply of the gas storage device, and the heat storage control system being connected to the heat storage device and the heat release pipeline, configured to control the heat release of the heat storage device, wherein the gas storage control system and the heat storage control system are independently controlled. Through the above configuration, this invention utilizes the low-grade waste heat (heat return water and motor cooling heat) within the system to preheat the compressor inlet air. This achieves cascaded utilization of the system's waste heat, reducing thermal pollution. Furthermore, by preheating, the compressor inlet temperature is increased, generating a "heat pump effect," enabling the compressor unit to raise the discharged compressed air to a higher temperature (e.g., stably maintaining it in the high-grade range of 160℃~350℃) at the same pressure ratio, significantly improving the heat storage capacity of the heat storage device and the overall energy conversion efficiency of the system. The system separates the high-temperature, high-pressure energy generated by air compression in the first heat exchanger. The cooled compressed air enters the air storage device, while the heat transfer fluid that has absorbed the heat of compression enters the heat storage device. This invention employs gas-heat decoupling, storing and utilizing the pressure potential energy and heat of compression of the compressed air separately. Through independent air storage control and heat storage control systems, flexible adjustment of air and heat supply in terms of time and scale is achieved, allowing them to operate independently according to actual needs, significantly improving the overall energy utilization efficiency of the system and avoiding the waste of heat of compression. Optionally, the temperature of the compressed air discharged from the compressor unit is 160℃~350℃. By controlling the compressed air within a higher temperature range, higher-grade heat energy can be recovered, thereby improving the heat storage capacity of the heat storage device and the heating quality of the heating device. Optionally, the thermal storage device includes a single-tank thermal storage unit, with water as the heat transfer and storage fluid, and the heating device includes a flash evaporation unit configured to receive the heat transfer and storage fluid, generate steam, and supply heat externally through an external heating pipeline. This scheme utilizes water as the thermal storage medium and generates steam through flash evaporation technology, resulting in a simple system structure and low investment cost. Optionally, the heating device also includes an electric heater and / or a steam compressor. The electric heater is located inside or outside the single-tank heat storage tank and is configured to heat the heat transfer and storage fluid; the steam compressor is located in the external heating pipeline. When the stored heat energy is insufficient or the user requires higher quality steam, electric heating is used to assist in heating or a steam compressor is used to pressurize and improve the quality, thereby improving the flexibility, reliability, and adaptability of the heating supply to different heat demands. Optionally, the thermal storage device includes a cryogenic storage tank and a high-temperature storage tank, with the heat transfer fluid selected from hot water, thermal oil, or molten salt. The secondary inlet of the first heat exchanger is connected to the outlet of the cryogenic storage tank, and the secondary outlet of the first heat exchanger is connected to the inlet of the high-temperature storage tank. The heating device is configured to generate steam through indirect heat exchange between water and the heat transfer fluid. The heating device includes a second heat exchanger and a steam generator. The second heat exchanger has a primary side and a secondary side for mutual heat exchange. The outlet of the high-temperature storage tank is connected to the primary inlet of the second heat exchanger via a heat release pipeline, the primary outlet of the second heat exchanger is connected to the inlet of the cryogenic storage tank, the secondary side of the second heat exchanger is connected to the steam generator, and the steam generator is connected to an external heating pipeline. Using a dual-tank system with indirect heat exchange enables a larger thermal storage capacity and more stable heat output, and higher thermal storage temperatures can be obtained by selecting media such as thermal oil or molten salt.

[0008] Optionally, the gas storage device can be one of a pipeline steel gas storage tank, an underground gas storage facility, or an artificial chamber gas storage facility. By selecting different gas storage methods, the system can cover gas storage needs ranging from conventional to ultra-large scale, thus improving the system's applicability. Optionally, the system also includes a waste heat recovery heat exchanger with a primary side and a secondary side for mutual heat exchange. The primary side of the waste heat recovery heat exchanger is configured to be connected to an external waste heat source, and the secondary side of the waste heat recovery heat exchanger exchanges heat with the pipeline where the compressor unit's air inlet is located, or with the secondary side of the first heat exchange device. By introducing external waste heat, the exhaust temperature of the compressed air or the heat storage grade of the heat transfer fluid is increased by utilizing the heat pump effect, further enhancing the system's energy recovery capability and utilization efficiency. Optionally, it also includes an inlet filter and a silencer located at the air inlet of the compressor unit. Optionally, the gas storage control system includes a pressure regulating valve and a gas supply flow regulating valve, which are located between the gas storage device and the external gas supply pipeline; the heat storage control system includes a temperature sensor, a circulation pump, and a heat release flow regulating valve, which are located on the heat storage circulation loop, and the heat storage device is connected to the heat release pipeline through the heat release flow regulating valve. A second aspect of the present invention also provides a compressed air power supply method, comprising the following steps: a preheating step: recovering the waste heat from the return water at the end of the external heating pipeline, and / or recovering the waste heat carried by the motor cooling water or cooling air of the compressor unit to preheat the air drawn into the compressor unit to increase the final compression temperature; a compression step: the compressor unit draws in air for compression and discharges compressed air; a storage step: the discharged compressed air enters the primary side of a first heat exchanger and exchanges heat with the heat transfer and heat storage fluid flowing through the secondary side of the first heat exchanger, and the compressed air cooled by heat exchange enters the storage device for storage; a heat storage step: the heat transfer and heat storage fluid heated by heat exchange on the secondary side of the first heat exchanger circulates in the heat storage loop and enters the heat storage device for containment and storage; a supply step: the storage control system independently controls the storage device to supply air to the outside through the external supply pipeline; a heating step: the heat storage control system independently controls the heat storage device to release the heat transfer and heat storage fluid to the heating device through the heat release pipeline, the heating device receives the heat transfer and heat storage fluid and outputs heat, and supplies heat to the outside through the external heating pipeline. This method separates the energy of compressed air into pressure energy and thermal energy for separate storage, and uses independent control logic to achieve complete decoupling of air and heat supply in terms of time and scale. It can flexibly adjust the energy supply strategy according to real-time load demand, thereby improving the economic efficiency and energy conversion efficiency of the system operation. Attached Figure Description Figure 1 This is a schematic diagram of a compressed air power supply system provided in the first embodiment of the present invention.

[0009] Figure 2 A schematic diagram of a dual-tank compressed air power supply system for both hot and cold air according to the second embodiment of the present invention.

[0010] Figure 3 A flowchart of a compressed air power supply method provided in the third embodiment of the present invention.

[0011] Reference numerals: 101-Compressor unit, 102-First heat exchanger, 103-Gas storage device, 104-Gas consumption end, 105-Heat storage device, 106-Flash evaporator, 107-Heat consumption end, 108-Gas storage control system, 109-Heat storage control system, 110-Regenerative unit, 201-Low-temperature storage tank, 202-High-temperature storage tank, 203-Steam generator, 204-Second heat exchanger. Detailed Implementation

[0012] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0013] <First Implementation Method> This embodiment provides a compressed air power supply system.

[0014] like Figure 1 As shown, the compressed air power supply system provided in this embodiment mainly includes a compressor unit 101, a first heat exchange device 102, an air storage device 103, a heat storage device 105, a heating device, a heat recovery unit 110, an air storage control system 108, and a heat storage control system 109.

[0015] The compressor unit 101 is configured to draw in air and compress it to a high temperature and high pressure state before discharging it. Preferably, the temperature range of the compressed air discharged by the compressor unit 101 is 160°C to 350°C. The first heat exchange device 102 has a primary side and a secondary side for mutual heat exchange. The primary side inlet of the first heat exchange device 102 is connected to the exhaust port of the compressor unit 101 via a pipeline, and the primary side outlet is connected to the air storage device 103. The air storage device 103 is configured to store the compressed air after heat exchange on the primary side, and it is connected to an external air supply pipeline for supplying air to the outside.

[0016] The secondary side of the first heat exchanger 102 is connected to the heat storage device 105. Specifically, the outlet of the secondary side of the first heat exchanger 102 is connected to the inlet of the heat storage device 105, and the outlet of the heat storage device 105 is connected to the inlet of the secondary side of the first heat exchanger 102 through a circulation pump (not shown in the figure), forming a heat storage circulation loop for the circulation of heat transfer and heat storage fluid. The heat transfer and heat storage fluid operates in a closed circulation loop, resulting in low losses and low maintenance costs.

[0017] The heat storage device 105 is configured to contain the heat transfer and storage fluid. In this embodiment, the heat storage device 105 includes a single-tank heat storage unit, and the heat transfer and storage fluid is pressurized water. The heat storage device 105 is connected to the secondary side of the first heat exchange device 102 to form a heat storage circulation loop for the pressurized water to circulate.

[0018] The heating device includes a flash evaporator 106. The flash evaporator 106 is connected to the heat storage device 105 through a heat release pipeline and is configured to receive the heat transfer and heat storage fluid, generate steam, and supply heat to the heat-consuming end 107 through an external heating pipeline.

[0019] In some embodiments, to ensure continuous operation of the system, the system may also include a water supply pipeline and a water supply pump. One end of the water supply pipeline is connected to an external water source, and the other end is connected to the thermal storage device 105 or its thermal storage circulation loop. When the flash evaporator 106 converts pressurized water into steam and delivers it to the heat-consuming end 107, causing a reduction in the heat transfer fluid in the thermal storage circulation loop, the water supply pump automatically replenishes liquid water into the loop according to the liquid level balance requirements in the thermal storage device 105 to maintain the thermal storage circulation.

[0020] The control system includes a gas storage control system 108 and a heat storage control system 109, which are independently controlled. The gas storage control system 108 is connected between the gas storage device 103 and the external gas supply pipeline, and includes a pressure regulating valve and a gas supply flow regulating valve for regulating the pressure and flow rate of the supplied gas. The heat storage control system 109 is connected to the heat storage device 105 and the heat release pipeline, and includes a temperature sensor and a circulation pump installed in the heat storage circulation loop, as well as a heat release flow regulating valve installed in the heat release pipeline. The heat storage device 105 is connected to the heat release pipeline via the heat release flow regulating valve for regulating the heat release of the heat storage device 105.

[0021] To further utilize the low-grade waste heat within the system and improve system efficiency, the compressed air power supply system provided in this embodiment also includes a heat recovery unit 110. This heat recovery unit 110 can use the following two preheating methods alone or in combination: The first preheating method is preheating with return water from the heating supply. The system is equipped with a first preheater (not shown in the figure), which is essentially a gas-water heat exchanger. The water side of the first preheater is connected in series to the return water pipe of the external heating pipeline after the flash evaporator 106 or the heat-using end 107, while the gas side is located on the intake pipe of the compressor unit 101. The condensate from the steam generated at the heat-using end 107, or the high-temperature return water that has not been completely flash-evaporated, flows through the first preheater before returning to the heat storage device 105 or being discharged, preheating the cold air drawn into the compressor unit 101. This fully utilizes the residual low-grade heat after heating, achieving cascaded energy utilization.

[0022] The second preheating method: motor cooling heat recovery. The system is equipped with a second preheater (not shown in the diagram). The motor of the high-power compressor unit 101 is typically equipped with a water-cooled or air-cooled system. The heat dissipation end of the motor cooling system (such as the cooling water return pipe or hot air exhaust pipe) is connected to the primary side of the second preheater, and the intake pipe of the compressor unit 101 is connected to the secondary side. In this way, the waste heat from the motor, which would normally be dissipated by the cooling tower or fan, is transferred to the inlet air of the compressor unit 101. This not only preheats the intake air but also reduces the load on the motor cooling system.

[0023] Through the preheating of the aforementioned regenerative unit, the compressor intake temperature is effectively increased. Based on the heat pump effect, with the same mechanical work consumed by the compressor unit, the final exhaust temperature is significantly increased, making it easier to stabilize in the high-grade range of 160℃~350℃, thereby greatly improving the heat exchange efficiency of the first heat exchange device 102 and the heat storage density of the heat storage device 105. It should be noted that this regenerative unit can work in conjunction with a waste heat recovery heat exchanger connected to an "external waste heat source," but this embodiment prioritizes the use of "internal waste heat" to maximize the closed-loop efficiency and operational stability of the system.

[0024] The working process of the compressed air power supply system in this embodiment is as follows: During the compression stage, compressor unit 101 compresses air to a high-temperature and high-pressure state of 160℃~350℃. The resulting high-temperature compressed air first enters the primary side of the first heat exchanger 102, transferring its compression heat to the heat transfer and storage fluid (pressurized water) on the secondary side. After being cooled by the heat exchange, the compressed air enters the gas storage device 103 for storage, thus realizing the extraction of pressure energy at the gas storage end. At the same time, the pressurized water absorbs heat on the secondary side of the first heat exchanger 102, its temperature rises, and it returns to the heat storage device 105 for storage in a high-temperature and pressurized state, realizing the extraction of compression heat energy. Through this physical decoupling, pressure energy and thermal energy are stored separately.

[0025] During the supply phase, the gas storage control system 108 independently controls the release of gas through pressure regulating valves and flow regulating valves according to the needs of the gas user 104. Meanwhile, the heat storage control system 109 independently controls the heat release flow regulating valve according to the needs of the heat user 107, sending high-temperature pressurized water into the flash evaporation device 106 for depressurization and flash evaporation to generate steam for external heat supply.

[0026] Through the above-described gas-heat decoupling system configuration, the pressure potential energy of compressed air is stored in the gas storage device 103 for gas supply, while the heat of compression during the compression process is stored in the heat storage device 105 in the form of high-temperature pressurized water for heating. Since the gas storage device 103 and the heat storage device 105 store energy separately, and the two control systems operate independently, the system can perform asymmetric adjustments according to actual gas and heat load fluctuations. For example, during periods of low gas consumption, the compressor unit 101 can continue to operate for heat storage, resolving the coupling contradiction in traditional systems where gas supply and heat recovery must operate synchronously, thus improving the system's operational flexibility and economy.

[0027] It should be noted that the gas storage device 103 in this embodiment is a pipeline steel gas storage tank. Alternatively, the gas storage device 103 can also be an underground gas storage facility or an artificial cavern gas storage facility.

[0028] To further improve heating quality, the heating system can also be equipped with an electric heater for auxiliary heating when heat is insufficient. It should be noted that the electric heater can be installed inside or outside the single-tank heat storage tank and configured to heat the heat transfer and storage fluid. In addition, the heating system may also include a steam compressor installed on the external heating pipeline for pressurizing and upgrading the flash steam. An inlet filter and a silencer can also be installed at the air inlet of the compressor unit 101 to maintain system cleanliness and safe operation.

[0029] As an example, the electric heater can be an immersion heating tube installed inside the single-tank heat storage tank; or, the electric heater can be an external circulation electric heating pipeline or a jacketed heater installed outside the single-tank heat storage tank, as long as it can heat the heat transfer and heat storage fluid, there is no specific limitation on the form of the electric heater.

[0030] The compressed air power supply system may also include a waste heat recovery heat exchanger, which has a primary side and a secondary side for mutual heat exchange. The primary side is connected to an external waste heat source (such as process waste heat from industrial parks, waste heat from power plants, etc.), and the secondary side exchanges heat with the pipeline where the air inlet of the compressor unit 101 is located. The external waste heat preheats the air entering the compressor unit 101, increases the final compression temperature, and generates a heat pump effect. At the same compression ratio, the exhaust temperature can be significantly increased, thereby improving the heat quality in the heat storage device. In addition, the secondary side of the waste heat recovery heat exchanger can also directly exchange heat with the secondary side of the first heat exchange device 102, directly supplementing the heat of the heat transfer and storage fluid.

[0031] This implementation method, through gas-heat decoupling design and independent control system, realizes the classified storage of compressed air pressure energy and compressed heat, solves the problem of mutual restriction between gas supply and heat supply, and improves the flexibility of energy utilization and the overall efficiency of the system.

[0032] <Second Implementation Method> This embodiment provides a compressed air power supply system, the main difference from the first embodiment being the connection form between the heat storage device and the heat supply device.

[0033] like Figure 2 As shown, the compressed air power supply system provided in this embodiment mainly includes a compressor unit 101, a first heat exchange device 102, a gas storage device 103, a low-temperature storage tank 201, a high-temperature storage tank 202, a heating device (including a steam generator 203 and a second heat exchange device 204), a gas storage control system 108, and a heat storage control system 109.

[0034] The outlet of compressor unit 101 is connected to the primary side inlet of first heat exchanger 102 via a pipeline. The primary side outlet of first heat exchanger 102 is connected to the inlet of gas storage device 103 via a pipeline. The outlet of gas storage device 103 is connected to gas supply terminal 104 via an external gas supply pipeline. Gas storage control system 108 is connected to pressure regulating valves and gas supply flow regulating valves on gas storage device 103 and external gas supply pipeline, and is used to independently control the gas storage and gas supply process.

[0035] The secondary inlet of the first heat exchanger 102 is connected to the outlet of the cryogenic storage tank 201 via a pipeline; the secondary outlet is connected to the inlet of the high-temperature storage tank 202 via a pipeline. The cryogenic storage tank 201 and the high-temperature storage tank 202 together constitute a dual-tank thermal storage device. The heat transfer and storage fluid circulates through the first heat exchanger 102, is heated, and then stored in the high-temperature storage tank 202. It should be noted that the heat transfer and storage fluid is selected from hot water, thermal oil, or molten salt. When molten salt is used as the heat transfer and storage fluid, a higher storage temperature range can be achieved, further increasing the storage capacity.

[0036] The heating device of this embodiment generates steam by indirect heat exchange using the heat of a heat transfer and storage fluid. It includes a steam generator 203 and a second heat exchange device 204. The second heat exchange device 204 transfers heat from the heat transfer and storage fluid in the high-temperature storage tank 202 to water, while the steam generator 203 converts the heat-absorbing water into steam. The outlet of the high-temperature storage tank 202 is connected to the primary inlet of the second heat exchange device 204 via a heat release pipeline, and the primary outlet of the second heat exchange device 204 is connected to the inlet of the low-temperature storage tank 201, forming a heat release circulation loop. The secondary inlet of the second heat exchange device 204 is connected to a water supply pipeline, and the secondary outlet is connected to the water inlet of the steam generator 203, used to transport water heated by the second heat exchange device 204 to the steam generator 203. The steam generator 203 is configured to vaporize water to generate steam, and its steam outlet is connected to an external heating pipeline. The thermal storage control system 109 is connected to the low-temperature storage tank 201, the high-temperature storage tank 202, the circulating pump, and the regulating valves on the external heating pipeline, and is used to independently regulate the thermal storage and heat release processes.

[0037] Compared with the method of directly using the heat storage medium (such as pressurized water) to generate steam, the heat of the heat storage fluid is transferred to the feed water through the second heat exchange device 204, and then the feed water is vaporized by the steam generator 203 to generate steam. This achieves mutual isolation between the heat storage circuit and the steam circuit, avoids the heat storage fluid (such as heat transfer oil, molten salt, etc.) from entering the steam system, and improves the safety and reliability of the system operation.

[0038] Similarly, the compressed air power supply system of this embodiment may also include a regenerative unit 110. The regenerative unit 110 includes a first preheater and / or a second preheater, and its connection method is the same as that of the first embodiment: using the waste heat of the return water from the steam generator 203 or the external heating pipeline after the heat-consuming end 107, as well as the cooling heat of the motor of the compressor unit 101, the air at the intake port of the compressor unit 101 is preheated to increase the intake air temperature, generate a heat pump effect, and further improve the exhaust temperature and system efficiency.

[0039] The working process of the compressed air power supply system in this embodiment is as follows: After being compressed to a high temperature and high pressure state within the range of 160℃ to 350℃ by the compressor unit 101, the air enters the primary side of the first heat exchange device 102 and exchanges heat with the heat transfer and storage fluid from the cryogenic storage tank 201. After heat exchange, the temperature of the compressed air decreases, and it enters the gas storage device 103 for storage. Under the control of the gas storage control system 108, compressed air is supplied according to the needs of the gas consumption end 104.

[0040] Simultaneously, the heat transfer and storage fluid on the secondary side of the first heat exchanger 102 absorbs the heat of compression, causing its temperature to rise, and enters the high-temperature storage tank 202 for storage. When the heat-consuming end 107 has a steam demand, the high-temperature heat transfer and storage fluid in the high-temperature storage tank 202, under the control of the heat storage control system 109, enters the primary side of the second heat exchanger 204, transferring heat to the feedwater on the secondary side. This causes the feedwater to heat up and enter the steam generator 203, where it is further vaporized to form steam, which is then transported to the heat-consuming end 107 via external heating pipelines. The heat transfer and storage fluid, whose temperature has decreased after heat exchange, returns to the low-temperature storage tank 201, awaiting the next cycle.

[0041] It should be noted that, depending on the actual gas consumption scale and pressure level, compressor unit 101 can adopt a configuration scheme of multi-stage compression, interstage heat exchange and multi-stage heat storage.

[0042] This implementation method, through a dual-tank system (hot and cold) and an indirect heat exchange design, enables greater heat storage capacity, more stable heating, better steam quality, and higher system safety, making it particularly suitable for applications with large-scale heat demand.

[0043] <Third Implementation Method> This embodiment provides a compressed air power supply method, applicable to the compressed air power supply systems in the first and second embodiments.

[0044] like Figure 3 As shown, the compressed air power supply method includes the following steps: Preheating step S0: Recover the waste heat from the return water at the end of the external heating pipeline, and / or recover the waste heat carried by the motor cooling water or cooling air of the compressor unit 101 to preheat the air drawn into the compressor unit 101 to increase the final compression temperature.

[0045] Compression step S1: The compressor unit 101 draws in air, compresses it, and discharges compressed air at 160℃~350℃.

[0046] Gas storage step S2: The discharged compressed air enters the primary side of the first heat exchange device 102 and exchanges heat with the heat transfer and heat storage fluid flowing through the secondary side of the first heat exchange device 102. The compressed air after heat exchange and cooling enters the gas storage device 103 for storage.

[0047] Heat storage step S3: At the same time, the heat transfer and heat storage fluid after the secondary side of the first heat exchange device 102 is heated by heat exchange flows in the heat storage circulation loop and enters the heat storage device 105 (or enters the high temperature storage tank 202) for containment and storage.

[0048] Gas supply step S4: The gas storage control system 108 independently controls the gas storage device 103 to supply gas to the outside through the external gas supply pipeline according to the needs of the gas user 104.

[0049] Heating step S5: At the same time, the thermal storage control system 109 independently controls the thermal storage device to release heat transfer and thermal storage fluid to the heating device through the heat release pipeline according to the heat demand of the heat-consuming end 107. The heating device receives the heat transfer and thermal storage fluid and outputs heat. When a dual-tank structure is adopted, the heat transfer and thermal storage fluid drives the steam generator 203 to generate steam after heat exchange through the second heat exchange device 204, and then supplies heat to the outside through the external heating pipeline.

[0050] The method of this embodiment separates gas and heat during the energy storage stage and controls them independently during the supply stage. The gas storage control system 108 and the heat storage control system 109 can be adjusted according to the real-time load feedback of the gas consumption end 104 and the heat consumption end 107, thereby realizing efficient energy utilization and flexible scheduling.

[0051] As an example, when the gas supply demand exceeds the heating demand: the gas storage control system 108 can increase the opening of the gas supply flow regulating valve and work with the pressure regulating valve to maintain the pressure stability of the external gas supply pipeline, so as to prioritize the high load demand of the gas consumption end 104. At this time, if the heat in the heat storage device 105 (or high-temperature storage tank 202) is sufficient, the heat storage control system 109 will adjust the opening of the heat release flow regulating valve accordingly based on the smaller heating demand; if the compression heat generated by the continuous operation of the compressor unit 101 exceeds the immediate heating demand, the excess heat will be continuously accumulated in the heat storage device through the heat storage circulation loop, thereby realizing more gas production, less heating supply, and waste heat storage.

[0052] As another example, when the heating demand exceeds the gas supply demand: the thermal storage control system 109 increases the opening of the heat release flow regulating valve according to the high load demand of the heat-consuming end 107, increasing the flow rate of the heat transfer and storage fluid entering the flash evaporator 106 (or the second heat exchanger 204) to improve steam production or heating quality. At this time, the gas storage control system 108 reduces or closes the gas supply flow regulating valve according to the smaller gas demand. If the pressure in the gas storage device 103 has reached its upper limit, the control system can instruct the compressor unit 101 to stop, allowing the thermal storage device to independently release the stored heat energy to meet the heating demand; or, if there is still a reserve in the gas storage device 103, the compressor unit 101 can continue to operate to obtain compression heat and store air, achieving more heating, less gas production, and pressure potential energy storage.

[0053] The above are merely optional embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A compressed air power supply system, characterized in that, include: The compressor unit is configured to draw in air, compress it, and then discharge the compressed air. The first heat exchange device has a primary side and a secondary side for mutual heat exchange, and the inlet of the primary side is connected to the exhaust port of the compressor unit. An air storage device is connected to the primary side outlet of the first heat exchange device and is configured to store compressed air after heat exchange on the primary side. The air storage device is connected to an external air supply pipeline for supplying air to the outside. A heat storage device is configured to contain heat transfer and heat storage fluid, and is connected to the secondary side of the first heat exchange device to form a heat storage circulation loop for the heat transfer and heat storage fluid to circulate. The heating device is connected to the heat storage device through a heat release pipeline and is configured to receive the heat transfer and heat storage fluid and output heat. The heating device is connected to an external heating pipeline for supplying heat to the outside. The regenerative unit is equipped with a first preheater and / or a second preheater. The first preheater is configured to be connected to the return water at the end of the external heating pipeline, and the second preheater is configured to be connected to the motor cooling circuit of the compressor unit. The control system includes a gas storage control system and a heat storage control system. The gas storage control system is connected to the gas storage device and the external gas supply pipeline and is configured to control the gas supply of the gas storage device. The heat storage control system is connected to the heat storage device and the heat release pipeline and is configured to control the heat release of the heat storage device. The gas storage control system and the heat storage control system are controlled independently of each other.

2. The compressed air power supply system as described in claim 1, characterized in that, The temperature of the compressed air discharged by the compressor unit is 160℃~350℃.

3. The compressed air power supply system as described in claim 1, characterized in that, The heat storage device includes a single-tank heat storage unit, the heat transfer and storage fluid is water, and the heating device includes a flash evaporation device configured to receive the heat transfer and storage fluid, generate steam, and supply heat to the outside through the external heating pipeline.

4. The compressed air power supply system as described in claim 3, characterized in that, The heating device further includes an electric heater and / or a steam compressor. The electric heater is located inside or outside the single-tank heat storage tank and is configured to heat the heat transfer and storage fluid. The steam compressor is located in the external heating pipeline.

5. The compressed air power supply system as described in claim 1, characterized in that, The heat storage device includes a low-temperature storage tank and a high-temperature storage tank, and the heat transfer and storage fluid is selected from hot water, heat transfer oil or molten salt; The secondary inlet of the first heat exchanger is connected to the outlet of the low-temperature storage tank, and the secondary outlet of the first heat exchanger is connected to the inlet of the high-temperature storage tank. The heating device is configured to generate steam through indirect heat exchange between water and the heat transfer and storage fluid. The heating device includes a second heat exchange device and a steam generator. The second heat exchange device has a primary side and a secondary side that exchange heat with each other. The outlet of the high-temperature storage tank is connected to the primary inlet of the second heat exchanger via the heat release pipeline. The primary outlet of the second heat exchanger is connected to the inlet of the low-temperature storage tank. The secondary side of the second heat exchanger is connected to the steam generator. The steam generator is connected to the external heating pipeline.

6. The compressed air power supply system as described in claim 1, characterized in that, The gas storage device is one of the following: pipeline steel gas storage tank, underground gas storage facility, or artificial chamber gas storage facility.

7. The compressed air power supply system as described in claim 1, characterized in that, It also includes a waste heat recovery heat exchanger, which has a primary side and a secondary side that exchange heat with each other. The primary side of the waste heat recovery heat exchanger is configured to be connected to an external waste heat source. The secondary side of the waste heat recovery heat exchanger exchanges heat with the pipeline where the air inlet of the compressor unit is located, or exchanges heat with the secondary side of the first heat exchange device.

8. The compressed air power supply system as described in claim 1, characterized in that, It also includes an inlet filter and a silencer, which are located at the air inlet of the compressor unit.

9. The compressed air power supply system as described in claim 1, characterized in that, The gas storage control system includes a pressure regulating valve and a gas supply flow regulating valve, which are located between the gas storage device and the external gas supply pipeline. The thermal storage control system includes a temperature sensor, a circulation pump, and a heat release flow regulating valve. The temperature sensor and the circulation pump are installed on the thermal storage circulation loop, and the thermal storage device is connected to the heat release pipeline through the heat release flow regulating valve.

10. A compressed air power supply method, applicable to the compressed air power supply system according to any one of claims 1-9, characterized in that, Includes the following steps: Preheating step: Recover the waste heat from the return water at the end of the external heating pipeline, and / or recover the waste heat carried by the motor cooling water or cooling air of the compressor unit to preheat the air drawn into the compressor unit to increase the final compression temperature; Compression step: The compressor unit draws in air, compresses it, and then discharges the compressed air; Gas storage step: The discharged compressed air enters the primary side of the first heat exchange device and exchanges heat with the heat transfer and heat storage fluid flowing through the secondary side of the first heat exchange device. After the compressed air is cooled by heat exchange, it enters the gas storage device for storage. Heat storage step: The heat transfer and heat storage fluid, after being heated by heat exchange on the secondary side of the first heat exchange device, flows in the heat storage circulation loop and enters the heat storage device for containment and storage; Gas supply procedure: The gas storage control system independently controls the gas storage device to supply gas to the outside through the external gas supply pipeline; Heating process: The thermal storage control system independently controls the thermal storage device to release the heat transfer and thermal storage fluid to the heating device through the heat release pipeline. The heating device receives the heat transfer and thermal storage fluid and outputs heat, which is then supplied to the outside through the external heating pipeline.

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