A heat storage and release device and method using water as a medium

Abstract

The application discloses a water-medium heat storage and release device and a heat storage and release method. The heat storage and release device comprises a water tank, a booster water pump, a heat storage heat exchanger and a high-pressure heat storage tank. A first water inlet of the high-pressure heat storage tank is used for inputting water after heat absorption, and a second water inlet is used for inputting another part of water after pressure boosting. When the heat storage and release device stores heat, the water after pressure boosting inputted by the high-pressure heat storage tank is used for condensing water vapor stored in the high-pressure heat storage tank, so as to balance the change of water pressure in the high-pressure heat storage tank caused by the water after heat absorption. When the heat storage and release device releases heat, a water outlet is used for outputting heat storage water, and a steam inlet is used for inputting water vapor, so as to balance the change of water pressure in the high-pressure heat storage tank caused by the output of the heat storage water. The application can maintain the stability of water pressure in the heat storage tank by using the evaporation and condensation change of water, can improve the heat storage effect of the system, and has good safety.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of energy storage, and particularly relates to a water-medium heat storage and release device and a heat storage and release method. BACKGROUND

[0002] The application of energy storage technology can solve the volatility and intermittency of new energy generation to a great extent, effectively solve the technical problem of peak load shifting, and has been paid more and more attention in recent years.

[0003] At present, the commonly used heat storage medium of the existing energy storage system includes water, molten salt and heat conducting oil, and the three kinds of heat storage media all have certain drawbacks. Specifically, when the heat storage temperature level is low, the molten salt will solidify and block the pipeline, which is not conducive to the safe and stable operation of the energy storage system; the heat conducting oil can be applied to a wide temperature range, but it has the drawback of flammability, which threatens the safety of the energy storage system; using water as the heat storage medium can effectively avoid the drawbacks of pipeline blockage and flammability, and has high development potential.

[0004] In the prior art, the following technical defects still exist when water is used as the heat storage medium. The heat storage tank is usually a constant volume container. During the process of discharging the heat storage water to release heat, the amount of heat storage water in the heat storage tank gradually decreases, and the water pressure gradually decreases, which can cause the liquid water to flash into gas, causing a large fluctuation in the pressure in the heat storage tank, affecting the heat storage effect of the energy storage system, and even threatening the safety of the energy storage system.

[0005] In summary, in order to avoid the technical defects of the energy storage system when water is used as the heat storage medium, a new water-medium heat storage and release device is urgently needed. SUMMARY

[0006] The purpose of the present application is to provide a water-medium heat storage and release device and a heat storage and release method to solve one or more of the above technical problems. In the technical solution provided by the present application, the evaporation and condensation of water can maintain the water pressure of the heat storage tank stable, improve the heat storage effect of the system, and have good safety.

[0007] To achieve the above purpose, the following technical solutions are adopted in the present application:

[0008] The present application provides a water-medium heat storage and release device in the first aspect, which comprises:

[0009] A water tank for storing low-temperature and low-pressure water to be heat exchanged;

[0010] A booster water pump for inputting the water output from the water tank and boosting the water, and outputting the boosted water in two parts;

[0011] A heat storage heat exchanger, a cold source heat exchange channel of the heat storage heat exchanger is used for inputting a part of the pressurized water, and outputting water after heat absorption;

[0012] A high-pressure heat storage tank is used for storing water vapor with high temperature and high pressure with preset pressure, the high-pressure heat storage tank is provided with a first water inlet, a second water inlet, a water outlet and a steam inlet, the first water inlet is used for inputting the water after heat absorption, and the second water inlet is used for inputting another part of the pressurized water, when the water medium heat storage and release device stores heat, the pressurized water input into the high-pressure heat storage tank is used for condensing water vapor stored in the high-pressure heat storage tank, so as to balance the change of water pressure in the high-pressure heat storage tank caused by inputting the water after heat absorption, when the water medium heat storage and release device releases heat, the water outlet is used for outputting heat storage water, and the steam inlet is used for inputting water vapor, so as to balance the change of water pressure in the high-pressure heat storage tank caused by outputting the heat storage water.

[0013] Further improvement of the heat storage and release device is that the heat storage and release device further comprises:

[0014] A flash evaporator, a water inlet of the flash evaporator is communicated with the water outlet of the high-pressure heat storage tank, and a steam outlet of the flash evaporator is communicated with the steam inlet of the high-pressure heat storage tank through a steam pump;

[0015] A heat release heat exchanger, a heat source heat exchange channel inlet of the heat release heat exchanger is communicated with the water outlet of the flash evaporator, and a heat source heat exchange channel outlet of the heat release heat exchanger is communicated with the water tank.

[0016] Further improvement of the heat storage and release device is that the heat storage and release device further comprises:

[0017] A water turbine, the water turbine is arranged between the heat release heat exchanger and the water tank, is used for generating power by using water output from the heat source heat exchange channel of the heat release heat exchanger, and inputting water after power generation into the water tank.

[0018] Further improvement of the heat storage and release device is that the high-pressure heat storage tank is further provided with an electric heating device, and the electric heating device is used for heating the high-pressure heat storage tank.

[0019] Further improvement of the heat storage and release device is that a first control valve is arranged on a communication pipeline between the water tank and the pressurized water pump, a second control valve is arranged on a communication pipeline between the pressurized water pump and the high-pressure heat storage tank, a third control valve is arranged on a communication pipeline between the water outlet of the high-pressure heat storage tank and the water inlet of the flash evaporator, a fourth control valve is arranged on a communication pipeline between the steam inlet of the high-pressure heat storage tank and the steam outlet of the flash evaporator, and a fifth control valve is arranged on a communication pipeline between the flash evaporator and the heat release heat exchanger.

[0020] In the initial state, the first control valve, the second control valve, the third control valve, the fourth control valve and the fifth control valve are closed, low-temperature and low-pressure water is stored in the water tank, and high-temperature and high-pressure water vapor with a preset pressure is stored in the high-temperature heat storage tank.

[0021] When heat storage is performed, the first control valve and the second control valve are opened, and the third control valve, the fourth control valve and the fifth control valve are closed, so that the heat storage and heat release device performs heat storage work.

[0022] When heat release is performed, the third control valve, the fourth control valve and the fifth control valve are opened, and the first control valve and the second control valve are closed, so that the heat storage and heat release device performs heat release work.

[0023] Further improvement of the heat storage and heat release device is that the outlet water pressure of the booster water pump and the water vapor pressure in the high-pressure heat storage tank are greater than or equal to the saturation pressure of the outlet water temperature of the cold source heat exchange channel of the heat storage heat exchanger.

[0024] Further improvement of the heat storage and heat release device is that when the heat storage and heat release device performs heat storage work,

[0025] The water input into the high-pressure heat storage tank through the first water inlet and the water input into the high-pressure heat storage tank through the second water inlet satisfy the relationship,

[0026]

[0027] In the formula, m1 represents the mass of the water input through the first water inlet, m2 represents the mass of the water input through the second water inlet, m0 represents the mass of the original water vapor in the high-pressure heat storage tank, ρ1 represents the density of the water input through the first water inlet, ρ0 represents the density of the original water vapor in the high-pressure heat storage tank, h1 represents the enthalpy of the water input through the first water inlet, h2 represents the enthalpy of the water input through the second water inlet, and h0 represents the enthalpy of the original water vapor in the high-pressure heat storage tank.

[0028] Further improvement of the heat storage and heat release device is that when the heat storage and heat release device performs heat release work,

[0029] The water vapor input through the steam inlet and the heat storage water output through the water outlet of the high-pressure heat storage tank satisfy the relationship:

[0030]

[0031] In the formula, m l represents the mass of the water input through the water outlet of the high-pressure heat storage tank, m g represents the mass of the water vapor input through the steam inlet of the high-pressure heat storage tank, ρ l represents the density of the water input through the water outlet of the high-pressure heat storage tank, ρ g represents the density of the water vapor input through the steam inlet of the high-pressure heat storage tank.

[0032] The further improvement of the heat storage and release device is that the high-pressure heat storage tank outputs the heat storage water flowing into the water tank after heat release.

[0033] The second aspect of the present application provides a heat storage and release method using water as a medium, which is based on the heat storage and release device of the first aspect of the present application, and the heat storage and release method comprises:

[0034] If the first water inlet of the high-pressure heat storage tank inputs the water after heat absorption, the second water inlet inputs the water after pressure increase, so that the water vapor stored in the high-pressure heat storage tank is condensed to balance the change of water pressure in the high-pressure heat storage tank caused by the input of the water after heat absorption.

[0035] If the high-pressure heat storage tank outputs the heat storage water, the steam inlet inputs the water vapor to balance the change of water pressure in the high-pressure heat storage tank caused by the output of the heat storage water.

[0036] Compared with the prior art, the present application has the following beneficial effects:

[0037] The heat storage and release device provided by the present application uses water as a heat storage medium, can store excess heat when the external heat is abundant, and can release heat when the external heat is scarce, so as to realize full utilization of energy.

[0038] The present application utilizes the phase change of water to realize pressure stability.

[0039] In the present application, a water turbine is also provided, which can utilize the high-pressure water expansion after heat release to do work, so as to greatly improve the energy utilization rate of the device and further improve the heat storage efficiency of the device.

[0040] In the method, the water distribution ratio can be adjusted by adjusting the opening degree of the second control valve, so that the low-temperature high-pressure water can be condensed into sufficient high-temperature high-pressure steam in the high-pressure heat storage tank, and the pressure in the high-pressure heat storage tank is kept stable; the pressure drop of the high-pressure water in the flash evaporator can be adjusted by controlling the valve opening degrees of the fourth control valve and the fifth control valve, so that the amount of generated steam can be controlled; in the technical solution, the heat storage and release time and the working medium flow can be controlled to control the capacity, so that the energy can be fully utilized. BRIEF DESCRIPTION OF DRAWINGS

[0041] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following briefly introduces the drawings needed to be used in the embodiments or the prior art description; obviously, the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0042] Figure 1 is a structure schematic diagram of a heat storage and release device using water as medium provided by the embodiment of the present application;

[0043] In the figure, 1 is a water tank, 2 is a booster water pump, 3 is a heat storage and release heat exchanger, 4 is a high-pressure heat storage tank, 5 is a flash evaporator, 6 is a steam pump, 7 is a heat release heat exchanger, and 8 is a water turbine.

[0044] 9 is a first control valve, 10 is a second control valve, 11 is a third control valve, 12 is a fourth control valve, and 13 is a fifth control valve. DETAILED DESCRIPTION

[0045] In order to make the person skilled in the art better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should belong to the scope of protection of the present application.

[0046] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting, unless the context clearly indicates otherwise. It will be further understood that the use of relational terms such as first and second, and the like are used solely to distinguish one from another entity without necessarily implying a relationship or order between these entities. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an overly literal or overly formal sense unless expressly so defined herein.

[0047] The application will be further described in details below with reference to the accompanying drawings:

[0048] The application provides a water medium heat storage and release device, which comprises:

[0049] A water tank 1 is configured to store low-temperature and low-pressure water to be heated.

[0050] A booster water pump 2 is configured to input water output by the water tank 1 and boost the water, and output the boosted water in two parts.

[0051] A heat storage and exchange device 3 is configured to input a part of the boosted water in a cold source exchange channel of the heat storage and exchange device 3, and output water after heat absorption.

[0052] A high-pressure heat storage tank 4 is configured to store high-temperature and high-pressure water vapor with a preset pressure. The high-pressure heat storage tank 4 is provided with a first water inlet, a second water inlet, a water outlet and a vapor inlet. The first water inlet is configured to input the water after heat absorption, and the second water inlet is configured to input another part of the boosted water. The vapor inlet is configured to supplement water vapor.

[0053] When the water medium heat storage and release device stores heat, the high-pressure heat storage tank 4 inputs the boosted water to condense the water vapor stored in the high-pressure heat storage tank 4, so as to balance the change of water pressure in the high-pressure heat storage tank 4 caused by the input of the water after heat absorption. When the water medium heat storage and release device releases heat, the water outlet is configured to output heat storage water, and the vapor inlet is configured to input water vapor, so as to balance the change of water pressure in the high-pressure heat storage tank 4 caused by the output of the heat storage water.

[0054] For example, low-temperature and low-pressure correspond to high-temperature and high-pressure, which specifically refer to that the temperature and pressure of the water in the water tank are lower than the temperature and pressure of the water vapor in the high-pressure heat storage tank.

[0055] The technical scheme provided in the embodiment of the present application has the following beneficial effects. The water tank is arranged to store low-temperature and low-pressure water to be heated, and the high-pressure heat storage tank is arranged to store high-temperature and high-pressure water vapor with preset pressure. Water is used as a heat storage medium, and the phase change of water is used to stabilize the pressure. The water tank can store excess heat when the external heat is abundant, and release heat when the external heat is scarce, so that the energy can be fully utilized. Further, the water that has absorbed heat is introduced into the first water inlet, and the water that has not absorbed heat is introduced into the second water inlet at the same time. The water vapor condensation is used to stabilize the water pressure of the high-pressure heat storage tank. When the high-temperature water in the high-pressure heat storage tank flows out to release heat, the water vapor is introduced into the steam inlet to stabilize the water pressure of the high-pressure heat storage tank. The evaporation and condensation of water can be used to stabilize the water pressure of the heat storage tank, so that the heat storage effect of the system can be improved, and the safety is good.

[0056] Please refer to Figure 1 The heat storage and release device with water as a medium provided by the embodiment of the present application comprises a water tank 1, a booster water pump 2, a heat storage heat exchanger 3, a high-pressure heat storage tank 4, a flash evaporator 5, a steam pump 6, and a heat release heat exchanger 7.

[0057] The water tank 1 is used to store water medium to be heated. The water medium to be heated can be normal-temperature and normal-pressure water. The water can be filtered and purified rainwater, domestic wastewater, or industrial wastewater, so that the water resource can be recycled.

[0058] The water outlet of the water tank 1 is connected to the water inlet of the booster water pump 2 through a first control valve 9. The water outlet of the booster water pump 2 is divided into two paths. One path is connected to the first water inlet of the high-pressure heat storage tank 4 through the cold source heat exchange channel of the heat storage heat exchanger 3. The other path is connected to the second water inlet of the high-pressure heat storage tank 4 through a first communication pipeline. A second control valve 10 is arranged on the first communication pipeline.

[0059] The outlet of the high-pressure heat storage tank 4 is connected to the inlet of the flash evaporator 5 through a third control valve 11. The first outlet of the flash evaporator 5 is connected to the steam inlet of the high-pressure heat storage tank 4 through a fourth control valve 12 and the steam pump 6. The second outlet of the flash evaporator 5 is connected to the heat source heat exchange channel of the heat release heat exchanger 7 through a fifth control valve 13.

[0060] In the technical scheme provided by the embodiment of the present application, the water in the water tank 1 is input to the booster water pump 2 through the outlet of the water tank and the first control valve 9 to be pressurized. The pressurized water is input to the cold source heat exchange channel of the heat storage heat exchanger 3 to be heated, and the water that has absorbed heat is sent to the high-pressure heat storage tank 4. The other path is delivered to the high-pressure heat storage tank 4 through the second control valve 10 to condense water vapor, so as to realize the pressurization, heating, and storage of water. The above constitutes the heat storage process of the entire device.

[0061] In the technical scheme provided by the embodiment of the present application, the high-temperature and high-pressure water of the high-pressure heat storage tank 4 is delivered to the flash evaporator 5 through the water outlet and the third control valve 11, the water vapor of the flash evaporator 5 is delivered to the high-pressure heat storage tank 4 through the fourth control valve 12 and the steam pump 6, the water of the flash evaporator 5 is delivered to the heat source heat exchange channel of the heat-releasing heat exchanger 7 through the fifth control valve 13 to release heat, and the water after heat-releasing heat exchange can be returned to the water tank 1 or returned to the water tank 1 after work, so that the heat release of water and the pressure maintenance of the high-pressure heat storage tank 4 are realized.

[0062] In order to further improve the energy utilization rate and heat storage efficiency, the embodiment of the present application is further improved in that the heat-releasing heat exchanger 7 is further provided with a water turbine 8 for generating electricity by using the water after heat exchange of the heat-releasing heat exchanger 7; specifically, the outlet of the heat source heat exchange channel of the heat-releasing heat exchanger 7 is connected with the inlet of the water turbine 8, and the outlet of the water turbine 8 is connected with the water inlet of the water tank 1. In the improved technical scheme of the embodiment of the present application, the water after heat-releasing work is stored in a normal pressure state, which can reduce the number of high-pressure storage devices, greatly reduce the manufacturing cost of the equipment, and improve the application range of the device.

[0063] In the embodiment of the present application, in order to ensure that the pressure of the high-pressure heat storage tank 4 is maintained stably, the water entering the high-pressure heat storage tank 4 through the first water inlet and the water entering the high-pressure heat storage tank 4 through the second water inlet satisfy the following relationship:

[0064]

[0065] In the formula, m1 represents the mass of the water delivered through the first water inlet, m2 represents the mass of the water delivered through the second water inlet, m0 represents the mass of the original water vapor in the high-pressure heat storage tank, ρ1 represents the density of the water delivered through the first water inlet, ρ0 represents the density of the original water vapor in the high-pressure heat storage tank, h1 represents the enthalpy of the water delivered through the first water inlet, h2 represents the enthalpy of the water delivered through the second water inlet, and h0 represents the enthalpy of the original water vapor in the high-pressure heat storage tank.

[0066] In the embodiment of the present application, the relationship between the steam inlet and the water outlet is:

[0067]

[0068] In the formula, m l represents the mass of the water delivered through the water outlet of the high-pressure heat storage tank, m g represents the mass of the water vapor delivered through the steam inlet of the high-pressure heat storage tank, ρ l represents the density of the water delivered through the water outlet of the high-pressure heat storage tank, and ρ g represents the density of the water vapor delivered through the steam inlet of the high-pressure heat storage tank.

[0069] In this embodiment of the invention, considering practical issues, the heat source heat exchange channel of the thermal storage heat exchanger 3 can be connected to low-temperature waste heat from industrial production (waste gas and wastewater below 300℃), high-temperature gas from the compressor outlet of a compressed gas energy storage system, etc. In this embodiment of the invention, considering practical issues, the cold source heat exchange channel of the heat release heat exchanger 7 can be connected to production heat (working fluid preheating, drying, etc.), domestic heat (heating, bathing, etc.), and medium- and low-temperature gas from the turbine inlet of a compressed gas energy storage system, etc. In specific exemplary application scenarios, this invention can be coupled with a gas-liquid phase change carbon dioxide energy storage system; the thermal storage heat exchanger 3 and the heat release heat exchanger 7 can adopt the energy storage heat exchanger and energy release heat exchanger disclosed in Chinese invention patent authorization announcement numbers CN112985143B, CN112985144B, and CN112985145B.

[0070] This invention provides a method for heat storage and release using water as a medium. If heat-absorbing water is input into the first inlet of the high-pressure heat storage tank 4, pressurized water is input into the second inlet, causing the water vapor stored in the high-pressure heat storage tank 4 to condense, thereby balancing the water pressure change inside the high-pressure heat storage tank 4 caused by the input of heat-absorbing water. If the high-pressure heat storage tank 4 outputs stored hot water, water vapor is input into the steam inlet, thereby balancing the water pressure change inside the high-pressure heat storage tank 4 caused by the output of stored hot water.

[0071] For example, see Figure 1 As shown, the heat storage and release method using water as a medium specifically includes the following steps:

[0072] In the initial state, all five control valves are closed, water tank 1 contains a certain amount of normal temperature and pressure water, and high temperature and high pressure steam is contained in the high temperature storage tank.

[0073] When storing heat, the first control valve 9 and the second control valve 10 are opened, and the third control valve 11, the fourth control valve 12, and the fifth control valve 13 are closed, and the heat storage and release device performs heat storage work. The room temperature and pressure water stored in the water tank 1 is pressurized by the booster pump 2 (which can be provided by off-peak electricity) and then divided into two streams. One stream absorbs heat and heats up through the heat storage heat exchanger 3 (provided by external heat) and enters the high-pressure heat storage tank 4 for storage. The other stream enters from the top of the high-pressure heat storage tank 4 through the second control valve 10. The room temperature and high pressure water condenses and stores the high-temperature and high-pressure steam in the high-pressure heat storage tank 4. To be more specific, the room temperature and high pressure water from the other stream is sprayed from the top of the high-pressure heat storage tank 4, absorbing the heat of the high-temperature and high-pressure steam and heating it up. The high-temperature and high-pressure steam condenses into a high-temperature and high-pressure liquid, reducing the gas volume and stabilizing the pressure, thus completing the heat storage.

[0074] When discharging heat, the third control valve 11, the fourth control valve 12 and the fifth control valve 13 are opened, and the first control valve 9 and the second control valve 10 are closed, so that the heat storage and discharge device discharges heat; the high-temperature and high-pressure water stored in the high-pressure heat storage tank 4 enters the flash evaporator 5 to reduce the pressure and evaporate, the steam generated by the flash evaporation is pressurized by the steam pump 6 and then returns to the high-pressure heat storage tank 4 to maintain the pressure in the heat storage tank basically stable, the water after the flash evaporation enters the heat discharge heat exchanger 7 to discharge heat and cool to room temperature, and the high-pressure water after the cooling enters the water turbine 8 to expand to normal pressure and drive the generator to generate electricity (power peak), and the water after the work returns to the normal pressure water tank 1 for storage, and thus the heat release is completed.

[0075] For example, the heat storage is surplus heat of the outside world and / or off-peak power, and the heat discharge is insufficient heat of the outside world and / or power peak.

[0076] In the embodiment of the application, the high-pressure heat storage tank 4 is further provided with an electric heating device, when the heat storage part starts to work, if the temperature and pressure of the steam in the high-pressure heat storage tank 4 are relatively low, the off-peak electric heating device is used to heat the steam to improve the temperature and pressure of the steam, so that heat exchange or expansion does not occur when the high-temperature and high-pressure water enters, thereby ensuring the stability of the device work. When the heat storage is completed, if the temperature of the high-temperature and high-pressure water in the high-pressure heat storage tank 4 is relatively low, the off-peak electric heating device is used to heat the high-temperature and high-pressure water to improve the temperature of the high-temperature and high-pressure water, thereby stabilizing the heat discharge efficiency.

[0077] In the method of the embodiment of the application, the water diversion ratio can be adjusted by adjusting the opening degree of the second control valve 10, so as to ensure that the low-temperature and high-pressure water can condense sufficient high-temperature and high-pressure steam, and the pressure in the high-pressure heat storage tank 4 is stable; the amount of steam generated can be controlled by controlling the valve opening degree of the fourth control valve 12 and the fifth control valve 13, and adjusting the pressure drop of the high-pressure water in the flash evaporator 5; further, the pressure drop in the flash evaporator 5 should be controlled in a relatively small range, so as to ensure that the generated steam can maintain the pressure in the high-pressure heat storage tank 4 stable. Therefore, the capacity can be controlled by controlling the heat storage and discharge time and the working medium flow, so that the energy can be fully utilized.

[0078] In the embodiment of the application, the water pressure at the outlet of the booster water pump 2 and the pressure of the steam in the high-pressure heat storage tank 4 should be greater than or equal to the saturation pressure of the water temperature at the outlet of the heat storage heat exchanger 3, so that the water after heat exchange is in liquid state, and the stable work of the heat storage device is ensured.

[0079] The method provided by the embodiment of the application can realize that when the heat of the outside world is abundant, the excess heat is stored in the high-temperature heat storage tank, and when the heat of the outside world is insufficient, the heat release is completed through the heat discharge heat exchanger 7, so that the energy can be fully utilized, the heat storage device works flexibly and stably, has high heat storage efficiency, the pressure of the heat storage tank is stable in the process of storing and releasing the heat contained in the high-temperature and high-pressure water, does not affect the heat storage effect of the energy storage system, and ensures the safety of the energy storage system.

[0080] To sum up, the embodiment of the present application specifically provides a water medium heat storage and release device and method, the device uses water as a heat storage medium to flexibly realize heat storage and release, and realizes full utilization of energy; the pressure stability of the high-pressure heat storage tank can be flexibly controlled by using the state changes such as evaporation and condensation of water, so that the pressure of the heat storage tank is stable during the heat storage and release process, and the heat storage effect of the energy storage system is not affected, and the device has the advantages of high heat storage efficiency, flexible and stable work, high safety and the like. Specifically, the core advantages of the present application mainly include:

[0081] (1) The present application can realize heat storage when external heat is abundant, and release heat when external heat is lacking, and can control the capacity by controlling the heat storage and release time and the working fluid flow, so as to flexibly realize full utilization of energy, and effectively improve the heat storage efficiency of the device;

[0082] (2) The present application uses water as a heat storage medium, and uses the state changes such as condensation and evaporation of water to flexibly control the pressure stability of the high-pressure heat storage tank, and ensures the stability of the device; at the same time, water is non-toxic and non-flammable, which can effectively improve the safety of the device;

[0083] (3) The present application uses the high-pressure water expansion work after heat release to greatly improve the energy utilization rate of the device, and further improves the heat storage efficiency of the device;

[0084] (4) The present application has compact structure and simple equipment; at the same time, the water after heat release is stored in normal pressure state, which can reduce the number of high-pressure storage equipment, greatly reduce the manufacturing cost of the equipment, and improve the application range of the device;

[0085] (5) The water used in the present application can be filtered and purified rainwater, domestic wastewater or industrial wastewater, which effectively realizes the recycling of water resources.

[0086] Finally, it should be explained that: the above embodiments are only used to illustrate the technical solutions of the present application but not to limit it, although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that the specific embodiments of the present application can be modified or replaced by the same, without departing from the spirit and scope of the present application, any modification or equivalent replacement thereof should be covered in the protection scope of the claims of the present application.

Claims

1. A heat storage and release device using water as a medium, characterized in that, include: Water tank (1) is used to store low-temperature, low-pressure water to be heat exchanged; A booster pump (2) is used to input and pressurize the water output from the water tank (1), and output the pressurized water in two parts; The heat storage heat exchanger (3) has a cold source heat exchange channel for inputting a portion of the pressurized water and outputting water after heat absorption. A high-pressure heat storage tank (4) is used to store high-temperature and high-pressure steam with a preset pressure; the high-pressure heat storage tank (4) is provided with a first water inlet, a second water inlet, a water outlet and a steam inlet; the first water inlet is used to input the water after heat absorption, and the second water inlet is used to input another part of the pressurized water; When the water-based heat storage and release device stores heat, the pressurized water input into the high-pressure heat storage tank (4) is used to condense the water vapor stored in the high-pressure heat storage tank (4) to balance the water pressure change in the high-pressure heat storage tank (4) caused by the input of water after heat absorption; when the water-based heat storage and release device releases heat, the outlet is used to output the stored hot water, and the steam inlet is used to input water vapor to balance the water pressure change in the high-pressure heat storage tank (4) caused by the output of the stored hot water.

2. The heat storage and release device using water as a medium according to claim 1, characterized in that, Also includes: Flash evaporator (5), the inlet of the flash evaporator (5) is connected to the outlet of the high-pressure heat storage tank (4), and the steam outlet of the flash evaporator (5) is connected to the steam inlet of the high-pressure heat storage tank (4) via a steam pump (6). The heat exchanger (7) has its heat source heat exchange channel inlet connected to the outlet of the flash evaporator (5) and its heat source heat exchange channel outlet connected to the water tank (1).

3. The heat storage and release device using water as a medium according to claim 2, characterized in that, Also includes: A water turbine (8) is installed between the heat exchanger (7) and the water tank (1) to generate electricity by using the water output from the heat source heat exchange channel of the heat exchanger (7) and to input the water after generating electricity into the water tank (1).

4. The heat storage and release device using water as a medium according to claim 1, characterized in that, The high-pressure heat storage tank (4) is also equipped with an electric heating device for heating the high-pressure heat storage tank (4).

5. A heat storage and release device using water as a medium according to claim 2, characterized in that, A first control valve (9) is provided on the connecting pipe between the water tank (1) and the booster pump (2), a second control valve (10) is provided on the connecting pipe between the booster pump (2) and the high-pressure heat storage tank (4), a third control valve (11) is provided on the connecting pipe between the outlet of the high-pressure heat storage tank (4) and the inlet of the flash evaporator (5), a fourth control valve (12) is provided on the connecting pipe between the steam inlet of the high-pressure heat storage tank (4) and the steam outlet of the flash evaporator (5), and a fifth control valve (13) is provided on the connecting pipe between the flash evaporator (5) and the heat exchanger (7). In the initial state, the first control valve (9), the second control valve (10), the third control valve (11), the fourth control valve (12), and the fifth control valve (13) are all closed. The water tank (1) stores low-temperature and low-pressure water, and the high-temperature heat storage tank stores high-temperature and high-pressure steam at a preset pressure. When storing heat, the first control valve (9) and the second control valve (10) are opened, and the third control valve (11), the fourth control valve (12), and the fifth control valve (13) are closed, and the heat storage and heat release device performs heat storage work; When releasing heat, the third control valve (11), the fourth control valve (12), and the fifth control valve (13) are opened, and the first control valve (9) and the second control valve (10) are closed, and the heat storage and heat release device performs heat release work.

6. The heat storage and heat release device according to claim 1, characterized in that, The outlet water pressure of the booster pump (2) and the water vapor pressure inside the high-pressure heat storage tank (4) are both greater than or equal to the saturation pressure at the outlet water temperature of the cold source heat exchange channel of the heat storage heat exchanger (3).

7. The heat storage and heat release device according to claim 1, characterized in that, When the heat storage and heat release device performs heat storage operation... The water entering the high-pressure thermal storage tank (4) through the first inlet and the water entering the high-pressure thermal storage tank (4) through the second inlet satisfy a certain relationship. In the formula, m1 represents the mass of water supplied through the first inlet, m2 represents the mass of water supplied through the second inlet, m0 represents the mass of the original water vapor in the high-pressure heat storage tank, ρ1 represents the density of water supplied through the first inlet, ρ0 represents the density of the original water vapor in the high-pressure heat storage tank, h1 represents the enthalpy of water supplied through the first inlet, h2 represents the enthalpy of water supplied through the second inlet, and h0 represents the enthalpy of the original water vapor in the high-pressure heat storage tank.

8. The heat storage and heat release device according to claim 1, characterized in that, When the heat storage and heat release device is performing heat release operation... The steam input through the steam inlet and the stored hot water output through the outlet of the high-pressure thermal storage tank (4) satisfy the following relationship: In the formula, m l The mass of water supplied from the outlet of the high-pressure thermal storage tank, m g ρ represents the mass of the steam supplied to the steam inlet of the high-pressure thermal storage tank. l ρ represents the density of the water supplied at the outlet of the high-pressure thermal storage tank. g This indicates the density of the steam supplied to the steam inlet of the high-pressure thermal storage tank.

9. The heat storage and heat release device according to claim 1, characterized in that, The hot water output from the high-pressure thermal storage tank flows into the water tank after releasing heat.

10. A method for heat storage and release using water as a medium, characterized in that, Based on the heat storage and heat release device as described in any one of claims 1 to 9, the heat storage and heat release method includes: If the first inlet of the high-pressure heat storage tank (4) is filled with water that has absorbed heat, then the second inlet is filled with pressurized water, so that the water vapor stored in the high-pressure heat storage tank (4) will condense, thereby balancing the water pressure change in the high-pressure heat storage tank (4) caused by the input of water that has absorbed heat. If the high-pressure heat storage tank (4) outputs hot water, steam is introduced into the steam inlet to balance the water pressure change in the high-pressure heat storage tank (4) caused by the output of hot water.

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