Cross-seasonal heat storage system coupled with absorption heat pump and high-temperature heat pump

Abstract

The invention relates to a cross-seasonal heat storage system coupled with an absorption heat pump and a high-temperature heat pump, and belongs to the technical field of energy development and utilization. The heat storage system comprises a heat storage unit, and the heat storage unit comprises a first pump, a heat storage pool, a second coupling absorption heat pump unit or a second heat exchanger which are sequentially closed and communicated in a loop mode through pipelines; the heat release unit comprises a second pump, a first three-way valve, a first heat exchanger, a second three-way valve, a first coupling absorption heat pump unit or a high-temperature heat pump, a third three-way valve, a heat supply station, a third pump and a fourth three-way valve which are sequentially communicated through pipelines; according to the system, high-temperature steam or waste heat resources in the non-heating season are converted into heat energy through the heat pump unit and stored in the reservoir, high-temperature steam and industrial waste heat of a power plant are fully utilized, energy waste is reduced, the overall energy utilization rate is increased, and in addition, the system is beneficial to balancing energy supply and demand, reducing peak load in the heating season and reducing energy system pressure.

Description

Technical Field

[0001] The invention discloses a cross-season heat storage system for coupling an absorption heat pump and a high-temperature heat pump, belonging to the technical field of energy development and utilization. Background Art

[0002] With the rapid development of renewable energy and the increasing volatility of energy demand, how to effectively utilize energy and improve energy utilization has become one of the core issues in the global energy field. Against the background of seasonal fluctuations in heating demand, energy consumption is relatively high during the heating season, while in the non-heating season, high-temperature heat sources such as high-temperature steam from power plants and industrial waste heat are often not fully utilized, resulting in energy waste. Therefore, the research and application of cross-seasonal heat storage systems is particularly important.

[0003] Most existing inter-seasonal heat storage systems use solar energy as the main heat source, using solar energy to heat the heat storage medium in the non-heating season and releasing the stored heat for heating in the heating season. However, such systems are highly dependent on solar energy resources and are significantly affected by weather and seasonal fluctuations, making it difficult to achieve stable operation in areas with insufficient solar energy resources. In contrast, power plant waste heat, as a stable and continuous heat source, is not affected by weather and seasons, has strong dispatchability and reliability, and therefore has important application potential in the field of inter-seasonal heat storage. Summary of the invention

[0004] In order to solve the problems existing in the prior art, such as single heat source form and poor heat source stability, we proposed a cross-seasonal heat storage system that couples absorption heat pumps and high-temperature heat pumps.

[0005] The present invention provides a cross-seasonal heat storage system that couples an absorption heat pump and a high-temperature heat pump, such as Figures 1-2 As shown, the heat storage system includes:

[0006] A heat storage unit, the heat storage unit comprising a first pump 1, a heat storage tank 2, a second coupled absorption heat pump unit 12 or a second heat exchanger 14, which are sequentially connected in a closed loop through pipelines;

[0007] The heat release unit includes a second pump 3, a first three-way valve 4, a first heat exchanger 5, a second three-way valve 6, a first coupled absorption heat pump unit 7 or a high-temperature heat pump 13, a third three-way valve 8, a heating station 9, a third pump 10 and a fourth three-way valve 11 which are sequentially connected through pipelines, and the lower right outlet of the heat storage tank 2 is connected to the left inlet of the second pump 3.

[0008] Furthermore, when the second coupled absorption heat pump unit 12 is located on the lower left side of the heat storage tank 2 , the first coupled absorption heat pump unit 7 is located on the right side of the second three-way valve 6 .

[0009] Further, when the second heat exchanger 14 is located on the lower left side of the heat storage tank 2 , the high-temperature heat pump 13 is located on the right side of the first and second three-way valves 6 .

[0010] Furthermore, a temperature sensor is provided at the first three-way valve 4. According to the inflow water temperature, when it is higher than 60°C, the outlet r is opened and the outlet q is closed; when it is lower than 60°C, the outlet q is opened and the outlet r is closed.

[0011] Furthermore, the second three-way valve 6 is provided with a linkage device of the first three-way valve 4. According to the temperature of water flowing into the first three-way valve 4, when it is higher than 60°C, the inlet t is opened and the inlet s is closed; when it is lower than 60°C, the inlet s is opened and the inlet t is closed.

[0012] Furthermore, the third three-way valve 8 is provided with a linkage device of the first three-way valve 4. According to the water temperature flowing into the first three-way valve 4, when it is higher than 60°C, the inlet x and the inlet w are opened; when it is lower than 60°C, the inlet w is opened and the inlet x is closed.

[0013] Furthermore, the fourth three-way valve 11 is provided with a linkage device of the first three-way valve 4. According to the water temperature flowing into the first three-way valve 4, when it is higher than 60°C, the outlet u and the outlet v are opened; when it is lower than 60°C, the outlet v is opened and the outlet u is closed.

[0014] Furthermore, the fourth three-way valve 11 is provided with a linkage device of the first three-way valve 4. When the temperature of water flowing into the first three-way valve 4 is higher than 60°C, the valve opening is adjusted according to the water temperature, and the outlet flow rates of the outlet v and the outlet u are adjusted accordingly.

[0015] The beneficial effects of the present invention are:

[0016] 1. The present invention converts high-temperature steam or waste heat resources in the non-heating season into thermal energy through a heat pump unit and stores it in a water reservoir. The system can make full use of high-temperature steam and industrial waste heat from power plants, reduce energy waste, and improve overall energy utilization.

[0017] 2. The system of the present invention can store surplus thermal energy in the non-heating season and release it in the heating season, which helps to balance energy supply and demand, reduce peak load in the heating season, reduce pressure on the energy system, and improve the safety and stability of the system. Since the energy cost in the non-heating season is lower, the system can store thermal energy at a low cost for use in the heating season, reducing the energy cost required for heating in winter, thereby saving operating costs.

[0018] 3. The present invention reduces the dependence on traditional fossil fuels, especially during the heating season, and the system reduces carbon emissions, which has a positive effect on environmental protection.

[0019] 4. The system of the present invention can be combined with various types of high-temperature heat sources, such as waste heat from power plants, heat from swimming pools, etc., which increases the flexibility of application and can be promoted and used in different types of industrial or energy scenarios.

[0020] 5. The absorption heat pump unit of the present invention can efficiently convert low-grade heat sources into high-grade thermal energy and store it in a water reservoir, ensuring that the thermal energy can be stably stored and effectively released when needed. Through the coordination of various equipment, the system can operate stably under different working conditions and has good reliability and adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the overall structure of the present invention, which also serves as an abstract drawing.

[0022] Figure 2 It is a schematic diagram of the overall structure of the second embodiment of the present invention.

[0023] Description of reference numerals:

[0024] 1. First pump, 2. Heat storage tank, 3. Second pump, 4. First three-way valve, 5. First heat exchanger, 6. Second three-way valve, 7. First coupled absorption heat pump unit, 8. Third three-way valve, 9. Heating station, 10. Third pump, 11. Fourth three-way valve, 12. Second coupled absorption heat pump unit, 13. High-temperature heat pump, 14. Second heat exchanger. DETAILED DESCRIPTION

[0025] A specific implementation case of the present invention is given below in conjunction with the accompanying drawings to introduce the structure and implementation method of the present invention in detail. It should be noted that the scope of application of the present invention is not limited to the following embodiments, and all similar structures based on the present invention are within the scope of application of the present invention.

[0026] The present invention provides a cross-seasonal heat storage system for coupling an absorption heat pump and a high-temperature heat pump, the heat storage system comprising:

[0027] A heat storage unit, the heat storage unit comprising a first pump 1, a heat storage tank 2, a second coupled absorption heat pump unit 12 or a second heat exchanger 14, which are sequentially connected in a closed loop through pipelines;

[0028] The heat release unit includes a second pump 3, a first three-way valve 4, a first heat exchanger 5, a second three-way valve 6, a first coupled absorption heat pump unit 7 or a high-temperature heat pump 13, a third three-way valve 8, a heating station 9, a third pump 10 and a fourth three-way valve 11 which are sequentially connected through pipelines.

[0029] Embodiment 1:

[0030] like Figure 1As shown, when the lower left side of the heat storage tank 2 is the second coupled absorption heat pump unit 12 , the right side of the second three-way valve 6 is the first coupled absorption heat pump unit 7 .

[0031] The right side outlet of the first pump 1 is connected to the upper left side inlet of the heat storage tank 2, the lower left side outlet of the heat storage tank 2 is connected to the right side inlet a of the second coupled absorption heat pump unit 12, the left side inlet d of the second coupled absorption heat pump unit 12 is connected to the left side inlet of the first pump 1, the right side inlet b of the second coupled absorption heat pump unit 12 is connected to the high-temperature steam of the power plant, the right side inlet c of the second coupled absorption heat pump unit 12 is connected to the summer circulating water return of the thermal power plant, the left side outlet e of the second coupled absorption heat pump unit 12 is connected to the steam outlet, the left side outlet f of the second coupled absorption heat pump unit 12 is connected to the summer circulating water supply of the thermal power plant, the lower right side outlet of the heat storage tank 2 is connected to the left side inlet of the second pump 3, the right side outlet of the second pump 3 is connected to the left side inlet of the first three-way valve 4, the outlet q of the first three-way valve 4 is connected to the inlet s of the second three-way valve 6, the outlet r of the first three-way valve 4 is connected to the left side inlet g of the first heat exchanger 5, and the right side of the first heat exchanger 5 The outlet i is connected to the inlet t of the second three-way valve 6, the outlet of the second three-way valve 6 is connected to the left inlet k of the first coupled absorption heat pump unit 7, the right outlet n of the first coupled absorption heat pump unit 7 is connected to the upper right inlet of the heat storage tank 2, the left outlet of the heating station 9 is connected to the right inlet of the third pump 10, the left outlet of the third pump 10 is connected to the inlet of the fourth three-way valve 11, the outlet u of the fourth three-way valve 11 is connected to the left inlet h of the first heat exchanger 5, the right outlet j of the first heat exchanger 5 is connected to the inlet x of the third three-way valve 8, the outlet v of the fourth three-way valve 11 is connected to the left inlet m of the first coupled absorption heat pump unit 7, the right outlet p of the first coupled absorption heat pump unit 7 is connected to the inlet w of the third three-way valve 8, the outlet of the third three-way valve 8 is connected to the right inlet of the heating station 9, the left inlet l of the first coupled absorption heat pump unit 7 is connected to the high-temperature steam of the power plant, and the right outlet o of the first coupled absorption heat pump unit 7 is connected to the steam outlet.

[0032] The working principle and working process of the first embodiment of the present invention are as follows:

[0033] Heat storage process: In the non-heating season, water at normal temperature and pressure flows from the outlet of the heat storage tank 2 into the inlet a of the second coupled absorption heat pump unit 12, and at the same time, high-temperature steam flows in from the inlet b of the second coupled absorption heat pump unit 12. The circulating water return water of the thermal power plant in summer flows in from the inlet c of the second coupled absorption heat pump unit 12, and the circulating water temperature is increased by high-temperature steam, and flows out from the outlet of the second coupled absorption heat pump unit 12. At the same time, the high-temperature and normal-pressure water is heated to prepare high-temperature water and return to the heat storage tank 2. Since there is temperature stratification in the heat storage tank 2, the upper layer is hot water flowing into the heat storage tank 2, and the lower layer is normal-temperature water flowing out of the heat storage tank 2, until the water temperature of the upper layer of the heat storage tank 2 reaches the heating requirement.

[0034] Heat release process: In the heating season, the temperature of the hot water stored in the heat storage tank 2 decreases after the non-heating season, but it can still meet the heating requirements. When the outlet water temperature of the upper layer of the heat storage tank 2 is higher than 60°C, the outlet r of the first three-way valve 4 is opened, the outlet q is closed, the inlet t of the second three-way valve 6 is opened, the inlet s is closed, the outlet v and outlet u of the fourth three-way valve 11 are both opened, and the outlet water temperature of the upper layer of the heat storage tank 2 is adjusted. The valve opening is adjusted according to the outlet flow of outlet v and outlet u. The high-temperature water flows from the outlet of the heat storage tank 2 into the second pump 3, and then flows into the outlet r of the first three-way valve 4 and then into the first heat exchanger 5. After heat exchange and cooling, it flows into the first coupled absorption heat pump unit 7, and returns to the heat storage tank 2 after releasing heat. At the same time, the heating return water of the heating station 9 flows through the third pump 10 and enters the fourth three-way valve 11, and is divided into two streams and enters the outlet u and the outlet v respectively. The first stream enters the first heat exchanger 5 to absorb heat, and the second stream enters the first coupled absorption heat pump unit 7 to absorb heat. After absorbing heat, the two fluids enter the third three-way valve 8 from the inlet x and the inlet w respectively to mix. The mixed water temperature is not higher than 90°C, and returns to the heating station 9 as heating water supply to heat users.

[0035] When the outlet water temperature of the upper layer of the heat storage tank 2 is lower than 60°C, the outlet q of the first three-way valve 4 is opened, and the outlet r is closed, the inlet s of the second three-way valve 6 is opened, and the inlet t is closed, and the outlet v of the fourth three-way valve 11 is opened, and the outlet u is closed. The high-temperature water flows from the outlet of the heat storage tank 2 into the second pump 3, and then into the outlet q of the first three-way valve 4, and then into the inlet s of the second three-way valve 6, and then into the first coupled absorption heat pump unit 7, and returns to the heat storage tank 2 after releasing heat. At the same time, the heating return water of the heating station 9 flows through the third pump 10 into the fourth three-way valve 11, and then passes through the outlet v and enters the first coupled absorption heat pump unit 7 to absorb heat. The water temperature that absorbs heat is not higher than 90°C, and returns to the heating station 9 as heating water supply to heat users.

[0036] Embodiment 2:

[0037] like Figure 2 As shown, when the lower left side of the heat storage tank 2 is the second heat exchanger 14 , the right side of the first and second three-way valves 6 is the high-temperature heat pump 13 .

[0038] The working principle and working process of the second embodiment of the present invention are as follows:

[0039] Heat storage process: In the non-heating season, water at normal temperature and pressure flows from the outlet of the heat storage tank 2 into the inlet ae of the second heat exchanger 14. At the same time, the circulating water that absorbs the heat of the swimming pool stack flows into the inlet ad of the second heat exchanger 14. After heat exchange, the circulating water flows out from the outlet af of the second heat exchanger 14 and returns to the swimming pool stack. At the same time, the high-temperature and normal-pressure water is heated to produce high-temperature water and return to the heat storage tank 2. Since there is temperature stratification in the heat storage tank 2, the upper layer is hot water flowing into the heat storage tank 2, and the lower layer is normal-temperature water flowing out of the heat storage tank 2, until the water temperature of the upper layer of the heat storage tank 2 reaches the heating requirement.

[0040] Heat release process: In the heating season, the temperature of the hot water stored in the heat storage tank 2 decreases after the non-heating season, but it can still meet the heating requirements. When the outlet water temperature of the upper layer of the heat storage tank 2 is higher than 60°C, the outlet r of the first three-way valve 4 is opened, the outlet q is closed, the inlet t of the second three-way valve 6 is opened, the inlet s is closed, the outlet v and outlet u of the fourth three-way valve 11 are both opened, and the outlet water temperature of the upper layer of the heat storage tank 2 is adjusted. The valve opening is adjusted according to the outlet flow of outlet v and outlet u. The high-temperature water flows from the outlet of the heat storage tank 2 into the second pump 3, then into the outlet r of the first three-way valve 4, and then into the first heat exchanger 5. After heat exchange and cooling, it flows into the inlet y of the high-temperature heat pump 13, and returns to the heat storage tank 2 after releasing heat. At the same time, the heating return water of the heating station 9 flows through the third pump 10 and enters the fourth three-way valve 11, and is divided into two streams and enters the outlet u and the outlet v respectively. The first stream enters the first heat exchanger 5 to absorb heat, and the second stream enters the high-temperature heat pump 13 to absorb heat. After absorbing heat, the two fluids enter the third three-way valve 8 from the inlet x and the inlet w respectively to mix. The mixed water temperature is not higher than 90°C, and returns to the heating station 9 as heating water supply to heat users.

[0041] When the outlet water temperature of the upper layer of the heat storage tank 2 is lower than 60°C, the outlet q of the first three-way valve 4 is opened, and the outlet r is closed, the inlet s of the second three-way valve 6 is opened, and the inlet t is closed, the outlet v of the fourth three-way valve 11 is opened, and the outlet u is closed. The high-temperature water flows from the outlet of the heat storage tank 2 into the second pump 3, and then into the outlet q of the first three-way valve 4, and then into the inlet s of the second three-way valve 6, and into the high-temperature heat pump 13, and returns to the heat storage tank 2 after releasing heat. At the same time, the heating return water of the heating station 9 flows through the third pump 10 into the fourth three-way valve 11, and then passes through the outlet v and enters the high-temperature heat pump 13 to absorb heat. The water temperature that absorbs heat is not higher than 90°C, and returns to the heating station 9 as heating water supply to heat users.

Claims

1. A cross-seasonal heat storage system coupling an absorption heat pump and a high-temperature heat pump, characterized in that: The thermal storage system includes: A heat storage unit, the heat storage unit comprising a first pump (1), a heat storage tank (2), a second coupled absorption heat pump unit (12) or a second heat exchanger (14) which are sequentially connected in a closed loop manner through pipelines; A heat release unit, the heat release unit comprising a second pump (3), a first three-way valve (4), a first heat exchanger (5), a second three-way valve (6), a first coupled absorption heat pump unit (7) or a high-temperature heat pump (13), a third three-way valve (8), a heating station (9), a third pump (10) and a fourth three-way valve (11) which are sequentially connected through pipelines, and the lower right outlet of the heat storage tank (2) is connected to the left inlet of the second pump (3).

2. The cross-seasonal heat storage system of coupling absorption heat pump and high-temperature heat pump according to claim 1, characterized in that: When the lower left side of the heat storage tank (2) is the second coupled absorption heat pump unit (12), the right side of the second three-way valve (6) is the first coupled absorption heat pump unit (7).

3. The cross-seasonal heat storage system of coupling absorption heat pump and high-temperature heat pump according to claim 1, characterized in that: When the lower left side of the heat storage tank (2) is the second heat exchanger (14), the right side of the first and second three-way valves (6) is the high-temperature heat pump (13).

4. The cross-seasonal heat storage system of coupling absorption heat pump and high-temperature heat pump according to claim 1, characterized in that: The first three-way valve (4) is provided with a temperature sensor. When the inflow water temperature is higher than 60°C, the outlet r is opened and the outlet q is closed; when the inflow water temperature is lower than 60°C, the outlet q is opened and the outlet r is closed.

5. The cross-seasonal heat storage system of coupling absorption heat pump and high-temperature heat pump according to claim 1, characterized in that: The second three-way valve (6) is provided with a linkage device of the first three-way valve (4). When the temperature of water flowing into the first three-way valve (4) is higher than 60°C, the inlet t is opened and the inlet s is closed; when the temperature is lower than 60°C, the inlet s is opened and the inlet t is closed.

6. The cross-seasonal heat storage system of coupling absorption heat pump and high-temperature heat pump according to claim 1, characterized in that: The third three-way valve (8) is provided with a linkage device of the first three-way valve (4). When the temperature of water flowing into the first three-way valve (4) is higher than 60°C, the inlet x and the inlet w are opened; when the temperature is lower than 60°C, the inlet w is opened and the inlet x is closed.

7. The cross-seasonal heat storage system of coupling absorption heat pump and high-temperature heat pump according to claim 1, characterized in that: The fourth three-way valve (11) is provided with a linkage device of the first three-way valve (4), and when the temperature of the water flowing into the first three-way valve (4) is higher than 60°C, the outlet u and the outlet v are opened; when the temperature is lower than 60°C, the outlet v is opened and the outlet u is closed.

8. The cross-seasonal heat storage system of coupling absorption heat pump and high-temperature heat pump according to claim 1, characterized in that: The fourth three-way valve (11) is provided with a linkage device of the first three-way valve (4). When the temperature of water flowing into the first three-way valve (4) is higher than 60° C., the valve opening is adjusted according to the water temperature, and the outlet flow rates of the outlet v and the outlet u are adjusted accordingly.

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