Cold, warm and hot water triple-generation system of two-stage compression ground source heat pump
By using a two-stage compression ground source heat pump system, which combines low-pressure and high-pressure compressors, intermediate heat exchangers, and solar collectors, the problems of single function and low efficiency of existing ground source heat pump systems are solved. This achieves efficient integration of cooling, heating, and hot water supply, and enhances the system's adaptability to extreme weather conditions.
Patent Information
- Application Number
- CN202423025970.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-09
- Publication Date
- 2025-10-31
- Estimated Expiration
- 2034-12-09
AI Technical Summary
Existing ground source heat pump systems have limited functionality and low efficiency. They may experience insufficient heating or low efficiency, especially under extreme weather conditions, and require additional power support, leading to increased energy consumption.
The system employs a two-stage compression ground source heat pump system, including low-pressure and high-pressure compressors, intermediate heat exchangers, buried heat exchangers, multiple heat exchangers, valve assemblies, and solar collector assemblies. By increasing the compression ratio and utilizing soil energy storage, it achieves multi-functional integration of cooling, heating, and hot water supply.
It improves system efficiency, enhances adaptability to extreme weather conditions, reduces dependence on additional power sources, and achieves efficient integration of cooling, heating, and hot water supply.
Smart Images
Figure CN223499817U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the fields of refrigeration, air conditioning and heating technology, and more specifically, to a three-in-one system for cooling, heating and hot water using a two-stage compression ground source heat pump. Background Technology
[0002] Currently, ground source heat pumps are gaining increasing recognition as a highly efficient and environmentally friendly heating and cooling technology. In winter, ground source heat pumps utilize the stable temperature beneath the ground to provide heating for buildings, while in summer they extract heat from the building to achieve cooling. However, existing ground source heat pump systems often have functional limitations, leading users to install multiple systems, increasing system complexity and economic burden.
[0003] Existing single-stage ground source heat pump systems have relatively fixed efficiency in cooling and heating, making it difficult to adjust according to specific needs, especially in hot water supply, which often requires an additional water heater. This design may lead to insufficient heating or low efficiency under extreme weather conditions. Furthermore, traditional systems generally require additional power during operation, resulting in increased energy consumption. Utility Model Content
[0004] The problem solved by this utility model is that existing ground source heat pump systems have limited functionality and low efficiency.
[0005] To address the aforementioned problems, this utility model provides a two-stage compression ground source heat pump system for cooling, heating, and hot water, comprising: a compressor, an intermediate heat exchanger, a buried heat exchanger, multiple other heat exchangers, a valve assembly, and a solar collector assembly; the compressor includes a low-pressure compressor and a high-pressure compressor, with the outlet of the low-pressure compressor connected to the inlet of the high-pressure compressor; the intermediate heat exchanger includes a first intermediate heat exchanger and a second intermediate heat exchanger; the other heat exchangers include an outdoor heat exchanger and an indoor heat exchanger; the first intermediate heat exchanger is connected to the outlet of the low-pressure compressor, the inlet of the outdoor heat exchanger, and the inlet of the high-pressure compressor. The external heat exchanger is connected to the second intermediate heat exchanger; the second intermediate heat exchanger is connected to the indoor heat exchanger; the valve assembly includes a three-way valve and a four-way valve; the first port of the three-way valve is connected to the outlet of the high-pressure compressor, the second port of the three-way valve is connected to the first port of the four-way valve, and the third port of the three-way valve is connected to the solar collector assembly; the second port of the four-way valve is connected to the second intermediate heat exchanger, the third port of the four-way valve is connected to the inlet of the low-pressure compressor, and the fourth port of the four-way valve is connected to the outdoor heat exchanger; the outdoor heat exchanger is connected to the buried heat exchanger, and the buried heat exchanger is connected to the solar collector assembly.
[0006] Compared to existing technologies, the technical effects achieved by this solution are as follows: the exhaust gas of the low-pressure compressor is used as the intake gas of the high-pressure compressor, increasing the compression ratio and improving system efficiency; the outdoor heat exchanger condenses or evaporates the refrigerant; the indoor heat exchanger releases the cooling capacity during cooling and the heat during heating into the room; the buried heat exchanger releases excess energy into the soil; and the solar thermal collector is used to supply domestic hot water. This system can achieve four functions: cooling, heating, cooling and hot water production, and heating and hot water production.
[0007] Furthermore, the buried heat exchanger includes: a first buried heat exchanger, which is connected to an outdoor heat exchanger and is used to release heat to the soil when the system is cooling, or to release cold energy to the soil when the system is heating; and a second buried heat exchanger, which is connected to a solar collector assembly and is used for countercurrent heat exchange with the first buried heat exchanger.
[0008] Compared with existing technologies, the technical effects achieved by this technical solution are as follows: The first buried heat exchanger remains in normal operation to support the daily cooling and heating work of the system. However, due to the long-term operation of the system, the soil and the first buried heat exchanger continuously exchange heat, which will cause the soil temperature to drop, reduce the refrigerant evaporation temperature, and reduce the system efficiency. At this time, a second buried heat exchanger is needed to heat the soil, increase the soil temperature, and ensure the refrigerant evaporation temperature and system efficiency.
[0009] Furthermore, the solar thermal collector assembly includes: a hot water heat exchanger, a hot water tank, and a solar collector. The hot water heat exchanger is connected to the third port of a three-way valve; the hot water tank and the hot water heat exchanger form a loop connection; the solar collector and the hot water tank form a loop connection; and a second buried heat exchanger is connected in parallel to the loop formed by the solar collector and the hot water tank.
[0010] Compared with existing technologies, the technical effects achieved by this technical solution are as follows: the hot water tank is used to store domestic hot water, the solar collector is used to absorb solar energy to heat domestic water, and the hot water heat exchanger is used to heat domestic water using the heat generated during the system's cooling or heating process.
[0011] Furthermore, the valve assembly also includes: a first expansion valve and a first check valve. The first expansion valve and the first check valve are connected in series to indirectly form a flow branch; the flow branch is connected in parallel to the connecting pipe between the outdoor heat exchanger and the first intermediate heat exchanger, and / or, in parallel to the connecting pipe between the second intermediate heat exchanger and the first intermediate heat exchanger; wherein, the first check valve is located close to the first intermediate heat exchanger to restrict the unidirectional flow of the cooling medium to the first intermediate heat exchanger.
[0012] Compared with existing technologies, the technical effects achieved by this technical solution are as follows: the first one-way valve prevents refrigerant backflow, the first expansion valve realizes the throttling, cooling and depressurization of the refrigerant, and recovers part of the condensation heat.
[0013] Furthermore, the valve assembly also includes a second expansion valve. The second expansion valve is located between the second intermediate heat exchanger and the indoor heat exchanger.
[0014] Compared with existing technologies, the technical effect achieved by this technical solution is that the second expansion valve performs a second throttling and pressure reduction on the refrigerant.
[0015] Furthermore, the valve assembly also includes a second check valve. The second check valve is located between the hot water heat exchanger and the four-way valve.
[0016] Compared with existing technologies, the technical effect achieved by this technical solution is that the second one-way valve prevents refrigerant from flowing back into the hot water heat exchanger when the system is both cooling and producing hot water or heating and producing hot water.
[0017] Furthermore, the valve assembly also includes a solenoid valve. The solenoid valve is located on the parallel branch of the second underground heat exchanger, specifically near the outlet of the hot water tank.
[0018] Compared with existing technologies, the technical effect achieved by this technical solution is as follows: Under normal circumstances, the solenoid valve remains closed. When the hot water tank reaches the set temperature and the weather is sunny, the solenoid valve opens and sends hot water into the second underground heat exchanger to achieve countercurrent heat exchange with the first underground heat exchanger.
[0019] Furthermore, the dual-stage compression ground source heat pump cooling, heating, and hot water tri-generation system provided by this utility model also includes: a first water pump. The first water pump is located between the first buried heat exchanger and the outdoor heat exchanger, specifically near the outlet of the outdoor heat exchanger.
[0020] Compared with existing technologies, the technical effect achieved by this technical solution is as follows: the first water pump is used to pump the excess heat or cold energy of the refrigerant after condensation and heat release or evaporation and heat absorption into the first buried heat exchanger and release it into the soil.
[0021] Furthermore, the dual-stage compression ground source heat pump tri-generation system for cooling, heating, and hot water provided by this utility model also includes a second water pump. The second water pump is located between the hot water heat exchanger and the hot water tank, specifically near the inlet of the hot water tank.
[0022] Compared with the existing technology, the technical effect achieved by this technical solution is: the second water pump is used to pump the heat from the hot water heat exchanger into the hot water tank.
[0023] Furthermore, the dual-stage compression ground source heat pump cooling, heating, and hot water tri-generation system provided by this utility model also includes a third water pump. The third water pump is located between the solar collector and the hot water tank, specifically near the outlet of the hot water tank.
[0024] Compared with existing technologies, the technical effect achieved by this technical solution is as follows: when producing hot water, the solenoid valve is closed and the third water pump is started, so that the domestic water in the water tank is heated by the solar collector and then sent back to the hot water tank. Attached Figure Description
[0025] Figure 1 A schematic diagram of the structure of a dual-stage compression ground source heat pump system for cooling, heating and hot water supply provided by this utility model.
[0026] Explanation of reference numerals in the attached figures:
[0027] 1-Low-pressure compressor; 2-High-pressure compressor; 3-Three-way valve; 4-Hot water heat exchanger; 5-Second water pump; 6-Hot water tank; 7-Third water pump; 8-Solar collector; 9-Solenoid valve; 10-Second underground heat exchanger; 11-First underground heat exchanger; 12-First water pump; 13-Outdoor heat exchanger; 14-First expansion valve; 15-First check valve; 16-First intermediate heat exchanger; 19-Second intermediate heat exchanger; 20-Second expansion valve; 21-Indoor heat exchanger; 22-Four-way valve; 23-Second check valve. Detailed Implementation
[0028] The purpose of this invention is to provide a dual-stage compression ground source heat pump system for cooling, heating, and hot water supply, which integrates cooling, heating, and hot water production to improve system efficiency.
[0029] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings.
[0030] like Figure 1 As shown, this utility model provides a two-stage compression ground source heat pump system for cooling, heating, and hot water, which can achieve the following functions:
[0031] Refrigeration:
[0032] Refrigerant vapor is compressed into a medium-temperature, medium-pressure gas by the low-pressure compressor 1, mixes with the refrigerant gas in the first intermediate heat exchanger 16 for cooling, and then enters the high-pressure compressor 2 for compression into a high-temperature, high-pressure gas. At this time, the second port of the three-way valve 3 is open and the third port is closed. The high-pressure refrigerant gas enters the outdoor heat exchanger 13 through the four-way valve 22 for condensation and heat release. The heat is transferred by the first water pump 12 to the first underground heat exchanger 11 for release into the soil. The condensed refrigerant is divided into two paths. The first path directly enters the first intermediate heat exchanger 16, and the second path enters the first intermediate heat exchanger 16 for heat exchange after being throttled and cooled by the first expansion valve 14 and cooled by the first one-way valve 15. In this path, the refrigerant gas mixes with the medium-temperature, medium-pressure gas compressed by the low-pressure compressor 1, and the refrigerant liquid enters the second intermediate heat exchanger 19. It then passes through the second expansion valve 20 for throttling again and evaporates into refrigerant gas in the indoor heat exchanger 21, returning to the second intermediate heat exchanger 19 for heat absorption and flash evaporation, and then returns to the low-pressure compressor 1 through the four-way valve 22.
[0033] Because the average temperature of deep soil is relatively stable, generally around 12℃, in cooling mode, the outdoor heat exchanger 13 acts as a condenser, creating a heat exchange temperature difference with the soil. The first water pump 12 operates, transporting water (generally 30℃) cooled by heat exchange with the soil from the first buried heat exchanger 11 on the soil side to the outdoor heat exchanger 13 for condensation and heat release. The heated water (generally 35℃) returns to the first buried heat exchanger 11 to be further cooled by the soil. This process repeats, releasing heat.
[0034] Refrigerant diversion can recover some of the condensation heat, and on the other hand, the refrigerant mixes with the high-temperature and high-pressure gas discharged from the low-pressure compressor 1, reducing the suction temperature and pressure of the gas entering the high-pressure compressor 2 and improving the working efficiency of the high-pressure compressor 2.
[0035] In this process, heat absorption flash evaporation occurs when the low-temperature, low-pressure refrigerant gas enters the second intermediate heat exchanger 19, which lowers the temperature and pressure of the second intermediate heat exchanger 19. The refrigerant entering the second intermediate heat exchanger 19 from the first intermediate heat exchanger 16 is in the gas-liquid two-phase region on the pressure-enthalpy diagram. At this time, some of the refrigerant gas will reach the saturation temperature at this pressure, achieving a phase change from liquid to gas, similar to the effect of flash vaporization.
[0036] After the refrigerant evaporates and cools down in the indoor heat exchanger 21, it becomes low-temperature, low-pressure refrigerant vapor and flows into the second intermediate heat exchanger 19. The second intermediate heat exchanger 19 then absorbs heat from the medium-temperature, medium-pressure refrigerant flowing out of the first intermediate heat exchanger 16, further heating it and increasing the evaporation temperature and superheat. The second intermediate heat exchanger 19 also prevents liquid refrigerant from entering the low-pressure compressor 1, protecting the low-pressure compressor 1.
[0037] Heating:
[0038] Refrigerant vapor is compressed into a medium-temperature, medium-pressure gas by the low-pressure compressor 1, mixes with the refrigerant gas in the first intermediate heat exchanger 16 for cooling, and then enters the high-pressure compressor 2 for compression into a high-temperature, high-pressure gas. At this time, the second port of the three-way valve 3 is fully open and the third port is closed. The high-pressure refrigerant gas enters the indoor heat exchanger 21 through the four-way valve 22, condenses and releases heat, releasing heat into the indoor air. The condensed refrigerant is throttled and cooled by the second expansion valve 20 before entering the second intermediate heat exchanger 19. The condensed refrigerant is divided into two paths: the first path directly enters the first intermediate heat exchanger 16, and the second path is throttled and cooled by a branch formed by the first expansion valve 14 and the one-way valve 15 before entering the first intermediate heat exchanger 16 for heat exchange, where the refrigerant gas mixes with the medium-temperature, medium-pressure gas compressed by the low-pressure compressor 1. The refrigerant after heat exchange in the first intermediate heat exchanger 16 enters the outdoor heat exchanger 13 for evaporation and heat absorption. The cooling capacity is transported by the first water pump 12 to the first underground heat exchanger 11 for absorption from the soil. The evaporated refrigerant gas returns to the low-pressure compressor 1 via the four-way valve 22.
[0039] Cooling and hot water production:
[0040] Refrigerant vapor is compressed into a medium-temperature, medium-pressure gas by the low-pressure compressor 1, mixed with the refrigerant gas in the first intermediate heat exchanger 16 for cooling, and then enters the high-pressure compressor 2 for compression into a high-temperature, high-pressure gas. At this time, the second port of the three-way valve 3 is fully closed and the third port is fully open, allowing the high-pressure refrigerant gas to enter the hot water heat exchanger 4 for condensation and heat release. The heat is then released into the hot water tank 6 by the second water pump 5. The condensed refrigerant then enters the outdoor heat exchanger 13 through the second one-way valve 23 and the four-way valve 22 for secondary condensation and heat release. The heat is then transported by the first water pump 12 to the first underground heat exchanger 11 for release into the soil. After secondary condensation, the refrigerant is divided into two paths. The first path directly enters the first intermediate heat exchanger 16, and the second path enters the first intermediate heat exchanger 16 for heat exchange after being throttled and cooled by the first expansion valve 14 and the first one-way valve 15. In this process, the refrigerant gas mixes with the medium-temperature and medium-pressure gas compressed by the low-pressure compressor 1, and the refrigerant liquid enters the second intermediate heat exchanger 19. It is then throttled again by the second expansion valve 20 and evaporates into refrigerant gas by the indoor heat exchanger 21. It then returns to the second intermediate heat exchanger 19 to absorb heat and flash evaporate, and finally returns to the low-pressure compressor 1 through the four-way valve 22.
[0041] Heating and hot water production:
[0042] Refrigerant vapor is compressed into a medium-temperature, medium-pressure gas by the low-pressure compressor 1, mixes with the refrigerant gas in the first intermediate heat exchanger 16 for cooling, and then enters the high-pressure compressor 2 for compression into a high-temperature, high-pressure gas. At this time, the second port of the three-way valve 3 is fully closed and the third port is fully open, allowing the high-pressure refrigerant gas to enter the hot water heat exchanger 4 for condensation and heat release. The heat is then released into the hot water tank 6 by the second water pump 5. The refrigerant then enters the indoor heat exchanger 21 via the four-way valve 22 for secondary condensation and heat release, releasing heat into the indoor air. After secondary condensation, the refrigerant passes through the second expansion valve 20 for throttling and cooling before entering the second intermediate heat exchanger 19. The condensed refrigerant is divided into two paths: the first path directly enters the first intermediate heat exchanger 16, and the second path, after throttling and cooling via the branch formed by the first expansion valve 14 and the first one-way valve 15, enters the first intermediate heat exchanger 16 for heat exchange, where the refrigerant gas mixes with the medium-temperature, medium-pressure gas compressed by the low-pressure compressor 1. After passing through the first intermediate heat exchanger 16, the refrigerant enters the outdoor heat exchanger 13 to evaporate and absorb heat. The cooling capacity is then transported by the first water pump 12 to the first underground heat exchanger 11 for absorption from the soil. The evaporated refrigerant gas returns to the low-pressure compressor 1 via the four-way valve 22.
[0043] When the outdoor weather is sunny and the water temperature in the tank reaches the set temperature, the solar collector 8 and the third water pump 7 operate, the solenoid valve 9 opens, and the heated hot water is transported into the second underground heat exchanger 10 to exchange heat with the first underground heat exchanger 11 in a countercurrent manner, thereby increasing the outdoor evaporation temperature and pressure, improving the heating capacity, reducing the power consumption of the compressor, and improving the system performance.
[0044] In summary, the present invention integrates multiple functions such as cooling, heating and hot water production, thereby improving the working efficiency of the ground source heat pump system.
[0045] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.
Claims
1. A combined cooling, heating, and hot water supply system based on a two-stage compression ground source heat pump, characterized in that, include: Compressor, intermediate heat exchanger, underground heat exchanger, multiple other heat exchangers, valve assembly, and solar collector assembly; The compressor includes a low-pressure compressor (1) and a high-pressure compressor (2), with the outlet of the low-pressure compressor (1) connected to the inlet of the high-pressure compressor (2); The intermediate heat exchanger includes a first intermediate heat exchanger (16) and a second intermediate heat exchanger (19). The other heat exchangers include an outdoor heat exchanger (13) and an indoor heat exchanger (21). The first intermediate heat exchanger is connected to the outlet of the low-pressure compressor (1), the outdoor heat exchanger (13), and the second intermediate heat exchanger (19), respectively. The second intermediate heat exchanger (19) is connected to the indoor heat exchanger (21); The valve assembly includes a three-way valve (3) and a four-way valve (22); The first port of the three-way valve (3) is connected to the outlet of the high-pressure compressor (2), the second port of the three-way valve (3) is connected to the first port of the four-way valve (22), and the third port of the three-way valve (3) is connected to the solar thermal collector. The second port of the four-way valve (22) is connected to the second intermediate heat exchanger (19), the third port of the four-way valve (22) is connected to the inlet of the low-pressure compressor (1), and the fourth port of the four-way valve (22) is connected to the outdoor heat exchanger (13). The outdoor heat exchanger (13) is connected to the underground heat exchanger, and the underground heat exchanger is connected to the solar collector assembly.
2. The combined cooling, heating, and hot water supply system of the two-stage compression ground source heat pump according to claim 1, characterized in that, The buried heat exchanger includes: The first buried heat exchanger (11) is connected to the outdoor heat exchanger (13) and is used to release heat to the soil when the system is cooling, or to release cold energy to the soil when the system is heating. The second underground heat exchanger (10) is connected to the solar collector assembly and is used for countercurrent heat exchange with the first underground heat exchanger (11).
3. The combined cooling, heating, and hot water supply system of the two-stage compression ground source heat pump according to claim 2, characterized in that, The solar thermal collector module includes: Hot water heat exchanger (4) is connected to the third port of the three-way valve (3); The hot water tank (6) is connected in a loop to the hot water heat exchanger (4); The solar collector (8) is connected in a loop to the hot water tank (6); The second underground heat exchanger (10) is connected in parallel to the circuit formed by the solar collector (8) and the hot water tank (6).
4. The combined cooling, heating, and hot water supply system of the two-stage compression ground source heat pump according to claim 3, characterized in that, The valve assembly further includes: a first expansion valve (14) and a first check valve (15); The first expansion valve (14) and the first check valve (15) are connected in series to indirectly form a branch circuit; The branch line is connected in parallel to the connecting pipe between the outdoor heat exchanger (13) and the first intermediate heat exchanger (16), and / or, is connected in parallel to the connecting pipe between the second intermediate heat exchanger (19) and the first intermediate heat exchanger (16). The first one-way valve is located near the first intermediate heat exchanger (16) to restrict the cooling medium from flowing unidirectionally to the first intermediate heat exchanger (16).
5. The combined cooling, heating, and hot water supply system of the two-stage compression ground source heat pump according to claim 4, characterized in that, The valve assembly further includes a second expansion valve (20); the second expansion valve (20) is located between the second intermediate heat exchanger (19) and the indoor heat exchanger (21).
6. The combined cooling, heating, and hot water supply system of the two-stage compression ground source heat pump according to claim 5, characterized in that, The valve assembly also includes a second check valve (23); the second check valve (23) is located between the hot water heat exchanger (4) and the four-way valve (22).
7. The combined cooling, heating, and hot water supply system of a two-stage compression ground source heat pump according to any one of claims 3 to 6, characterized in that, The valve assembly also includes a solenoid valve (9). The solenoid valve (9) is located on the parallel branch of the second underground heat exchanger (10), specifically near the outlet of the hot water tank (6).
8. The combined cooling, heating, and hot water supply system of the two-stage compression ground source heat pump according to claim 7, characterized in that, It also includes the first water pump (12); The first water pump is located between the first underground heat exchanger (11) and the outdoor heat exchanger (13), specifically near the outlet of the outdoor heat exchanger (13).
9. The combined cooling, heating, and hot water supply system of the two-stage compression ground source heat pump according to claim 8, characterized in that, It also includes a second water pump (5); The second water pump is located between the hot water heat exchanger (4) and the hot water tank (6), specifically near the inlet of the hot water tank (6).
10. The combined cooling, heating, and hot water supply system of the two-stage compression ground source heat pump according to claim 9, characterized in that, It also includes a third water pump (7); The third water pump is located between the solar collector (8) and the hot water tank (6), specifically near the outlet of the hot water tank (6).