Air source and fuel gas hybrid heat pump system

Abstract

The invention discloses an air source and fuel gas hybrid heat pump system, and belongs to the technical field of heat supply. The system is provided with an air source heat pump, a direct-fired absorption heat pump, an energy storage water tank connected between the air source heat pump and the direct-fired absorption heat pump, and a plate heat exchanger connected between the direct-fired absorption heat pump and a heat consumer; the system further comprises a flue gas heat exchanger. An inlet of the heat exchanger is sequentially connected with the direct-fired absorption heat pump and the plate heat exchanger, and an outlet of the heat exchanger is connected with an inlet of the plate heat exchanger, so that a loop is formed; according to the direct-fired absorption heat pump air source heat pump system, an air source heat pump and a direct-fired absorption heat pump are organically combined, and efficient operation of the system under different load conditions is achieved by means of the dual-energy advantages of off-peak electricity and natural gas.

Description

Technical Field

[0001] The present invention relates to the technical field of heating, and in particular to an air source and gas hybrid heat pump system. Background Art

[0002] With the intensification of the global energy crisis and the enhancement of environmental protection awareness, the problems of high consumption and high pollution of traditional energy have become increasingly prominent, driving the urgent need for clean energy and efficient energy utilization technologies. Especially in the fields of building heating and hot water supply, although traditional gas boilers and electric heating equipment are technically mature, their energy utilization efficiency is relatively low, and their carbon emissions are relatively high, making it difficult to meet the requirements of modern society for energy conservation and emission reduction. Therefore, developing a new type of heating system that can not only efficiently utilize energy but also reduce environmental pollution has become the focus of current technological development.

[0003] As a clean energy technology, air source heat pumps have the characteristics of high efficiency and environmental protection. However, their heating efficiency decreases significantly in low-temperature environments, and they rely on electric drive, making it difficult to completely replace traditional gas equipment. Gas-fired absorption heat pumps, on the other hand, can utilize the high calorific value of fossil fuels such as natural gas to provide a stable heat source, but their energy efficiency ratio (COP) during independent operation is relatively low.

[0004] Therefore, based on the above problems, how to combine the advantages of air source heat pumps and gas-fired absorption heat pumps to form a hybrid heat pump system has become the key to solving the above problems. Summary of the Invention

[0005] The object of the present invention is to overcome the defects of the existing technology and provide an air source and gas hybrid heat pump system. By organically combining an air source heat pump and a direct-fired absorption heat pump, the dual energy advantages of off-peak electricity and natural gas are utilized to achieve the efficient operation of the system under different load conditions.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] The air source and gas hybrid heat pump system disclosed by the present invention includes:

[0008] An air source heat pump, a direct-fired absorption heat pump, a heat storage water tank connected between the air source heat pump and the direct-fired absorption heat pump, and a plate heat exchanger connected between the direct-fired absorption heat pump and the heat user; it also includes

[0009] A flue gas heat exchanger; its inlet is sequentially connected to the direct-fired absorption heat pump and the plate heat exchanger, and its outlet is connected to the inlet of the plate heat exchanger to form a loop;

[0010] Wherein, the inlet and outlet pipelines of the heat storage water tank are both communicated with the pipeline at the inlet of the flue gas heat exchanger.

[0011] Further, a parallel process is adopted for the solution circuit in the direct-fired absorption heat pump. Among them, the outlet of one absorber of the direct-fired absorption heat pump is connected to the high-temperature solution heat exchanger and the high-pressure generator in sequence through the dilute solution pipeline b, and the outlet of the other absorber is connected to the low-temperature solution heat exchanger and the low-pressure generator in sequence through the dilute solution pipeline b.

[0012] Further, the outlet of the high-pressure generator is connected to the inlet of the high-temperature solution heat exchanger through the concentrated solution pipeline c, the outlet of the low-pressure generator is connected to the inlet of the low-temperature solution heat exchanger through the concentrated solution pipeline c, and the outlets of the high-temperature solution heat exchanger and the low-temperature solution heat exchanger converge into one path through the concentrated solution pipeline c and are connected to the inlet of the absorber.

[0013] Further, the outlet of the low-pressure generator is connected to the inlet of the condenser II, the outlet of the condenser II is connected to the inlet of the evaporator II through the refrigerant pipeline d, and the outlet of the evaporator II is connected to the inlet of the absorber.

[0014] Further, the flue gas heat exchanger is connected to the high-pressure generator through a flue gas pipeline. The outlet of the plate heat exchanger is connected to the inlets of the absorber, the condenser II, and the flue gas heat exchanger in sequence through the cooling water pipeline h. The outlet of the flue gas heat exchanger is connected to the inlet of the plate heat exchanger through the hot water pipeline g. The inlet and outlet of the energy storage water tank on the cold water pipeline f are connected to the outlet cooling water pipeline h of the condenser II and the outlet cooling water pipeline h of the plate heat exchanger through a tee.

[0015] Further, the energy storage water tank is connected to the evaporator II through the cold water pipeline f, and a cold water valve is arranged on the cold water pipeline f.

[0016] Further, the high-pressure generator is connected to the burner and the water heater. The water heater is connected to the low-pressure generator through the refrigerant vapor pipeline e, and a refrigerant valve is arranged on the refrigerant vapor pipeline e between the water heater and the low-pressure generator.

[0017] Further, the water heater is connected to the cold water pipeline f of the energy storage water tank through the hot water pipeline g, and a hot water valve is arranged on the hot water pipeline g.

[0018] Further, a solution valve is arranged on the dilute solution pipeline b between the high-temperature solution heat exchanger and the absorber. The outlet of the absorber is connected to the inlet of the solution pump, and the outlet of the solution pump is connected to the inlet of the high-temperature solution heat exchanger.

[0019] Further, the air source heat pump has a condenser I. The refrigerant water outlet of the condenser I is connected to an expansion valve through a refrigerant water pipe a. A filter is provided on the pipeline between the condenser I and the expansion valve. The outlet of the expansion valve is connected to the inlet of an evaporator I. The outlet of the evaporator I is connected to the inlet of a compressor. The outlet of the compressor is connected to the inlet of the condenser I. The condenser I is connected to the energy storage water tank through a pipeline.

[0020] In the above technical solution, for the air source and gas hybrid heat pump system provided by the present invention, the beneficial effects are:

[0021] For the air source and gas hybrid heat pump system designed by the present invention, firstly, an energy storage water tank is connected between the air source heat pump and the direct-fired absorption heat pump, and a plate heat exchanger is connected between the direct-fired absorption heat pump and heat users, organically combining the air source heat pump and the direct-fired absorption heat pump;

[0022] Secondly, a flue gas heat exchanger inlet is sequentially connected to the direct-fired absorption heat pump and the plate heat exchanger, and the outlet is connected to the plate heat exchanger inlet to form a loop, and the inlet and outlet pipelines of the energy storage water tank are both communicated with the pipeline of the flue gas heat exchanger inlet;

[0023] This system can not only make full use of the condensation heat of the air source heat pump in series mode at high load to improve the energy efficiency of the gas absorption heat pump, but also flexibly distribute heat in parallel mode at low load to ensure the high efficiency and economy of the system. In addition, the system also introduces a flue gas waste heat recovery technology, further improving the energy utilization efficiency and reducing energy waste. Brief Description of the Drawings

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings.

[0025] Figure 1 It is the working principle diagram of the air source and gas hybrid heat pump system disclosed by the present invention.

[0026] Description of the reference numerals:

[0027] 1. Condenser I; 2. Low-pressure generator; 3. Filter; 4. Compressor; 5. Expansion valve; 6. Evaporator I; 7. Refrigerant valve; 8. Water heater; 9. Flue gas heat exchanger; 10. High-pressure generator; 11. Burner; 12. High-temperature solution heat exchanger; 13. Solution valve; 14. Evaporator II; 15. Refrigerant pump; 16. Low-temperature solution heat exchanger; 17. Solution pump; 18. Absorber; 19. Plate heat exchanger; 20. Energy storage water tank; 21. Hot water valve; 22. Cold water valve; 23. Condenser II; 24. Three-way

[0028] 100. Air source heat pump; 200. Direct-fired absorption heat pump

[0029] a. Refrigerant water pipe; b. Dilute solution pipeline; c. Concentrated solution pipeline; d. Refrigerant pipeline; e. Refrigerant vapor pipeline; f. Cold water pipeline; g. Hot water pipeline; h. Cooling water pipeline. Specific embodiments

[0030] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0031] See Figure 1 as shown;

[0032] An air source and gas hybrid heat pump system is invented, including: an air source heat pump 100, a direct-fired absorption heat pump 200, a flue gas heat exchanger 9, a plate heat exchanger 19 and an energy storage water tank 20;

[0033] The energy storage water tank 20 is connected between the air source heat pump 100 and the direct-fired absorption heat pump 200, the plate heat exchanger 19 is connected between the direct-fired absorption heat pump 200 and the heat user, the working medium uses an environmentally friendly refrigerant and lithium bromide solution, the inlet of the flue gas heat exchanger 9 is sequentially connected to the direct-fired absorption heat pump 200 and the plate heat exchanger 19, and the outlet is connected to the inlet of the plate heat exchanger 19, thus forming a loop. The inlet and outlet pipelines of the energy storage water tank 20 are both communicated with the pipeline at the inlet of the flue gas heat exchanger 9. That is to say, the inlet of the energy storage water tank 20 is communicated with the pipeline before the pipeline of the inlet of the flue gas heat exchanger 9 enters the direct-fired absorption heat pump 200, and the outlet of the energy storage water tank 20 is communicated with the pipeline after the pipeline of the inlet of the flue gas heat exchanger 9 exits the direct-fired absorption heat pump 200.

[0034] In a specific embodiment, see Figure 1 as shown, the air source heat pump 100 includes a condenser I 1, a filter 3, a compressor 4, an expansion valve 5 and an evaporator I 6;

[0035] The refrigerant water outlet of condenser Ⅰ1 is connected to expansion valve 5 through refrigerant water pipe a, and filter 3 is arranged on the pipe between condenser Ⅰ1 and expansion valve 5; the outlet of expansion valve 5 is connected to the inlet of evaporator Ⅰ6; the outlet of evaporator Ⅰ6 is connected to the inlet of compressor 4; the outlet of compressor 4 is connected to the inlet of condenser Ⅰ1; condenser Ⅰ1 is connected to energy storage water tank 20 through a pipe.

[0036] The direct-fired absorption heat pump 200 includes low-pressure generator 2, condenser Ⅱ23, absorber 18, evaporator Ⅱ14, high-pressure generator 10, high-temperature solution heat exchanger 12, low-temperature solution heat exchanger 16, water heater 8, burner 11, refrigerant valve 7, solution valve 13, hot water valve 21, cold water valve 22, refrigerant pump 15 and solution pump 17;

[0037] In the direct-fired absorption heat pump 200, the solution circuit adopts a parallel flow. One outlet of absorber 18 is sequentially connected to high-temperature solution heat exchanger 12 and high-pressure generator 10 through lean solution pipe b, and the other outlet of absorber 18 is sequentially connected to low-temperature solution heat exchanger 16 and low-pressure generator 2 through lean solution pipe b. Solution valve 13 is arranged on lean solution pipe b between high-temperature solution heat exchanger 12 and absorber 18. The outlet of absorber 18 is connected to the inlet of solution pump 17, and the outlet of solution pump 17 is connected to the inlet of high-temperature solution heat exchanger 12;

[0038] The outlet of high-pressure generator 10 is connected to the inlet of high-temperature solution heat exchanger 12 through concentrated solution pipe c, and the outlet of low-pressure generator 2 is connected to the inlet of low-temperature solution heat exchanger 16 through concentrated solution pipe c. The outlets of high-temperature solution heat exchanger 12 and low-temperature solution heat exchanger 16 converge into one path through concentrated solution pipe c and are connected to the inlet of absorber 18;

[0039] Burner 11 is connected to high-pressure generator 10. High-pressure generator 10 is connected to flue gas heat exchanger 9 through a flue gas pipe. High-pressure generator 10 is connected to water heater 8. Water heater 8 is connected to low-pressure generator 2 through refrigerant vapor pipe e. Refrigerant valve 7 is arranged on refrigerant vapor pipe e between water heater 8 and low-pressure generator 2. The outlet of low-pressure generator 2 is connected to the inlet of condenser Ⅱ23. The outlet of condenser 23 is connected to the inlet of evaporator Ⅱ14 through refrigerant pipe d. The outlet of evaporator Ⅱ14 is connected to the inlet of absorber 18. Refrigerant pump 15 is arranged on refrigerant pipe d at the outlet of evaporator Ⅱ14.

[0040] Energy storage water tank 20 is connected to evaporator Ⅱ14 through cold water pipe f. Cold water valve 22 is arranged on cold water pipe f. Water heater 8 is connected to cold water pipe f through hot water pipe g. Hot water valve 21 is arranged on hot water pipe g;

[0041] The outlet of the plate heat exchanger 19 is sequentially connected to the absorber 18, the condenser II 23, and the inlet of the flue gas heat exchanger 9 through the cooling water pipeline h, and the outlet of the flue gas heat exchanger 9 is connected to the inlet of the plate heat exchanger 19 through the hot water pipeline g; the inlet and outlet of the energy storage water tank 20 on the cold water pipeline f is connected to the outlet cooling water pipeline h of the condenser II 23 and the outlet cooling water pipeline h of the plate heat exchanger 19 through a tee 24.

[0042] In the above technical solution, an air source and gas hybrid heat pump system provided by the present invention, its working principle, and the operation mode of the system can be divided into a series hybrid operation mode and a parallel hybrid operation mode:

[0043] Series operation mode: When operating at high load, the hot water valve 21 is closed, the cold water valve 22, the refrigerant valve 7, and the solution valve 13 are opened. The air source heat pump 100 drives the compressor 4 by using off-peak electricity to generate refrigerant vapor, which enters the condenser I 1. The condensation heat generated in the condenser I 1 is stored in the hot water storage tank 20. The hot water storage tank 20 is connected to the evaporator II 14 of the direct-fired absorption heat pump 200. During the peak electricity period, the compression air source heat pump 100 is deactivated. The heat of the hot water storage tank 20 is all provided to the evaporator II 14 for the evaporation of the refrigerant. The chilled water that has provided the heat returns to the hot water storage tank 20 to complete the chilled water cycle; the cooling water is provided by the plate heat exchanger 19 and flows in a series process. After passing through the absorber 18 and the condenser II 23 in sequence, the temperature is increased, and then it enters the gas heat exchanger 9 and is further heated by the high-temperature flue gas generated by fuel combustion, and then returns to the plate heat exchanger 19 through the hot water pipeline g to provide heat for users.

[0044] Parallel operation mode: When operating at low load, the hot water valve 21 is closed, the cold water valve 22, the refrigerant valve 7, and the solution valve 13 are opened. According to the heat distribution principle of 3:2, the condensation heat generated by the air source heat pump 100 and the direct-fired absorption heat pump 200 provide heat for users at the same time. Specifically, the condensation heat generated by the air source heat pump 100 is divided into two paths. 2 / 5 of the heat is used to provide the energy required for evaporation for the evaporator II 14 of the direct-fired absorption heat pump 200, and 3 / 5 of the heat directly enters the flue gas heat exchanger 9 after being mixed with the cooling water through the tee 24, and is heated and then enters the plate heat exchanger 19 through the hot water pipeline g to provide heat for users.

[0045] If the hot water in the hot water storage tank 20 is exhausted or insufficient to maintain the operation of the absorption heat pump, close the cold water valve 22, the refrigerant valve 7, and the solution valve 13, and open the hot water valve 21. The cold water circuit is replaced by the hot water circuit. At this time, only the water heater 8, the high-pressure generator 10, and the hot water circuit in the direct-fired absorption heat pump 200 are operating. The refrigerant vapor generated by the high-pressure generator 10 condenses into refrigerant water on the tube bundle of the water heater 8, and the refrigerant water directly returns to the high-pressure generator 10 to complete the cycle; the hot water enters the flue gas heat exchanger 9 through the hot water valve 21 and is further heated, and then enters the plate heat exchanger 19 through the hot water pipeline g to provide heat for users;

[0046] If domestic hot water needs to be produced simultaneously, the inlet and outlet valves for domestic water can be opened. At this time, hot water is output from both hot water circuits.

[0047] Producing domestic hot water while heating is a special form of the direct-fired heat pump. Generally, the heat for producing domestic hot water should not exceed 15% of the total heat.

[0048] This system organically combines an air-source heat pump with a direct-fired absorption heat pump, and utilizes the dual energy advantages of off-peak electricity and natural gas to achieve the efficient operation of the system under different load conditions. This system can not only make full use of the condensation heat of the air-source heat pump in series mode at high loads to improve the energy efficiency of the gas absorption heat pump, but also flexibly distribute heat in parallel mode at low loads to ensure the high efficiency and economy of the system. In addition, the system also introduces flue gas waste heat recovery technology to further improve the energy utilization efficiency and reduce energy waste;

[0049] Only some exemplary embodiments of the present invention have been described above by way of illustration. Undoubtedly, for those of ordinary skill in the art, the described embodiments can be modified in various different ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. An air source and gas hybrid heat pump system, characterized in that, Comprising: an air source heat pump (100), a direct-fired absorption heat pump (200), a heat storage water tank (20) connected between the air source heat pump (100) and the direct-fired absorption heat pump (200), and a plate heat exchanger (19) connected between the direct-fired absorption heat pump (200) and a heat user; further comprising a flue gas heat exchanger (9); its inlet is sequentially connected to the direct-fired absorption heat pump (200) and the plate heat exchanger (19), and its outlet is connected to the inlet of the plate heat exchanger (19) so as to form a loop; wherein, the inlet and outlet pipelines of the heat storage water tank (20) are both communicated with the pipeline at the inlet of the flue gas heat exchanger (9).

2. The air source and gas hybrid heat pump system according to claim 1, characterized in that: In the direct-fired absorption heat pump (200), the solution circuit adopts a parallel flow. Among them, the outlet of one absorber (18) of the direct-fired absorption heat pump (200) is sequentially connected to a high-temperature solution heat exchanger (12) and a high-pressure generator (10) through a dilute solution pipeline b, and the outlet of the other absorber (18) is sequentially connected to a low-temperature solution heat exchanger (16) and a low-pressure generator (2) through the dilute solution pipeline b.

3. The air source and gas hybrid heat pump system according to claim 2, characterized in that: The outlet of the high-pressure generator (10) is connected to the inlet of the high-temperature solution heat exchanger (12) through a concentrated solution pipeline c, the outlet of the low-pressure generator (2) is connected to the inlet of the low-temperature solution heat exchanger (16) through the concentrated solution pipeline c, and the outlets of the high-temperature solution heat exchanger (12) and the low-temperature solution heat exchanger (16) converge into one path through the concentrated solution pipeline c and are connected to the inlet of the absorber (18).

4. The air source and gas hybrid heat pump system according to claim 2 or 3, characterized in that: The outlet of the low-pressure generator (2) is connected to the inlet of a condenser II (23), the outlet of the condenser II (23) is connected to the inlet of an evaporator II (14) through a refrigerant pipeline d, and the outlet of the evaporator II (14) is connected to the inlet of the absorber (18).

5. The air source and gas hybrid heat pump system according to claim 4, characterized in that: The flue gas heat exchanger (9) is connected to the high-pressure generator (10) through a flue gas pipeline, the outlet of the plate heat exchanger (19) is sequentially connected to the absorber (18), the condenser II (23) and the inlet of the flue gas heat exchanger (9) through a cooling water pipeline h, the outlet of the flue gas heat exchanger (9) is connected to the inlet of the plate heat exchanger (19) through a hot water pipeline g, and the inlet and outlet cold water pipelines f of the heat storage water tank (20) are connected to the outlet cooling water pipeline h of the condenser II (23) and the outlet cooling water pipeline h of the plate heat exchanger (19) through a tee (24).

6. The air source and gas hybrid heat pump system according to claim 4, characterized in that: The energy storage water tank (20) is connected to the evaporator II (14) through a cold water pipeline f, and a cold water valve (22) is arranged on the cold water pipeline f.

7. The air source and gas hybrid heat pump system according to claim 2 or 3, characterized in that: The high-pressure generator (10) is connected to the burner (11) and the water heater (8), the water heater (8) is connected to the low-pressure generator (2) through a refrigerant vapor pipeline e, and a refrigerant valve (7) is arranged on the refrigerant vapor pipeline e between the water heater (8) and the low-pressure generator (2).

8. The air source and gas hybrid heat pump system according to claim 7, characterized in that: The water heater (8) is connected to the cold water pipeline f of the energy storage water tank (20) through a hot water pipeline g, and a hot water valve (21) is arranged on the hot water pipeline g.

9. The air source and gas hybrid heat pump system according to claim 2, characterized in that: A solution valve (13) is arranged on the dilute solution pipeline b between the high-temperature solution heat exchanger (12) and the absorber (18), the outlet of the absorber (18) is connected to the inlet of the solution pump (17), and the outlet of the solution pump (17) is connected to the inlet of the high-temperature solution heat exchanger (12).

10. The air source and gas hybrid heat pump system according to claim 1, characterized in that: The air source heat pump (100) has a condenser I (1), the refrigerant water outlet of the condenser I (1) is connected to the expansion valve (5) through a refrigerant water pipeline a, a filter (3) is arranged on the pipeline between the condenser I (1) and the expansion valve (5), the outlet of the expansion valve (5) is connected to the inlet of the evaporator I (6), the outlet of the evaporator I (6) is connected to the inlet of the compressor (4), the outlet of the compressor (4) is connected to the inlet of the condenser I (1), and the condenser I (1) is connected to the energy storage water tank (20) through a pipeline.

Images