An absorption-compression high-temperature heat pump system for recovering waste heat

Abstract

This utility model discloses an absorption-compression high-temperature heat pump system for recovering waste heat. Its two-stage compression heat pump system includes high and low pressure compressors, a compression system condenser and evaporator, and a medium- and low-temperature waste heat recovery evaporator. The high-temperature absorption heat pump system includes a high-temperature absorber, a high-temperature solution heat exchanger, a high-temperature generator, an evaporative condenser, and a high-temperature evaporator. The low-temperature absorption heat pump system includes a low-temperature solution heat exchanger, a low-temperature absorber, a low-temperature generator, a low-temperature condenser, and an evaporative condenser. The absorption heat pump-driven heat source water system includes a compression system condenser, high and low temperature generators, and a high-temperature evaporator. The waste heat recovery water system includes a compression system evaporator and a low-temperature condenser. Its structure is compact, the heat flow path is clear, and internal heat is recycled. It recovers waste heat while achieving efficient thermal coupling between the compression and absorption stages, increasing the heat generation temperature. It has a wide range of applications and meets the needs of energy saving and high-temperature heating.

Description

Technical Field

[0001] This utility model relates to an absorption-compression high-temperature heat pump system for recovering waste heat, belonging to the field of heat pump technology. Background Technology

[0002] Against the backdrop of increasing demands for industrial energy conservation and waste heat recovery, absorption heat pumps and compression heat pumps, as two typical types of heat energy enhancement devices, have been widely used in various fields. Absorption heat pumps utilize low-grade heat sources to drive solution circulation, recovering medium- and low-temperature waste heat at 40~100℃, but their waste heat recovery efficiency (heating capacity / waste heat capacity) is relatively low, generally around 0.4-0.5. Compression heat pumps, on the other hand, rely on electricity to drive a compressor to increase refrigerant pressure, exhibiting higher efficiency, but their output temperature is limited, failing to meet the demands of some high-temperature operating conditions. Therefore, the combination of absorption and compression heat pump systems, i.e., absorption-compression hybrid heat pump systems, has gradually become an important development direction in the field of industrial high-temperature heat utilization in recent years.

[0003] Existing absorption-compression heat pump systems still have certain problems in structural design and thermal coupling methods. For example, CN115950112A discloses a two-stage absorption-compression thermally coupled heat pump system, which exchanges heat between the condenser of the second compression cycle and the low-pressure evaporator of the absorption system, and simultaneously exchanges heat between the condenser of the absorption system and the evaporator of the compression system to achieve energy transfer between the two cycles. The problems are as follows: First, it cannot achieve waste heat recovery and utilization. Second, this system uses the refrigerant of the compression cycle to directly exchange heat with the working fluid of the absorption cycle; if refrigerant leakage or temperature control failure occurs, it will lead to operational risks. Third, the pressure of the condenser in the compression system is usually in the range of 1.0~1.5 MPa, while the operating pressure of the evaporator in the absorption system is generally only 0.02 MPa, a difference of nearly two orders of magnitude, further increasing the risk of refrigerant leakage. If the high-pressure refrigerant directly enters the low-pressure absorption system, its structural strength and sealing performance need to be significantly improved, which will increase the equipment size and cost. Fourth, the existing systems have a relatively simple heating path and lack a multi-stage heating mechanism for hot water. They typically rely on only one heat exchange to output hot water, resulting in a limited increase in heat production temperature. This makes them unsuitable for industrial applications requiring hot water above 100°C, such as food drying and pulp dewatering. Furthermore, the existing systems have weak absorption and quality improvement capabilities for low- and medium-temperature waste heat from industrial cooling water and circulating water (below 60°C), limiting their applicability and economic efficiency. Additionally, while coupling the evaporator (using vapor compression refrigeration) with the condenser (using absorption refrigeration) can improve the condenser's cooling effect, it reduces the system's waste heat recovery capacity. Utility Model Content

[0004] The purpose of this invention is to overcome the shortcomings of the existing technology and provide an absorption-compression high-temperature heat pump system for recovering waste heat.

[0005] The technical solution provided by this utility model is as follows: an absorption-compression high-temperature heat pump system for recovering waste heat, characterized in that it includes a two-stage compression heat pump system, a high-temperature stage absorption heat pump system, a low-temperature stage absorption heat pump system, an absorption heat pump driven heat source water system, and a waste heat recovery and utilization water system.

[0006] The two-stage compression heat pump system includes a low-pressure stage compressor, a high-pressure stage compressor, a compression system condenser, a medium-low temperature waste heat recovery evaporator, a compression system evaporator, and valves;

[0007] The high-temperature absorption heat pump system includes a high-temperature absorber, a high-temperature solution heat exchanger, an evaporator-condenser, a high-temperature evaporator, pumps, and valves.

[0008] The low-temperature absorption heat pump system includes a low-temperature solution heat exchanger, a low-temperature absorber, a low-temperature generator, a low-temperature condenser, an evaporative condenser, pumps, and valves;

[0009] The absorption heat pump driven heat source water system includes a compression system condenser, a high-temperature generator, a low-temperature generator, a high-temperature evaporator, a pump, and valves;

[0010] The waste heat recovery and utilization water system includes a compression system evaporator, a low-temperature condenser, and a pump;

[0011] The outlet of the low-pressure stage compressor is connected to the inlet of the high-pressure stage compressor. The outlet of the high-pressure stage compressor is connected to one inlet of the compression system condenser. One outlet of the compression system condenser is connected to one inlet of the medium-low temperature waste heat recovery evaporator via an intermediate pressure solenoid valve and an intermediate pressure throttle valve. One outlet of the medium-low temperature waste heat recovery evaporator is connected to the inlet of the high-pressure stage compressor. The two inlets of the medium-low temperature waste heat recovery evaporator are medium-low temperature waste heat inlets, and the two outlets of the medium-low temperature waste heat recovery evaporator are medium-low temperature waste heat outlets. One outlet of the compression system condenser is connected to one inlet of the compression system evaporator via a low-pressure solenoid valve and a low-pressure throttle valve. One outlet of the compression system evaporator is connected to the inlet of the low-pressure stage compressor.

[0012] One outlet of the high-temperature absorber is connected to the upper inlet of the high-temperature solution heat exchanger. The lower outlet of the high-temperature solution heat exchanger is connected to one inlet of the high-temperature generator through a high-temperature throttling valve. One outlet of the high-temperature generator is connected to the lower inlet of the high-temperature solution heat exchanger through a high-temperature solution pump. The upper outlet of the high-temperature solution heat exchanger is connected to one inlet of the high-temperature absorber.

[0013] The three outlets of the high-temperature generator are connected to one inlet of the evaporator-condenser. One outlet of the evaporator-condenser is connected to one inlet of the high-temperature evaporator via a high-temperature solvent pump. One outlet of the high-temperature evaporator is connected to the three inlets of the high-temperature absorber.

[0014] One outlet of the low-temperature absorber is connected to the upper inlet of the low-temperature solution heat exchanger; the lower outlet of the low-temperature solution heat exchanger is connected to one inlet of the low-temperature generator through a low-temperature throttling valve; one outlet of the low-temperature generator is connected to the lower inlet of the low-temperature solution heat exchanger through a low-temperature solution pump; and the upper outlet of the low-temperature solution heat exchanger is connected to one inlet of the low-temperature absorber. The three outlets of the low-temperature generator are connected to one inlet of the low-temperature condenser; one outlet of the low-temperature condenser is connected to the inlet of the low-temperature solvent pump; the outlet of the low-temperature solvent pump is connected to two inlets of the evaporator-condenser; and the two outlets of the evaporator-condenser are connected to the three inlet of the low-temperature absorber.

[0015] The two outlets of the condenser in the compression system are connected to the right valve port of the first three-way valve via the first water pump. The left valve port of the first three-way valve is connected to the two inlets of the high-temperature evaporator. The two inlets of the high-temperature evaporator are connected to the left valve port of the second three-way valve. The right valve port of the second three-way valve is connected to the two inlets of the condenser in the compression system. The lower valve port of the first three-way valve is connected to the two inlets of the high-temperature generator. The two outlets of the high-temperature generator are connected to the two inlets of the low-temperature generator. The two outlets of the low-temperature generator are connected to the lower valve port of the second three-way valve.

[0016] The two outlets of the evaporator in the compression system are connected to the two inlets of the low-temperature condenser via a second water pump, and the two outlets of the low-temperature condenser are connected to the two inlets of the evaporator in the compression system.

[0017] The two inlets of the low-temperature absorber are connected to the water source, and the two outlets of the low-temperature absorber are connected to the two inlets of the high-temperature generator; the two outlets of the high-temperature generator are connected to the high-temperature hot water output terminal.

[0018] The beneficial effects of this utility model are as follows: This utility model includes a two-stage compression heat pump system, a high-temperature absorption heat pump system, a low-temperature absorption heat pump system, an absorption heat pump driven heat source water system, and a waste heat recovery and utilization water system. It has a compact structure, a clear heat flow path, and internal heat recycling capabilities. It can achieve efficient thermal coupling between the compression section and the absorption section, fully recover and utilize medium and low temperature waste heat, increase the heat generation temperature, expand the applicable operating conditions range, and meet the comprehensive needs of modern industrial energy conservation and high-temperature heating through multi-stage heating and waste heat cascade recovery.

[0019] This invention utilizes an absorption heat pump driven heat source water system, consisting of a compression system condenser, a first water pump, a first three-way valve, a second three-way valve, a high-temperature generator, a low-temperature generator, and a high-temperature evaporator, to absorb the high-temperature condensation heat released by the two-stage compression heat pump system. This heat is then used as the driving heat source for both the high-temperature and low-temperature absorption heat pump systems, creating an effective internal heat circulation path. This achieves tiered utilization of energy within the system, significantly reducing external heating demand and improving thermal efficiency.

[0020] This invention achieves high-temperature hot water output of over 100℃ through two heating stages: a low-temperature absorption heat pump system and a high-temperature absorption heat pump system. It is particularly suitable for industrial high-temperature heating applications such as food drying and pulp dewatering, thus overcoming the limitation of traditional heat pump systems in terms of output temperature.

[0021] This invention utilizes an absorption heat pump-driven heat source water system, consisting of a compression system condenser, a first water pump, a first three-way valve, a second three-way valve, a high-temperature generator, a low-temperature generator, and a high-temperature evaporator. The heat generated by the two-stage compression heat pump system is transferred to the heat source water system using water as the heat transfer medium. First, the heat is transferred to the high-temperature absorber, serving as the heat source for the high-temperature absorption heat pump. Then, the cooled hot water enters the low-temperature absorber, serving as the heat source for the low-temperature absorption heat pump, thus achieving tiered utilization of heat. Furthermore, by using water as the heat coupling medium between the compression and absorption systems and establishing an indirect heat exchange path through a water circulation channel and water pump, pressure isolation and safe coupling are achieved during the heat transfer process. The water circuit system constructed in this system, when in a closed state, typically maintains an operating pressure between 0.1 and 0.3 MPa, which is much lower than that of the compressed refrigerant system and slightly higher than that of the absorption system. This not only effectively buffers the pressure difference between the two sides but also has good adjustability and operational stability, thereby significantly improving the overall safety, sealing reliability, and service life of the system.

[0022] This invention replaces the traditional direct coupling method of refrigerant with indirect heat exchange via water channels, effectively avoiding the risk of instability in the absorption solution caused by refrigerant leakage or abnormal thermal control.

[0023] This invention features a medium-low temperature waste heat recovery evaporator, which can effectively absorb and utilize medium-low temperature waste heat of 40~60℃. It is particularly suitable for waste heat resources such as cooling water commonly used in industrial production, thus broadening the applicable operating conditions of heat pumps.

[0024] This invention utilizes a waste heat recovery and utilization water system consisting of a compression system evaporator, a second water pump, and a low-temperature condenser. The waste heat released by the low-temperature condenser in the low-temperature absorption heat pump system is recovered and transported to the compression system evaporator to provide heat for the refrigerant evaporation process. This achieves energy cascade recovery and reuse in different temperature ranges within the system, significantly improving the overall system's thermal efficiency and economy.

[0025] This invention, through a rational design of the water flow direction, first utilizes the heat released by the low-temperature generator in the low-temperature absorption heat pump system to perform primary heating of cold water. Then, the heated hot water is introduced into the high-temperature generator to further absorb the high-grade heat released therein, completing secondary heating, and finally producing high-temperature hot water for industrial applications, realizing multi-stage heat source utilization and hot water quality improvement. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of this utility model.

[0027] In the diagram: 1. Low-pressure stage compressor; 2. High-pressure stage compressor; 3. Compression system condenser; 4-1. Intermediate pressure solenoid valve; 4-2. Low-pressure solenoid valve; 5-1. Intermediate pressure throttle valve; 5-2. Low-pressure throttle valve; 5-3. High-temperature throttle valve; 5-4. Low-temperature throttle valve; 6. Medium- and low-temperature waste heat recovery evaporator; 7. Compression system evaporator; 8-1. First water pump; 8-2. Second water pump; 9-1. First three-way valve; 9-2. Second three-way valve; 10. High-temperature absorber; 11-1. High-temperature solution heat exchanger; 11-2. Low-temperature solution heat exchanger; 12-1. High-temperature solution pump; 12-2. Low-temperature solution pump; 13. High-temperature generator; 14. Low-temperature absorber; 15. Low-temperature generator; 16. Low-temperature condenser; 17-1. Low-temperature solvent pump; 17-2. High-temperature solvent pump; 18. Evaporator condenser; 19. High-temperature evaporator. Detailed Implementation

[0028] The specific embodiments of this utility model will be further described in detail below with reference to the accompanying drawings:

[0029] like Figure 1 As shown, an absorption-compression high-temperature heat pump system for recovering waste heat includes five parts: a two-stage compression heat pump system, a high-temperature absorption heat pump system, a low-temperature absorption heat pump system, an absorption heat pump driven heat source water system, and a waste heat recovery and utilization water system.

[0030] The two-stage compression heat pump system includes a low-pressure stage compressor 1, a high-pressure stage compressor 2, a compression system condenser 3, an intermediate pressure solenoid valve 4-1, a low-pressure solenoid valve 4-2, an intermediate pressure throttling valve 5-1, a low-pressure throttling valve 5-2, a medium-low temperature waste heat recovery evaporator 6, and a compression system evaporator 7.

[0031] The high-temperature absorption heat pump system includes a high-temperature absorber 10, a high-temperature solution heat exchanger 11-1, a high-temperature solution pump 12-1, a high-temperature throttling valve 5-3, a high-temperature generator 13, a high-temperature solvent pump 17-2, an evaporator-condenser 18, and a high-temperature evaporator 19.

[0032] The low-temperature absorption heat pump system includes a low-temperature solution heat exchanger 11-2, a low-temperature solution pump 12-2, a low-temperature throttling valve 5-4, a low-temperature absorber 14, a low-temperature generator 15, a low-temperature condenser 16, a low-temperature solvent pump 17-1, and an evaporator-condenser 18.

[0033] The absorption heat pump driven heat source water system includes a compression system condenser 3, a first water pump 8-1, a first three-way valve 9-1, a second three-way valve 9-2, a high-temperature generator 13, a low-temperature generator 15, and a high-temperature evaporator 19.

[0034] The waste heat recovery and utilization water system includes a compression system evaporator 7, a second water pump 8-2, and a low-temperature condenser 16.

[0035] The outlet of low-pressure stage compressor 1 is connected to the inlet of high-pressure stage compressor 2. The outlet of high-pressure stage compressor 2 is connected to one inlet of compression system condenser 3. One outlet of compression system condenser 3 is connected to both the inlet of intermediate pressure solenoid valve 4-1 and the inlet of low-pressure solenoid valve 4-2. The outlet of intermediate pressure solenoid valve 4-1 is connected to the inlet of intermediate pressure throttle valve 5-1. The outlet of intermediate pressure throttle valve 5-1 is connected to one inlet of medium-low temperature waste heat recovery evaporator 6. One outlet of medium-low temperature waste heat recovery evaporator 6 is connected to the inlet of high-pressure stage compressor 2. The two inlets of medium-low temperature waste heat recovery evaporator 6 are medium-low temperature waste heat inlets, and the two outlets of medium-low temperature waste heat recovery evaporator 6 are medium-low temperature waste heat outlets. The outlet of low-pressure solenoid valve 4-2 is connected to the inlet of low-pressure throttle valve 5-2. The outlet of low-pressure throttle valve 5-2 is connected to one inlet of compression system evaporator 7. One outlet of compression system evaporator 7 is connected to the inlet of low-pressure stage compressor 1.

[0036] One outlet of the high-temperature absorber 10 is connected to the upper inlet of the high-temperature solution heat exchanger 11-1. The lower outlet of the high-temperature solution heat exchanger 11-1 is connected to the inlet of the high-temperature throttle valve 5-3. The outlet of the high-temperature throttle valve 5-3 is connected to one inlet of the high-temperature generator 13. One outlet of the high-temperature generator 13 is connected to the inlet of the high-temperature solution pump 12-1. The outlet of the high-temperature solution pump 12-1 is connected to the lower inlet of the high-temperature solution heat exchanger 11-1. The upper outlet of the high-temperature solution heat exchanger 11-1 is connected to one inlet of the high-temperature absorber 10.

[0037] The three outlets of the high-temperature generator 13 are connected to one inlet of the evaporator-condenser 18. One outlet of the evaporator-condenser 18 is connected to the inlet of the high-temperature solvent pump 17-2. The outlet of the high-temperature solvent pump 17-2 is connected to one inlet of the high-temperature evaporator 19. One outlet of the high-temperature evaporator 19 is connected to the three inlets of the high-temperature absorber 10.

[0038] One outlet of the cryogenic absorber 14 is connected to the upper inlet of the cryogenic solution heat exchanger 11-2. The lower outlet of the cryogenic solution heat exchanger 11-2 is connected to the inlet of the cryogenic throttle valve 5-4. The outlet of the cryogenic throttle valve 5-4 is connected to one inlet of the cryogenic generator 15. One outlet of the cryogenic generator 15 is connected to the inlet of the cryogenic solution pump 12-2. The outlet of the cryogenic solution pump 12-2 is connected to the lower inlet of the cryogenic solution heat exchanger 11-2. The upper outlet of the cryogenic solution heat exchanger 11-2 is connected to one inlet of the cryogenic absorber 14. Three outlets of the cryogenic generator 15 are connected to one inlet of the cryogenic condenser 16. One outlet of the cryogenic condenser 16 is connected to the inlet of the cryogenic solvent pump 17-1. The outlet of the cryogenic solvent pump 17-1 is connected to two inlets of the evaporator-condenser 18. Two outlets of the evaporator-condenser 18 are connected to three inlets of the cryogenic absorber 14.

[0039] The two outlets of the condenser 3 in the compression system are connected to the inlet of the first water pump 8-1. The outlet of the first water pump 8-1 is connected to the right valve port of the first three-way valve 9-1. The left valve port of the first three-way valve 9-1 is connected to the two inlets of the high-temperature evaporator 19. The two inlets of the high-temperature evaporator 19 are connected to the left valve port of the second three-way valve 9-2. The right valve port of the second three-way valve 9-2 is connected to the two inlets of the condenser 3 in the compression system. The lower valve port of the first three-way valve 9-1 is connected to the two inlets of the high-temperature generator 13. The two outlets of the high-temperature generator 13 are connected to the two inlets of the low-temperature generator 15. The two outlets of the low-temperature generator 15 are connected to the lower valve port of the second three-way valve 9-2.

[0040] The two outlets of the evaporator 7 in the compression system are connected to the inlet of the second water pump 8-2. The outlet of the second water pump 8-2 is connected to the two inlets of the low-temperature condenser 16. The two outlets of the low-temperature condenser 16 are connected to the two inlets of the evaporator 7 in the compression system.

[0041] The two inlets of the low-temperature absorber 14 are connected to a water source, and the two outlets of the low-temperature absorber 14 are connected to the two inlets of the high-temperature generator 10. The two outlets of the high-temperature generator 10 are connected to the high-temperature hot water output terminal.

[0042] The two-stage compression heat pump system generates high-temperature heat. The low-temperature waste heat recovery evaporator 6, operating at intermediate pressure, can absorb medium-low temperature hot water at around 50°C, thus recovering and utilizing the waste heat from this hot water. The specific operation mode is as follows:

[0043] The refrigerant vapor evaporated at intermediate pressure from the low-pressure stage compressor 1 mixes with the intermediate-pressure refrigerant vapor from one outlet of the low-temperature waste heat recovery evaporator 6, and enters the high-pressure stage compressor 2. After being compressed by the high-pressure stage compressor 2, the high-pressure, high-temperature refrigerant vapor is output and enters the compression system condenser 3 through one inlet. It condenses and releases heat to become high-pressure, high-temperature refrigerant liquid. It is divided into two parts through one inlet and one outlet of the compression system condenser 3. One part is throttled and depressurized to intermediate pressure through the intermediate pressure solenoid valve 4-1 and the intermediate pressure throttling valve 5-1 and enters the low-temperature waste heat recovery evaporator 6 through one inlet to absorb waste heat from the low-temperature hot water at about 50°C. The low-temperature hot water at about 50°C enters the low-temperature waste heat recovery evaporator 6 through the second inlet and exchanges heat with the refrigerant vapor. The water after heat exchange flows out from the second outlet of the low-temperature waste heat recovery evaporator 6. The refrigerant liquid after heat exchange evaporates into refrigerant vapor. Another path passes through the low-pressure solenoid valve 4-2 and the low-pressure throttling valve 5-2. Under the action of the low-pressure throttling valve 5-2, the refrigerant liquid is cooled and depressurized by the throttling effect, becoming a low-temperature and low-pressure liquid. The refrigerant enters the evaporator 7 of the compression system through one inlet and evaporates. After absorbing heat, it becomes a low-temperature and low-pressure refrigerant gas. It flows back to the low-pressure stage compressor 1 through one outlet of the evaporator 7 of the compression system. The low-pressure stage compressor 1 compresses it into refrigerant vapor at an intermediate pressure, and the above cycle is repeated.

[0044] The absorption heat pump-driven heat source water system extracts heat from the condenser 3 of the compression system of the two-stage compression heat pump system. Part of this heat is used as the driving heat source for both the high-temperature and low-temperature absorption heat pump systems, and part is exchanged with the high-temperature evaporator 19 of the high-temperature absorption heat pump system, causing the refrigerant in the high-temperature evaporator 19 to become high-temperature, high-pressure refrigerant vapor. The specific operating mode is as follows:

[0045] After heat exchange, the low-temperature water enters the compressor system condenser 3 through the second inlet of the compressor system condenser 3. In the compressor system condenser 3, it absorbs the heat released by the condensation of the refrigerant and flows out through the second outlet of the compressor system condenser 3. Driven by the first water pump 8-1, it enters the right valve port of the first three-way valve 9-1. The high-temperature hot water entering from the right valve port of the first three-way valve 9-1 is divided into two paths. One path flows out from the left valve port of the first three-way valve 9-1 and flows into the high-temperature evaporator 19 through the second inlet of the high-temperature evaporator 19. It exchanges heat with the refrigerant in the high-temperature evaporator 19, turning the refrigerant in the high-temperature evaporator 19 into high-temperature and high-pressure refrigerant vapor. The low-temperature water after heat exchange flows from the second outlet of the high-temperature evaporator 19 into the left valve port of the second three-way valve 9-2. Another path flows out from the lower valve port of the first three-way valve 9-1, enters the high-temperature generator 13 through the second inlet, and drives the high-temperature generator to work. The medium-temperature hot water after heat exchange flows out from the second outlet of the high-temperature generator 13, enters the low-temperature absorber 15 through the second inlet, and drives the low-temperature absorber 15 to work. The hot water after heat exchange flows out from the second outlet of the low-temperature absorber 15, enters the lower valve port of the second three-way valve 9-2, merges with the low-temperature water after heat exchange at the left valve port of the second three-way valve 9-2, and flows out from the right valve port of the second three-way valve 9-2. It then enters the compression system condenser 3 through the second inlet, and repeats the above cycle.

[0046] The heat generated by the two-stage vapor compression heat pump system is transferred to the high-temperature absorber via a water-based heat transfer medium, driven by an absorption heat pump. This water serves as the heat source for the high-temperature absorption heat pump, driving it to operate. The cooled hot water then enters the low-temperature absorber, acting as the heat source for the low-temperature absorption heat pump, thus achieving cascaded utilization of heat. The working principle of the high-temperature absorption heat pump system is as follows:

[0047] Solution Circulation: The dilute solution is heated by a high-temperature heat source in the high-temperature generator 13, generating refrigerant vapor and becoming a concentrated solution. This concentrated solution flows out from one outlet of the high-temperature generator 13, is pressurized by the high-temperature solution pump 12-1, and flows into the high-temperature solution heat exchanger 11-1 through its lower inlet for heat exchange. After heat exchange, the concentrated solution flows out from the upper outlet of the high-temperature solution heat exchanger 11-1 and flows into the high-temperature absorber 10 through one inlet, absorbing the refrigerant vapor generated in the high-temperature evaporator 19, releasing heat during the absorption process. The dilute solution after absorbing the refrigerant vapor flows out from one outlet of the high-temperature absorber 10, flows into the high-temperature solution heat exchanger 11-1 through its upper side to exchange heat with the concentrated solution, and then flows out from the lower side of the high-temperature solution heat exchanger 11-1. After being throttled and depressurized by the high-temperature throttling valve 5-3, it flows back into the high-temperature generator 13 through one inlet, generating refrigerant vapor again, completing the solution circulation. This cycle is repeated.

[0048] Refrigerant cycle: The refrigerant vapor generated by the high-temperature generator 13 flows out from the three outlets of the high-temperature generator 13, flows into the evaporator condenser 18 through one inlet, condenses and releases heat in the evaporator condenser 18, and the condensed refrigerant water is sent into the high-temperature evaporator 19 through one outlet of the evaporator condenser 18 via the high-temperature solvent pump 17-2 and one outlet of the high-temperature evaporator 19. In the high-temperature evaporator 19, the refrigerant absorbs the heat of the hot water, and the evaporated water vapor flows out from one outlet of the high-temperature evaporator 19, flows into the high-temperature absorber 10 through the three inlets, and is absorbed, thus completing the solvent cycle. The above cycle is repeated.

[0049] Working principle of low-temperature absorption heat pump system:

[0050] Solution circulation: The dilute solution is heated by a medium-temperature heat source in the low-temperature generator 15 to produce refrigerant vapor, which then becomes a concentrated solution. The concentrated solution flows out from one outlet of the low-temperature generator 15 and is pressurized and driven by the low-temperature solution pump 12-2. It then flows into the low-temperature solution heat exchanger 11-2 at the lower inlet for heat exchange. After heat exchange, the concentrated solution flows out from the upper outlet of the low-temperature solution heat exchanger 11-2 and flows into the low-temperature absorber 14 at one inlet to absorb the refrigerant vapor generated in the evaporator-condenser 18. The absorption process releases heat. The dilute solution after absorbing refrigerant vapor flows out from one outlet of the low-temperature absorber 14, flows into the low-temperature solution heat exchanger 11-2 from the upper side to exchange heat with the concentrated solution, and the dilute solution after heat exchange flows out from the lower side of the low-temperature solution heat exchanger 11-2. After being throttled and depressurized by the low-temperature throttling valve 5-4, it flows into the low-temperature generator 15 from one inlet to regenerate refrigerant vapor, completing the solution circulation, and repeating the above cycle.

[0051] Refrigerant cycle: The refrigerant vapor generated by the low-temperature generator 15 flows out from the three outlets of the low-temperature generator 15, flows into the low-temperature condenser 16 through the one inlet of the low-temperature condenser 16 and condenses and releases heat. The condensed refrigerant water is sent into the evaporator 18 through the two inlets of the evaporator condenser 18 by the low-temperature solvent pump 17-1. In the evaporator condenser 18, it exchanges heat with the high-temperature refrigerant vapor generated by the high-temperature generator 13. The evaporated water vapor flows out from the two outlets of the evaporator condenser 18 and flows into the low-temperature absorber 14 through the three inlets of the low-temperature absorber 14 for absorption, completing the solvent cycle. The above cycle is repeated.

[0052] The waste heat generated by the low-temperature condenser 16 of the low-temperature absorption heat pump system is absorbed by the waste heat recovery and utilization water system and then transferred to the evaporator 7 of the compression system. This provides heat for the refrigerant evaporation and heat absorption in the evaporator 7 of the compression system. The specific operation mode is as follows:

[0053] High-temperature hot water flows into the evaporator 7 of the compression system through the two inlets. After absorbing heat from the refrigerant in the compression system, the water temperature decreases and flows out from the two outlets of the evaporator 7. Driven by the second water pump 8-2, the hot water flows into the low-temperature condenser 16 through the two inlets, where it exchanges heat with the refrigerant in the high-temperature absorption subsystem. After the heat exchange, the water temperature decreases and flows out from the low-temperature condenser 16 through the two outlets. The hot water then flows back into the evaporator 7 of the compression system through the two inlets, and the cycle repeats.

[0054] Cold water enters the low-temperature generator 14 of the low-temperature absorption heat pump system, where it absorbs the heat released by the low-temperature generator 14 to complete the first temperature rise. Then, it flows out through the two outlets of the low-temperature generator 14 and enters the high-temperature generator 10 to further absorb the high-temperature heat released by the high-temperature generator 10 to complete the second temperature rise. Finally, the high-temperature hot water produced is used for industrial heating applications.

[0055] It should be understood that any parts not described in detail in this specification belong to the prior art. The above embodiments are merely descriptions of preferred embodiments of this utility model and are not intended to limit the scope of this utility model. Various modifications and improvements to the technical solutions of this utility model made by those skilled in the art without departing from the spirit of this utility model should fall within the protection scope defined by the claims of this utility model.

Claims

1. An absorption-compression high temperature heat pump system recovering waste heat, characterized by, It includes a two-stage compression heat pump system, a high-temperature absorption heat pump system, a low-temperature absorption heat pump system, an absorption heat pump driven heat source water system, and a waste heat recovery and utilization water system; The two-stage compression heat pump system includes a low-pressure stage compressor, a high-pressure stage compressor, a compression system condenser, a medium-low temperature waste heat recovery evaporator, a compression system evaporator, and valves; The high-temperature absorption heat pump system includes a high-temperature absorber, a high-temperature solution heat exchanger, an evaporator-condenser, a high-temperature evaporator, pumps, and valves. The low-temperature absorption heat pump system includes a low-temperature solution heat exchanger, a low-temperature absorber, a low-temperature generator, a low-temperature condenser, an evaporative condenser, pumps, and valves; The absorption heat pump driven heat source water system includes a compression system condenser, a high-temperature generator, a low-temperature generator, a high-temperature evaporator, a pump, and valves; The waste heat recovery and utilization water system includes a compression system evaporator, a low-temperature condenser, and a pump; The outlet of the low-pressure stage compressor is connected to the inlet of the high-pressure stage compressor. The outlet of the high-pressure stage compressor is connected to one inlet of the compression system condenser. One outlet of the compression system condenser is connected to one inlet of the medium-low temperature waste heat recovery evaporator via an intermediate pressure solenoid valve and an intermediate pressure throttle valve. One outlet of the medium-low temperature waste heat recovery evaporator is connected to the inlet of the high-pressure stage compressor. The two inlets of the medium-low temperature waste heat recovery evaporator are medium-low temperature waste heat inlets, and the two outlets of the medium-low temperature waste heat recovery evaporator are medium-low temperature waste heat outlets. One outlet of the compression system condenser is connected to one inlet of the compression system evaporator via a low-pressure solenoid valve and a low-pressure throttle valve. One outlet of the compression system evaporator is connected to the inlet of the low-pressure stage compressor. One outlet of the high-temperature absorber is connected to the upper inlet of the high-temperature solution heat exchanger. The lower outlet of the high-temperature solution heat exchanger is connected to one inlet of the high-temperature generator through a high-temperature throttling valve. One outlet of the high-temperature generator is connected to the lower inlet of the high-temperature solution heat exchanger through a high-temperature solution pump. The upper outlet of the high-temperature solution heat exchanger is connected to one inlet of the high-temperature absorber. The three outlets of the high-temperature generator are connected to one inlet of the evaporator-condenser. One outlet of the evaporator-condenser is connected to one inlet of the high-temperature evaporator via a high-temperature solvent pump. One outlet of the high-temperature evaporator is connected to the three inlets of the high-temperature absorber. One outlet of the low-temperature absorber is connected to the upper inlet of the low-temperature solution heat exchanger; the lower outlet of the low-temperature solution heat exchanger is connected to one inlet of the low-temperature generator through a low-temperature throttling valve; one outlet of the low-temperature generator is connected to the lower inlet of the low-temperature solution heat exchanger through a low-temperature solution pump; and the upper outlet of the low-temperature solution heat exchanger is connected to one inlet of the low-temperature absorber. The three outlets of the low-temperature generator are connected to one inlet of the low-temperature condenser; one outlet of the low-temperature condenser is connected to the inlet of the low-temperature solvent pump; the outlet of the low-temperature solvent pump is connected to two inlets of the evaporator-condenser; and the two outlets of the evaporator-condenser are connected to the three inlet of the low-temperature absorber. The two outlets of the condenser in the compression system are connected to the right valve port of the first three-way valve via the first water pump. The left valve port of the first three-way valve is connected to the two inlets of the high-temperature evaporator. The two inlets of the high-temperature evaporator are connected to the left valve port of the second three-way valve. The right valve port of the second three-way valve is connected to the two inlets of the condenser in the compression system. The lower valve port of the first three-way valve is connected to the two inlets of the high-temperature generator. The two outlets of the high-temperature generator are connected to the two inlets of the low-temperature generator. The two outlets of the low-temperature generator are connected to the lower valve port of the second three-way valve. The two outlets of the evaporator in the compression system are connected to the two inlets of the low-temperature condenser via a second water pump, and the two outlets of the low-temperature condenser are connected to the two inlets of the evaporator in the compression system. The two inlets of the low-temperature absorber are connected to the water source, and the two outlets of the low-temperature absorber are connected to the two inlets of the high-temperature generator; the two outlets of the high-temperature generator are connected to the high-temperature hot water output terminal.

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