Condensation heat recovery type high-temperature absorption heat pump system and heating method

Abstract

The invention discloses a condensation heat recovery type high-temperature absorption heat pump system and a heating method. The condensation heat recovery type high-temperature absorption heat pump system comprises an absorption heat pump unit and a compression heat pump unit. The absorption heat pump unit comprises a low-temperature generator, a low-temperature condenser, a high-temperature evaporator, a high-temperature absorber and a condensation generator; a steam outlet of the low-temperature generator is connected with an inlet of the low-temperature condenser, an outlet of the low-temperature condenser is connected with an inlet of the high-temperature evaporator through the pump I, and a steam outlet of the high-temperature evaporator is connected with a steam inlet of the high-temperature absorber; a high-temperature condenser is arranged in the internal space of the high-temperature evaporator, and the high-temperature condenser is communicated with a refrigerant channel of the compression type heat pump unit; according to the device, double-temperature-level heat energy is prepared through staged compression, the heating capacity of the system can be remarkably reduced, and the problem that a traditional heating type absorption heat pump is low in efficiency is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of heat pumps, and particularly relates to a condensation heat recovery type high-temperature absorption heat pump system and a heating method. Background Art

[0002] Energy problems and environmental problems are two major challenges for the sustainable development of today's society. Heat pump technology upgrades the grade of heat from industrial waste heat or the environment, and outputs low-grade thermal energy for reuse. It can not only efficiently utilize energy, but also reduce waste heat waste, bringing considerable economic benefits.

[0003] Typical heat pump technologies can be divided into compression heat pumps and absorption heat pumps. Compression heat pumps require high-grade electrical energy input, and the main way of electricity production in China depends on thermal power, which requires a large amount of fossil fuels. Absorption heat pumps use thermal energy as the driving force and utilize the absorption characteristics of the solution to transfer energy from a low-temperature heat source to a high-temperature heat source. Among them, the absorption heat pump with the output heat temperature lower than the driving heat source temperature is called the first type of absorption heat pump, also known as a heat-increasing heat pump. The absorption heat pump with the output heat temperature higher than the driving heat source temperature is called the second type of absorption heat pump, also known as a temperature-rising heat pump.

[0004] In the related prior art, the compression heat pump has the problems of high operating efficiency but high energy consumption. The absorption heat pump has the problems of large consumption of low-grade thermal energy and low efficiency. For example, a prior art provides an absorption compression heat pump (publication number CN111397246B), which adopts a new process and can meet the heating or cooling requirements under a wide range of air temperature changes in five operating modes. However, the driving thermal energy required by this system is large, and the compressor energy consumption is high. The two heat pump technologies have different characteristics in terms of efficiency, adaptability, and energy consumption type. How to effectively combine the advantages of the two heat pump technologies to reduce the driving thermal energy of the system, improve the operating efficiency, and effectively produce high-temperature thermal energy is one of the key problems in the current heat pump technology research that needs to be solved urgently. Summary of the Invention

[0005] The purpose of the present invention is to solve the problems existing in the above-mentioned prior art, and provide a condensation heat recovery type high-temperature absorption heat pump system and a heating method. This device can significantly reduce the heating amount of the system and produce high-temperature thermal energy by staged compression to produce double-temperature thermal energy, and solve the problem of low efficiency existing in traditional temperature-rising absorption heat pumps.

[0006] One of the objectives of the present invention is to provide a condensation heat recovery type high-temperature absorption heat pump system, which includes an absorption heat pump unit and a compression heat pump unit; the absorption heat pump unit includes a low-temperature generator, a low-temperature condenser, a high-temperature evaporator, a high-temperature absorber and a condensation generator; the steam outlet of the low-temperature generator is connected to the inlet of the low-temperature condenser, the outlet of the low-temperature condenser is connected to the inlet of the high-temperature evaporator via pump I, and the steam outlet of the high-temperature evaporator is connected to the steam inlet of the high-temperature absorber; a high-temperature condenser is arranged in the internal space of the high-temperature evaporator, and the high-temperature condenser is communicated with the refrigerant channel of the compression heat pump unit; the condensation generator includes a solution channel and a refrigerant channel for heat exchange, and the refrigerant channel of the condensation generator is connected to the refrigerant channel of the compression heat pump unit; the solution inlet of the high-temperature absorber is connected to the solution outlet of the low-temperature generator; the solution outlet of the high-temperature absorber is connected to the inlet of the solution channel of the condensation generator; the compression heat pump unit is used to absorb the heat energy of the air and the steam condensation heat of the absorption heat pump unit, and produce high-temperature heat energy to provide the latent heat of vaporization required for water evaporation in the high-temperature evaporator and the heat required for solution generation in the condensation generator.

[0007] As a preferred solution, the absorption heat pump unit further includes a solution heat exchanger, which includes a dilute solution channel and a concentrated solution channel for heat exchange. The inlet of the dilute solution channel of the solution heat exchanger is connected to the solution outlet of the high-temperature absorber, the outlet of the dilute solution channel of the solution heat exchanger is connected to the inlet of the solution side channel of the condensation generator via a solution throttling component, and the outlet of the solution side channel of the condensation generator is connected to the solution inlet of the low-temperature generator; the inlet of the concentrated solution channel of the solution heat exchanger is connected to the solution outlet of the low-temperature generator via pump II, and the outlet of the concentrated solution channel of the solution heat exchanger is connected to the solution inlet of the high-temperature absorber.

[0008] As a preferred solution, the compression heat pump unit includes a low-temperature evaporator, an air source evaporator, a working medium regenerator, a low-pressure compressor, a high-temperature condenser, a high-pressure compressor and a condensation generator; The working medium regenerator includes a liquid channel and a gas channel for heat exchange; the low-temperature evaporator is arranged inside the low-temperature condenser, the high-temperature condenser is arranged below the inlet of the high-temperature evaporator, the outlet of the low-temperature evaporator is connected to the inlet of the gas channel of the working medium regenerator via the air source evaporator, the outlet of the gas channel of the working medium regenerator is connected to the inlet of the low-pressure compressor, and the outlet of the low-pressure compressor is divided into two branches; the first branch is connected to the inlet of the high-temperature condenser, the outlet of the high-temperature condenser is connected to the inlet of the liquid channel of the working medium regenerator; the outlet of the liquid channel of the working medium regenerator is connected to the inlet of the low-temperature evaporator via a first throttling component; the second branch is connected to the inlet of the high-pressure compressor, the outlet of the high-pressure compressor is connected to the inlet of the refrigerant channel of the condensation generator, and the outlet of the refrigerant channel of the condensation generator is connected to the solution inlet of the low-temperature evaporator via a second throttling component.

[0009] As a preferred solution, a spraying member I is provided at the inlet of the high-temperature evaporator. The spraying member I is located in the internal space of the high-temperature evaporator and is disposed above the high-temperature condenser.

[0010] As a preferred solution, a heater is provided inside the low-temperature generator for providing heating quantity by an external heat source.

[0011] As a preferred solution, a heat exchanger is provided inside the high-temperature absorber. A spraying member II is provided at the dilute solution inlet of the high-temperature absorber. The heat exchanger is located below the spraying member II.

[0012] As a preferred solution, the solution heat exchanger, the condensation generator, and the working medium regenerator are any one or several of a plate heat exchanger, a double-pipe heat exchanger, or a shell-and-tube heat exchanger.

[0013] As a preferred solution, the air-source evaporator is a finned-tube heat exchanger.

[0014] The second object of the present invention is to provide a heating method for a condensation heat recovery type high-temperature absorption heat pump system, including the following steps: The refrigerant working medium of the compression type heat pump unit sequentially passes through the steam heat of the recovery absorption type heat pump unit and absorbs the heat energy of the outside air to form a low-temperature and low-pressure steam, and then compresses the low-temperature and low-pressure steam into a superheated refrigerant steam. The superheated refrigerant steam is divided into two paths. One path of the refrigerant steam passes through the high-temperature condenser to provide the latent heat of vaporization required for the evaporation of water in the high-temperature evaporator; the other path of the refrigerant steam is further compressed into a high-temperature and high-pressure superheated refrigerant steam. The high-temperature and high-pressure superheated refrigerant steam exchanges heat with the dilute solution in the high-temperature absorber. The liquid refrigerant passing through the high-temperature condenser and the liquid refrigerant of the condensation generator become refrigerant working media with the same pressure after passing through the throttling member, and then enter the low-temperature evaporator to exchange heat with the water vapor in the low-temperature condenser.

[0015] As a preferred solution, the concentrated solution in the low-temperature generator of the absorption type heat pump unit is sent to the high-temperature absorber by a pump II for realizing external heat supply through heat exchange. The concentrated solution absorbs the water vapor provided by the high-temperature evaporator to form a dilute solution, and then exchanges heat with the concentrated solution from the low-temperature generator through the solution heat exchanger. Then, the discharged dilute solution undergoes a cascade heating process to generate water vapor and enters the low-temperature condenser to exchange heat with the compression type heat pump unit, and finally forms liquid water and is sent to the high-temperature evaporator by a pump I.

[0016] Beneficial effects First, through structural optimization and improvement, the present invention includes two major parts: a compression heat pump unit and an absorption heat pump unit. Through the organic integration of the above two major parts, the technical advantages of the two heat pump unit systems are combined. According to the different characteristics of the two heat pump units in terms of efficiency, adaptability, and energy consumption type, the driving heat energy of the heat pump system is reduced, the operating efficiency is improved, and high-temperature heat energy is effectively produced, reducing the energy consumption of the system and improving the heating efficiency of the heat pump system. This system has remarkable energy-saving effects, stable and reliable operation, and broad application prospects.

[0017] Second, this solution also provides a heating method for a condensation heat recovery type high-temperature absorption heat pump system. By combining with the above-mentioned heat pump system with a specific improved structure, through the process of staged compression of the working fluid and the process of stepped generation of the dilute solution, high-temperature heat energy is produced to provide building heating or industrial heating, recovering the condensation heat of the absorption heat pump unit and utilizing the air heat energy in the high-temperature environment. By the process of staged compression, double-temperature heat energy is produced to provide the heating amount required for the high-temperature evaporator and part of the heating amount required for the solution generation. The dilute solution first absorbs the condensation heat of the compression heat pump unit through the condensation generator and then absorbs the heating amount of the external heat source through the low-temperature generator, thereby realizing the stepped heating and generation process of the dilute solution. By recovering the condensation heat of the traditional absorption heat pump and the high-temperature environment air heat energy, the purpose of significantly reducing the heating amount obtained from the outside of the system is achieved, and the problem of low efficiency existing in the traditional temperature-rising type absorption heat pump is solved. Brief Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0019] Figure 1 It is a schematic diagram of the structural principle of the heat pump system of the present invention; Reference numerals in the figure: 1, low-temperature generator; 2, low-temperature condenser; 3, pump I; 4, high-temperature evaporator; 41, spraying part I; 5, high-temperature absorber; 51, spraying part II; 52, heat exchanger; 6, solution heat exchanger; 7, condensation generator; 8, solution throttling component; 9, pump II; 10, low-pressure compressor; 11, high-temperature condenser; 12, high-pressure compressor; 13, working fluid regenerator; 14, first throttling component; 15, low-temperature evaporator; 16, air source evaporator; 17, second throttling component. Detailed Embodiments

[0020] The present invention will be specifically described below through exemplary embodiments. However, it should be understood that, without further description, the elements, structures, and features in one embodiment can also be beneficially combined with those in other embodiments.

[0021] It should be noted that: Unless otherwise defined, the technical terms or scientific terms used herein should have the ordinary meaning understood by those of ordinary skill in the art to which the present invention pertains. The words such as "a", "an", or "the" used in the specification and claims of the present invention for patent application do not express a limitation of quantity, but rather indicate the existence of at least one. The words such as "comprising" or "including" point out that the elements or objects appearing before "comprising" or "including" cover the elements or objects listed after "comprising" or "including" and their equivalents, but do not exclude other elements or objects having the same functions.

[0022] As shown in the figure, this embodiment provides a condensation heat recovery type high-temperature absorption heat pump system, which includes two parts: an absorption heat pump unit and a compression heat pump unit that can achieve heat exchange. Among them, the compression heat pump unit adopts a two-stage compression heat pump unit. The compression heat pump unit can recover the steam condensation heat of the absorption heat pump unit and absorb the heat energy of the external air, and is used to produce high-grade heat energy and provide the latent heat of vaporization and solution generation heat required by the absorption heat pump unit. This solution fully integrates the compression heat pump unit and the absorption heat pump unit, combines the specific advantages of the two heat pump units, improves the operating efficiency of the heat pump system, and reduces the energy consumption of the system.

[0023] In a typical embodiment of the present invention, the absorption heat pump unit includes a low-temperature generator 1, a low-temperature condenser 2, a pump I 3, a high-temperature evaporator 4, a high-temperature absorber 5, a solution heat exchanger 6, a condensation generator 7, a solution throttling component 8, and a pump II 9.

[0024] Among them, the low-temperature generator 1 includes a solution inlet, a water vapor outlet, and a solution outlet. Preferably, the water vapor outlet is arranged at the top of the low-temperature generator 1, and the solution outlet is arranged at the bottom of the low-temperature generator 1. A heater is arranged inside the low-temperature generator 1. The heater is used to heat the dilute salt solution contained inside the low-temperature generator 1 by absorbing low-grade heat from the outside, and at the same time generate steam and send it to the low-temperature condenser 2 for condensation. After the dilute salt solution in the low-temperature generator 1 evaporates, it becomes a concentrated salt solution and is sent to the solution heat exchanger 6 through the pump II 9. It should be noted that the heater arranged inside the low-temperature generator 1 is passed through by a heating medium and heat is provided by an external heat source. The external heat source can adopt low-grade heat sources such as solar energy and industrial waste heat, or can also be energy or heat sources such as fuel oil, gas, or steam.

[0025] In this embodiment, a low-temperature evaporator 15 is arranged in the internal space of the low-temperature condenser 2. The inlet and outlet of the low-temperature evaporator 15 are connected to the refrigerant channel of the compression heat pump unit. The water vapor inlet of the low-temperature condenser 2 is connected to the top water vapor outlet of the low-temperature generator 1. The outlet of the low-temperature condenser 2 is connected to the inlet of the high-temperature evaporator 4 through the pump I 3. The pump I 3 is a circulating pump for refrigerant water. Inside the low-temperature condenser 2, water vapor is condensed into liquid refrigerant water, and its condensation heat is absorbed by the refrigerant working medium passing through the inside of the low-temperature evaporator 15. The liquid low-temperature and low-pressure refrigerant water is lifted to a high-temperature and high-pressure state of refrigerant water under the action of the pump I 3 and is pumped into the internal space of the high-temperature evaporator 4.

[0026] In this solution, the high-temperature evaporator 4 includes a refrigerant water inlet and a water vapor outlet. A spray member I 41 is arranged at the refrigerant water inlet of the high-temperature evaporator 4. Preferably, the water vapor outlet of the high-temperature evaporator 4 is located at the top of the high-temperature evaporator 4. The high-temperature condenser 11 is located in the internal space of the high-temperature evaporator 4 and is placed below the spray member I 41. The inlet and outlet of the high-temperature condenser 11 are connected to the refrigerant channel of the compression heat pump unit. The refrigerant water droplets sprayed by the spray member I 41 fall on the high-temperature condenser 11 to absorb the heat of the refrigerant working medium passing through the inside of the high-temperature condenser 11 and then vaporize to generate water vapor. The water vapor is discharged through the water vapor outlet of the high-temperature evaporator 4 and enters the high-temperature absorber 5. Preferably, the spray member I 41 is provided with a plurality of spray heads and is distributed above the high-temperature condenser 11.

[0027] The following is an explanation of the high-temperature absorber 5. The high-temperature absorber 5 includes a water vapor inlet, a solution inlet, and a solution outlet. The water vapor inlet of the high-temperature absorber 5 is connected to the water vapor outlet of the high-temperature evaporator 4. Preferably, the solution outlet is arranged at the bottom of the high-temperature absorber 5. A spray member II 51 is arranged at the solution inlet. A heat exchanger 52 is arranged in the internal space of the high-temperature absorber 5. The function of the heat exchanger 52 is to introduce hot water or other media. Preferably, the heat exchanger 52 is a falling film heat exchanger. The spray member II 51 is provided with a plurality of spray heads and is distributed above the heat exchanger 52. The solution inlet of the high-temperature absorber 5 is connected to the outlet of the pump II 9 through the solution channel I of the solution heat exchanger 6, so as to spray the concentrated salt solution sent by the pump II 9 through the spray member II 51 into the internal space of the high-temperature absorber 5. The sprayed concentrated salt solution will absorb the water vapor entering the internal space of the high-temperature absorber 5. After the water vapor is absorbed, heat will be released and a dilute salt solution will be formed. The released heat is used to heat the hot water or other heating media passing through the inside of the heat exchanger 52, thereby raising the temperature of the user water or the heating media, for generating high-temperature hot water by heating hot water or other liquid media, providing building heating or industrial heating. The solution outlet end of the high-temperature absorber 5 is connected to the solution channel II of the solution heat exchanger 6.

[0028] In this solution, the solution channels I and II of the solution heat exchanger 6 can achieve heat exchange. The inlet of the solution channel I is connected to the outlet of the pump II 9, and the pump II 9 is a solution circulation pump. The outlet of the solution channel I is connected to the solution inlet of the high-temperature absorber 5. The concentrated salt solution sent by the low-temperature generator 1 is introduced into the solution channel I. The inlet of the solution channel II is connected to the bottom solution outlet of the high-temperature absorber 5, and the outlet of the solution channel II is connected to the solution channel inlet of the condensation generator 7. The dilute salt solution sent by the bottom of the high-temperature absorber 5 is introduced into the solution channel II. The dilute salt solution sent by the high-temperature absorber 5 heats the concentrated salt solution sent by the low-temperature generator 1, and the dilute salt solution cools down while the concentrated salt solution warms up.

[0029] In this embodiment, it further includes a condensation generator 7. The solution channel and the refrigerant working medium channel for heat exchange are provided in the condensation generator 7. The inlet of the solution channel of the condensation generator 7 is connected to the outlet of the solution channel II of the solution heat exchanger 6 through the solution throttling component 8. The function of the solution throttling component 8 is to throttle and depressurize the high-pressure dilute salt solution into a low-pressure dilute salt solution. The low-pressure dilute salt solution enters the condensation generator 7 for heating. Specifically, the low-pressure dilute salt solution absorbs the heat of the high-temperature and high-pressure refrigerant working medium passing through the refrigerant channel of the condensation generator 7. The outlet of the solution channel of the condensation generator 7 is connected to the solution inlet of the low-temperature generator 1. The dilute salt solution enters the low-temperature generator 1 for flashing, so as to separate and form a concentrated salt solution and water vapor. The concentrated salt solution returns to the high-temperature absorber 5 again after passing through the pump II 9 and the solution heat exchanger 6, while the water vapor is sent to the internal space of the low-temperature condenser 2. The inlet and outlet of the refrigerant channel of the condensation generator 7 are respectively connected to the refrigerant working medium channel of the absorption heat pump unit.

[0030] Specifically, the absorption heat pump unit includes a low-temperature generator 1, a low-temperature condenser 2, a pump I 3, a high-temperature evaporator 4, a high-temperature absorber 5, a solution heat exchanger 6, a condensation generator 7, a solution throttling component 8, and a pump II 9. The top steam outlet of the low-temperature generator 1 is connected to the inlet of the low-temperature condenser 2. The outlet of the low-temperature condenser 2 is connected to the spray member I 41 at the inlet of the high-temperature evaporator 4 through the pump I 3. The spray member I 41 is located above the high-temperature condenser 11 in the internal space of the low-temperature condenser 2. The steam outlet of the high-temperature evaporator 4 is connected to the steam inlet of the high-temperature absorber 5. The inlet of the solution channel II of the solution heat exchanger 6 is connected to the bottom solution outlet of the high-temperature absorber 5. The outlet of the solution channel II of the solution heat exchanger 6 is connected to the solution channel inlet of the condensation generator 7 through the solution throttling component 8. The outlet of the solution channel of the condensation generator 7 is connected to the solution inlet of the low-temperature generator 1. The inlet of the solution channel I of the solution heat exchanger 6 is connected to the solution outlet of the low-temperature generator 1 through the pump II 9. The outlet of the solution channel I of the solution heat exchanger 6 is connected to the spray member II 51 at the solution inlet of the high-temperature absorber 5. The spray member II 51 is located above the heat exchanger 52 in the internal space of the high-temperature absorber 5.

[0031] The following is an explanation of the compression heat pump unit: The compression heat pump unit includes a low-temperature evaporator 15, an air-source evaporator 16, a working medium regenerator 13, a low-pressure compressor 10, a high-temperature condenser 11, a high-pressure compressor 12, a condensation generator 7, a first throttling component 14, and a second throttling component 17; among them, the condensation generator 7 is a common component of the compression heat pump unit and the absorption heat pump unit.

[0032] In the present invention, the low-temperature evaporator 15 is placed inside the low-temperature condenser 2. Preferably, the low-temperature evaporator 15 is located at the lower position of the low-temperature condenser 2. The low-temperature evaporator 15 is used to condense the water vapor entering the internal space of the low-temperature condenser 2 into liquid water, and the liquid refrigerant working medium inside the low-temperature evaporator 15 absorbs heat and becomes a gaseous refrigerant working medium. The heat absorbed by the refrigerant working medium in the low-temperature evaporator 15 comes from the heat released by the condensation of water vapor. The inlet of the low-temperature evaporator 15 is connected to the outlet of the liquid channel of the working medium regenerator 13 through the first throttling component 14, and the outlet of the low-temperature evaporator 15 is connected to the inlet of the air-source evaporator 16, which is used to stepwise heat the liquid refrigerant into a gaseous refrigerant.

[0033] In this embodiment, the outlet of the air-source evaporator 16 is connected to the inlet of the gas channel of the working medium regenerator 13. The gaseous refrigerant working medium passes through the air-source evaporator 16, absorbs the air heat energy of the external ambient air, and then enters the gas channel of the working medium regenerator 13.

[0034] The following is an explanation of the working medium regenerator 13: The gas channel and the liquid channel of the working medium regenerator 13 can achieve heat exchange. Among them, the inlet of the gas channel of the working medium regenerator 13 is connected to the outlet of the air-source evaporator 16, the outlet of the gas channel of the working medium regenerator 13 is connected to the inlet of the low-pressure compressor 10, the inlet of the liquid channel of the working medium regenerator 13 is connected to the outlet of the high-temperature condenser 11, and the outlet of the liquid channel of the working medium regenerator 13 is connected to the inlet of the low-temperature evaporator 15 through the first throttling component 14, which is used to condense the higher-pressure gaseous refrigerant into a higher-pressure liquid refrigerant through the action of the high-temperature condenser 11. The working medium regenerator 13 is used to cool the high-pressure liquid before entering the first throttling component 14 with the gaseous refrigerant coming from the air-source evaporator 16, so that the liquid refrigerant in the liquid channel of the working medium regenerator 13 is subcooled and the refrigerant vapor in the gas channel is superheated.

[0035] In this embodiment, the inlet of the low-pressure compressor 10 is connected to the gas channel outlet of the working medium regenerator 13. The outlet of the low-pressure compressor 10 is divided into two branches. One branch is connected to the inlet of the high-temperature condenser 11. The high-temperature condenser 11 is placed in the sealed space of the high-temperature evaporator 4 and is located directly below the spray member I 41. A part of the refrigerant vapor from the outlet of the low-pressure compressor 10 enters the high-temperature condenser 11 to provide the latent heat of vaporization required for the water evaporation in the high-temperature evaporator 4. The other branch is connected to the suction port of the high-pressure compressor 12. The exhaust port of the high-pressure compressor 12 is connected to the refrigerant working medium channel inlet of the condensation generator 7, which is used to secondarily compress another part of the refrigerant working medium from the outlet of the low-pressure compressor 10 into high-temperature and high-pressure superheated refrigerant vapor, thus realizing the staged compression process of the refrigerant vapor.

[0036] The refrigerant working medium channel outlet of the condensation generator 7 is connected to the second throttling member 17. The condensation generator 7 is used to condense the high-temperature and high-pressure refrigerant working medium from the high-pressure compressor 12. The second throttling member 17 is used to throttle down the high-temperature and high-pressure refrigerant working medium after being secondarily compressed by the high-pressure compressor 12. The first throttling member 14 and the second throttling member 17 are commonly connected to the inlet of the low-temperature evaporator 15, throttling down the liquid refrigerants from the high-temperature condenser 11 and the condensation generator 7 into refrigerant working media with the same pressure respectively, and finally entering the low-temperature evaporator 15 to absorb the condensation heat of the water vapor of the low-temperature condenser 2.

[0037] In this embodiment, the first throttling member 14, the second throttling member 17, and the solution throttling member 8 can be any one or several of capillary tubes, thermostatic expansion valves, or electronic expansion valves; the air source evaporator 16 is a finned tube heat exchanger.

[0038] In this embodiment, the internal spaces of the low-temperature generator 1, the low-temperature condenser 2, the high-temperature evaporator 4, and the high-temperature absorber 5 form a sealed environment, which is usually maintained in a negative pressure state, and no non-condensable gases such as air are allowed to enter the internal space. Among them, the working pressures of the high-temperature evaporator 4 and the high-temperature absorber 5 are higher than those of the low-temperature condenser 2 and the low-temperature generator 1.

[0039] It should be noted that Figure 1 the direction shown by the arrow is the positive direction of the fluid flow. The salt solution used in the system is lithium bromide aqueous solution, lithium chloride aqueous solution, or calcium chloride aqueous solution, but is not limited to the above salt solutions. The working medium of the compression heat pump unit can use medium and low-temperature refrigerants such as R290 and R236fa, but is not limited to the above types of refrigerants.

[0040] Specifically, the working fluid regenerator 13 includes a liquid channel and a gas channel for heat exchange; the low-temperature evaporator 15 is placed inside the low-temperature condenser 2, the high-temperature condenser 11 is placed below the spray pipe Ⅰ 41 of the high-temperature evaporator 4, the outlet of the low-temperature evaporator 15 is connected to the gas channel inlet of the working fluid regenerator 13 through the air-source evaporator 16, the gas channel outlet of the working fluid regenerator 13 is connected to the inlet of the low-pressure compressor 10, and the outlet of the low-pressure compressor 10 is divided into two branches; the first branch is connected to the inlet of the high-temperature condenser 11, and the outlet of the high-temperature condenser 11 is connected to the liquid channel inlet of the working fluid regenerator 13; the liquid channel outlet of the working fluid regenerator 13 is connected to the inlet of the low-temperature evaporator 15 through the first throttling component 14; the second branch of the low-pressure compressor 10 is connected to the inlet of the high-pressure compressor 12, the outlet of the high-pressure compressor 12 is connected to the refrigerant channel inlet of the condensation generator 7, the refrigerant channel outlet of the condensation generator 7 is connected to the inlet of the low-temperature evaporator 15 through the second throttling component 17, the high-temperature condenser 11 is located below the spray part Ⅰ 41 in the high-temperature evaporator 4, and the low-temperature evaporator 15 is located in the internal space of the low-temperature condenser 2. Preferably, the low-temperature evaporator 15 is located in the lower part of the internal space of the low-temperature condenser 2.

[0041] The present invention also provides a heating method for a condensation heat recovery type high-temperature absorption heat pump system, including the following steps: The refrigerant working fluid of the compression type heat pump unit sequentially passes through the steam heat of the recovery absorption type heat pump unit and absorbs the heat energy of the external air to form low-temperature and low-pressure steam, and then compresses the low-temperature and low-pressure steam into superheated refrigerant steam. The superheated refrigerant steam is divided into two paths. One path of the refrigerant steam passes through the high-temperature condenser 11 to provide the latent heat of vaporization required for the water evaporation in the high-temperature evaporator 4; the other path of the refrigerant steam is further compressed into high-temperature and high-pressure superheated refrigerant steam, and the high-temperature and high-pressure superheated refrigerant steam exchanges heat with the dilute solution in the high-temperature absorber 5. The refrigerant working fluid passing through the high-temperature condenser 11 and the liquid refrigerant in the condensation generator 7 are throttled and depressurized to the refrigerant working fluid of the same pressure, and then enter the low-temperature evaporator 15 to exchange heat with the water vapor in the low-temperature condenser 2.

[0042] Specifically, the refrigerant working medium of the compression heat pump unit sequentially passes through the low-temperature evaporator 15 to recover the condensation heat of the water vapor of the absorption heat pump unit, and the air-source evaporator 16 to absorb the heat energy of the external ambient air and become a low-temperature and low-pressure steam. It is first compressed by the low-pressure compressor 10 to become a superheated refrigerant steam with a higher temperature and higher pressure, thus completing the first-stage compression process. The superheated refrigerant steam with a higher temperature discharged from the low-pressure compressor 10 needs to achieve two functions. Part of the refrigerant steam enters the high-temperature condenser 11 to provide the latent heat of vaporization required for the water evaporation in the high-temperature evaporator 4, while the other part of the refrigerant steam is compressed by the high-pressure compressor 12 to become a superheated refrigerant steam with a high temperature and high pressure, thus completing the second-stage compression process, thereby realizing the staged compression process of the refrigerant steam. The superheated refrigerant steam with a high temperature and high pressure enters the condensation generator 7 to provide part of the heating amount required for the further concentration of the dilute solution from the high-temperature absorber 5. Finally, the liquid refrigerants of the high-temperature condenser 11 and the condensation generator 7 respectively pass through the first throttling component 14 and the second throttling component 17 connected in parallel to become refrigerant working media with the same pressure, and enter the low-temperature evaporator 15 to absorb the condensation heat of the refrigerant water vapor in the low-temperature condenser 2.

[0043] The concentrated salt solution in the low-temperature generator 1 of the absorption heat pump unit is pumped to the high-temperature absorber 5 for heat exchange to realize external heat supply. The concentrated salt solution is mixed with the steam provided by the high-temperature evaporator 4 to form a dilute salt solution, and then passes through the solution heat exchanger 6 for heat exchange with the concentrated salt solution from the low-temperature generator 1. Then, the discharged concentrated salt solution undergoes a cascade heating process to generate water vapor and enters the low-temperature condenser 2 for heat exchange with the compression heat pump unit.

[0044] Specifically, the concentrated solution in the low-temperature generator 1 of the absorption heat pump unit is pressurized by the pump II 9 and sent to the high-temperature absorber 5 to absorb the heat released by the water vapor absorption to produce hot water for building heating or industrial heating. The concentrated salt solution in the high-temperature absorber 5 absorbs the water vapor and becomes a dilute salt solution. Then, after preheating the concentrated salt solution from the low-temperature generator 1 through the solution heat exchanger 6, it sequentially enters the condensation generator 7 and the low-temperature generator 1, and is heated by the condensation heat of the refrigerant steam of the compression heat pump unit and the external heat source to realize the cascade heating process of the dilute salt solution. The water vapor generated by the low-temperature generator 1 enters the low-temperature condenser 2 and is recovered by the compression heat pump unit to produce high-temperature heat energy, so as to provide the latent heat of vaporization required for the water evaporation in the high-temperature evaporator 4 and the heating amount required for the solution generation in the condensation generator 7. The liquid refrigerant water in the low-temperature condenser 2 is pressurized by the pump I 3 and sent to the high-temperature evaporator 4 to absorb heat and vaporize, and then enters the high-temperature absorber 5 to be absorbed by the concentrated solution, thereby producing high-temperature hot water for building heating or industrial heating.

[0045] In this solution, the system produces high-temperature thermal energy through the staged compression process of the refrigerant working medium and the cascaded generation process of the dilute salt solution, so as to provide recommended heating or industrial heating, and is used to recover the condensation heat of the heat pump unit and utilize the air thermal energy in the high-temperature environment. The dual-temperature thermal energy is controlled through multi-stage compression and the utilization of air energy. The dual-temperature thermal energy is produced through the staged compression process to provide the heating amount required by the high-temperature evaporator 4 and part of the heating amount required for solution generation. The dilute salt solution first absorbs the condensation heat of the compression heat pump unit through the condensation generator 7, and then absorbs the heating amount of the external heat source through the low-temperature generator 1, so as to realize the cascaded heating and generation process of the dilute salt solution. By recovering the condensation heat of the traditional absorption heat pump and the air thermal energy in the high-temperature environment, the purpose of significantly reducing the heating amount obtained by the system from the outside is achieved. This solution effectively solves the problem of low efficiency existing in the traditional temperature-rising absorption heat pump.

[0046] As described above, it is only the preferred embodiment of the present invention, and it does not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can make some changes or modifications to the equivalent embodiments by using the disclosed technical content within the scope of the technical solution of the present invention. However, as long as it does not depart from the content of the technical solution of the present invention, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A condensation heat recovery type high temperature absorption heat pump system, characterized in that: It includes an absorption heat pump unit and a compression heat pump unit; the absorption heat pump unit includes a low-temperature generator, a low-temperature condenser, a high-temperature evaporator, a high-temperature absorber and a condensation generator; the steam outlet of the low-temperature generator is connected to the inlet of the low-temperature condenser, the outlet of the low-temperature condenser is connected to the inlet of the high-temperature evaporator through pump I, and the steam outlet of the high-temperature evaporator is connected to the steam inlet of the high-temperature absorber; a high-temperature condenser is arranged in the internal space of the high-temperature evaporator, and the high-temperature condenser is connected to the refrigerant channel of the compression heat pump unit; the condensation generator includes a solution channel and a refrigerant channel for realizing heat exchange, and the refrigerant channel of the condensation generator is connected to the refrigerant channel of the compression heat pump unit; the solution inlet of the high-temperature absorber is connected to the solution outlet of the low-temperature generator; the solution outlet of the high-temperature absorber is connected to the solution channel inlet of the condensation generator; the compression heat pump unit is used to absorb air heat energy and steam condensation heat of the absorption heat pump unit, and to produce high-temperature potential heat energy to provide the latent heat of vaporization required for water evaporation in the high-temperature evaporator and the solution generation heat required by the condensation generator.

2. A condensation heat recovery type high temperature absorption heat pump system according to claim 1, characterized in that: The absorption heat pump unit also includes a solution heat exchanger, which includes a dilute solution channel and a concentrated solution channel for achieving heat exchange, the dilute solution channel inlet of the solution heat exchanger is connected to the solution outlet of the high-temperature absorber, the dilute solution channel outlet of the solution heat exchanger is connected to the solution channel inlet of the condensation generator via a solution throttling component, and the solution channel outlet of the condensation generator is connected to the solution inlet of the low-temperature generator; the concentrated solution channel inlet of the solution heat exchanger is connected to the solution outlet of the low-temperature generator via pump II, and the concentrated solution channel outlet of the solution heat exchanger is connected to the solution inlet of the high-temperature absorber.

3. A condensation heat recovery type high temperature absorption heat pump system according to claim 1, characterized in that: The compression heat pump unit includes a low-temperature evaporator, an air source evaporator, a working medium heat regenerator, a low-pressure compressor, a high-temperature condenser, a high-pressure compressor and a condensation generator; The working fluid heat exchanger includes a liquid channel and a gas channel for heat exchange; the low-temperature evaporator is placed inside the low-temperature condenser, and the high-temperature condenser is placed below the inlet of the high-temperature evaporator; the outlet of the low-temperature evaporator is connected to the gas channel inlet of the working fluid heat exchanger through the air source evaporator, and the gas channel outlet of the working fluid heat exchanger is connected to the inlet of the low-pressure compressor, and the outlet of the low-pressure compressor is divided into two branches; the first branch is connected to the inlet of the high-temperature condenser, and the outlet of the high-temperature condenser is connected to the liquid channel inlet of the working fluid heat exchanger; the liquid channel outlet of the working fluid heat exchanger is connected to the inlet of the low-temperature evaporator through the first throttling component; the second branch is connected to the inlet of the high-pressure compressor, and the outlet of the high-pressure compressor is connected to the refrigerant channel inlet of the condensation generator, and the refrigerant channel outlet of the condensation generator is connected to the solution inlet of the low-temperature evaporator through the second throttling component.

4. A condensation heat recovery type high temperature absorption heat pump system according to claim 1, characterized in that: The inlet of the high-temperature evaporator is provided with a spray component I, and the spray component I is located in the inner space of the high-temperature evaporator and is arranged above the high-temperature condenser.

5. A condensation heat recovery type high temperature absorption heat pump system according to claim 1, characterized in that: A heater is provided inside the low temperature generator for providing heating from an external heat source.

6. A condensation heat recovery type high temperature absorption heat pump system according to claim 1, characterized in that: A heat exchanger is arranged in the high-temperature absorber, a spraying part II is arranged at the inlet of the dilute solution of the high-temperature absorber, and the heat exchanger is located below the spraying part II.

7. A condensation heat recovery type high temperature absorption heat pump system according to claim 3, characterized in that: The solution heat exchanger, condensation generator and working medium heat regenerator are any one or more of plate heat exchangers, shell-and-tube heat exchangers or shell-and-tube heat exchangers.

8. A condensation heat recovery type high temperature absorption heat pump system according to claim 3, characterized in that: The air source evaporator is a fin-tube heat exchanger.

9. A heating method of a condensation heat recovery type high temperature absorption heat pump system, characterized in that: The steps include: The refrigerant working medium of the compression heat pump unit successively recovers the steam heat of the absorption heat pump unit and absorbs the heat energy of the external air to form low-temperature and low-pressure steam, and then compresses the low-temperature and low-pressure steam into superheated refrigerant steam, and the superheated refrigerant steam is divided into two paths, one of which is the refrigerant steam that passes through the high-temperature condenser to provide the latent heat of vaporization required for the evaporation of water in the high-temperature evaporator; the other refrigerant steam is further compressed to become high-temperature and high-pressure superheated refrigerant steam, and the high-temperature and high-pressure superheated refrigerant steam exchanges heat with the dilute solution from the high-temperature absorber, and the liquid refrigerant passing through the high-temperature condenser and the liquid refrigerant in the condensation generator become refrigerant working medium of the same pressure after passing through the throttling component, and then enters the low-temperature evaporator to exchange heat with the water vapor in the low-temperature condenser.

10. The heating method of the condensation heat recovery type high temperature absorption heat pump system according to claim 9, characterized in that: The concentrated solution in the low-temperature generator of the absorption heat pump unit is sent to the high-temperature absorber through pump II for heat exchange to achieve external heating. The concentrated solution absorbs the water vapor provided by the high-temperature evaporator to form a dilute solution, and then passes through the solution heat exchanger to exchange heat with the concentrated solution from the low-temperature generator. The discharged dilute solution then undergoes a step heating process to generate water vapor and enters the low-temperature condenser to exchange heat with the compression heat pump unit, and finally forms liquid water and is sent to the high-temperature evaporator through pump I.

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