CN113883741A

CN113883741A - Absorption refrigeration system

Info

Publication number: CN113883741A
Application number: CN202111199267.4A
Authority: CN
Inventors: 盛凯; 石靖峰; 陈见兴; 矫晓龙
Original assignee: Qingdao Hisense Hitachi Air Conditioning System Co Ltd
Current assignee: Qingdao Hisense Hitachi Air Conditioning System Co Ltd
Priority date: 2021-10-14
Filing date: 2021-10-14
Publication date: 2022-01-04
Anticipated expiration: 2041-10-14
Also published as: CN113883741B

Abstract

The invention discloses an absorption refrigeration system, which comprises a generator, a condenser, a throttling component, an evaporator, a first injection type heat insulation absorber, a second injection type heat insulation absorber, a cooler, an exchanger, a first solution pump and a second solution pump, wherein the generator is connected with the first injection type heat insulation absorber; the generator is also connected with a heat collector, working fluid in the generator is heated and boiled by the heat collector and then is conveyed into the generator, the expansion work of high-temperature and high-pressure solution is recovered by utilizing the heat insulation absorption refrigeration mode of the double ejectors, the heat transfer medium in the absorption process is strengthened in a segmented manner, the absorption pressure is increased, the solution absorption effect is enhanced, the stepped segmented absorption of concentrated solution is realized, and the purposes of saving high-grade electric energy, reducing the unit volume, improving the refrigeration efficiency and expanding the applicable temperature area of the air-cooled absorption refrigeration cycle are achieved; the generator is externally connected with the heat collector, and the solar energy absorbed by the heat collector, the waste heat energy of a factory or the heat energy of an underground water source are absorbed and utilized, so that the energy utilization rate is effectively improved, and the sustainable development is facilitated.

Description

Absorption refrigeration system

Technical Field

The invention belongs to the technical field of air conditioners, and particularly relates to an absorption refrigeration system.

Background

A refrigeration system refers to any system that uses external energy to transfer heat from a substance or environment at a low temperature to a substance or environment at a higher temperature. Generally, the refrigerant undergoes four processes of compression, condensation, expansion and evaporation, forms the most basic configuration of a refrigeration cycle, and can be classified into a compression refrigeration system, an absorption refrigeration system, a vapor-injection refrigeration system and the like according to the device form.

Absorption refrigeration is a refrigeration technology which consumes heat energy, depends on vaporization and heat absorption of a liquid refrigerant in an evaporator, and forces the heat to be continuously transferred from low temperature to high temperature, is one of common refrigeration methods, adopts a binary solution formed by two substances with different boiling points and capable of being mutually dissolved as a working medium (a high boiling point substance is used as an absorbent, and a low boiling point substance is used as a refrigerant), and utilizes the characteristic that the saturated concentration of the solution changes along with temperature and pressure to carry out refrigeration circulation.

Compared with a compression type refrigeration technology, the absorption type refrigeration technology has the advantages of low mechanical energy consumption, direct refrigeration by utilizing heat energy, few moving parts, low noise and the like, and meanwhile, salt solutions such as LiBr/H20 or H2O are often used as working media, so that the absorption type refrigeration technology is energy-saving and environment-friendly and is one of better refrigeration modes for replacing the compression type refrigeration technology.

The absorption type refrigerating machine is divided into a water cooling mode and an air cooling mode from the aspect of a cooling mode, the COP of the water cooling type absorption refrigerating machine is higher than that of the air cooling type absorption refrigerating machine, however, the air cooling type absorption refrigerating machine has the advantages of cleanness, environmental protection, safety, sanitation, water resource saving, convenience and quickness in installation, wide application range and the like, but the problems of high generation temperature, overlarge solution circulation multiplying power, small refrigeration temperature area and overlarge unit volume exist in the working process of the existing air cooling type single-effect absorption type circulation, so that the utilization rate of an absorption type refrigerating agent to energy in the specific working process is insufficient, and heat loss exists.

Patent document CN 103423912A discloses a small air-cooled absorption refrigerator, which comprises a generator, an air-cooled condenser, a throttle valve, an evaporator, an absorber, a first solution pump, an air-cooled precooler, a mixer, a solution heat exchanger and a flow divider, and is characterized in that a non-heat-insulated absorber, an air-cooled precooler and a flow divider are adopted, so that the refrigeration performance of the system is improved; but the heat and mass transfer area required by the system is increased, the volume is increased, and the refrigeration performance and the adaptive temperature area of the system are still to be improved.

Disclosure of Invention

The invention aims to provide an absorption refrigeration system, which solves the problems of high generation temperature, overlarge solution circulation multiplying power, overlarge system refrigeration efficiency and the like in the working process of the existing air-cooled single-effect absorption type circulation in the prior art.

In order to realize the purpose of the invention, the invention is realized by adopting the following technical scheme:

an absorption refrigeration system, comprising:

the system comprises a generator, a condenser, a throttling part, an evaporator, a first jet type heat-insulating absorber, a second jet type heat-insulating absorber, a cooler, an exchanger, a first solution pump and a second solution pump;

a solution outlet of the generator is connected with a working fluid inlet of the first jet type heat-insulating absorber, an outlet of the first jet type heat-insulating absorber is connected with an inlet of the second solution pump, an outlet of the second solution pump is connected with an inlet of the cooler, an outlet of the cooler is connected with a working fluid inlet of the second jet type heat-insulating absorber, an outlet of the second jet type heat-insulating absorber is divided into two paths, one path of the outlet is connected with the solution inlet of the generator through the second solution pump, and the other path of the outlet and the outlet of the first jet type heat-insulating absorber are connected with an inlet of the second solution pump;

and a steam outlet of the generator is respectively connected with a steam inlet of the first jet type heat-insulating absorber and a steam inlet of the second jet type heat-insulating absorber after passing through the condenser, the throttling part and the evaporator.

In some embodiments of the present application, a regulating valve is provided in series on the pipeline between the outlet of the second ejector adiabatic absorber and the inlet of the second solution pump.

In some embodiments of the present application, a circulating water outlet and a circulating water inlet are further formed in the generator, and circulating water is output from the circulating water outlet, enters the heat collector through the circulating water pump, is heated and boiled by the heat collector, and is then conveyed back to the generator through the circulating water inlet.

In some embodiments of the present application, a working fluid line between the solution outlet of the generator and the working fluid inlet of the first ejector adiabatic absorber exchanges heat with a working fluid line between the outlet of the first solution pump and the solution inlet of the generator through a solution heat exchanger.

In some embodiments of the present application, the first and second thermal isolators each include a mixing absorption chamber, a constant pressure absorption chamber, and a diffusion absorption chamber.

In some embodiments of the present application, the throttling component is a thermal expansion valve, a capillary valve, or an electronic expansion valve.

In some embodiments of the present application, the heat collector energy is derived from one or more of solar energy, plant waste heat energy, and ground water source heat energy.

In some embodiments of the present application, the solution heat exchanger is a plate heat exchanger, a double pipe heat exchanger, or a shell and tube heat exchanger.

In some embodiments of the present application, the evaporator is a plate heat exchanger, a double pipe heat exchanger, or a shell and tube heat exchanger.

In some embodiments of the present application, the condenser is an air-cooled condenser, the cooler is an air-cooled cooler, and the condenser and the cooler are finned heat exchangers.

Compared with the prior art, the invention has the advantages and positive effects that:

the absorption refrigeration system that this application is related to is provided with first injection formula adiabatic absorber and the adiabatic absorber of second injection formula, utilizes the adiabatic absorption refrigeration mode of two ejectors, retrieves the work of expansion of high temperature high pressure solution, strengthens the heat transfer medium segmentation of absorption process, increases the absorption pressure, and the reinforcing solution absorbs the effect, realizes the ladder level segmentation of concentrated solution and absorbs.

The generator is externally connected with the heat collector, and the solar energy absorbed by the heat collector, the waste heat energy of a factory or the heat energy of an underground water source are absorbed and utilized, so that the energy utilization rate is effectively improved, and the sustainable development is facilitated.

Other features and advantages of the present invention will become more apparent from the following detailed description of the invention when taken in conjunction with the accompanying drawings.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic structural diagram of an embodiment of an absorption refrigeration system in accordance with the present invention;

FIG. 2 is a schematic view of a first or second thermal ejector;

in the figure, the position of the upper end of the main shaft,

10. a generator;

11. a heat collector;

12. a water circulating pump;

20. a condenser;

30. a throttling member;

40. an evaporator;

51. a first ejector adiabatic absorber;

52. a second ejector adiabatic absorber;

501. a mixing and absorbing chamber;

502. a constant pressure absorption chamber;

503. a diffusion absorption chamber;

60. a cooler;

71. a first solution pump;

72. a second solution pump;

80. adjusting a valve;

90. a solution heat exchanger.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In the description of the present application, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a particular orientation, be constructed in a particular orientation, and be operated, and thus should not be construed as limiting the present application.

The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless otherwise specified.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; may be mechanically coupled, may be directly coupled, or may be indirectly coupled through an intermediary. The specific meaning of the above terms in the present application can be understood in a specific case by those of ordinary skill in the art.

In the present invention, unless otherwise expressly stated or limited, "above" or "below" a first feature means that the first and second features are in direct contact, or that the first and second features are not in direct contact but are in contact with each other via another feature therebetween. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

The following disclosure provides many different embodiments or examples for implementing different features of the invention. To simplify the disclosure of the present invention, the components and arrangements of specific examples are described below. Of course, they are merely examples and are not intended to limit the present invention. Furthermore, the present invention may repeat reference numerals and/or letters in the various examples, such repetition is for the purpose of simplicity and clarity and does not in itself dictate a relationship between the various embodiments and/or configurations discussed.

The air-cooled cooler and the heat-insulating absorber are adopted to replace an air-cooled in-tube falling film absorber in the traditional air-cooled absorption refrigerator, so that the problems of large volume and low energy efficiency of the air-cooled absorption refrigerator can be effectively solved.

The absorption and mass transfer processes are carried out in the heat insulation absorber, the heat transfer process is carried out in the air-cooled cooler, and the heat and mass transfer processes are strengthened in stages, so that the refrigeration efficiency of the traditional air-cooled absorption refrigerator can be effectively improved, and the unit volume is reduced; however, as the temperature is reduced and the ambient temperature is increased, the unit refrigeration efficiency is rapidly reduced to failure, and the refrigeration temperature, the refrigeration efficiency and the adaptive temperature zone of the air-cooled adiabatic absorption refrigerator still need to be broken through.

As shown in fig. 1, the present application proposes an absorption refrigeration system including a generator 10, a condenser 20, a throttling part 30, an evaporator 40, a first ejector adiabatic absorber 51, a second ejector adiabatic absorber 52, a cooler 60, a solution heat exchanger 90, a first solution pump 71, and a second solution pump 72; the generator 10 is externally connected with a heat collector 11 and a circulating water pump 12, and the heat collector 11 is used for heating and boiling the low-temperature dilute solution in the generator 10 to generate high-temperature and high-pressure concentrated solution.

Specifically, the generator 10 is further provided with a circulating water outlet and a circulating water inlet, and circulating water is output from the circulating water outlet, enters the heat collector 11 through the circulating water pump 12, is heated and boiled by the heat collector 11, and is then conveyed back to the generator 10 from the circulating water inlet.

The solution outlet of the generator 10 is connected to the working fluid inlet of the first ejector adiabatic absorber 51, the outlet of the first ejector adiabatic absorber 51 is connected to the inlet of the second solution pump 72,

the outlet of the second solution pump 72 is connected to the inlet of the cooler 60, the outlet of the cooler 60 is connected to the working fluid inlet of the second ejector thermal-insulation absorber 52, the outlet of the second ejector thermal-insulation absorber 52 is divided into two paths, one path is connected to the solution inlet of the generator 10 through the first solution pump 71, and the other path is connected to the inlet of the second solution pump 72 together with the outlet of the first ejector thermal-insulation absorber 51.

The working medium pipeline between the solution outlet of the generator 10 and the working fluid inlet of the first jet type heat-insulating absorber 51 exchanges heat with the working medium pipeline between the outlet of the first solution pump 71 and the solution inlet of the generator 10 through the solution heat exchanger 90.

A regulating valve 80 is provided in series on a pipe between the outlet of the second ejector thermal insulation absorber 52 and the inlet of the second solution pump 72, for regulating the flow rate ratio between the two flow paths outputted from the second ejector thermal insulation absorber 52.

The specific flow process of the working fluid and the steam is as follows: the high-temperature and high-pressure concentrated solution generated after the generator 10 is heated and boiled by the heat collector 11 is output from the solution outlet of the generator 10, and exchanges heat with the low-temperature dilute solution from the first solution pump 71 in the solution heat exchanger 90.

The concentrated solution with heat release and temperature reduction is used as working fluid and enters the first injection type heat insulation absorber 51 from a working fluid inlet of the first injection type heat insulation absorber 51, the working fluid injects the saturated steam output by the evaporator 40 in the flowing process of the working fluid in the first injection type heat insulation absorber 51, the solution and the steam are fully mixed in the first injection type heat insulation absorber 51, and the pressurizing efficiency enhancement and the heat insulation absorption processes are sequentially completed to generate saturated solution.

The saturated solution output by the first jet type heat insulation absorber 51 is fully mixed with the recycled solution output by the second jet type heat insulation absorber 52, the mixed solution enters a second solution pump 72 to be pressurized, then enters the air-cooled cooler 60 to release heat and cool, then enters the second jet type heat insulation absorber 52 as working fluid, the injection evaporator 40 outputs saturated steam to the second jet type heat insulation absorber 52, the solution and the steam are fully mixed in the second jet type heat insulation absorber 52 to complete the pressurizing efficiency enhancement and the heat insulation absorption processes in sequence, and saturated solution is generated.

The saturated solution output by the second spray type heat insulation absorber 52 is divided into two paths, one path enters the first solution pump 71 to be pressurized, and then enters the solution heat exchanger 90 to exchange heat with the high-temperature high-pressure concentrated solution at the outlet of the generator 10, the diluted solution with heat absorption and temperature rise enters the generator 10 to be reheated and boiled by the solar heat collection subsystem, and the other path is mixed with the saturated solution output by the first spray type heat insulation absorber 51 and then enters the second solution pump 72 to be pressurized.

The generator 10 outputs high-temperature and high-pressure refrigerant vapor, the refrigerant vapor enters the condenser 20 to exchange heat with the external environment, saturated liquid after heat release and condensation enters the throttling part 30, and the saturated liquid is subjected to adiabatic throttling in the throttling part 30 to be refrigerant wet vapor under evaporation pressure.

The wet steam enters the evaporator 40 to exchange heat with refrigerant water, and the evaporation absorbs heat to form saturated steam. Saturated steam at the outlet of the evaporator 40 is divided into two paths, and the two paths of saturated steam are used as injection fluid and respectively enter the first injection type heat-insulation absorber 51 and the second injection type heat-insulation absorber 52 to finish the processes of pressurization and efficiency enhancement and heat-insulation absorption, and are subjected to heat-insulation absorption by the solution.

The high-temperature high-pressure concentrated solution at the outlet of the generator 10 is subcooled by the solution heat exchanger 90 and enters the first jet type heat-insulating absorber 51 as working fluid to inject the saturated steam output by the evaporator 40, so that the first heat-insulating absorption process of the solution is completed.

The saturated solution at the outlet of the first jet type heat-insulating absorber 51 is fully mixed with the recycled solution at the outlet of the second jet type heat-insulating absorber 52, is pressurized by a second solution pump 72, then enters the air-cooled cooler 60 for cooling, and enters the second jet type heat-insulating absorber 52 as a working fluid to inject the saturated steam at the outlet of the evaporator 40, so that the second heat-insulating absorption process of the solution is completed, and the stepped and segmented absorption of the solution is realized.

The generator 10, the solution heat exchanger 90, the first injection type heat-insulation absorber 51, the second solution pump 72, the cooler 60, the second injection type heat-insulation absorber 52 and the first solution pump 71 are sequentially connected in series; the generator 10, the condenser 20, the throttling part 30 and the evaporator 40 are connected in series in sequence.

The saturated refrigerant vapor generated by the evaporator 40 is divided into two paths, and both paths are used as injection fluids, and respectively enter the first injection type heat-insulation absorber 51 and the second injection type heat-insulation absorber 52 to be fully absorbed by the solution.

The first injection type heat-insulating absorber 51 and the second injection type heat-insulating absorber 52 are designed by integrating an injector and a heat-insulating absorber, and can respectively realize the pressurization and synergy of the injection fluid and the heat-insulating absorption process of the working fluid.

As shown in fig. 2, each of the first and second ejector type

thermal isolators

51 and 52 includes a mixing absorption chamber 501, a constant pressure absorption chamber 502, and a diffusion absorption chamber 503, the mixing absorption chamber 501 is used for mixing the working fluid input from the working fluid inlet and the saturated steam input from the steam inlet, and the mixed fluid passes through the constant pressure absorption chamber 502 and the diffusion absorption chamber 503 to complete the pressurization and heat insulation absorption processes, form a saturated solution, and is conveyed forward.

The throttle unit 30 is any one of a thermostatic expansion valve, a capillary valve, or an electronic expansion valve.

The heat source of the solar heat collecting subsystem is mainly solar energy, and can also be energy in one or a plurality of mixed forms of waste heat generated by factories, underground water source heat energy and the like.

The heat exchangers such as the solution heat exchanger 90 and the evaporator 40 are plate heat exchangers, double pipe heat exchangers or shell-and-tube heat exchangers.

The working medium of the solar heat collecting subsystem is water or industrial waste heat; the working medium of the absorption-injection composite circulation subsystem is LiBr/H2O.

The condenser 20 is an air-cooled condenser 20, the cooler 60 is an air-cooled cooler 60, and both the condenser 20 and the cooler 60 are fin heat exchangers.

The absorption refrigeration system related to the application utilizes the adiabatic absorption refrigeration mode with the double ejectors to recover the expansion work of high-temperature and high-pressure solution, strengthens the heat and mass transfer subsection of the absorption process, increases the absorption pressure, enhances the absorption effect, realizes the gradient subsection absorption of concentrated solution, solves the problems of higher generation temperature, overlarge solution circulation multiplying power, overlow system refrigeration efficiency, smaller refrigeration temperature area and overlarge unit volume of the traditional air-cooled single-effect absorption type circulation, achieves the purposes of saving high-grade electric energy, reducing the unit volume, improving the refrigeration efficiency, expanding the applicable temperature area of the air-cooled absorption refrigeration circulation, and meets the requirements for low-temperature cold water in life or production.

In the foregoing description of embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The above embodiments are only specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention are included in the scope of the present invention, and therefore, the scope of the present invention shall be subject to the claims.

Claims

1. An absorption refrigeration system, comprising:

a solution outlet of the generator is connected with a working fluid inlet of the first jet type heat-insulating absorber, an outlet of the first jet type heat-insulating absorber is connected with an inlet of the second solution pump, an outlet of the second solution pump is connected with an inlet of the cooler, an outlet of the cooler is connected with a working fluid inlet of the second jet type heat-insulating absorber, an outlet of the second jet type heat-insulating absorber is divided into two paths, one path of the outlet is connected with the solution inlet of the generator through the first solution pump, and the other path of the outlet and the outlet of the first jet type heat-insulating absorber are connected with an inlet of the second solution pump;

2. An absorption refrigeration system according to claim 1,

and a regulating valve is connected in series on a pipeline between the outlet of the second jet type heat insulation absorber and the inlet of the second solution pump.

3. An absorption refrigeration system according to claim 1,

and a circulating water outlet and a circulating water inlet are formed in the generator, circulating water is output from the circulating water outlet, enters the heat collector through the circulating water pump, is heated and boiled by the heat collector, and is conveyed back to the generator from the circulating water inlet.

4. An absorption refrigeration system according to claim 1,

and a working medium pipeline between a solution outlet of the generator and a working fluid inlet of the first jet type heat insulation absorber exchanges heat with a working medium pipeline between an outlet of the first solution pump and a solution inlet of the generator through a solution heat exchanger.

5. An absorption refrigeration system according to claim 1,

the first and second thermal isolators each include a mixing absorption chamber, a constant pressure absorption chamber, and a diffusion absorption chamber.

6. An absorption refrigeration system according to claim 1,

the throttling component is a thermal expansion valve, a capillary valve or an electronic expansion valve.

7. An absorption refrigeration system according to claim 3,

the energy of the heat collector is derived from one or more of solar energy, factory waste heat energy and underground water source heat energy.

8. An absorption refrigeration system according to claim 4,

the solution heat exchanger is a plate heat exchanger, a double-pipe heat exchanger or a shell-and-tube heat exchanger.

9. An absorption refrigeration system according to claim 1,

the evaporator is a plate heat exchanger, a double-pipe heat exchanger or a shell-and-tube heat exchanger.

10. An absorption refrigeration system according to claim 1,

the condenser is an air-cooled condenser, the cooler is an air-cooled cooler, and the condenser and the cooler are fin type heat exchangers.