CN107816821B

CN107816821B - Solar adsorption and absorption cascade refrigeration and heating system

Info

Publication number: CN107816821B
Application number: CN201610820795.XA
Authority: CN
Inventors: 李志永; 李姗姗; 代云; 郁文红
Original assignee: North China University of Technology
Current assignee: North China University of Technology
Priority date: 2016-09-14
Filing date: 2016-09-14
Publication date: 2020-01-07
Anticipated expiration: 2036-09-14
Also published as: CN107816821A

Abstract

The invention provides a solar energy adsorption and absorption cascade refrigeration and heating system, which utilizes a photo-thermal and photo-cold solar energy conversion device to collect solar heat energy to provide heat for a generator in the daytime and desorb adsorbates and an adsorbent in the device, wherein the adsorbent in the device absorbs the adsorbates at night, the adsorption heat generated in the adsorption process can provide heat for the night operation of the generator, and meanwhile, cold energy is generated in the liquid evaporation process of the adsorbates and can cool a condenser and an absorber. The photo-thermal and photo-cold solar energy conversion device comprises a shell, a closed cavity, a condenser, an inner pipeline, an adsorbent, a liquid collection cavity, a wall surface and the like. The wall surface and the condenser form a closed liquid collecting cavity, the inner pipeline penetrates through the center of the liquid collecting cavity, a closed cavity is formed between the wall surface and the shell and is communicated with the outside through a pipeline, and an adsorbent is fixed on the outer surface of the inner pipeline. The device realizes two-stage utilization of solar refrigeration and heating, realizes night operation of the absorption refrigeration system in a mode without an auxiliary heat source, and improves the utilization rate of solar energy.

Description

Solar adsorption and absorption cascade refrigeration and heating system

Technical Field

The invention relates to the field of solar refrigeration and heating, in particular to a solar adsorption and absorption cascade refrigeration and heating system.

Background

The solar refrigeration system mainly has two modes of absorption refrigeration and adsorption refrigeration. In the absorption refrigeration system, because of the shortage of solar heat energy at night, an auxiliary heat source is often needed for heating, and the efficiency of the refrigeration system is reduced. In the adsorption type refrigerating system, because of the limitation of the principle, continuous circulation refrigeration cannot be performed, and the adsorption type refrigerating system can only be used at night to provide refrigerating capacity, so that the application occasions are limited. In order to solve the problem, the invention combines absorption refrigeration and adsorption refrigeration, and provides a solar adsorption and absorption cascade refrigeration and heating system, and the core component of the system is a photo-thermal and photo-cooling solar energy conversion device. The device collects solar heat energy daytime and provides the heat for the generator simultaneously, desorbs adsorbate and adsorbent in the device, and at night, the adsorbate is absorbed to the adsorbent in the device, and the adsorption heat that the adsorption process produced can provide the heat for the night operation of generator, produces cold volume in the adsorbate liquid evaporation process simultaneously, and this cold volume can be for condenser and absorber cooling. Therefore, the system not only solves the problem of auxiliary heating of the absorption refrigeration system at night, but also realizes continuous supply of cold energy, and can provide heat energy for users, improve the refrigeration efficiency and the utilization rate of solar energy, and expand the application occasions of the solar refrigeration system.

Disclosure of Invention

Based on the problems in the prior art, the invention provides a solar energy adsorption and absorption cascade refrigeration and heating system in an innovative way. The system not only reduces the application of the auxiliary heat source at night, but also can realize the continuous supply of cold and heat to users. The system has the core components of a photo-thermal and photo-cold solar energy conversion device, and the device heats working media in the closed cavity in the daytime through a collecting lens on the surface and an adsorbent on the periphery of the pipeline, cools the working media in the closed cavity at night and heats the working media in the pipeline at the same time. The solar adsorption and absorption cascade refrigeration and heating system provided by the invention reduces the use of auxiliary heat sources, reduces the environmental pollution, improves the refrigeration efficiency and the solar utilization rate, and realizes the purposes of energy conservation and environmental protection.

The technical scheme adopted by the invention for solving the technical problems is as follows:

solar energy adsorbs, absorbs step refrigeration and heating system, includes: the system comprises an evaporator 9, a condenser 10, an expansion valve 23, a generator 11, a solution heat exchanger 12, an absorber 13, a ground heat exchanger 14, a photo-thermal and photo-cold solar energy conversion device 15, valves and pipelines. Wherein light and heat, cold solar energy conversion equipment of light includes: the device comprises a shell 1, a closed cavity 2, a condenser 3, an inner pipeline 5, an adsorbent 6, a liquid collecting cavity 7 and a wall surface 8, wherein the wall surface 8 and the condenser 3 form the closed liquid collecting cavity 7, the inner pipeline 5 penetrates through the center line of the liquid collecting cavity 7, and the adsorbent 6 is fixed on the outer surface of the inner pipeline 5; the wall surface 8, the condenser 3, the inner pipeline 5 and the adsorbent 6 form a solar energy utilization unit which can refrigerate and heat; the units are arranged in an array and are communicated through an inner conduit 5. The wall 8 and the shell 1 in the array form a closed cavity 2, and the closed cavity 2 is communicated with the outside through a pipeline 36 and a pipeline 38.

Further, according to the solar energy adsorption and absorption cascade refrigeration and heating system, in the daytime, the solar rays 4 irradiate the condenser lens 3, the concentrated solar rays irradiate the adsorbent 6, the adsorbent 6 is heated, the adsorbent desorbs adsorbate vapor, the adsorbate vapor condenses into liquid on the inner surface of the wall surface 8 and releases latent heat, water on the outer side of the wall surface is heated, and the temperature of the working medium in the sealed cavity 2 is increased. During the operation of the daytime system, the

valves

17, 19, 22, 23, 24 are opened, the

valves

16, 18, 20, 21 are closed, the working medium in the closed cavity respectively flows through the valve 22, the heat exchange coil 44 in the generator 11, the pump 49, and the valve 17, finally returns to the closed cavity 2 in the photo-thermal and photo-cold solar energy conversion device 15 to complete the heating cycle, so as to achieve the purpose of heating the dilute solution in the generator 11, meanwhile, the high-temperature working medium flowing out from the heat exchange coil 43 of the condenser 10 respectively flows through the valve 19, the pipeline 32, the buried pipe heat exchanger 14, the heat exchange coil 46 in the absorber 13, and finally returns to the condenser 10 to complete the cycle, so as to achieve the purpose of cooling the working medium in the absorber 13 and the condenser 10.

Further, according to the solar energy adsorption and absorption cascade refrigeration and heating system, at night, no sunlight is irradiated, the temperature of the adsorbent 6 is reduced, the adsorbent adsorbs the adsorbate vapor, so that the pressure of the adsorbate vapor in the liquid collection cavity 7 is reduced, and the adsorbate liquid at the bottom of the liquid collection cavity is evaporated. The adsorbate evaporates to absorb heat, so that the temperature of the working medium on the outer side of the wall surface 8 is reduced; after the adsorbent absorbs the adsorbate vapor, the adsorbent releases the heat of adsorption, so that the temperature of the working medium in the inner pipeline 5 is increased. When the night system operates, the

valves

16, 18, 20, 21, 23, 24 are opened, the

valves

17, 19, 22 are closed, the high-temperature working medium flowing out of the heat exchange coil 43 of the condenser 10 flows into the sealed cavity 2 in the photo-thermal and photo-cooling solar energy conversion device 15 through the valve 18, flows out through the valve 21 after being cooled, then sequentially flows through the heat exchange coil 46 in the absorber 13 and the heat exchange coil 43 in the condenser 10 to complete circulation, so as to achieve the purpose of cooling the working medium in the absorber 13 and the condenser 10, meanwhile, the low-temperature working medium flowing out of the heat exchange coil 44 in the generator 11 flows into the inner pipeline 5 of the photo-thermal and photo-cooling solar energy conversion device 15 through the valve 20, and flows through the valve 16 and flows back to the heat exchange coil 44 of the generator 11 after being heated, so as to realize the heating of the working medium in the generator.

The technical scheme of the invention can at least achieve the following technical effects:

1) the solar energy conversion device collects solar heat energy to provide heat for the generator by utilizing the photo-thermal and photo-cold solar energy conversion device, meanwhile, adsorbate in the device is desorbed with the adsorbent, the adsorbent in the device absorbs the adsorbate at night, the adsorption heat generated in the adsorption process can provide heat for the night operation of the generator, and meanwhile, cold energy is generated in the evaporation process of adsorbate liquid and can cool the condenser and the absorber. The two-stage utilization of solar energy is realized, and the utilization rate of the solar energy is improved.

2) The invention can provide heat for the evaporator of the absorption refrigeration system and can also provide cold for the condenser and the absorber of the absorption refrigeration system at night, thereby reducing the auxiliary heating quantity of the solar absorption refrigeration system at night and improving the refrigeration efficiency.

3) The solar energy adsorption and absorption cascade refrigeration and heating system has the advantages of novel design, simple structure, easy realization, wide popularization and application in various building projects, and wide market practical prospect.

Drawings

The attached drawing is a schematic diagram of a solar adsorption and absorption cascade refrigeration and heating system

Second attached drawing is a side schematic diagram of photo-thermal and photo-cold solar energy conversion device

The third attached drawing is a schematic plan view of the photo-thermal and photo-cold solar energy conversion device

The meanings of the reference symbols in the figures are as follows:

1-a housing; 2-a closed cavity; 3-a condenser lens; 4-sun rays; 5-an inner conduit; 6-an adsorbent; 7-a liquid collecting cavity; 8-wall surface; 9-an evaporator; 10-a condenser; 11-a generator; 12-an absorber; 13-solution heat exchanger; 14-a ground heat exchanger; 15-a photo-thermal, photo-cold solar energy conversion device; 16-a valve; 17-a valve; 18-a valve; 19-a valve; 20-a valve; 21-a valve; 22-a valve; 23-an expansion valve; 24-a valve; 25-a pump; 26-outer pipe; 27-outer tubing; 28-outer tubing; 29-outer tubing; 30-an outer pipe; 31-outer tubing; 32-outer tubing; 33-outer tubing; 34-outer tubing; 35-outer tubing; 36-outer tubing; 37-outer tubing; 38-outer tubing; 39-outer tubing; 40-outer tubing; 41-outer pipe; 42-outer tubing; 43-heat exchange coil inside the generator; 44-heat exchange coil inside the generator; 45-heat exchange coil in the generator; 46-heat exchange coil inside the absorber; 47-outer tubing; 48-outer tubing; 49-pump; 50-pump

Detailed Description

The following detailed description of the embodiments of the present invention is provided in conjunction with the accompanying drawings to enable those skilled in the art to more clearly understand the present invention, but not to limit the scope of the present invention.

The invention relates to a solar energy adsorption and absorption cascade coupling refrigerating and heating system, which is characterized by comprising: an evaporator 9, a condenser 10, a generator 11, a solution heat exchanger 12, an absorber 13,

pumps

25, 49 and 50, a ground heat exchanger 14, a photo-thermal and photo-cold solar energy conversion device 15 and an expansion valve 23; the condenser 10, the expansion valve 23, the evaporator 9, the absorber 13, the pump 25, the solution heat exchanger 12, the generator 11 and the valve 24 form an absorption refrigeration circulation pipeline; the heat exchange coil 44, the pump 49, the valve 17, the pipeline 35, the photo-thermal and photo-cold solar energy conversion device 15 and the valve 22 in the generator 11 form a daytime heating circulating pipeline of the absorption refrigeration heating system; the heat exchange coil 46 in the absorber 13, the heat exchange coil 43 in the condenser 10, the valve 19, the ground heat exchanger 14 and the pump 50 are connected in sequence to form a daytime cooling circulation pipeline of the absorption refrigeration cooling system; the heat exchange coil 44, the pump 49, the valve 16, the photo-thermal and photo-cold solar energy conversion device 15 and the valve 20 in the generator 11 form a night heating circulation pipeline of the absorption refrigeration and heating system; the heat exchange coil 43, the valve 18, the photo-thermal and photo-cold solar energy conversion device 15, the valve 21, the pump 50 and the heat exchange coil 46 in the absorber 13 in the condenser 10 are connected in sequence to form a night circulation pipeline of the absorption refrigeration and cooling system. Different circulation modes in the daytime and at night are realized by switching the valves.

The light and heat, cold solar energy conversion equipment of light, its characterized in that includes: the device comprises a shell 1, a closed cavity 2, a condenser 3, an inner pipeline 5, an adsorbent 6, a liquid collecting cavity 7 and a wall surface 8, wherein the wall surface 8 and the condenser 3 form the closed liquid collecting cavity 7, the inner pipeline 5 penetrates through the center line of the liquid collecting cavity 7, and the adsorbent 6 is fixed on the outer surface of the inner pipeline 5; the wall surface 8, the condenser 3, the inner pipeline 5 and the adsorbent 6 form a solar energy utilization unit which can be cooled and heated; the units are arranged in an array and are communicated through an inner conduit 5. The walls 8 and the housing 1 in the array form a closed chamber 2 which communicates with the outside via

ducts

36 and 38.

Therefore, the absorption refrigeration and the adsorption refrigeration are coupled, in the daytime, the system utilizes the photo-thermal and photo-cold solar energy conversion device to collect solar heat energy to provide heat for the generator, meanwhile, the adsorbate in the device is desorbed with the adsorbent, at night, the adsorbent in the device absorbs the adsorbate, the adsorption heat generated in the adsorption process can provide heat for the night operation of the generator, meanwhile, the adsorbate liquid generates cold energy in the evaporation process, and the cold energy can cool the condenser and the absorber. The device realizes two-stage utilization of solar refrigeration and heating, realizes night operation of the absorption refrigeration system in a mode without an auxiliary heat source, and improves the utilization rate of solar energy.

During the daytime, the solar rays irradiate the condenser 3, the collected solar rays irradiate the adsorbent 6, the adsorbent 6 is heated, the adsorbent 6 desorbs adsorbate vapor, the adsorbate vapor is condensed into liquid on the inner surface of the wall surface 8 and releases phase change latent heat, the released heat is transferred from the inner side to the outer side of the wall surface 8 in a heat conduction mode, the working medium on the outer side of the wall surface 8 is heated, and the temperature of the working medium is increased. Under the drive of the pump 49, the heated working medium flows out of the closed cavity 2, and flows through the pipeline 38, the pipeline 40, the valve 22 and the pipeline 48 in sequence to enter the heat exchange coil 44 in the generator 11. In the generator 11, the high-temperature working medium heats the dilute solution in the generator 11, the water in the dilute solution evaporates, the water vapor formed after evaporation enters the condenser 10 through the pipeline 29, the cooled working medium flows out of the generator 11, sequentially flows through the pipeline 47, the water pump 49, the valve 17, the pipeline 35 and the pipeline 36, and finally returns to the closed cavity 2 in the photo-thermal and photo-cold solar energy conversion device 15 to complete the absorption refrigeration daytime heating cycle.

In the daytime, the high-temperature working medium entering the buried pipe exchanges heat with soil, the temperature of the working medium is reduced, the cooled working medium flows through the pipeline 31 to enter the heat exchange coil 46 in the absorber 13 under the driving of the pump 50, in the absorber 13, the low-temperature working medium cools the concentrated solution in the absorber 13, the water flowing out from the evaporator 9 enters the absorber 13 through the pipeline 27 to be mixed with the cooled concentrated solution to form a dilute solution, the working medium after temperature rise enters the heat exchange coil 43 in the condenser 10 through the pipeline 42, in the condenser 10, the working medium after the primary temperature rise cools the water vapor in the condenser 10, the temperature of the working medium rises again, the water vapor undergoes phase change to release latent heat, the water after the phase change throttles by the expansion valve 23 to enter the evaporator 9, the working medium after the secondary temperature rise flows out of the condenser 10, and flows through the pipeline 33, the valve 19 and the pipeline 32 in sequence to return to the buried pipe heat exchanger 14 to complete the daytime cooling circulation.

At night, no sunlight irradiates, the temperature of the adsorbent 6 is reduced, the adsorbent 6 adsorbs adsorbate vapor and releases adsorption heat, the released heat is transmitted from the outer side to the inner side of the inner pipeline 5 in a heat conduction mode, the working medium in the inner pipeline 5 is heated, and the temperature of the working medium is increased. Driven by a pump 49, the heated working medium flows out of the closed cavity 2, and then flows through a pipeline 37, a valve 20 and a pipeline 48 to enter a heat exchange coil in the generator. In the generator 11, the high-temperature working medium heats the dilute solution in the generator 11, the water in the dilute solution evaporates, the water vapor formed after evaporation enters the condenser 10 through the pipeline 29, the cooled working medium flows out of the generator 11, sequentially flows through the pipeline 47, the water pump 49, the valve 16 and the pipeline 39, and finally returns to the sealed cavity 2 in the photo-thermal and photo-cold solar energy conversion device 15 to complete the night heating cycle.

At night, the adsorbent 6 adsorbs adsorbate vapor so that the pressure of the adsorbate vapor in the liquid collection cavity 7 is reduced, the adsorbate liquid at the bottom of the liquid collection cavity 7 evaporates, the adsorbate evaporates to absorb heat, the absorbed heat is transmitted to the inner side from the outer side of the wall surface 8 in a heat conduction mode, the working medium on the outer side of the wall surface 8 is cooled, and the temperature of the working medium is reduced. Driven by a pump 50, the cooled working medium flows out of the closed cavity 2, sequentially flows through a pipeline 38, a valve 21, a pipeline 31 and the pump 50, enters a heat exchange coil 46 in an absorber 13, the low-temperature working medium cools a concentrated solution in a generator 11 in the absorber 13, water flowing out of an evaporator 9 enters the absorber 13 through a pipeline 27 and is mixed with the cooled concentrated solution to form a dilute solution, the heated working medium enters a heat exchange coil 43 in a condenser 10 through a pipeline 42, the working medium subjected to primary heating cools water vapor in the condenser 10, the temperature of the working medium is raised again, the water vapor generates phase change to release latent heat, the water subjected to phase change throttles through an expansion valve 23 and enters the evaporator 9, the working medium subjected to secondary heating flows out of the condenser, sequentially flows through a pipeline 33, a valve 18, a pipeline 34 and a pipeline 36, and finally returns to photo-thermal, The closed cavity 2 in the light-cooled solar energy conversion device 15 completes the cooling cycle at night.

Claims

1. The utility model provides a solar energy adsorbs, absorbs step refrigeration and heating system which characterized in that includes: evaporator (9), condenser (10), generator (11), solution heat exchanger (12), absorber (13), first pump (25), second pump (49), third pump (50), ground heat exchanger (14), light and heat, light and cold solar energy conversion device (15) and expansion valve (23), wherein, light and heat, light and cold solar energy conversion device (15) includes: the device comprises a shell (1), a closed cavity (2), a condenser (3), an inner pipeline (5), an adsorbent (6), a liquid collecting cavity (7) and a wall surface (8), wherein the wall surface (8) and the condenser (3) form the closed liquid collecting cavity (7), the inner pipeline (5) penetrates through the center line of the liquid collecting cavity (7), and the adsorbent (6) is fixed on the outer surface of the inner pipeline (5); the wall surface (8), the condenser (3), the inner pipeline (5) and the adsorbent (6) form a solar energy utilization unit capable of refrigerating and heating; the solar energy utilization units are arranged in an array and communicated through the inner pipeline (5); the wall surface (8) in the array and the shell (1) form a closed cavity (2); the condenser (10), the expansion valve (23), the evaporator (9), the absorber (13), the first pump (25), the solution heat exchanger (12), the generator (11) and the first valve (24) form an absorption refrigeration cycle pipeline; a heat exchange coil (44), a second pump (49), a second valve (17), a photo-thermal and photo-cold solar energy conversion device (15) and a third valve (22) in the generator (11) form a daytime heating circulation pipeline; a heat exchange coil (46) in the absorber (13), a heat exchange coil (43) in the condenser (10), a fourth valve (19), a ground heat exchanger (14) and a third pump (50) are connected in sequence through pipelines to form a daytime cooling circulation pipeline; a heat exchange coil (44), a second pump (49), a fifth valve (16), a photo-thermal and photo-cold solar energy conversion device (15) and a sixth valve (20) in the generator (11) form a night heating circulation pipeline; a heat exchange coil (43) in the condenser (10), a seventh valve (18), a photo-thermal and photo-cold solar energy conversion device (15), an eighth valve (21), a third pump (50) and a heat exchange coil (46) in the absorber (13) are connected in sequence through pipelines to form a night cooling circulation pipeline; different circulation modes in the daytime and at night are realized by switching the valves.

2. The solar adsorption, absorption cascade refrigeration and heating system as claimed in claim 1, wherein the light-heat and light-cold solar energy conversion device (15) is communicated with the heat exchange coil (43) in the condenser (10) through a first pipeline (36), a second pipeline (34), a seventh valve (18) and a third pipeline (33); the photo-thermal and photo-cold solar energy conversion device (15) is communicated with the heat exchange coil (46) in the absorber (13) through a fourth pipeline (38), an eighth valve (21), a fifth pipeline (41), a sixth pipeline (31) and a third pump (50).

3. The solar adsorption, absorption cascade refrigeration and heating system as claimed in claim 2, wherein the light-heat and light-cold solar energy conversion device (15) is communicated with the heat exchange coil (43) in the generator (11) through a first pipeline (36), a seventh pipeline (35), a second valve (17), an eighth pipeline (47), a second pump (49); the photo-thermal and photo-cold solar energy conversion device (15) is communicated with a heat exchange coil (44) in the generator (11) through a fourth pipeline (38), a ninth pipeline (40), a third valve (22) and a tenth pipeline (48).

4. The solar adsorption, absorption cascade refrigeration and heating system as claimed in claim 3, wherein the light-heat and light-cold solar energy conversion device (15) is communicated with the heat exchange coil (43) in the generator (11) through an eleventh pipeline (39), a fifth valve (16), a twelfth pipeline (47), a second pump (49); the photo-thermal and photo-cold solar energy conversion device (15) is communicated with a heat exchange coil (44) in the generator (11) through a thirteenth pipeline (37), a sixth valve (20) and a fourteenth pipeline (48).