JP7173098B2 - Cold generation method - Google Patents

Description

The present disclosure relates to adsorption heat pump systems and cold generation methods.

2. Description of the Related Art Adsorption heat pumps used for air conditioners, refrigerators, freezers, etc. are known, which repeat adsorption and desorption phenomena between adsorbents such as silica gel and zeolite and adsorbates such as water and ammonia to convert them into thermal energy.
For example, Non-Patent Document 1 describes an adsorption chiller that adsorbs and desorbs water vapor using a zeolite-based adsorbent and desorbs the adsorbent using hot water heated to about 60 to 75 ° C. by a solar collector. disclosed.

Further, in Patent Document 1, an evaporator, a first adsorber, and a second adsorber are provided, the first adsorber adsorbs the adsorbate, the evaporator generates cold heat, and the adsorbate adsorbed by the first adsorber is disclosed in an adsorption heat pump that adsorbs in a second adsorber and produces cold in a first adsorber.

Patent No. 6065882

Journal of the Japan Society of Mechanical Engineers 2010. 1 Vol. 113 No.1094

The adsorption chiller disclosed in Non-Patent Document 1 adsorbs water vapor from the evaporator with an adsorbent, then condenses the desorbed water vapor with hot water into liquid (water), and evaporates the condensed water again. It is a so-called single-stage adsorption heat pump that returns to the vessel.
On the other hand, a multi-stage adsorption heat pump that performs adsorption and desorption multiple times (multi-stage) using a plurality of adsorbers as disclosed in Patent Document 1 is more efficient than a single-stage adsorption heat pump. can be done.

However, in the multi-stage heat pump, the adsorbent in the latter stage needs to use an adsorbent with a higher adsorption force for the adsorbate than the adsorbent in the preceding stage, and a higher temperature heat source is required for regeneration (desorption). For example, with hot water heated to 60 to 75° C. by a solar collector as disclosed in Non-Patent Document 1, it is difficult to desorb the adsorbate from the subsequent adsorbent.
Further, for example, desorption by heating the adsorbent with electricity or the like hinders the advantage of energy saving that the adsorption heat pump originally has.

An object of the present disclosure is to provide an adsorption heat pump system and a method for generating cold energy that can efficiently generate cold energy using sunlight.

<1> an evaporator in which the adsorbate evaporates to generate cold heat;
a first adsorber including a first adsorbent that adsorbs the adsorbate evaporated in the evaporator;
a second adsorber including a second adsorbent that adsorbs the adsorbate desorbed from the first adsorbent;
A heating source for heating the second adsorber, comprising a heat collecting plate that absorbs sunlight and raises the temperature, a collector that collects the sunlight on the heat collecting plate, and a heat source from the heat collecting plate a solar heat collector that includes a temperature-increasing auxiliary means for at least one of a heat insulating material that insulates radiant heat, and is capable of increasing the temperature of the heat collecting plate to 160° C. or higher by the sunlight;
an adsorption heat pump system.
<2> The adsorption heat pump system according to <1>, wherein the adsorption capacity of the second adsorber is larger than the adsorption capacity of the first adsorber.
<3> A bypass pipe that bypasses the first adsorber and connects the evaporator and the second adsorber, wherein the adsorbate desorbed from the second adsorbent is the bypass pipe The adsorption heat pump system according to <1> or <2>, which also serves as a condenser for condensing the adsorbate introduced into the evaporator through the heat pump system.
<4> At least selected from the group consisting of a heat exchanger for heat exchange of the evaporator, a heat exchanger for heat exchange of the first adsorbent, and a heat exchanger for heat exchange of the second adsorbent The adsorption heat pump system according to any one of <1> to <3>, comprising one heat exchanger.
<5> The solar heat collector heats the second adsorbent via at least one heat transfer means selected from the group consisting of a heat exchanger, a heat exchange fluid, a liquid feed pump, and a heat pipe <1 > The adsorption heat pump system according to any one of <4>.
<6> The adsorption heat pump system according to any one of <1> to <4>, wherein the heat collecting plate and the second adsorbent are arranged in the same heat insulating structure including the heat insulating material. .
<7> The solar heat collector includes, as the heat insulating material, a selectively transmitting material that selectively transmits the sunlight to the heat collecting plate, and as the heat collecting plate, the selectively transmitting material transmits the sunlight. The adsorption heat pump system according to any one of <1> to <6>, which has a double optical heat insulation structure including a selective absorption material that selectively absorbs the sunlight.
<8> The selective transmission material has an average transmittance of 80% or more in a sunlight region with a wavelength of 0.3 μm to 2.5 μm and a thermal conductivity of 0.5 W/m/K or less,
The selective absorption material has an average absorptivity of 80% or more in the sunlight region, and an average transmittance of 20% or more in the radiation region with a wavelength of more than 2.5 μm to 20 μm. The adsorption heat pump system according to <7>, which has an emissivity of 60% or less.
<9> Any one of <1> to <8>, wherein the first adsorbent is at least one selected from the group consisting of mesoporous silica, Al-MOF and Zr-MOF, and the second adsorbent is zeolite 1. The adsorption heat pump system according to one.
<10> Using the adsorption heat pump system according to any one of <1> to <9>,
Adsorbing the adsorbate with the first adsorbent and evaporating the adsorbate with the evaporator to generate cold energy;
a step of desorbing the adsorbate from the first adsorbent by adsorbing the adsorbate with the second adsorbent to generate cold energy;
After repeating multiple times alternately,
A method for generating cold energy, comprising regenerating the second adsorbent by heating the second adsorbent with the solar collector to desorb the adsorbate.
<11> The adsorption heat pump system includes the bypass pipe according to <3>, and introduced from the evaporator into the second adsorber through the bypass pipe before the step of regenerating the second adsorbent. The method for generating cold heat according to <10>, including the step of adsorbing the adsorbate with the second adsorbent.

According to the present disclosure, an adsorption heat pump system and a method for generating cold energy are provided, which are capable of efficiently generating cold energy using sunlight.

1 is a schematic diagram showing the configuration of an adsorption heat pump system according to a first embodiment of the present disclosure; FIG. It is a schematic diagram showing an example of composition of a solar heat collector in an adsorption heat pump system of a first embodiment. FIG. 4 is a diagram showing an example of the relationship between optical properties of a selectively transmissive material and a selectively absorbing material that can be used for a solar collector in the adsorption heat pump system of the present disclosure; Fig. 10 is a graph showing the results of a temperature elevation experiment using sunlight using a heat collector having a double optical heat insulation structure in which a selective transmission material and a selective absorption material are stacked in a vacuum vessel. FIG. 2 is a schematic diagram showing the configuration of an apparatus in which a heat collector having a double optical heat insulation structure in which a selective transmission material and a selective absorption material are stacked in a vacuum vessel was used to conduct a temperature elevation experiment using sunlight. It is a graph which shows the highest attainment temperature when the structure of a temperature raising means is changed in a solar simulation. FIG. 2 is a schematic diagram showing the configuration of an adsorption heat pump system according to a second embodiment of the present disclosure; It is a schematic diagram showing the configuration of a heat collector/second adsorber (an example of a solar heat collector) in the adsorption heat pump system of the second embodiment. FIG. 8 is a schematic diagram showing the positional relationship of the main parts of the heat collector/second adsorber shown in FIG. 7 viewed from the sunlight incident side; FIG. 4 is a schematic diagram showing the flow of water vapor and heat exchange fluid in the heat storage mode of the adsorption heat pump system of the second embodiment of the present disclosure; FIG. 4 is a schematic diagram showing the flow of water vapor and heat exchange fluid in the first stage output mode of the adsorption heat pump system of the second embodiment of the present disclosure; FIG. 4 is a schematic diagram showing the flow of water vapor and heat exchange fluid in the second stage output mode of the adsorption heat pump system of the second embodiment of the present disclosure; FIG. 2 is a schematic diagram showing the configuration of a single-stage adsorption heat pump system used for simulating temperature changes in an evaporator and an adsorber; 11 is a diagram showing temperature changes of the evaporator and the adsorber simulated by the single-stage adsorption heat pump system having the configuration shown in FIG. 10; FIG. FIG. 2 is a schematic diagram showing the configuration of a multi-stage adsorption heat pump system used for simulating temperature changes in an evaporator and an adsorber; FIG. 13 is a schematic diagram showing the flow of water vapor in a simulation using the multi-stage adsorption heat pump system having the configuration shown in FIG. 12; FIG. 13 is a diagram showing temperature changes of the evaporator and the adsorber simulated by the single-stage adsorption heat pump system having the configuration shown in FIG. 12; 4 is a graph comparing cooling outputs based on simulation results of a single-stage adsorption heat pump system and simulation results of a multi-stage adsorption heat pump system;

Embodiments of an adsorption heat pump system and a method for generating cold energy according to the present disclosure will be described below with reference to the drawings.
The adsorption heat pump system according to the present disclosure includes an evaporator that evaporates adsorbate to generate cold heat, a first adsorber that includes a first adsorbent that adsorbs the adsorbate evaporated in the evaporator, and a first adsorbent. and a second adsorber containing a second adsorbent for adsorbing the adsorbate desorbed from. Furthermore, in the adsorption heat pump system according to the present disclosure, as a heating source for heating the second adsorption device, a heat collecting plate that absorbs sunlight and raises its temperature, and a collector that collects sunlight on the heat collecting plate and at least one of a heat insulating material that insulates radiant heat from the heat collecting plate, and a solar heat collector capable of raising the temperature of the heat collecting plate to 160° C. or higher by sunlight.
In the adsorption heat pump system according to the present disclosure having such a configuration, the first adsorbent adsorbs the adsorbate, the adsorbate evaporates in the evaporator to generate cold heat, and the second adsorbent absorbs the adsorbate. The adsorption desorbs the adsorbate from the first adsorbent to generate cold heat, and the solar collector heats the second adsorbent to desorb the adsorbate, thereby regenerating the second adsorbent.

[First embodiment]
FIG. 1 is a schematic diagram showing the configuration of a heat pump system according to the first embodiment of the present disclosure. The adsorption heat pump system of the first embodiment includes a heat collector 10 , an evaporator/condenser 20 serving as both an evaporator and a condenser, a first adsorber 30 and a second adsorber 40 . The heat collector 10, the evaporator/condenser 20, the first adsorber 30, and the second adsorber 40 are provided with heat exchangers 12, 22, 32, and 42 for exchanging heat with the outside using a heat exchange fluid. is provided.

(evaporator/condenser)
The evaporator/condenser 20 has both a function as an evaporator and a function as a condenser. The liquid adsorbate contained in the evaporator/condenser 20 may be used when the pressure of the gas inside the evaporator/condenser 20 decreases (depressurization) or when the temperature of the liquid (liquid adsorbate) rises ( Heating) evaporates the adsorbate, producing cold energy. Also, the gaseous adsorbate introduced into the evaporator/condenser 20 from the outside is deprived of thermal energy, and the adsorbate is condensed. As the adsorbate, known adsorbates such as water, ammonia and alcohol can be used.
The evaporator/condenser 20 is connected to the first adsorber 30 via a connecting pipe 50B. The adsorbate can move between the evaporator/condenser 20 and the first adsorber 30 by opening the on-off valve 60B provided in the connecting pipe 50B.
In addition, the evaporator/condenser 20 is provided with a heat exchanger 22 for exchanging heat with a heat exchange fluid. Cold heat generated by the evaporator/condenser 20 can be transferred to the outside via heat exchange fluid flowing through connection pipes 24A and 24B that are connected to the heat exchanger 22 . It is also possible to cool and condense the gaseous adsorbate introduced into the evaporator/condenser 20 with the heat exchanger 22 .

(first adsorber)
The first adsorber 30 contains a first adsorbent capable of adsorbing and desorbing adsorbates. As the first adsorbent, for example, mesoporous silica, Al--MOF, Zr--MOF, etc. can be used. Examples of Zr-MOF include MOF-801.
The first adsorber 30 is connected to the second adsorber 40 via a connecting pipe 50C. The adsorbate can move between the first adsorber 30 and the second adsorber 40 by opening the on-off valve 60C provided in the connecting pipe 50C.
In addition, the first adsorber 30 is provided with a heat exchanger 32 for exchanging heat with a heat exchange fluid. Heat generated in the first adsorber 30 can be transferred to the outside via heat exchange fluid flowing through connecting pipes 34A and 34B that connect to the heat exchanger 32 .

(second adsorber)
The second adsorber 40 contains a second adsorbent capable of adsorbing and desorbing adsorbates. The second adsorbent of the second adsorber 40 promotes desorption of the adsorbate from the first adsorbent by adsorbing the adsorbate that moves from the first adsorber 30 through the connecting pipe 50C, and the second adsorbate of the first adsorber 30 A material is selected that desorbs the adsorbate with heat at a regeneration temperature higher than that of the adsorbent. The second adsorbent is preferably an adsorbent whose adsorbate is desorbed when heated at 160° C. or higher. As the second adsorbent, for example, zeolite such as Y-type zeolite can be preferably used.
The second adsorber 40 is connected to the evaporator/condenser 20 via a bypass pipe 50A that bypasses the first adsorber 30 . Adsorbate can move between the second adsorber 40 and the evaporator/condenser 20 by opening the bypass on-off valve 60A provided in the bypass pipe 50A. By providing a bypass pipe 50A that connects the second adsorber 40 and the evaporator/condenser 20, and moving the adsorbate desorbed by the second adsorber 40 to the evaporator/condenser 20, the second It is possible to easily regenerate the adsorber (second adsorbent). Alternatively, the adsorbate in the evaporator/condenser 20 can be moved to the second adsorber 40 through the bypass pipe 50A and adsorbed by the second adsorbent.
In addition, the second adsorber 40 is provided with a heat exchanger 42 for exchanging heat with a heat exchange fluid. The heat generated in the second adsorber 40 can be transferred to the outside via a heat exchange fluid flowing through connecting pipes 44A, 44B that connect to the heat exchanger 42 .

The combination of the first adsorbent in the first adsorber 30 and the second adsorbent in the second adsorber 40 allows the desorbed adsorbate to be desorbed against the first equilibrium pressure after desorbing the adsorbate in the first adsorber. The combination is preferably such that the second equilibrium pressure after adsorption by the second adsorption device 40 is equal to or lower than the first equilibrium pressure. Such a combination makes it possible to reliably perform the operation of causing the adsorbate desorbed by the first adsorber 30 to be adsorbed by the second adsorber 40 .

Moreover, it is preferable that the adsorption capacity of the second adsorber 40 is larger than the adsorption capacity of the first adsorber 30 . Since the adsorption capacity of the second adsorber 40 is larger than the adsorption capacity of the first adsorber 30 , the adsorbate of the first adsorber 30 can be reliably adsorbed by the second adsorber 40 .
In addition, the reaction mechanism of adsorption and desorption by the first adsorbent and the second adsorbent in the present disclosure is not limited, for example, by reacting with the adsorbate at a pressure below the saturated vapor pressure of the adsorbate, the pressure of the system It is sufficient if the pressure can be lowered below the saturated vapor pressure. The reaction here includes physical adsorption, chemical adsorption, absorption, chemical reaction, and the like.

(solar heat collector)
The solar heat collector 10 (sometimes simply referred to as “collector” in the present disclosure) is a heating source for heating and regenerating (desorbing) the second adsorbent of the second adsorber 40. be. The heat collector 10 is provided with a heat exchanger 12 for exchanging heat with a heat exchange fluid. The heat exchanger 12 of the heat collector 10 is connected to the heat exchanger 42 of the second adsorber 40 by connecting pipes 14A and 14B. The heat of the collector 10 can be transferred to the second adsorber 40 via the heat exchange fluid flowing through the heat exchangers 12 and 42 by opening the on-off valve 70D provided in the connecting pipe 14A. A known heat medium can be used as the heat exchange fluid flowing through the heat exchangers 12 and 42 . Normally low boiling oils such as Dowtherm® A (3:7 mixture of biphenyl and diphenyl ether) can be used.

FIG. 2 is a schematic diagram showing an example of the solar collector 10 in the adsorption heat pump system of this embodiment. A solar heat collector 10A shown in FIG. A material 92 and the like are provided.
In the present disclosure, “selectively transmitting sunlight” means that the average transmittance in the sunlight region with a wavelength of 0.3 μm to 2.5 μm is preferably 80% or more, and “selectively absorbing sunlight” It is preferable that the average absorptivity in the sunlight region with a wavelength of 0.3 μm to 2.5 μm is 80% or more.

Preferably, the selective transmission material 58 has an average transmittance of 80% or more in the sunlight region with a wavelength of 0.3 μm to 2.5 μm, and has high heat insulating properties against heat emitted from the selective absorption material. Specifically, the selective transmission material 58 has an average transmittance of 80% or more in the sunlight region with a wavelength of 0.3 μm to 2.5 μm and a thermal conductivity of 0.5 W/m/K or less. preferable. As the selective transmission material 58, airgel such as silica airgel and PMSQ airgel, and transparent resin such as polymethyl methacrylate resin (PMMA) can be suitably used from the viewpoint of light transmittance and heat insulation.

From the viewpoint of absorbing sunlight as much as possible and converting it into heat energy, the selective absorption material 48 is preferably a material having an average absorption rate of 80% or more in the sunlight region with a wavelength of 0.3 μm to 2.5 μm. For example, a material that exhibits wavelength selectivity in a multilayer film such as TiNOX (registered trademark), a material that exhibits wavelength selectivity due to the physical properties of a single material or composite material such as black Ni, black Cr, and book Cu, Examples include materials that exhibit wavelength selectivity depending on their structure.

In addition, in order to improve the heat insulation of the heat collector 10, the selective absorption material 48 preferably has a high absorptivity of sunlight and a low emissivity in the wavelength band through which the selective transmission material 58 easily transmits. Specifically, the selective absorption material 48 has an average absorptance of 80% or more in the sunlight region with a wavelength of 0.3 μm to 2.5 μm, and the selective transmission material 58 in the radiation region with a wavelength of more than 2.5 μm to 20 μm. When there is a wavelength band in which the transmittance of is 20% or more, it is preferable that the average emissivity in this wavelength band is 60% or less. As the selective absorption material 48, TiNOX (registered trademark) can be particularly preferably used from the viewpoint of high sunlight absorptivity and low infrared light emissivity.

A heat transfer section 94 and a heat insulating material 92 are arranged on the back side of the selective absorption material 48 (the side opposite to the side that receives sunlight).
The heat transfer part 94 should have a higher thermal conductivity than the heat insulating material 92. Examples of the heat insulating material 92 include a quartz fiber filter and airgel. A heat pipe, a metal, or the like may be used as the heat transfer section 94 .

The selectively transmissive material 58 , the selectively absorbing material 48 , the heat transfer section 94 , and the heat insulating material 92 are housed inside the window 56 and the stainless steel housing 90 . A vacuum heat insulating portion 98 for creating a vacuum environment is provided around the selectively permeable material 58 , the selective absorbing material 48 , the heat transfer portion 94 and the heat insulating material 92 .
A heat exchanger 12 is provided on the back side (the side opposite to the light receiving surface) of the solar heat collector 10A. A heat exchange fluid contact portion 96 of the heat transfer portion 94 of the solar collector 10A is configured to contact the heat exchange fluid inside the heat exchanger 12 .

The sunlight transmitted through the window 56 and the selective transmission material 58 is absorbed by the selective absorption material 48 and converted into heat energy to raise the temperature. When silica airgel is used as the selective transmission material 58, the sunlight is transmitted, and the radiant heat from the heated selective absorption material 48 is effectively blocked, so that the heat is hardly radiated to the light receiving surface side. A combination of the selective transmission material 58 and the selective absorption material 48 having the optical properties described above constitutes a so-called double optical heat insulating structure.

A heat insulating material 92 is arranged on the rear side of the heat transfer section 94, and the outer circumference is vacuum-insulated. With such a heat insulating structure, the selective absorption material 48 can be heated to 160° C. or higher only by sunlight. The heat generated in the selective absorption material 48 is efficiently transferred to the heat transfer section 94 and further through the heat exchange fluid in the heat exchanger 12 via the heat exchange fluid contact section 96 to the outside, i. The heat is transferred to the two adsorbers 40 .
The heat transfer means from the heat collector 10 to the second adsorber 40 is not limited, and can be selected from heat exchangers, heat exchange fluids, liquid feed pumps, heat pipes, and the like.

FIG. 3 is a diagram showing an example of the relationship between the optical properties of a selective transmission material and a selective absorption material. A selective transmission material 58 having a solar light transmittance of 0.9 and an infrared light transmittance of 0.1, and a selective absorption material 48 having a solar light absorption rate of 0.9 and an infrared light emissivity of 0.1. , 0.9 out of 1 sun of sunlight is transmitted through the selective transmission material, and 0.81 sun is converted into heat by the selective absorption material. Furthermore, 0.1 black of infrared light is emitted from the selective absorption material, but the transmission of infrared light is blocked by the selective transmission material, and the radiation loss to the external environment remains at 0.01 black. Thereby, the radiation loss can be suppressed to about 1/100. Further, by combining such double optical heat insulation and vacuum heat insulation, it is possible to raise the temperature extremely efficiently.

FIG. 4A shows the results of a temperature rise experiment by sunlight using a collector with a double optical heat insulation structure in which a selective transmission material (silica airgel) and a selective absorption material (TiNOX) are stacked in a vacuum vessel. graph. The heat collector used in the experiment has the schematic configuration shown in FIG. A selective transmission material (silica airgel) and a glass fiber filter are arranged as materials. It was confirmed that the heat collector with such a configuration raises the temperature up to 275° C. near the selective absorption material without concentrating the sunlight (FIG. 4A).

FIG. 5 is a graph showing the maximum temperature reached when a temperature raising experiment was conducted using a solar simulator with the configuration of the temperature raising means changed as follows.
Composition No. 1: Black material + selective transmission material Composition No. 2: Selective absorption material + selective transmission material Composition No. 3: Selective absorption material + vacuum insulation Composition No. 4: Selective absorption material + selective transmission material + vacuum insulation Composition No. 1 here The black material in is an aluminum plate coated with a black pigment paint.
The temperature can be raised to 160° C. or higher by any means, the temperature can be raised to about 230° C. only by the double optical heat insulation (configuration number 2), and the temperature can be efficiently raised to a high temperature by the double optical heat insulation. I understand.

Next, a method of generating cold using the adsorption heat pump system 100 shown in FIG. 1 will be described. In the following, on-off valves other than those specified as "open" are closed.

(Cold generation in evaporator/condenser)
By opening the on-off valve 60B in a state in which the liquid adsorbate is stored in the evaporator/condenser 20, the adsorbate evaporated in the evaporator/condenser 20 moves to the first adsorbent 30 through the connecting pipe 50B and is transferred to the first adsorbate. It is adsorbed by one adsorber 30 . Due to the adsorption in the first adsorber 30, the pressure in the evaporator/condenser 20 is reduced. The adsorbate evaporates in the depressurized evaporator/condenser 20, and the latent heat of vaporization generates cold heat. After opening the on-off valve 70A and supplying the room temperature heat exchange fluid to the heat exchanger 22 from the connection pipe 24A for heat exchange, the cold heat generated in the evaporator/condenser 20 is discharged from the connection pipe 24B. It can be taken outside.
On the other hand, the heat generated as the heat of adsorption in the first adsorber 30 is taken out by supplying the heat exchange fluid of room temperature to the heat exchanger 32 and exchanging heat. The heat taken out to the outside may be used for heating or the like.
In addition, the supply and discharge of the heat exchange fluid in the heat exchanger 22 are forcibly circulated by a pump (not shown) through the connection pipes 24A and 24B, and the pump (not shown) is driven to open and close the valve. 70A can be configured to open. The supply and discharge of the heat exchange fluid in the heat exchangers 32 and 42 and the opening of the on-off valves 70B and 70C can be configured in the same manner.

(Generation of cold heat in the first adsorber)
When the adsorption in the first adsorber 30 becomes saturated, the on-off valve 60B is closed and the on-off valve 60C is opened to regenerate (desorb) the first adsorbent.
The second adsorbent of the second adsorber 40 has a higher adsorptive power for the adsorbate than the first adsorbent of the first adsorber 30, and the adsorption capacity of the second adsorbent allows the first adsorption of the first adsorber 30 The adsorbate adsorbed on the material is desorbed, moves to the second adsorber 40 through the connecting pipe 50C, and is adsorbed by the second adsorbent of the second adsorber 40. - 特許庁As a result, the pressure in the first adsorber 30 is reduced. Cold heat is generated by desorption in the first adsorber 30, and the first adsorbent is regenerated. Cold heat can be extracted from the first adsorber 30 by opening the on-off valve 70B and supplying room temperature heat exchange fluid to the heat exchanger 32 for heat exchange.
On the other hand, the heat generated as the heat of adsorption in the second adsorber 40 is taken out to the outside by supplying a heat exchange fluid at room temperature to the heat exchanger 42 to perform heat exchange.

(Evaporation by the second adsorber/Adsorption of adsorbate from the condenser)
By alternately repeating "generation of cold heat in the evaporator/condenser" and "generation of cold heat in the first adsorber", the evaporation speed and adsorption speed gradually decrease, and the generation of cold heat and heat also decreases. Therefore, after alternately repeating “generation of cold energy in the evaporator/condenser” and “generation of cold energy in the first adsorber”, the second adsorber 40 is regenerated. After generation, the second adsorbent of the second adsorber 40 may not reach the limit adsorption amount. Therefore, the adsorbate of the evaporator may be adsorbed by the second adsorbent before regeneration of the second adsorber. After cold heat is generated in the first adsorber 30, the on-off valve 60C is closed and the bypass on-off valve 60A is opened, so that the adsorbate (gas) in the evaporator/condenser 20 flows through the bypass pipe 50A to the second adsorber 40. and is adsorbed by the second adsorbent, and the reduced pressure in the evaporator/condenser 20 promotes evaporation of the adsorbate (liquid) to generate cold heat.
In this way, without passing from the second adsorber 40 to the first adsorber 30, the adsorbate in the evaporator/condenser 20 is evaporated and adsorbed by the adsorption capacity of the second adsorbent. Playback may be performed.

(Regeneration of second adsorber)
When the adsorption in the second adsorber 40 becomes saturated or when the adsorption force drops significantly, the on-off valve 60C is closed and the on-off valves 70D and 60A are opened to regenerate (desorb) the second adsorbent. At the same time, condensation of adsorbate is performed.
In the collector 10, the absorption of sunlight raises the temperature of the collector plate (selective absorption material 48) to a high temperature of 160° C. or higher, and the heat exchange fluid in the heat exchanger 12 is similarly heated. The second adsorption of the second adsorber 40 is performed by circulating the heat exchange fluid of the heat exchanger 12 heated to a high temperature by the heat collector 10 to the heat exchanger 42 of the second adsorber 40 through the connecting pipes 14A and 14B. The material is heated to high temperatures and the adsorbates are desorbed. Thereby, the second adsorbent of the second adsorber 40 is regenerated.

The adsorbate desorbed from the second adsorbent moves to the evaporator/condenser 20 through the bypass pipe 50A. The adsorbate that has moved from the second adsorber 40 to the evaporator/condenser 20 is cooled by supplying a room temperature heat exchange fluid to the heat exchanger 22 to perform heat exchange, and is condensed into a liquid state.

When the regeneration (desorption) of the second adsorber is finished, for example, if the pipes 14A and 14B are of a system in which a heat exchange fluid automatically circulates like a loop heat pipe, the on-off valve 70D is closed and the on-off valve 70C is opened to supply room temperature heat exchange fluid to the heat exchanger 42 for heat exchange. As a result, the heat of the high-temperature heat exchange fluid supplied from the heat exchanger 12 for the heat collector 10 to the heat exchanger 42 for the second adsorber 40 is taken out to the outside.
In addition, when the heat exchange fluid is forcibly circulated through the pipes 14A and 14B by a pump (not shown) or the like, turning off the pump or the like to stop the circulation of the heat exchange fluid allows the second adsorber 40 to Playback (detachment) may be terminated.
Alternatively, the regeneration (desorption) of the second adsorber 40 may be terminated by blocking the irradiation of sunlight to the heat collector 10 with a shutter (not shown) or the like.

The adsorption capacity of the second adsorber 40 is made larger than that of the first adsorber 30, and the above-mentioned "generation of cold energy in the evaporator/condenser" and "generation of cold energy in the first adsorber" are alternately repeated, After the cold is generated in the first adsorber, if necessary, the adsorbate in the evaporator/condenser 20 is adsorbed by the second adsorber 40 without passing through the first adsorber 30, so that the cold is continuously generated. can be taken out and used for air conditioners, refrigerators, freezers, etc.
When the adsorption in the second adsorber 40 becomes saturated and adsorption is no longer possible, or when the adsorption amount drops significantly, "regeneration of the second adsorber" is performed.

[Second embodiment]
Next, an adsorption heat pump system according to a second embodiment of the present disclosure will be described. In the second embodiment, the same components, members, etc. as in the first embodiment are denoted by the same reference numerals, and descriptions thereof are omitted.
FIG. 6 is a schematic diagram showing the configuration of the adsorption heat pump system of the second embodiment of the present disclosure. The adsorption heat pump system 200 shown in FIG. 6 includes an evaporator/condenser 20 serving as both an evaporator and a condenser, and a first adsorber 30, as in the first embodiment. The adsorption heat pump system 200 also includes a heat collector/second adsorber 50 in which a heat collector and a second adsorber are integrated. The evaporator/condenser 20, the first adsorber 30, and the heat collector/second adsorber 50 are provided with heat exchangers 22, 32, and 52, respectively, for exchanging heat with a heat medium fluid.

FIG. 7 is a schematic diagram showing the configuration of a heat collector/second adsorber 50 (an example of a solar collector) in the adsorption heat pump system of the second embodiment. FIG. 8 is a schematic diagram showing the positional relationship of the main parts of the heat collector/second adsorber 50 shown in FIG. 7 when viewed from the sunlight incident side.
The heat collector/second adsorber 50 includes, from the sunlight receiving side, a collector 61 such as a mirror or a lens, a restraining plate 66 made of PEEK (polyetheretherketone) or the like, a transparent window 56, a selective transmission As materials, silica airgel 58A, selective absorption material 48, honeycomb-structured second adsorbent 46, heat exchanger 42, silica airgel 58B as heat insulating material are arranged, and silica airgel 58C, 58D are also arranged as heat insulating materials around them. there is
The silica airgel 58A as a permselective material also serves as a heat insulator, and the silica airgel 58A, 58B, 58C, and 58D constitute a heat insulating container (heat insulating structure) 69. As shown in FIG. Silica aerogels 58C and 58D forming the side walls of the heat insulating container 69 are formed with holes 64 for passing adsorbates such as water vapor and holes 68C and 68D for passing the pipes 54A and 54B of the heat exchanger 52. . The selective absorbent material 48 , the second adsorbent 46 and the heat exchanger 42 are housed within such an insulated container 69 .

Furthermore, the heat-insulating container 69 is accommodated in a vacuum container 71 constituted by a window 56 and a container 62 made of PEEK or the like. The window 56 is positioned between the restraining plate 66 and the upper edge of the container 62 , and the restraining plate 66 is secured to the upper edge of the container 62 by bolts 54 . An O-ring 51 is interposed between the window 56 and the upper edge of the container 62 for sealing. A space 73 is provided between the adiabatic container 69 and the vacuum container 71 to which the adsorbate is supplied or removed through the connecting pipes 50C and 50A. The space 73 is evacuated by a vacuum pump (not shown).

By integrating the heat collector and the second adsorption device in this way, the vacuum vessel and the heat insulating structure can be shared, and the number of parts can be reduced to realize the simplification of the structure.
Further, in the first embodiment shown in FIG. 1, heat is transported from the heat collector 10 to the second adsorber 40 using the heat exchangers 12 and 42 and the heat transport medium (heat exchange fluid). In this case, heat is transmitted from the pipes 14A, 14B and the like to the air and other components, resulting in heat loss.
On the other hand, by integrating the heat collector and the second adsorber as in the second embodiment, there is no need to provide a heat transport mechanism between the heat collector and the second adsorber. Therefore, heat loss factors are reduced, and efficiency is expected to be improved accordingly.

The adsorption heat pump system 200 shown in FIG. 7 efficiently heats the selective absorption material 48 to high temperatures of 160° C. or higher, 200° C. or higher, or 300° C. or higher with a light collector 61, a double optical insulation vessel 69, and vacuum insulation. The temperature can be raised. In addition, since the selective absorption material 48, the second adsorbent 46 and the heat exchanger 42 are arranged in an overlapping state in the heat insulating container 69 capable of introducing and discharging the adsorbate, Adsorption/desorption of the adsorbate and heat exchange of the second adsorbent 46 can also be efficiently performed. Note that the positions of the second adsorbent 46 and the heat exchanger 42 may be reversed.

Next, a method of generating cold using the adsorption heat pump system 200 shown in FIG. 6 will be described.
9A-9C are schematic diagrams showing the flow of water vapor and heat exchange fluid in each operation mode of the adsorption heat pump system of the second embodiment using water W as the adsorbate. 9A to 9C show the on-off valve in the closed state depending on the situation, and the on-off valve in the open state is omitted. Also, the temperature in the figure is an example.

A mode: heat storage mode Sunlight is irradiated to the heat collection/second adsorption device 50, the temperature of the selective absorption material rises to 160°C or higher, and water vapor is desorbed from the second adsorption material. As shown in FIG. 9A, by opening the bypass opening/closing valve 60A, steam moves to the evaporator/condenser 20 through the bypass pipe 50A. The water vapor that has moved to the evaporator/condenser 20 is cooled by the room temperature heat exchange fluid supplied to the heat exchanger 22 to be condensed and stored as a liquid (water).

B mode: 1st stage output mode As shown in FIG. move and be absorbed. As water vapor is adsorbed by the first adsorber 30, the evaporation/condenser 20 is decompressed inside to accelerate the evaporation of water and generate cold heat. Cold heat generated in the evaporator/condenser 20 is taken out through the heat exchange fluid flowing through the heat exchanger 22 .

C Mode: Second Stage Output Mode As shown in FIG. 9C, the on-off valve 60B is closed and the on-off valve 60C is opened. Water vapor is desorbed from the first adsorber 30, moves to the heat collector/second adsorber 50, and is adsorbed by the second adsorbent. As a result, cold heat is generated by desorption in the first adsorber 30 . Cold heat generated in the heat collector/second adsorber 50 is taken out through the heat exchange fluid flowing through the heat exchanger 52 .

For example, each mode as described above is set to A mode during the day when the sun is out, and B→C→B→C . By setting it as such an operation mode, cold heat can be taken out alternately from the evaporator/condenser 20 and the first adsorber 30 to the outside, and cold water or cold air can be continuously supplied to the external equipment.
Also in the second embodiment, the B mode and C mode are repeated, and after the final C mode, the adsorbate in the evaporator/condenser 20 is collected through the bypass pipe 50A without passing through the first adsorber 30. It may be transferred to the heat/second adsorber 50 and adsorbed to generate cold heat in the evaporator/condenser 20, and then the second adsorbent may be regenerated in the A mode.

<Comparison between single-stage adsorption heat pump system and multi-stage adsorption heat pump system>
Al-MOF was used as the first adsorbent in the first adsorber 30, and zeolite 13X was used as the adsorbent in the second adsorber 40, respectively, in order to compare the cold generation capacity of the single-stage adsorption heat pump system and the multi-stage adsorption heat pump system. , performed a simulation.

(Simulation using a single-stage adsorption heat pump system)
FIG. 10 is a schematic diagram showing the configuration of a single-stage adsorption heat pump system used for simulating temperature changes in the evaporator and adsorber. In a configuration that combines a heat collector and an adsorber, a contact heat resistance simulation layer is placed as a thermal resistance between the adsorbent and the heat exchanger, and simulations are performed under the conditions where water vapor in the evaporator/condenser is adsorbed by the adsorbent. gone. FIG. 11 is a diagram showing temperature changes of the evaporator and the adsorber simulated in the single-stage adsorption heat pump system. At the beginning of operation, cold heat was generated in the evaporator and hot heat was generated in the adsorber, resulting in a large temperature difference. However, the temperature difference decreased over time, and the temperature of the evaporator and the temperature of the absorber became almost the same level. . At first, since the adsorbent is empty, a large adsorption speed and evaporation speed occur, accompanied by temperature rise and temperature drop. Since the adsorbent gradually approaches the equilibrium adsorption amount, the adsorption speed and evaporation speed decrease, and the heat exchanger is assumed to be kept at a constant temperature by constantly flowing heat exchange fluid at room temperature. It is thought that the heat generation and the cold heat are no longer generated, and both reach the temperature of the heat exchanger.

(Simulation by multi-stage adsorption heat pump system)
FIG. 12 is a schematic diagram showing the configuration of a multistage adsorption heat pump system used for simulating temperature changes in the evaporator and adsorber. The structure is equipped with an evaporator/condenser, a first adsorber, and a heat collector/second adsorber, and the heat resistance between the adsorbent and the heat exchanger is A contact thermal resistance simulating layer was arranged. Al-MOF was used as the first adsorbent of the first adsorber, and zeolite 13X was used as the second adsorbent of the second adsorber. FIG. 13 is a schematic diagram showing the flow of water vapor in a simulation using the multistage adsorption heat pump system configured as shown in FIG. As shown in FIG. 13, water (adsorbate) moves from the evaporator/condenser to the first adsorber and is adsorbed by the first adsorbent. The simulation was performed under the condition that the mode of moving to and being adsorbed by the second adsorbent is alternately repeated.
FIG. 14 is a diagram showing temperature changes of the evaporator and the adsorber simulated by the multistage adsorption heat pump system having the configuration shown in FIG. 1 is the temperature of the evaporator/condenser in B mode, and 2 is the temperature of the first adsorber in B mode. 3 indicates the temperature of the first adsorber in C mode, and 4 indicates the temperature of the second adsorber in C mode. As shown in FIG. 14, by alternately repeating the B mode and the C mode, it is possible to extract cold energy with high efficiency.

FIG. 15 is a graph comparing the cooling output calculated based on each simulation result. The cooling capacity of the multi-stage adsorption heat pump system is more than double the cooling capacity of the single-stage adsorption heat pump system, demonstrating high efficiency.

Although the adsorption heat pump systems of the first embodiment and the second embodiment have been described above, the adsorption heat pump system according to the present disclosure is not limited to these embodiments.
For example, in the first embodiment and the second embodiment, an evaporator/condenser serving as both an evaporator and a condenser and a bypass pipe are provided. They may be provided separately. For example, a condenser is placed between the second adsorber and the evaporator, the adsorbate desorbed from the second adsorber is transferred to the condenser, cooled by the heat exchanger and condensed, and then transferred to the evaporator. You may let

Also, the adsorbate of the second adsorber may be adsorbed on the first adsorber when the second adsorber is regenerated.
In addition, the solar collector is not limited to a combination of a selective transmission material and a selective absorption material as shown in FIG. 2 or FIG. It is good also as a heat collector which can heat up to 160 degreeC or more.

Also, a plurality of first adsorbers may be provided and arranged in parallel with respect to the connection direction of the evaporator and the second adsorber. It is possible to perform different treatments with a plurality of first adsorbers arranged in parallel in this manner. For example, a particular first adsorber may adsorb an evaporator adsorbate, while other first adsorbers may desorb and adsorb in a second adsorber.

10, 10A Solar collectors 12, 22, 32, 42, 52 Heat exchanger 20 Evaporator/condenser 30 First adsorber 40 Second adsorber 46 Second adsorbent 48 Selective absorption material (an example of a heat collector plate )
50 Heat collector/second adsorber 50A Bypass pipe 56 Window 58 Selectively permeable material 58A, 58B, 58C, 58D Silica airgel 60A Bypass on-off valve 60B On-off valve 60C On-off valve 61 Light collector 62 Container 64 Hole 66 Control plate 68C, 68D Hole 69 Heat insulation container 70A On-off valve 70B On-off valve 70C On-off valve 70D On-off valve 71 Vacuum container 73 Space 90 Housing 92 Heat insulating material 94 Heat transfer part 96 Heat exchange fluid contact part 100 Adsorption heat pump system 200 Adsorption heat pump system W Water ( an example of an adsorbate)

Claims (9)

an evaporator in which the adsorbate evaporates to produce cold;
a first adsorber including a first adsorbent that adsorbs the adsorbate evaporated in the evaporator;
a second adsorber including a second adsorbent that adsorbs the adsorbate desorbed from the first adsorbent;
A heating source for heating the second adsorber, comprising a heat collecting plate that absorbs sunlight and raises the temperature, a collector that collects the sunlight on the heat collecting plate, and a heat source from the heat collecting plate a solar heat collector that includes a temperature-increasing auxiliary means for at least one of a heat insulating material that insulates radiant heat, and is capable of increasing the temperature of the heat collecting plate to 160° C. or higher by the sunlight;
a bypass pipe that bypasses the first adsorber and connects the evaporator and the second adsorber;
using an adsorption heat pump system comprising
Adsorbing the adsorbate with the first adsorbent and evaporating the adsorbate with the evaporator to generate cold heat;
a step of desorbing the adsorbate from the first adsorbent by adsorbing the adsorbate with the second adsorbent to generate cold heat;
After repeating multiple times alternately,
a step of regenerating the second adsorbent by heating the second adsorbent with the solar heat collector to desorb the adsorbate;
A step of adsorbing the adsorbate introduced from the evaporator into the second adsorber through the bypass pipe with the second adsorbent before the step of regenerating the second adsorbent;
A method of generating cold, comprising: 2. The method of claim 1, wherein the adsorption capacity of the second adsorber is greater than the adsorption capacity of the first adsorber. 3. The evaporator according to claim 1, wherein the evaporator also serves as a condenser for condensing the adsorbate desorbed from the second adsorbent and introduced into the evaporator through the bypass pipe. Cold generation method . A group in which the adsorption heat pump system comprises a heat exchanger that performs heat exchange with the evaporator, a heat exchanger that performs heat exchange with the first adsorbent, and a heat exchanger that performs heat exchange with the second adsorbent. The cold heat generation method according to any one of claims 1 to 3, comprising at least one heat exchanger selected from. 1 to claim, wherein the solar heat collector heats the second adsorbent via at least one heat transfer means selected from the group consisting of a heat exchanger, a heat exchange fluid, a liquid pump and a heat pipe. Item 5. The method for generating cold heat according to any one of Item 4. The cold heat generation method according to any one of claims 1 to 5, wherein the heat collecting plate and the second adsorbent are arranged in the same heat insulating structure including the heat insulating material. The solar heat collector includes, as the heat insulating material, a selectively transmitting material that selectively transmits the sunlight to the heat collecting plate, and as the heat collecting plate, the sun transmitted through the selectively transmitting material. A method of generating cold heat according to any one of claims 1 to 6, comprising a selective absorption material that selectively absorbs light. The selective transmission material has an average transmittance of 80% or more in a sunlight region with a wavelength of 0.3 μm to 2.5 μm and a thermal conductivity of 0.5 W/m/K or less,
The selective absorption material has an average absorptivity of 80% or more in the sunlight region, and an average transmittance of 20% or more in the radiation region with a wavelength of more than 2.5 μm to 20 μm. 8. The cold heat generation method according to claim 7, wherein the emissivity is 60% or less. The first adsorbent is at least one selected from the group consisting of mesoporous silica, Al-MOF and Zr-MOF, and the second adsorbent is zeolite. The method for generating cold heat as described.

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