JPH05322361A - Adsorption type cooling system - Google Patents

Abstract

PURPOSE:To shorten a time required for heating and regenerating steps and to improve an operating efficiency of an entire system by using a microwave heater as means for heating an adsorption unit at the time of the step of regenerating to separate adsorbing medium in the unit and return it into a cooling vessel. CONSTITUTION:An adsorption type cooling system comprises a pair of adsorption units 20, 21 each containing an adsorbing material, a cooling vessel 22 coupled thereto, a condenser 23, a heat exchanger 24, etc. In an adsorbing step, one unit is cooled, and the medium in the vessel 22 is adsorbed into the unit. On the other hand, in a regenerating step, the other unit is superheated to return the medium in the unit to the vessel 22. In the above structure, a microwave heater for induction-heating is used as means for heating the unit. The heater has an oscillator 29, a power source 30 and a waveguide 31. Thus, a time required for the heating and regenerating steps is shortened to improve an operating efficiency of the entire system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adsorption type cooling system applicable to an air conditioner for a vehicle, a residential building, or a ship, a cooling device for a container for transporting food or medicines requiring refrigeration, and the like. is there.

[0002]

2. Description of the Related Art Conventionally, as a cooling system used for an air conditioner, a refrigerating device, etc., a heat pump type has been generally known, but recently, an adsorption type cooling system using an adsorbent made of zeolite or the like. Is proposed.
As a conventional technique related to this, for example, Japanese Patent Laid-Open No.
There is one described in Japanese Patent Publication No. 2-5060.

FIG. 5 shows the basic principle of an adsorption type cooling system, in which an adsorber 1 and a cooling container 2 are connected to each other and an opening / closing valve 3 is provided.
Is a single adsorption cooling system connected by a conduit 4 having An adsorbent 1a made of zeolite or the like is accommodated in the adsorber 1, and a heat exchange pipe 5 for heating or cooling is in contact with the adsorbent 1a. Water as an adsorption medium is contained in the cooling container 2, and a cooling pipe 6 through which air to be cooled flows is thermally contacted with the water, and the adsorber 1, the pipe line 4 and the inside of the cooling container 2 are in contact with each other. Is in a vacuum. In addition, a condenser 7 that exchanges heat with the outside air is provided on the side of the cooling container 2 of the pipeline 4. With this cooling system,
When the opening / closing valve 3 of the pipe line 4 is opened, the water in the cooling container 2 is evaporated into water vapor by the adsorption action of the adsorbent 1a as shown in FIG. Adsorbent 1
Adsorbed by a. As a result, the latent heat when the water in the cooling container 2 evaporates is absorbed from the cooling container 2 side, so that the temperature in the cooling container 2 decreases and the air in the cooling pipe 6 is cooled. Such an operation is called an adsorption process. Next, the operation of returning the water adsorbed by the adsorbent 1a to the cooling container 2 is performed.
That is, as shown in FIG. 5 (b), the adsorbent 1a is heated by circulating high-temperature air from the external heat source through the heat exchange pipe 5 to separate the water adsorbed by the adsorbent 1a.
As a result, the moisture that has become steam becomes water in the condenser 7 through the conduit 4 and is collected in the cooling container 2. Such an operation is called a reproduction process. In this case, the adsorption means a state where water molecules are held between the molecules of the adsorbent, and by heating the adsorbent in this state, water is separated from the adsorbent and regenerated.

However, in the above-described single adsorption type cooling system, since the adsorption process and the regeneration process must be alternately performed in the same system, continuous cooling cannot be performed. Therefore, as shown in FIG. 6, a dual adsorption cooling system having two adsorbers 8 and 9 has been proposed. The adsorbers 8 and 9 are open / close valves 10 and 1, respectively.
One cooling container 13 by the pipe lines 12 and 13 having one
The cooling pipe 14 similar to the above is in thermal contact with the water in the cooling container 13. In addition, each adsorber 8,
The adsorbents 8a and 9a in 9 are respectively provided with the heat exchange pipe 1
5 and 16 are in thermal contact with each other, and condensers 17 and 18 are provided in the pipe lines 12 and 13, respectively. In this cooling system, for example, the adsorption process is performed in one of the adsorbers 8 while the regeneration process is performed in the other adsorber 9. Then, when the adsorbers 8 and 9 have completed their respective strokes, a switching operation is performed so as to perform the reverse operation. At that time, since the adsorber 9 that has completed the regeneration process is at a high temperature, air at a low temperature or room temperature is circulated through the heat exchange pipe 16 to cool the adsorbent 9a. By repeating such an operation periodically, it is possible to perform continuous cooling.

[0005]

In the double adsorption cooling system, the heat exchange pipes 15 and 1 are connected.
Since the electric heater and the exhaust gas of the engine are used as the heat source of 6, the adsorbent 8a (9
It took a long time for the heating of a), that is, the regeneration process. Therefore, there is a problem that the switching cycle of each process becomes long and the operating efficiency of the entire system is reduced.

The present invention has been made in view of the above problems, and an object of the present invention is to provide an adsorption cooling system capable of shortening the time required for the regeneration process and improving the operating efficiency of the entire system. To provide.

[0007]

To achieve the above object, the present invention selectively cools a pair of adsorbers containing an adsorbent, a cooling container connected to each adsorber, and each adsorber. Cooling means and a heating means for selectively heating each adsorber, and an adsorption step for adsorbing the adsorption medium in the cooling container into the adsorber by cooling one of the adsorbers, and another In an adsorption type cooling system in which the adsorption medium in the adsorber is separated by heating the adsorber and returned to the inside of the cooling vessel, the adsorbing type cooling system alternately performs the regeneration process in each adsorber. It is composed of a microwave heating device for dielectric heating.

[0008]

According to the adsorption cooling system of the present invention, since the adsorbent of the adsorber is dielectrically heated by the microwave heating device, the adsorbent is uniformly and quickly heated, and the time required for the regeneration process is shortened. It

[0009]

1 to 3 show one embodiment of the present invention, showing a vehicle air conditioner to which the adsorption cooling system of the present invention is applied. In the figure, 20 and 21 are adsorbents 20,
21a is a first and second adsorber, 22 is a cooling container containing water as an adsorption medium, 23 is a condenser, and 24 is a heat exchanger inside the vehicle.

Each of the adsorbers 20 and 21 accommodates an adsorbent made of zeolite or the like, and they are arranged at intervals. An outside air introduction path 26 having a blower 25 is connected between the adsorbers 20, 21 via a condenser 23, and the adsorbers 20, 2 are provided on the opposite side of the adsorbers 20, 21.
Exhaust air ducts 27 for discharging the air passing through 1 are connected to each other. A flap 28 for switching the flow direction of air is provided between the adsorbers 20 and 21 so that the air in the outside air introduction passage 26 can be selectively supplied to the adsorbers 20 and 21. On the other hand, each of the adsorbers 20 and 21 is adapted to be dielectrically heated by a microwave oscillator 29 (hereinafter referred to as oscillator 29) including a magnetron or the like. That is, the oscillator 29 is driven by a power supply 30 such as a high-voltage transformer, and is connected to the adsorbers 20 and 21 via a waveguide 31, and the switching device 31 a of the waveguide 31 allows the microwaves to be adsorbed to the adsorbers 20 and 21. Can be transmitted as an alternative. Therefore, these oscillators 29,
The microwave heating device is configured by the power source 30 and the waveguide 31. The frequency of the microwave generated by the oscillator 29 is considered to be appropriate for heating the adsorbent 24.
It is set to 50 MHz. In addition, each adsorber 20, 2
Both ends of 1 are wire mesh 31 for preventing microwave leakage
covered by b.

The cooling container 22 is connected to the first adsorber 20 via the first vapor outward path 32 and is connected to the second adsorber 21 via the second vapor outward path 33, respectively.
On-off valves V1 and V2 are provided at 3. In this embodiment, water is used as the adsorption medium contained in the cooling container 22, but other liquid such as alcohol may be used. Further, the respective vapor outward paths 32 and 33 can communicate with each other by a bypass passage 34 which is branched and connected to each other, and the bypass passage 34 has two opening / closing valves V3 and V3.
4 are provided. Further, one end of a steam return path 35 is branched and connected in the middle of each of the opening / closing valves V3 and V4 in the bypass path 34, and an opening / closing valve V5 is provided in the steam return path 35. The bypass passage 34 also functionally constitutes a part of the steam return passage 35. Further, the other end of the vapor return path 35 is connected to the condenser 23, and the condenser 23 is connected to the cooling container 22 via a small-diameter condensation passage 36. In the flow cross section of each passage, the cross-sectional area of the steam return path 35 and the bypass passage 34 is about 50% of the cross-sectional area of the steam outward path 32 (33), and the cross-sectional area of the condensation passage 36 is the steam return path 35 and the bypass passage 34. It is set to about 0.6% of the cross-sectional area.

The heat exchanger 24 is connected to a cooling pipe 37 which is in thermal contact with the water in the cooling container 22.
A pump 38 provided in the
A heat medium such as brine is circulated. Further, the heat exchanger 24 is arranged between the intake air passage 39 and the blowout air passage 40 for the air in the vehicle, and the blowout air passage 40 branches into a plurality of air outlets 41 provided in a driver's seat, a passenger seat, etc., Each outlet 41 is provided with a louver 42.

In the above structure, for example, the first adsorber 2
When the adsorption process is performed at 0 and the regeneration process is performed at the second adsorber 21, the flap 28 and the switching device 31a are set to the positions shown by the solid line in the figure, and the outside air introduction path 26 is set to the first adsorber 20 and the waveguide. 31 is connected to the second adsorber 21. As a result, the low-temperature air (outside air) that has flowed into the outside air introduction passage 26 is fed to the first adsorber 20 as indicated by the solid line arrow in the drawing, and
The adsorber 20 is cooled. At this time, the condenser 23 in the outside air introducing passage 26 is also cooled by the outside air taken in at the same time. On the other hand, the microwave generated by the oscillator 29 is generated by the waveguide 3
1 to the second adsorber 21 and the second adsorber 21
The adsorbent therein is dielectrically heated. The heating in this case means that the adsorbent is dielectrically heated by the microwave guided to the inner surface of the adsorber, and is different from the case where the microwave is irradiated from the outside of the adsorber. In addition, each adsorber 20, 21
In the case of performing the process reverse to that described above, the first adsorber 20 is heated and the second adsorber 21 is cooled by switching the flap 28 and the switch 31a to the positions shown by the alternate long and short dash line in the figure.

Next, referring to the principle diagram of FIG. 2 and the P-1 / T diagram of FIG. 3, the operation of the adsorption cooling system in this embodiment, that is, the operation between the adsorbers 20 and 21 and the cooling container 22 will be described. Explain. Note that, in FIG. 2, each component is illustrated in a shape slightly different from that in FIG. 1 for the sake of easy description. Also,
In FIG. 3, P is water vapor pressure, T is temperature, and the numerical values shown in the figure are examples.

That is, the adsorption process in the first adsorber 20
When performing the regeneration process in the adsorber 21, first, the opening / closing valves V1, V2, V3, V4 are closed and the opening / closing valve V5 is opened. As a result, the temperature inside the first adsorber 20 has a water content of 6%.
Is cooled to 150 ° C. on the water equivalent line (C ′ → D), and the temperature in the second adsorber 21 is 1 on the water equivalent line having a water content of 22%.
It is heated to 50 ° C. (A ′ → B). At this time, the water vapor pressure P1 in the first adsorber 20 is 10 mbar, and the water vapor pressure P2 in the second adsorber 21 is 450 mbar. Incidentally, P3 is the average value of P1 and P2. Next, the opening / closing valves V1, V4, V5 are opened with the opening / closing valves V2, V3 kept closed. As a result, the water in the cooling container 22 evaporates under the pressure of 10 mbar and the first adsorber 2 passes through the first vapor outward path 32.
It is adsorbed by the adsorbent 20a of 0. At that time, the heat in the cooling container 22 is taken by the latent heat of vaporization of water. And the first
By continuing to cool the inside of the adsorber 20, the cooling container 22
Water in the first adsorber 20 is sequentially adsorbed by the adsorbent 20a.
The inside is finally cooled to 70 ° C. (D → A). on the other hand,
The inside of the second adsorber 21 is heated to 280 ° C. under a pressure of 450 mbar (B → C), the water adsorbed on the adsorbent 21a of the second adsorber 21 is separated and regenerated, and the bypass passage 3
4 and the steam return path 35 to flow into the condenser 23. Then, the water condensed in the condenser 23 is returned to the inside of the cooling container 22 through the condensation passage 36. Such operation is from 1 minute to 1
It takes place on a daily cycle. Further, the reason why the flow cross-sectional areas of the vapor outward paths 32 and 33, the vapor return path 35, and the condensing passage 36 become smaller in order is that the density of water vapor becomes larger in this order (a liquid in the condensing passage 36), and in particular the condensation In the passage 36, it is desirable that the flow rate be almost the same as the amount of water evaporated from the cooling container 22.

At the end of the above-mentioned process, the inside of the second adsorber 21 which has undergone the regeneration process has a high temperature of about 280 ° C., and the first adsorber 20 which has completed the adsorption process has a low temperature of about 70 ° C. Has become. Here, before switching the adsorbers 20 and 21 to the reverse process to the above-described process, the following intermediate process is performed to reuse the difference in enthalpy between the adsorbers 20 and 21 so as not to generate waste heat. That is, the open / close valve V
1, V2 and V5 are closed, only the opening / closing valves V3 and V4 of the bypass passage 34 are opened, and the adsorbers 20 and 21 are closed.
Are communicated with each other without the cooling container 22. As a result, a part of the heat in the second adsorber 21 moves into the first adsorber 20, the temperature in the first adsorber 20 that is going to perform the regeneration process next rises, and the adsorption process is performed. The temperature in the intended second adsorber 21 decreases. This intermediate step is performed only for a period of about 1% to 5% of the switching cycle of the adsorption / regeneration step. Although the intermediate stroke cannot be plotted in the diagram of FIG. 3, it can be said that it is part of the adsorption / regeneration stroke.

In this way, the inside of the cooling container 22 is continuously cooled by periodically repeating the adsorption process → intermediate process → regeneration process → intermediate process → adsorption process in each adsorber 20, 21. Incidentally, FIG. 4 shows the open / closed state of the valves V1, V2, V3, V4 and V5 in the respective strokes.

Now, returning to FIG. 1, the air conditioning operation inside the vehicle will be described. That is, as the inside of the cooling container 22 is cooled by the cooling system, the cooling pipe 37 in the cooling container 22 is cooled, and the heat medium in the cooling pipe 37 which has become low temperature flows into the heat exchanger 24. On the other hand, the in-vehicle air taken into the intake air passage 39 is fed to the heat exchanger 24 and cooled by the heat exchanger 24. Then, the cooled air is blown out into the vehicle from each air outlet 41 through the blowout air passage 40.

As described above, according to the adsorption cooling system of the present embodiment, the microwave heating device (oscillator) for dielectrically heating the adsorbent 20a (21a) is used as a means for heating the adsorber 20 (21) in the regeneration process. 29, power supply 30, waveguide 3
Since 1) is used, the adsorbent 20a (21a) can be rapidly heated without unevenness, and the time required for the regeneration process can be significantly shortened.

[0020]

As described above, according to the adsorption cooling system of the present invention, the time required for the regeneration process can be greatly shortened, so that the switching cycle of each process is shortened and the operation of the entire system is reduced. The efficiency can be significantly improved.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a vehicle air conditioner including an adsorption cooling system according to an embodiment of the present invention.

[Fig.2] Principle of adsorption cooling system

FIG. 3 P showing the adsorption / regeneration process of an adsorption cooling system
-1 / T diagram

FIG. 4 is a diagram showing an open / closed state of each open / close valve.

FIG. 5: Principle diagram of a single adsorption cooling system showing a conventional example

FIG. 6 is a principle diagram of a dual adsorption cooling system showing a conventional example.

[Explanation of symbols]

20 ... 1st adsorption device, 21 ... 2nd adsorption device, 20a, 21a
... Adsorbent, 22 ... Cooling container, 29 ... Microwave oscillator,
30 ... Power source, 31 ... Waveguide, V1, V2, V3, V4
V5 ... Open / close valve.

Claims (1)

[Claims] 1. A pair of adsorbers accommodating an adsorbent, a cooling container connected to each adsorber, cooling means for selectively cooling each adsorber, and each adsorber being heated selectively. An adsorbing step of adsorbing the adsorption medium in the cooling container into the adsorber by cooling one of the adsorbers,
In an adsorption type cooling system in which the adsorption medium in the adsorber is separated by heating the other adsorber and the regeneration process of returning the adsorbent to the inside of the cooling vessel is alternately performed in each adsorber, the heating means of the adsorber An adsorption cooling system comprising a microwave heating device for dielectrically heating an adsorbent.