JPH05203284A - Absorption chiller / heater - Google Patents

Abstract

(57) [Summary] [Purpose] To provide an absorption chiller-heater that simplifies the separation of high-purity refrigerant and downsizes it. [Structure] The absorption chiller-heater 1 includes an absorber 2, a solution pump 3, a heat exchanger 5, a separation membrane 6, a regenerator 7, a burner 8, a condenser 10, a capillary 11, and an evaporator 12. The regenerator 7 heats the dilute solution containing the refrigerant by the heating source (burner 8) and selectively separates the refrigerant vapor from the absorbing solution by the action of the separation membrane 6 to form an absorbing concentrated solution. The absorber 2 guides the concentrated solution from the regenerator 7 to absorb the refrigerant vapor. The diluted solution that has absorbed the refrigerant vapor in the absorber 2 is supplied to the regenerator 7 via the heat exchanger 5 by means (solution pump 3) for guiding the regenerator 7. Condenser 10
Cools the refrigerant vapor generated in the regenerator 7 into condensed refrigerant. The condensed refrigerant in the condenser 10 evaporates in the evaporator 12. The refrigerant vapor evaporated in the evaporator 12 is absorbed by the absorption concentrated solution in the absorber 2 to become a dilute solution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of an absorption chiller / heater, and more particularly to an absorption chiller / heater having a simplified refrigerant separation.

[0002]

2. Description of the Related Art An absorption chiller-heater of this type is known as an apparatus in which a refrigerant cycle and an absorption solution cycle coexist. In this refrigerant cycle, a refrigerant liquid is evaporated in an evaporator into a refrigerant vapor, and this refrigerant vapor is absorbed in a concentrated concentrated solution at a low pressure in an absorber to form a dilute solution, and this dilute solution is pumped into a regenerator having a high pressure. The heat in the solution is given from the outside to evaporate the refrigerant in the solution again and send it to the condenser. In this condenser, the refrigerant vapor is cooled to become the refrigerant liquid, and the refrigerant liquid is guided to the evaporator again. It is a cycle. Further, in the absorption solution cycle, the absorbent dilute solution generated in the absorber is sent to a regenerator by a pump, and heat energy is externally applied in this regenerator to evaporate the refrigerant in the solution to form an absorption concentrated solution, This is a cycle in which the concentrated absorption solution is guided to the absorber again.

By the way, as the absorption solution for the absorption chiller / heater, water-lithium bromide type and ammonia-water type are generally used, and chlorofluorocarbon-ether type and the like are also considered. Among these absorbing solutions, water-lithium bromide-based absorbents are solid at room temperature, and have high viscosity and crystallographic problems at high concentrations, and thus the usable concentration range is limited. The ammonia-water system and the chlorofluorocarbon-ether system are both gas and liquid at room temperature for both the refrigerant and the absorbent, and the cycle can be set in a high concentration range.

However, these ammonia-water systems,
In the CFC-ether system, the difference in boiling point between the refrigerant and the absorbent is much smaller than that in the water-lithium bromide system, so a rectifier and a dephlegmator are provided in the main body of the absorption chiller / heater.

FIG. 3 is a system diagram showing the construction of the above-mentioned ammonia-water type and freon-ether type absorption chiller-heater.

In the absorption chiller / heater 101, the absorber 10
The dilute solution of No. 2 is sucked by the solution pump 103, heated by the partial condenser 104, heat-exchanged by the heat exchanger 105, and then supplied to the rectifier 106. The solution rectified by the rectifier 106 is supplied to the regenerator 107. Regenerator 107
At the concentrated concentrated solution, which is heated by the burner 108 to evaporate and condense the refrigerant vapor, is heat-exchanged with the dilute solution by the heat exchanger 105 and supplied to the inside of the absorber 102. The concentrated absorption solution supplied to the inside of the absorber 102 absorbs the refrigerant vapor, and the absorption heat generated at this time is removed by the cooling water 109. Absorber 102-solution pump 103-divider 104
The solution flowing through the path of heat exchanger 105-rectifier 106-regenerator 107-heat exchanger 105-absorber 102 will form an absorption solution cycle. Further, the refrigerant vapor generated in the regenerator 107 is guided to the condenser 110, where it is cooled by the cooling water 109 and condensed and liquefied. The refrigerant liquid liquefied in the condenser 110 is decompressed by the capillary 111 which is a pressure reducing valve, guided to the evaporator 112, sprayed to the evaporator heat transfer tube 113 and evaporated, and evaporated from the water flowing to the evaporator heat transfer tube 113. Take away the latent heat. As a result, the cold water 11 flows from the evaporator heat transfer tube 113.
4 can be obtained, and the cold water 114 can be used for cooling or the like. The absorber 102-solution pump 103-
Separator 104-Rectifier 106-Regenerator 107-Condenser 1
10-Capillary 111-Evaporator 112-Absorber 10
A refrigerant cycle is formed by the refrigerant flowing through the two paths. The circuit configuration for obtaining hot water is omitted.

According to the absorption chiller-heater 101 described above, the cold water 114 can be obtained by the refrigerant cycle and the absorption solution cycle.

[0008]

According to the absorption chiller-heater described above, the water-lithium bromide system has a problem of high viscosity and crystal breakage, whereas the ammonia-water system and the freon-ether system are refrigerants.・ Absorbent is a gas or liquid at room temperature, so there is an advantage that the cycle can be set in a high concentration range, but in the ammonia-water system and CFC-ether system, the difference in boiling point between the refrigerant and the absorbent is Is considerably smaller than that of the water-lithium bromide system, there is a drawback that the absorption chiller / heater main body requires a rectifier and a dephlegmator in order to increase the purity of the refrigerant, resulting in an increase in the size of the device. It was

An object of the present invention is to provide an absorption chiller-heater which eliminates the above-mentioned drawbacks, simplifies high-purity refrigerant separation, and downsizes the apparatus.

[0010]

In order to achieve the above object, the absorption chiller-heater of the present invention comprises a regenerator for heating a dilute solution containing a refrigerant by a heating source to produce a refrigerant vapor and an absorption concentrated solution. , An absorber that guides the concentrated solution from the regenerator to absorb the refrigerant vapor, a means that guides the dilute solution that has absorbed the refrigerant vapor in the absorber to the regenerator, and the refrigerant vapor generated in the regenerator. A condenser that cools to a condensed refrigerant and a condensed refrigerant in the condenser are introduced, and the condensed refrigerant is sprayed on an evaporator heat transfer tube to evaporate and become a refrigerant vapor, and the refrigerant vapor is supplied to an absorber. In an absorption chiller-heater equipped with
In the regenerator, a separation membrane that comes into contact with the absorption concentrated solution and separates only the refrigerant vapor from the absorption concentrated solution is provided.

Further, it is preferable that the separation membrane is arranged at a position in contact with the absorbing solution in the regenerator. Furthermore, the separation membrane has a structure in which the membrane is formed into a hollow fiber shape, the absorbent solution is brought into contact with one surface of the hollow fiber shape, and the refrigerant vapor is taken out from the other surface of the hollow fiber shape, thereby providing a contact area with the absorbent solution. Can be increased.

[0012]

In the present invention, the separation membrane is provided in the regenerator, the absorbing solution is brought into contact with the separation membrane, and the refrigerant vapor is selectively taken out by the separation membrane, whereby the rectifier and the dephlegmator are omitted. It was done.

[0013]

The present invention will be described below with reference to the illustrated embodiments.

FIG. 1 is a system diagram of an embodiment of an absorption chiller-heater of the present invention, which uses an ammonia-water system and a fluorocarbon-ether system.

In the absorption chiller-heater 1 shown in FIG. 1, the diluted solution in the absorber 2 is sucked by the solution pump 3 and exchanged heat with the heat exchanger 5, and then supplied to the regenerator 7 having the separation membrane 6 built therein. To be done. Separation membrane 6 which is a polymer membrane provided in the regenerator 7.
Uses the principle of the pervaporation method, and can selectively separate only the refrigerant (ammonia, chlorofluorocarbon) from the ammonia-water system and the chlorofluorocarbon-ether system. The concentrated liquid, which is heated by the burner 8 to evaporate water vapor and the refrigerant is selectively separated by the separation membrane 6 to be concentrated, exchanges heat with the dilute solution in the heat exchanger 5 and is supplied to the inside of the absorber 2. To be done. The concentrated liquid supplied to the inside of the absorber 2 absorbs the refrigerant vapor again, and the absorption heat generated at this time is removed by the cooling water 9. The solution flowing through the path of the absorber 2-solution pump 3-heat exchanger 5-regenerator 7-heat exchanger 5-absorber 2 described above forms an absorption solution cycle. Further, the refrigerant vapor generated in the regenerator 7 due to the heating of the burner 8 and the action of the separation membrane 6 is guided to the condenser 10, and is cooled by the cooling water 9 in the condenser 10 to be condensed and liquefied. The refrigerant liquid liquefied in the condenser 10 is decompressed by the capillary 11 and is evaporated.
Is guided to the evaporator heat transfer tube 13 to be sprayed and evaporated, and the latent heat of evaporation is taken from the water flowing in the evaporator heat transfer tube 13. As a result, the water flowing through the evaporator heat transfer tube 13 is cooled and the cold water 14
Can be obtained. Further, the refrigerant vapor evaporated in the evaporator 12 is guided to the absorber 2 and is again absorbed in the absorption concentrated solution. In addition, the above-mentioned absorber 2-solution pump 3-regenerator 7
-Separation membrane 6-Condenser 10-Capillary 11-Evaporator 1
2-Refrigerant cycle is formed by the refrigerant flowing through the path of the absorber 2.

Next, the separation membrane 6 provided inside the regenerator 7 will be described.

In the above-mentioned embodiment, a pair having a close boiling point, such as ammonia-water type and freon-ether type, is used as the absorbing solution. Absorption chiller / heater 1 using such an absorbing liquid
In the above, using the separation membrane 6 described above and utilizing the principle of the pervaporation method, an ammonia-water system, a flon-
Refrigerants such as ammonia and freon are selectively separated from the ether system. The pervaporation method is a method in which a dilute solution is caused to flow on one side of the separation membrane 6 and the opposite side of the separation membrane 6 is depressurized (a pressure difference is provided between the dilute solution side) and the refrigerant can be taken out to the opposite side as vapor. is there. Comparing the pervaporation method with the reverse osmosis method which is an existing membrane separation technology, the flow rate of the refrigerant vapor is about 100 times or more higher in the pervaporation method.

Here, when the fluorocarbon-ether type absorption solution pair is to be separated, the molecular size of fluorocarbon and ether is 5 times to 10 times, which is quite different. It is recommended to use a quality membrane. Permeation of ether can be prevented by the pore size of this etherphobic porous membrane. This porous film is preferably a film of tetrafluoroethylene resin, for example.

In the case of ammonia-water system, the separation membrane 6
As the film, a film that selectively permeates only ammonia is used. That is, as the separation membrane 6, it is preferable to use a membrane in which ammonia has a higher solubility than water. When an ammonia selective permeable membrane is used as the separation membrane 6, the types of the ammonia selective permeable membrane include a sulfolane-added membrane, an ethylene glycol-added membrane, a sulfoxide group-containing polymer membrane, an ethylenediamine-containing polymer membrane, and a carbonate. Examples thereof include an ion-containing liquid film.

The separation film 6 may be a thin film formed on a base film or a substrate. This base film can be manufactured by a melt extrusion method such as a T-die method or an inflation method. The thin film formed on the substrate is a chemical vapor deposition method (CVP method (Chemical
Vapor Deposition)) or physical vapor deposition (PV
It can be manufactured by the D method (Phsical Vapor Deposition). The PVD method includes, for example, a vacuum vapor deposition method, a sputtering method, an ion plating method and the like. Next, another embodiment of the present invention will be described.

When separating the refrigerant vapor from the concentrated absorption solution, the permeation coefficient, the permeation rate, and the separation coefficient affect.
The higher these values are, the more desirable. Further, since the amount of refrigerant vapor generated by the separation membrane is small, it is necessary to increase the contact area between the absorbing solution and the separation membrane. Therefore, in another embodiment, as shown in FIG. 2, a hollow fiber is used.
The contact area is increased as the strip-shaped separation film 6a. Now, the separation film 6a will be described.

FIG. 2 shows another embodiment of the present invention, which is an essential part of an example of the constitution of an absorption chiller-heater in which the contact area between the absorption solution and the separation membrane is increased.

In the absorption chiller-heater 1a of another embodiment, as shown in FIG. 2, a hollow fiber-shaped separation membrane 6a having a predetermined length is bundled and disposed inside the regenerator 7, and a hollow fiber-shaped separation membrane 6a is formed. Separation membrane 6a
The absorption concentrated solution is brought into contact with one surface of the regenerator 7 from below to above, and the refrigerant vapor can be taken out from the other surface of the hollow fiber-shaped separation membrane 6a. The rest of the configuration is the same as that of the embodiment shown in FIG.

According to such another embodiment, the regenerator 7
However, the contact area between the concentrated absorption solution and the separation membrane 6a increases, and the amount of refrigerant vapor generated increases.

According to each of the above-mentioned embodiments, since the rectifier and the dephlegmator which are required to be provided in the conventional absorption chiller-heater main body are not required, the size of the entire apparatus can be reduced. In addition, according to each of the above-described embodiments, it is possible to separate a higher-purity refrigerant from the absorbing solution.

[0026]

As described above, according to the absorption chiller-heater of the present invention, since the refrigerant vapor can be separated from the concentrated absorption solution by the separation membrane, the equipment such as the rectifier and the dephlegmator are not required, and the entire apparatus can be obtained. There is an effect that can be miniaturized.

Further, according to the present invention, there is an effect that the separation membrane can separate a higher-purity refrigerant from the absorbing solution.

[Brief description of drawings]

FIG. 1 is a system diagram showing an embodiment of an absorption chiller-heater of the present invention.

FIG. 2 is a system diagram showing a main part of another embodiment of the present invention.

FIG. 3 is a system diagram showing a conventional absorption chiller-heater.

[Explanation of symbols]

 1 Absorption chiller / heater 1a Absorption chiller / heater 2 Absorber 3 Solution pump 4 Divider 5 Heat exchanger 6 Separation membrane 7 Regenerator 9 Cooling water 10 Condenser 11 Capillary 12 Evaporator

Claims (3)

[Claims] 1. A regenerator that heats a dilute solution containing a refrigerant by a heating source to produce a refrigerant vapor and an absorbing concentrated solution; an absorber that guides the concentrated solution from the regenerator to absorb the refrigerant vapor; Means for guiding a dilute solution that has absorbed refrigerant vapor in the absorber to the regenerator, a condenser that cools the refrigerant vapor generated in the regenerator into a condensed refrigerant, and guides the condensed refrigerant in the condenser, This condensed refrigerant is sprayed on an evaporator heat transfer tube to evaporate into a refrigerant vapor, and in an absorption chiller-heater equipped with an evaporator that supplies this refrigerant vapor to an absorber, in the regenerator, an absorption concentrated solution is formed. An absorption chiller-heater characterized by having a separation membrane that comes into contact with the concentrated concentrated solution to separate only the refrigerant vapor. 2. The absorption chiller-heater according to claim 1, wherein the separation membrane is arranged at a position in contact with the absorption solution in the regenerator. 3. The separation membrane, wherein the membrane is formed into a hollow fiber shape,
2. The absorption chiller-heater according to claim 1, wherein the absorbent solution is brought into contact with one surface of the hollow fiber and the refrigerant vapor is taken out from the other surface of the hollow fiber.