JP2000274734A - Fuel cell exhaust heat utilizing air-conditioning device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an air-conditioning device with high energy efficiency by combining a fuel cell, an absorption refrigerating machine, and a desiccant air conditioner for use. SOLUTION: In a desiccant air-conditioning device having a desiccant air conditioner that is provided with a desiccant member 12 which selectively contacts a processed air channel and a regenerated air channel, a heat exchanger for adjusting supply air temperature 20 that adjusts the temperature of the processed air in the processed air channel in the downstream side of the desiccant member, a heat exchanger for regenerating desiccant 13 that raises the temperature of the regenerated air in the regenerated air channel in the upstream side of the desiccant member, a fuel cell 40 that supplies a power source to a part of the desiccant air conditioner or an attached device thereof, and a heating medium channel 42 that circulates the heating medium for cooling of the fuel cell through the heat exchanger for regenerating desiccant are contained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an air conditioner,
Especially for desiccant regeneration and cooling / heating of treated air
The present invention relates to a fuel cell air conditioner using exhaust heat using a fuel cell and an absorption refrigerator.

[0002]

2. Description of the Related Art Conventionally, as a cooling and dehumidifying process of an air conditioner,
For example, a refrigerator that uses a refrigerator as a cooling source and performs a latent heat treatment on the treated air to dehumidify the air is used. In this case, when the amount of outside air taken into the room is large, or under conditions where the humidity in the room rises, such as when there is a device that evaporates moisture in the room, in order to keep the humidity in the room constant, A cycle of supercooling the air, dehumidifying and then reheating is required. Therefore, a low-temperature heat source lower than the originally required cooling temperature is required, and for this reason, it has been necessary to produce low-temperature cold water of, for example, about 7 ° C. with an absorption refrigerator.

[0003] This will be described with reference to a psychrometric chart shown in FIG. 8. Return air from the room to be air-conditioned (state G) is mixed with outside air (state A) (state B), and absorption refrigeration is performed. To reach the saturated vapor pressure of the treated air (state C). Then, after being cooled along the saturation curve and dehumidified (state D), it is heated and supplied into the room (state E). Here, in the supercooled state D, the temperature of the chilled water supplied from the absorption refrigerator is about 7 ° C., whereby the temperature in the state D becomes about 13 ° C.

[0004] In order to prevent such excessive cooling, an air conditioner as shown in FIG. 9 has been proposed. Here, reference numeral 10 denotes an air conditioning space, 11 denotes a blower, 12 denotes a desiccant member (desiccant rotor) containing a desiccant that can selectively contact processing air and regeneration air, and 13 denotes a heat exchanger for adjusting supply air temperature. , 14
Is a humidifier, 15 to 19 are processing air paths, 20 is a heat exchanger for desiccant rotor regeneration, 21 is a regeneration air blower, 22 to 25 is regeneration air path, and 26 is processing from outside air of regeneration air. These are air paths to the air circulation, and these constitute the desiccant air conditioner 1. Reference numeral 27
Is a cold heat source, 28 is a pump, 29 is a warm heat source, 30 is a pump, and 31 to 34 are heat medium paths. In addition, SA indicates supply air, RA indicates return air, OA indicates outside air, and EX indicates exhaust.

[0005] Here, "desiccant" means a desiccant, and its type includes activated carbon and activated alumina. The “desiccant member” is a member filled with such a desiccant, and in this case, is a “desiccant rotor” configured to be rotatable in a disk or column shape. The desiccant rotor is disposed across the processing air path 16 and the regeneration air path 23 as shown in FIG. 9 and continuously rotates at a low speed of, for example, several revolutions per hour. Dehumidification of the processing air and regeneration with the regeneration air are performed.

In such a configuration, the return air (condition G) RA from the room 10 to be air-conditioned is mixed with the outside air (state A) OA from the path 26 in the middle of the path 15 (state B), and The desiccant rotor 12 sucks the water and sends it to the desiccant rotor 12 via the path 16, and the desiccant of the desiccant rotor 12 adsorbs moisture. Thereby, the absolute humidity decreases and the temperature rises due to heat of adsorption (state F). The air whose humidity has decreased and whose temperature has increased is sent to the heat exchanger 13 via the path 17 and exchanged with the refrigerant from the cold heat source 27 to be cooled (state E). The cooled air is returned to the air-conditioned space 10 via the path 18 and the supply air SA via the path 19.

[0007] The regeneration of the desiccant adsorbing water in the above process is performed as follows using the outside air. That is, the outside air (OA) is sucked into the blower 21 and sent to the heat exchanger 20 via the path 22, exchanges heat with the heat medium from the heat source 28, is heated, and rises in temperature to 60 to 65 ° C. Humidity decreases. The regenerated air having a reduced relative humidity passes through the desiccant rotor 12 to remove the desiccant water. The regenerated air that has passed through the desiccant rotor 12 flows into the blower 21 through the path 24, and is discarded outside through the path 25 as exhaust EX.

FIG. 10 shows a modification of the air conditioner shown in FIG. In this example, the desiccant air conditioner 1 includes a desiccant regeneration unit 1A including a desiccant rotor 12 and a heat exchanger 20 for regenerating the desiccant rotor 12, and a heat exchanger 13 and a humidifier 14 for adjusting supply air temperature. The air temperature adjusting unit 1B is divided and configured.

[0009]

However, in such an air conditioner, the desiccant rotor 1 is not operated during the cooling operation.
Heat source 29 for regenerating 2 and desiccant rotor 1
It is necessary to operate the cooling air source 27 for cooling the processing air that has passed through 2 at the same time. Therefore, conventionally, it has been necessary to separately install a hot water boiler as the heat source 29 or to operate a heat source for heating. However, such a conventional device has a problem that the initial cost increases in the former case and the running cost increases in the latter case. As a result, there is a problem that a sufficient energy saving effect cannot be obtained. .

[0010] The present invention has been made in view of the above, and an object of the present invention is to provide an air conditioner having high energy efficiency by using a combination of a fuel cell, an absorption refrigerator and a desiccant air conditioner.

[0011]

According to a first aspect of the present invention, there is provided an air conditioner having a desiccant air conditioner having a desiccant member selectively contacting a processing air flow path and a regeneration air flow path, wherein the processing air is supplied to the processing air flow path. A supply air temperature adjustment heat exchanger for adjusting the temperature in the processing air flow path downstream of the desiccant member; and a desiccant regeneration heat exchanger for raising the temperature of the regeneration air in the regeneration air flow path upstream of the desiccant member. And a fuel cell for supplying power to a part of the desiccant air conditioner or an auxiliary device thereof, and a heat medium flow path for flowing a heat medium for cooling the fuel cell to the heat exchanger for desiccant regeneration. A fuel cell air conditioner utilizing exhaust heat.

[0012] In the air conditioner thus constructed, the exhaust heat of the fuel cell is supplied to the desiccant regeneration heat exchanger of the desiccant air conditioner and used as a heat source for desiccant regeneration, so that an air conditioning system with high energy savings is provided. It is possible to construct In addition, there is no need to separately install a regenerative heat source, so that equipment costs can be reduced. Furthermore, since the latent heat of the processing air is processed using a desiccant, the heat exchanger for adjusting the supply air temperature only needs to perform sensible heat treatment, and is supplied from the refrigerator or the like to the heat exchanger for adjusting the supply air temperature during cooling. The refrigerant temperature is improved at a higher temperature than before. Therefore, for example, when an absorption refrigerator is used, its coefficient of performance (COP) is improved, and higher energy saving efficiency is obtained. The heat medium for cooling the fuel cell may be selectively circulated to one of the heat exchanger for adjusting the supply air temperature and the heat exchanger for desiccant regeneration.

According to a second aspect of the present invention, a plurality of the desiccant air conditioners are provided for one fuel cell, and the air conditioner utilizing exhaust heat of the fuel cell according to the first aspect of the present invention is provided. Device. Thereby, for example, the fuel cell and the absorption refrigerator are configured as a central unit, and the exhaust heat and absorption of the fuel cell are respectively supplied to the desiccant regeneration heat exchanger or the supply air temperature adjustment heat exchanger of the plurality of desiccant air conditioners. By supplying the refrigerant of the type refrigerator, it is possible to construct an air conditioning system suitable for a large building having a plurality of air conditioning spaces.

According to a third aspect of the present invention, there is provided the desiccant system according to the first or second aspect, wherein the fuel cell is a polymer electrolyte fuel cell. In a polymer electrolyte fuel cell, the cooling water temperature is about 74
° C, and when this cooling water exchanges heat with regeneration air in a desiccant regeneration heat exchanger, the regeneration air is heated to about 6 ° C.
0-65 ° C, which is fed to the desiccant. Therefore, there is an advantage that the cooling water can be supplied to the desiccant regeneration heat exchanger at the same temperature, and the system can be simplified. On the other hand, in other types of fuel cells such as a phosphoric acid type, since the cooling water becomes steam, a facility for treating condensed water after heat exchange is required, and the system becomes complicated.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a fuel cell exhaust heat utilizing air conditioner according to the present invention will be described with reference to the drawings.
In each drawing, the same components as those in FIG. 9 are denoted by the same reference numerals, and description thereof will be simplified. FIG. 1 shows the overall configuration of an air conditioner. The desiccant air conditioner 1 is configured as follows, as in the conventional example shown in FIG. That is, the air-conditioned space 10 is connected to the suction port of the blower 11 for processing air via the path 15,
One discharge port is connected to the desiccant rotor 12 via a path 16. The outlet of the processing air of the desiccant rotor 12 is further connected to a heat exchanger for adjusting the supply air temperature (heat exchanger for adjusting the supply air temperature) 13 via a path 17, and
The outlet of the processing air of No. 3 is connected to the humidifier 14 via the path 18, and the outlet of the processing air of the humidifier 14 is connected to the air-conditioned space 10 via the path 19. Thus, a processing air path for processing the processing air is formed.

On the other hand, in the regeneration air path through which the regeneration air flows, outside air OA passes through a desiccant rotor regeneration heat exchanger (desiccant rotor regeneration heat exchanger) 20 and path 2.
2 and at the middle of the processing air path 15 via a path 26. Heat exchanger 20
The outlet of the regeneration air is connected to the regeneration air inlet of the desiccant rotor 12 through a path 23, and the desiccant rotor 1
The outlet of the regeneration air of No. 2 is connected to a suction port of a blower 21 for regeneration air via a path 24, and an outlet of the blower 21 is connected to an external space via a path 25. As a result, a regeneration air path is configured in which the regeneration air is taken in from the outside and heated, the desiccant is dehumidified and then exhausted to the outside.

In the embodiment shown in FIG. 1, a polymer electrolyte fuel cell 40 having a structure as shown in FIG. 2 is provided as a part of a driving energy source of an air conditioner. Combined composite energy sources are used. That is, the regeneration heat exchanger 20 is connected to the drainage path of the fuel cell 40 by the circulation path having the pump 44, the cooling water supply path 42, and the return path 43. Further, the heat exchanger 13 for adjusting the supply air temperature is connected to the absorption refrigerator 41 by a circulation flow path having a pump 49, a supply path 47 for cold water, and a return path 48.

The fuel cell 40 includes a hydrogen production apparatus 40A for producing hydrogen from fuel F such as city gas, and a cell body 4 for generating electricity by a chemical reaction between the hydrogen and oxygen in the air.
0B. The heat generated by this chemical reaction is carried away by the cooling water flowing through the cooling water supply path 42 and the return path 43, and heats the regeneration air flowing through the regeneration air path in the heat exchanger 20.

This apparatus is provided with a cooling tower 52, which is provided with a circulation path having a pump 55, a cooling water supply path 53 and a return path 54 by an absorption type refrigerator 4.
1 connected. Note that the fuel cell 40 is also connected to the absorption refrigerator 41 by a cooling water supply path 45 and a return path 46. The cooling water supply path 42 of the fuel cell 40 and the cooling water supply path 47 of the absorption refrigerator 41, and the return path 43 and the return path 48 are connected to each other by a supply path 50 and a return path 51, respectively. I have.

Next, the operation of the air conditioner utilizing the exhaust heat from the fuel cell will be described. First, the operation during the cooling operation will be described. As shown in FIG. 3, return air (process air) RA from the room 10 to be air-conditioned
Is mixed with the outside air (regenerated air) OA from the path 26, the air is sucked by the blower 11 and pressurized, sent to the desiccant rotor 12 via the path 16, and desiccant of the desiccant rotor 12 Is absorbed to lower the absolute humidity. At the time of adsorption, the temperature of air rises due to heat of adsorption. The air whose humidity has dropped and the temperature has risen is sent to the heat exchanger 13 via the path 17 and
It is cooled by exchanging heat with the cold water from Step 1. The cooled air is returned to the air-conditioned space 10 through paths 18 and 19 as air supply SA.

The desiccant adsorbing moisture in the above process is
It is reproduced as follows using the outside air. That is, the outside air (OA) is sucked into the blower 21 and sent to the heat exchanger 20 via the path 22, exchanges heat with the cooling water from the fuel cell 40 and is heated to a temperature of about 60 to 65 ° C. Relative humidity decreases. The regenerated air having a reduced relative humidity passes through the desiccant rotor 12 to remove the desiccant water. The regenerated air that has passed through the desiccant rotor 12 passes through path 2
4 flows into the blower 21 and is discarded outside through the path 25 as exhaust EX.

The fuel cell 40 produces hydrogen from a fuel F such as city gas in a hydrogen producing apparatus 40A,
At 0B, power is generated by a chemical reaction between hydrogen and oxygen in the air. This electric power is used as a power supply for operating the absorption heat pump and its associated devices and a power supply for other facilities.

The cooling water flowing out of the fuel cell 40 is supplied to the heat exchanger 20 for desiccant regeneration by the pump 44 through the supply path 42, and exchanges heat with the regeneration air.
It is returned through the return path 43. In this embodiment,
Since the fuel cell 40 is of a solid polymer type, the temperature in the cooling water supply path 42 is about 74 ° C., and the cooling water exchanges heat with the regeneration air in the heat exchanger 20, and the return path 43 The temperature will be about 71 ° C. On the other hand, the regenerated air is heated by the heat exchanger 20, and the temperature in the path 23 becomes about 60 to 65 ° C., which is supplied to the desiccant rotor 12.

A part of the cooling water of the fuel cell 40 is circulated and supplied to the absorption refrigerator 41 through a supply path 45 and a return path 46 as a heat source of the absorption refrigerator 41, 55 allows the cooling water to flow through the supply path 53 and the return path
1, and chilled water is generated. This cold water
The heat is supplied to the heat exchanger 13 for adjusting the supply air temperature through the supply path 47 by the pump 49 and exchanged with the processing air, and then returned through the return path 48.

The process up to now will be described with reference to the psychrometric chart of FIG. 8. Return air RA from the room 10 to be air-conditioned (state G) is generated from outside air from the path 26 in the course of the path 15 (state A). ) Is mixed with OA (state B), further sucked by the blower 11, sent to the desiccant rotor 12 via the path 16, and adsorbed by the desiccant of the desiccant rotor 12. Thereby, the absolute humidity decreases and the temperature rises due to heat of adsorption (state F). Humidity drops,
The air whose temperature has risen is sent to the heat exchanger 13 via the path 17 and is cooled by exchanging heat with the refrigerant from the cold heat source 47 (state E). The cooled air is returned to the air-conditioned space 10 through paths 18 and 19 as air supply SA. Here, state E
In, for example, the temperature of the cold water supplied from the absorption refrigerator 41 is about 10 ° C., whereby the temperature in the state G becomes about 16 ° C.

Next, the operation during the heating operation will be described with reference to FIG. The fuel cell 40 generates power, and its cooling water is supplied by a pump 44 to supply paths 42, 50, 47.
The air is supplied to the heat exchanger 13 for adjusting the supply air temperature through the air passage and exchanges heat with the air. Thereby, the air (heating air) that has exchanged heat in the heat exchanger 13 is heated. Heated air is in path 1
8, is sent to the humidifier 14, is humidified by water injection or vaporization humidification, and is returned to the conditioned space as the supply air SA via the path 19. During the heating operation, the desiccant rotor 12 is stopped, so that the desiccant regeneration process is stopped.

In the air conditioner utilizing the exhaust heat of the fuel cell, the cooling water (exhaust heat) of the fuel cell 40 is used as a heat source for regenerating the desiccant of the desiccant rotor 12.
Therefore, an air conditioner with good energy saving can be constructed. Further, since there is no need to separately install a regeneration heat source, it is possible to reduce equipment costs.
Further, the desiccant rotor 12 performs a dehumidification (latent heat) process in advance, so that the heat exchanger 13 for adjusting the supply air temperature only needs to perform the sensible heat treatment, and is supplied to the heat exchanger 13 for adjusting the supply air temperature during cooling. The temperature of the chilled water to be cooled can be increased to a higher temperature, for example, from about 7 ° C. to about 10 ° C. Therefore, the absorption refrigerator 41 driven by using the cooling water of the fuel cell 40 can be downsized, and the cost can be reduced. Further, C of the absorption refrigerator 41
OP is improved, and higher energy saving efficiency can be achieved. As described above, the energy efficiency of the entire system can be improved.

FIG. 5 is a view showing another embodiment of the air conditioner utilizing the exhaust heat of a fuel cell according to the present invention. In this embodiment, the fuel cell 40 and the absorption refrigerator 41
Is arranged in one place as a central unit 2, while a plurality (three in FIG. 5) of desiccant air conditioners 1 are arranged so that a plurality of air-conditioned spaces can be air-conditioned.

The desiccant regeneration heat exchangers 20 of the desiccant air conditioners 1 have supply paths 42a, 42b, 42c and return paths branched from the supply path 42 and return path 43 of the cooling water of the fuel cell 40, respectively. 43a, 4
3b and 43c are connected. In addition, the heat exchangers 13 for adjusting the supply air temperature of the desiccant air conditioners 1 are provided with supply paths 47a, 47b, and 47c branched from the supply path 47 and the return path 48 of the chilled water of the absorption refrigerator 41, respectively.
And return paths 48a, 48b, 48c are connected.

In such an air conditioner utilizing waste heat from a fuel cell, as shown in FIG.
Generates electric power, supplies the cooling water to each desiccant regeneration heat exchanger 20 of each desiccant air conditioner 1, and supplies the cold water of the absorption refrigerator 41 to each supply air temperature adjustment heat exchanger. 13 is supplied. Other operations are shown in FIG.
This is similar to the above-described embodiment. During the heating operation, as shown in FIG. 7, the cooling water of the fuel cell 40 is supplied to the heat exchanger 13 for adjusting the supply air temperature of each desiccant air conditioner 1. Other operations are the same as those of the above-described embodiment shown in FIG.

In each of the above embodiments, the desiccant air conditioner 1 is a single unit. However, the desiccant air conditioner 1 is connected to the desiccant rotor 12 and the And a desiccant regeneration unit 1A including a heat exchanger 20 and a supply air temperature adjustment unit 1B including a heat exchanger 13 and a humidifier 14 for adjusting the supply air temperature. Needless to say.

[0032]

As described above, according to the present invention,
Combining a fuel cell, an absorption refrigerator and a desiccant air conditioner, the exhaust heat of the fuel cell is used as a heat source for desiccant regeneration, and the desiccant is preliminarily dehumidified (latent heat) treated to adjust the air supply temperature during cooling. By making it possible to increase the temperature of the refrigerant supplied to the heat exchanger for use, it is possible to increase the energy efficiency. In particular, the present invention is a facility with a high power demand and a high outside air intake, such as a supermarket, a convenience store or a pachinko store, or a facility with a high power demand and requiring dehumidifying air conditioning, such as a hospital or It is suitable if applied to a clean room or the like.

[Brief description of the drawings]

FIG. 1 is a diagram for explaining a basic configuration of an embodiment of a fuel cell exhaust heat utilizing air conditioner according to the present invention.

FIG. 2 is a diagram for explaining the relationship between the fuel cell according to the present invention and the heat exchanger for desiccant regeneration, and is a partially simplified schematic diagram.

FIG. 3 is a diagram for explaining an operation during a cooling operation of the air conditioner using exhaust heat from fuel cells shown in FIG. 1;

FIG. 4 is a diagram for explaining an operation during a heating operation of the fuel cell exhaust heat utilizing air conditioner shown in FIG. 1;

FIG. 5 is a diagram for explaining a basic configuration of another embodiment of the fuel cell air conditioner utilizing waste heat of the present invention.

6 is a diagram for explaining an operation of the fuel cell exhaust heat utilizing air conditioner shown in FIG. 5 during a cooling operation.

FIG. 7 is a diagram for explaining an operation during a heating operation of the air conditioner using exhaust heat from fuel cells shown in FIG. 5;

FIG. 8 is a psychrometric chart for explaining the operation of the air conditioner.

FIG. 9 is a diagram for explaining a conventional air conditioner.

FIG. 10 is a diagram for explaining a modification of FIG. 9;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Desiccant air conditioner 1A Desiccant regeneration unit 1B Supply air temperature adjustment unit 2 Central unit 10 Air conditioning space 12 Desiccant rotor 13 Heat exchanger for supply air temperature adjustment (heat exchanger for supply air temperature adjustment) 20 Heat exchange for desiccant regeneration (Heat exchanger for desiccant regeneration) 40 Fuel cell 41 Absorption refrigerator SA Supply air RA Return air OA Outside air EX Exhaust

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kaki Yoshida 11-1 Haneda Asahimachi, Ota-ku, Tokyo F-term in Ebara Corporation 3L053 BC03

Claims (3)

[Claims] 1. An air conditioner having a desiccant air conditioner having a desiccant member selectively contacting a processing air flow path and a regeneration air flow path, wherein processing air is heated in the processing air flow path downstream of the desiccant member. A heat exchanger for adjusting the supply air temperature to be adjusted; a heat exchanger for desiccant regeneration for raising the temperature of the regeneration air in the regeneration air flow path on the upstream side of the desiccant member; and a part of or an attachment to the desiccant air conditioner An air conditioner utilizing exhaust heat from a fuel cell, comprising: a fuel cell for supplying power to the device; and a heat medium passage for flowing a heat medium for cooling the fuel cell to the heat exchanger for desiccant regeneration. 2. The air conditioner according to claim 1, wherein a plurality of the desiccant air conditioners are provided for one fuel cell. 3. The air conditioner according to claim 1, wherein the fuel cell is a polymer electrolyte fuel cell.