DE112018000106T5 - FUEL CELL SYSTEM - Google Patents

Abstract

In order to provide a fuel cell system that can cool exhaust gas from a fuel cell with an efficient and simple configuration, a fuel cell (20) is disposed in a main aggregate chamber (11), and a radiator (40) for introducing a cooling air is disposed in the accessory chamber (12 ) arranged. A ceiling perforation section (13) is disposed in the accessory chamber (12) to externally remove the cooling air introduced into the accessory chamber (12) through the radiator (40). An exhaust gas guide pipe (30) guides the exhaust gas from the fuel cell (20) from the main aggregate chamber (11) via the accessory chamber (12) to the ceiling perforation section (13) and projects upwardly above the ceiling perforation section (13). A first baffle plate (62) is disposed to surround the exhaust guide tube (30) above the ceiling perforation section (13). A second baffle plate (63) is arranged to face a tip of the exhaust gas guide tube (30) above the ceiling perforation section (13).

Description

FIELD OF THE INVENTION

The present invention relates to a fuel cell system.

BACKGROUND OF THE INVENTION

Patent Document 1 discusses a fuel cell system that can enable efficient operation of a fuel cell by arranging internal units such that a difference between an air inlet temperature and an air outlet temperature of the fuel cell is reduced. As a configuration for this purpose, a plurality of cooling fans are arranged in a region covering all surfaces including the front, rear and side surfaces of the fuel cell (for example, nine cooling fans arranged along three vertical rows and three horizontal rows are both provided on the front and on the rear side), so that ventilation from the outside air side to the fuel cell can be performed. In addition, a fan is arranged in the bottom of the fuel cell, so that the waste heat of the fuel cell is collected by means of the fan and discharged to the underlying waste heat passage. In addition, a fan (a second fan) for cooling a control device is provided by sucking the air from the waste heat passage side and blowing it to the control device. It is possible to control a ventilation amount introduced into the waste heat passage, ventilation amounts to an air pump, an air supply pipe and a humidifier, or a temperature by controlling flow rates of the two fans using the control device.

In the prior art fuel cell system, a technical problem is how to make waste heat treatment of the hot exhaust gases from the fuel cell (for example, a fuel gas and an oxidant gas that do not react electrochemically, a combustion gas obtained by burning the fuel gas, and the oxidant gas or the like).

[Citation List]

[Patent Documents]

Patent Document 1: Japanese Unexamined Patent Application Publication No. 2015-72879

BRIEF SUMMARY OF THE INVENTION

For example, as one of the solutions to the above-mentioned technical problems, it would be conceivable to use a configuration in which the heat of the exhaust gas is recovered by using warm water and the heat is discharged by using a waste heat recovery heat exchanger (hot water heat exchanger). In addition, in a case where the waste heat is not used (when the exhaust heat recovery heat exchanger is not operated), it would be conceivable to perform cooling using a radiator or a dilution using a dilution air blower to exhaust the exhaust gas by lowering the exhaust gas temperature.

However, in the prior art fuel cell system, such as in the case of the technique of Patent Document 1, the number of devices due to the exhaust gas refrigerant from the fuel cell (for example, a radiator or a dilution air blower when waste heat is not used) increases. This can increase the size or the cost of the device and degrade the power generation efficiency due to the higher line consumption of the accessories. In particular, in a case where a large commercial solid oxide fuel cell (SOFC) is used as the fuel cell, the exhaust gas from the SOFC has a very high temperature, so that the above-mentioned technical problems become more pronounced.

In view of the above-mentioned problems, therefore, an object of the invention is to provide a fuel cell system capable of implementing cooling of the exhaust gas from the fuel cell with an efficient and simple configuration.

According to one aspect of the present invention, there is provided a fuel cell system including: a main aggregate chamber in which a fuel cell is disposed; an accessory chamber in which a radiator for introducing a cooling air is arranged; a ceiling perforation section disposed in the accessory chamber for externally discharging the cooling air introduced into the accessory chamber through the radiator; an exhaust guide pipe protruding upward from the ceiling perforation section to guide an exhaust gas from the fuel cell from the main aggregate chamber via the accessory chamber to the ceiling perforation section; a first baffle arranged to surround the exhaust duct above the ceiling perforation section; and a second baffle arranged so as to be a tip of the Exhaust duct facing the Deckenperforationsabschnitt.

According to the present invention, it is possible to provide a fuel cell system that can implement cooling of the exhaust gas from the fuel cell with an efficient and simple configuration.

list of figures

• 1 FIG. 12 is a block diagram illustrating a fuel cell system according to a first embodiment; FIG.
• 2 FIG. 12 is an interior perspective view illustrating an internal configuration of a ceiling chamber; FIG.
• 3 Fig. 12 is a conceptual diagram for describing an air flow inside the ceiling chamber; and
• 4 FIG. 11 is a conceptual diagram illustrating a fuel cell system according to a second embodiment as compared with FIG 3 illustrated.

DESCRIPTION OF EMBODIMENTS

«First embodiment»

A fuel cell system 1 According to a first embodiment is with reference to the 1 to 3 described. Each of upper, lower, front, rear, left and right directions in the 2 and 3 based on arrow directions, which are indicated in the drawings. In 1 a thin solid line indicates a flow of a fluid such as gas or water, and a thin dash line indicates a flow of electricity or signals. Also indicated in 1 a thick solid line forms part of an outer profile (contour) of the housing unit 10 and a thick dash line indicates a boundary between a main aggregate chamber 11 and an accessory chamber 12 ,

The fuel cell system 1 has a box-shaped housing unit 10 , The interior of the housing unit 10 is in the main aggregate chamber 11 and the accessory chamber 12 divided. The main aggregate chamber 11 and the accessory chamber 12 may be partitioned by a bulkhead (not shown) to guarantee an explosion-proof structure. Alternatively, the main aggregate chamber 11 and the accessory chamber 12 in a single chamber in fluid communication with each other without being partitioned by the partition, as long as an explosion-proof structure is guaranteed therebetween.

As a fuel cell, a solid oxide fuel cell (SOFC) 20 inside the main aggregate chamber 11 arranged. Although not shown in the drawings, the SOFC has 20 a cell stack formed by stacking multiple cells or configured as a module. Each cell has a basic configuration in which electrolyte is disposed between an air electrode and a fuel electrode and a separator is interposed between each cell. Each cell of the cell stack is electrically connected in series. The SOFC 20 has an electricity generation mechanism in which oxide ions generated in the air electrode move through the electrolyte to the fuel electrode and the oxide ions in the fuel electrode react with hydrogen or carbon monoxide to generate electrical energy.

Although not shown in the drawings, the SOFC has 20 a fuel gas flow path for supplying the fuel gas from a fuel gas supply unit and an oxidant gas flow path for supplying the oxidizing gas from an oxidizing gas supply unit. The fuel gas supplied to the fuel gas flow path and the oxidizing gas supplied to the oxidant gas flow path electrochemically react with each other to generate a direct current. The fuel gas and the oxidizing gas, which do not contribute to the electrochemical reaction, are referred to as an exhaust gas of the SOFC 20 drained. It should be noted that a combustor (not shown) for removing a fuel component remaining in the exhaust gas by burning the exhaust gas from the SOFC 20 inside the main aggregate chamber 11 can be present. The exhaust gas from the SOFC 20 has a high temperature of, for example, 300 ° C or more.

The exhaust gas from the SOFC 20 is from the main aggregate chamber 11 via the accessory chamber 12 through an exhaust pipe 30 into the vicinity of a below-described ceiling perforation section (accessory chamber outlet port) (see 2 and 3 ). A concrete pipe structure of the exhaust pipe 30 is described below.

Various accessory components (not shown), such as an electromagnetic valve or flowmeter, are located inside the accessory chamber 12 arranged. There is also a cooling fan (such as an accessory chamber fan, radiator, or cooler) 40 for introducing the cooling air from outside the accessory chamber 12 and to cool the accessory components during operation inside the accessory chamber 12 arranged. In addition, the ceiling perforation section (accessory chamber outlet port) is 13 which has several perforations, the For example, be formed by punching metal or the like, on the ceiling surface of the accessory chamber 12 arranged. The through the cooling fan 40 introduced cooling air spreads to the inside of the accessory chamber 12 and to cool the accessory components during operation, and then goes up through the ceiling perforation section 13 discharged. Because of the cooling fan 40 introduced cooling air the exhaust pipe 30 In addition, it has the function of cooling the exhaust gas from the SOFC 20 passing through the interior of the exhaust pipe 30 is directed.

A waste heat recovery heat exchanger (hot water heat exchanger) 50 is inside the accessory chamber 12 arranged. The waste heat recovery heat exchanger 50 Wins the heat of the exhaust gas from the SOFC 20 back. A waste heat recovery circulation pipe 51 by which water (hot water) is circulated as a heat medium for recovering the waste heat is with the waste heat recovery heat exchanger 50 coupled. The waste heat recovery circulation pipe 51 has a downstream pipe 51A by the relatively high temperature water (hot water) from the waste heat recovery heat exchanger 50 flows, and an upstream pipe 51B , through the water at a relatively low temperature (hot water) in the direction of the waste heat recovery heat exchanger 50 flows. Whether the waste heat recovery using the waste heat recovery heat exchanger 50 is executed or not (whether a cogeneration operation or a mono-generation operation is performed) is controlled by a control unit (not shown).

A ceiling chamber 60 is above the ceiling perforation section 13 the accessory chamber 12 arranged. Although 1 a configuration of the ceiling chamber 60 illustrated in a simplified manner, become an interior configuration of the ceiling chamber 60 and an air flow inside the ceiling chamber 60 in detail with reference to the 2 and 3 described.

The ceiling chamber 60 has a rectangular or cubic box shape. The ceiling chamber 60 acts as a vent channel for mixing the exhaust gas from the SOFC 20 passing through the exhaust pipe 30 is guided, and by the cooling fan 40 introduced cooling air to produce a gas mixture and remove the gas mixture to the outside. Besides, the ceiling chamber has 60 the function of preventing foreign objects, such as rainwater or birds, through the ceiling perforation section 13 in the accessory chamber 12 reach. It should be noted that a rainwater drainage hole or a rainwater drainage channel is preferable in a lower part of the ceiling chamber 60 is arranged.

Several perforations formed by, for example, punching out metal or the like are on top of the ceiling chamber 60 arranged as a withdrawal port (last withdrawal port) 61. The underside of the ceiling chamber 60 is configured to be larger than the ceiling perforation section 13 the accessory chamber 12 and - seen in a plan view - the Deckenperforationsabschnitt 13 covered.

As described above, the ceiling perforation section has 13 the accessory chamber 12 a plurality of perforations formed by punching metal or the like, for example, and an opening 14 will be in the middle of the ceiling perforation section 13 educated. The exhaust pipe 30 that is different from the SOFC 20 the main aggregate chamber 11 via the waste heat recovery heat exchanger 50 the accessory chamber 12 extends, projects upwards through the opening 14 , That is, a tip of the exhaust pipe 30 is in the ceiling chamber 60 used.

Inside the ceiling chamber 60 is a first baffle or baffle 62 arranged, which - seen in a plan view - has substantially an H-shape and a plan view of the ceiling chamber 60 equivalent. The first baffle or guide plate 62 has a pair of left and right opposite sides 62A extending in front-to-back direction and a connection side 62B extending in a direction from left to right, around middle portions of the front-rear direction of the pair of opposite sides 62A connect to. cavities 62C , which generally serve as a flow passage of the cooling air, are both in the front and in the back of the connection side 62B educated. An opening 62D is in the middle of the first baffle or baffle 62 designed so that the exhaust pipe 30 up through the opening 62D protrudes. In this way, the first baffle or baffle is 62 arranged so that they are the exhaust pipe 30 above the ceiling perforation section 13 surrounds. It should be noted that the first baffle or baffle plate 62 the function has, the exhaust pipe 30 inside the ceiling chamber 60 to position and fix.

Inside the ceiling chamber 60 is a second baffle or baffle 63 which has a substantially H-shape as seen in a plan view and a plan view shape of the ceiling chamber 60 corresponds, above the first baffle or baffle 62 arranged. The second baffle or guide plate 63 has a pair of front and back facing sides 63A that are in the left-right direction extend, and a connection side 63B extending in the front-rear direction, around middle portions of the left-right direction of the pair of opposing sides 63A connect to. cavities 63C , which generally serve as a flow passage of the gas mixture of the exhaust gas and the cooling air, are in both the left and in the right side of the connection side 63B educated. The second baffle or guide plate 63 is arranged so that it is the tip of the exhaust pipe 30 above the ceiling perforation section 13 is facing.

The first baffle or guide plate 62 and the second baffle or baffle 63 which are both substantially H-shaped in a plan view are arranged to deviate from each other by a relative phase difference of 90 °. Because of this, stand the cavity 62C the first baffle or baffle 62 and the cavity 63C the second baffle or baffle 63 not in vertical communication with each other, and the two cavities 62C and the two cavities 63C are each in four sides of the ceiling chamber 60 - Seen in a plan view - positioned.

In the fuel cell system 1 , which is configured as described above, spreads through the cooling fan 40 introduced cooling air so that they are the interior of the accessory chamber 12 and cools the accessory components (not shown) during operation and then into the interior of the ceiling chamber 60 above the ceiling perforation section 13 entry. Furthermore, the exhaust gas from the SOFC 20 through the exhaust pipe 30 to the ceiling perforation section 13 guided and is between the first baffle or baffle plate 62 and the second baffle or baffle 63 inside the ceiling chamber 60 drained. Because of the cooling fan 40 introduced cooling air the exhaust pipe 30 inside the accessory chamber 12 surrounds, at this moment the exhaust gas from the SOFC 20 passing through the interior of the exhaust pipe 30 is led, cooled. Because the exhaust gas from the SOFC 20 passing through the exhaust pipe 30 is guided, and through the cooling fan 40 introduced cooling air inside the accessory chamber 12 In addition, it is possible to increase the pressure loss inside the accessory chamber 12 to prevent.

Most of the cooling air passing through the ceiling perforation section 13 into the interior of the ceiling chamber 60 enters, meets the bottom of the first baffle or baffle 62 and then goes up through the cavity 62C and a small part of it goes through the cavity 62C without hitting the bottom of the first baffle or baffle 62 hold true. In addition, between the first baffle or baffle 62 and the second baffle or baffle 63 the cooling air passing through the cavity 62C rises, and the exhaust gas from the SOFC 20 that of the exhaust pipe 30 was discharged, vortexed and mixed (diluted) to produce a gas mixture. Because the first baffle or baffle 62 and the second baffle or baffle 63 by a phase difference of 90 ° from each other (the cavities 62C and 63C here are not in fluid communication with each other in the vertical direction), it is possible here to obtain an excellent cooling efficiency (dilution efficiency), by the residence times of the cooling air and the exhaust gas between the first baffle or baffle 62 and the second baffle or baffle 63 be extended.

The exhaust gas from the SOFC 20 coming from the exhaust pipe 30 is discharged, for example, in an operating state of the waste heat recovery heat exchanger 50 (during the cogeneration operation) has a temperature of about 90 ° C and has in a non-operating state of the waste heat recovery heat exchanger 50 (during the mono-generation operation) a temperature of about 360 ° C. In comparison, the cooling air that comes from the accessory chamber 12 through the ceiling perforation section 13 into the interior of the ceiling chamber 60 occurs, for example, a temperature of about 60 ° C. Here, since a flow rate of the cooling air is much larger than a flow rate of the exhaust gas, it is possible to maintain the temperature of the gas mixture obtained by swirling and mixing (diluting) the cooling air and the exhaust gas even in a non-operating state of the exhaust heat recovery heat exchanger 50 to lower to less than 260 ° C (for example, up to a maximum of about 80 ° C).

The turbulent and mixed (dilute) gas mixture between the first baffle or baffle 62 and the second baffle or baffle 63 rises through the cavity 63C the second baffle or baffle 63 and is from a deduction port 61 drained to the outside.

Near the ceiling perforation section 13 the accessory chamber 12 (For example, inside the ceiling chamber 60 ) is a temperature detector 70 for detecting an air temperature (for example, a temperature of the gas mixture inside the ceiling chamber 60 swirled and mixed (diluted) is placed). There is also a control unit 80 for controlling the cooling fan 40 on the basis of a detection result of the temperature detector 70 inside the accessory chamber 12 arranged. As a control type of the control unit 80 For example, a Variable Voltage Variable Frequency (VVVF) control can be used. The control unit 80 controls an on / off state of the cooling fan 40 , an exhaust gas flow rate or the like so that the detection temperature of the temperature detector 70 is not greater than a predetermined temperature threshold (for example 260 ° C).

Alternatively, the temperature detector 70 inside the accessory chamber 12 be arranged so that the control unit 80 the cooling fan 40 on the basis of a detection result of the temperature detector 70 can control. In this case, the control unit controls 80 an on / off state of the cooling fan 40 , an exhaust gas flow rate or the like so that the temperature of the gas mixture flowing from the exhaust port 61 the ceiling chamber 60 is not greater than a predetermined temperature threshold (for example, 260 ° C).

This way is in the fuel cell system 1 According to the first embodiment, the SOFC (fuel cell) 20 in the main aggregate chamber 11 arranged, and the cooling fan (radiator) 40 for introducing the cooling air is in the accessory chamber 12 arranged so that through the cooling fan 40 in the accessory chamber 12 introduced cooling air through the ceiling perforation section (accessory chamber outlet port) 13 is drained to the outside, and the exhaust gas from the SOFC 20 is from the main aggregate chamber 11 via the accessory chamber 12 through the exhaust pipe 30 to the ceiling perforation section 13 guided. As a result, the exhaust gas from the SOFC 20 by the cooling air near the ceiling perforation section 13 cooled (diluted) (the exhaust gas from the SOFC 20 is using the through the cooling fan 40 introduced cooling air cooled (diluted)). Therefore, it is possible to cool the exhaust gas from the SOFC 20 with an efficient and simple configuration to implement. That is, since it is not necessary, a coolant for the exhaust gas from the SOFC 20 It is possible to reduce the number of devices and the size or cost of the device, to lower the power consumption of the accessory components and to increase the power generation efficiency separately (for example, a radiator or a dilution air blower when the waste heat is not used).

«Second embodiment»

A fuel cell system 1 according to a second embodiment, with reference to 4 described. According to the second embodiment, there is a cooling air guide pipe 15 for guiding through the cooling fan 40 introduced cooling air to the Deckenperforationsabschnitt 13 inside the accessory chamber 12 arranged. In addition, form the exhaust pipe 30 and the cooling air guide pipe 15 a dual piping structure in which the exhaust duct pipe 30 is arranged inside and the cooling air guide tube 15 is arranged to the outside. As a result, it is possible to have the heat exchange efficiency (a cooling efficiency) between the exhaust gas from the SOFC 20 and the cooling air inside the accessory chamber 12 to improve.

It should be noted that the present invention is not limited to the embodiment discussed above and various modifications are possible. In the embodiments described above, sizes, shapes, functions, or the like of the elements illustrated in the accompanying drawings may be appropriately changed without being limited thereto as long as the results of the present invention can be obtained. In addition, various modifications may be possible without departing from the spirit and scope of the invention.

For example, in the above-mentioned embodiment, there is a case where the exhaust gas guide pipe 30 upwards over the ceiling perforation section 13 the accessory chamber 12 (the one in the ceiling chamber 60 is used) has been described. Alternatively, the exhaust pipe can 30 extend to the same height position as the Deckenperforationsabschnitt 13 the accessory chamber 12 or slightly below it (the exhaust pipe 30 can be inside the accessory chamber 12 stay without going to the ceiling chamber 60 to be introduced). Even in this case, the exhaust pipe 30 the exhaust from the SOFC 20 from the main aggregate chamber 11 via the accessory chamber 12 to the ceiling perforation section 13 to lead.

For example, in the above-mentioned embodiment, a case has been described where the first baffle or baffle 62 and the second baffle or baffle 63 inside the ceiling chamber 60 are arranged. Alternatively, the first baffle or baffle 62 and the second baffle or baffle 63 be omitted. The exhaust gas from the SOFC 20 passing through the exhaust pipe 30 is guided, and through the cooling fan 40 introduced cooling air can near the Deckenperforationsabschnitts 13 the accessory chamber 12 mixed and diluted by the ceiling chamber 60 is omitted.

For example, in the above-mentioned embodiment, a case where a solid oxide fuel cell (SOFC) is used as the fuel cell has been described. Alternatively, other types of fuel cells (for example, a polymer electrolyte fuel cell, a phosphoric acid fuel cell, or the like) may be used.

For example, in the above-mentioned embodiment, a case where a cooling fan is used as a radiator has been described. Alternatively, other types of coolers may be used as long as the cooling air can be introduced into the accessory chamber.

The fuel cell system according to the present invention is suitable for domestic, commercial or industrial applications.

LIST OF REFERENCE NUMBERS

1

The fuel cell system

10

housing unit

11

Main assembly chamber

12

Accessories chamber

13

Ceiling perforation section (accessory chamber outlet port)

14

opening

15

Cooling air guide tube

20

Solid oxide fuel cell (fuel cell) (SOFC)

30

Exhaust gas guide tube

40

Cooling fan (accessory chamber fan, radiator or cooling unit)

50

Waste heat recovery heat exchanger (hot water heat exchanger)

51

Waste heat recovery circulation line

51A

downstream pipe

51B

upstream line

60

Ceiling chamber (withdrawal channel)

61

Deduction port (last withdrawal port)

62

first baffle or guide plate

62A

opposite side

62B

Links page

62C

cavity

62D

opening

63

second baffle or guide plate

63A

opposite side

63B

Links page

63C

cavity

70

temperature detector

80

control unit

Claims (4)

A fuel cell system comprising: a main aggregate chamber in which a fuel cell is arranged; an accessory chamber in which a radiator for introducing a cooling air is arranged; a Deckenperforationsabschnitt disposed in the accessory chamber to externally remove the introduced through the radiator in the accessory chamber cooling air; an exhaust guide pipe protruding upward from the ceiling perforation section to guide an exhaust gas from the fuel cell from the main aggregate chamber via the accessory chamber to the ceiling perforation section; a first baffle arranged to surround the exhaust duct above the ceiling perforation section; and a second baffle arranged to face a tip of the exhaust duct above the ceiling perforation section. Fuel cell system after Claim 1 wherein the first and second baffle plates, when viewed in a plan view, have an essentially H-shape and are arranged so as to deviate from each other by a relative phase difference of 90 °. Fuel cell system after Claim 1 or 2 further comprising a cooling air guide pipe configured to guide the cooling air introduced into the accessory chamber to the ceiling perforation section, the exhaust guide pipe and the cooling air guide pipe having a dual piping structure in which the exhaust pipe is disposed inwardly and the cooling air guide pipe is outwardly disposed is. Fuel cell system after Claim 1 or 2 , further comprising: a temperature detector configured to detect an air temperature in the vicinity of the ceiling perforation section; and a control unit configured to control the radiator based on a detection result of the temperature detector.

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