JP2020136012A - Fuel cell system - Google Patents

Abstract

To reduce the concentration of carbon dioxide included in combustion exhaust gas exhausted from a fuel cell system during operation of the fuel cell system.SOLUTION: A housing exhaust port 31 for discharging combustion exhaust gas from an exhaust duct 29 to the outside of a housing 1 is covered with an exhaust cover 40 from the outside of the housing 1, and the combustion exhaust gas is caused to pass through a combustion exhaust gas path 43 provided inside the exhaust cover 40 and is discharged from an exhaust port 49. On the other hand, dilution air is sucked from a first opening 45, and is caused to pass through a dilution air flow path 42 provided inside the exhaust cover 40, and is discharged from a second opening 48 formed above the exhaust port 49. Further, a communicative hole for discharging the air in the housing 1 from the dilution air flow path 42 to the outside is provided in the dilution air flow path 42, and the air in the housing 1 is discharged to the outside as the dilution air, and therefore, the ventilation of the housing 1 can be promoted.SELECTED DRAWING: Figure 1

Description

The present invention relates to a fuel cell system, and more particularly to a fuel cell system that exhausts combustion exhaust gas to the outside of a housing.

In a conventional fuel cell system, electricity and heat are generated at the same time by chemically reacting a fuel gas containing hydrogen with an oxidant gas containing oxygen such as air, and the generated electricity is used as an external power load (for example,). It is a system that supplies electrical equipment used at home (for example, Patent Document 1).

FIG. 11 shows a configuration diagram of a conventional fuel cell system. The exhaust device 70 of the conventional fuel cell device (not shown) is attached so as to cover the housing exhaust port 72 of the housing 71. The exhaust gas discharged from the fuel cell device is configured to be discharged to the outside from the exhaust port 75 of the exhaust device 70 via the exhaust duct 73 connected to the housing exhaust port 72.

In addition, it is necessary to consider the case where the fuel cell system is installed not only outdoors but also in an apartment house. When installing a fuel cell system in an apartment house, a pipe space room or a veranda can be mentioned. There are few problems in the place where the balcony is installed, because it is considered to be installed outdoors. However, when the fuel cell system is installed in the pipe space room, it is considered to be installed indoors.

A configuration for installing a fuel cell system in a pipe space room of an apartment house has been studied (for example, Patent Document 2).

As shown in FIG. 12, the fuel cell system 80 is installed inside a pipe space chamber 82 separated by a structure such as a wall 81, and a door 83 is provided in front of the fuel cell system 80. ..

The housing 84 of the fuel cell system 80 is provided with an intake port (not shown) and an exhaust port 85. The door 83 is formed with openings (not shown) in accordance with the intake port and the exhaust port 85, and a frame 86 such as rubber is formed around the intake port and the exhaust port 85 so that the intake / exhaust gas does not leak to the surroundings. Is installed.

Japanese Unexamined Patent Publication No. 2012-209225 Japanese Unexamined Patent Publication No. 2011-258496

However, when the fuel cell system is installed in the pipe space chamber, the exhaust gas is not diluted by wind or the like.

In addition, the pipe space where the fuel cell system is installed is separated by structures such as walls and doors, and when combustion exhaust gas containing high-concentration carbon dioxide is discharged to the outside of the housing at a low flow velocity, the inside of the pipe space or It may stay in the common corridor and reduce the air quality.

Therefore, the configuration of Patent Document 2 is a system that controls the output of the fuel cell by detecting the temperature and the carbon monoxide concentration in the room where the fuel cell system is installed with a sensor. However, in the configuration of Patent Document 2, there is a possibility that the output of the fuel cell cannot be maintained at a desired value.

This disclosure is
A reforming unit that generates hydrogen-containing gas by the reforming reaction of the raw material gas,
A fuel cell that generates electricity using the hydrogen-containing gas and the oxidant gas,
A combustion unit that heats the reformed unit by burning a combustion gas composed of at least one of the raw material gas and the hydrogen-containing gas.
An exhaust duct for exhausting the combustion exhaust gas from the combustion part and
A housing that houses the reforming unit, the fuel cell, the combustion unit, and the exhaust duct.
A housing exhaust port provided on one side wall of the housing and exhausting the combustion exhaust gas to the outside from the exhaust duct,
The combustion exhaust gas derived from the housing exhaust port is diluted with air taken in from the outside and discharged to the outside.
The exhaust gas diluting part
An exhaust cover installed so as to cover the housing exhaust port from the outside of the housing,
Diluted exhaust gas exhaust port provided on the exhaust cover and
A dilution air flow path that sucks in external air from a first opening opened in one side wall of the housing and discharges the air to the outside through a second opening of the diluted exhaust gas exhaust port.
A communication hole for discharging the air in the housing from the dilution air flow path to the dilution air flow path, and
It is partitioned from the diluting air flow path, and includes a combustion exhaust gas flow path that discharges the combustion exhaust gas to the outside from the exhaust port of the diluted exhaust gas exhaust port via the space sandwiched between the exhaust cover and the one side wall. It also provides a fuel cell system.

According to the technique of the present disclosure, the combustion exhaust gas from the combustion part is introduced into the exhaust gas diluting part, and the combustion exhaust gas is diluted and exhausted by the air supplied from the diluting air flow path provided in the exhaust gas diluting part. Therefore, the carbon dioxide concentration in the combustion exhaust gas can be lowered more reliably, and the safety can be improved. In addition, by adding the dilution air to the ventilation air inside the housing and taking in from the outside of the housing, the flow rate of the ventilation air inside the housing is suppressed to maintain the heat balance inside the housing, and the fuel cell system. Can stabilize the operation of.

Configuration diagram of the fuel cell system according to the first embodiment of the present invention Front view of the fuel cell system according to the first embodiment of the present invention Configuration diagram of the exhaust cover according to the first embodiment of the present invention Configuration diagram of the fuel cell system according to the second embodiment of the present invention Front view of the fuel cell system according to the second embodiment of the present invention Configuration diagram of the exhaust cover according to the second embodiment of the present invention Configuration diagram of the fuel cell system according to the third embodiment of the present invention Front view of the fuel cell system according to the third embodiment of the present invention Configuration diagram of the exhaust cover according to the third embodiment of the present invention Bulb assembly block diagram Configuration diagram of a conventional household fuel cell system Configuration diagram when a conventional household fuel cell is installed on a pipe shaft

(Knowledge on which this disclosure is based)
As shown in FIG. 11, in the fuel cell system disclosed in Patent Document 2, the intake port (not shown) and the exhaust port 85 provided in the housing 84 of the fuel cell system 80 are provided in the door 83. It is arranged to face the opening (not shown).

However, although the exhaust gas discharged from the fuel cell system is discharged to the outside of the pipe space chamber through the opening provided in the door, it does not have a means for reducing the carbon dioxide concentration in the combustion exhaust gas. Therefore, when the combustion exhaust gas is discharged from the housing of the fuel cell system at a low flow velocity, it may stay in the pipe space room, the common corridor, or the like.

As a result of sharp examination, the inventor of the present application has configured the combustion exhaust gas discharged from the housing in which the fuel cell system is housed to be exhausted along with the air taken in from the outside of the housing to reduce the carbon dioxide concentration. We found that it can be reduced efficiently.

In addition, by adding a configuration that supplies air from outside the housing, it is possible to maintain the temperature field near the fuel cell stack and the reforming part by suppressing fluctuations in the airflow inside the housing, which is provided for fuel cell power generation. I thought that the impact could be suppressed.
(Summary of one aspect relating to this disclosure)
The fuel cell system according to the first aspect of the present disclosure is
A reforming unit that generates hydrogen-containing gas by the reforming reaction of the raw material gas,
A fuel cell that generates electricity using the hydrogen-containing gas and the oxidant gas,
A combustion unit that heats the reformed unit by burning a combustion gas composed of at least one of the raw material gas and the hydrogen-containing gas.
An exhaust duct for exhausting the combustion exhaust gas from the combustion part and
A housing that houses the reforming unit, the fuel cell, the combustion unit, and the exhaust duct.
A housing exhaust port provided on one side wall of the housing and exhausting the combustion exhaust gas to the outside from the exhaust duct,
The combustion exhaust gas derived from the housing exhaust port is diluted with air taken in from the outside and discharged to the outside.
The exhaust gas diluting part
An exhaust cover installed so as to cover the housing exhaust port from the outside of the housing,
Diluted exhaust gas exhaust port provided on the exhaust cover and
A dilution air flow path that sucks in external air from a first opening opened in one side wall of the housing and discharges the air to the outside through a second opening of the diluted exhaust gas exhaust port.
A communication hole for discharging the air in the housing from the dilution air flow path to the dilution air flow path, and
It is provided with a combustion exhaust gas flow path which is partitioned from the dilution air flow path and discharges the combustion exhaust gas to the outside from the exhaust port of the diluted exhaust gas exhaust port via the space sandwiched between the exhaust cover and the one side wall. It is a dilution.

According to the fuel cell system of the first aspect, even if the combustion exhaust gas containing a high concentration of carbon dioxide is generated in the combustion part during the operation of the fuel cell system, the combustion exhaust gas and the air having a low carbon dioxide concentration are diluted. It is possible to merge and mix at the exhaust gas exhaust port to dilute the carbon dioxide concentration and discharge it.

Further, since the structure is such that the air outside the housing is sucked from the first opening, the air around the fuel cell system is installed and the combustion exhaust gas can be diluted.

In addition, by merging and discharging the combustion exhaust gas and air, the discharge flow velocity of the combustion exhaust gas discharged from the fuel cell system can be increased, and the reach of the discharged combustion exhaust gas can be increased, which is shared. It is possible to suppress staying in the corridor. Therefore, it is possible to suppress deterioration of air quality in common corridors and the like.

Further, since the air inside the housing is exhausted to the outside as dilution air, ventilation inside the housing can be promoted.

The fuel cell system according to the second aspect is provided in the communication hole, particularly in the fuel cell system of the first aspect, and the flow rate at which the air in the housing is discharged from the communication hole to the dilution air flow path can be adjusted. It is equipped with various flow rate adjusting means.

According to the fuel cell system of the second aspect, since the flow rate for discharging the air inside the housing from the communication hole can be adjusted, the design likelihood of the communication hole is increased.

The fuel cell system according to the third aspect is arranged in the order of the second opening and the exhaust port from above in the diluted exhaust gas exhaust port, particularly in the fuel cell system of the first aspect or the second aspect. ..

According to the fuel cell system of the third aspect, the temperature is increased by arranging the second opening, which is the outlet of air having a temperature lower than the temperature of the combustion exhaust gas, above the exhaust port, which is the outlet of the combustion exhaust gas. It is possible to suppress the upward winding of the combustion exhaust gas along the low air flow. Therefore, the diluted exhaust gas can be discharged farther toward the discharge direction of the exhaust port.

The fuel cell system according to the fourth aspect, particularly in the fuel cell system of the first aspect or the second aspect, the first opening is provided inside the exhaust gas diluting portion and opens toward the diluted exhaust gas exhaust port. In the diluted exhaust gas exhaust port, the first opening, the second opening, and the exhaust port are arranged in this order from above.

According to the fuel cell system of the fourth aspect, the first opening, the second opening, and the exhaust port are opened inside the diluted exhaust gas exhaust port. With this configuration, it is possible to compactly design a dilution air flow path that sucks in external air from the first opening and discharges the air to the outside through the second opening that opens toward the diluted exhaust gas exhaust port. ..

Further, in the diluted exhaust gas exhaust port, the first opening, the second opening, and the exhaust port are arranged in this order from the top. By arranging the second opening that discharges the air for dilution between the discharge port that discharges the combustion exhaust gas and the first opening that sucks in air, the combustion exhaust gas discharged from the exhaust port is shortcut to the first opening. Can be prevented. As a result, the combustion exhaust gas can be efficiently diluted.

The fuel cell system according to the fifth aspect is provided with an exhaust stack extending from the inner peripheral portion of the diluted exhaust gas exhaust port, particularly in the fuel cell systems of the first to fourth aspects.

According to the fuel cell system of the fifth aspect, when the fuel cell system is installed in the pipe space room or the like, the diluted combustion exhaust gas is discharged by ejecting the exhaust pipe from the opening formed in the door of the pipe space room or the like. It can be discharged to the outside of the installation space.

The fuel cell system according to the sixth aspect is a fuel cell system according to the first to fifth aspects in which a fan is provided in the dilution air flow path.

According to the fuel cell system of the sixth aspect, it is possible to secure the flow rate of air for dilution even when there is no wind in the vicinity where the fuel cell system is installed.

In the fuel cell system according to the seventh aspect, particularly in the fuel cell system according to the sixth aspect, the rotation speed of the fan is the amount of power generated by the fuel cell, the amount of combustion air supplied by the combustion unit, and the combustion gas. It is controlled according to at least one piece of information on the supply amount of.

According to the fuel cell system of the seventh aspect, the carbon dioxide concentration in the diluted exhaust gas is appropriately controlled by controlling the rotation speed of the fan according to the emission amount of the combustion exhaust gas and controlling the flow rate of the air for dilution. be able to. In addition, exhaust gas management can be automated by predicting the amount of combustion exhaust gas emitted based on the amount of power generated by the fuel cell, the amount of combustion air supplied by the combustion unit, or the amount of combustion gas supplied. ..

The fuel cell system according to the eighth aspect is a fuel cell system according to the first to seventh aspects in which a part of the dilution air flow path is provided inside the housing.

According to the fuel cell system of the eighth aspect, the first opening which is the suction port of the air for dilution and the second opening which is the discharge port of the air for dilution are provided on one side wall of the housing. Therefore, it is necessary to change the traveling direction of the air flow by 180 °. By providing a part of the dilution air flow path inside the housing, the bending part of the dilution air flow path becomes steep, which increases the flow path resistance and suppresses the deceleration of the air flow velocity. it can.

The fuel cell system according to the ninth aspect is the condensed water generated from the combustion exhaust gas formed in the combustion exhaust gas flow path and led out into the combustion exhaust gas flow path, particularly in the fuel cell systems of the first to eighth aspects. Is provided with a drain hole for discharging the fuel from the exhaust cover.

According to the fuel cell system of the ninth aspect, the combustion exhaust gas is cooled in the exhaust cover, and the water vapor in the exhaust gas becomes condensed water and accumulates at the bottom of the exhaust cover. Here, the condensed water due to the condensation of water vapor in the exhaust gas is acidic, and the exhaust cover is liable to be corroded. On the other hand, by providing the exhaust cover with a drain discharge portion for discharging condensed water, it is possible to suppress exposure of the exhaust cover to condensed water and prevent corrosion of the exhaust cover.
(Embodiment 1)
Hereinafter, the fuel cell system according to the first embodiment of the present invention will be described with reference to the drawings. The present invention is not limited to this embodiment.
(Fuel cell system configuration and operation)
As shown in FIGS. 1, 2, and 3, the fuel cell system 100 according to the first embodiment of the present invention includes a housing 1, a fuel cell 3, a reforming unit 4, and a combustion unit 5. The fuel cell 3, the reforming unit 4, and the combustion unit 5 are housed inside the housing 1. The housing 1 has a vertically long rectangular parallelepiped shape. A plurality of legs 2 are attached to the lower surface of the bottom surface of the housing 1.

The reforming unit 4 heats an evaporator (not shown) with the heat supplied from the combustion unit 5 to generate steam from the water supplied from the tank 6 via the first water circuit 10. Then, the steam and the raw material gas supplied from the raw material gas supply path 11 are subjected to a steam reforming reaction (CH ₄ + H ₂ O → CO + 3 H ₂ ) by the action of the reforming catalyst to generate a hydrogen-containing gas.

The raw material gas supply path 11 is branched, and the raw material gas is supplied to the combustion unit 5 and the reforming unit 4. The raw material gas is, for example, a hydrocarbon such as city gas or LP gas (liquefied petroleum gas).

Further, the combustion unit 5 is provided between the fuel cell 3 and the reforming unit 4. In the combustion unit 5, the fuel off gas and the raw material gas from the fuel cell 3 are burned by the oxidant off gas and the combustion air from the fuel cell 3, and the reforming unit and the evaporating unit are heated by the combustion gas.

The raw material gas supply path 11 is connected to an external raw material gas supply source (not shown) of the housing 1 via a connector 16 attached to a through hole formed in the bottom surface of the housing 1. The connector 16 is made of metal.

The hydrogen-containing gas generated in the reforming unit 4 is supplied to the fuel cell 3 via the hydrogen-containing gas supply path 20. The fuel cell 3 uses an oxidant gas (air) and a hydrogen-containing gas to generate electric power. The fuel off-gas that was not used for power generation in the fuel cell 3 is supplied to the combustion unit 5 through the off-gas path 19. Here, the fuel cell 3 is, for example, a polymer electrolyte fuel cell or a solid oxide fuel cell. Hot water is generated by the exhaust heat of the fuel cell 3. The generated hot water is stored in a hot water storage tank (not shown).

The fuel cell system 100 includes a second water circuit 12, a heat exchanger 13, and a heat recovery channel 14. The second water circuit 12 is connected to the fuel cell 3. The second water circuit 12 is a cooling water circuit in which cooling water for cooling the fuel cell 3 circulates. A tank 15 is provided in the second water circuit 12.

The heat recovery water channel 14 is a flow path for recovering the exhaust heat of the fuel cell 3. The heat recovery channel 14 includes heat recovery pipes 14a and 14b. The heat recovery pipes 14a and 14b are connected to the heat exchanger 13, respectively. The heat recovery pipe 14a constitutes a downstream portion of the heat recovery water channel 14. The heat recovery pipe 14b constitutes an upstream portion of the heat recovery water channel 14. The heat recovery pipe 14a is a pipe for guiding the water heated in the heat exchanger 13 to the hot water storage tank. The heat recovery pipe 14b is a pipe for supplying the water to be heated in the heat exchanger 13 to the heat exchanger 13. The heat recovery pipes 14a and 14b are metal pipes such as stainless steel pipes. The first water circuit 10, the second water circuit 12, the heat exchanger 13, the heat recovery water channels 14 and the tanks 6 and 15 are also inside the housing 1. It is located in.

The heat recovery pipe 14a reaches from the upper surface side of the bottom surface (inside the housing 1) to the lower surface side of the bottom surface through a through hole formed in the bottom surface of the housing 1. Specifically, the high temperature side connector 17 is attached to the through hole formed on the bottom surface. The heat recovery pipe 14a extends from the inside of the housing 1 to the outside via the high temperature side connector 17, and can be connected to the high temperature water inlet of the hot water storage tank. Similarly, the heat recovery pipe 14b reaches from the upper surface side of the bottom surface to the lower surface side of the bottom surface through a through hole formed in the bottom surface of the housing 1. Specifically, the low temperature side connector 18 is attached to the through hole formed in the bottom surface. The heat recovery pipe 14b extends from the inside of the housing 1 to the outside via the low temperature side connector 18, and can be connected to the low temperature water outlet of the hot water storage tank or the city water pipe. The high temperature side connector 17 and the low temperature side connector 18 are made of resin or metal.

The fuel cell system includes a circuit housing 21 and an electronic circuit board 22. The circuit housing 21 is arranged inside the housing 1. The circuit housing 21 is made of an insulating material such as resin. Various electronic components such as a controller 22a and an inverter 22b are mounted on the electronic circuit board 22. The controller 22a is a device that controls control targets such as a fuel cell 3, a reforming unit 4, a combustion unit 5, and various auxiliary devices (not shown). The controller 22a is composed of, for example, a DSP (Digital Signal Processor) including an A / D conversion circuit, an input / output circuit, an arithmetic circuit, a storage device, and the like. The inverter 22b is a device for converting the DC output of the fuel cell 3 into an AC output.
(Intake / exhaust configuration inside the housing)
The circuit housing 21 has a rectangular parallelepiped shape that opens in the horizontal direction (toward one side wall 1a of the housing 1). The circuit housing 21 is attached to the one side wall 1a from the inside of the housing 1 so that the opening of the circuit housing 21 is closed by the one side wall 1a of the housing 1, and the ventilation duct 25 is formed. That is, it plays the role of a partition wall that divides the internal space of the circuit housing 21 and the housing 1 into a plurality of parts. An intake port 24 is provided in the lower part of the ventilation duct 25. An exhaust port 27 is provided above the ventilation duct 25. The role of the intake port 24 is to communicate the outside of the housing 1 with the inside of the ventilation duct 25. The role of the exhaust port 27 is to communicate the inside of the ventilation duct 25 with the inside of the housing 1 excluding the ventilation duct 25. The electronic circuit board 22 and the control unit 28 described later are arranged in the ventilation duct 25.

One side wall 1a of the housing 1 is provided with an intake port 23 including a plurality of louvers. The intake port 23 is located below the intake port 24 of the circuit housing 21 in the vertical direction. The role of the intake port 23 is to communicate the outside and the inside of the housing 1 via the ventilation duct 25. The electronic circuit board 22 is arranged in the circuit housing 21. The housing 1 includes a hood 26. The hood 26 is attached to one side wall 1a of the housing 1 from the inside of the housing 1, and integrally covers the lower portion of the circuit housing 21 and the intake port 23 of the one side wall 1a. The hood 26 forms an air flow path from the intake port 23 of the one side wall 1a to the intake port 24 of the circuit housing 21. With such a configuration, it is possible to prevent dust, rainwater, and the like from being sucked into the ventilation duct 25 and adversely affecting the electronic circuit board 22.

In the ventilation duct 25, the air is heated by the exhaust heat of electronic parts such as the inverter 22b. The warmed air is discharged to the outside of the ventilation duct 25 through the exhaust port 27, and changes to the air flow inside the housing 1. The air passes around the reforming section 4 and the like, and contributes to the formation of the temperature field around the fuel cell 3.

A ventilation port 53 is provided on one side wall 1a of the housing 1. The role of the ventilation port 53 is to communicate the inside of the housing 1 with the outside of the housing 1. Air is discharged from the inside of the housing 1 to the outside through the ventilation port 53. In the present embodiment, the ventilation port 53 is located below the intake port 24 in the vertical direction. According to such a positional relationship, the air taken into the housing 1 is smoothly guided to the space below the housing 1.

Further, the ventilation port 53 includes a plurality of louvers. The housing 1 further includes a hood 51. The hood 51 is attached to one side wall 1a from the inside of the housing 1, and integrally covers the ventilation port 53 and the ventilation fan 52 described later. The hood 51 forms an air flow path from the ventilation fan 52 to the ventilation port 53. According to such a structure, it is possible to prevent dust, rainwater, and the like from entering the inside of the housing 1 and adversely affecting the parts arranged inside the housing 1. The ventilation fan 52 may be attached to the hood 51.

In the present embodiment, the ventilation port 53 is located at substantially the same height as the intake port 23 in the vertical direction. In other words, the ventilation port 53 and the intake port 24 overlap in the vertical direction. The closer the ventilation port 53 is to the bottom surface of the housing 1, the longer the moving distance of the air warmed by the electronic component such as the inverter 22b is.

Further, the fuel cell system 100 includes an intake fan 24a and a ventilation fan 52. The intake fan 24a is arranged at or near the intake port 24. The intake fan 24a is a fan for supplying air outside the housing 1 to the inside of the housing 1 through the intake port 24. The ventilation fan 52 is a fan for discharging the air inside the housing 1 to the outside of the housing 1 through the ventilation port 53. When at least one of the intake fan 24a and the ventilation fan 52 is provided, the air warmed by the electronic components such as the inverter 22b is efficiently supplied to the inside of the housing 1, circulated, and then to the outside of the housing 1. Can be discharged.

In this way, a stable temperature field is formed around the fuel cell 3 and the reforming unit 4 arranged inside the housing 1.
(Combustion exhaust gas is diluted and exhausted)
Next, a method of discharging the combustion exhaust gas discharged from the combustion unit 5 will be described.

The combustion exhaust gas discharged from the combustion unit 5 is guided to the diffusion duct unit 32 through the exhaust duct 29. The diffusion duct portion 32 is connected to a housing exhaust port 31 formed on one side wall 1a of the housing 1. The diffusion duct portion 32 is attached to one side wall 1a from the inside of the housing 1, and integrally covers the housing exhaust port 31. The diffusion duct portion 32 leads out the combustion exhaust gas toward the housing exhaust port 31. The diffusion duct portion 32 has a larger cross-sectional area of the flow path of the combustion exhaust gas than the exhaust duct 29. As a result, the combustion exhaust gas derived from the exhaust duct 29 diffuses in the diffusion duct portion 32, the flow velocity decreases, and the water vapor contained in the combustion exhaust gas is promoted to condense.

The condensed water generated by condensing the water vapor contained in the combustion exhaust gas in the diffusion duct portion 32 is discharged from the drainage portion 33 to the outside of the housing 1 via a drainage member (not shown). The water vapor in the exhaust gas condenses into condensed water, which accumulates at the bottom of the diffusion duct portion 32. Here, the condensed water due to the condensation of water vapor in the exhaust gas is acidic, and the diffusion duct portion 32 is likely to be corroded. On the other hand, by providing the diffusion duct portion 32 with a drainage portion 33 for discharging condensed water, it is possible to suppress exposure of the diffusion duct portion 32 to the condensed water and prevent corrosion of the diffusion duct portion 32. ..

As shown in FIG. 1, a part of the diffusion duct portion 32 may be configured to protrude to the outside of the housing 1. With such a configuration, the combustion exhaust gas led out to the diffusion duct portion 32 is further cooled, and it is possible to promote the condensation of the water vapor contained in the combustion exhaust gas.

Next, the configuration of the exhaust gas diluting unit 90 will be described. An exhaust cover 40 is attached to one side wall 1a of the housing 1 so as to cover the housing exhaust port 31 from the outside. The exhaust cover 40 is formed with a diluted exhaust gas exhaust port 44 that discharges diluted combustion exhaust gas to the outside. In the space surrounded by the exhaust cover 40 and the one side wall 1a, the combustion exhaust gas is discharged to the outside from the dilution air flow path 42 and the housing exhaust port 31 described later by the partition member 41 via the dilution exhaust gas exhaust port 44. It is separated from the combustion exhaust gas flow path 43. The diluted exhaust gas exhaust port 44 is also separated into a second opening 48 that communicates with the dilution air flow path 42 and an exhaust port 49 that communicates with the combustion exhaust gas flow path 43.

The role of the combustion exhaust gas flow path 43 is to guide the combustion exhaust gas discharged from the housing exhaust port 31 to the exhaust port 49 via the diffusion duct portion 32.

In the present embodiment, the dilution air flow path 42 is composed of a first dilution air flow path 42a provided inside the exhaust cover 40 and a second dilution air flow path 42b provided inside the housing 1. ing.

As shown in FIGS. 1, 2, and 3, one side wall 1a of the housing 1 has a first opening 45 for guiding air from the outside of the housing 1 to the air flow path 42b for second dilution, and a first opening 45. (Ii) A third opening 46 for discharging air to the first dilution air flow path 42a formed inside the exhaust cover 40 is formed through the dilution air flow path 42b. The third opening 46 is covered with an exhaust cover 40 from the outside of the one side wall 1a and communicates with the first dilution air flow path 42a. Further, the third opening 46 is covered with a second dilution air flow path 42b from the inside of the one side wall 1a. That is, air is taken into the second dilution air flow path 42b from the first opening 45, passes through the third opening 46, and is discharged from the second opening 48 through the first dilution air flow path 42a.

FIG. 3A is a three-dimensional configuration diagram showing the configuration of the exhaust cover 40, and FIG. 3B is a three-dimensional sectional view showing the configuration of the first dilution air flow path 42a and the second dilution air flow path 42b. It was shown to.

With such a configuration, even if combustion exhaust gas containing a high concentration of carbon dioxide is generated in the combustion unit 5 during operation of the fuel cell system 100, it is guided from the combustion exhaust gas flow path 43 to the exhaust port 49. The combustion exhaust gas and the air having a low carbon dioxide concentration guided from the diluting air flow path 42 to the second opening 48 can be merged and mixed at the diluted exhaust gas exhaust port 44 to dilute the carbon dioxide concentration and discharge. It will be possible.

Further, since the structure is such that the air outside the housing 1 is sucked from the first opening 45, even when the fuel cell system 100 is installed in the pipe space chamber, the surrounding air can be sucked in to dilute the combustion exhaust gas. it can.

Further, by adopting a configuration in which the combustion exhaust gas and air are merged and discharged, the discharge flow rate of the combustion exhaust gas discharged from the fuel cell system 100 can be increased, and the reach of the discharged combustion exhaust gas can be increased. It is possible to prevent staying in a common corridor. Therefore, it is possible to suppress deterioration of air quality in common corridors and the like.

Further, by adding a configuration in which the dilution air is sucked not only from the inside of the housing 1 but also from the outside of the housing 1, the flow rate of the ventilation air from the inside of the housing 1 can be suppressed, and the inside of the housing 1, especially The thermal balance around the reforming unit 4 and the fuel cell 3 can be maintained, and the operation of the fuel cell system 100 can be stabilized.

Further, the first opening 45 and the diluted exhaust gas exhaust port 44 (second opening 48, discharge port 49) are opened in substantially the same direction. Therefore, even if wind blows toward the diluted exhaust gas exhaust port 44 during operation of the fuel cell system 100, the first opening 45 and the diluted exhaust gas exhaust port 44 (second opening 48, discharge port 49) are opened. The applied wind pressure becomes the same. Therefore, it is possible to prevent the combustion exhaust gas from flowing into the housing 1 from the exhaust port 49.

In the present embodiment, the first opening 45 for taking in the diluted air and the diluted exhaust gas exhaust port 44 for discharging the diluted combustion exhaust gas can be formed apart from each other. Therefore, it is possible to prevent the combustion exhaust gas from being taken in as dilution air from the first opening 45 as a shortcut.

Further, in the present embodiment, the second dilution air flow path 42b is provided inside the housing 1. The first opening 45, which is a suction port for the air for dilution, and the third opening 46, which leads out the air for dilution to the exhaust cover 40 side, are provided on one side wall 1a of the housing 1. Therefore, it is necessary to change the traveling direction of the air flow by 180 °. By providing a part of the dilution air flow path 42 inside the housing 1, the bending portion of the dilution air flow path 42 becomes steep, so that the flow path resistance increases and the air flow velocity slows down. Can be suppressed.

Further, in the diluted exhaust gas exhaust port 44, the second opening 48 and the exhaust port 49 are arranged in this order from the top.

FIG. 3A is a three-dimensional configuration diagram showing the configuration of the exhaust cover 40, and FIG. 3B is a three-dimensional sectional view showing the configuration of the first dilution air flow path 42a and the second dilution air flow path 42b. It was shown to.

With such a configuration, the second opening 48, which is an outlet for air whose temperature is lower than the temperature of the combustion exhaust gas, is arranged above the exhaust port 49, which is the outlet for the combustion exhaust gas. It is possible to suppress the upward winding of the combustion exhaust gas F ₁ along the low air flow F ₂ . Therefore, the diluted exhaust gas can be discharged farther toward the discharge direction of the diluted exhaust gas exhaust port 44.

Further, the fuel cell system 100 includes a fan 47 in the dilution air flow path 42. The fan 47 is installed so as to cover the third opening 46 from the inside of the one side wall 1a. As a result, the air outside the housing 1 can be taken into the dilution air flow path 42 through the first opening 45. The rotation speed of the fan 47 is controlled by the control unit 28.

In this way, by taking the air outside the housing 1 into the dilution air flow path 42 as the dilution air by the fan 47, even if there is no wind in the vicinity where the fuel cell system 100 is installed, the dilution is performed. It is possible to secure the flow rate of air for use.

In addition, during non-steady operation such as start-up operation of the fuel cell 3, the combustion state of the combustion unit 5 may fluctuate due to load fluctuation, and the amount of exhaust gas may fluctuate. Fluctuations in the emission amount of the combustion exhaust gas can be detected from at least one information of the power generation amount of the fuel cell 3, the supply amount of the combustion air supplied by the combustion unit 5, and the supply amount of the raw material gas, and the emission amount can also be predicted. Therefore, the control unit 28 controls the rotation speed of the fan 47 based on at least one information of the power generation amount of the fuel cell 3, the supply amount of the combustion air supplied by the combustion unit 5, and the supply amount of the raw material gas. It may be configured.

With such a configuration, it is possible to properly control the carbon dioxide concentration in the diluted exhaust gas by controlling the rotation speed of the fan according to the emission amount of the combustion exhaust gas and controlling the flow rate of the air for dilution. it can. In addition, exhaust gas management can be automated by predicting the amount of combustion exhaust gas emitted based on the amount of power generated by the fuel cell, the amount of combustion air supplied by the combustion unit, or the amount of combustion gas supplied. ..

Further, an exhaust pipe 50 extending from the inner peripheral portion of the diluted exhaust gas exhaust port 44 may be provided. The partition member 41 may extend to the inside of the exhaust stack 50. With such a configuration, the decrease in the speed at which the diluting air and the combustion exhaust gas pass through the exhaust stack 50 is suppressed, and the diluted exhaust gas is discharged farther toward the discharge direction of the diluted exhaust gas exhaust port 44. be able to.

Further, with such a configuration, when the fuel cell system 100 is installed in the pipe space chamber or the like, the exhaust pipe is ejected from the opening formed in the door of the pipe space chamber or the like to dilute the combustion exhaust gas. Can be discharged toward the outside of the installation space.

Further, even after the combustion exhaust gas is discharged to the combustion exhaust gas flow path 43 provided inside the exhaust cover 40, the condensation of water vapor in the combustion exhaust gas continues to occur. In the present embodiment, the combustion exhaust gas flow path 43 is provided below, and a part thereof communicates with the diffusion duct portion 32 protruding to the outside of the housing 1. Further, as shown in FIG. 1, by configuring the bottom of the exhaust cover 40 to be inclined toward the diffusion duct portion 32, the condensed water collected in the combustion exhaust gas flow path 43 is collected in the diffusion duct portion 32 and drained. It can be discharged to the outside of the housing 1 from the unit 33 via a drainage member (not shown). Here, the condensed water due to the condensation of water vapor in the exhaust gas is acidic, and the exhaust cover 40 is liable to be corroded. With such a configuration, it is possible to prevent the exhaust cover 40 from being exposed to condensed water and to prevent corrosion of the exhaust cover 40.

In the present embodiment, the first opening 45 is formed on one side wall 1a of the housing 1 to which the exhaust cover 40 is attached, but it may be formed on the other side wall of the housing 1.
(Structure that discharges the air inside the housing to the dilution air flow path)
Generally, in a fuel cell system, the temperature inside the housing is detected and the control unit limits the operation permission of the fuel cell system to ensure the stability of fuel cell power generation, and the water temperature and accessories in a high temperature environment. The temperature rise of the fuel cell is suppressed.

In the present embodiment, the air inside the housing 1 is discharged to the outside through the communication hole 91 formed in the dilution air flow path 42 (42b).

As shown in FIGS. 1 and 3B, a communication hole 91 is formed on one wall surface of the dilution air flow path 42b. The air inside the housing 1 is discharged to the outside of the housing 1 from the second dilution air flow path 42b through the communication hole 91. With such a configuration, ventilation inside the housing 1 is promoted.

Further, the flow rate adjusting means can be provided in the communication hole 91. In the following description, as an example, a case where the valve assembly 93 shown in FIG. 10 is used as the flow rate adjusting means will be described.

FIG. 10 shows the configuration of the valve assembly 93, which is an example of the opening / closing means. The valve assembly 93 is provided on the side wall of the second dilution air flow path 42b, and has a function of adjusting the flow rate of the air flowing out from the inside of the housing 1 to the second dilution air flow path 42.

The valve assembly 93 is mainly composed of a housing 94 and a butterfly valve 95. A communication hole 91 is formed in the housing 94, and the butterfly valve 95 is rotatable with the valve shaft 97 inserted in the shaft hole 96. The opening degree of the communication hole 91 can be adjusted by controlling the rotation of the valve shaft 97 via an opening / closing degree adjusting unit (not shown) and changing the posture of the butterfly valve 95.

When the valve assembly 93 is installed in the communication hole 91, for example, the control unit 28 controls an open / close degree adjusting unit (not shown), and the valve assembly 93 is discharged from the inside of the housing 1 to the second dilution air flow path through the communication hole 91. The air flow rate can be adjusted. Therefore, the design likelihood of the communication hole 91 can be increased.

Further, the adjustment of the air flow rate by the valve assembly 93 is also effective for adjusting the internal temperature of the housing 1. The temperature detection unit 97 in FIG. 1 can directly or indirectly detect the internal temperature of the housing 1. For example, when the detection temperature of the temperature detection unit 97 exceeds a predetermined temperature, the opening degree of the valve assembly 93 is increased to increase the air flow rate discharged from the inside of the housing 1 to the second dilution air flow path 42b. As a result, the effect of promoting ventilation inside the housing 1 and lowering the temperature inside the housing 1 can be obtained.

The flow rate of the air discharged from the inside of the housing 1 can also be adjusted by arbitrarily controlling the opening degree of the valve assembly 93, the rotation speeds of the ventilation fan 52, the fan 47, and the intake fan 24a. ..

As a result, when the internal temperature of the housing 1 exceeds a predetermined temperature, the fuel cell system 100 promotes ventilation inside the housing 1, so that a malfunction of the fuel cell system 100 can be avoided.

In the present embodiment, the temperature detection unit 97 is arranged near the bottom of the housing 1, but the present invention is not limited to this. It may be arranged in the vicinity of a portion to be monitored, for example, the combustion unit 5 or the fuel cell 3.

Further, in the fuel cell system 100, when the ventilation inside the housing 1 is not sufficiently ventilated due to the failure of the ventilation fan 52, the fuel cell system 100 is molded from the communication hole 91 provided in the dilution air flow path 42 instead of the ventilation fan 52. Since the air inside the body 1 can be discharged, a malfunction of the fuel cell system 100 can be avoided.
(Embodiment 2)
The fuel cell system 101 according to the second embodiment has the same basic configuration as the fuel cell system 100 according to the first embodiment, but has a first opening 45, which is a suction port for dilution air, formed in the exhaust cover 40. Is different. Therefore, the same parts as those operated by the fuel cell system 100 according to the embodiment are designated by the same reference numerals, duplicate description is omitted, and a configuration in which combustion exhaust gas is diluted and exhausted will be described.
(Combustion exhaust gas is diluted and exhausted)
A method of discharging the combustion exhaust gas discharged from the combustion unit 5 will be described with reference to FIGS. 4, 5 and 6.

The combustion exhaust gas discharged from the combustion unit 5 is guided to the diffusion duct unit 32 through the exhaust duct 29. The diffusion duct portion 32 is connected to a housing exhaust port 31 formed on one side wall 1a of the housing 1. The diffusion duct portion 32 is attached to one side wall 1a from the inside of the housing 1, and integrally covers the housing exhaust port 31. The diffusion duct portion 32 leads out the combustion exhaust gas toward the housing exhaust port 31. The diffusion duct portion 32 has a larger cross-sectional area of the flow path of the combustion exhaust gas than the exhaust duct 29. As a result, the combustion exhaust gas derived from the exhaust duct 29 diffuses in the diffusion duct portion 32, the flow velocity decreases, and the water vapor contained in the combustion exhaust gas is promoted to condense.

The condensed water generated by condensing the water vapor contained in the combustion exhaust gas in the diffusion duct portion 32 is discharged from the drainage portion 33 to the outside of the housing 1 via a drainage member (not shown). The water vapor in the exhaust gas condenses into condensed water, which accumulates at the bottom of the diffusion duct portion 32. Here, the condensed water due to the condensation of water vapor in the exhaust gas is acidic, and the diffusion duct portion 32 is likely to be corroded. On the other hand, by providing the diffusion duct portion 32 with a drainage portion 33 for discharging condensed water, it is possible to suppress exposure of the diffusion duct portion 32 to the condensed water and prevent corrosion of the diffusion duct portion 32. ..

It should be noted that a part of the diffusion duct portion 32 may be configured to protrude to the outside of the housing 1 as shown in FIG. With such a configuration, the combustion exhaust gas led out to the diffusion duct portion 32 is further cooled, and it is possible to promote the condensation of the water vapor contained in the combustion exhaust gas.

Next, the configuration of the exhaust gas diluting unit 90 will be described. An exhaust cover 40 is attached to one side wall 1a of the housing 1 so as to cover the housing exhaust port 31 from the outside. The exhaust cover 40 is formed with a diluted exhaust gas exhaust port 44 that discharges diluted combustion exhaust gas to the outside. In the space surrounded by the exhaust cover 40 and the one side wall 1a, the combustion exhaust gas is discharged to the outside from the dilution air flow path 42 and the housing exhaust port 31 described later by the partition member 41 via the dilution exhaust gas exhaust port 44. It is separated from the combustion exhaust gas flow path 43. The diluted exhaust gas exhaust port 44 is also separated into a second opening 48 that communicates with the dilution air flow path 42 and an exhaust port 49 that communicates with the combustion exhaust gas flow path 43.

The role of the combustion exhaust gas flow path 43 is to guide the combustion exhaust gas discharged from the housing exhaust port 31 to the exhaust port 49 via the diffusion duct portion 32.

In the present embodiment, the dilution air flow path 42 is composed of a first dilution air flow path 42a provided inside the exhaust cover 40 and a second dilution air flow path 42b provided inside the housing 1. ing.

As shown in FIG. 4, a first opening 45 for guiding air from the outside of the housing 1 to the second dilution air flow path 42b is formed on the side surface of the exhaust cover 40. A fourth opening 60 (corresponding to the first opening 45 of the first embodiment) for introducing air into the second dilution air flow path 42b is formed on one side wall 1a of the housing 1. The dilution air passes through the dilution air flow path 42 installed inside the housing 1 from the fourth opening 60, and is formed inside the exhaust cover 40 from the third opening 46 formed in the one side wall 1a. It is discharged to the air flow path 42a for dilution. The third opening 46 and the fourth opening 60 are covered with an exhaust cover 40 from the outside of the one side wall 1a and communicate with the first dilution air flow path 42a. Further, the third opening 46 and the fourth opening 60 are covered with a second dilution air flow path 42b from the inside of the one side wall 1a. That is, the air passes from the first opening 45 to the fourth opening 60 and is taken into the second dilution air flow path 42b, passes through the third opening 46, and passes through the first dilution air flow path 42a. It is discharged from the opening 48.

With such a configuration, even if combustion exhaust gas containing a high concentration of carbon dioxide is generated in the combustion unit 5 during operation of the fuel cell system 101, it is guided from the combustion exhaust gas flow path 43 to the exhaust port 49. The combustion exhaust gas and the air having a low carbon dioxide concentration guided from the diluting air flow path 42 to the second opening 48 can be merged and mixed at the diluted exhaust gas exhaust port 44 to dilute the carbon dioxide concentration and discharge. It will be possible.

Further, since the configuration is such that the air outside the housing 1 is sucked from the first opening 45, even when the fuel cell system 101 is installed in the pipe space chamber, the surrounding air can be sucked in to dilute the combustion exhaust gas. it can.

Further, by adopting a configuration in which the combustion exhaust gas and air are combined and discharged, the discharge flow velocity of the combustion exhaust gas discharged from the fuel cell system 101 can be increased, and the reach of the discharged combustion exhaust gas can be increased. It is possible to prevent staying in a common corridor. Therefore, it is possible to suppress deterioration of air quality in common corridors and the like.

Further, by adding a configuration in which the dilution air is sucked not only from the inside of the housing 1 but also from the outside of the housing 1, the flow rate of the ventilation air from the inside of the housing 1 can be suppressed, and the inside of the housing 1, especially The thermal balance around the reforming unit 4 and the fuel cell 3 can be maintained, and the operation of the fuel cell system 101 can be stabilized.

In the present embodiment, the first opening 45 for taking in the diluted air and the diluted exhaust gas exhaust port 44 for discharging the diluted combustion exhaust gas can be formed apart from each other. Therefore, it is possible to prevent the combustion exhaust gas from being taken in as dilution air from the first opening 45 as a shortcut.

Further, in the present embodiment, the second dilution air flow path 42b is provided inside the housing 1. The first opening 45, which is a suction port for the air for dilution, and the third opening 46, which leads out the air for dilution to the exhaust cover 40 side, are provided on one side wall 1a of the housing 1. Therefore, it is necessary to change the traveling direction of the air flow by 180 °. By providing a part of the dilution air flow path 42 inside the housing 1, the bending portion of the dilution air flow path 42 becomes steep, so that the flow path resistance increases and the air flow velocity slows down. Can be suppressed.

Further, in the diluted exhaust gas exhaust port 44, the second opening 48 and the exhaust port 49 are arranged in this order from the top.

FIG. 6A is a three-dimensional configuration diagram showing the configuration of the exhaust cover 40, and FIG. 6B is a three-dimensional sectional view showing the configuration of the first dilution air flow path 42a and the second dilution air flow path 42b. It was shown to.

With such a configuration, the second opening 48, which is an outlet for air whose temperature is lower than the temperature of the combustion exhaust gas, is arranged above the exhaust port 49, which is the outlet for the combustion exhaust gas. It is possible to suppress the upward winding of the combustion exhaust gas F ₁ along the low air flow F ₂ . Therefore, the diluted exhaust gas can be discharged farther toward the discharge direction of the diluted exhaust gas exhaust port 44.

Further, the fuel cell system 101 includes a fan 47 in the dilution air flow path 42. The fan 47 is installed so as to cover the third opening 46 from the inside of the one side wall 1a. As a result, the air outside the housing 1 can be taken into the dilution air flow path 42 through the first opening 45. The rotation speed of the fan 47 is controlled by the control unit 28.

In this way, by taking in the air outside the housing 1 as the dilution air into the dilution air flow path 42 by the fan 47, even if there is no wind in the vicinity where the fuel cell system 101 is installed, the dilution is performed. It is possible to secure the flow rate of air for use.

In addition, during non-steady operation such as start-up operation of the fuel cell 3, the combustion state of the combustion unit 5 may fluctuate due to load fluctuation, and the amount of exhaust gas may fluctuate. Fluctuations in the emission amount of the combustion exhaust gas can be detected from at least one information of the power generation amount of the fuel cell 3, the supply amount of the combustion air supplied by the combustion unit 5, and the supply amount of the raw material gas, and the emission amount can also be predicted. Therefore, the control unit 28 controls the rotation speed of the fan 47 based on at least one information of the power generation amount of the fuel cell 3, the supply amount of the combustion air supplied by the combustion unit 5, and the supply amount of the raw material gas. It may be configured.

With such a configuration, the rotation speed of the fan 47 is controlled according to the emission amount of the combustion exhaust gas, and the flow rate of the air for dilution is controlled to appropriately control the carbon dioxide concentration in the diluted exhaust gas. Can be done. In addition, exhaust gas management can be automated by predicting the amount of combustion exhaust gas emitted based on the amount of power generated by the fuel cell, the amount of combustion air supplied by the combustion unit, or the amount of combustion gas supplied. ..

Further, an exhaust pipe 50 extending from the inner peripheral portion of the diluted exhaust gas exhaust port 44 may be provided. The partition member 41 may extend to the inside of the exhaust stack 50. With such a configuration, the decrease in the speed at which the diluting air and the combustion exhaust gas pass through the exhaust stack 50 is suppressed, and the diluted exhaust gas is discharged farther toward the discharge direction of the diluted exhaust gas exhaust port 44. be able to.

Further, with such a configuration, when the fuel cell system 101 is installed in the pipe space room or the like, the exhaust gas is diluted by ejecting the exhaust pipe from the opening formed in the door of the pipe space room or the like. Can be discharged toward the outside of the installation space.

Further, even after the combustion exhaust gas is discharged to the combustion exhaust gas flow path 43 provided inside the exhaust cover 40, the condensation of water vapor in the combustion exhaust gas continues to occur. In the present embodiment, the combustion exhaust gas flow path 43 is provided below, and a part thereof communicates with the diffusion duct portion 32 protruding to the outside of the housing 1. Further, as shown in FIG. 1, by configuring the bottom of the exhaust cover 40 to be inclined toward the diffusion duct portion 32, the condensed water collected in the combustion exhaust gas flow path 43 is collected in the diffusion duct portion 32 and drained. It can be discharged to the outside of the housing 1 from the unit 33 via a drainage member (not shown). Here, the condensed water due to the condensation of water vapor in the exhaust gas is acidic, and the exhaust cover 40 is liable to be corroded. With such a configuration, it is possible to prevent the exhaust cover 40 from being exposed to condensed water and to prevent corrosion of the exhaust cover 40.

Although the first opening 45 is formed on the side surface of the exhaust cover 40 in the present embodiment, it may be formed on the surface of the exhaust cover 40 where the diluted exhaust gas exhaust port 44 and the exhaust pipe 50 are provided.
(Structure that discharges the air inside the housing to the dilution air flow path)
Generally, in a fuel cell system, the temperature inside the housing is detected and the operation permission of the fuel cell system is restricted by the control unit to ensure the stability of fuel cell power generation, and the water temperature and accessories in a high temperature environment. The temperature rise of the fuel cell is suppressed.
In the present embodiment, the air inside the housing 1 is discharged to the outside through the communication hole 91 formed in the dilution air flow path 42 (42b).

As shown in FIGS. 4 and 6B, a communication hole 91 is formed on one wall surface of the dilution air flow path 42b. The air inside the housing 1 is discharged to the outside of the housing 1 from the second dilution air flow path 42b through the communication hole 91. With such a configuration, ventilation inside the housing 1 is promoted.

Further, the flow rate adjusting means can be provided in the communication hole 91. In the following description, as an example, a case where the valve assembly 93 shown in FIG. 10 is used as the flow rate adjusting means will be described.

FIG. 10 shows the configuration of the valve assembly 93, which is an example of the opening / closing means. The valve assembly 93 is provided on the side wall of the second dilution air flow path 42b, and has a function of adjusting the flow rate of the air flowing out from the inside of the housing 1 to the second dilution air flow path 42.

The valve assembly 93 is mainly composed of a housing 94 and a butterfly valve 95. A communication hole 91 is formed in the housing 94, and the butterfly valve 95 is rotatable with the valve shaft 97 inserted in the shaft hole 96. The opening degree of the communication hole 91 can be adjusted by controlling the rotation of the valve shaft 97 via an opening / closing degree adjusting unit (not shown) and changing the posture of the butterfly valve 95.

When the valve assembly 93 is installed in the communication hole 91, for example, the control unit 28 controls an open / close degree adjusting unit (not shown), and the valve assembly 93 is discharged from the inside of the housing 1 to the second dilution air flow path through the communication hole 91. The air flow rate can be adjusted. Therefore, the design likelihood of the communication hole 91 can be increased.

Further, the adjustment of the air flow rate by the valve assembly 93 is also effective for adjusting the internal temperature of the housing 1. The temperature detection unit 97 in FIG. 4 can directly or indirectly detect the internal temperature of the housing 1. For example, when the detection temperature of the temperature detection unit 97 exceeds a predetermined temperature, the opening degree of the valve assembly 93 is increased to increase the air flow rate discharged from the inside of the housing 1 to the second dilution air flow path 42b. As a result, the effect of promoting ventilation inside the housing 1 and lowering the temperature inside the housing 1 can be obtained.

The flow rate of the air discharged from the inside of the housing 1 can also be adjusted by arbitrarily controlling the opening degree of the valve assembly 93, the rotation speeds of the ventilation fan 52, the fan 47, and the intake fan 24a. ..

As a result, when the internal temperature of the housing 1 exceeds a predetermined temperature, the fuel cell system 101 promotes ventilation inside the housing 1, so that a malfunction of the fuel cell system 101 can be avoided.

In the present embodiment, the temperature detection unit 97 is arranged near the bottom of the housing 1, but the present invention is not limited to this. It may be arranged in the vicinity of a portion to be monitored, for example, the combustion unit 5 or the fuel cell 3.

Further, when the ventilation fan 52 fails and the inside of the housing 1 is not sufficiently ventilated, the fuel cell system 101 is provided with a communication hole 91 provided in the dilution air flow path 42 instead of the ventilation fan 52. Since the air inside the body 1 can be discharged, it is possible to avoid a malfunction of the fuel cell system 101.
(Embodiment 3)
The fuel cell system 102 according to the third embodiment has the same basic configuration as the fuel cell system 100 according to the first embodiment, but has a first opening 45, which is a suction port for dilution air, as one side wall of the housing 1. The difference is that it is formed at a position covered by the exhaust cover 40 of 1a and is configured to take in diluted air from a part of the exhaust stack 50. Therefore, the same parts as those operated by the fuel cell system 100 according to the embodiment are designated by the same reference numerals, duplicate description is omitted, and a configuration in which combustion exhaust gas is diluted and exhausted will be described.
(Combustion exhaust gas is diluted and exhausted)
A method of discharging the combustion exhaust gas discharged from the combustion unit 5 will be described with reference to FIGS. 7, 8 and 9.

The combustion exhaust gas discharged from the combustion unit 5 is guided to the diffusion duct unit 32 through the exhaust duct 29. The diffusion duct portion 32 is connected to a housing exhaust port 31 formed on one side wall 1a of the housing 1. The diffusion duct portion 32 is attached to one side wall 1a from the inside of the housing 1, and integrally covers the housing exhaust port 31. The diffusion duct portion 32 leads out the combustion exhaust gas toward the housing exhaust port 31. The diffusion duct portion 32 has a larger cross-sectional area of the flow path of the combustion exhaust gas than the exhaust duct 29. As a result, the combustion exhaust gas derived from the exhaust duct 29 diffuses in the diffusion duct portion 32, the flow velocity decreases, and the water vapor contained in the combustion exhaust gas is promoted to condense.

The condensed water generated by condensing the water vapor contained in the combustion exhaust gas in the diffusion duct portion 32 is discharged from the drainage portion 33 to the outside of the housing 1 via a drainage member (not shown). The water vapor in the exhaust gas condenses into condensed water, which accumulates at the bottom of the diffusion duct portion 32. Here, the condensed water due to the condensation of water vapor in the exhaust gas is acidic, and the diffusion duct portion 32 is likely to be corroded. On the other hand, by providing the diffusion duct portion 32 with a drainage portion 33 for discharging condensed water, it is possible to suppress exposure of the diffusion duct portion 32 to the condensed water and prevent corrosion of the diffusion duct portion 32. ..

As shown in FIG. 7, a part of the diffusion duct portion 32 may be configured to protrude to the outside of the housing 1. With such a configuration, the combustion exhaust gas led out to the diffusion duct portion 32 is further cooled, and it is possible to promote the condensation of the water vapor contained in the combustion exhaust gas.

Next, the configuration of the exhaust gas diluting unit 90 will be described. The exhaust cover 40 is provided with an exhaust pipe 50. Inside the exhaust stack 50, a first partition member 61 and a second partition member 62 form a first dilution air flow path 42a and a casing for taking in dilution air from the outside of the housing 1 in order from the top in the vertical direction. It is partitioned into a dilution air intake flow path 42c and a combustion exhaust gas flow path 43 that discharge the dilution air toward the outside of the body 1. On the open end side of the exhaust stack 50, the first partition member 61 and the second partition member 62 form an air intake port 63 for taking in dilution air from the outside of the housing 1 in order from the top in the vertical direction, and a housing. It is divided into an air discharge port 64 that discharges dilution air toward the outside of 1 and a combustion exhaust gas discharge port 65 that discharges combustion exhaust gas.

Similar to other embodiments, an exhaust cover 40 is attached to one side wall 1a of the housing 1 so as to cover the housing exhaust port 31 from the outside. The combustion exhaust gas discharged from the housing exhaust port 31 is discharged to the outside of the housing 1 from the combustion exhaust gas discharge port 65 via the combustion exhaust gas flow path 43. The role of the combustion exhaust gas flow path 43 is to guide the combustion exhaust gas discharged from the housing exhaust port 31 to the exhaust port 49 via the diffusion duct portion 32.

A first opening 45 and a third opening 46 are formed on one side wall 1a of the housing 1. The first opening 45 and the third opening 46 are covered with an exhaust cover 40 from the outside of one side wall 1a of the housing 1, the first opening 45 communicates with the dilution air intake flow path 42c, and the third opening 46 is the first. It communicates with the air flow path 42a for dilution. Further, the first opening 45 and the third opening 46 are covered from the inside of the housing 1 by the second dilution air flow path 42b.

As described above, in the present embodiment, the dilution air flow path 42 is provided inside the exhaust cover 40, the dilution air intake flow path 42c, the first dilution air flow path 42a, and the inside of the housing 1. It is composed of the provided second dilution air flow path 42b. As shown in FIG. 7, the air taken in from the air intake port 63 is introduced into the second dilution air flow path 42b from the first opening 45 via the dilution air intake flow path 42c, and is introduced into the third opening 46. Is discharged to the outside of the housing 1 from the air discharge port 64 via the first dilution air flow path 42a.

A three-dimensional configuration diagram showing the configuration of the exhaust cover 40 is shown in FIG. 9A, showing the configurations of the first dilution air flow path 42a, the second dilution air flow path 42b, and the dilution air suction flow path 42c. A sectional view is shown in FIG. 9 (B).

With such a configuration, even if combustion exhaust gas containing a high concentration of carbon dioxide is generated in the combustion unit 5 during operation of the fuel cell system 102, the combustion exhaust gas flow path 43 is connected to the combustion exhaust gas discharge port 65. Combustion exhaust gas guided and carbon dioxide guided from the dilution air flow path (first dilution air flow path 42a, second dilution air flow path 42b, dilution air intake flow path 42c) to the air discharge port 64. It is possible to combine and mix low-concentration air at the open end of the exhaust stack 50 to dilute the carbon dioxide concentration and discharge it.

In the present embodiment, since the air outside the housing 1 is sucked from the air intake port 63, even when the fuel cell system 102 is installed in the pipe space chamber, the surrounding air is sucked in and the combustion exhaust gas is discharged. Can be diluted.

Further, by adopting a configuration in which the combustion exhaust gas and the air are merged and discharged, the discharge flow rate of the combustion exhaust gas discharged from the fuel cell system 102 can be increased, and the reach of the discharged combustion exhaust gas can be increased. It is possible to prevent staying in a common corridor. Therefore, it is possible to suppress deterioration of air quality in common corridors and the like.

Further, by adding a configuration in which the dilution air is sucked not only from the inside of the housing 1 but also from the outside of the housing 1, the flow rate of the ventilation air from the inside of the housing 1 can be suppressed, and the inside of the housing 1, especially The thermal balance around the reforming unit 4 and the fuel cell 3 can be maintained, and the operation of the fuel cell system 102 can be stabilized.

In the present embodiment, the air intake port 63, the air discharge port 64, and the combustion exhaust gas discharge port 65 are opened inside the exhaust stack. With this configuration, the dilution air flow path that sucks in external air from the air intake port 63 and discharges the air to the outside from the air discharge port 64 that opens toward the open end of the exhaust stack 50 is compactly designed. can do.

Further, at the open end of the exhaust pipe 50, the air intake port 63, the air discharge port 64, and the combustion exhaust gas discharge port 65 are arranged in this order from above. By arranging the air discharge port 64 that discharges the air for dilution between the combustion exhaust gas discharge port 65 that discharges the combustion exhaust gas and the air intake port 63 that sucks in air, the combustion exhaust gas discharged from the combustion exhaust gas discharge port 65 Can be prevented from being shortcut to the air intake port 63. As a result, the combustion exhaust gas can be efficiently diluted.

Further, in the present embodiment, the second dilution air flow path 42b is provided inside the housing 1. The first opening 45, which is a suction port for the air for dilution, and the third opening 46, which leads out the air for dilution to the exhaust cover 40 side, are provided on one side wall 1a of the housing 1. Therefore, it is necessary to change the traveling direction of the air flow by 180 °. By providing a part of the dilution air flow path inside the housing 1, the bending portion of the dilution air flow path becomes steep, so that the flow path resistance increases and the air flow velocity slows down. Can be suppressed.

Further, the fuel cell system 102 includes a fan 47 in the dilution air flow path 42. The fan 47 is installed so as to cover the third opening 46 from the inside of the one side wall 1a. As a result, the air outside the housing 1 can be taken into the dilution air flow path 42 through the first opening 45. The rotation speed of the fan 47 is controlled by the control unit 28.

In this way, by taking the air outside the housing 1 into the dilution air flow path 42 as the dilution air by the fan 47, even if there is no wind in the vicinity where the fuel cell system 102 is installed, the dilution is performed. It is possible to secure the flow rate of air for use.

In addition, during non-steady operation such as start-up operation of the fuel cell 3, the combustion state of the combustion unit 5 may fluctuate due to load fluctuation, and the amount of exhaust gas may fluctuate. Fluctuations in the emission amount of the combustion exhaust gas can be detected from at least one information of the power generation amount of the fuel cell 3, the supply amount of the combustion air supplied by the combustion unit 5, and the supply amount of the raw material gas, and the emission amount can also be predicted. Therefore, the control unit 28 controls the rotation speed of the fan 47 based on at least one information of the power generation amount of the fuel cell 3, the supply amount of the combustion air supplied by the combustion unit 5, and the supply amount of the raw material gas. It may be configured.

With such a configuration, the rotation speed of the fan 47 is controlled according to the emission amount of the combustion exhaust gas, and the flow rate of the air for dilution is controlled to appropriately control the carbon dioxide concentration in the diluted exhaust gas. Can be done. In addition, exhaust gas management can be automated by predicting the amount of combustion exhaust gas emitted based on the amount of power generated by the fuel cell, the amount of combustion air supplied by the combustion unit, or the amount of combustion gas supplied. ..

Further, even after the combustion exhaust gas is discharged to the combustion exhaust gas flow path 43 provided inside the exhaust cover 40, the condensation of water vapor in the combustion exhaust gas continues to occur. In the present embodiment, the combustion exhaust gas flow path 43 is provided below, and a part thereof communicates with the diffusion duct portion 32 protruding to the outside of the housing 1. Further, as shown in FIG. 1, by configuring the bottom of the exhaust cover 40 to be inclined toward the diffusion duct portion 32, the condensed water collected in the combustion exhaust gas flow path 43 is collected in the diffusion duct portion 32 and drained. It can be discharged to the outside of the housing 1 from the unit 33 via a drainage member (not shown). Here, the condensed water due to the condensation of water vapor in the exhaust gas is acidic, and the exhaust cover 40 is liable to be corroded. With such a configuration, it is possible to prevent the exhaust cover 40 from being exposed to condensed water and to prevent corrosion of the exhaust cover 40.

Further, since the exhaust pipe 50 is provided, when the fuel cell system 102 is installed in the pipe space chamber or the like, the exhaust pipe is ejected from the opening formed in the door of the pipe space chamber or the like to dilute the combustion exhaust gas. Can be discharged toward the outside of the installation space.

In the present embodiment, the exhaust pipe 50 is formed on the exhaust cover 40, but the present invention is not limited to this. When the exhaust cover 40 is not provided, the air intake port 63, the air discharge port 64, and the combustion exhaust gas discharge port 65 are arranged in this order on the front member of the exhaust cover 40 from above in the vertical direction. Even in this case, by arranging the air discharge port 64 for discharging the air for dilution between the combustion exhaust gas discharge port 65 for discharging the combustion exhaust gas and the air intake port 63 for sucking the air, the air is discharged from the combustion exhaust gas discharge port 65. It is possible to prevent the produced combustion exhaust gas from being shortcut to the air intake port 63. As a result, the combustion exhaust gas can be efficiently diluted.
(Structure that discharges the air inside the housing to the dilution air flow path)
Generally, in a fuel cell system, the temperature inside the housing is detected and the control unit limits the operation permission of the fuel cell system to ensure the stability of fuel cell power generation, and the water temperature and accessories in a high temperature environment. The temperature rise of the fuel cell is suppressed.
In the present embodiment, the air inside the housing 1 is discharged to the outside through the communication hole 91 formed in the dilution air flow path 42 (42b).

As shown in FIGS. 7 and 9B, a communication hole 91 is formed on one wall surface of the dilution air flow path 42b. The air inside the housing 1 is discharged to the outside of the housing 1 from the second dilution air flow path 42b through the communication hole 91. With such a configuration, ventilation inside the housing 1 is promoted.

Further, the flow rate adjusting means can be provided in the communication hole 91. In the following description, as an example, a case where the valve assembly 93 shown in FIG. 10 is used as the flow rate adjusting means will be described.

FIG. 10 shows the configuration of the valve assembly 93, which is an example of the opening / closing means. The valve assembly 93 is provided on the side wall of the second dilution air flow path 42b, and has a function of adjusting the flow rate of the air flowing out from the inside of the housing 1 to the second dilution air flow path 42.

The valve assembly 93 is mainly composed of a housing 94 and a butterfly valve 95. A communication hole 91 is formed in the housing 94, and the butterfly valve 95 is rotatable with the valve shaft 97 inserted in the shaft hole 96. The opening degree of the communication hole 91 can be adjusted by controlling the rotation of the valve shaft 97 via an opening / closing degree adjusting unit (not shown) and changing the posture of the butterfly valve 95.

When the valve assembly 93 is installed in the communication hole 91, for example, the control unit 28 controls an open / close degree adjusting unit (not shown), and the valve assembly 93 is discharged from the inside of the housing 1 to the second dilution air flow path through the communication hole 91. The air flow rate can be adjusted. Therefore, the design likelihood of the communication hole 91 can be increased.

Further, the adjustment of the air flow rate by the valve assembly 93 is also effective for adjusting the internal temperature of the housing 1. The temperature detection unit 97 in FIG. 7 can directly or indirectly detect the internal temperature of the housing 1. For example, when the detection temperature of the temperature detection unit 97 exceeds a predetermined temperature, the opening degree of the valve assembly 93 is increased to increase the air flow rate discharged from the inside of the housing 1 to the second dilution air flow path 42b. As a result, the effect of promoting ventilation inside the housing 1 and lowering the temperature inside the housing 1 can be obtained.

The flow rate of the air discharged from the inside of the housing 1 can also be adjusted by arbitrarily controlling the opening degree of the valve assembly 93, the rotation speeds of the ventilation fan 52, the fan 47, and the intake fan 24a. ..

As a result, when the internal temperature of the housing 1 exceeds a predetermined temperature, the fuel cell system 102 promotes ventilation inside the housing 1, so that a malfunction of the fuel cell system 102 can be avoided.

In the present embodiment, the temperature detection unit 97 is arranged near the bottom of the housing 1, but the present invention is not limited to this. It may be arranged in the vicinity of a portion to be monitored, for example, the combustion unit 5 or the fuel cell 3.

Further, when the ventilation fan 52 fails and the inside of the housing 1 is not sufficiently ventilated, the fuel cell system 102 can be mounted through a communication hole 91 provided in the dilution air flow path 42 instead of the ventilation fan 52. Since the air inside the body 1 can be discharged, it is possible to avoid a malfunction of the fuel cell system 102.

From the above description, many improvements and other embodiments of the present invention will be apparent to those skilled in the art. Therefore, the above description should be construed as an example only and is provided for the purpose of teaching those skilled in the art the best mode of carrying out the present invention. The details of its structure and / or function can be substantially changed without departing from the spirit of the present invention.

The fuel cell system of the present invention can improve the environmental friendliness of the fuel cell system, and is particularly useful for applications such as a fuel cell system installed in an apartment house.

1 Housing 1a One side wall 2 Legs 3 Fuel cell 4 Reformer 5 Combustion part 6 Tank 10 1st water circuit 11 Raw material gas supply path 12 2nd water circuit 13 Heat exchanger 14 Heat recovery water channels 14a, 14b Heat recovery piping 15 Tank 20 Hydrogen-containing gas supply path 21 Circuit housing 22 Electronic circuit board 22a Controller 22b Inverter 23, 24 Intake port 24a Intake fan 25 Ventilation duct 26 Hood 27 Exhaust port 28 Control unit 31 Housing exhaust port 32 Diffusion duct part 33 Drainage Part 40 Exhaust cover 41 Partition member 42 Diluting air flow path 42a First dilution air flow path 42b Second dilution air flow path 42c Diluting air intake flow path 43 Combustion exhaust gas flow path 45 First opening 44 Diluted exhaust gas exhaust port 46 Third opening 47 Fan 48 Second opening 49 Exhaust port 50 Exhaust pipe 51 Hood 52 Ventilation fan 53 Ventilation port 60 Fourth opening 61 First partition member 62 Second partition member 63 Air intake port 64 Air exhaust port 65 Exhaust gas from combustion Outlet 90 Exhaust gas diluting part 91 Communication hole 93 Valve assembly 94 Housing 95 Butterfly valve 96 Shaft hole 96 Valve shaft 97 Temperature detection part 100, 101, 102 Fuel cell system

Claims (9)

A reforming unit that generates hydrogen-containing gas by the reforming reaction of the raw material gas,
A fuel cell that generates electricity using the hydrogen-containing gas and the oxidant gas,
A combustion unit that heats the reformed unit by burning a combustion gas composed of at least one of the raw material gas and the hydrogen-containing gas.
An exhaust duct for exhausting the combustion exhaust gas from the combustion part and
A housing that houses the reforming unit, the fuel cell, the combustion unit, and the exhaust duct.
A housing exhaust port provided on one side wall of the housing and exhausting the combustion exhaust gas to the outside from the exhaust duct,
It is provided with an exhaust gas diluting unit that dilutes the combustion exhaust gas derived from the housing exhaust port with air taken in from the outside and discharges it to the outside.
The exhaust gas diluting part
An exhaust cover installed so as to cover the housing exhaust port from the outside of the housing,
Diluted exhaust gas exhaust port provided on the exhaust cover and
A dilution air flow path that sucks in external air from a first opening opened in one side wall of the housing and discharges the air to the outside through a second opening of the diluted exhaust gas exhaust port.
A communication hole for discharging the air in the housing from the dilution air flow path to the dilution air flow path, and
It is partitioned from the diluting air flow path, and includes a combustion exhaust gas flow path that discharges the combustion exhaust gas to the outside from the exhaust port of the diluted exhaust gas exhaust port via the space sandwiched between the exhaust cover and the one side wall. Also, fuel cell system. The fuel cell system according to claim 1, further comprising a flow rate adjusting means provided in the communication hole and capable of adjusting the flow rate of discharging air in the housing from the communication hole to the dilution air flow path. The fuel cell system according to claim 1 or 2, wherein the diluted exhaust gas exhaust port is arranged in the order of the second opening and the exhaust port from above. The first opening is provided inside the exhaust gas diluting portion and is open toward the diluted exhaust gas exhaust port. At the diluted exhaust gas exhaust port, the first opening, the second opening, and the exhaust are from above. The fuel cell system according to any one of claims 1 to 3, which is arranged in the order of the mouth. The fuel cell system according to any one of claims 1 to 5, wherein an exhaust stack extending from the inner peripheral portion of the diluted exhaust gas exhaust port is provided. The fuel cell system according to any one of claims 1 to 5, wherein a fan is provided in the dilution air flow path. The sixth aspect of claim 6, wherein the rotation speed of the fan is controlled according to at least one information of the power generation amount of the fuel cell, the supply amount of combustion air supplied by the combustion unit, and the supply amount of the raw material gas. Fuel cell system. The fuel cell system according to any one of claims 1 to 7, wherein a part of the dilution air flow path is provided inside the housing. Any one of claims 1 to 8 provided with a drain hole formed in the combustion exhaust gas flow path and discharged from the exhaust cover to discharge condensed water generated from the combustion exhaust gas led out into the combustion exhaust gas flow path. The fuel cell system described in paragraph 1.

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