JP2003317780A - Fuel cell module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To effectively utilize the heat generated in a fuel battery cell as the heat for heating air in a fuel cell module and an air preheater while suppressing the temperature of the wall surfaces of tube plates in feed chambers in the fuel cell module. <P>SOLUTION: This fuel cell module comprises a reformer 22 and a fuel cell module body 21. The reformer 22 reforms fuel gas 51. The fuel cell module body 21 generates power by using the reformed fuel gas 51 and oxidizer gas 52. The reformer 22 reforms by utilizing an oxidizer heat as the heat of the oxidizer gas 52 forced out from the fuel cell module body 21. The reformer 22 comprises a first reforming part 22-1 and a second reforming part 22-2. The first reforming part 22-1 reforms by utilizing the heat of the fuel gas 51 reformed by the second reforming part 22-2. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fuel cell module, and more particularly to a fuel cell module in which heat is effectively used.

[0002]

2. Description of the Related Art FIG. 11 shows an example of a schematic structure of a conventional cylindrical solid oxide fuel cell module 100. In FIG. 11, the part relating to the collection of the generated power is omitted.

Referring to FIG. 11, the fuel cell module 1
00 is the fuel gas supply unit 110 and the oxidant gas supply chamber 1
07 and a fuel cell cell tube 103 which is a power generation unit. The fuel gas supply unit 110 includes a supply chamber 108 and an exhaust chamber 1.
09 and. Further, the fuel cell tube 103 has an outer tube 104 and an inner tube 105. The oxidant gas supply chamber 107 includes the heat insulator 120, the side plate 121, and the bottom plate 1.
22.

Top plate 112, side plate 113 and tube plate 114
The supply chamber 108 configured by supplies the fuel gas 101 to the fuel cell tube 103. Also, the tube sheet 114 and the side sheet 1
The discharge chamber 109 constituted by 16 and the tube plate 117 discharges the unused fuel gas 101 in the fuel cell tube 103.

The oxidant gas supply chamber 107 composed of the tube plate 117, the side plate 121, and the bottom plate 122 includes a heat insulator 120 that thermally protects the tube plate 117 and a fuel cell tube 103. The oxidant gas 102 is supplied to the pipe 103.

One end of the outer tube 104 of the fuel cell tube 103 is opened and connected to the tube sheet 117, and the other end extends to the oxidant gas supply chamber 107 and is closed. Outer tube 104
Are fixed to and supported by the tube sheet 117 by a fixing jig. One end of the inner pipe 105 is opened and connected to the tube plate 114, and the other end thereof is extended to the vicinity of the other end of the outer pipe 105 and opened. The inner tube 105 is fixed to the tube sheet 11 by a fixing jig.
4 is fixed and supported.

In the tube sheet 117 of the discharge chamber 109, the side of the fuel cell tube 103 where the fuel cell is located is thermally protected by a heat insulator 120. On the other hand, the inside of the discharge chamber 109 of the tube sheet 117 and the tube sheet 114 are not thermally protected. Therefore, when the temperatures of the supplied fuel gas 101 and the used fuel gas 101 are high, the materials of the tube sheet 114 and the tube sheet 117 need to be heat resistant materials. However, if there is a method capable of sufficiently increasing the temperature of the fuel gas 101 immediately before the power generation region of the fuel cell tube 103 (inside the oxidant gas supply chamber 107), it is necessary to raise the temperature of the fuel gas 101 in the supply chamber 108 so much. Disappears.
In addition to that, spent fuel gas 10 immediately after the power generation region
If there is a method capable of sufficiently lowering the temperature of 1, the discharge chamber 10
The temperature of the spent fuel gas 101 in 9 becomes low. That is, it is not necessary to use materials having high heat resistance as the materials of the tube sheet 114 and the tube sheet 117, and the cost can be reduced.

As such a method, there is effective heat exchange between the inner tube 105 and the outer tube 104 near the heat insulator 120 of the fuel cell tube 103 of the tube sheet 114. Due to the heat exchange, the fuel gas 1 in the supply chamber 108 and the discharge chamber 109
01 can be low temperature.

Here, the fuel gas 101 is obtained by reforming a hydrocarbon gas. The (equilibrium) composition of the reformed fuel gas 101 is determined by the reforming temperature. In order to increase the amount of hydrogen and carbon monoxide used for power generation in the fuel cell, it is desirable to raise the reforming temperature.

On the other hand, if a large amount of energy is input to obtain a high reforming temperature, energy loss may increase and energy efficiency may decrease. Therefore, the reforming temperature is determined by the energy input to the reforming and the composition of the reformed fuel gas.

However, the temperature is usually high, and in order to directly supply the reformed fuel gas to the supply chamber 108, it is necessary to use a material having high heat resistance for the tube sheet 114 or the like.

The fuel gas 101 reformed at high temperature is
A technique that enables supply to the supply chamber 108 manufactured without using a material having high heat resistance is desired. There is a demand for a technique for reducing the temperature of the reformed high-temperature fuel gas 101 without wasting its thermal energy. Supply room 1
There is a demand for a technique capable of lowering the temperature of the 08 tube plate 114 and the like.

In a solid oxide fuel cell, 900
Since it is operated at a temperature of from 1000 to 1000 ° C, it is conceivable that the exhaust heat (heat of the spent fuel gas and oxidant gas) is effectively used by a method such as heat exchange. However, the heat is more likely to be dissipated to the outside as the distance from the fuel cell increases.

Further, in the case of a combined power generation system combined with a gas turbine, an exhaust heat recovery boiler, etc., the less wiring and piping to be connected to the fuel cell module from the outside, the easier the overall design and the easier the construction. To be For example, the number of heat exchange pipes should be as small as possible.

There is a demand for a technique for effectively utilizing the heat generated in the fuel cell in the fuel cell module. The heat generated in the fuel cell can be transferred to the fuel cell module without adding equipment such as piping for heat exchange with the outside.
There is a demand for effective technology.

[0016]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a fuel cell module capable of lowering the temperature of the wall surface of the tube sheet or the like of the supply chamber.

Another object of the present invention is a fuel cell module capable of supplying a fuel gas reformed at a high temperature to a supply chamber manufactured without using a material having high heat resistance. Is to provide.

Still another object of the present invention is to provide a fuel cell module capable of lowering the temperature of the reformed high temperature fuel gas while effectively utilizing its thermal energy.

Another object of the present invention is to provide a fuel cell module capable of effectively utilizing the heat generated in the fuel cell in the fuel cell module.

Another object of the present invention is to provide a fuel cell module capable of reforming a fuel gas by effectively utilizing the thermal energy of the reformed high temperature fuel gas.

[0021]

[Means for Solving the Problems] Means for solving the problems will be described below by using the numbers and symbols used in the embodiments of the present invention. These numbers / codes are added in parentheses in order to clarify the correspondence between the description in the claims and the embodiments of the invention. However, those numbers and signs should not be used for the interpretation of the technical scope of the invention described in [Claims].

Therefore, in order to solve the above problems, the fuel cell module of the present invention comprises a reformer (22) and a fuel cell module main body (21). Reformer (2
2) reforms the fuel gas (51). The fuel cell module body (21) has the reformed fuel gas (5
Power generation is performed using 1) and the oxidant gas (52). The reformer (22) is connected to the fuel cell module body (2
The reforming is performed by utilizing the heat of the oxidizing gas as the heat of the oxidizing gas (52) sent from 1).

Further, in the fuel cell module of the present invention, the reformer (22) comprises a first reforming section (22-1) and a second reforming section (22-2). First reforming section (22-1)
Perform a first reforming of the fuel gas (51) at a first temperature.
The second reforming section (22-2) is connected to the latter stage of the first reforming section (22-1), and the first reformed fuel gas (5
The second reforming of 1) is performed at a second temperature higher than the first temperature. Then, the second reforming section (22-2) uses the heat of the oxidizing agent to perform the second reforming. First reforming section (22-
In 1), the first reforming is performed using the fuel heat as the heat of the second reformed fuel gas (51).

Further, in the fuel cell module of the present invention, the oxidant gas (52) discharged from the reformer (22) and the oxidant gas (52) before being supplied to the fuel cell module main body (21) are used. (23) further comprising an air preheater for exchanging heat.

Further, the fuel cell module of the present invention performs heat exchange between the reformed fuel gas (51) and the oxidant gas (52) before being supplied to the fuel cell module main body (21). A fuel cooler (55) is further provided.

In order to solve the above problems, the reformer of the present invention is provided with a first pipe (12-3) and a first reforming section (22-1).
a), the second pipe (27-1), and the second reforming section (22-
2) and the third pipe (22-1b, 27-2). The first pipe (12-3) supplies the first fuel gas (51). The first reforming section (22-1a) includes the first pipe (1
2-3), and reforms the first fuel gas (51) to the second fuel gas (51). The second pipe (27-1) delivers the second fuel gas (51) from the first reforming section (22-1a). The second reforming section (22-2) is connected to the second pipe (27-
1) and reforms the second fuel gas (51) to the third fuel gas (51). Third pipe (22-1b, 27-
2) includes a first reforming section (22-1a), and delivers a third fuel gas (51) from the second reforming section (22-2). Then, the first reforming section (22-1a) is connected to the third fuel gas (5
The heat of 1) is used to perform the reforming of the first fuel gas (51).

Further, the reformer of the present invention comprises a second reforming section (2
2-2) is the inner pipe (22-2a) and the inner pipe (22-2a)
And a reforming catalyst section (22-2b) installed between the outer surface of the inner tube (22-2a) and the inner surface of the outer tube. Then, the outer pipe has a first end as the one end that is the third pipe (22-1b, 27-).
2), and the second end as the other end is closed. The inner pipe (22-2a) has a third end as one end connected to the second pipe (27-1), and a fourth end as the other end extends to the front of the second end and is open. Has been done.

In order to solve the above problems, the fuel cell module of the present invention comprises a reformer (22) and a fourth pipe (25).
-1) and a fuel cell module body (21). The reformer (22) is described in the preceding 2 items. The fourth pipe (25-1) is the third pipe (22-1b, 27-2).
And supplies a third fuel gas (51). The fuel cell module body (21) has a fourth pipe (25-1).
And the fifth pipe (26-
1) and is used to generate electricity using the third fuel gas (51) and the oxidant gas (52). The reformer (22) is installed near the fuel cell module body (21).
The second reforming section (22-2) of the reformer (22) further includes a gas flow section (22-2c) provided so as to cover the outer tube thereof. Then, the fuel cell module body (2
The second fuel gas (51) is reformed into the third fuel gas (51) by using the heat of the oxidant gas (52) supplied from 1) to the gas flow section (22-2c).

The fuel cell module of the present invention further comprises a sixth pipe (26-3) and an air preheater (23). The sixth pipe (26-3) sends the oxidant gas (52) from the reformer (22). Air preheater (23)
Is installed near the fuel cell module body (21),
An oxidant gas (52) delivered from the reformer (22),
Heat exchange with the oxidant gas (52) before being supplied to the fuel cell module body (21) is performed.

Further, in the fuel cell module of the present invention, the fuel cell module body (21) has a plurality of fuel cell cell tubes (33), a first fuel chamber (38), and a second fuel chamber (3).
9) and an air chamber (37). Fuel cells (41) are formed on the surface of the plurality of fuel cell tubes (33). The first fuel chamber (38) has a fourth pipe (25-
1) is connected to supply the third fuel gas (51) into the plurality of fuel cell tubes (33). Second fuel chamber (39)
Of the third fuel gas (51) discharges the used fuel cell pipes (33). Air chamber (37)
Is connected to the fifth pipe (26-1), and the first fuel chamber (3
8) and the second fuel chamber (39), and includes a plurality of fuel battery cell tubes (33), and supplies an oxidant gas (52) to the fuel battery cells (41). Then, in the first fuel chamber (38), one end portion of the plurality of fuel cell tubes (33) serves as one side surface of the first fuel chamber (38) as a first tube sheet (34).
A plurality of first fitting portions (38-2) which are opened and fitted to each other
including. The other end of the plurality of fuel cell tubes (33) of the second fuel chamber (39) is opened and fitted to the second tube plate (35) as one side surface of the second fuel chamber (39). Multiple second
A fitting portion (39-2) is included.

Further, the fuel cell module of the present invention comprises a reformer (22), a fuel cooler (55), and a fuel cell module body (21). The reformer (22) is
It is connected to a pipe (12-3) for supplying the fuel gas (51) and reforms the fuel gas (51). Fuel cooler (55)
Is connected to a pipe (25-1) for delivering the reformed fuel gas (51) from the reformer (22) and a pipe (11-4) for supplying the oxidant gas (52). Heat exchange between the reformed fuel gas (51) and the oxidant gas (52) is performed. The fuel cell module body (21) includes a pipe (25-3) for delivering the heat-exchanged fuel gas (51) from the fuel cooler (55) and the heat-exchanged oxidant gas (5).
2) is connected to a pipe (26-4 (-1)) for sending out, and heat generation is performed using the heat-exchanged fuel gas (51) and the heat-exchanged oxidant gas (52). Reformer (2
2) and the fuel cooler (55) are installed near the fuel cell module body (21). The reformer (22) is
The heat of the oxidant gas (52) delivered from the fuel cell module body (21) is used to reform the fuel gas (51).

In order to solve the above problems, the combined power generation system of the present invention comprises a gas turbine (2), a fuel cell module (1) and a combustor (8). The gas turbine (2) has a generator and compresses the oxidant gas (52). The fuel cell module (1) is described in any one of the above items, in which power is generated by the compressed oxidant gas (52) and the fuel gas (51). The combustor (8) burns the fuel gas (51) and the oxidant gas (52) used in the fuel cell module (1).
Then, the gas turbine (2) compresses the combustion gas (53) generated by the combustor (8) to drive the generator.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a fuel cell module according to the present invention will be described below with reference to the accompanying drawings.

In the present embodiment, a cylindrical type fuel cell module will be described as an example, but the present invention can be applied to a fuel cell having another cylindrical structure. Note that the same or corresponding portions in the respective embodiments will be described with the same reference numerals.

(Embodiment 1) FIG. 1 is a configuration diagram showing a first embodiment of a combined power generation system to which a fuel cell module according to the present invention is applied. The combined power generation system includes a fuel cell module 1, a gas turbine 2, a three-way valve 3, an air compressor 4, a primary fuel preheater 5, a pump 6, a three-way valve 7, a combustor 8, a three-way valve 9 and a chimney 10. Then, they are controlled by a control unit (not shown), and the oxidant gas pipe 1
1-1 to 11-7, fuel gas pipes 12-1 to 12-9, and combustion gas pipes 13-1 to 13-3 are connected.

The gas turbine 2 has a turbine, a compressor and a generator. The gas turbine 2 is provided with a combustion gas 53 (not shown) supplied via a combustion gas pipe 13-1.
Causes the turbine to rotate. Then, the rotation causes the generator to operate. At the same time, the rotation drives the compressor to compress the oxidant gas 52 (air in this embodiment) supplied through the oxidant gas pipe 11-1. After that, the oxidant gas 52 is supplied to the oxidant gas pipe 11-.
It is discharged to 2.

The three-way valve 3 supplies the oxidant gas 52 supplied through the oxidant gas pipe 11-2 to the oxidant gas pipe 11
-3 (for fuel cell module) and oxidant gas pipe 11
-6 (for the combustor 8 and connected to the oxidant gas pipe 11-5). The gas turbine 2 is controlled by a control unit (not shown).
And is controlled based on the operating conditions of the fuel cell module 1.

The air compressor 4 includes an oxidant gas pipe 11-3.
The oxidant gas 52 supplied via the is further compressed to the operating pressure of the fuel cell module 1. Then, the oxidant gas 52 is discharged to the oxidant gas pipe 11-4.

The three-way valve 9 supplies the fuel gas 51 supplied through the fuel gas pipe 12-1 to the fuel gas pipe 12-2.
(For fuel cell module) and fuel gas pipe 12-8
(Combustor 8 connection to fuel gas pipe 12-7). The control unit (not shown) controls the gas turbine 2 and the fuel cell module 1 based on operating conditions.

The primary fuel preheater 5 includes a fuel gas pipe 12-
The fuel gas 51 (low temperature side) supplied via 2 and the used fuel gas 51 (high temperature side) supplied from the fuel cell module 1 via the fuel gas pipe 12-4 are heat-exchanged. The fuel gas 51 on the low temperature side is heated and sent to the fuel gas pipe 12-3. The high temperature side fuel gas 51 is cooled and sent to the fuel gas pipe 12-5.

The pump 6 is a pump for feeding the fuel gas 51 supplied through the fuel gas pipe 12-5 to the fuel gas pipe 12-6.

The three-way valve 7 supplies the fuel gas 51 supplied through the fuel gas pipe 12-6 to the fuel gas pipe 12-9.
(For fuel cell module, connected to fuel gas pipe 12-3) and fuel gas pipe 12-7 (for combustor 8). The control unit (not shown) controls the gas turbine 2 and the fuel cell module 1 based on operating conditions.

The fuel cell module 1 uses the oxidant gas 52 supplied through the oxidant gas pipe 11-4 and the fuel gas 51 supplied through the fuel gas pipe 12-3 to generate electric power. . The fuel gas 51 (including the generated water vapor) used in the fuel cell module 1 is delivered to the fuel gas pipe 12-4. The oxidant gas 52 used in the fuel cell module 1 is sent to the oxidant gas pipe 11-5.

The combustor 8 includes an oxidant gas 52 supplied through an oxidant gas pipe 11-5 and a fuel gas pipe 12-.
The fuel gas 51 supplied via 7 is combusted to generate a combustion gas 53. The combustion gas 53 is the combustion gas pipe 13
-1.

The chimney 10 includes a combustion gas 53 supplied from the gas turbine 2 through a combustion gas pipe 13-2 and a combustion gas pipe 13-3, an oxidant gas pipe 11-7 and a combustion gas pipe 13-3. It is mixed with the oxidant gas 52 supplied through and discharged to the outside.

Here, the fuel gas 51 is a mixed gas of hydrocarbon gas and steam up to the reformer of the fuel cell module 1. Hydrocarbon gases are methane, propane,
Examples are gasoline, kerosene, light oil, and methanol. After reforming in the reformer, the fuel gas 51 contains hydrogen and carbon monoxide as main components. The fuel gas 51 used in the fuel cell module 1 is the remaining fuel gas 51 in which the required amount of fuel gas 51 has been consumed in the fuel cell module 1.
The oxidant gas 52 is a gas containing oxygen. The oxidant gas 52 is exemplified by air.

The oxidant gas 52 used in the fuel cell module 1 is the remaining oxidant gas 52 after the required amount of the oxidant gas 52 is consumed in the fuel cell module 1.

Next, the fuel cell module 1 will be described.

FIG. 2 is a diagram (cross-sectional view) showing the configuration of the first embodiment of the fuel cell module according to the present invention.
The fuel cell module 1 includes a fuel cell module body 2
1, a reformer 22, an air preheater 23, and a three-way valve 24. And, they are the fuel gas pipes 25-1 to 25-
2, oxidant gas pipes 26-1 to 26-3 and reforming pipe 2
It is connected by 7-1 to 27-2.

The reformer 22 reforms the fuel gas 51 supplied through the fuel gas pipe 12-3 and sends it to the fuel gas pipe 25-1. The 1st reforming part 22-1, the 2nd reforming part 22-2, the reforming piping 27-1, and the reforming piping 27-2 are included.

The first reforming section 22-1 includes the fuel gas pipe 12
The fuel gas 51 supplied through the second reforming unit 2
Steam reforming is performed at a lower temperature than 2-2. The energy input to the first reforming unit 22-1 includes the second reforming unit 2
The internal energy of the fuel gas 51 reformed in 2-2 is used. The fuel gas 51 becomes a fuel gas 51 containing hydrogen and carbon monoxide as main components by steam reforming and is sent to the reforming pipe 27-1.

The second reforming section 22-2 includes a reforming pipe 27-1.
The fuel gas 51 supplied via the first reforming unit 22-
Steam reforming is carried out at a higher temperature than in No. 1. Second reformer 2
The internal energy of the oxidant gas 52 sent from the fuel cell module 1 through the oxidant gas pipe 26-2 is used as the energy input to 2-2. Here, (the temperature of the fuel gas 51 reformed in the first reforming section 22-1) <(the temperature of the oxidant gas 52 sent through the oxidant gas pipe 26-2), the fuel gas 51 The composition after steam reforming of the fuel gas 51 in the first reforming section 22-1 is
The ratio of hydrogen to carbon monoxide is higher than that. Then, the fuel gas 51 is delivered to the reforming pipe 27-2.

The air preheater 23 is the oxidant gas pipe 11-.
The oxidant gas 52 (low temperature side) supplied via No. 4 and the oxidant gas 52 (high temperature side) supplied from the reformer 22 via the oxidant gas pipe 26-3 are heat-exchanged. The oxidant gas 52 on the low temperature side is heated and the oxidant gas pipe 26-1
Sent to. The oxidant gas 52 on the high temperature side is cooled and sent to the oxidant gas pipe 11-5.

The fuel cell module main body 21 includes an oxidant gas 52 supplied through an oxidant gas pipe 26-1.
Fuel gas 51 supplied through the fuel gas pipe 25-1
Generate electricity using and. The fuel gas 51 (including generated steam) used in the fuel cell module main body 21 is
It is delivered to the fuel gas pipe 25-2. The oxidant gas 52 (including the generated water vapor) used in the fuel cell module main body 21 is delivered to the oxidant gas pipe 26-2.

The three-way valve 24 supplies the fuel gas 51 supplied through the fuel gas pipe 25-2 to the fuel gas pipe 25-3.
(For the fuel cell module 21, connected to the fuel gas pipe 12-3) and the fuel gas pipe 12-4 (primary fuel preheater 5
For). A control unit (not shown) controls the fuel cell module 1 based on operating conditions.

Next, the fuel cell module 1 will be further described.

FIG. 3 is a sectional view showing in more detail the configuration of the first embodiment of the fuel cell module according to the present invention shown in FIG. The fuel cell module 1 includes a fuel cell module body 21, a reformer 22, and an air preheater 23 (the three-way valve 24 is omitted). They are fuel gas pipes 25
-1 to 25-2, oxidant gas pipes 26-1 to 26-3, and reforming pipes 27-1 to 27-2 are connected.

The reformer 22 includes a first reforming section 22-1 and a second reforming section 22-2, and includes the fuel cell module main body 21.
Is installed adjacent to. The first reforming section 22-1 has a double pipe structure including a catalyst section 22-1a and a gas circulation section 22-1b in order from the inside. Further, the reforming pipe 27-1 and the reforming pipe 27-2 have a double pipe structure in which the reforming pipe 27-1 is inside. The second reforming section 22-2 has a double pipe structure including a gas flow section 22-2a and a catalyst section 22-2b in order from the inside,
Further, the triple pipe structure includes a gas flow portion 22-2c formed so as to surround the double pipe structure.

Inside the double pipe structure, one side is a catalyst portion 22-1a connected to the fuel gas pipe 12-3, a reforming pipe 27-1 is connected to the catalyst portion 22-1a, The gas circulation unit 22-2a connected to the reforming pipe 27-1 is continuously arranged. The tip of the gas flow section 22-2a is open inside the reformer 22. On the outside of the double pipe structure, one side is connected to a fuel gas pipe 25-1 including a part of the fuel gas pipe 12-3, and a gas flow portion 22-1b,
A reforming pipe 27-2 connected to the gas distribution unit 22-1b,
The catalyst portion 22-2b connected to the reforming pipe 27-2 is continuously arranged. The tip of the catalyst portion 22-2b is closed.

Further, the second reforming section 22-2 is, as a triple pipe, an oxidant gas pipe 26-2 and an oxidant gas pipe 26.
-3 is connected, and the gas distribution part 22-2 provided so as to surround the catalyst part 22-2b is provided.

The catalyst portion 22-1a is connected to the fuel gas pipe 12-
The fuel gas 51 supplied through the catalyst unit 22-1
Steam reforming is carried out by the catalyst in a. The thickness is larger than that of the fuel gas pipe 12-3. As the catalyst, a conventionally used steam reforming catalyst (eg nickel / alumina) can be used. The fuel gas 51 containing hydrogen and carbon monoxide as main components by steam reforming is passed through the reforming pipe 27-1 to the second reforming section 2
2-2. The gas flow section 22-1b outside the catalyst section 22-1a causes the (high-temperature) fuel gas 51 reformed by the second reforming section 22-2 to flow around the catalyst section 22-1a. At that time, the (high-temperature) fuel gas 51 flows into the catalyst portion 2
By exchanging heat with the 2-1a, a part of the internal energy is released (heat exchange) to the catalyst section 22-1a. The energy is used for reforming the first reforming section 22-1.

The gas flow section 22-2a is provided with the reforming pipe 27-.
The fuel gas 51 supplied via 1 is circulated and transported to the closed tip of the double pipe structure. The fuel gas 51 turns back there and flows into the catalyst portion 22-2b outside the double pipe structure.

The catalyst section 22-2b further steam-reforms the fuel gas 51 with a catalyst contained therein. The catalyst is a steam reforming catalyst that has been used conventionally (example: nickel / alumina)
Is available. The reforming temperature is higher than that of the first reforming section 22-1. Therefore, the steam reforming causes the catalyst portion 22
The fuel gas 51 has a higher ratio of hydrogen and carbon monoxide combined (high temperature) than the reforming at -1a. After that, the (high-temperature) fuel gas 51 is delivered to the gas flow section 22-1b of the first reforming section 22-2 via the reforming pipe 27-2.

Gas flow section 22 outside catalyst section 22-2b
-2c causes the oxidant gas 52 used in the fuel cell module main body 21 to flow around the catalyst portion 22-2b. The oxidant gas 52 has a very high temperature, and the catalyst portion 22
-2b, by exchanging heat with -2b, a part of the internal energy is released to the catalyst section 22-2b. The energy is used for reforming the second reforming section 22-2. Then, the oxidant gas 52 is sent to the oxidant gas pipe 26-3.

Fuel gas 5 reformed by the catalyst section 22-2b
1 reaches the gas flow section 22-1b of the first reforming section 22-2 via the reforming pipe 27-2. Therefore, a part of the internal energy contained inside is released to the catalyst portion 22-1b, and the temperature is lowered. Then, the fuel gas 51 whose temperature has dropped is
It is supplied to the fuel cell module main body 21 through the fuel gas pipe 25-1.

The reformer 22 uses the heat of heat exchange for reforming, but may have an auxiliary heating device such as a burner or an electric heater. This is useful when there is little heat for heat exchange at startup or when the fuel supply amount is suddenly increased.

Further, although the reformer 22 carries out reforming in two stages, it is also possible to carry out reforming in multiple stages.
Also in that case, it is possible to carry out by utilizing heat exchange as in the present embodiment. For example, in the case of 3 levels, the first description
This can be implemented by dividing the reforming section 22-1 into two.

In the steam reforming, the catalyst deterioration is large especially in the first reforming section (in the present embodiment, the side of the first reforming section 22-1 near the fuel gas pipe 12-3). Therefore, if the catalyst is designed to be easily exchanged except for the first reforming portion, the maintenance becomes easy.

The air preheater 23 exchanges heat between the inner tube and the outer tube. The inner tube (high temperature side) has an oxidant gas pipe 2
The oxidant gas 52, which is connected to 6-3 and heat-exchanged in the second reforming section 22-2, flows. The oxidant gas 52, which is connected to the oxidant gas pipe 11-4 and is supplied to the fuel cell module main body 21, flows through the outer pipe (low temperature side). Thereby, the oxidant gas 52 supplied to the fuel cell module main body 21 is preheated. The oxidant gas 52 in the inner pipe is cooled and sent out from the oxidant gas pipe 11-5. The oxidant gas 52 in the outer tube is heated and sent to the fuel cell module main body 21 from the oxidant gas pipe 26-1.

The fuel cell module main body 21 includes a plurality of fuel cell cell tubes 33, an oxidant gas supply chamber 37, and a supply chamber 3.
8, a discharge chamber 39, and a heat insulator 40 (-1 to 2). The supply chamber 38 has a tube plate A34, a fuel gas supply port 38-1, and a plurality of first fitting portions 38-2. Discharge chamber 39
Has a tube plate B35, a fuel gas outlet 39-1 and a second fitting portion 39-2. Oxidant gas supply chamber 3
7 is a tube plate A34, a tube plate B35, an oxidant gas supply port 37
-1 and an oxidant gas discharge port 37-2. Note that the configuration of FIG. 1 omits the configuration relating to current collection in the present drawing.

Each configuration will be described in detail below.

The fuel cell cell tube 33 is a cylindrical base tube made of porous ceramics. The outer surface has a fuel cell 41 for generating power and a lead film 43 (described later). One end of the fuel cell tube 33 is a tube plate A34 of the supply chamber 38.
Is opened and fitted. Similarly, the other end is opened and fitted to the tube plate B35 of the discharge chamber 39.

The supply chamber 38 as the first fuel chamber is supplied with the fuel gas 51 from the fuel gas pipe 25-1 through the fuel gas supply port 38-1, and is evenly supplied to each of the plurality of fuel cell cell pipes 33. The fuel gas 51 is supplied to. It has a shape such as a hollow rectangular parallelepiped or a cylinder. Tube plate A3 forming the supply chamber 38
Each plate including 4 is made of metal. In this embodiment, it has a rectangular parallelepiped shape made of stainless steel.

The discharge chamber 39 as the second fuel chamber collects the spent fuel gas 51 discharged from the fuel cell cell pipe 33 and feeds it through the fuel gas discharge port 39-1.
The fuel gas 51 is sent to 5-2. It has a shape such as a hollow rectangular parallelepiped or a cylinder. Each plate including the tube plate B35 that forms the discharge chamber 39 is made of metal. In this embodiment, it has a rectangular parallelepiped shape made of stainless steel.

The oxidant gas supply chamber 37 as an air chamber is
From the oxidizing gas pipe 26-1 to the oxidizing gas supply port 37-1
The oxidant gas 52 is supplied to the fuel cell cell pipe 33 via the. Then, the used oxidant gas 52 is supplied to the oxidant gas pipe 26 through the oxidant gas outlet 37-2.
-2 to send. It is between (the tube plate A34 of) the supply chamber 38 and (the tube plate B35 of) the discharge chamber 39, and is isolated from them, and includes the fuel cell tube 33. Inside the vicinity of the tube sheet A34 and the tube sheet B35, the heat insulator 40 (heat insulator A40
-1 and the heat insulating body B40-2) are fixed. The room is made of metal such as stainless steel or heat-resistant alloy.

The tube plate A34, which is the first tube plate as one side surface of the supply chamber 38 (first fuel chamber), has holes (for that number) for connecting the fuel cell tubes 33. Then, it is connected to one end of the fuel cell tube 33 so that gas can flow in and out, and is opened and joined. Supply room 3
8 and the oxidizing gas supply chamber 37 are separated from each other.

The tube plate B35, which is the second tube plate as one side surface of the discharge chamber 39 (second fuel chamber), has holes (for that number) for connecting the fuel cell tubes 33. The other end of the fuel cell tube 33 is connected so that gas can flow in and out, and is open and joined. The discharge chamber 39 and the oxidizing gas supply chamber 37 are separated from each other.

The heat insulating body 40 includes a tube sheet A34 and a tube sheet B35.
Is fixed in the oxidant gas supply chamber 37 outside the supply chamber 38 and the discharge chamber 39. The tube sheet A34 side is the heat insulator A40-1, and the tube sheet B35 side is the heat insulator B40-2. The heat insulator B40-2 forms a flow path of the oxidant gas 52 together with the tube plate B35 in the vicinity of the end on the fuel cell tube 33, and restricts the flow thereof. In addition, the heat insulator 40 is the power generation unit 41 of the fuel cell tube 33.
The heat on the side (described later) is cut off, and the tube sheet A34 and the tube sheet B35,
Alternatively, the first fitting portion 38-2 and the second fitting portion 39-2
Is thermally protected. The heat insulator 40 is exemplified by a heat insulating material containing silica, alumina, magnesia or the like as a main component.

FIG. 6B shows a heat insulator 40 (heat insulator A40).
-1 and a heat insulator B40-2) are shown in a front view. Heat insulator 40
The holes 40-3 for the fuel cell tubes 33 are opened in a zigzag pattern. The diameter of the hole 40-3 of the heat insulating body B40-2 is
It is slightly larger than the diameter of the fuel cell tube 33. The gap between the fuel cell tube 33 and the hole of the heat insulator 40 is filled with the oxidant gas 52.
For passing through. Hole 40- of heat insulator A40-1
The diameter of 3'is substantially equal to the diameter of the fuel cell tube 33. This is because it is not necessary for the oxidizing gas 52 to pass through the gap.

However, the arrangement of the fuel cell tube 33 in the present invention is not limited to that shown in FIG. 6 (b).

Next, referring to FIG. 4, the fuel cell tube 3
The 3rd 2nd fitting part 39-2 and its periphery are demonstrated.

FIG. 4 is an enlarged sectional view of one second fitting portion 39-2 of the fuel cell tube 33 of FIG. 3 and its periphery. In the drawing, the configuration relating to the current collection is omitted.

The second fitting portion 39-2 is connected to the fuel cell 41.
A fuel cell cell tube 33 including a power generation part 42 and a lead film 43 ', a tube plate B35, a sealant 44', a second fitting ring 4
6'and filler 47 '. The heat insulator B40-2 restricts the flow of the oxidant gas 52 around it.

The fuel cell 41 is a fuel cell tube 33.
On the outer surface of the fuel cell. The fuel cells 41 are joined together by an interconnector film (not shown). Fuel gas 51 diffused from the inside of the fuel cell tube 33, and oxidant gas 52 supplied from the outside
Generate electricity by and.

The power generation section 42 is an area where a plurality of fuel battery cells 41 are provided on the fuel battery cell tube 33.

The lead film 43 ′ is a conductive film as one pole for guiding the electric power generated by the power generation section 42. In the same manner on the supply chamber 38 side, electric power is taken out from the electrodes drawn out from both films.

The sealant 44 'is the second fitting ring 46'.
Is a gas sealant filled in a region between the outer surface of the tube and the inner surface of the second fitting portion 39-2 of the tube sheet B35. Fuel gas 51 in the discharge chamber 39 and oxidant gas 52 in the oxidant gas supply chamber 37
Gas seal between Use a sealant that matches the maximum operating temperature around it.

When the surface of the second fitting ring 46 'and the inner surface of the second fitting portion 39-2 of the tube plate B35 are rubbed with each other with extremely high precision, the sealant may not be used. .

The second fitting ring 46 'is a cylindrical ring having an inner diameter slightly larger than that of the fuel cell tube 33. The outer surface thereof and the inner surface of the second fitting portion 39-2 of the tube sheet B35 are in close contact with each other. The second fitting ring 46 'and the filling material 47' act as a cushioning material and absorb the dimensional deviation and surface irregularities of the fuel cell tube 33.

The filling material 47 'is a gas sealant and an adhesive material filled in the region between the inner surface of the second fitting ring 46' and the outer surface of the fuel cell tube 33. The fuel gas 51 in the discharge chamber 39 and the oxidant gas 52 in the oxidant gas supply chamber 37 are gas-sealed. Further, the dimensional deviation of the fuel cell tube 33 is absorbed by the deformation. The method of embedding solder, adhesive, resin, etc. according to the maximum operating temperature around it can be used.

Since the heat insulator B40-2 is as described above, its explanation is omitted.

The tube plate B35 has a hole through which the second fitting ring 46 '(and the fuel cell tube 33) is inserted. The diameter of the hole of the second fitting portion 38-2 is the second fitting ring 46 '.
It is slightly smaller than the diameter of. By doing this,
As shown in FIG. 4, when the second fitting ring 46 'is passed through the hole, the inner peripheral portion of the hole of the tube sheet B35 is deformed inward in the direction of passing the second fitting ring 46'. The outer peripheral portion of the second fitting ring 46 'and the inner peripheral portion of the hole of the tube sheet B35 are in close contact with each other.

Now, the tube sheet B35 will be further described.

FIG. 6A shows a front view of the tube sheet B35. As shown in FIG. 6A, the tube sheet B35 has holes 49 for the second fitting ring 46 '(and the fuel cell tube 33) formed in a zigzag pattern. The diameter of each hole 49 is smaller than the outer diameter of the second fitting ring 46 '.

However, the arrangement of the fuel cell tube 33 in the present invention is not limited to that shown in FIG. 6 (a).

As a method of bringing the second fitting ring 46 'into close contact with the tube sheet B35, there are deep drawing processing and shrink fitting processing such as shrink fitting processing. The diameter of the hole 49 is smaller than the outer diameter of the second fitting ring 46 'so that an interference fitting process can be performed. However, when the fuel cell tube 33 is directly passed through without using the second fitting ring 46 ′, the diameter is made smaller than the outer diameter of the fuel cell tube 33.

When the inner peripheral portion of the hole 49 of the tube plate B35 comes into close contact with the second fitting ring 46 ', the inner peripheral portion of the tube plate B35 strongly adheres to the second fitting ring 46' due to the elastic force due to the interference fitting, and exhibits a gas sealing property. At the same time, it strongly holds the second fitting ring 46 '(and the fuel cell tube 33 connected thereto).

Since the second fitting portion 39-2 has a role of supporting the fuel cell tube 33, the tube sheet B35 is preferably made of a material having a certain strength. In addition, the joint portion (second fitting portion 39-2) does not allow gas to leak from the gap between the fuel cell tube 33 and the tube plate B35,
In addition, it is preferable that the member is an elastic member such as a metal plate so as to be able to absorb a positional displacement due to stress or the like and vibration or impact. At that time, since it is used in an oxidizing atmosphere at about 600 ° C., it is more preferable that the member can withstand the atmosphere. As such a material, a stainless metal material is preferable. More preferably, it is an austenitic stainless steel such as SUS304 or SUS316.

Further, since the upper limit of the thickness is a thickness that allows interference fitting, and the lower limit is a thickness that can support the fuel cell tube 33,
Each is determined experimentally. It depends on the type of board material. For example, in austenitic stainless steel,
It is preferably 1 mm or more and 2 mm or less. More preferably, it is 0.2 or more and 1 mm or less.

If the surface of the second fitting ring 46 'is made smooth, or if the sealant 44' is made to have lubricity (solid), the second fitting with the inner peripheral surface of the hole of the tube sheet B35 is made. It is also possible to cause the outer peripheral surface of the ring 46 'to slide (slide) with each other with a force of a certain magnitude or more. The magnitude of the force and the degree of sliding are experimentally determined based on the surface condition of the second fitting ring 46 ', the type of the sealant 44', and the like. When it becomes slidable, due to the difference in coefficient of thermal expansion,
Even if a difference in elongation occurs due to heat, it can be absorbed by slipping.

Next, referring to FIG. 5, the fuel cell tube 3
The 3rd 1st fitting part 38-2 and its periphery are demonstrated. FIG. 5 shows a first portion of one of the fuel cell tubes 33 of FIG.
It is sectional drawing which expanded the fitting part 38-2 and its periphery. In this drawing, regarding the configuration related to current collection,
Omitted.

The first fitting portion 38-2 is the fuel cell 41.
Fuel cell cell tube 3 including a power generation part 42 and a lead film 43
3, a tube sheet A34, a sealant 44, a first fitting ring 46, and a filler 47. The oxidant gas 52 around it is
It is restricted by the heat insulator A40-1 and does not reach the tube sheet A34.

The first fitting portion 38-2 and its periphery of the fuel cell tube 33 shown in FIG. 5 are the same as the second fitting portion 39-2 and its periphery of FIG. 4, and their explanations are omitted. To do. Since the heat insulator A40-1 is as described in FIG. 3, its description is omitted. The fuel battery cell tube 33 including the fuel battery cell 41 and the power generation unit 42 is as described in FIG. , The tube sheet A34, the lead film 43, the sealant 44, the first fitting ring 46 and the filler 47 are the tube sheet B35, the lead film 43 ', the sealant 44', the second fitting ring 46 'and the second fitting ring 46' of FIG. Since it is similar to the filler 47 ', the description thereof will be omitted.

In this embodiment, as shown in FIG. 4, the second fitting ring 46 'and the filler 47' are used. However,
Depending on the dimensional accuracy and surface finish of the fuel cell tube 33, it is possible to directly fit the tube plate B35 and the fuel cell tube 33 at the second fitting portion 39-2 without using them. . In that case, since the number of members is reduced, the component cost and the manufacturing cost can be reduced.

FIG. 7 shows the second case when the fitting ring is not used.
The expanded sectional view of the fitting part 39-2 and its periphery is shown.
The meanings of the respective symbols are the same as those in FIG.

Similarly, in this embodiment, as shown in FIG. 5, the first fitting ring 46 and the filler 47 are used. However, it is also possible to directly fit the tube plate A34 and the fuel cell tube 33 at the first fitting portion 38-2 without using them.

FIG. 8 shows the first case when no fitting ring is used.
The expanded sectional view of the fitting part 38-1 and its periphery is shown.
The meanings of the respective symbols are the same as those in FIG. 4, and the description thereof will be omitted.

Next, the operation of the embodiment of the fuel cell module of the present invention will be described with reference to FIG. 1, (FIG. 2) and FIG.

The oxidant gas 52 will be described.

The oxidant gas 52 is the oxidant gas pipe 11-
It is supplied to the gas turbine 2 via 1 and compressed by the compressor. Then, the oxidant gas 52 is supplied to the three-way valve 3 via the oxidant gas pipe 11-2. In the three-way valve 3, a part of the oxidant gas 52 is sent to the oxidant gas pipe 11-6 for combustion in the combustor 8 under the control of a control unit (not shown). Then, the remaining oxidant gas 52 is sent to the oxidant gas pipe 11-3. Oxidant gas 52 via oxidant gas pipe 11-3
Is supplied to the air compressor 4 and further compressed. Then, the oxidant gas 52 is supplied to the fuel cell module 1 via the oxidant gas pipe 11-4.

The oxidant gas 52 supplied to the fuel cell module 1 flows through the outer tube of the air preheater 23. At that time, it is preheated by exchanging heat with the high temperature oxidant gas 52 flowing through the inner pipe (for example, about 550 ° C.). The preheated oxidant gas 52 is delivered to the fuel cell module main body 21 from the oxidant gas pipe 26-1.

The oxidant gas 52 supplied to the fuel cell module main body 21 enters the oxidant gas supply chamber 37 through the oxidant gas supply port 37-1. Then, the flow path formed between the heat insulator B40-2 and the tube sheet B35 is moved along the tube sheet B35. At this time, the temperature of the oxidant gas 52 is about 550 ° C., which is an extremely low temperature as compared with the operating temperature (900 to 1000 ° C.) of the fuel cell unit 41. The tube sheet B35 is protected by the heat insulator B40-2 against the heat of the power generation section 42. Therefore, the tube sheet B
The level of heat resistance (oxidation resistance) of the material used for 35 can be lowered.

A plurality of fuel cell cell tubes 33 on the discharge chamber 39 side
The oxidant gas 52 that has reached either of the
In the vicinity of −2, it enters the hole 40-3 between the inner surface of the heat insulator B40-2 and the outer surface of the fuel cell tube 33. Hole 40-
The oxidant gas 52 passing through 3 exchanges heat with the fuel gas 51 passing through the inside of the fuel cell tube 33 through the base tube of the fuel cell tube 33. Then, the oxidant gas 52
Is heated to a temperature necessary for power generation (for example, about 850 ° C.) at the time of exiting from the hole 40-3. Further, the temperature is further raised by the time it reaches the power generation unit 42.

In the power generation section 42, the oxidant gas 52 is
It is supplied to the fuel cell 41 and contributes to power generation. At this time, the fuel cell 41 generates heat, but the heat is carried away by the oxidant gas 52, so that the temperature of the fuel cell 41 is maintained at 900 ° C to 1000 ° C. In addition, the oxidant gas 52 increases the temperature while drawing heat generated by the power generation from the fuel cell 41. Then, the used oxidant gas 52 reaches a high temperature (for example, 950 ° C.) and reaches the vicinity of the heat insulator A40-1. Oxidant gas 52
Moves substantially along the surface of the heat insulator A40-1 on the power generation section 42 side and reaches the oxidant gas discharge port 37-2. And
From there, it is delivered to the oxidant gas pipe 26-2.

The oxidant gas 52 supplied to the second reforming section 22-2 via the oxidant gas pipe 26-2 is the gas flow section 2
Pass 2-2c (high temperature side). At that time, the catalyst section 22-
Heat is exchanged with the fuel gas 51 flowing through 2b (low temperature side), the temperature is lowered (for example, about 700 ° C.), and the gas is delivered from the oxidant gas pipe 26-3.

The oxidant gas 52 supplied to the air preheater 23 via the oxidant gas pipe 26-3 passes through its inner pipe (high temperature side). At that time, heat is exchanged with the oxidant gas 52 passing through the outer pipe (low temperature side) to lower the temperature (for example, 55
(About 0 ° C.), and sent from the oxidant gas pipe 11-5.
The sent oxidant gas 52 is supplied to the combustor 8.

Next, the fuel gas 51 will be described.

The fuel gas 51 is supplied to the three-way valve 9.
In the three-way valve 9, a part of the fuel gas 51 is delivered to the fuel gas pipe 12-8 for combustion in the combustor 8 under the control of a control unit (not shown). Then, the remaining fuel gas 51 is delivered to the fuel gas pipe 12-2. The fuel gas 51 passing through the fuel gas pipe 12-2 is supplied to the primary fuel preheater 5. Then, in the primary fuel preheater 5, the fuel gas 51 (low temperature side) supplied via the fuel gas pipe 12-2 and the used gas supplied from the fuel cell module 1 via the fuel gas pipe 12-4. And the fuel gas 51 (on the high temperature side) exchange heat. Temperature rise (eg 5
The fuel gas 51 heated to about 50 ° C. is the fuel gas pipe 12
It is sent to the fuel cell module 1 via -3.

The fuel gas 51 supplied to the fuel cell module 1 via the fuel gas pipe 12-3 is supplied to the first reforming section 22.
-1 of the catalyst portion 21-1a is steam reformed. The energy used for the reforming is heat exchange with the fuel gas 51 that has been reformed in the second reforming section 22-2 that passes through the gas circulation section 22-1b (the catalyst section 21-1a is on the low temperature side, the gas circulation is low). Part 22-1
b is the high temperature side). The reformed fuel gas 51 (for example, a temperature of about 700 ° C.) is sent to the reforming pipe 27-1. The fuel gas 51 supplied to the second reforming section 22-2 via the reforming pipe 27-1 is supplied to the catalyst section 22-2b via the gas flow passage 22-2a. Then, in the catalyst section 22-2b, steam reforming is performed at a higher temperature than in the reforming section 22-1a. The energy used for the reforming is heat exchange with the oxidant gas 52 used in the fuel cell module main body 21 passing through the gas flow passage 22-2c (the catalyst portion 22-2b is at a low temperature side, the gas flow portion 22- 2c is obtained on the high temperature side). The reformed fuel gas 51 (for example, a temperature of about 750 ° C.) is sent to the reforming pipe 27-2.
The fuel gas 51 supplied to the first reforming section 22-1 via the reforming pipe 27-2 exchanges heat with the catalyst section 22-1a in the gas flow passage 22-1b (the catalyst section 21-1a has a low temperature side). ,
The gas distribution part 22-1b is operated on the high temperature side and the temperature is lowered.
Fuel gas 51 whose temperature has been lowered (for example, temperature is about 550 ° C.)
Is sent to the fuel gas pipe 25-1.

The fuel gas 51 supplied to the fuel cell module main body 21 via the fuel gas pipe 25-1 enters the supply chamber 38 through the fuel gas supply port 38-1 and spreads throughout the supply chamber 38. At this time, the temperature of the fuel gas 51 is 55
The temperature is 0 ° C. or lower, and the operating temperature of the fuel cell unit 41 (900
It is a very low temperature in comparison with (.about.1000 ° C.). In addition, the tube sheet A34 is a heat insulator A4 against the heat of the power generation unit 42.
Protected by 0-1. Therefore, the level of heat resistance (oxidation resistance) of the material used for the tube sheet A34 can be lowered.

The fuel gas 51 that has spread to the supply chamber 38 flows into the fuel cell cell pipe 33 from one end of the fuel cell cell pipe 33 at a uniform flow rate. The fuel gas 51 exchanges heat with the oxidant gas 52 flowing along the outer surface of the fuel cell tube 33 from the vicinity of the heat insulator A10-1 to the vicinity of the power generation section 42 via the base tube of the fuel cell tube 33. . Then, the temperature is raised to reach the vicinity of the power generation unit 42 (for example, the temperature is about 700 ° C.). Then, the temperature is further increased until the fuel cell 41 is reached.

In the power generation section 42, the fuel gas 51 is supplied to the fuel cell 41 and contributes to power generation. that time,
Although the fuel cell 41 generates heat, the heat is carried away by the oxidant gas 52 flowing on the outer surface of the fuel cell tube 33, so that the temperature of the fuel cell 41 is 900 ° C. to 100 ° C.
Hold at 0 ° C. The temperature of the fuel gas 51 does not rise, either. Used fuel gas 5 out of fuel gas 51
1 and steam generated by power generation are heat insulating materials B40-2
Reach near.

The fuel gas 51 flows from the vicinity of the heat insulator B40-2 to the vicinity of the second fitting portion 39-2 through the base tube of the fuel cell tube 33 along the outer surface of the fuel cell tube 33 at a low temperature. And heat exchange with the oxidant gas 52. Then, the temperature is lowered to reach the other end of the fuel cell tube 33 (for example, about 600 ° C.). Then, it is delivered from the other end to the discharge chamber 39.

The spent fuel gas 51 sent out is mixed in the discharge chamber 39. At this time, the temperature of the fuel gas 51 is 600 ° C. or lower, which is an extremely low temperature as compared with the operating temperature (900 to 1000 ° C.) of the fuel cell unit 41. The tube sheet B35 is protected by the heat insulator B40-2 against the heat of the power generation section 42. Therefore, the level of heat resistance (oxidation resistance) of the material used for the tube sheet B35 can be lowered. The fuel gas 51 in the discharge chamber 39 is delivered from the fuel gas discharge port 39-1 to the fuel gas pipe 25-2.

The fuel gas 51 sent to the fuel gas pipe 25-2 is supplied to the three-way valve 24 controlled by the control unit (not shown).
As a result, a part thereof is supplied to the fuel gas pipe 12-3. By recirculating the used fuel gas 51, the fuel utilization rate can be improved. The remaining fuel gas 51 is
It is delivered to the fuel gas pipe 12-4.

The fuel gas 51 passing through the fuel gas pipe 12-4 is supplied to the primary fuel preheater 5. In the primary fuel preheater 5, the fuel gas 51 (low temperature side) supplied via the fuel gas pipe 12-2 and the fuel gas pipe 1
The spent fuel gas 51 (high temperature side) supplied from the fuel cell module 1 via 2-4 exchanges heat. The fuel gas 51 whose temperature has been lowered (for example, about 550 ° C.) is supplied to the fuel gas pipe 12-5, the pump 6 and the fuel gas pipe 12-6.
It is sent to the three-way valve 7 via the via. In the three-way valve 7, part of the fuel gas 51 is controlled by a controller (not shown).
It is delivered to the fuel gas pipe 12-3 for the fuel cell module 1. Then, the remaining fuel gas 51 is delivered to the fuel gas pipe 12-7. The fuel gas 51 in the fuel gas pipe 12-7 is supplied to the combustor 8.

Next, the combustion gas 53 will be described.

The oxidant gas 52 supplied from the oxidant gas pipe 11-5 and the fuel gas 51 supplied from the fuel gas pipe 12-7 are mixed and burned in the combustor 8 to generate a combustion gas 53. . The combustion gas 53 is supplied to the gas turbine 2 via the combustion gas pipe 13-1. The combustion gas 53 passing through the combustion gas pipe 13-1 rotates the turbine of the gas turbine 2. This rotation causes the generator to operate. At the same time, the rotation drives the compressor, and the oxidant gas 52 (air in this embodiment) supplied through the oxidant gas pipe 11-1 is compressed. The used combustion gas 53 is discharged from the combustion gas pipe 13-2.

The combustion gas 53 discharged from the combustion gas pipe 13-2 passes through the combustion gas pipe 13-3 together with the oxidant gas 52 from the compressor of the gas turbine 2 via the oxidant gas pipe 11-7. It is delivered to the chimney 10. Then, it is discharged from there.

According to the present invention, the heat generated in the fuel cell 41 can be effectively used for heat exchange, reforming and the like in the fuel cell module 1. That is, in order to take out the generated heat to the outside of the fuel cell module 1 and use it effectively, it is not necessary to introduce a heat medium such as water for hot water supply. Therefore, it becomes unnecessary to connect pipes other than the pipes for the fuel gas 51 and the oxidant gas 52 to the fuel cell module 1. Therefore, the fuel cell module 1
The structure can be made simpler, and the manufacturing cost and the delivery time can be reduced.

Further, according to the present invention, the temperature of the fuel gas 51 supplied to the supply chamber 38 and the discharge chamber 39 can be kept low. That is, the heat resistance (oxidation resistance) of the tube sheet A34 of the supply chamber 38 and the tube sheet B35 of the discharge chamber 39 can be reduced. That is, a lower-grade material can be used, and the material cost and the manufacturing cost can be reduced.

(Embodiment 2) FIG. 1 is a configuration diagram showing a second embodiment of a combined power generation system to which the fuel cell module according to the present invention is applied. The combined power generation system includes a fuel cell module 1, a gas turbine 2, a three-way valve 3, an air compressor 4, a primary fuel preheater 5, a pump 6, a three-way valve 7, a combustor 8, a three-way valve 9 and a chimney 10.

Then, they are oxidant gas pipes 11-1.
11-11, fuel gas pipes 12-1 to 12-9, and combustion gas pipes 13-1 to 13-3.

Since each structure of FIG. 1 is the same as that of the first embodiment, its explanation is omitted.

Next, the fuel cell module 1 will be described.

FIG. 9 is a diagram (cross-sectional view) showing the configuration of the second embodiment of the fuel cell module according to the present invention.
The fuel cell module 1 includes a fuel cell module body 2
1, a reformer 22, an air preheater 23, and a fuel cooler 55. And, they are the fuel gas pipes 25-1, 2
5-3 and the oxidant gas pipes 26-1 to 26-4 are connected.

The reformer 22 performs steam reforming on the fuel gas 51 supplied through the fuel gas pipe 12-3. As the energy input to the reformer 22, the internal energy of the oxidant gas 52 sent from the fuel cell module 1 via the oxidant gas pipe 26-2 is used. Here, after the steam reforming, the fuel gas 51 becomes a gas containing hydrogen and carbon monoxide as main components. The reformed fuel gas 51 is sent to the fuel gas pipe 25-1.

The fuel cooler 55 includes the oxidant gas pipe 11-
The heat is exchanged between the oxidant gas 52 (low temperature side) supplied via No. 4 and the fuel gas 51 (high temperature side) supplied from the reformer 22 via the fuel gas pipe 25-1. The oxidant gas 52 on the low temperature side is heated and sent to the oxidant gas pipe 26-4. The high temperature side fuel gas 51 is cooled and sent to the fuel gas pipe 25-3.

The air preheater 23 is composed of an oxidant gas pipe 26-
The oxidant gas 52 (low temperature side) supplied via No. 4 and the oxidant gas 52 (high temperature side) supplied from the reformer 22 via the oxidant gas pipe 26-3 are heat-exchanged. The oxidant gas 52 on the low temperature side is heated and the oxidant gas pipe 26-1
Sent to. The oxidant gas 52 on the high temperature side is cooled and sent to the oxidant gas pipe 11-5.

When the fuel cooler 55 preheats the oxidant gas 52 sufficiently, the air preheater 23 may not be installed. In that case, piping is simplified, and equipment and manufacturing costs are reduced.

The fuel cell module main body 21 includes an oxidant gas 52 supplied through the oxidant gas pipe 26-1 and
Fuel gas 51 supplied through the fuel gas pipe 25-3
Generate electricity using and. The fuel gas 51 (including generated steam) used in the fuel cell module main body 21 is
It is delivered to the fuel gas pipe 12-4. The oxidant gas 52 (including the generated water vapor) not used in the fuel cell module main body 21 is delivered to the oxidant gas pipe 26-2.

Next, the fuel cell module 1 will be further described.

FIG. 10 is a sectional view showing in more detail the configuration of the second embodiment of the fuel cell module according to the present invention shown in FIG. The fuel cell module 1 includes a fuel cell module body 21, a reformer 22, and a fuel cooler 55. They are connected by fuel gas pipes 25-1 to 25-2 and oxidant gas pipes 26-1 to 26-3.
The air preheater 23 is not installed here.

The reformer 22 is the fuel cell module main body 2
It is installed adjacent to 1. The reformer 22 has a triple-tube structure including an inner tube including a gas flow section 22-a, an intermediate tube including a catalyst section 22-b, and an outer tube including a gas flow section 22-c.

The catalyst portion 22-b of the middle pipe is the fuel gas pipe 1
The fuel gas 51 supplied via 2-3 is steam-reformed by an internal catalyst. As the catalyst, a conventionally used steam reforming catalyst (eg nickel / alumina) can be used. Then, the fuel gas 51 containing hydrogen and carbon monoxide as main components by steam reforming is delivered to the tip of the outer tube. The tip of the outer tube is closed and the tip of the inner tube is open inside.

The gas flow section 22-c of the outer tube allows the oxidant gas 52 used in the fuel cell module body 21 to flow around the catalyst section 22-b. The oxidant gas 52 has a very high temperature and exchanges heat with the catalyst portion 22-b to release a part of internal energy to the catalyst portion 22-b. The energy is used to reform the reformer 22.
Then, the oxidant gas 52 is sent to the oxidant gas pipe 26-3.

The gas flow section 22-a of the inner pipe is the catalyst section 22.
-B is the fuel gas 51 reformed in the fuel gas pipe 25-1
Send to.

The fuel cooler 55 performs heat exchange between the inner pipe and the outer pipe. The fuel gas pipe 25 is provided on the inner pipe (high temperature side).
The fuel gas 51 is connected to -1 and reformed by the reformer 22 flows. The outer pipe (low temperature side) has an oxidant gas pipe 11-
4, the oxidant gas 52 supplied to the fuel cell module main body 21 flows. Thereby, the fuel gas 51 supplied to the fuel cell module main body 21 is cooled. At the same time, the oxidant gas 52 is preheated. The fuel gas 51 in the inner pipe is cooled and sent out from the fuel gas pipe 25-3. The oxidant gas 52 in the outer tube is heated and sent to the fuel cell module main body 21 from the oxidant gas pipe 26-4.

Regarding the fuel cell module main body 21,
The description is omitted because it is similar to the first embodiment.

Next, the operation of the embodiment of the fuel cell module of the present invention will be described with reference to FIG. 1, (FIG. 9) and FIG.

Here, the parts other than the fuel cell module 1 are the same as those in the first embodiment, and the description thereof will be omitted.

The oxidant gas 52 will be described.

The oxidant gas 52 supplied to the fuel cell module 1 via the oxidant gas pipe 11-4 flows through the outer pipe of the fuel cooler 55. At that time, heat is exchanged with the high temperature fuel gas 51 flowing through the inner pipe to be preheated (for example, 550).
℃). The preheated oxidant gas 52 is supplied from the oxidant gas pipe 26-4 (26-1) to the fuel cell module main body 2
Sent to 1.

The fuel cell module main body 21 and the oxidant gas 52 there are the same as those in the first embodiment, and the description thereof will be omitted.

The reformer 22 is supplied through the oxidant gas pipe 26-2.
The oxidant gas 52 supplied to the gas circulation unit 22-c
Pass through (high temperature side). At that time, heat exchange is performed with the fuel gas 51 flowing through the catalyst portion 22-b (low temperature side), the temperature is lowered (for example, about 600 ° C.), and the oxidant gas pipe 26-3
It is sent from (11-5). Delivered oxidant gas 5
2 is supplied to the combustor 8.

Next, the fuel gas 51 will be described.

The fuel gas 51 supplied to the fuel cell module 1 via the fuel gas pipe 12-3 is steam-reformed by the catalyst section 22-b of the reformer 22. The energy used for reforming is exchanged with the oxidant gas 52 used in the fuel cell module main body 21 passing through the gas flow passage 22-c (the catalyst portion 22-b is on the low temperature side, the gas flow portion 22- c is obtained on the high temperature side). Reformed fuel gas 51 (eg,
(A temperature of about 750 ° C.) is sent to the fuel gas pipe 25-1 via the gas flow passage 22-a.

The fuel cooler 5 is passed through the fuel gas pipe 25-1.
The fuel gas 51 supplied to No. 5 flows through the inner pipe of the fuel cooler 55. At that time, the temperature is lowered by exchanging heat with the low temperature oxidant gas 52 flowing through the outer tube (for example, about 600 ° C.). The temperature of the fuel gas 51 is reduced by the fuel gas pipe 25-
3 to the fuel cell module main body 21.

Since the fuel cell module main body 21 and the fuel gas 51 there are the same as those in the first embodiment,
The description is omitted.

Also in the second embodiment, as in the first embodiment,
The heat generated in the fuel cell 41 can be effectively used for heat exchange, reforming, etc. in the fuel cell module 1.
That is, in order to take out the generated heat to the outside of the fuel cell module 1 and use it effectively, it is not necessary to introduce a heat medium such as water for hot water supply. for that reason,
Fuel gas 51 and oxidant gas 5 are added to the fuel cell module 1.
There is no need to connect any pipe other than the pipe for 2. Therefore, the structure of the fuel cell module 1 can be further simplified, and the manufacturing cost and the delivery time can be reduced.

Further, according to the present invention, the temperature of the fuel gas 51 supplied to the supply chamber 38 and the discharge chamber 39 can be kept low. That is, the heat resistance (oxidation resistance) of the tube sheet A34 of the supply chamber 38 and the tube sheet B35 of the discharge chamber 39 can be reduced. That is, a lower-grade material can be used, and the material cost and the manufacturing cost can be reduced.

In the present invention, not only when the fuel cell tube 33 as shown in FIGS. 3 and 10 is vertically placed,
When placed horizontally (the fuel cell module 3 of FIG. 3 or FIG. 10)
3 can also be carried out by tilting sideways 90 degrees).

Further, the fuel cell tube 33 is supported at both ends. Therefore, the structure of the fuel cell tube 33 is simplified, maintenance is easy, and the cost is reduced.

[0164]

[Effects of the Invention] The heat generated in the fuel cell is effectively used for heating air in the fuel cell module and the air preheater while keeping the temperature of the wall surface of the tube sheet of the supply chamber in the fuel cell module low. To do.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of a combined power generation system to which a fuel cell module according to the present invention is applied.

FIG. 2 is a diagram (cross-sectional view) showing a configuration of a first embodiment of a fuel cell module according to the present invention.

FIG. 3 is a cross-sectional view showing the configuration of the fuel cell module in more detail.

FIG. 4 is an enlarged cross-sectional view of a second fitting portion for one fuel cell tube and its periphery.

FIG. 5 is an enlarged cross-sectional view of a first fitting portion for one fuel cell tube and its periphery.

FIG. 6 (a) is a front view of the tube sheet in the embodiment of the fuel cell module according to the present invention. (B) It is a front view of the heat insulator in the embodiment of the fuel cell module which is this invention.

FIG. 7 is an enlarged cross-sectional view of a second fitting portion and its periphery when a fitting ring is not used.

FIG. 8 is an enlarged cross-sectional view of a first fitting portion and its periphery when a fitting ring is not used.

FIG. 9 is a diagram (cross-sectional view) showing a configuration of a second embodiment of a fuel cell module according to the present invention.

FIG. 10 is a cross-sectional view showing the configuration of the fuel cell module in more detail.

FIG. 11 is a diagram showing an example of a schematic configuration of a conventional cylindrical solid oxide fuel cell module.

[Explanation of symbols]

1 Fuel cell module 2 gas turbine 3 three-way valve 4 air compressor 5 Primary fuel preheater 6 pumps 7 three-way valve 8 Combustor 9 three-way valve 10 chimney 11-1 to 11-7 Oxidant gas pipe 12-1 to 12-9 Fuel gas piping 13-1 to 13-3 Combustion gas piping 21 Fuel cell module body 22 reformer 22-a Gas distribution section 22-b Catalyst part 22-c Gas distribution section 22-1 First reforming unit 22-2 Second reforming section 22-1a Catalyst part 22-1b Gas distribution section 22-2a Gas distribution section 22-2b Catalyst part 22-2c Gas distribution section 23 Air preheater 24 three-way valve 25-1 to 25-3 Fuel gas piping 26-1 to 26-4 Oxidant gas piping 27-1 to 27-2 reforming pipe 33 Fuel cell tube 34 Tube Sheet A 35 Tube Sheet B 37 Oxidant gas supply chamber 37-1 Oxidant gas supply port 37-2 Oxidant gas outlet 38 supply room 38-1 Fuel gas supply port 38-2 1st fitting part 39 Discharge chamber 39-1 Fuel gas outlet 39-2 Second fitting part 40 heat insulator 40-1 Insulator A 40-2 Insulator B 40-3 hole 41 Fuel cell 42 Power Generation Department 43 (') lead film 44 (') sealant 46 First fitting ring 46 'second mating ring 47 (') filler 49 holes 51 Fuel gas 52 Oxidizer gas 53 Combustion gas 55 Fuel cooler 100 fuel cell module 101 Fuel gas 102 oxidant gas 103 Fuel cell tube 104 outer tube 105 inner tube 107 Oxidant gas supply chamber 108 supply room 109 discharge chamber 110 Fuel gas supply unit 112 Top plate 113 side plate 114 tube sheet 116 side plate 117 Tube Sheet 120 heat insulator 121 Side plate 122 Bottom plate

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H01M 8/12 H01M 8/12 // H02P 9/04 H02P 9/04 P (72) Inventor Yoshiaki Inoue 5-717-1, Fukahori-cho, Nagasaki-shi, Nagasaki Sanryo Heavy Industries Co., Ltd. Nagasaki Research Institute (72) Inventor Kurume Nagasei 1-1, Atsunoura-cho, Nagasaki-shi, Nagasaki Mitsubishi Heavy Industries Ltd. Nagasaki Shipyard (72) Inventor Katsumi Nagata 1-1 1-1 Atsunoura-cho, Nagasaki-shi, Nagasaki Mitsubishi Heavy Industries, Ltd. Nagasaki Shipyard F term (reference) 4G140 EA03 EA06 EB13 EB18 EB42 EB44 5H026 AA06 CV02 5H027 AA06 BA01 BA08 BA09 BA10 5H590 A28 CA08 CA08 CA08 CA28 CA08 CA26

Claims (11)

[Claims] 1. A reformer for reforming fuel gas, and a fuel cell module main body for generating electricity using the reformed fuel gas and oxidant gas. The fuel cell module uses the oxidant heat as the heat of the oxidant gas delivered from the fuel cell module body to perform the reforming. 2. The reformer is connected to a first reforming unit that reforms the fuel gas at a first temperature at a first temperature, and is connected to a rear stage of the first reforming unit. A second reforming unit that performs a second reforming of the burned fuel gas at a second temperature higher than the first temperature, wherein the second reforming unit uses the oxidant heat. And performing the second reforming, and the first reforming unit performs the first reforming by using fuel heat as heat of the fuel gas that has been subjected to the second reforming. The fuel cell module described in 1. 3. The air preheater for exchanging heat between the oxidant gas discharged from the reformer and the oxidant gas before being supplied to the fuel cell module body. Or the fuel cell module according to item 2. 4. The fuel cooler according to claim 1, further comprising a fuel cooler that exchanges heat between the reformed fuel gas and the oxidant gas before being supplied to the fuel cell module body. Fuel cell module. 5. A first pipe for supplying a first fuel gas; a first reformer connected to the first pipe for reforming the first fuel gas into a second fuel gas; A second pipe for delivering the second fuel gas from a quality part; and a second pipe connected to the second pipe for supplying the second fuel gas to the third pipe.
A second reforming section for reforming into fuel gas; and a third pipe including the first reforming section for delivering the third fuel gas from the second reforming section, the first modified section The reformer reforms the first fuel gas by utilizing the heat of the third fuel gas. 6. The second reforming section includes a double pipe having an inner pipe and an outer pipe including the inner pipe, and a modified pipe installed between an outer surface of the inner pipe and an inner surface of the outer pipe. A catalyst portion, and the outer pipe has a first end as one end connected to the third pipe, a second end as the other end closed, and the inner pipe has one end 6. The reformer according to claim 5, wherein the third end portion as is connected to the second pipe, and the fourth end portion as the other end portion is extended to the front side of the second end portion and opened. 7. The reformer according to claim 5 or 6, a fourth pipe connected to the third pipe for supplying the third fuel gas, the fourth pipe, and supplying an oxidant gas. A fuel cell module main body connected to a fifth pipe for generating electricity using the third fuel gas and the oxidant gas, the reformer being installed in the vicinity of the fuel cell module main body. The second reforming section of the reformer further comprises a gas flow section provided so as to cover the outer tube, and the oxidant gas supplied from the fuel cell module body to the gas flow section. A fuel cell module for reforming the second fuel gas into the third fuel gas using the heat of the. 8. A sixth pipe for delivering the oxidant gas from the reformer, the oxidant gas delivered from the reformer, installed near the fuel cell module body, and the fuel cell module. The fuel cell module according to claim 7, further comprising: an air preheater that exchanges heat with the oxidant gas before being supplied to the main body. 9. The fuel cell module main body has a plurality of fuel cell cell pipes having fuel cell cells formed on the surface thereof, and the fourth pipe connected to the plurality of fuel cell cell pipes. A first fuel chamber for supplying the first fuel chamber, a second fuel chamber for discharging spent fuel gas in the plurality of fuel cell cell pipes from the third fuel gas, the fifth pipe, and the first fuel chamber. An air chamber that is installed between a chamber and the second fuel chamber, includes the plurality of fuel cell tubes, and supplies the oxidant gas to the fuel cells, the first fuel chamber An end portion of the plurality of fuel cell tubes is opened to a first tube sheet as one side surface of the first fuel chamber and includes a plurality of fitted first fitting portions, and the second fuel chamber is The other end of each of the plurality of fuel cell tubes is a second side surface of the second fuel chamber. The fuel cell module according to claim 7, further comprising a plurality of second fitting portions that are opened and fitted to the tube sheet. 10. A reformer connected to a pipe for supplying a fuel gas to reform the fuel gas, a pipe for delivering the reformed fuel gas from the reformer, and an oxidant gas supply A fuel cooler connected to the pipe for performing heat exchange between the reformed fuel gas and the oxidant gas; a pipe for delivering the heat-exchanged fuel gas from the fuel cooler; A fuel cell module main body that is connected to a pipe for delivering the exchanged oxidant gas, and that generates electricity using the heat-exchanged fuel gas and the heat-exchanged oxidant gas; The quality control device and the fuel cooler are installed near the fuel cell module body, and the reformer uses the heat of the oxidant gas sent from the fuel cell module body to modify the fuel gas. Quality, fuel cell Yuru. 11. A gas turbine having a generator for compressing an oxidant gas, and power generation using the compressed oxidant gas and a fuel gas. The fuel cell module according to claim 1, and a combustor that combusts the fuel gas and the oxidant gas that have been used in the fuel cell module, and the gas turbine includes combustion generated by the combustor. A combined power generation system in which the compression is performed using gas to drive the generator.