JPH08287939A - Solid electrolyte fuel cell module - Google Patents

Abstract

PURPOSE: To eliminate a malfunction so far caused in a lower tube plate, and reduce capacity in an air heat exchanger. CONSTITUTION: A radiation converting body 101 of a porous body is arranged, between a lower tube plate 11 and a lower power generation chamber 1, and an air supply chamber 102 whose upper part is partitioned by the lower tube plate 11 and lower part is partitioned by the radiation converting body 101 respectively, is arranged between a fuel discharge chamber 5 and the power generation chamber 1. An air supply pipe 104 is arranged to connect this air supply chamber 102 and an air heat exchanger 103 to preheat supply air SA by using exhaust air EA from the power generation chamber 1. The supply air SA is supplied to the air supply chamber 102 by this air supply pipe 104, and is passed through the inside of the radiation converting body 101 from the air supply chamber 102, and is heated, and is supplied to the power generation chamber 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention protects a lower tube sheet which defines a fuel discharge chamber installed above a power generation chamber, which has a high operating temperature, from high temperature, and effectively radiates heat from the power generation chamber. The present invention relates to a solid electrolyte fuel cell module that can be used for

[0002]

2. Description of the Related Art A solid electrolyte fuel cell module has a high operating temperature of 800 ° C. to 1000 ° C., and a plurality of solid electrolyte fuel cells having a fuel electrode inside a cylindrical electrolyte and an air electrode outside. A cylindrical solid electrolyte fuel cell stack (hereinafter simply referred to as a stack), which is connected in series and closed at one end, is arranged vertically, and the power generation chamber that uses the supplied fuel and air to generate electricity is maintained at a high temperature. There is a need to. Therefore, the outer periphery of the container provided inside the power generation chamber is covered with a heat insulating material, and regenerated heat is exchanged with the exhaust air discharged from the power generation chamber by using the air heat exchanger. In addition to preheating the supply air, a radiant converter is provided below the power generation chamber in the container, and the radiant converter heated by the heat radiated from the high temperature stack is preheated by the air heat exchanger to generate power. The supply air that is being introduced into the chamber is heated.

FIG. 2 is a sectional view showing such a conventional solid electrolyte fuel cell module. In the figure, a power generation chamber 1 is provided inside a container 12 whose outer periphery is covered with a heat insulating material 9.
However, the upper part is partitioned by the lower tube sheet 11, and the lower part is partitioned by the radiation converter 07. In this power generation chamber 1, a plurality of solid-state electrolyte fuel cells, each having a fuel electrode inside and an air electrode disposed outside with an electrolyte interposed, are connected in series, and a large number of cylindrical stacks 2 each having a closed lower end are vertically arranged. It is arranged in a state. Further, inside the container 12 above the power generation chamber 1 whose upper portion is partitioned by the lower tube sheet 11, the lower tube sheet 11 and the upper tube sheet 10 provided above the lower tube sheet 11 are spaced apart from each other. The fuel discharge chamber 5 partitioned by the
The fuel supply chambers 3 whose lower portions are divided by 0 are respectively defined. An air heat exchanger 6 is provided inside the container 12 below the power generation chamber 1 whose lower portion is partitioned by the radiant converter 7 and at a distance from the radiant converter 7.

Fuel gas SF is supplied to the fuel supply chamber 3 from the outside.
A fuel introducing pipe 13 for supplying the fuel gas SF to the container 12 is connected by the fuel introducing pipe 13.
Is supplied to the fuel supply chamber 3 provided at the upper end of the. Also,
A fuel supply pipe 4 is installed at the axial center of the cylindrical stack 2, and its upper end communicates with the fuel supply chamber 3 and its lower end communicates with the closed lower end of the stack 2. . The fuel gas SF is supplied from the fuel supply chamber 3 to the fuel supply pipe 4
It is supplied to the lower end of the stack 2 through
When ascending along the outer peripheral surface of the fuel supply pipe 4 installed at the axial center portion of the stack 2, after being used for power generation reaction in the fuel electrode provided inside the stack 2, it becomes exhausted fuel EF and becomes After passing through the lower tube sheet 10 having an opening at the upper end, they are collected in the fuel discharge chamber 5 and exhausted from the inside of the container 12 by the fuel discharge pipe 14 provided in the fuel discharge chamber 5.

Also, the stack 2 together with the fuel gas SF
The supply air SA used for power generation in the above is supplied to the air heat exchanger 6 from the outside by the air introduction pipe 15.
The air heat exchanger 6 includes exhaust air E heated in the power generation chamber 1.
In order to discharge A into the container 12, the air discharge pipe 8 hanging from the power generation chamber 1 is connected. The supply air SA supplied through the air introduction pipe 15 is preheated by regenerating heat exchange with the exhaust air EA discharged from the power generation chamber 1 through the air discharge pipe 8. The supply air SA preheated by the air heat exchanger 6 is supplied below the radiation conversion body 07 formed of a porous material that defines the lower portion of the power generation chamber 1. The radiation converter 07 receives the heat radiated from the stack 2 and has a high temperature,
The preheated supply air SA passing through the inside from below to above is further heated.

As described above, the heat generated in the power generation chamber 1 is used to further heat the supply air SA which has been preheated in the radiant converter 7 by the air heat exchanger 6. The temperature rise width of the air can be suppressed and the temperature difference inside the power generation chamber 1 can be reduced. Further, when the supply air SA that has passed through the radiation conversion body 7 and is supplied into the power generation chamber 1 rises along the outer peripheral surface of the stack 2, which is vertically arranged in the power generation chamber 1, It is used for power generation reaction in an air electrode provided outside the air conditioner 2, and cools the inside of the power generation chamber 1. It is also used for power generation in the power generation room 1,
The exhaust air EF heated to ˜1000 ° C. is collected in the above-mentioned air exhaust pipe 8, exhausted to the air heat exchanger 6 and used for preheating the supply air SA, and then the outside of the container 12 by the air exhaust pipe 16. Exhausted to.

As described above, the power generation chamber 1 must be maintained at a high temperature of 900 to 1000 ° C. for power generation in the stack 2. As described above, the outer periphery of the container 12 that houses the power generation chamber 1 therein. The heat is kept by the heat insulating material 9 for encapsulating so that the high temperature is maintained. Further, the lower tube sheet 10 that partitions the upper portion of the power generation chamber 1 supports the stack 2 that is vertically arranged in the power generation chamber 1, and at the same time, the exhaust fuel EF in the fuel discharge chamber 5 and the inside of the power generation chamber 1 It prevents the supply air SA or the exhaust air EA from being mixed and burned. Further, the upper tube sheet 11 that divides the fuel discharge chamber 5 together with the lower tube sheet 10 and the lower portion of the fuel supply chamber 3 that is installed at the upper end of the container 12 is provided with the fuel supply that is hung at the axial center of the stack 2. The pipe 4 is supported and serves as a partition wall between the fuel supply chamber 3 and the fuel discharge chamber 5 to form a fuel gas SF and an exhaust fuel E.
Mixing with F is prevented.

In such a conventional solid electrolyte fuel cell module, as described above, the stack 2 is formed in the power generation chamber 1.
800-1000 operating temperature required for power generation in
The lower tube sheet 11 that supports the stack 2 in the power generating chamber 1 is provided adjacent to and above the power generating chamber 1, so that the stack 2 is exposed to the high temperature in the power generating chamber 1. become. Therefore, in particular, the temperature of the lower tube sheet 11 becomes high, the strength is lowered, and in order to support a large number of stacks 2, there are problems such as thickening and the use of high-grade materials.

[0009]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems of the conventional solid oxide fuel cell module by reducing the temperature rise of the lower tube sheet and radiating heat from the power generating chamber to the power generating chamber. An object of the present invention is to provide a solid oxide fuel cell module that can be more effectively used for heating supplied supply air and has improved thermal efficiency.

[0010]

Therefore, the solid electrolyte fuel cell module of the present invention has the following means.

A plurality of solid electrolyte fuel cells each having a power generation chamber defined inside a container surrounded by a heat insulating material and vertically installed in the power generation chamber and having a fuel electrode inside and an air electrode outside through an electrolyte. Cylindrical stack connected in series and closed at the lower end, fuel supply chamber defined above the power generation chamber inside the container, partitioned between the power generation chamber and the fuel supply chamber, and the upper end of the stack was opened The fuel discharge chamber, one end of which is opened to the fuel supply chamber and the other end of which is opened to the inside of the lower end of the stack.The fuel supply pipe is inserted inside the stack, and is installed below the power generation chamber inside the container. In a solid oxide fuel cell module comprising an air heat exchanger for preheating supply air to be supplied, (1) Air supply whose upper part is partitioned by a lower tube plate which partitions a fuel discharge chamber formed above the power generation chamber. Power generation by dividing the lower part of the room A radiation converter formed of a porous material, which forms an air supply chamber between the chamber and the fuel discharge chamber, is provided in the container above the power generation chamber.

(2) The air heat exchange installed in the container below the power generation chamber and the air supply chamber are connected to each other, and the supply air preheated by the air heat exchange is passed downward from above the radiation converter. For further heating, an air supply pipe for transferring to the air supply chamber was provided inside the power generation chamber.

[0013]

In the solid electrolyte fuel cell module of the present invention, the supply air after preheating which is lower than the temperature in the power generation chamber can be supplied directly below the lower tube sheet by means of the above-mentioned means (1) and (2). Lower the temperature of the lower tube sheet. As a result, the lowering of the stress of the lower tube sheet can be reduced, the thickening of the lower tube sheet or the use of a high-grade material with less stress lowering due to high temperature can be avoided, the cost can be reduced, and the weight can be made compact. Further, the radiant converter is installed between the lower tube sheet and the power generation chamber, and the preheated supply air supplied to the air supply chamber is passed through the inside of the radiant converter to be heated and supplied to the power generation chamber. As a result, the temperature of the air supplied to the power generation chamber can be raised, or the capacity of the air heat exchanger can be reduced and downsized.

[0014]

Embodiments of the solid oxide fuel cell module of the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view showing an embodiment of the solid oxide fuel cell module of the present invention. The same members as those shown in FIG. 2 are designated by the same reference numerals and detailed description thereof is omitted.

In the figure, reference numeral 101 denotes a radiation converter provided inside the container 12 above the power generation chamber 1, and a lower tube sheet 1 for partitioning the lower side of a fuel discharge chamber 5 formed above the power generation chamber 1.
1, the air supply chamber 102 is defined and formed between the power generation chamber 1 and the fuel discharge chamber 5. The radiation converter 101 is formed of a porous material such as ceramic. Reference numeral 103 denotes an air heat exchanger, which has substantially the same structure as the air heat exchanger 06 shown in FIG. 2, but the air heat exchanger 103 according to the present embodiment.
Then, the preheated supply air SA is not directly discharged to the power generation chamber 1, but is transferred to the air supply chamber 102 by the air supply pipe 104 installed upright in the power generation chamber 1 and the exhaust air EA descending in the power generation chamber 1 Is directly taken into the inside to preheat the supply air SA.

In this embodiment, only the structure different from that of the conventional solid oxide fuel cell module shown in FIG. 2 has been described above. Since the present embodiment is configured as described above, the fuel gas SF supplied from the outside to the fuel supply chamber 3 through the fuel introduction pipe 13 separates the fuel supply chamber 3 and the fuel discharge chamber 5 from the upper portion. A plurality of solid electrolyte fuel cells, each having a fuel electrode inside and an air electrode outside, are connected in series through a fuel supply pipe 4 whose upper end is supported by a tube plate 10 to form a fuel discharge chamber 5 and an air supply chamber 102. The upper end is supported by the lower tube sheet 11 for partitioning, and is introduced into the lower end of the cylindrical stack 2 suspended in the power generation chamber 1.

The lower end of the cylindrical stack 2 is closed, and the fuel gas SF introduced into the lower end is in the stack 2.
While being used for the power generation reaction in the fuel electrode provided inside the fuel cell, it rises and becomes exhausted fuel EF, which flows into the fuel exhaust chamber 5 where the upper end of the staff 2 is opened. Then, it is discharged to the outside of the container 12 by the fuel discharge pipe 14 provided in the fuel discharge pipe 5. This fuel gas SF and exhaust fuel EF
2 is introduced into the container 12 in the same manner as in the conventional example shown in FIG.

Next, the supply air SA is supplied to the air heat exchanger 10 provided at the lower end of the container 12 by the air introduction pipe 15.
3 is supplied. In the air heat exchanger 103, exhaust air EA that descends in the power generation chamber 1 and flows into the air heat exchanger 103,
That is, the exhaust air EA and the supply air S, which are used for the power generation reaction in the air electrode or the cooling inside the power generation chamber 1 and have a high temperature, are supplied.
Heat exchange between A. The air heat exchanger 103 performs regenerative heat exchange with the exhaust air EA, and the preheated supply air SA is supplied with the air supply pipe 10 penetrating the power generation chamber 1.
4 to the air supply chamber 10 installed below the lower tube sheet 11.

Supply air SA supplied to the air supply chamber 10.
Is when passing through the radiant converter 12 heated by the radiant heat from the power generation chamber 1 after cooling the lower tube plate 11 from the lower surface while flowing between the lower tube plate 11 and the radiant converter 12. Further, it is heated and supplied to the upper side of the power generation chamber 1. Further, when the supply air SA supplied from above to the power generation chamber 1 descends along the outer periphery of the stack 2, it causes a power generation reaction with an air electrode provided outside the stack 2 to generate power.
Exhaust air EA heated to 0 to 1000 ° C. flows into the air heat exchanger 103 provided below the power generation chamber 1.
The supply air SA is used not only for the power generation reaction described above, but also for cooling the inside of the container 2 that is heated by the high temperature generated by the power generation of the stack 2, for example, the lower tube sheet 11 and the power generation chamber 1 described above. used. The exhaust air EA that has flowed into the air heat exchanger 103 exchanges heat with the supply air SA and is exhausted to the outside of the container 12 by the air exhaust pipe 16 as described above.

As described above, in the solid electrolyte fuel cell module of this embodiment, the supply air SA after preheating, which is lower than the temperature in the power generation chamber 1, is supplied immediately below the lower tube sheet 11, and the lower tube sheet 11 is supplied. By lowering the temperature of the lower tube sheet, it is possible to reduce the stress drop of the lower tube sheet 11 in which the stress drops due to the high temperature, and it is possible to avoid the thickening of the lower tube sheet 11 or the use of a high-grade material with less stress drop due to high temperature The cost can be reduced and the lower tube sheet 11 can be reduced in weight.

The radiant converter 101 is installed between the lower tube sheet 11 and the power generation chamber 1, and the preheated supply air supplied to the air supply chamber 102 is passed through the inside of the radiant converter 101. The temperature of the supply air SA to the power generation chamber 1 can be raised by heating and supplying the power to the power generation chamber 1. In other words, this means that the capacity of the air heat exchanger 103, which has a large capacity and is required to supply the supply air SA having the predetermined temperature to the power generation chamber 1, can be reduced, and the lower part described above can be used. In combination with the weight reduction of the tube sheet 11, the solid electrolyte fuel cell module can be downsized.

[0022]

As described above, according to the solid oxide fuel cell module of the present invention, the following effects can be obtained with the configuration shown in the claims.

(1) The supply air preheated by the air heat exchanger is lower than the temperature in the power generation chamber, and since the lower tube sheet is cooled by this supply air, stress reduction due to high temperature can be dealt with. The lower tube sheet, which required to be fleshed and used of high-quality materials, can be made lighter and the cost can be reduced.

(2) The radiation converter installed between the power generation chamber and the lower tube sheet recovers the radiant heat from the power generation chamber and heats the supply air, so that the temperature supplied to the power generation chamber can be increased. Alternatively, it is possible to miniaturize the air heat exchanger for preheating the supply air of a predetermined temperature to supply it to the power generation chamber.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an embodiment of a solid oxide fuel cell module of the present invention.

FIG. 2 is a side sectional view showing an example of a conventional solid oxide fuel cell module.

[Explanation of symbols]

 1 Power Generation Chamber 2 Stack 3 Fuel Supply Chamber 4 Fuel Supply Pipe 5 Fuel Discharge Chamber 8 Air Discharge Pipe 9 Heat Insulation Material 10 Upper Tube Plate 11 Lower Tube Plate 12 Container 13 Fuel Inlet Pipe 14 Fuel Outlet Pipe 15 Air Inlet Pipe 16 Air Outlet Pipe 101 Radiation converter 102 Air supply chamber 103 Air heat exchanger 104 Air supply pipe 06 Air heat exchanger 07 Radiation converter SA Supply air EA Exhaust air SF Fuel gas EF Exhaust fuel

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsumi Nagata 1-1, Atsunouramachi, Nagasaki City Mitsubishi Heavy Industries Ltd. Nagasaki Shipyard Co., Ltd.

Claims (1)

[Claims] 1. A solid electrolyte fuel cell in which a power generation chamber defined inside a container surrounded by a heat insulating material, and a fuel electrode disposed vertically in the power generation chamber and having an electrolyte inside and a fuel electrode inside and an air electrode outside. A plurality of connected in series, a cylindrical stack having a closed lower end, a fuel supply chamber defined above the power generation chamber in the container, partitioned between the power generation chamber and the fuel supply chamber, A fuel discharge chamber having an upper end of the stack opened, a fuel supply pipe having one end opened to the fuel supply chamber and the other end opened to the inside of the lower end of the stack, and the fuel supply pipe inserted into the stack. In the solid electrolyte fuel cell module, which is installed in the lower part of the power generation chamber and has an air heat exchanger that preheats the supply air to be supplied to the power generation chamber, the solid electrolyte fuel cell module is installed above the power generation chamber and is connected to the fuel discharge chamber. Form an air supply chamber between A solid electrolyte fuel cell module, comprising: a porous radiant converter and an air supply pipe for transferring supply air preheated by the air heat exchanger to the air supply chamber.