JP2001185186A - Combustion device, reformer, and power generating system for solid polymeric fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a combustion device, a reformer, and a power generating system for solid polymeric fuel cell, which are capable of burning a low calorie gas and a high calorie gas without preparing a pre-mixing chamber. SOLUTION: The whole apparatus is composed of: a burner head 301, which is composed of a flame aperture 321 on the outer peripheral wall and a combustion chamber 323 inside the wall; the first lead-in pipe 324A, in which high calorie gas is led into the combustion chamber 323 of the burner head; and the second lead-in pipe 324B, in which low calorie gas is led into the combustion chamber 323 of the burner head. By selectively or previously mixing the gases of different calories using the common aperture 321, the combustion becomes possible.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion apparatus and a reformer for burning high calorie and low calorie gases, and a polymer electrolyte fuel cell power generation system.

[0002]

2. Description of the Related Art In recent years, in a state of being constantly heated by a combustion device,
A reformer for chemically reacting fuel gas such as natural gas, city gas, methanol, etc. to reform hydrogen, a CO converter for converting carbon monoxide, and a CO remover for removing carbon monoxide,
There has been proposed a polymer electrolyte fuel cell power generation system including the above-described fuel cell that generates power using hydrogen.

[0006] As shown in FIG. 6, the above-described combustion apparatus has a burner case 150, and a burner head 151 above the burner case 150. This burner head 15
The inside of 1 is a combustion chamber 152, in which a first flame hole 156 faces a central portion of the combustion chamber 152, and a second flame hole 158 faces a peripheral portion.

When a high calorie gas such as natural gas, city gas, or methanol is introduced through the high calorie gas introduction pipe 153, the combustion of the high calorie gas causes
A flame 156a is formed in the first flame hole 156. Also,
When a low-calorie gas (unreacted gas in the fuel cell) is introduced through the low-calorie gas introduction pipe 154, the flame 15 enters the second flame hole 158 by the combustion of the low-calorie gas.
8a are formed. The high-calorie gas is introduced into the premixing chamber 155, where it is premixed with the primary air 154 and then enters the combustion chamber 152 through the first flame hole 156, where the secondary air 1
57 and burns.
a is formed. The low calorie gas enters the combustion chamber 152 directly through the second flame 158 where the secondary air 157
And a flame 158 a is formed in the second flame hole 158.

[0005]

The above-described conventional combustion apparatus has a problem in that when burning low-calorie gas, the outer wall of the burner case 150 becomes hot because the flame 154a is formed on the peripheral edge. Two types of flame holes, a first flame hole 156 for burning high calorie gas and a second flame hole 158 for burning low calorie gas, are required, and the cost increases due to the formation of two kinds of flame holes. There is a problem of doing. Premixing chamber 1 for burning high calorie gas
Since 55 is required, there is a problem that flashback easily occurs.

Accordingly, an object of the present invention is to provide a combustion apparatus and a reformer capable of burning low calorie gas and high calorie gas without providing a premixing chamber, and a polymer electrolyte fuel cell power generation system. It is in.

[0007]

According to the first aspect of the present invention,
A burner head having a flame hole in the outer peripheral wall and having a combustion chamber inside; a first inlet pipe for introducing high-calorie gas into the combustion chamber of the burner head; A second introduction pipe for introducing gas, wherein the gases having different calories are selectively or premixed using a common flame hole so as to be combustible.

According to a second aspect of the present invention, in the first aspect, the burner head is incorporated concentrically in the burner case, and an annular cooling air passage is formed between the burner case and the burner head. It is characterized by the following.

According to a third aspect of the present invention, in the first or second aspect, the flame hole is a vertically long slit or a circular hole.

According to a fourth aspect of the present invention, there is provided a reformer for reforming a fuel gas such as natural gas or city gas into hydrogen by chemically reacting the fuel gas in a state where the combustion device is constantly heated. A burner head having a flame hole in the wall and a combustion chamber inside, a first inlet pipe for introducing high calorie gas to the combustion chamber of the burner head, and a low calorie gas in the combustion chamber of the burner head; And a second introduction pipe for introducing the gas having different calories, using a common flame hole to selectively or premix the gases so as to be combustible.

According to a fifth aspect of the present invention, a reformer for reforming a fuel gas such as a natural gas or a city gas into a hydrogen by chemically reacting the same in a state of being constantly heated by a combustion device, and converting carbon monoxide. In a polymer electrolyte fuel cell power generation system comprising a CO converter, a CO remover for removing carbon monoxide, and a fuel cell for generating electricity with hydrogen, the combustion device has a flame hole on an outer peripheral wall. A burner head having a combustion chamber inside thereof, a first inlet pipe for introducing the high-calorie fuel gas to the combustion chamber of the burner head, and a low-pressure pipe returned from the fuel cell to the combustion chamber of the burner head. A second introduction pipe for introducing an unreacted gas of calories, wherein the gas having different calories is selectively or premixed by using a common flame hole so as to be combustible.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 100 denotes a building. Commercial power is supplied to the building 100 via a low-voltage lamp 101, a watt-hour meter 102, and a distribution board 103. This commercial power is supplied to the air conditioner 105 and the television 106 via the first cable 104 shown by a thin line.
And so on.

On the other hand, in the present embodiment, a polymer electrolyte fuel cell power generation system (polymer electrolite fuel cell: PE) constituting a small household power supply system
FC device) S is installed outside the house 100.

As shown in FIG. 2, the small household power supply system S includes a heat recovery device in addition to the PEFC device. This heat recovery device has a hot water storage tank 112 and an ion exchange resin 125, and city water is supplied to the ion exchange resin 125 through a water pipe. This city water is made into pure water by the ion-exchange resin 125, and is supplied to a water tank 21 described later.
(FIG. 3). The PEFC device has a fuel supply device (reformer, CO shift converter, CO remover) 121.

The fuel supply device 121 is supplied with a fuel gas such as natural gas, city gas, methanol, LPG, butane and the like, and further includes a water tank 21 (FIG. 3) described later.
Is supplied to produce hydrogen. This hydrogen is supplied to the fuel cell 6, where the hydrogen is chemically reacted with oxygen in the air to generate power. Reference numeral 123 denotes a control device that controls power generation.

This power is boosted to 180 V via a DC / DC converter 124, and
11 and from there, through a second cable 107 shown in bold lines in FIG.
It is supplied to the refrigerator 110 and the like. This fuel cell power generation system S is connected to a commercial power supply via a system interconnection inverter 111.

In this small power supply system S, heat is generated in the process of power generation, and this heat is used to generate hot water from city water. As shown in FIG.
To store. This hot water is supplied to a bath 11 as shown in FIG.
3. It is supplied to the kitchen 114 and the like. This hot water tank 112
Is installed outside the house 100.

Next, a polymer electrolyte fuel cell power generation system (small household power supply system) S according to this embodiment will be described with reference to FIG.

In this small household power supply system S, a fuel gas 1 such as natural gas, city gas, methanol, LPG, butane or the like is supplied to a desulfurizer 2, where sulfur components are removed from the fuel gas. The fuel gas that has passed through the desulfurizer 2 is boosted in pressure by the booster pump 10 and supplied to the reformer 3. In this reformer 3, a reformed gas containing hydrogen, carbon dioxide, and carbon monoxide is generated. The gas that has passed through the reformer 3 is supplied to a CO converter 4, where carbon monoxide contained in the reformed gas is converted into carbon dioxide.

The gas that has passed through the CO converter 4 is supplied to a CO remover 5, where the unconverted carbon monoxide in the gas that has passed through the CO converter 4 is removed.

The hydrogen from the CO remover 5 from which the carbon monoxide has been removed is supplied to the polymer electrolyte fuel cell 6. The fuel cell 6 includes a fuel electrode (anode) 6
a, an air electrode (cathode) 6b, and a cooling unit 6c, and the hydrogen is supplied to the anode 6a. The hydrogen reacts with the oxygen contained in the air supplied to the cathode 6b via the fan 11 to generate electric power.

The reformer 3 has a burner 12 to which raw fuel is supplied through a pipe 13 and a fan 14.
And the unreacted hydrogen that has passed through the anode 6a via the pipe 15.

When the system is started, the raw fuel is supplied to the burner 12 through the pipe 13 and the fan 14
When the system is stabilized after startup, the supply of raw fuel is cut off, and the unreacted hydrogen via the anode 6 a is supplied to the burner 12 via the pipe 15.

In the reformer 3, the CO shift converter 4, the CO remover 5, and the fuel cell 6, a chemical reaction having a predetermined reaction temperature is performed. Since the chemical reaction in the reformer 3 is an endothermic reaction, the chemical reaction is performed while constantly heating with the burner 12.

Since the chemical reaction performed in the CO converter 4 and the CO remover 5 is an exothermic reaction, for example, in the CO remover 5, a burner (not shown) is burned only when the system is started, and the combustion gas is burned. Is generated, and the temperature of the CO remover 5 is raised to the reaction temperature by the heat of the combustion gas generated at this time. Is cooled.

In the fuel cell 6, an electrochemical reaction takes place.
Heat is generated by activation overvoltage, concentration overvoltage, and resistance overvoltage during the electrochemical reaction.

Between the above-mentioned reformer 3 and the CO shift converter 4, CO
Between the transformer 4 and the CO remover 5, the CO remover 5 and the fuel cell 6
Heat exchangers 18, 19, 20, and 27 are connected to the space and the exhaust system 26 of the fuel cell 6, respectively.

Then, the water in the water tank 21 circulates through the heat exchangers 18, 19, 20 via pumps 23, 24, 25, and the reformer 3, the CO converter 4, CO
The gas passing through the remover 5 is cooled. Heat exchanger 2
7 is supplied with water from the hot water storage tank 112 (FIG. 2).
Circulate through 8.

The cooling section 6c of the fuel cell 6 includes a pump 48
The water in the water tank 21 circulates through the, and the water cools the fuel cell 6.

A heat exchanger 17 is connected to the exhaust system 31 of the reformer 3. When the water in the water tank 21 is supplied via a pump 22, the water is turned into steam in the heat exchanger 17. Steam is mixed with the raw fuel and supplied to the reformer 3.

In addition to the heat exchanger 17, another heat exchanger 32 is connected to the exhaust system 31, and the water in the hot water storage tank 112 is supplied to the heat exchanger 32 via a pump 33. Circulates to recover waste heat.

The present system includes a process gas (PG) burner 34.

At the start of the system, the reformer 3, CO
Since the reformed gas that has passed through the transformer 4 and the CO remover 5 is not stable, the reformed gas is transferred to the fuel cell 6 until it becomes stable.
Can not be supplied. Therefore, the gas in an unstable state is guided to the PG burner 34 and burned until each reactor is stabilized. Then, after each reactor is stabilized, it is introduced into the fuel cell 6 to generate power. Unreacted gas that could not be used for power generation in the fuel cell 6 is first guided to the PG burner 34 and burned. After the system of the present system is stabilized, it is introduced into the burner 12 of the reformer 3 and burned.

The control system of the PG burner 34 will be described. After the start of the present system, the on-off valve 91 is closed until the temperature of each reactor is stabilized, and the reformed gas passes through the pipe 35 and the on-off valve 36. Through the PG burner 34. When the temperature of each reactor is stabilized, the on-off valve 91 is opened and the on-off valve 92 is opened until the temperature of the fuel cell 6 is stabilized.
Is closed, the reformed gas is supplied to the PG burner 34 through the pipe 38 and the on-off valve 39, and is burned there.
When the temperature of the fuel cell 6 is stabilized and power is continuously generated, the open / close valves 91 and 92 are opened, the open / close valves 36 and 39 are closed, and the unreacted gas that has passed through the fuel cell 6 passes through the pipe 15. After that, it is supplied to the burner 12.

A heat exchanger 46 is connected to an exhaust system 45 of the PG burner 34, and a pump 47 is connected to the heat exchanger 46.
Circulates through the hot water storage tank 112.

Between the water tank 21 and the hot water storage tank 112,
The heat exchanger 41 is connected, and the water in the water tank 21 circulates through the heat exchanger 41 via a pump 42 and a pump 43
The water in the hot water storage tank 112 circulates through the.

By the heat exchange in the heat exchanger 41, the temperature of the water in the hot water storage tank 112 increases, and the temperature of the water in the water tank 21 decreases.

In the above configuration, since the small household power supply system S takes the form of a cogeneration system, effective use of energy is achieved.

Accordingly, a high overall thermal efficiency can be obtained,
Raw fuel consumption is reduced and carbon dioxide emissions are reduced.

FIG. 4 shows the structure of the reformer 3.

The reformer 3 is provided with a burner 12 at a lower portion via a heat insulating material 300. The burner 12 has a burner head 301 and a bar case 302 in which the burner head 301 is housed.
Is supplied with a mixture of fuel and air as described above. That is, the burner head 301 has the pipe 13
Raw fuel (high calorie gas) is supplied via (FIG. 3), air is supplied via fan 14 (FIG. 3), and unreacted hydrogen (A) is passed through anode 6a via pipe 15 (FIG. 3). Low calorie gas) is supplied.

The combustion gas of this burner 12 is
The fuel gas is introduced into the reformer main body 304 through a combustion tube 303 penetrating through zero.

The reformer main body 304 is formed on the outer periphery of the combustion tube 303 inside the reformer main body 304 and communicates with the combustion tube 303 on the tip 303A side of the combustion tube 303. First passage 305 of the burning combustion gas
And a raw fuel passage 307 formed on an outer peripheral portion of the first passage 305 and having a catalyst layer 306 for reforming the supplied raw fuel, and a combustion gas formed on the outer peripheral portion of the raw fuel passage 307. A second passage 308 and a third passage 309 communicating the second passage 308 and the first passage 305 on the rear end 303B side of the combustion tube 303 are provided.

The upper part of the reformer main body 304 has a heat exchanger 3
15 are arranged. The heat exchanger 315 is configured by alternately spirally winding a pipe 316 for leading the raw fuel to the catalyst layer 306 and a pipe 317 for leading the reformed gas reformed by the catalyst layer 306. The combustion exhaust gas passing through the second passage 308 rises in the space 315A in which the heat exchanger 315 is disposed, and the heat of the exhaust gas heats the raw fuel passing through the pipe 316. Then, the exhaust gas is exhausted through the exhaust port 318.

FIGS. 5A and 5B show the structure of the burner 12. FIG.

In this embodiment, a cylindrical burner head 301 is incorporated concentrically into a cylindrical burner case 302, and an annular cooling air passage 320 is provided between the burner case 302 and the burner head 301. Is formed. 320A is a support plate, and a small hole 320B is formed in the support plate 320A. On an outer peripheral wall 301A of the burner head 301, a plurality of flame holes 321 formed of vertically elongated slits are formed at substantially equal intervals in a circumferential direction.
A combustion chamber 3 for forming a flame is provided inside the outer peripheral wall 301A.
23 are formed. In addition, 322 is a diffusion plate.

On the bottom plate 301B of the burner head 301,
The fuel supply pipe 324 having a double pipe structure is connected to the inner pipe 324A (second pipe) of the fuel supply pipe 324 having the double pipe structure.
The unreacted hydrogen (low-calorie gas) that has passed through the anode 6a is supplied via a pipe 15 (FIG. 3) to the outer pipe 324B (first inlet pipe).
Raw fuel (high-calorie gas) is supplied via a fuel cell 3 (FIG. 3). Inside the burner case 302, the fan 14 (FIG. 3)
The air is supplied via.

In this embodiment, a cylindrical burner head 301 is provided with a cooling air passage 320 around it, and a plurality of vertically elongated flames are provided on an outer peripheral wall 301A of the burner head 301 facing the cooling air passage 320. Since the holes 321 are formed at substantially equal intervals in the circumferential direction, a sufficient amount of primary air is supplied through each of the flame holes 321. Therefore, in this burner head 301, the inner pipe 324 of the fuel supply pipe 324
A anode 6a introduced through A (second introduction pipe)
Even if it is unreacted hydrogen (low-calorie gas) that has passed through, or raw fuel (high-calorie gas) introduced through its outer pipe 324B (first inlet pipe), these gases having different calories are removed. Combustion can be performed selectively or premixed using a common flame hole 321.

In this embodiment, when burning low-calorie gas and / or high-calorie gas, a flame is formed inside the burner head 301, and a cooling air passage 320 is formed outside the burner head 301. Therefore, the outer wall of the burner case 302 does not become hot due to the combustion.

Since the flame hole for burning the high calorie gas and the flame hole for burning the low calorie gas are common, there is no need to form two types of flame holes as in the prior art.

Since there is no need for a premixing chamber for burning high calorie gas, it is possible to prevent the occurrence of flashback toward the premixing chamber.

Next, the operation of the reformer will be described.

The chemical reaction through the catalyst layer 306 of the reformer 3 is an endothermic reaction. Therefore, the combustion gas of the burner 12 is always supplied.

Under this heating, the raw fuel passing through the pipe 316 enters the raw fuel passage 307 having the catalyst layer 306. The raw fuel passage 307 includes an inner passage 307A having a catalyst layer 306 and a catalyst layer 306 located outside the inner passage 307A.
And the outer passage 307B which does not have the same. The catalyst layer 306 is always heated to 700 to 800 ° C. When a mixture of steam and raw fuel is supplied to the catalyst layer 306 as described above, the mixture is A reforming reaction is performed to convert the gas into a reformed gas containing hydrogen, carbon dioxide, and carbon monoxide.

The reformed gas is supplied to the rear end 3 of the catalyst layer 306.
06B, the catalyst layer 30 from the inner passage 307A.
6. Enter the outer passage 307B that does not have a 6. Then, it rises inside the outer passage 307B, and is led to the next step (CO converter 4) through a pipe 317 constituting the heat exchanger 315.

The combustion gas of the burner 12 is introduced through the combustion tube 303, enters the first passage 305 on the tip 303 A side of the combustion tube 303, descends there, and forms the third passage 309 at the lower end of the first passage 305. Enter the second passage 308 via
It rises in the second passage 308 and enters the space 315 </ b> A where the heat exchanger 315 is arranged, where it gives heat to the raw fuel passing through the pipe 316, and then is exhausted through the exhaust port 318.

Although the present invention has been described based on one embodiment, it is clear that the present invention is not limited to this. For example, the plurality of flame holes 321 are not limited to vertically long slits, and may be a large number of circular holes.

[0059]

According to the present invention, there is provided a burner head having a flame hole on the outer peripheral wall and a combustion chamber inside thereof, a first inlet pipe for introducing high-calorie gas into the combustion chamber of the burner head,
The second to introduce low calorie gas into the combustion chamber of this burner head
With an introduction pipe, the gas having different calories was configured to be selectively or premixed using a common flame hole and burnable, so that it is not necessary to form two types of flame holes as in the related art, Moreover, since a premixing chamber for burning high-calorie gas is not required, it is possible to prevent the occurrence of flashback toward the premixing chamber.

[Brief description of the drawings]

FIG. 1 is a system diagram when a polymer electrolyte fuel cell power generation system according to the present invention is installed at home.

FIG. 2 is a view showing an outdoor part of FIG. 1;

FIG. 3 is a circuit diagram showing one embodiment of a polymer electrolyte fuel cell power generation system.

FIG. 4 is a sectional view showing a structure of a reformer.

FIG. 5A is a cross-sectional view showing a burner structure, and FIG. 5B is a plan view.

FIG. 6 is a sectional view showing a structure of a conventional burner.

[Explanation of symbols]

 Reference Signs List 3 reformer 4 CO converter 5 CO remover 6 fuel cell 12 burner 301 burner head 302 bar case 320 cooling air passage 321 flame hole 323 combustion chamber 324 fuel supply pipe 324A inner pipe (second inlet pipe) 324B outer Pipe (first introduction pipe)

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Keigo Miyai 2-5-5 Keihanhondori, Moriguchi-shi, Osaka F-term in Sanyo Electric Co., Ltd. (reference) 3K017 AA04 AA05 AB01 AC01 AD12 AE02 3K065 RA01 RB01 4G040 EA02 EA03 EA06 EB04 EB14 EB33 5H026 AA06 5H027 AA06 BA01 BA17

Claims (5)

[Claims] 1. A burner head having a flame hole in an outer peripheral wall and a combustion chamber inside thereof, a first inlet pipe for introducing high-calorie gas into a combustion chamber of the burner head, and a burner head of the burner head. A second introduction pipe for introducing low-calorie gas into the combustion chamber, wherein the gas having different calories is selectively or premixed by using a common flame hole so as to be combustible. 2. The combustion apparatus according to claim 1, wherein the burner head is concentrically incorporated in the burner case, and an annular cooling air passage is formed between the burner case and the burner head. 3. The combustion apparatus according to claim 1, wherein the flame holes are vertically elongated slits or circular holes. 4. A reformer for reforming hydrogen by chemically reacting a fuel gas such as natural gas or city gas in a state of being constantly heated by a combustion device, wherein the combustion device has a flame hole in an outer peripheral wall. A burner head having a combustion chamber therein, a first inlet pipe for introducing a high-calorie gas into the combustion chamber of the burner head, and a second inlet pipe for introducing a low-calorie gas to the combustion chamber of the burner head A reformer, comprising: a tube; and a combustor configured to selectively or premix the gases having different calories using a common flame hole. 5. A reformer for reforming hydrogen into hydrogen by chemically reacting a fuel gas such as natural gas or city gas while constantly heating with a combustion device, a CO converter for converting carbon monoxide, In a polymer electrolyte fuel cell power generation system comprising a CO remover for removing carbon oxide and a fuel cell for generating electricity using hydrogen, the combustion device has a flame hole on an outer peripheral wall, and a combustion hole is provided inside the flame hole. A burner head having a chamber, a first inlet pipe for introducing the high-calorie fuel gas to the combustion chamber of the burner head, and a low-calorie unreacted gas returned from the fuel cell to the combustion chamber of the burner head. And a second introduction pipe for guiding the gas, wherein the gases having different calories are selectively or premixed by using a common flame hole and are configured to be combustible. system.