JPH10302824A - Carbon monoxide removing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a carbon monoxide removing device capable of always maximally performing a CO oxidizing function. SOLUTION: The device has a catalyst for oxidizing carbon monoxide on the inside and a reactor 11 which oxidizes carbon monoxide in reformed gas 2 flowing through the inside to remove it. A cooling pipe 12 is arranged on the inside of the reactor 11, and one end of the cooling pipe 12 is connected to a cooling water tank 13 for storing cooling water 6 through a circulation pump 14. The other end of the cooling pipe 12 is connected to the cooling water tank 13 through a radiator 15, and by the operation of the circulation pump 14, the cooling water 6 in the cooling water tank 13 is passed through the cooling pipe 12, then cooled to a given temperature range, and returned again to the cooling water tank 15. Heat generated by the selective oxidation reaction of CO in the reformed gas 2 attendant on passing through the reactor 1 is absorbed, and temperature rising in the reactor 1 is inhibited.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for removing carbon monoxide, and more particularly to a device for supplying a hydrocarbon-based fuel reforming gas as a fuel hydrogen gas to a polymer electrolyte fuel cell. It is valid.

[0002]

[Prior art]

(1) Principle of Power Generation of Solid Polymer Electrolyte Fuel Cell A solid polymer electrolyte fuel cell is a solid polymer ion exchange membrane (for example, a fluorine resin ion exchange membrane having a sulfonic acid group) as shown in FIG. An electrode assembly 206 structure is provided in which catalyst electrodes 202 and 203 (for example, platinum) layers and porous carbon electrodes 204 and 205 are provided on both sides of an electrolyte 201 that uses.

In such a solid polymer electrolyte fuel cell, the humidified fuel hydrogen gas supplied to the anode electrode is hydrogen-ionized on the catalyst electrode (anode electrode) 202, and the hydrogen ions pass through the electrolyte 201. Under the presence of water, the electrons move to the cathode side together with water in the form of H ⁺ .xH ₂ O, and the oxygen in the oxidant gas and the electrons flowing through the external circuit 207 on the catalyst electrode (cathode electrode) 203. Reacts with to produce water. This generated water is supplied to the cathode 20
From 3,205, it is conveyed to the residual oxidant gas and discharged out of the fuel cell. At this time, the electron flow flowing through the external circuit 207 can be used as DC electric energy.

[0004] In the above-mentioned electrolyte 201 using a solid polymer ion exchange membrane, it is necessary to always keep the electrolyte 201 in a sufficiently wet state in order to exhibit hydrogen ion permeability. For this reason, usually, the fuel hydrogen gas or the oxidizing gas contains saturated steam corresponding to the vicinity of the operating temperature (normal temperature to about 100 ° C.) of the battery, that is, the fuel hydrogen gas or the oxidizing gas is humidified, and Is supplied to the electrode assembly 106 to maintain the electrolyte 101 in a wet state.

(2) Characteristics of solid polymer electrolyte fuel cell The fuel hydrogen gas supplied to the solid polymer electrolyte fuel cell includes pure hydrogen gas and hydrocarbon fuel reformed by reforming methanol or methane. Gas and the like. this house,
Hydrocarbon-based fuel reforming gas and the like are usually carbon monoxide (C
O) is contained in a large amount (about 0.1% to several%), so that direct supply to a solid polymer electrolyte fuel cell causes a problem.

Specifically, an example of the relationship between the CO concentration in the fuel hydrogen gas supplied to the solid polymer electrolyte fuel cell and the power generation characteristics of the solid polymer electrolyte fuel cell (current density-single cell voltage characteristics) As shown in FIG. 10, the power generation characteristics of the solid polymer electrolyte fuel cell deteriorate as the CO concentration in the fuel hydrogen gas supplied to the polymer electrolyte fuel cell increases to 20 ppm, 50 ppm, and 100 ppm. It will be lost.

The reason is that the fuel hydrogen gas supplied is CO
Contains platinum, which is a catalyst component of the anode
It is adsorbed and poisoned by O, causing a decrease in the activation function,
This is considered to cause a decrease in the ionization function of hydrogen as described above. Therefore, when a fuel hydrogen gas containing a large amount of CO, such as a hydrocarbon-based fuel reforming gas, is supplied to a solid polymer electrolyte fuel cell, the CO in the gas is reduced to a concentration as low as possible. The gas needs to be supplied afterwards.

(3) Conventional Fuel Hydrogen Gas Supply System to Solid Polymer Electrolyte Fuel Cell A solid polymer electrolyte fuel cell uses a gas obtained by reforming methanol, which is one of hydrocarbon fuels, as fuel hydrogen gas. FIG. 8 shows a schematic configuration of an example of a conventional supply system when supplying.

As shown in FIG. 8, methanol water 1 in which methanol and water are mixed at a predetermined ratio is evaporated in an evaporator 101, and the methanol water 1 is evaporated in a reformer 102 filled with a reforming catalyst (for example, copper). Reform (around 250-300 ° C). The reforming reaction at this time is represented by the following equation (1), and CO is generated as a by-product in the reaction process.

[0010]

Embedded image CH ₃ OH + H ₂ O → 3H ₂ + CO ₂ (Endothermic reaction) (1)

The reformed gas 2 generated in the reformer 102 is CO
The CO is introduced into a CO converter 103 filled with a shift catalyst (for example, a copper-zinc system), and the CO concentration is reduced (generally, 0.1%).
vol.% to around 2-3 vol.%). C at this time
The O shift reaction is represented by the following equation (2).

[0012]

[Image Omitted] CO + H ₂ O → H ₂ + CO ₂ (exothermic reaction) (2)

The reformed gas 2 whose CO concentration has been reduced by the CO converter 103 is supplied to a reactor 111 of a carbon monoxide removing device 110 filled with a selective oxidation catalyst (for example, a noble metal) for selectively oxidizing CO. The CO concentration is further reduced (about 100 ppm, preferably 20 ppm or less is desirable). The selective oxidation reaction at this time is represented by the following equation (3).

[0014]

Embedded image CO + 1 / 2O ₂ → CO ₂ (exothermic reaction) (3)

In this selective oxidation reaction, since oxygen is required as an oxidizing agent, the carbon monoxide removing device 11
A predetermined amount of air (oxygen) 3 is introduced into the reformed gas before being introduced into the 0 reactor 111. The catalyst may partially oxidize hydrogen (H ₂ ) in the reformed gas 2 in some cases, but the amount is extremely small, so that no particular problem occurs.

The reformed gas 2 whose CO concentration has been further reduced by the carbon monoxide removing device 110 is humidified by the humidifier 104, and is then supplied to the anode 107 a of the solid polymer electrolyte fuel cell 107 as fuel hydrogen gas. After being supplied and reacting with oxygen in the oxidizing gas 4 supplied to the cathode 107b as described above, the oxygen is supplied to the power generation, and then sent out of the system as the remaining fuel hydrogen gas 2a. 4
Is sent out of the system as a residual oxidant gas 4a.

In FIG. 8, reference numeral 105 denotes a humidifier for humidifying the oxidizing gas 4, and reference numeral 106 denotes a solid polymer electrolyte fuel cell 1.
07 is maintained at a predetermined temperature with cooling water 5.
06a is a pump, and 108 is an external electric output.

[0018]

Here, in the carbon monoxide removing apparatus 110 as described above, the catalyst temperature (the temperature of the reformed gas which becomes the catalyst atmosphere) when a Ru system is used as the selective oxidation catalyst for CO. 11) shows an example of the relationship between the CO concentration of the reformed gas in the vicinity of the outlet after passing through the catalyst, and FIG.
An example of the relationship between the catalyst temperature (the temperature of the reformed gas serving as the catalyst atmosphere) when a Pt-based catalyst is used as the CO selective oxidation catalyst and the CO concentration of the reformed gas in the vicinity of the outlet port passing through the catalyst will be described. As shown in FIG.

As can be seen from FIGS. 11 and 12, since the selective oxidation catalyst has an optimum temperature range in which the oxidation function is efficiently exhibited, the temperature of the atmosphere is adjusted so that the selective oxidation catalyst has the above-mentioned optimum temperature range. That is, it is necessary to adjust the temperature of the reformed gas 2.

However, the reformed gas 2 contains about 1 vol.
If it is contained, the temperature of the reformed gas 2 is increased by about 90 ° C. at the outlet and the outlet of the carbon monoxide removal reactor 111 due to the heat generated by the oxidation reaction. If the gas 2 contains 0.1 vol.% Of CO, the reformed gas 2 rises by about 9 ° C. Even if the temperature of the reformed gas 2 to be introduced is adjusted, the temperature of the reformed gas 2 increases as approaching the outlet of the reactor 111 of the carbon monoxide removing device 110, and the selective oxidation catalyst is moved to the optimum temperature. It will be difficult to keep it in the area.

For this reason, C of the carbon monoxide removing device 110
The O-oxidation function is reduced, and the catalyst component of the anode 107a of the solid polymer electrolyte fuel cell 107 (for example,
As described above, there is a possibility that platinum (platinum) is adsorbed and poisoned by CO to cause a decrease in the activation function.

In view of the above, an object of the present invention is to provide a carbon monoxide removing apparatus which can always exert the CO oxidizing function to the maximum.

[0023]

In order to solve the above-mentioned problems, a carbon monoxide removing apparatus according to the present invention is provided with a catalyst for oxidizing carbon monoxide therein, and comprises a catalyst for oxidizing carbon monoxide in a gas flowing therethrough. In a carbon monoxide removing apparatus comprising a reactor for oxidizing and removing carbon, a temperature holding means for holding the gas flowing inside the reactor within a predetermined temperature range is provided. .

In the above-mentioned carbon monoxide removing apparatus, the temperature holding means is a refrigerant circulation means disposed inside the reactor and cooling the gas with a refrigerant.

The above-mentioned carbon monoxide removing apparatus is characterized in that the reactor is divided into a plurality of parts, and the temperature holding means is arranged between the reactors to cool the gas with a refrigerant.

The above-mentioned carbon monoxide removing apparatus is characterized in that the reactor is divided into a plurality of parts, and the temperature holding means are respectively arranged on the outer surfaces of the reactor, and the gas is cooled by a refrigerant.

In the above-mentioned carbon monoxide removing apparatus, the temperature holding means includes a refrigerant flow rate adjusting means for adjusting the flow rate of the refrigerant based on the temperature of the gas flowing through the reactor or the concentration of carbon monoxide. It is characterized by being.

In the above carbon monoxide removing apparatus, the refrigerant is humidified water for humidifying a fuel hydrogen gas or an oxidizing gas supplied to a fuel cell.

In the above-described carbon monoxide removing apparatus, the refrigerant is cooling water for cooling a fuel cell.

In the above-mentioned carbon monoxide removing apparatus, the refrigerant is air used as an oxidizing gas supplied to a fuel cell.

[0031]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a first embodiment in which a carbon monoxide removing apparatus according to the present invention is applied to a system for supplying fuel hydrogen gas to a solid polymer electrolyte fuel cell.
This will be described with reference to FIG. FIG. 1 is a schematic configuration diagram.

As shown in FIG. 1, the outlet of an evaporator 101 for evaporating methanol water 1 in which methanol and water are mixed at a predetermined ratio is filled with a reforming catalyst (for example, copper-based). It is connected to a receiving port of the reformer 102. The outlet of the reformer 102 is provided with a CO shift catalyst (for example, a CO shift catalyst for reducing the CO concentration of the reformed gas 2 from the reformer 102).
(Copper-zinc system) is connected to the inlet of the CO transformer 103 filled therein. The outlet of the CO transformer 103 is
A selective oxidation catalyst (e.g., a noble metal-based catalyst) for selectively oxidizing CO is connected to a receiving port of a reactor 11 of a carbon monoxide removing device 10 filled therein.

A cooling pipe 12 is provided inside the reactor 11. The cooling pipe 12 has one end connected to a cooling water tank 13 that stores the cooling water 6 as a refrigerant via a circulation pump 14, and the other end connected to the cooling water tank 1.
3 is connected via a radiator 15. That is, the cooling water 6 in the cooling water tank 13 is circulated through the cooling pipe 12 by the operation of the circulation pump 14, then cooled by the radiator 15 within a predetermined temperature range, and then re-enters the cooling water tank 13. It is to be returned. Such a cooling pipe 12, a cooling water tank 13, a circulation pump 14, a radiator 1
5 and the like constitute a temperature holding means in the present embodiment.

The reactor 11 of the carbon monoxide removing device 10
Is connected to the receiving port of the humidifier 104.
The outlet of the humidifier 104 is connected to the anode 107 a of the polymer electrolyte fuel cell 107. On the other hand, the cathode 1 of the polymer electrolyte fuel cell 107
A humidifier 105 for humidifying the oxidizing gas 4 is provided in a portion 07b.
Outlets are connected. In FIG. 1, reference numeral 106 denotes a cooling line for flowing the cooling water 5 through the fuel cell 107;
106a is a cooling water pump, and 108 is an external electric output.

In the fuel hydrogen gas supply system thus configured, the methanol water 1 is evaporated in the evaporator 101 and reformed in the reformer 102 (about 250 to 300 ° C.).
Then, the reformed gas 2 is introduced into the CO converter 103 to reduce the CO concentration (generally from about 0.1 vol.% To about 2 to 3 vol.%), And then the carbon monoxide removing device together with the air (oxygen) 3. When introduced into the reactor 11, the cooling water 6 flowing through the cooling pipe 12 absorbs the heat generated by the progress of the selective oxidation reaction of CO in the reformed gas 2, and the temperature rise in the reactor 11 is suppressed. You. For this reason, the temperature of the selective oxidation catalyst can be maintained in the optimum temperature region where the selective oxidation function can be exhibited most efficiently, so that the CO concentration in the reformed gas 2 can be further reduced efficiently.

The reformed gas 2 whose CO concentration has been further reduced efficiently by the carbon monoxide removing device 10 is humidified by a humidifier 104 and then converted into a fuel hydrogen gas as an anode 107 a of a solid polymer electrolyte fuel cell 107. And the anode 107 a of the solid polymer electrolyte fuel cell 107.
The oxidizing gas 4 supplied to the cathode 107b without causing the activation function of the catalyst component to decrease.
After reacting with oxygen in the above-described manner and being supplied to power generation, it is sent out of the system as a residual fuel hydrogen gas 2a, while the oxidizing gas 4 is sent out of the system as a residual oxidizing gas 4a. . Therefore, the solid polymer electrolyte fuel cell 1
In No. 07, a decrease in power generation characteristics is suppressed, and power can be stably generated.

Therefore, according to the carbon monoxide removing device 10 as described above, the temperature of the selective oxidation catalyst can be maintained in the optimum temperature range in which the selective oxidation function can be exhibited most efficiently. This can be maximized, and a decrease in the power generation characteristics of the polymer electrolyte fuel cell 107 can be suppressed.

A second embodiment in which the apparatus for removing carbon monoxide according to the present invention is applied to a system for supplying fuel hydrogen gas to a polymer electrolyte fuel cell will be described with reference to FIG. FIG. 2 is a schematic configuration diagram thereof. However, the same parts as those in the above-described first embodiment are denoted by the same reference numerals as those in the above-described first embodiment, and description thereof will be omitted.

As shown in FIG. 2, the carbon monoxide removing device 2
One end of the cooling pipe 12 disposed inside the reactor 11 is connected to the humidifier 105 and the other end is connected to the circulation pump 14.
And a part of the humidifying water for humidifying the oxidizing gas 4 through a cooling pipe 12.
It can be returned again after it has been distributed inside.

That is, the humidifying water for humidifying the oxidizing gas 4 is used as the refrigerant.

For this reason, as in the case of the first embodiment described above, the temperature of the selective oxidation catalyst is maintained in the optimum temperature range in which the selective oxidation function can be exhibited most efficiently, and Not only can the CO concentration be efficiently reduced further, but also the amount of heating energy of the oxidizing gas 4 in the humidifier 105 can be reduced.

Therefore, it is possible to obtain the same effect as that of the first embodiment described above, as well as to improve the efficiency of heat energy.

Although the radiator 15 is used in this embodiment, the radiator 15 can be omitted as long as the humidifying water can be maintained within a predetermined temperature range. Also,
In the present embodiment, the humidifying water for humidifying the oxidizing gas 4 is used as the refrigerant, but the humidifier 1 for humidifying the fuel hydrogen gas 2 is used.
04 humidified water may be used as the refrigerant.

A third embodiment in which the carbon monoxide removing device according to the present invention is applied to a system for supplying fuel hydrogen gas to a polymer electrolyte fuel cell will be described with reference to FIG. FIG. 3 is a schematic configuration diagram thereof. However, for the same parts as those in the above-described embodiments, the same reference numerals as those in the above-described embodiments are used.
The description is omitted.

As shown in FIG. 3, a valve 31 is provided in a part of a cooling line 106 through which the cooling water 5 after cooling the solid polymer electrolyte fuel cell 107 flows. The cooling pipe 12 disposed inside the reactor 11 of the carbon monoxide removing device 30 has one end connected to the cooling line 106 upstream of the valve 31 via a valve 32, and the other end connected to the cooling line 106. Is connected to the downstream side of the valve 31 and a part or all of the cooling water 5 is supplied to the cooling line 106.
After flowing through the cooling pipe 12, the cooling line 106 can be returned to the cooling line 106 again.

That is, the solid polymer electrolyte fuel cell 10
The cooling water 5 obtained by cooling the cooling water 7 is used as a refrigerant.

Therefore, as in the case of the first embodiment described above, the temperature of the selective oxidation catalyst is maintained in the optimum temperature range where the selective oxidation function can be exhibited most efficiently, and Not only can the CO concentration be efficiently reduced further, but also various members such as a cooling water pump 106a for cooling the fuel cell 107 and a radiator (not shown) can be used as temperature holding means.

Therefore, it is possible to obtain the same effect as that of the first embodiment described above, as well as to reduce the number of members and suppress an increase in cost.

A fourth embodiment in which the carbon monoxide removing apparatus according to the present invention is applied to a system for supplying fuel hydrogen gas to a solid polymer electrolyte fuel cell will be described with reference to FIG. FIG. 4 is a schematic configuration diagram thereof. However, for the same parts as those in the above-described embodiments, the same reference numerals as those in the above-described embodiments are used.
The description is omitted.

As shown in FIG. 4, a flow control valve 41 is provided in the cooling line 106 through which the cooling water 5 after cooling the solid polymer electrolyte fuel cell 107 flows. One end of the cooling pipe 12 disposed inside the reactor 11 of the carbon monoxide removing device 40 is connected to the upstream side of the flow control valve 41 of the cooling line 106 via the flow control valve 42, Is the flow control valve 41 of the cooling line 106.
Is connected downstream. Between the carbon monoxide removing device 40 and the humidifier 104, the carbon monoxide removing device 40
Temperature sensor 43 that measures the temperature of reformed gas 2 that has passed
Is provided. The temperature sensor 43 is electrically connected to an input section of the control device 44, and the flow control valves 41 and 42 are
The control unit 44 is electrically connected to an output unit of the control unit 44, and can control the flow control valves 42 and 43 based on a signal from the temperature sensor 43. In the present embodiment, the flow rate control valves 41 and 42, the temperature sensor 43, the control device 44, and the like constitute a refrigerant flow rate adjusting unit.

In such a carbon monoxide removing device 40,
When the reformed gas 2 flowing through the reactor 11 exceeds a predetermined temperature range, the control device 44 increases the flow rate of the cooling water 5 flowing through the cooling pipe 12 based on a signal from the temperature sensor 43. Controls the flow control valves 41, 42, while
If the reformed gas 2 flowing through the reactor 11 does not reach the predetermined temperature range, the control device reduces the flow rate of the cooling water 5 flowing through the cooling pipe 12 based on a signal from the temperature sensor 43. 44 controls the flow control valves 41 and 42. Thereby, the reformed gas 2 flowing in the reactor 11 is always kept constant within a predetermined temperature range.

Therefore, the temperature of the selective oxidation catalyst can be more reliably maintained in the optimum temperature region where the selective oxidation function can be exhibited most efficiently than in the above-described embodiment, and therefore, it is possible to maintain the temperature of the selective oxidation catalyst more than in the above-described embodiment. Can more reliably exhibit the CO oxidation function, and can more reliably suppress a decrease in the power generation characteristics of the polymer electrolyte fuel cell 107.

In the present embodiment, the temperature sensor 43 is provided between the carbon monoxide removing device 40 and the humidifier 104. However, the temperature sensor 43 is provided in the outlet port of the reactor 11 or inside. Is also good.

In the present embodiment, the temperature sensor 43
Although the flow rate of the cooling water 5 is adjusted based on the signal from the above, instead of the temperature sensor 43, a CO concentration detection sensor for detecting the CO concentration of the reformed gas 2 flowing through the reactor 11 is provided. When the CO concentration of the reformed gas 2 flowing through the cooler 11 exceeds a predetermined value, the flow rate is controlled so as to increase the flow rate of the cooling water 5 flowing through the cooling pipe 12 based on a signal from the sensor. While controlling the valves 41 and 42, when the CO concentration of the reformed gas 2 flowing through the inside of the reactor 11 becomes equal to or less than a predetermined value, based on a signal from the sensor,
By controlling the flow control valves 41 and 42 so that the cooling water 5 flowing through the cooling pipe 12 has a predetermined flow rate,
It is also possible to always keep the reformed gas 2 flowing in the reactor 11 constant within a predetermined temperature range.

A fifth embodiment in which the carbon monoxide removing device according to the present invention is applied to a system for supplying fuel hydrogen gas to a solid polymer electrolyte fuel cell will be described with reference to FIG. FIG. 5 is a schematic configuration diagram thereof. However, for the same parts as those in the above-described embodiments, the same reference numerals as those in the above-described embodiments are used.
The description is omitted.

As shown in FIG. 5, the outlet of the CO converter 103 is connected to the inlet of the first reactor 51a filled with a selective oxidation catalyst (for example, a noble metal) for selectively oxidizing CO. Are linked. The outlet of the first reactor 51a is connected to the inlet of a gas radiator 52, which is an air-cooled temperature maintaining means using air as a refrigerant. Gas radiator 52
Is connected to the receiving port of the second reactor 51b having the same structure as the first reactor 51a. The outlet of the second reactor 51b is connected to the inlet of the humidifier 104.

That is, the reactor 1 of each embodiment described above.
The first selective oxidation reaction function is divided into a plurality of first reactors 51a and a plurality of second reactors 51b (divided into two).
The gas radiator 52 is provided between a and 51b.

For this reason, the reformed gas 2 can be cooled by the gas radiator 52 having a simpler structure than in the above-described embodiments.

Therefore, according to such a carbon monoxide removing device 50, the same effects as those of the first embodiment can be obtained, and in each of the above-described embodiments. A simpler configuration can be achieved.

In the present embodiment, the air-cooled gas radiator 52 is used, but a water-cooled gas cooler using water as a refrigerant may be used.

A sixth embodiment in which the apparatus for removing carbon monoxide according to the present invention is applied to a system for supplying fuel hydrogen gas to a polymer electrolyte fuel cell will be described with reference to FIG. FIG. 6 is a schematic configuration diagram thereof. However, for the same parts as those in the above-described embodiments, the same reference numerals as those in the above-described embodiments are used.
The description is omitted.

As shown in FIG. 6, an air heat exchanger 61 is provided between the first reactor 51a and the second reactor 51b. An air compressor 62 is connected to an air receiving port of the air heat exchanger 61. An air outlet of the air heat exchanger 61 is connected to a humidifier 105 for humidifying the oxidizing gas 4.

That is, in this embodiment, the temperature maintaining means is constituted by the air heat exchanger 61, the air compressor 62 and the like, and the air used as the refrigerant is used as the oxidizing gas 4.

Therefore, similarly to the fifth embodiment described above, the reformed gas 2 can be cooled by the temperature holding means having a simple structure, and in the case of the second embodiment described above. Similarly to the above, the amount of energy required for heating the oxidizing gas 4 can be reduced.

Therefore, according to such a carbon monoxide removing device 60, it is possible to obtain both the effects obtained in the second embodiment and the fifth embodiment described above.

A seventh embodiment in which the carbon monoxide removing device according to the present invention is applied to a system for supplying fuel hydrogen gas to a polymer electrolyte fuel cell will be described with reference to FIG. FIG. 7 is a schematic configuration diagram thereof. However, for the same parts as those in the above-described embodiments, the same reference numerals as those in the above-described embodiments are used.
The description is omitted.

As shown in FIG. 7, on the outer surfaces of the first reactor 51a and the second reactor 51b, a plurality of radiating fins 71a and 71b as temperature holding means are provided upright.

That is, by using the radiation fins 71a and 71b in place of the gas radiator 52 and the air heat exchanger 61 of the fifth and sixth embodiments, the modified gas 2
The heat energy of the reactor 51a, 5
The reformed gas 2 is discharged outside the system via 1b, that is, the reformed gas 2 is cooled.

Therefore, the reformed gas 2 can be cooled with a simpler structure than in the fifth and sixth embodiments.

Therefore, according to the carbon monoxide removing device 70, it is possible to obtain the same effect as that of the first embodiment described above.
The configuration can be simpler than that of the fifth and sixth embodiments.

A forced cooling fan that blows air toward the reactors 51a and 51b is provided.
It is also possible to provide a refrigerant flow rate adjusting means for controlling the forced cooling fan so as to adjust the amount of heat radiated from the radiating fins 71a and 71b based on the temperature and the CO concentration of the reformed gas 2 flowing through the cooling gas. It is.

Further, instead of the radiation fins 71a and 71b, cooling tubes through which cooling water flows are connected to the reactors 51a and 51b.
It is also possible to provide on the outer surface of b, that is, to use a water-cooled type.

In the fifth to seventh embodiments described above,
Although the selective reactor function of the integrated reactor 11 is divided into two parts in series, the first reactor 51a and the second reactor 51b are used, but they may be divided into three or more parts in series or in parallel.

[0074]

According to the carbon monoxide removing apparatus of the present invention,
A catalyst for oxidizing carbon monoxide is provided inside, and in a carbon monoxide removing device comprising a reactor for oxidizing and removing carbon monoxide in a gas flowing through the inside, the inside of the reactor is circulated. Since the temperature holding means for holding the gas within a predetermined temperature range is provided, the temperature of the catalyst can be held in the optimum temperature range where the selective oxidation function can be exhibited most efficiently, so that the CO oxidation function is always maximized. Can be demonstrated to the maximum extent. For this reason, if the carbon monoxide removal device is applied to a system for supplying fuel hydrogen gas to a polymer electrolyte fuel cell, it is possible to prevent a decrease in the activation function of the catalyst component of the anode electrode of the fuel cell. It is possible to suppress a decrease in power generation characteristics.

Further, if the temperature maintaining means is disposed inside the reactor and the gas is cooled by a refrigerant,
The gas can be efficiently cooled.

If the reactor is divided into a plurality of parts and the temperature holding means is disposed between the reactors to cool the gas with a refrigerant, the structure of the temperature holding means can be simplified. can do.

Further, if the reactor is divided into a plurality of parts and the temperature holding means are arranged on the outer surface of the reactor and the gas is cooled by a refrigerant, the temperature holding means can be cooled in the same manner as described above. The configuration can be simplified.

Further, since the temperature holding means has a refrigerant flow rate adjusting means for adjusting the flow rate of the refrigerant based on the temperature of the gas flowing through the reactor or the concentration of carbon monoxide, the selective oxidation function is provided. Can be more reliably maintained in the optimum temperature range in which can be expressed most efficiently, so that the CO oxidation function can be more reliably exhibited than in the case of the above-described embodiment.

Further, if the refrigerant is humidifying water for humidifying a fuel hydrogen gas or an oxidizing gas supplied to a fuel cell,
Since the amount of energy required for heating the humidifying water can be reduced, the efficiency of heat energy can be improved.

Further, if the refrigerant is cooling water for cooling the fuel cell, various members for cooling the fuel cell can be used as temperature holding means, so that the number of members can be reduced and cost can be reduced. The rise can be suppressed.

If the refrigerant is air used as an oxidizing gas to be supplied to the fuel cell, the amount of energy required for heating the oxidizing gas can be reduced, and the efficiency of thermal energy can be increased. .

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a first embodiment when a carbon monoxide removing device according to the present invention is applied to a system for supplying fuel hydrogen gas to a polymer electrolyte fuel cell.

FIG. 2 is a schematic configuration diagram of a second embodiment in which the carbon monoxide removing device according to the present invention is applied to a system for supplying fuel hydrogen gas to a polymer electrolyte fuel cell.

FIG. 3 is a schematic configuration diagram of a third embodiment in which the carbon monoxide removing device according to the present invention is applied to a system for supplying fuel hydrogen gas to a polymer electrolyte fuel cell.

FIG. 4 is a schematic configuration diagram of a fourth embodiment in which the carbon monoxide removing device according to the present invention is applied to a system for supplying fuel hydrogen gas to a polymer electrolyte fuel cell.

FIG. 5 is a schematic configuration diagram of a fifth embodiment in which the carbon monoxide removal device according to the present invention is applied to a system for supplying fuel hydrogen gas to a polymer electrolyte fuel cell.

FIG. 6 is a schematic configuration diagram of a sixth embodiment in which the carbon monoxide removing device according to the present invention is applied to a system for supplying fuel hydrogen gas to a solid polymer electrolyte fuel cell.

FIG. 7 is a schematic configuration diagram of a seventh embodiment in which the carbon monoxide removing device according to the present invention is applied to a system for supplying fuel hydrogen gas to a solid polymer electrolyte fuel cell.

FIG. 8 is a schematic configuration diagram of an example in which a conventional carbon monoxide removing device is applied to a system for supplying fuel hydrogen gas to a polymer electrolyte fuel cell.

FIG. 9 is an explanatory diagram of a power generation principle of a solid polymer electrolyte fuel cell.

FIG. 10 is a graph showing an example of a relationship between a CO concentration in fuel hydrogen gas and power generation characteristics (current density-cell voltage characteristics).

FIG. 11 is a graph showing an example of a relationship between a catalyst temperature and a CO concentration of a reformed gas after treatment in a Ru-based selective oxidation catalyst.

FIG. 12 is a graph showing an example of a relationship between a catalyst temperature and a CO concentration of a reformed gas after treatment in a Pt-based selective oxidation catalyst.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Methanol water 2 Reformed gas 3 Air (oxygen) 4 Oxidizing gas 5 Cooling water 6 Cooling water 7 Air 10, 20, 30, 40, 50, 60, 70 Carbon monoxide removing device 11 Reactor 12 Cooling pipe 13 Cooling Water tank 14 Circulation pump 15 Radiator 31, 32 Valve 41, 42 Flow control valve 43 Temperature sensor 44 Controller 51a First reactor 51b Second reactor 52 Gas radiator 61 Air heat exchanger 62 Air compressor 71a, 71b Cooling Fins 104, 105 Humidifier 106 Cooling line 106a Cooling water pump 107 Solid polymer electrolyte fuel cell 107a Anode 107b Cathode

Claims (8)

[Claims] 1. A carbon monoxide removing apparatus, comprising: a catalyst provided therein for oxidizing carbon monoxide; and a reactor for oxidizing and removing carbon monoxide in a gas flowing through the reactor. A carbon monoxide removing device provided with a temperature holding means for holding the gas flowing inside the gas within a predetermined temperature range. 2. The apparatus for removing carbon monoxide according to claim 1, wherein said temperature holding means is disposed inside said reactor to cool said gas with a refrigerant. 3. The mono-oxidation device according to claim 1, wherein the reactor is divided into a plurality of parts, and the temperature holding means is disposed between the reactors to cool the gas with a refrigerant. Carbon removal equipment. 4. The monoxide according to claim 1, wherein the reactor is divided into a plurality of parts, and the temperature holding means is respectively disposed on an outer surface of the reactor to cool the gas with a refrigerant. Carbon removal equipment. 5. A refrigerant flow rate adjusting means for adjusting a flow rate of the refrigerant based on a temperature of the gas flowing through the reactor or a concentration of carbon monoxide in the reactor. Item 5. A carbon monoxide removing device according to any one of Items 2 to 4. 6. The carbon monoxide removing device according to claim 2, wherein the refrigerant is humidified water for humidifying a fuel hydrogen gas or an oxidizing gas supplied to a fuel cell. 7. The carbon monoxide removing device according to claim 2, wherein the refrigerant is cooling water for cooling a fuel cell. 8. The carbon monoxide removing device according to claim 2, wherein the refrigerant is air used as an oxidizing gas supplied to a fuel cell.