JP2007269525A - Hydrogen-containing gas generator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hydrogen-containing gas generator that can perform catalyst activation appropriately at a low cost. <P>SOLUTION: The hydrogen-containing gas generator 10 comprising a reformer 3 that reforms a raw fuel to form a hydrogen-containing gas, a carbon monoxide converter 4 that converts carbon monoxide contained in the hydrogen-containing gas to carbon dioxide with a carbon monoxide conversion catalyst 4a, and a carbon monoxide remover 5 that selectively oxidizes carbon monoxide contained in the hydrogen-containing gas with a carbon monoxide-removing catalyst 5a comprises a gas-driving means P2 that passes a reduction treatment gas for reducing the carbon monoxide conversion catalyst 4a and the carbon monoxide-removing catalyst 5a through a circulation pathway C comprising the reformer 3, the carbon monoxide converter 4 and the carbon monoxide remover 5, and a moisture-removing means D provided at a position corresponding to immediately before the carbon monoxide remover 5 in the circulation pathway C for separating, in a separator 7, water of condensation prepared in a condenser 6 by condensing the steam in the reduction treatment gas. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a reformer that generates a hydrogen-containing gas containing hydrogen by reforming raw fuel, and carbon monoxide contained in the hydrogen-containing gas is converted to carbon dioxide by a carbon monoxide conversion catalyst. And a carbon monoxide remover that selectively oxidizes carbon monoxide contained in the hydrogen-containing gas after the shift treatment supplied from the carbon monoxide converter by a carbon monoxide removal catalyst. The present invention relates to a contained gas generator.

  As a device for generating a hydrogen-containing gas as a fuel gas for power generation reaction in a fuel cell, a reformer that performs a reforming process of raw fuel to generate a hydrogen-containing gas containing hydrogen, and the hydrogen-containing gas The carbon monoxide converter that converts carbon monoxide contained in the gas into carbon dioxide using a carbon monoxide conversion catalyst, and the carbon monoxide contained in the hydrogen-containing gas after the conversion treatment supplied from the carbon monoxide converter Some have a carbon monoxide remover that is selectively oxidized by a carbon oxide removal catalyst. However, since the problem of poisoning due to carbon monoxide occurs in the electrode cell of the fuel cell, the concentration of carbon monoxide contained in the hydrogen-containing gas supplied to the fuel cell may be reduced to a very low level. is necessary. That is, the catalytic performance of the carbon monoxide conversion catalyst and the carbon monoxide removal catalyst of the carbon monoxide converter of the hydrogen-containing gas generator must be maintained at a high level at all times.

Considering that the oxidation reaction is performed in the carbon monoxide converter and the carbon monoxide remover when generating the hydrogen-containing gas described above, prior to the operation of the hydrogen-containing gas generator, the carbon monoxide converter It is preferable to carry out the reduction treatment of the carbon monoxide shift catalyst and the carbon monoxide removal catalyst of the carbon monoxide remover to activate each catalyst.
For example, in the hydrogen-containing gas generation device described in Patent Document 1, the reduction treatment gas is sequentially passed through a carbon monoxide remover, a carbon monoxide converter, and a reformer, so that the carbon monoxide removal catalyst and The reduction treatment of the carbon oxide conversion catalyst is performed. In this hydrogen-containing gas generating apparatus, the reducing gas is a mixture of nitrogen gas and hydrogen gas at a predetermined concentration, supplied from a gas cylinder, and discarded after flowing through the reformer.

JP 2002-356111 A

  In the hydrogen-containing gas generator described in Patent Document 1, the reduction gas supplied to the carbon monoxide remover, the carbon monoxide converter, and the reformer is discarded after passing through them. It is configured. For this reason, a large amount of gas for reduction treatment is required to perform this reduction treatment, resulting in a problem that the cost required for the reduction treatment increases.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a hydrogen-containing gas generation device that can appropriately activate a catalyst at low cost.

In order to achieve the above object, the hydrogen-containing gas generating device according to the present invention includes a reformer for generating a hydrogen-containing gas containing hydrogen by performing a reforming process on a raw fuel, and the hydrogen-containing gas. A carbon monoxide converter that converts carbon monoxide contained into carbon dioxide using a carbon monoxide conversion catalyst, and carbon monoxide contained in the hydrogen-containing gas after the conversion treatment supplied from the carbon monoxide converter. A hydrogen-containing gas generation device comprising a carbon monoxide remover that is selectively oxidized by a carbon oxide removal catalyst,
Gas for allowing reduction treatment gas for reducing the carbon monoxide conversion catalyst and the carbon monoxide removal catalyst to flow through a circulation path including the reformer, the carbon monoxide conversion device, and the carbon monoxide removal device. Biasing means;
Provided at a location corresponding to the carbon monoxide remover immediately before the carbon monoxide remover in the circulation path of the reduction treatment gas, the condenser condenses water vapor in the reduction treatment gas and is condensed by the condenser. It is in the point provided with the moisture removal means which isolate | separates the condensed water in the said gas for a reduction process with a separator.
In this feature configuration, the water removal means is provided at a position corresponding to the position immediately before the carbon monoxide remover. This means that the water vapor concentration is maintained after the water vapor concentration in the circulation path is reduced by the water removal means. It means a state where the gas flows into the carbon monoxide remover in a state where the gas is removed or the concentration of water vapor is not increased.

According to the above characteristic configuration, the gas urging means converts the reduction treatment gas for reducing the carbon monoxide conversion catalyst and the carbon monoxide removal catalyst into the reformer, the carbon monoxide conversion device, and the one. The water removal means is passed through a circulation path including a carbon oxide remover, and the water removal means is provided at a position corresponding to the immediately before the carbon monoxide remover in the circulation path of the reduction treatment gas. It functions to condense the water vapor in the reducing gas and separate the condensed water in the reducing gas condensed by the condenser with a separator. In other words, the reduction process gas flows through the circulation path including the reformer, the carbon monoxide converter, and the carbon monoxide remover, and the reduction process gas is reused, so that the cost required for the reduction process can be reduced. .
In addition, even if the concentration of water vapor contained in the reduction gas is increased by reducing the carbon monoxide conversion catalyst and the carbon monoxide removal catalyst, the portion corresponding to immediately before the carbon monoxide remover in the circulation path Since the moisture removing means is provided, the carbon monoxide remover is supplied with a dry reduction treatment gas having a low concentration of water vapor. As a result, it is possible to prevent water from adhering to the surface of the carbon monoxide removal catalyst so that the surface area of the carbon monoxide removal catalyst does not decrease, that is, the activity of the catalyst does not decrease.
Therefore, it is possible to provide a hydrogen-containing gas generator that can appropriately activate the catalyst at low cost.

  Another characteristic configuration of the hydrogen-containing gas generation device according to the present invention is that the gas urging means is provided at a position corresponding to the circulation path immediately before the condenser.

  According to the above characteristic configuration, the pressure of the reducing process gas flowing into the condenser is increased, and the dew point of the water vapor contained in the reducing process gas is increased. That is, even if the temperature in the condenser is the same, condensation of water vapor contained in the reduction processing gas is promoted. As a result, the concentration of water vapor contained in the reduction gas flowing into the carbon monoxide remover can be reduced, and water can be effectively prevented from adhering to the surface of the carbon monoxide removal catalyst.

  Another characteristic configuration of the hydrogen-containing gas generation device according to the present invention is that the reduction processing gas is configured to flow into the circulation path from the downstream side of the condenser.

  According to the above characteristic configuration, since the water vapor is liquefied in the condenser, the gas pressure is lowered on the downstream side of the condenser. As a result, the reduction processing gas easily flows into the circulation path.

  Another characteristic configuration of the hydrogen-containing gas generation device according to the present invention is that the gas urging means includes the reduction treatment gas in the order of the carbon monoxide remover, the carbon monoxide converter, and the reformer. The reduction processing gas is energized so as to flow through the circulation path.

  According to the above characteristic configuration, the gas for reduction treatment before being used for the reduction treatment of the carbon monoxide shift catalyst of the carbon monoxide shifter flows into the carbon monoxide remover. As a result, it is possible to effectively prevent water from adhering to the surface of the carbon monoxide removal catalyst by flowing the reduction treatment gas having a low concentration of water vapor into the carbon monoxide remover.

  Another characteristic configuration of the hydrogen-containing gas generation device according to the present invention is that the gas energizing unit is configured such that the gas for reduction treatment is in the order of the reformer, the carbon monoxide converter, and the carbon monoxide remover. The reduction processing gas is energized so as to flow through the circulation path.

  According to the above characteristic configuration, the reduction gas after being used for the reduction treatment of the carbon monoxide conversion catalyst of the carbon monoxide converter is allowed to flow into the carbon monoxide remover. Since it is provided at a position corresponding to the point immediately before the carbon monoxide remover, the concentration of water vapor contained in the reduction gas flowing into the carbon monoxide remover is reduced, and the carbon monoxide removal catalyst is applied to the surface of the carbon monoxide removal catalyst. Water adhesion can be effectively prevented.

Another characteristic configuration of the hydrogen-containing gas generation device according to the present invention includes a desulfurizer that desulfurizes the raw fuel with a desulfurization catalyst, and the desulfurizer and the reformer are desulfurized by the desulfurizer. Connected to supply the reformed raw fuel gas to the reformer,
The desulfurizer is included in the circulation path.

  According to the above characteristic configuration, the raw fuel gas desulfurized by the desulfurizer is connected so as to be supplied to the reformer. It becomes possible to generate a hydrogen-containing gas with a low carbon monoxide concentration while suppressing poisoning by the compound.

<First Embodiment>
Hereinafter, a hydrogen-containing gas generation apparatus 10 according to a first embodiment will be described with reference to the drawings.
FIG. 1 is a functional block diagram of the hydrogen-containing gas generator 10. The hydrogen-containing gas generation apparatus 10 generates a hydrogen-containing gas containing hydrogen by performing a desulfurization process for desulfurizing raw fuel with a desulfurization catalyst 1a and reforming the raw fuel desulfurized by the desulfurizer 1. A reformer 3, a carbon monoxide converter (CO converter) 4 for converting carbon monoxide contained in the hydrogen-containing gas into carbon dioxide by a carbon monoxide conversion catalyst (CO conversion catalyst) 4a, and a monoxide A carbon monoxide remover (CO remover) 5 for selectively oxidizing carbon monoxide contained in the hydrogen-containing gas after the shift treatment supplied from the carbon transformer 4 by a carbon monoxide removal catalyst (CO removal catalyst) 5a; Prepare.

The desulfurizer 1 includes a desulfurization catalyst 1a in which a copper-based or nickel-based oxide catalyst is supported on a support such as a ball-shaped body or a honeycomb-shaped body, and an electric heater 1b that heats the desulfurization catalyst 1a. When the city gas containing methane gas (CH ₄ ) as a main component and added with a sulfur compound as an odorant is used as the raw fuel gas, the desulfurizer 1 first desulfurizes the raw fuel gas to produce the sulfur. Used as a device to remove compounds. In this desulfurization treatment, the desulfurization catalyst 1a is heated to a temperature in the range of 150 to 270 ° C., for example, using the electric heater 1b. Then, the sulfur compound in the raw fuel gas is hydrogenated, and the hydride is adsorbed and desulfurized. Further, the outlet of the desulfurizer 1 and the inlet of the reformer 3 are connected so that the raw fuel gas desulfurized from the desulfurizer 1 is supplied to the reformer 3.

  The reformer 3 includes a reforming catalyst 3a in which a noble metal-based catalyst such as nickel-based or ruthenium is supported on a support such as a ball-shaped body or a honeycomb-shaped body, and a combustor 3b that heats the reforming catalyst 3a. The reaction of the desulfurized raw fuel gas (methane gas) with the steam supplied from the steam generator 2 through the valve V3 is activated by the reforming catalyst 3a to contain hydrogen containing hydrogen and carbon monoxide. It is a device that generates gas. The amount of air supplied to the combustor 3b is adjusted by the valve V4, and the amount of gas fuel supplied to the combustor 3b is adjusted by the valve V5. The amount of heat generated, that is, the temperature of the reforming catalyst 3a is adjusted. During this reforming reaction, the reforming catalyst 3a is maintained at a temperature of, for example, 650 ° C. to 750 ° C. (hereinafter sometimes referred to as “reforming treatment temperature”) using the combustor 3b, and methane gas and steam However, due to the catalytic action of the reforming catalyst 3a, reforming is performed according to the following chemical reaction formula to generate a hydrogen-containing gas. Incidentally, when the hydrogen-containing gas generated by the hydrogen-containing gas generator 10 is consumed in the fuel cell as a fuel gas, the gas fuel supplied to the combustor 3b is the fuel gas discharged from the fuel cell. Some off-gas is used.

[Chemical formula 1]
CH ₄ + H ₂ O → 3H ₂ + CO

  The carbon monoxide converter 4 includes a carbon monoxide conversion catalyst 4a in which an oxide catalyst such as a copper-zinc system or an iron-chromium system is supported on a support such as a ball or honeycomb, and a carbon monoxide conversion catalyst. And an electric heater 4b for heating 4a, which converts carbon monoxide contained in the hydrogen-containing gas supplied from the reformer 3 into carbon dioxide. The conversion of carbon monoxide into carbon dioxide is to prevent electrode poisoning that may occur when carbon monoxide is supplied to the electrode cell of the fuel cell. The carbon monoxide shift catalyst 4a is heated by the electric heater 4b to a temperature in the range of 200 to 300 ° C. (hereinafter also referred to as “shift treatment temperature”), for example, 250 ° C., and carbon monoxide and steam Are activated by the carbon monoxide shift catalyst 4a, and a shift reaction according to the following chemical reaction formula proceeds.

[Chemical formula 2]
CO + H ₂ O → CO ₂ + H ₂

  The carbon monoxide remover 5 heats the carbon monoxide removal catalyst 5a, in which a noble metal catalyst such as platinum, ruthenium or rhodium is supported on a support such as a ball or honeycomb, and the carbon monoxide removal catalyst 5a. And an electric heater 5b that selectively oxidizes unreacted carbon monoxide in the carbon monoxide transformer 4 to carbon dioxide. In the carbon monoxide remover 5, the temperature of the carbon monoxide removal catalyst 5a in the range of 70 to 120 ° C. using the electric heater 5b (hereinafter sometimes referred to as “selective oxidation treatment temperature”), For example, the carbon monoxide heated to a temperature of about 100 ° C. and the catalytic action of the carbon monoxide removal catalyst 5a is selectively oxidized in the hydrogen-containing gas subjected to the modification treatment. Thereby, the carbon monoxide concentration contained in the hydrogen-containing gas supplied to the fuel cell can be made extremely low.

[Production of hydrogen-containing gas]
Hereinafter, a method for generating a hydrogen-containing gas to be supplied to the fuel cell using the hydrogen-containing gas generator 10 shown in FIG. 1 will be described. FIG. 1 is a functional block diagram of a state in which a hydrogen-containing gas is generated in the hydrogen-containing gas generator 10. In this state, the control unit 15 always closes the valves V2, V7, V8, V9, V10, and V11 and also stops the pump P2. The control unit 15 controls the other valves V1, V3, V4, V5, V6 and the pump P1 as described later.

  The controller 15 operates the electric heater 1b, the combustor 3b, the electric heater 4b, and the electric heater 5b to heat the desulfurization catalyst 1a, the reforming catalyst 3a, the carbon monoxide conversion catalyst 4a, and the carbon monoxide removal catalyst 5a. Let Specifically, the control unit 15 adjusts the amount of air supplied to the combustor 3b provided in the reformer 3 by the opening degree of the valve V4, and sets the amount of gas fuel supplied to the combustor 3b to the valve V5. Adjust by opening. As a result, the amount of heat generated from the combustor 3b due to the combustion of the gas fuel, that is, the temperature of the reforming catalyst 3a is adjusted to an appropriate reforming processing temperature. Further, the control unit 15 adjusts the temperature of the carbon monoxide shift catalyst 4a to an appropriate shift treatment temperature by adjusting the amount of current supplied to the electric heater 4b provided in the carbon monoxide shifter 4. As a result, the carbon monoxide transformer 4 is appropriately subjected to the transformation treatment of the hydrogen-containing gas. Further, the control unit 15 adjusts the temperature of the carbon monoxide removal catalyst 5a to an appropriate selective oxidation treatment temperature by adjusting the energization amount to the electric heater 5b provided in the carbon monoxide remover 5. As a result, the carbon monoxide remover 5 appropriately performs selective oxidation of carbon monoxide contained in the hydrogen-containing gas.

  After the desulfurization catalyst 1a, the reforming catalyst 3a, the carbon monoxide conversion catalyst 4a, and the carbon monoxide removal catalyst 5a are heated as described above, the control unit 15 adjusts the opening degree of the valve V1 and the pump P1. And the raw fuel gas is introduced into the desulfurizer 1, and the valve V6 is opened. Further, the control unit 15 controls the amount of steam supplied from the steam generator 2 to the reformer 3 by adjusting the opening of the valve V3. As a result, the desulfurized raw fuel gas and water vapor flow into the reformer 3. Then, the reforming process of the raw fuel gas is appropriately performed in the reformer 3, and a hydrogen-containing gas containing hydrogen is generated. Thereafter, the hydrogen-containing gas generated in the reformer 3 is supplied to the carbon monoxide converter 4.

The hydrogen-containing gas after the shift treatment is supplied to the carbon monoxide remover 5. In the carbon monoxide converter 5, the temperature of the carbon monoxide removal catalyst 5 a is adjusted to an appropriate selective oxidation treatment temperature. Therefore, the selective oxidation of carbon monoxide contained in the hydrogen-containing gas in the carbon monoxide remover 5. Is appropriately performed, and the concentration of carbon monoxide contained in the hydrogen-containing gas is extremely reduced.
As described above, by using the hydrogen-containing gas generation device 10 of this embodiment, a hydrogen-containing gas as a fuel gas for a fuel cell can be generated in a state where the carbon monoxide concentration is very low.

However, in order to make the carbon monoxide concentration contained in the hydrogen-containing gas supplied to the fuel cell very low, the carbon monoxide conversion catalyst 4a is reduced to increase the activity of the carbon monoxide conversion catalyst 4a. There is a need. Similarly, it is necessary to reduce the carbon monoxide removal catalyst 5a to increase the activity of the carbon monoxide removal catalyst 5a. Further, water contained in the hydrogen-containing gas may adhere to the surface of the carbon monoxide removal catalyst 5a, and the surface area of the carbon monoxide removal catalyst 5a that should be exposed may decrease. Therefore, it is necessary to prevent water from adhering to the surface of the carbon monoxide removal catalyst 5a.
Therefore, in the present embodiment, as described below, the carbon monoxide shift catalyst 4a and the carbon monoxide removal catalyst 5a are subjected to reduction treatment before generating a hydrogen-containing gas to be supplied to the fuel cell.

[Reduction treatment of catalyst]
FIG. 2 is a functional block diagram showing a state in which the reduction processing gas is allowed to flow in the hydrogen-containing gas generation device 10 of the first embodiment. In this state, the control unit 15 always closes the valves V1, V3, and V6 and also stops the pump P1. On the other hand, the control unit 15 opens the valves V4 and V5 to burn the combustor 3b, thereby heating the reforming catalyst through which the reduction processing gas flows to a set temperature. Similarly, the control unit 15 operates the electric heater 4b to heat the carbon monoxide shift catalyst, and heats the electric heater 5b to heat the carbon monoxide removal catalyst.

The control unit 15 operates the pump P2 with the valves V7 and V8 opened, and opens the valve V2 to introduce and circulate N ₂ gas into the circulation path C, and then closes the valve V2. Operate. As a result, the inside of the circulation path C is replaced with N ₂ gas as an inert gas. In addition, the control unit 15 operates the condenser 6 to condense the water vapor contained in the gas circulating in the circulation path C, and opens the valve V10 so that the condensed water condensed by the condenser 6 is removed. It is discharged from the separator 7.
In the present embodiment, the condenser 6 includes a cooling unit that cools the flowing gas, and by cooling to a temperature equal to or lower than the dew point of the water vapor contained in the flowing gas, the water vapor contained in the gas. Condensate. As a result, gas and condensed water exist on the downstream side of the condenser 6. In the separator 7, only water is discharged outside the circulation path C through the valve V10. That is, the condenser 6 and the separator 7 function as moisture removing means D that removes water vapor contained in the gas. As a result, the concentration of water vapor contained in the gas flowing downstream of the moisture removing means D is reduced, and a dry gas is obtained. Therefore, since the gas flowing into the carbon monoxide remover 5 is dry, water does not adhere to the surface of the carbon monoxide removal catalyst 5a.

Thus, since the water removal means D is provided in the location corresponding to immediately before the carbon monoxide remover 5 in the circulation path C, a dry gas having a low concentration of water vapor contained in the carbon monoxide remover 5 is provided. Supplied. As a result, it is possible to prevent water from adhering to the surface of the carbon monoxide removal catalyst 5c so that the surface area of the carbon monoxide removal catalyst 5c does not decrease, that is, the activity of the catalyst does not decrease.
In other words, the fact that the water removal means D is provided at a position corresponding to the position immediately before the carbon monoxide remover 5 means that the water vapor concentration is maintained after the water vapor concentration in the gas is reduced by the water removal means D. In this state, the gas flows into the carbon monoxide remover 5 while the concentration of water vapor is not increased. Therefore, as long as the concentration of water vapor in the gas does not increase, another device may be provided in the circulation path C between the moisture removing means D and the carbon monoxide remover 5.

Next, the control unit 15 opens the valve V9 to introduce H ₂ gas into the circulation path C, and prepares a reduction processing gas in which H ₂ gas is mixed with N ₂ gas circulating through the circulation path C. To do. At this time, the control unit 15, so that the gas pressure in the circulation path C as measured by the pressure sensor 8 reaches the set pressure, to adjust the introduction amount of H ₂ gas into the circulation path C. Moreover, since water vapor | steam is liquefied in the condenser 6, the gas pressure becomes low in the downstream of the condenser 6. FIG. As a result, H ₂ as the reduction processing gas easily flows into the circulation path C.

  As described above, in this embodiment, the gas for reduction treatment is circulated in the order of the carbon monoxide remover 5, the carbon monoxide converter 4, the reformer 3, and the desulfurizer 1 by gas energization by the pump P <b> 2. It is energized to flow through C. In addition, since the pump P2 as the gas urging means is provided at a position corresponding to the circulation path C immediately before the condenser 6, the pressure of the reducing gas flowing into the condenser 6 is increased and reduced. The dew point of water vapor contained in the processing gas is increased. That is, even if the temperature in the condenser 6 is the same, the condensation of water vapor contained in the reduction processing gas is promoted. As a result, the concentration of water vapor contained in the reduction gas flowing into the carbon monoxide remover 5 can be reduced, and water can be effectively prevented from adhering to the surface of the carbon monoxide removal catalyst 5a.

The reduction gas prepared as described above on the downstream side of the condenser 6 passes through the separator 7 and then flows into the carbon monoxide remover 5. Then, reduction treatment gas inside the carbon monoxide remover 5, a reduction of the carbon monoxide removal catalyst 5a (or removal of O ₂ by the binding to O ₂ being adsorbed like on the surface of the catalyst) Contribute. As a result, the H ₂ partial pressure in the reduction gas flowing out from the carbon monoxide remover 5 is reduced by the amount consumed by the reduction treatment inside the carbon monoxide remover 5.

The gas for reduction treatment that has flowed out of the carbon monoxide remover 5 then flows into the carbon monoxide converter 4. The reduction gas in the carbon monoxide converter 4 contributes to the reduction process of the carbon monoxide conversion catalyst 4a. As a result, the H ₂ partial pressure in the reducing gas flowing out from the carbon monoxide converter 4 is reduced by the amount consumed by the reducing process inside the carbon monoxide converter 4.

Thereafter, the reduction gas flowing out from the carbon monoxide converter 4 passes through the reformer 3 and the desulfurizer 1 and flows into the condenser 6. The reduction gas returned to the condenser 6 is water vapor taken in through the carbon monoxide remover 5, the carbon monoxide converter 4, the reformer 3, and the desulfurizer 1, particularly water vapor generated by the reduction treatment. Is included. And the water vapor | steam contained in the gas for a reduction | restoration process condenses in the condenser 6. FIG. In this way, the water that existed as water vapor on the upstream side of the condenser 6 becomes liquid water on the downstream side of the condenser 6, so that the gas pressure on the downstream side of the condenser 6 is condensed. It becomes lower than the gas pressure on the upstream side of the vessel 6. That is, it can be said that the decrease in the gas pressure on the downstream side with respect to the upstream side of the condenser 6 is the amount of H ₂ gas consumed by the reduction process.

Therefore, the control unit 15 adjusts the amount of H ₂ gas flowing into the circulation path C based on the measurement result of the pressure sensor 8 that measures the gas pressure in the circulation path C on the downstream side of the condenser 6. Specifically, the control unit 15 causes the H ₂ gas to flow into the circulation path C through the valve V9 so that the gas pressure in the circulation path C on the downstream side of the condenser 6 becomes the initial set pressure. While the reduction process is performed in the carbon monoxide remover 5 and the carbon monoxide converter 4, H ₂ gas is consumed in the reduction process, and therefore, the downstream side of the condenser 6 measured by the pressure sensor 8. The gas pressure will be below the set pressure.
On the other hand, when the reduction process of the carbon monoxide removal catalyst 5a of the carbon monoxide remover 5 and the carbon monoxide conversion catalyst 4a of the carbon monoxide converter 4 is almost completed, the H ₂ gas is not consumed. The gas pressure on the downstream side of the condenser 6 measured in the step does not change at the set pressure.

Therefore, when the gas pressure on the downstream side of the condenser 6 measured by the pressure sensor 8 does not change at the set pressure, the control unit 15 reduces the carbon monoxide removal catalyst 5a and the carbon monoxide shift catalyst 4a. Is determined to be complete. Then, the control unit 15 closes the valves V9 and V10, opens the valve V2, and opens the valve V11. As a result, the reducing path gas existing in the circulating path C is exhausted through the valve V11, and the circulating path C is replaced with N ₂ gas. Then, when the set time has elapsed, the control unit 15 closes the valve V11 and completes the replacement of the circulation path C with N ₂ gas. Thereafter, the control unit 15 closes all the valves and stops the pump P2.

Second Embodiment
In the hydrogen-containing gas generation apparatus of the second embodiment, the installation position of the moisture removing means D is different from that of the first embodiment. Specifically, in the hydrogen-containing gas generation apparatus 20 of the second embodiment, the water removal means D is a location corresponding to the position immediately after the carbon monoxide converter 4 in the circulation path C, and the carbon monoxide remover. 5 is provided at a position corresponding to immediately before 5. Hereinafter, the hydrogen-containing gas generation device of the second embodiment will be described, but the description of the same configuration as that of the first embodiment will be omitted.

[Production of hydrogen-containing gas]
FIG. 3 is a functional block diagram of a state in which a hydrogen-containing gas is generated in the hydrogen-containing gas generation device 20 of the second embodiment. In this state, the control unit 15 always closes the valves V2, V7, V8, V9, and V11, and also stops the pump P2. However, the pump P2 is configured to allow gas to pass even when stopped. That is, when the hydrogen-containing gas generator 20 shown in FIG. 3 generates a hydrogen-containing gas, the control unit 15 operates the condenser 6 and the valve V10 to condense the water vapor contained in the hydrogen-containing gas after the shift treatment. This is the same as the generation of the hydrogen-containing gas in the first embodiment except that the condenser 6 condenses and the condensed water is discharged from the separator 7 via the valve V10.

[Reduction treatment of catalyst]
FIG. 4 is a functional block diagram illustrating a state in which the reduction gas is allowed to flow in the hydrogen-containing gas generation device 20 according to the second embodiment. In this state, the control unit 15 always closes the valves V1, V3, and V6 and also stops the pump P1. On the other hand, the control unit 15 opens the valves V4 and V5 to burn the combustor 3b, thereby heating the reforming catalyst through which the reduction processing gas flows to a set temperature. Similarly, the control unit 15 operates the electric heater 4b to heat the carbon monoxide shift catalyst, and heats the electric heater 5b to heat the carbon monoxide removal catalyst.

The control unit 15 operates the pump P2 with the valves V7 and V8 opened, and opens the valve V2 to introduce and circulate N ₂ gas into the circulation path C, and then closes the valve V2. Operate. As a result, the inside of the circulation path C is replaced with N ₂ gas as an inert gas. In addition, the control unit 15 operates the condenser 6 to condense the water vapor contained in the gas circulating in the circulation path C, and opens the valve V10 so that the condensed water condensed by the condenser 6 is removed. It is discharged from the separator 7.
Thus, since the water removal means D which has the condenser 6 and the separator 7 is provided in the location corresponded just before the carbon monoxide remover 5 in the circulation path C, the carbon monoxide remover 5 includes A dry gas with a low concentration of water vapor is supplied. As a result, it is possible to prevent water from adhering to the surface of the carbon monoxide removal catalyst 5c so that the surface area of the carbon monoxide removal catalyst 5c does not decrease, that is, the activity of the catalyst does not decrease.

Next, the control unit 15 opens the valve V9 to introduce H ₂ gas into the circulation path C, and prepares a reduction processing gas in which H ₂ gas is mixed with N ₂ gas circulating through the circulation path C. To do. At this time, the control unit 15 adjusts the amount of H ₂ gas introduced into the circulation path C so that the gas pressure in the circulation path C measured by the pressure sensor 8 becomes the set pressure. Moreover, since water vapor | steam is liquefied in the condenser 6, the gas pressure becomes low in the downstream of the condenser 6. FIG. As a result, H ₂ as the reduction processing gas easily flows into the circulation path C.

  As described above, in this embodiment, the gas for reduction treatment is circulated in the order of the desulfurizer 1, the reformer 3, the carbon monoxide converter 4, and the carbon monoxide remover 5 by gas energization by the pump P <b> 2. It is energized to flow through C. In addition, since the pump P2 as the gas urging means is provided at a position corresponding to the circulation path C immediately before the condenser 6, the pressure of the reducing gas flowing into the condenser 6 is increased and reduced. The dew point of water vapor contained in the processing gas is increased. That is, even if the temperature in the condenser 6 is the same, the condensation of water vapor contained in the reduction processing gas is promoted. As a result, the concentration of water vapor contained in the reduction gas flowing into the carbon monoxide remover 5 can be reduced, and water can be effectively prevented from adhering to the surface of the carbon monoxide removal catalyst 5a.

The reducing gas prepared as described above on the downstream side of the condenser 6 first flows into the carbon monoxide remover 5. The reduction gas in the carbon monoxide remover 5 contributes to the reduction treatment of the carbon monoxide removal catalyst 5a. As a result, the H ₂ partial pressure in the reduction gas flowing out from the carbon monoxide remover 5 is reduced by the amount consumed by the reduction treatment inside the carbon monoxide remover 5.

Thereafter, the reduction gas flowing out from the carbon monoxide remover 5 is circulated through the desulfurizer 1 and the reformer 3 through the circulation path C and then flows into the carbon monoxide converter 4. The reduction gas in the carbon monoxide converter 4 contributes to the reduction process of the carbon monoxide conversion catalyst 4a. As a result, H ₂ partial pressure of the reducing processing gas flowing out from the carbon monoxide shift converter 4 is reduced by the amount consumed by the reduction process within the carbon monoxide shift converter 4.

Then, the reduction gas flowing out from the carbon monoxide transformer 4 flows into the condenser 6. The reduction gas returned to the condenser 6 is water vapor taken in through the carbon monoxide remover 5, desulfurizer 1, reformer 3, and carbon monoxide converter 4, particularly water vapor generated by the reduction treatment. Is included. And the water vapor | steam contained in the gas for a reduction | restoration process condenses in the condenser 6. FIG. In this way, the water that existed as water vapor on the upstream side of the condenser 6 becomes liquid water on the downstream side of the condenser 6, so that the gas pressure on the downstream side of the condenser 6 is condensed. It becomes lower than the gas pressure on the upstream side of the vessel 6. That is, it can be said that the decrease in the gas pressure on the downstream side with respect to the upstream side of the condenser 6 is the amount of H ₂ gas consumed by the reduction process.

Therefore, the control unit 15 adjusts the amount of H ₂ gas flowing into the circulation path C based on the measurement result of the pressure sensor 8 that measures the gas pressure in the circulation path C on the downstream side of the condenser 6. Specifically, the control unit 15 causes the H ₂ gas to flow into the circulation path C through the valve V9 so that the gas pressure in the circulation path C on the downstream side of the condenser 6 becomes the initial set pressure. While the reduction process is performed in the carbon monoxide remover 5 and the carbon monoxide converter 4, H ₂ gas is consumed in the reduction process, and therefore, the downstream side of the condenser 6 measured by the pressure sensor 8. The gas pressure will be below the set pressure.
On the other hand, when the reduction process of the carbon monoxide removal catalyst 5a of the carbon monoxide remover 5 and the carbon monoxide conversion catalyst 4a of the carbon monoxide converter 4 is almost completed, the H ₂ gas is not consumed. The gas pressure on the downstream side of the condenser 6 measured in the step does not change at the set pressure.

Therefore, when the gas pressure on the downstream side of the condenser 6 measured by the pressure sensor 8 does not change at the set pressure, the control unit 15 reduces the carbon monoxide removal catalyst 5a and the carbon monoxide shift catalyst 4a. Is determined to be complete. Then, the control unit 15 closes the valves V9 and V10, opens the valve V2, and opens the valve V11. As a result, the reducing path gas existing in the circulating path C is exhausted through the valve V11, and the circulating path C is replaced with N ₂ gas. Then, when the set time has elapsed, the control unit 15 closes the valve V11 and completes the replacement of the circulation path C with N ₂ gas. Thereafter, the control unit 15 closes all the valves and stops the pump P2.

<Another embodiment>
<1>
In the above-described embodiment, the control unit 15 adjusts the amount of H ₂ gas that flows into the circulation path C based on the measurement result of the pressure sensor 8. The amount of H ₂ gas may be adjusted.
For example, the amount of the carbon monoxide shift catalyst 4a accommodated in the carbon monoxide remover 4 and the amount of the carbon monoxide remover 5a accommodated in the carbon monoxide remover 5 are known. Therefore, the amount of H ₂ gas required for reduction of carbon monoxide conversion catalyst 4a, and the amount of H ₂ gas required to reduce process carbon monoxide removing catalyst 5a can be easily derived. Therefore, the control unit 15 may adjust the total flow rate of the H ₂ gas flowing into the circulation path C via the valve V9 to perform the reduction process of the carbon monoxide shift catalyst 4a and the carbon monoxide removal catalyst 5a. Alternatively, the control unit 15 may adjust the amount of H ₂ gas that flows into the circulation path C by adjusting the inflow time of the H ₂ gas into the circulation path C. Alternatively, an analyzer for analyzing the gas component in the circulation path C is provided, and the control unit 15 includes a set amount of H ₂ gas in the reduction processing gas flowing through the circulation path C based on the analysis result. As described above, the opening degree of the valve V9 may be adjusted.

<2>
In the above-described embodiment, the case where the H ₂ gas as the reduction processing gas flows into the circulation path C from the downstream side of the condenser 6 has been described, but the H ₂ gas is caused to flow from other parts of the circulation path C. Also good. Further, the inflow position of the N ₂ gas into the circulation path C is not limited to the example shown in FIGS. 1 to 4 and may be changed as appropriate.

<3>
In the above embodiment, methane gas (CH ₄₎ as a main component as the raw fuel gas is provided with the above-described desulfurizer 1 in order to use the city gas sulfur compounds are added as odorant, sulfur compounds When raw fuel gas not contained is used, the desulfurizer 1 may not be provided.

  The hydrogen-containing gas generating apparatus according to the present invention can be used to generate a hydrogen-containing gas having a very low carbon monoxide content at a low cost.

Functional block diagram of a state in which a hydrogen-containing gas is generated in the hydrogen-containing gas generator of the first embodiment Functional block diagram of a state in which the gas for reduction treatment is allowed to flow in the hydrogen-containing gas generation device of the first embodiment Functional block diagram of a state in which a hydrogen-containing gas is generated in the hydrogen-containing gas generator of the second embodiment Functional block diagram of a state in which the gas for reduction treatment is allowed to flow in the hydrogen-containing gas generator of the second embodiment

Explanation of symbols

1 Desulfurizer 3 Reformer 4 Carbon monoxide converter (CO converter)
4a Carbon monoxide conversion catalyst (CO conversion catalyst)
5 Carbon monoxide remover (CO remover)
5a Carbon monoxide removal catalyst (CO removal catalyst)
6 Condenser 7 Separator 10 Hydrogen-containing gas generator C Circulating route D Water removal means P2 pump (gas energizing means)

Claims (6)

A reformer that reforms raw fuel to generate a hydrogen-containing gas containing hydrogen, and carbon monoxide that converts carbon monoxide contained in the hydrogen-containing gas into carbon dioxide by a carbon monoxide shift catalyst. A hydrogen-containing gas generation apparatus comprising: a converter; and a carbon monoxide remover that selectively oxidizes carbon monoxide contained in the hydrogen-containing gas after the shift treatment supplied from the carbon monoxide converter using a carbon monoxide removal catalyst. Because
Gas for allowing reduction treatment gas for reducing the carbon monoxide conversion catalyst and the carbon monoxide removal catalyst to flow through a circulation path including the reformer, the carbon monoxide conversion device, and the carbon monoxide removal device. Biasing means;
Provided at a location corresponding to the carbon monoxide remover immediately before the carbon monoxide remover in the circulation path of the reduction treatment gas, the condenser condenses water vapor in the reduction treatment gas and is condensed by the condenser. A hydrogen-containing gas generating device, comprising: a moisture removing unit that separates condensed water in the gas for reduction treatment with a separator.   The hydrogen-containing gas generating device according to claim 1, wherein the gas urging means is provided at a position corresponding to the position immediately before the condenser in the circulation path.   The hydrogen-containing gas generation device according to claim 1 or 2, wherein the reduction processing gas is configured to flow into the circulation path from a downstream side of the condenser.   The gas energizing means energizes the reduction treatment gas so that the reduction treatment gas flows through the circulation path in the order of the carbon monoxide remover, the carbon monoxide converter, and the reformer. The hydrogen-containing gas generating device according to any one of claims 1 to 3, wherein the hydrogen-containing gas generating device is configured to.   The gas urging means urges the reduction gas so that the reduction gas flows through the circulation path in the order of the reformer, the carbon monoxide converter, and the carbon monoxide remover. The hydrogen-containing gas generating device according to any one of claims 1 to 3, wherein the hydrogen-containing gas generating device is configured to. A desulfurizer for desulfurizing the raw fuel with a desulfurization catalyst, and the desulfurizer and the reformer are connected to supply the raw fuel gas desulfurized by the desulfurizer to the reformer; ,
The hydrogen-containing gas generator according to any one of claims 1 to 5, wherein the desulfurizer is included in the circulation path.

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