JP2005263584A - H2 generation device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an H<SB>2</SB>generation device which generates a hydrogen-containing gas from a fuel and can supply a sufficient amount of a reformed gas even at a low temperature of not higher than 500°C soon after the start. <P>SOLUTION: The H<SB>2</SB>generation device for generating a hydrogen-containing gas from a fuel is equipped with an O<SB>3</SB>generator in front of a fuel reformer; and an O<SB>3</SB>-containing gas generated by the O<SB>3</SB>generator is introduced into the fuel reformer in fuel reforming. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

The present invention relates to a hydrogen generator (also simply referred to as an H ₂ generator) including a fuel reformer that generates a gas containing hydrogen from a hydrocarbon-based fuel.

  Solid polymer fuel cells are expected to be used as power sources for automobiles and the like because a high current density can be obtained even at a relatively low temperature. An autothermal fuel reformer that uses the amount of heat released from the hydrocarbon oxidation reaction for the hydrocarbon steam reforming reaction as an endothermic reaction is proposed as a source of hydrogen-containing gas for this polymer electrolyte fuel cell Has been.

In such a fuel reformer, for example, hydrocarbon (fuel) such as methanol, air (oxygen), and water vapor (H ₂ O) are mixed, and this is mixed with a copper-based catalyst, a noble metal, or a group VIII (IUPAC inorganic chemical nomenclature). The reformed gas containing hydrogen and carbon dioxide is flown into a reactor filled with a metal-based catalyst (corresponding to the group 8 to 10 after the revised law (1989)), and by a steam reforming reaction represented by the following formula: Generate.

  Here, the steam reforming reaction is shown as an overall reaction by the following two reactions proceeding simultaneously.

  Further, in the fuel reformer, in addition to the reforming reaction, a partial oxidation reaction represented by the following formula is simultaneously occurring.

  Any of the above reforming reactions causes heating or heat generation, and when incorporated as a process, it is often difficult to control the transfer of heat.

  Moreover, the catalyst applied to the above reforming reaction is generally a pellet catalyst, and the pressure loss is large, causing problems such as pulverization due to contact with catalyst particles. On the other hand, a honeycomb-shaped catalyst in which a catalyst base is coated on a ceramic base material made of cordierite has also been proposed, but due to the characteristics of the ceramic base material, moldability is difficult and fixing in the reactor is easy. In addition, since the wall thickness of the base material is thick, there is a limit to coat a large amount of the catalyst component.

  As a means for solving such a problem, Ti, Al, Si, Zr, Ni, Fe, Co, Cu, Zn, Pt, Pd, Ru, A material obtained by coating a metal honeycomb carrier with at least one catalyst selected from Rh has been proposed (see, for example, Patent Document 1).

In the catalyst described in Patent Document 1, since a catalyst having good heat transfer and good base material formability can be provided even in a reforming reaction with endotherm or heat generation, the temperature of the gas at the time of startup The hydrocarbon can be reformed immediately after startup.
JP 2000-126595 A (page 5, FIG. 5)

  However, even if the hydrocarbon-based fuel is reacted using a conventional fuel reformer using the catalyst described in Patent Document 1, as shown in FIG. In the following low temperature range, the reforming performance deteriorates, and there is a problem that sufficient reformed gas cannot be obtained at the time of startup.

In particular, solid polymer fuel cells, which are expected to be used as power sources for mobile vehicles such as fuel cell vehicles, aim to achieve performance equivalent to that of ordinary gasoline engine vehicles, with fuel cell vehicle start-up performance (for example, waiting time from start to start) ) Research and development is underway. In order to supply a large current for driving the motor necessary for starting this fuel cell vehicle, it is not possible to supply electrodes from the outside. Therefore, in addition to the output from an auxiliary power source such as a secondary battery or a capacitor, It is necessary to increase the amount of power generation (fuel cell output). However, in an automobile with a limited mounting space, it is difficult to increase the capacity of such an auxiliary power source, and the amount of power that can be covered by the auxiliary power source is short. Therefore, it is desired to obtain a sufficient amount of power generated by the fuel cell from the earliest possible time, which can contribute to the reduction in size and weight of the auxiliary power supply. Therefore, in order to obtain a sufficient amount of power generated by the fuel cell, as a H ₂ generator used as a supply source of hydrogen-containing gas to the fuel cell, a sufficient amount of modification is possible even in a low temperature region of 500 ° C. or less immediately after startup. The thing which can supply quality gas is anxious.

Therefore, the present invention has been focused on the above-mentioned problems of the prior art, and in a H ₂ generator that generates hydrogen-containing gas from fuel, it is sufficiently improved even in a low temperature range of 500 ° C. or less immediately after startup. and to provide of H ₂ generator that can supply quality gas.

The present invention relates to an H ₂ generator that generates a hydrogen-containing gas from a fuel, and includes an ozone (simply referred to as O ₃ ) generator at the front of the fuel reformer, which is generated by the O ₃ generator. Further, it can be achieved by an H ₂ production apparatus characterized by introducing an O ₃ -containing gas into the fuel reformer during fuel reforming.

In the H ₂ generator of the present invention, O ₃ is generated by installing an ozone generator in front of the fuel reformer, and introduced into the fuel reformer together with reforming raw materials such as fuel. _The reforming reaction can be promoted by the reactivity with the fuel higher than ₂ , the fuel to be reformed increases, and the reformed gas increases. Further, the fuel that crosses with O ₃ and partially reacts with O ₃ is likely to react with water, and promotes the reforming reaction between H ₂ O and the fuel. Since such O ₃ generation can be performed at normal temperature (outside temperature) immediately after startup, it is not necessary to wait for the fuel reformer to warm up to a high temperature range exceeding 500 ° C. As a result, the reforming performance can be improved even in a low temperature range of 500 ° C. or less immediately after startup, and an H ₂ generator capable of supplying a sufficient amount of the reformed gas can be provided.

The H ₂ generator of the present invention is an H ₂ generator that generates a hydrogen-containing gas from a fuel. The H ₂ generator includes an O ₃ generator at the front of the fuel reformer, and the O ₃ generated by the O ₃ generator. _{The 3} containing gas is introduced into the fuel reformer at the time of fuel reforming. In the H ₂ generator of the present invention, by having the above configuration, the reforming performance can be improved in a low temperature range of 500 ° C. or lower.

Hereinafter, typical embodiments of the H ₂ generator of the present invention will be described in detail with reference to specific examples and drawings.

First Embodiment (Example 1)
In Example 1, as a first embodiment of an H ₂ generator that generates a gas containing hydrogen from fuel, a discharge-type O ₃ generator is provided at the front of a fuel reformer, and air is supplied to the O _3. A specific embodiment of the H ₂ production apparatus, which is introduced into the generator and fuel and water are introduced between the O ₃ generator and the fuel reformer will be described.

FIG. 1 schematically shows an outline of a first embodiment of a fuel cell system incorporating the H ₂ generator of the present invention.

As shown in FIG. 1, in this embodiment, a fuel reformer (for example, an autothermal reformer using normal air can be used as in Comparative Example 1 described later) is discharged to the front of the fuel reformer 11. An O ₃ generator 13 of the formula is installed, and air (Air) is introduced into the O ₃ generator 13. By generating O ₃ from air by the H ₂ generator of the present embodiment, the fuel reforming performance can be improved as compared with the autothermal reforming reaction using normal air shown in Comparative Example 1 described later. .

O _{2 in} the air is partially converted to O ₃ by the reaction of 3O ₂ → 2O ₃ by the discharge type O ₃ generator 13. The O ₃ concentration is about 3%, and when the amount of air supplied to the discharge-type O ₃ generator 13 is 0.78 m ³ N / h, the amount of O ₃ generated is about 30 kg / h. In addition, the power consumption in the discharge-type O ₃ generator 13 at that time requires about 30 kW to generate 1 kg / h of O ₃ .

When it is difficult to supply from an external power source as in a fuel cell vehicle, such power is supplied from a secondary battery or capacitor, which is an auxiliary power source, at startup, and then generated by the fuel cell. Supplied from Therefore, even in the case of a fuel cell vehicle, stable supply of O ₃ is possible immediately after startup.

Here, the O ₃ generator mainly includes a discharge type, an electrolysis type, and an ultraviolet lamp type (in the present invention, included in the discharge type).

The O ₃ generator that can be used in the present embodiment may be any generator that can partially convert O ₂ in the air to O ₃ by a reaction of 3O ₂ → 2O _3. The production cost of No. ₃ is the cheapest and can be suitably used. As the discharge type, those using a silent discharge method and a creeping discharge method mainly from the principle of discharge can be used.

In such a discharge-type O ₃ generator, a voltage of several k to 10,000 volts is applied to the air as a voltage to generate electrons due to the discharge, and the electrons dissociate O ₂ to generate O atoms. Thereby, a part of oxygen in the air can be changed to O ₃ . The reaction formula is as follows.

That is, O ₃ (specifically, O ₃ + O ₂ mixed gas) can be obtained as described above by electrically discharging air in the discharge-type O ₃ generator 13.

Next, air containing O ₃ generated by the discharge-type O ₃ generator 13 (specifically, an O ₃ + O ₂ mixed gas) is then mixed with H ₂ O (g; gas) or fuel (fuel (g)). And then fed into the reforming catalyst in the fuel reformer 11. Inside the reformer 11, a gas containing hydrogen is generated by the reforming reaction.

  That is, a gas containing hydrogen can be produced by, for example, a steam reforming reaction of fuel methanol, methane, gasoline, or the like in the fuel reformer 11. For example, the case of performing a reforming reaction using methane as an example is as follows (the following reaction examples illustrate the main reforming reactions of methane, for example, as described below. The reaction for generating hydrogen from the oxygen-containing compound can also proceed in the reformer, and is not limited to these reactions.

From the above reaction mode, the role of O ₃ is considered as follows.

(A) Since O ₃ is more reactive than O ₂ , the amount of reformed fuel increases. Due to the high reactivity, the reaction formula (1) is more likely to proceed even in a low temperature range of 500 ° C. or lower than the reaction formula (2).

(B) The fuel mixed with O ₃ easily reacts with water, and the amount of fuel to be reformed increases. This is because fuel intermingled with O _3, the fuel be a low temperature range below 500 ℃ reacts with O _3, or either in the state, such as oxygen-containing compound, a portion of the fuel It is considered that due to the high reactivity of O ₃ , it was decomposed and more easily reacted with water (see the above reaction formula (4)).

It is thought that the reforming performance is improved as described above. Specifically, the reforming performance represents the following. Improvement of fuel conversion rate, improvement of conversion rate in a low temperature range of 500 ° C. or lower, improvement of H ₂ selectivity, reduction of unreacted fuel such as CO and CH ₄ . Regarding the improvement of the fuel conversion rate and the improvement of the low temperature conversion rate of 500 ° C. or less, the reaction of O ₃ is more reactive than O _2, and the effect that the fuel becomes easier to react, and O ₃ is mixed and reacted. By becoming like an oxygen-containing compound, there exists an effect that it becomes easier to modify | reform. In general, it is known that hydrocarbons having no oxygen such as isooctane are less reactive than compounds such as ethanol and methanol. In addition, the improvement of H ₂ selectivity and the reduction of unreacted fuel such as CO and CH ₄ are also characteristic of oxygen-containing compounds. In general, oxygen-containing compounds such as methanol are Cu and Pd / ZnO. It is known that the use of such a catalyst reduces CO, CH _{4 and the} like and improves H ₂ selectivity (for example, the oxygen-containing compound in the reaction formula (4) is contained in the fuel reformer 11). Under a catalyst such as Cu or Pd / ZnO, it further reacts to produce hydrogen; CH ₂ O + H ₂ O → 2H ₂ + CO ₂ ). Therefore, it is considered that CO 3, CH _{4, and the} like are reduced and H ₂ selectivity is improved by reacting O ₃ with fuel to obtain a fuel such as an oxygen-containing compound.

Here, the fuel that can be used in the present invention is not particularly limited as long as it is a hydrocarbon-based fuel. For example, paraffins whose hydrocarbons are CH ₄ , C ₂ H ₆ , C ₃ H ₈ ; aromatics such as benzene and toluene; olefins such as C ₂ H ₄ and C ₃ H ₆ ; nafurans; , A mixture of kerosene, light oil or the like, or an alcohol such as methanol or ethanol.

In this embodiment, water and fuel are introduced between the fuel reformer 11 and the O ₃ generator 13. If the O ₃ and the fuel are not mixed in advance, the effect as a reforming reaction is reduced. Therefore, it is desirable not to introduce the fuel reformer 11 directly but to introduce it between the fuel reformer 11 and the O ₃ generator 13. Furthermore, when water and fuel are compared, it is more preferable that the fuel reacts with O ₃ before water because the reforming performance is improved because the fuel reacts more easily with the fuel. Therefore, as shown in FIG. 1, the fuel is first introduced into the air containing O ₃ transferred between the fuel reformer 11 and the O ₃ generator 13, and H ₂ O (g ) Is more preferable.

The reforming catalyst used in the fuel reformer 11 is not particularly limited, and many reforming catalysts similar to those used in conventional fuel reformers are used for each type of fuel. It can be applied as it is. For example, taking the case of performing the reforming reaction using methane as a fuel, a catalyst such as Cu or Pd / ZnO that can reduce CO, CH _4, etc. and improve H ₂ selectivity, for example, Selected from Ti, Al, Si, Zr, Ni, Fe, Co, Cu, Zn, Pt, Pd, Ru, and Rh, which are hydrocarbon reforming catalysts having excellent thermal responsiveness described in Japanese Patent No. 126595 (Patent Document 1) A material formed by coating at least one kind of catalyst on a metal honeycomb carrier, Ru, Rh, Ir, Ni described in JP-A No. 2002-126522 etc. is impregnated in an Al ₂ O ₃ or ZrO ₂ carrier, such as a hydrocarbon reforming catalyst, such as those using ZrO 2, _MgO, but still it can be used as a combination thereof as appropriate, are those in any limitation to the cocatalyst component comprising an oxide Not to. That is, the present invention is advantageous in that it is not necessary to newly develop a catalyst used in the fuel reformer in accordance with the O ₃ -containing raw material (fuel + water + O ₂ + O ₃ ) of the present invention. Preferably, it is desirable to appropriately select and use a catalyst type having a higher reforming effect by O ₃ . However, in the present invention, as a catalyst type having a higher O ₃ reforming effect, it was obtained by improving the combination of existing catalyst types, combining, changing the design of the blending ratio, etc., or developing a completely new catalyst type. It goes without saying that things may be used.

Similarly, with respect to the reaction temperature, space velocity, and the like, the conditions used in the conventional fuel reformer can be applied, but they may be appropriately adjusted so that the O ₃ reforming effect becomes higher. That is, the reaction temperature in the fuel reformer may be adjusted in the same manner as in the past depending on the fuel, catalyst type, etc., the temperature is raised (heated up) immediately after startup, and the apparatus is operated from a low temperature range of 200 to 500 ° C. After that, it is generally controlled to stabilize in a high temperature range of 500 to 800 ° C. during steady state, but in the present invention, as described above, good reforming performance is exhibited even in a low temperature range of 500 ° C. or less. Therefore, it can be said that it may be operated in a lower temperature range than in the past. Also, the space velocity may be adjusted in the same manner as in the past, and GHSV (Gas Hourly Space Velocity) = exhaust gas amount (m ³ N / h) / catalyst amount (m ³ ) = 10000 to 300,000 (1 / H), and it is desirable to control within this range. However, at the time of start-up, etc., it is not limited to the above range and may be controlled so that it can quickly shift to a steady state. To do. In addition, the reformer and ozone generator (further, dehumidifiers, shift reactors, prox reactors, fuel cells, etc. described later), in addition to temperature and space velocity, humidity, gas composition (gas concentration), gas In addition to heaters and pumps so that the flow rate (flow velocity), pressure, etc. can be controlled, these control devices, for example, temperature, humidity, pressure, flow rate, gas sensor detection units (measurement units), arithmetic processing units (adjustment) Part), an operation part such as a nozzle or a valve may be provided.

In the H ₂ manufacturing apparatus of the present embodiment, any apparatus having the fuel reformer 11 and the discharge-type O ₃ generator 13 may be used. That is, with H ₂ producing apparatus of this embodiment, O ₃ generator 13 in front of the fuel reformer 11 is provided, has a device structure capable of introducing air into the O ₃ generator 13. Furthermore, what is necessary is just to have an apparatus configuration capable of introducing fuel and water between the fuel reformer 11 and the O ₃ generator 13.

In this embodiment, the outline of the fuel cell system in which the H ₂ manufacturing apparatus is incorporated is shown in a simplified manner. However, the H ₂ manufacturing apparatus of the present invention is limited to application to these fuel cell systems. It is not something. In the fuel cell system of the present embodiment, a shift reactor 15, a prox reactor 17, and a fuel cell 19 are provided in the rear part of the fuel reformer 11 of the H ₂ production apparatus. Moreover, it has an apparatus configuration capable of introducing H ₂ O (g) between the fuel reformer 11 and the shift reactor 15, and between the shift reactor 15 and the prox reactor 17, the prox reactor 17 and the fuel. The apparatus has a device configuration capable of introducing air (oxygen-containing gas) between the batteries 19.

In the fuel cell system shown in the present embodiment, after generating a gas containing hydrogen from the fuel by the H ₂ production apparatus, the gas containing hydrogen from H ₂ production apparatus, H 2 _O introduced _(g) Then, the gas is sent to the shift reactor 15 to perform a shift reaction (CO + H ₂ O → CO ₂ + H ₂ ) to reduce the CO concentration in the hydrogen-containing gas and simultaneously generate hydrogen.

In the fuel cell system incorporating the above-described H ₂ production apparatus of the present invention, the gas composition containing hydrogen coming out of the H ₂ production apparatus differs in concentration due to the improvement of the reforming performance by ozone, but the gas type is It is not different from the conventional fuel reformer. Therefore, the device configuration (catalyst type, catalyst shape, etc.), reaction temperature, space velocity, etc. of the shift reactor 15 and the prox reactor 17 provided at the rear part can be sufficiently applied without any particular change or improvement. Have advantages.

Moreover, carbon monoxide (CO) is produced | generated as a by-product by performing reforming reaction even if it uses any hydrocarbon fuel. That is, when a gas containing hydrogen is produced by a steam reforming reaction of fuel methanol, methane, gasoline, or the like in a conventional fuel reformer, about 1 to 25% of CO is generated as a by-product. However, in this embodiment, since the CO concentration can be reduced by improving the reforming performance, the load on the rear shift reactor 15 and the prox reactor 17 may be light. Therefore, the catalyst life can be improved, and the frequency of maintenance (replacement period) can be reduced, which is advantageous in that the ripple effect on the fuel cell system can be obtained by incorporating the H ₂ production apparatus of the present invention. is there.

  Next, air (oxygen-containing gas) is introduced into the hydrogen-containing gas with reduced CO concentration from the shift reactor 15 and sent to the prox (CO selective oxidation removal) reactor 17 to cover the Pt catalyst electrode of the fuel cell. A selective oxidation removal reaction of poisoning CO is performed, and the CO concentration is reduced to 100 ppm or less, preferably 10 ppm or less, which is a level usable for a fuel cell. The high-purity hydrogen-containing gas and air (oxygen-containing gas) thus obtained are supplied to the fuel electrode and the air electrode of the fuel cell 19, respectively.

(Comparative Example 1)
In Comparative Example 1, a comparative embodiment using a fuel reformer (autothermal reformer) using normal air will be described as an example of a conventional representative H ₂ production apparatus.

  FIG. 6 schematically shows an outline of a fuel cell system using an autothermal reformer using normal air.

In FIG. 6, a fuel reformer (= autothermal reformer) 11 is used as the H ₂ production apparatus, and a shift reactor 15, a prox reactor 17, and a fuel cell 19 are provided in the rear part thereof. The fuel reformer 11 has an apparatus configuration capable of directly introducing fuel, water and air. Furthermore, it has an apparatus configuration capable of introducing H ₂ O (g) between the fuel reformer 11 and the shift reactor 15, and between the shift reactor 15 and the prox reactor 17, the prox reactor 17 and the fuel. The apparatus has a device configuration capable of introducing air (oxygen-containing gas) between the batteries 19.

In the fuel cell system using the fuel reformer 11 shown in this comparative example, by introducing fuel, water and air into the H ₂ production apparatus, a steam reforming reaction is performed, and a gas containing hydrogen is generated from the fuel. Let In the fuel cell system of the present comparative example, as described above, as the gas composition containing hydrogen coming out of the fuel reformer 11, for example, methanol, methane, gasoline, or the like of fuel is used as an existing fuel reformer. Even if a gas containing hydrogen is produced by steam reforming reaction in step 1, since the reforming performance improvement effect by ozone is not obtained, about 1 to 25% of CO is generated as a by-product as usual. Therefore, H ₂ O (g) is introduced into the hydrogen-containing gas from the fuel reformer 11 and sent to the shift reactor 15 to perform a shift reaction (CO + H ₂ O → CO ₂ + H ₂ ). Reduces the CO concentration of hydrogen and at the same time produces hydrogen. Further, air (oxygen-containing gas) is introduced into the hydrogen-containing gas with reduced CO concentration from the shift reactor 15 and sent to the prox (CO selective oxidation removal) reactor 17 to poison the Pt catalyst electrode of the fuel cell. The selective oxidation removal reaction of CO is performed, and the CO concentration is reduced to about 10 to 100 ppm, which is a level usable for a fuel cell. The high-purity hydrogen-containing gas and air (oxygen-containing gas) thus obtained are supplied to the fuel electrode and the air electrode of the fuel cell 19, respectively.

In this comparative example, unlike the first embodiment, the reforming performance improvement effect by ozone immediately after startup cannot be obtained. Therefore, sufficient reformed gas cannot be generated by the fuel reformer 11 in a low temperature range of 500 ° C. or less immediately after startup. As a result, the fuel cell 19 using the reformed gas (hydrogen gas) as a raw material cannot produce a large amount of power generation due to insufficient hydrogen supply. Therefore, the fuel cell 19 cannot sufficiently supply electric power for obtaining a motor driving force necessary for starting and accelerating the automobile. As a result, it was necessary to install a large-capacity auxiliary power source (secondary battery or capacitor) just to cover the shortage of power from the fuel cell immediately after startup, making it difficult to provide a wide interior space. . Alternatively, the car could not be started for ten or more seconds until the temperature reached a high temperature range exceeding 500 ° C. In this embodiment, it can be said that it is extremely useful in that it is not necessary to mount such a standby time and a large-capacity auxiliary power supply. Further, in this comparative example, unlike the first embodiment, since O ₃ cannot be reacted with fuel to make a fuel such as an oxygen-containing compound, the reduction effect of CO, CH _4, etc., and H ₂ selectivity can be obtained. It is difficult to obtain an improvement effect.

Second Embodiment (Example 2)
In Example 2, as a second embodiment of the H ₂ generator that generates hydrogen-containing gas from fuel, a discharge-type ozone generator is provided at the front of the fuel reformer, and the ozone generator A specific example of the H ₂ production apparatus comprising a dehumidifier at the front, introducing air into the dehumidifier, and introducing fuel and water between the ozone generator and the fuel reformer. A specific embodiment will be described.

FIG. 2 schematically shows an outline of the second embodiment of the H ₂ generator of the present invention. The second embodiment is almost the same as the H ₂ generator of the first embodiment in terms of the device configuration, but the difference is that a dehumidifier is installed in front of the discharge type O ₃ generator. Accordingly, in the present embodiment, the fuel cell system other than the H ₂ generator is the same as that in the first embodiment, and therefore the description thereof is omitted including the drawings.

As shown in FIG. 2, in the H ₂ generator of this embodiment, a dehumidifier 21 is further installed in front of the discharge-type O ₃ generator 13, and the apparatus configuration for introducing air into the dehumidifier 21 is as follows. Except for the points provided, the apparatus configuration is the same as that of the H ₂ generator of the first embodiment.

When water is introduced simultaneously with air, the discharge-type ozone generator 13 generates OH radicals decomposed from water, decomposes O ₃ , reduces the yield, and generates nitric acid from nitrogen oxides. This will cause deterioration of the electrode. The nitrogen oxide here is a NO _x component mainly contained in a trace amount in the air. Especially in a fuel cell vehicle applications, such as in running intensive urban, since the exhaust gas components of a gasoline engine vehicle would incorporate a number contained air around while traveling, there is a tendency that the NO _x components is increased. Therefore, it can be said that installation of the dehumidifying device 21 is particularly desirable.

Therefore, in this embodiment, the dehumidifying device 21 is installed, moisture contained in the air is removed, and dry air is sent to the discharge-type O ₃ generator 13 to improve the O ₃ concentration. is there. So obtained, air containing O _3, as compared to the first embodiment of Example 1, since the O ₃ amounts obtained increases, O ₃ concentration is high, further, O ₃ and the fuel Not only promotes the reforming reaction but also facilitates the reaction of the fuel mixed with O ₃ with water, thereby promoting the reforming reaction. Therefore, the modification performance is further improved. Further, in this embodiment, it is possible to suppress deterioration of the electrodes of the discharge type O ₃ generator 13 and to reduce the frequency of repair and replacement of parts. Also in the present embodiment, the reforming improvement effect due to O ₃ can be obtained from the time of startup, so that the reforming performance can be improved in a low temperature range of 500 ° C. or lower. Furthermore, as in Example 1, it is considered that CO 3, CH _4, etc. are reduced and H ₂ selectivity is improved by reacting O ₃ with a fuel to produce a fuel such as an oxygen-containing compound ( The same applies to the following examples).

  The dehumidifying device that can be used in the present invention is not particularly limited, and may be appropriately determined according to the purpose of use.

  General dehumidifiers are roughly classified into the following four types based on the principle and structure.

1) Cooling dehumidifier: cooling coil method, air washer method;
2) Adsorption type dehumidifier: fixed type (two tower switching type), rotary type (rotor type);
3) Absorption type dehumidifier: wet type, dry type (rotor type);
4) Compression type dehumidifier In general, when the dew point temperature of the air after dehumidification is about 5 ° C. or higher, a cooling coil type dehumidifier having a simple structure and handling is widely available. The air washer method using cold water can be used for a stationary fuel cell system rather than a fuel cell system for automobiles with limited mounting space due to the size of the apparatus and water treatment. Further, when a low dew point temperature is required, a cooling dehumidifier or a rotor dehumidifier having a defrosting mechanism can be used effectively. The two-column switching type adsorption type and the wet type absorption type are also larger in size and difficult to handle, so that the stationary type fuel cell system is used rather than the fuel cell system application for automobiles where the mounting space is limited. Used for applications. The rotor type dehumidifier is rarely used alone, and most of them are hybrid type using a cooling type in combination. Compressed dehumidifiers require more power than other systems and require compressed air. Therefore, the compression type dehumidifier is more suitable for stationary fuel cell systems than for automotive fuel cell systems where external power supply is difficult. Available for use. Further, for example, a dehumidifying device filled with a dehumidifying agent that adsorbs moisture such as zeolite may be used, or may be appropriately combined with the above-described device.

  As described above, when applying to a stationary fuel cell system, any dehumidifier can be used. On the other hand, when it is applied to a fuel cell system for automobiles, there is a restriction on the mounting space, and in applications where a reduction in size and weight is required, it is small and lightweight, and maintenance (replacement / replacement work, etc.) is unnecessary as much as possible. It can be said that it is desirable to adopt a high-performance dehumidifier.

  Furthermore, in a fuel cell system application of an automobile, the water removed by the dehumidifying device 21 may be discharged as it is, but it is desirable to collect it and circulate it in the fuel cell system. For example, in FIG. 1, water (g) is introduced at two locations, and it can be said that it is desirable to use them as a part of them.

Third Embodiment (Example 3)
In Example 3, as a third embodiment of the H ₂ generation device that generates hydrogen-containing gas from fuel, an electrolytic O ₃ generator is provided at the front of the fuel reformer, and water is supplied to the O ₂ generator. A specific embodiment of the H ₂ production apparatus, which is introduced into the _three generators and fuel, water, and air are introduced between the O ₃ generator and the fuel reformer will be described. .

FIG. 3 schematically shows the outline of the third embodiment of the H ₂ generator of the present invention. In the third embodiment, an electrolytic O ₃ generator is used instead of the discharge O ₃ generator used in the first and second embodiments. Accordingly, in the present embodiment, the fuel cell system (shift reactor, prox reactor, fuel cell, etc.) other than the H ₂ generator is the same as that in the first embodiment, and the description thereof is omitted including the drawings. To do.

As shown in FIG. 3, in the H ₂ generator of the present embodiment, an electrolytic O ₃ generator 31 is installed in front of the fuel reformer 11.

At the same time, the apparatus configuration for introducing water (liquid; mainly for O ₃ generation) into the electrolysis-type O ₃ generator 31 and only H ₂ gas by-produced in the electrolysis-type O ₃ generator 31 are included. There is also provided a device configuration for selectively separating and introducing the fuel cell into a fuel cell (not shown). Further, an apparatus for introducing fuel (g), air (g) and water (g; for fuel reforming) into the O ₃ -containing gas obtained by the electrolysis-type O ₃ generator 31 or the fuel reformer 11. Except for the point that the configuration is provided, the apparatus configuration is substantially the same as that described in the H ₂ generator of the first and _second embodiments. The order in which the O ₃ -containing gas or the raw material is introduced into the fuel reformer 11 is not limited, for example, the fuel, air, and water may be introduced together or one after another. As described above, it is desirable to introduce the O ₃ -containing gas in the order of fuel, air, and water.

The electrolytic O ₃ generator 31 used in this embodiment has the following characteristics.

Electrolytic formula: When water is electrolyzed at a high density, H ₂ , O ₂ and O ₃ are generated. The reaction formula for O ₃ generation is 3H ₂ O → O ₃ + 6H ₂ . The O ₃ generation concentration is about 20 to 35% by volume. The generated amount is 0.1-1 kg / h. The power consumption is about 100 kW to generate 1 kg / h O ₃ . In the electrolysis type ozone generator 31 used in this embodiment, high concentration of O ₃ can be generated by introducing water immediately after startup, so that the reforming performance is improved in a low temperature range of 500 ° C. or lower. It is done. In particular, the following points are advantageous in that a higher reforming effect than those of Examples 1 and 2 can be obtained.

That is, there are the following differences in the amount of O ₃ generated as compared with the electrolytic and discharge O ₃ generators.

Discharge type: 1 kg / h × 3/100 → 0.03 kW · kg / h (30 kW)
Electrolytic type: 1 kg / h × 20/100 → 2 kW · kg / h (100 kW)
As described above, although the amount of electric power is about three times higher in the electrolysis method, O ₃ having a higher concentration (20%) is generated than in the discharge method, and the amount of O ₃ obtained is increased.

Therefore, by introducing the O ₃ -containing gas obtained by the electrolytic O ₃ generator 31 into the fuel reformer 11, the reactivity (reaction amount) between O ₃ and the fuel is increased, and the high reactivity is achieved. In addition to promoting the reforming reaction, the amount of fuel that has been mixed with O ₃ and easily reformed increases dramatically, and this fuel easily reacts with water to promote the reforming reaction. Therefore, it is considered that the reforming performance is improved as compared with Examples 1 and 2, and the reactivity with the fuel is drastically improved. As a result, a sufficient amount of power generated by the fuel cell can be secured immediately after startup, so that the electric power required by the electrolysis-type O ₃ generator 31 can be supplied by the fuel cell immediately after power generation. Therefore, it is only necessary to supply power from the auxiliary power source to the electrolysis-type O ₃ generator 31 in a very short time immediately after startup, and it can be handled without increasing the capacity of the auxiliary power source. Is possible.

Further, since the amount of O ₃ generated by decomposing water is large, it can be considered that a lower air introduction amount is sufficient as compared with the air introduction amounts of Examples 1 and 2. Therefore, the amount of N ₂ in the air can be reduced, and as a result, higher-purity H ₂ can be obtained. A part of the water supplied to the electrolysis type O ₃ generator 31 may be distributed and supplied from the same water storage tank as the water supplied to the fuel reformer 11. Alternatively, when the water supplied to the fuel reformer 11 is stored in a state of being mixed with the fuel (for example, in the case of a fuel-containing water storage tank), another water storage tank is provided, and from there You may supply. Furthermore, there is no particular limitation such that water generated by the reaction in the fuel cell may be recovered and supplied.

Further, unlike the first and second embodiments, the electrolytic O ₃ generator 31 generates H ₂ , which can be supplied to the fuel cell, which is more advantageous. In order to recover H ₂ from the gas obtained by the electrolysis-type O ₃ generator 31, a conventionally known hydrogen separation technique can be used as appropriate. For example, a hydrogen separation membrane can be used.

Fourth Embodiment (Example 4)
In Example 4, as a fourth embodiment of the H ₂ generator that generates hydrogen-containing gas from fuel, an electrolysis-type O ₃ generator is provided at the front of the fuel reformer, and water is added to the O ₂ generator. ₃ was introduced to the generator, and comprises the O ₃ generator and fuel discharge type of O ₃ generator during reformer, introducing air into the O ₃ generator the discharge type, fuel and water A specific embodiment of the H ₂ production apparatus, which is introduced between the electrolytic O ₃ generator and the fuel reformer, will be described.

FIG. 4 schematically shows the outline of the fourth embodiment of the H ₂ generator of the present invention.

In Example 4, the discharge type O ₃ generator used in Examples 1 and 2 and the electrolysis type O ₃ generator used in Example 3 were combined. Specifically, the air supply unit of the third embodiment is replaced with a discharge-type O ₃ generator. By doing so, the amount of O ₃ obtained is further increased, and the reforming performance is improved as compared with Example 3. Specifically, a discharge type O ₃ generator and O ₃ content air O ₃ concentration of about 3 volume percent obtained by decomposing at 13, O ₃ obtained in O ₃ generator 31 of the electrolysis formula An O ₃ -containing gas having a concentration of about 20 to 35% by volume can be mixed, and a higher concentration of O ₃ can be used for a fuel reforming reaction. Therefore, also in the present embodiment, the reforming improvement effect by O ₃ can be obtained from the time of startup, and thus the reforming performance can be improved in a low temperature range of 500 ° C. or lower. In the present embodiment, the fuel cell system (shift reactor, prox reactor, fuel cell, etc.) other than the H ₂ generator is the same as that in the first embodiment, and the description thereof will be omitted including the drawings. To do.

In the H ₂ generator of the present embodiment, as shown in FIG. 4, in the H ₂ generator of the present embodiment, an electrolytic O ₃ generator 31 is installed in front of the fuel reformer 11.

At the same time, an apparatus configuration for introducing water (liquid; mainly for O ₃ generation) into the electrolysis-type O ₃ generator 31 and H ₂ produced as a by-product in the electrolysis-type O ₃ generator 31. An apparatus configuration for selectively separating only gas and introducing it into a fuel cell (not shown) is also provided. Further, fuel (g), air (g) and water (g; for fuel reforming) are introduced into the O ₃ -containing gas obtained by the electrolysis type O ₃ generator 31 or the fuel reformer 11. A device configuration is provided.

Further, in the H ₂ generator of this embodiment, a discharge-type O ₃ generator 13 is also provided in parallel in the apparatus configuration for introducing the air.

Along with this, the configuration in which air is introduced into the O ₃ generator 13 of the discharge type, and O ₃ content air obtained by the O ₃ generator 13, obtained in the O ₃ generator 31 of the electrolysis formula An apparatus configuration that can be introduced into the O ₃ -containing gas or the fuel reformer 11 is provided. Except for these points is substantially the same apparatus configuration as that described with H ₂ generating device according to the first to the third embodiment.

The fuel and water may be provided between the electrolysis type O ₃ generator 31 and the fuel reformer 11 as shown in FIG. 4, and as shown in FIG. _The supply of the O ₃ -containing gas obtained by the _three generator 31 may be discarded. Or you may make it supply a fuel and water collectively (in the form of the mixture (g) which mixed the fuel and water). Further, the O ₃ -containing air (O ₃ + O ₂ -containing gas) obtained by the discharge-type O ₃ generator 13 is sequentially or collectively supplied, and these are supplied by the electrolysis-type O ₃ generator 31. You may supply to ₃ containing gas. Further, the fuel and water are separated from the O ₃ -containing air obtained by the discharge-type O ₃ generator 13 and the O ₃ -containing gas obtained by the electrolysis-type O ₃ generator 31. May be supplied separately or collectively. However, the present invention is not limited to these. This also applies to Example 5 described later.

Fifth embodiment (Example 5)
In Example 5, as a fifth embodiment of the H ₂ generator for generating a gas containing hydrogen from fuel, an electrolysis type O ₃ generator is provided at the front of the fuel reformer, and water is added to the O ₂ generator. ₃ was introduced to the generator, and the O ₃ with a discharge type of O ₃ generator between the generator and the reformer, and includes a dehumidifier in front of the O ₃ generator the discharge type, air was introduced into the dehumidifier, fuel and water are explained specific embodiments of the H ₂ production apparatus characterized by introducing from between the electrical resolving the O ₃ generator and fuel reformer To do.

FIG. 5 schematically shows the outline of the fifth embodiment of the H ₂ generator of the present invention.

In the fifth embodiment, the relationship between the first and second embodiments is the same as that of the first and second embodiments, and only the dehumidifying device is added compared to the fourth embodiment. Specifically, a dehumidifying device is provided in front of the discharge-type O ₃ generator. Thereby, compared with Example 4, the amount of O ₃ obtained increases and the reforming performance increases dramatically. Moreover, deterioration of the electrode of the discharge-type O ₃ generator 13 can be suppressed, and the frequency of parts repair and replacement can be reduced. Further, in this embodiment, the reforming improvement effect by O ₃ can be obtained from the time of start-up, so that the reforming performance can be improved in a low temperature range of 500 ° C. or lower. In the present embodiment, the fuel cell system (shift reactor, prox reactor, fuel cell, etc.) other than the H ₂ generator is the same as that in the first embodiment, and the description thereof will be omitted including the drawings. To do.

In the H ₂ generator of the present embodiment, as shown in FIG. 5, in the H ₂ generator of the present embodiment, an electrolytic O ₃ generator 31 is installed in front of the fuel reformer 11.

At the same time, an apparatus configuration for introducing water (liquid; mainly for O ₃ generation) into the electrolysis type O ₃ generator 31 and only H ₂ gas by-produced in the O ₃ generator 31 are selected. There is also provided an apparatus configuration for separating them into a fuel cell (not shown). Further, fuel (g), air (g) and water (g; for fuel reforming) are introduced into the O ₃ -containing gas obtained by the electrolysis type O ₃ generator 31 or the fuel reformer 11. A device configuration is provided.

Further, in the H ₂ generator of the present embodiment, the discharge type O ₃ generator 13 is further installed in the apparatus configuration for introducing the air, and a dehumidifier 21 is further provided in front of the discharge O ₃ generator 13.

At the same time, a device configuration for introducing air into the dehumidifying device 21, a device configuration for introducing air dried by the dehumidifying device 21 into the discharge-type O ₃ generator 13, and the discharge-type O ₃ generator 13. A device configuration is provided that can introduce the O ₃ -containing air (O ₃ + O ₂ -containing gas) obtained in step 1 into the O ₃ -containing gas obtained by the electrolysis-type O ₃ generator 31 or the fuel reformer 11. ing. Furthermore, if necessary, a device configuration in which water collected by the dehumidifying device 21 can be used in other fuel cell systems may be provided. Except for these points, the apparatus configuration is substantially the same as that described in the H ₂ generators of the first to fourth embodiments.

  From the above results, when arranged in the order of excellent reforming performance, the order is: Example 5> Example 4> Example 3> Example 2> Example 1.

1 is a schematic view schematically showing an outline of a first embodiment of a fuel cell system incorporating an H ₂ generator of the present invention. The outline of the second embodiment of the H ₂ generation apparatus of the present invention is a schematic diagram schematically showing. Description of the third embodiment of the H ₂ generation apparatus of the present invention is a schematic diagram schematically showing. Description of the fourth embodiment of the H ₂ generation apparatus of the present invention is a schematic diagram schematically showing. The outline of the fifth embodiment of the H ₂ generation apparatus of the present invention is a schematic diagram schematically showing. It is the schematic which represented the outline | summary typically about the fuel cell system using the autothermal reformer using normal air.

Explanation of symbols

11 Fuel reformer (autothermal reformer),
13 Discharge O ₃ generator,
15 shift reactor,
17 prox reactor,
19 Fuel cell,
21 Dehumidifier,
31 Electrolytic O ₃ generator.

Claims (6)

In an H ₂ generator that generates a gas containing hydrogen from fuel,
Equipped with an ozone generator at the front of the fuel reformer,
An H ₂ production apparatus, wherein an ozone-containing gas generated by the ozone generator is introduced into the fuel reformer. In an H ₂ generator that generates a gas containing hydrogen from fuel,
A discharge-type ozone generator at the front of the fuel reformer, introducing air into the ozone generator; and
Fuel and water, H ₂ production apparatus characterized by introducing between the ozone generator and the fuel reformer. In an H ₂ generator that generates a gas containing hydrogen from fuel,
A discharge type ozone generator at the front of the fuel reformer, and a dehumidifier at the front of the ozone generator, introducing air into the dehumidifier; and
Fuel and water, H ₂ production apparatus characterized by introducing between the ozone generator and the fuel reformer. In an H ₂ generator that generates a gas containing hydrogen from fuel,
An electrolytic ozone generator at the front of the fuel reformer, introducing water into the ozone generator; and
Fuel, water and air, H ₂ production apparatus characterized by introducing between the ozone generator and the fuel reformer. In an H ₂ generator that generates a gas containing hydrogen from fuel,
An electrolysis type ozone generator is provided at the front of the fuel reformer, water is introduced into the ozone generator, and a discharge type ozone generator is provided between the ozone generator and the fuel reformer. , Introducing air into the discharge ozone generator,
Fuel and water, H ₂ production apparatus characterized by introducing from between the electric decomposition ozone generator and fuel reformer. In an H ₂ generator that generates a gas containing hydrogen from fuel,
An electrolysis type ozone generator is provided at the front of the fuel reformer, water is introduced into the ozone generator, and a discharge type ozone generator is provided between the ozone generator and the reformer, And equipped with a dehumidifier at the front of the discharge type ozone generator, introducing air into the dehumidifier,
Fuel and water, H ₂ production apparatus characterized by introducing from between the electric decomposition ozone generator and fuel reformer.

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