JP2004231459A - Method and apparatus for generating hydrogen - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for generating only hydrogen through a low-temperature reaction. <P>SOLUTION: In a hydrogen-generating reactor 10, iron carbide 18 is brought into contact with steam or a steam-containing gas (reactant gas) to oxidize and/or hydroxylate the iron carbide and reduce the steam to generate a hydrogen gas, and the hydrogen gas is taken out of an exhaust-gas outlet conduit 22. Here, the thermochemical regeneration effect of iron carbide is enhanced by lowering the reaction temperature to ≤600°C, preferably to 200-500°C, more preferably to 200-400°C, by reducing the steam pressure to the atmospheric pressure or lower, preferably to ≤0.3 atm, more preferably to ≤0.1 atm. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an iron carbide (iron carbide, Fe₃The present invention relates to a method and an apparatus for producing hydrogen using a reaction of generating hydrogen by bringing steam into contact with C).
[0002]
[Prior art]
Hydrogen is not only used as a raw material for lightening (cracking) petroleum and as a raw material for various chemical reactions, such as a reducing gas in the field of steelmaking, but has recently attracted attention as a non-polluting and excellent raw material. In particular, the market for hydrogen has been rapidly expanding due to the commercialization of hydrogen storage alloys that can easily store hydrogen at low cost and the practical use of fuel cells. Under these circumstances, commercialization of a more efficient, less expensive, and simpler method has been awaited instead of the conventional method of producing hydrogen by introducing natural gas and steam into a tube and heating it. And each company is reducing their development.
[0003]
Conventional hydrogen production methods include the electrolysis of water and the reforming of natural gas (hydrocarbon) described above. The method for producing hydrogen by reforming hydrocarbons is a method of mixing and reacting hydrocarbons (gas or liquid) with water vapor to obtain hydrogen, carbon monoxide and carbon dioxide, and separating hydrogen from the gas.
In addition, while studying the process of manufacturing the eye anchor hydride, the present applicant discovered that if water vapor comes into contact with the eye anchor hydride, the eye anchor hydride is converted into iron, and at the same time, hydrogen and carbon monoxide are generated. are doing. That is, they have found that hydrogen is easily generated using water and eye anchor carbide as raw materials. Therefore, as a result of further study, the iron obtained by this reaction can be easily converted back into eye anchor by gas such as carbon monoxide gas generated by the reaction, and almost continuously without the need to replenish eye anchor from outside. It has been found that a process for generating hydrogen can be realized (for example, see Patent Document 1).
[0004]
This process includes components similar to those of the eye anchor hydride manufacturing process, that is, a fluidized bed furnace, a gas heating furnace, a wet dust collector, a gas circulating compressor, and the like, and a device for separating hydrogen gas from gas. This process also means that by storing eye anchor carbide instead of storing hydrogen, it is equivalent to storing hydrogen, and the range of application may be greatly expanded. Further, as the reaction medium, not only the iron anchor hydride manufactured from iron ore, but also the eye anchor hydride manufactured from the pellets obtained by hardening the fine iron powder, or the carbide of other types of substances besides iron can be applied. There is a possibility.
Further, as an application technique of the above-described hydrogen production process, a method and an apparatus for producing hydrogen, generating power, and making iron using iron anchor carbide as a raw material have been developed (for example, see Patent Document 2).
[0005]
[Patent Document 1]
Japanese Patent No. 2954585
[Patent Document 2]
JP-A-2002-194411
[0006]
[Problems to be solved by the invention]
Conventionally, hydrogen production is mainly based on the above-described two methods (water electrolysis and hydrocarbon reforming), but both methods have the following disadvantages.
That is, in the electrolysis of water, expensive electric power is required, so that economically usable hydrogen cannot be obtained. In addition, there is a problem in that energy conversion efficiency is poor because the efficiency in producing electric power is low.
In the reforming of hydrocarbons, a large amount of heat (fuel) is required because the temperature of the heated gas in the gas reformer is 1000 ° C. or higher. For the same reason, the cost of equipment is enormous due to the need for materials that can withstand high temperatures, and the need for various auxiliary facilities for heat recovery of high-temperature exhaust gas. And there is a problem that the main raw materials for hydrogen production are water and expensive natural gas.
[0007]
Further, in the above-described technique of producing hydrogen and carbon monoxide and pure iron by bringing steam into contact with the eye anchor carbide, in order to obtain an economical reaction rate, the temperature is in the range of 400 to 800 ° C., preferably 590. ~ 680 ° C, preferably at a pressure of 10 kg / cm²G or less, preferably 6 kg / cm at atmospheric pressure or more²・ It is desirable to carry out in the range of G or less. However, even though the reaction temperature is relatively low and the steam pressure is relatively low, if hydrogen can be produced at a lower reaction temperature and a lower steam pressure, hydrogen production that is more excellent in energy, cost and operation can be achieved. Become a process. Further, in the above technique, in order to separate hydrogen from generated gas (hydrogen and carbon monoxide), it is necessary to use a membrane separation device, a pressure swing type (PSA) separation device, or the like, but only hydrogen is generated. If it is a reaction, these facilities are not required.
Recent studies have elucidated the reaction mechanism of eye anchor hydride and water in more detail, and have confirmed another hydrogen production reaction at a lower temperature than the above-mentioned hydrogen production reaction.
[0008]
The present invention has been made in view of the above points, and an object of the present invention is to produce hydrogen at a lower reaction temperature and at a lower pressure easily by using iron anchor hydride and water as raw materials. It is possible to use waste heat, etc., and since only hydrogen is generated, a special gas separator is not required, and equipment, raw materials and fuels are inexpensive, so that the price of hydrogen obtained is reduced, energy, An object of the present invention is to provide a method and an apparatus for producing hydrogen which are more excellent in cost, environment and operation.
Further, an object of the present invention is to generate hydrogen by reacting eye anchor hydride with water vapor, oxidized or hydroxylated eye anchor hydride is reduced and regenerated by fossil fuel or the like, and the regenerated eye anchor hydride is again reacted with water vapor. Accordingly, it is an object of the present invention to provide a method and apparatus for producing hydrogen that is superior in energy, cost, environment and operation in terms of converting fossil fuels and the like into hydrogen as a whole process.
[0009]
[Means for Solving the Problems]
In order to achieve the above object, a method for producing hydrogen of the present invention uses an iron carbide (iron carbide, Fe₃C) is configured to contact water vapor or a gas containing water vapor to oxidize and / or hydroxylate eye anchor hydride and to reduce water vapor to generate hydrogen (see FIGS. 1 to 7). In the above method, the reaction temperature is reduced to 600 ° C. or lower, preferably 200 to 500 ° C., and more preferably to lowering the steam pressure to atmospheric pressure or lower, preferably 0.3 atm or lower, more preferably 0.1 atm or lower. By lowering the temperature to 200 to 400 ° C., the thermochemical regeneration effect can be improved. When the reaction temperature is lower than the above lower limit, an economical reaction rate cannot be obtained, while when the reaction temperature is higher than the above upper limit, the hydrogen generation reaction at a low temperature in the method of the present invention is less likely to occur. In addition, a large amount of fuel is required, and there are restrictions on using waste heat. Further, the reaction container is made of a material that can withstand high temperatures, and various additional facilities for heat recovery of high-temperature exhaust gas are required, which increases costs. When the steam pressure exceeds the above upper limit, the hydrogen generation reaction at a low temperature in the method of the present invention does not occur much.
[0010]
Further, in the above method, the thermal energy required for the reaction between the eye anchor hydride and the water vapor can be supplied by bringing the water vapor or another gas into direct contact with the reaction temperature or higher. Further, heat energy necessary for the reaction between the eye anchor hydride and water vapor may be supplied by indirectly contacting a solid, liquid or gas at a temperature higher than the reaction temperature.
[0011]
Further, in the above method, after the generated hydrogen is separated from water vapor and taken out to the outside, the oxidized or / and hydroxylated eye anchor hydride is heated to 600 ° C. or more, preferably 700 ° C. or more, and pure iron and hydrogen are heated. And a gas containing carbon monoxide (see FIG. 3). In this case, it is also possible to adopt a configuration in which at least a part of the generated pure iron is carbonized by carbon monoxide and methane gas to be regenerated into eye anchor hydride, and the regenerated eye anchor hydride is reacted with steam again.
[0012]
In the above method, the generated hydrogen is separated from water vapor and taken out to the outside, and the oxidized or / and hydroxylated eye anchor hydride is reduced by fossil fuel and / or biomass to regenerate the eye anchor hydride and regenerated. It is preferable that the eye anchor hydride be reacted with steam again (see FIGS. 4 to 7). In this case, the oxidized or / and hydroxylated eye anchor hydride can be reduced by natural gas and regenerated into eye anchor hydride (see FIG. 4). In addition, the oxidized and / or hydroxylated eye anchor hydride can be reduced by coal and regenerated into eye anchor hydride (see FIGS. 5 to 7). Specifically, for example, coal and air or oxygen less than the amount required for coal combustion are supplied to the oxidized or / and hydroxylated eye anchor hydride to partially burn the coal to generate carbon monoxide and methane gas. Let's play the eye anchor. Separation of the coal ash generated by the combustion of the coal and the regenerated eye anchor binder, or separation of the coal ash from the oxidized and / or hydroxylated eye anchor binder can be performed by magnetic separation (see FIGS. 6 and 7). ). In these methods, it is preferable that the regeneration of the eye anchor carbide is performed at 600 to 700 ° C., and the sensible heat of the regenerated eye anchor carbide or the like supplies the thermal energy necessary for the reaction between the eye anchor carbide and the water vapor.
[0013]
The hydrogen production apparatus of the present invention holds an eye anchor hydride therein, makes the eye anchor hydride come into contact with water vapor or a gas containing water vapor, oxidizes and / or hydroxylates the eye anchor hydride and reduces water vapor to generate hydrogen. It is characterized by comprising a hydrogen generation reactor to be used and a separating means for separating water vapor contained in gas discharged from the hydrogen generation reactor and extracting hydrogen (see FIG. 2).
[0014]
In addition, the apparatus of the present invention holds an eye anchor hydride therein, and causes steam or a gas containing water vapor to come into contact with the eye anchor hydride to oxidize and / or hydroxylate the eye anchor hydride and reduce water vapor to generate hydrogen. A hydrogen generation reactor to be separated, a separation means for separating water vapor contained in gas discharged from the hydrogen generation reactor to obtain hydrogen, and an oxidized or / and hydroxylated eye anchor hydride from the hydrogen generation reactor. A heating means for heating to generate a gas containing pure iron, hydrogen and carbon monoxide is provided. As an example of the heating means, a fluidized bed heating furnace is used (see FIG. 3).
[0015]
In addition, the apparatus of the present invention holds the eye anchor carbide therein, and makes the eye anchor carbide come into contact with water vapor or a gas containing water vapor to oxidize and / or hydroxylate the eye anchor carbide and reduce the water vapor to generate hydrogen. A hydrogen generation reactor to be separated, a separation means for separating water vapor contained in gas discharged from the hydrogen generation reactor to obtain hydrogen, and an oxidized or / and hydroxylated eye anchor hydride from the hydrogen generation reactor. A regeneration reactor that regenerates the iron anchor by reduction with fossil fuel and / or biomass, and supplies the eye anchor by the regeneration reactor to the hydrogen generation reactor (FIG. 4). To FIG. 7). As the hydrogen generation reactor, an apparatus using a fluidized bed, a fixed bed, a moving bed, a transporting bed, or the like can be used as a means for bringing eye anchor hydride into contact with steam.
[0016]
In the above apparatus, natural gas can be supplied to the regeneration reactor to regenerate the eye anchor hydride (see FIG. 4). Further, coal can be supplied to the regeneration reactor to regenerate the eye anchor hydride (see FIGS. 5 to 7).
Further, in the above-mentioned apparatus, an apparatus using a fluidized bed can be used as a regeneration reactor, and natural gas is blown into the oxidized or / and hydroxylated eye anchor carbide as a flowing gas to reach a high temperature (for example, 600 to 700 ° C.). ), A regenerated high-temperature eye anchor hydride is supplied to the hydrogen generation reactor, and the sensible heat can supply heat energy required for the reaction between the eye anchor hydride and water vapor (FIG. 4). reference).
[0017]
Further, in the above-mentioned apparatus, an apparatus using a fluidized bed can be used as a regeneration reactor, and coal is charged together with the oxidized or / and hydroxylated eye anchor hydride, and the amount required for the combustion of coal as a flowing gas is equal to or less than the amount required. The air or oxygen is blown to partially combust the coal to generate carbon monoxide and methane gas to regenerate the eye anchor hydride (see FIGS. 5 to 7). In this case, a magnetic separator can be provided in a line for supplying the regenerated eye anchor carbide from the regeneration reactor to the hydrogen generation reactor, and the coal ash generated by burning the coal can be separated from the regenerated eye anchor carbide (see FIG. 6). Further, a magnetic separator is provided in a line for supplying the oxidized or / and hydroxylated eye anchor hydride from the hydrogen generation reactor to the regeneration reactor so that coal ash is separated from the oxidized or / and hydroxylated eye anchor hydride. (See FIG. 7). In these devices, the regenerated eye anchor and coal ash or the regenerated eye anchor are supplied to the hydrogen generation reactor, and the heat energy required for the reaction between the eye anchor and steam is supplied by the sensible heat. Can be.
[0018]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail, but the present invention is not limited to the following embodiments, and can be implemented with appropriate modifications.
FIG. 1 shows an apparatus for performing the hydrogen production method according to the first embodiment of the present invention. In FIG. 1, a hydrogen generation reactor 10 is, for example, a reactor composed of a fluidized bed and has a reaction gas (H₂O is a main component, and also contains CO, nitrogen, etc.) is introduced into a wind box 14 from a reaction gas inlet conduit 12 below the hydrogen generation reactor 10 and provided in a gas distributor 16, for example, a gas dispersion plate. It is fed into the hydrogen generation reactor 10 through the holes provided. In addition, as the gas disperser 16, a cap-type one or a diffuser-type one other than the perforated plate can be used. It is also possible to use a reactor such as a moving bed, a fixed bed, or a transport bed as the hydrogen generation reactor 10.
[0019]
In the hydrogen generation reactor 10, Fe₃An anchor carbide 18 mainly composed of C forms a fluidized bed 20, and Fe₃C in the gas passing through the layer₂O (steam) reacts with H₂Gas is generated, and hydrogen gas used as fuel gas or the like is extracted from the exhaust gas outlet conduit 22. In addition, as the reaction medium for hydrogen production, besides the eye anchor hydride manufactured from iron ore or the like, an eye anchor hydride manufactured from fine pellets or the like obtained by solidifying fine iron powder or the like can be used.
The hydrogen generation reaction as described above is represented by the following reaction formula as an example. The reaction mainly occurs according to the reaction formula shown in (1).
Fe₃C + 2H₂O → Fe₃CO₂+ 2H₂          (1)
Fe₃C + 2H₂O → Fe₃C (OH)₂+ H₂      (2)
[0020]
That is, the eye anchor carbide comes into contact with water vapor and changes into hydrogen gas, iron oxide carbide, and iron hydroxide carbide. Theoretically, from the above reaction formula, Fe₃250 Nm from C1 ton³Hydrogen gas, or 125 Nm³Of hydrogen gas. In order to obtain an economical reaction rate, the reaction temperature is 600 ° C. or lower, preferably 200 to 500 ° C., more preferably 200 to 400 ° C., and steam pressure (in the case of a mixed gas, the steam partial pressure ) Is preferably performed at atmospheric pressure or less, preferably at most 0.3 atm, more preferably at most 0.1 atm.
In this case, the heat energy required for the reaction between the eye anchor hydride and the water vapor can be supplied by bringing the water vapor or other gas into direct contact at a temperature higher than the reaction temperature. In addition, heat energy required for the reaction may be supplied by indirectly contacting a solid, liquid, or gas at a reaction temperature or higher.
[0021]
FIG. 2 shows an apparatus for performing the hydrogen production method according to the second embodiment of the present invention. Since the product gas discharged from the hydrogen generation reactor 10 contains unreacted water vapor and the like in addition to the hydrogen gas, the product gas is introduced into the separation means 24 to separate the water vapor and the like, To the outside. As the separating means 24, for example, a wet dust collector that sprays water on the generated gas to clean the gas and reduce water vapor contained in the gas can be used. It should be noted that a reaction gas of 100% steam can be supplied under a low atmospheric pressure. In this case, a membrane separator, a pressure swing type (PSA) gas separator, and the like, such as when hydrogen and carbon monoxide are separated, are used. Not required. Further, since CO is not contained in the generated gas, reforming is not required. Other configurations and operations are the same as those of the first embodiment.
[0022]
FIG. 3 shows an apparatus for performing the hydrogen production method according to the third embodiment of the present invention. In the present embodiment, after hydrogen generated in the hydrogen generation reactor 10 is taken out to the outside (separation means for separating from water vapor and the like is not shown), oxidized eye anchor carbide (iron oxycarbide) or / and hydroxylated carbon is used. The iron anchor (iron hydroxide carbide) is heated to 600 ° C. or higher, preferably 700 ° C. or higher to generate pure iron. As shown in FIG. 3, iron oxycarbide (or / and iron hydroxide carbide) generated by the hydrogen generation reaction in the hydrogen generation reactor 10 is charged into, for example, a fluidized bed heating furnace 26 and heated. Generate pure iron. In this case, after extracting hydrogen to the outside, a non-reactive high-temperature gas (such as nitrogen) is fed into the hydrogen generation reactor 10 to convert iron oxide carbide (or / and iron hydroxide carbide) to pure iron. It is also possible to generate a gas containing hydrogen and carbon monoxide. Other configurations and operations are the same as those in the first and second embodiments.
The reaction for producing pure iron as described above is represented by the following reaction formula as an example.
Fe₃CO₂→ 3Fe + CO₂
Fe₃C (OH)₂→ 3Fe + CO₂+ H₂
Although not shown, at least a part of the generated pure iron is carbonized by a hydrocarbon gas such as carbon monoxide and methane gas to be regenerated into eye anchor hydride. It is also possible to adopt a configuration in which it is supplied and reacted with steam again. An example of the carbonization reaction formula is as follows.
3Fe + CO + CH₄→ Fe₃C + CO + 2H₂
[0023]
FIG. 4 shows an apparatus for performing the hydrogen production method according to the fourth embodiment of the present invention. In FIG. 4, the hydrogen generation reactor 10 is, for example, a reactor composed of a fluidized bed and has a reaction gas (H₂O is a main component, and also contains CO, nitrogen, etc.) is introduced into a wind box 14 from a reaction gas inlet conduit 12 below the hydrogen generation reactor 10 and provided in a gas distributor 16, for example, a gas dispersion plate. It is fed into the hydrogen generating and emitting device 10 through the holes provided. In addition, as the gas disperser 16, a cap-type one or a diffuser-type one other than the perforated plate can be used. It is also possible to use a reactor such as a moving bed, a fixed bed, or a transport bed as the hydrogen generation reactor 10.
[0024]
In the hydrogen generation reactor 10, Fe₃An anchor carbide 18 mainly composed of C forms a fluidized bed 20, and Fe₃C in the gas passing through the layer₂O (steam) reacts with H₂A gas is generated, and hydrogen gas used as a fuel gas or the like is extracted from the exhaust gas outlet conduit 22 (a means for separating the gas from the steam and the like is not shown). In addition, as the reaction medium for hydrogen production, besides the eye anchor hydride manufactured from iron ore or the like, an eye anchor hydride manufactured from fine pellets or the like obtained by solidifying fine iron powder or the like can be used.
The hydrogen generation reaction as described above is represented by the following reaction formula as an example. The reaction mainly occurs according to the reaction formula shown in (1).
Fe₃C + 2H₂O → Fe₃CO₂+ 2H₂          (1)
Fe₃C + 2H₂O → Fe₃C (OH)₂+ H₂      (2)
[0025]
That is, the eye anchor carbide comes into contact with water vapor and changes into hydrogen gas, iron oxide carbide, and iron hydroxide carbide. Theoretically, from the above reaction formula, Fe₃250 Nm from C1 ton³Hydrogen gas, or 125 Nm³Of hydrogen gas. In order to obtain an economical reaction rate, the reaction temperature is 600 ° C. or lower, preferably 200 to 500 ° C., more preferably 200 to 400 ° C., and steam pressure (in the case of a mixed gas, the steam partial pressure ) Is preferably performed at atmospheric pressure or less, preferably at most 0.3 atm, more preferably at most 0.1 atm.
In this case, the thermal energy required for the reaction between the eye anchor hydride and the water vapor can be supplied by bringing the water vapor or another gas into direct contact with the reaction temperature or higher. Further, thermal energy required for the reaction may be supplied by indirectly contacting a solid, liquid or gas at a temperature higher than the reaction temperature.
[0026]
The iron oxycarbide (or / and iron oxycarbide) generated by the hydrogen generation reaction in the hydrogen generation reactor 10 is sent into the regeneration reactor 28 and, for example, forms a fluidized bed 30 and is oxidized and carbonized. Iron (or / and iron hydroxide carbide) reacts with a hydrocarbon gas such as natural gas (methane gas) passing through the layer to form an anchor carbide (iron carbide, Fe₃The state changes to C), and reproduction is performed. The regenerated eye anchor hydride is returned to the hydrogen generation reactor 10. In addition, it is also possible to use hydrocarbon gas other than methane gas as a gas to be added.
Fe₃C + 2H₂O → Fe₃CO₂+ 2H₂        (Hydrogen generation reaction formula)
Fe₃CO₂+ CH₄→ Fe₃C + CO₂+ 2H₂  (Regeneration reaction formula)
[0027]
When a fluidized bed reactor is used as the regeneration reactor 28, that is, when the regeneration of the eye anchor hydride is performed in the fluidized bed, the temperature of the fluidized bed is set to, for example, 600 to 700 ° C., and the regenerated eye anchor hydride is generated by hydrogen generation. By supplying the hydrogen to the reactor 10, the heat energy required for the hydrogen generation reaction can be supplied by the sensible heat of the eye anchor hydride. Various configurations can be applied to the regeneration reactor 28, as in the case of the hydrogen generation reactor 10.
In the present embodiment, hydrogen generated in the hydrogen generation reactor 10 is taken out to the outside, and the oxidized and / or hydroxylated eye anchor hydride is regenerated in the regeneration reactor 28 with the fossil fuel such as natural gas to the eye anchor hydride again. By doing so, it turned fossil fuels into hydrogen as a whole process.
Although not shown, a gas containing hydrogen generated by the above-described regeneration reaction is converted into pure H by a gas separator.₂And other gases (CO₂, Unreacted gas, etc.).
[0028]
FIG. 5 shows an apparatus for performing the hydrogen production method according to the fifth embodiment of the present invention. The configuration, operation, and function of the hydrogen generation reactor 10, the hydrogen generation reaction in the hydrogen generation reactor 10, and the like are the same as those in the fourth embodiment.
As shown in FIG. 5, iron oxycarbide (or / and iron oxycarbide) generated by the hydrogen generation reaction in the hydrogen generation reactor 10 is supplied to the regeneration reactor 28 together with a fossil fuel such as coal or / and biomass. For example, a fluidized bed 30 is formed, and air or oxygen less than an amount required for coal combustion is blown into the regeneration reactor 28 as a fluidizing gas. The supplied coal is partially burned by air or oxygen to generate carbon monoxide and methane gas. Iron oxycarbide (or / and iron oxycarbide) reacts with carbon monoxide, methane gas, etc. passing through the layer to form an anchor carbide (iron carbide, Fe₃C). The regenerated eye anchor hydride is returned to the hydrogen generation reactor 10.
Fe₃C + 2H₂O → Fe₃CO₂+ 2H₂        (Hydrogen generation reaction formula)
Fe₃CO₂+ 3C + 2O₂→ Fe₃C + 3CO₂  (Regeneration reaction formula)
[0029]
When a fluidized bed reactor is used as the regeneration reactor 28, that is, when the regeneration of the eye anchor hydride is performed in the fluidized bed, the temperature of the fluidized bed is set to, for example, 600 to 700 ° C., and the regenerated iron anchor hydride (and coal) By supplying the ash to the hydrogen generation reactor 10, the heat energy required for the hydrogen generation reaction can be supplied by the sensible heat of the eye anchor hydride (and coal ash).
In the present embodiment, hydrogen generated in the hydrogen generation reactor 10 is taken out to the outside, and the oxidized or / and hydroxylated eye anchor hydride is regenerated in the regeneration reactor 28 with iron or fossil fuel such as coal or / and biomass. By regenerating into carbide, fossil fuels and biomass were converted to hydrogen as a whole process.
Other configurations and operations are the same as those in the fourth embodiment.
[0030]
FIG. 6 shows an apparatus for performing the hydrogen production method according to the sixth embodiment of the present invention. In the present embodiment, as shown in FIG. 6, a magnetic separator 32 is provided in a line for supplying the regenerated eye anchor hydride from the regeneration reactor 28 to the hydrogen generation reactor 10, and the coal combustion from the regenerated eye anchor hydride is performed. It separates the coal ash generated in the above. In the present embodiment, when the regeneration of the eye anchor is performed in a fluidized bed, the temperature of the fluidized bed is set to, for example, 600 to 700 ° C., and the regenerated eye anchor is supplied to the hydrogen generation reactor 10, whereby hydrogen is generated. The heat energy required for the generated reaction can be supplied by the sensible heat of the eye anchor hydride. Other configurations and operations are the same as those in the fifth embodiment.
[0031]
FIG. 7 shows an apparatus for performing the hydrogen production method according to the seventh embodiment of the present invention. In the present embodiment, as shown in FIG. 7, a magnetic separator 32 is provided in a line for supplying the oxidized or / and hydroxylated eye anchor hydride from the hydrogen generation reactor 10 to the regeneration reactor 28, and the oxidization and / or It separates coal ash from the hydroxylated eye anchor carbide. In this embodiment, when the regeneration of the eye anchor is performed in a fluidized bed, the temperature of the fluidized bed is set to, for example, 600 to 700 ° C., and the regenerated eye anchor and coal ash are supplied to the hydrogen generation reactor 10. Thus, the heat energy required for the hydrogen generation reaction can be supplied by the sensible heat of the eye anchor hydride and the coal ash. Other configurations and operations are the same as those in the fifth embodiment.
[0032]
【The invention's effect】
The present invention is configured as described above, and has the following effects.
(1) Hydrogen can be easily generated at a lower reaction temperature and a lower pressure using eye anchor carbide and water as raw materials, and low-temperature waste heat can be used, and only hydrogen is generated. For this reason, a special gas separator is not required, and the cost of hydrogen obtained from equipment, raw materials, fuel, and the like is reduced. Further, since CO is not contained in the generated gas, reforming is not required.
(2) Reacting eye anchor hydride with steam to generate hydrogen, oxidized or hydroxylated eye anchor hydride is reduced and regenerated with fossil fuel or the like, and the regenerated eye anchor hydride is reacted again with steam to produce the entirety. This means that fossil fuels and the like were converted to hydrogen as a process.
(3) All the raw materials are clean, rich and non-depleted substances, and it is possible to realize a hydrogen production process that is more excellent in both cost and environment.
(4) By feeding iron oxycarbide and iron hydroxide carbide generated by the hydrogen generation reaction into a fluidized bed heating furnace or the like and heating, not only hydrogen can be produced, but also pure iron can be obtained.
(5) The price of hydrogen obtained is low due to the fact that the equipment is inexpensive, the raw materials are water and eye anchor hydride, and the amount of fossil raw materials such as expensive natural gas used is small.
(6) In addition to the low reaction temperature of hydrogen production, the pressure in the system is lower than the atmospheric pressure, so that the facility costs are reduced and the operation is facilitated.
(7) The temperature of the gas used for the reaction is lower than in other conventional systems. For this reason, fuel consumption can be reduced, various types of fuels other than fossil fuels can be used as well as various fossil fuels, and steam to be added can be handled at the high temperature generally used today, and it can withstand high temperatures There is no need for ancillary equipment for heat recovery of materials and high-temperature exhaust gas, which leads to advantages such as reduced equipment costs.
(8) Reactions such as the water gas reaction (reaction of reducing water vapor with carbon to produce hydrogen) and the steam iron method (reaction of reducing water vapor with iron to produce hydrogen) require a reaction temperature of 800 ° C. or higher. Although it is necessary and combustion of fuel is indispensable, the hydrogen generation reaction of the present invention sufficiently reacts at about 300 ° C., so that it is possible to use waste heat of an engine or the like, thereby improving energy efficiency and reducing CO 2. It has the effect of reducing carbon emissions.
[Brief description of the drawings]
FIG. 1 is a schematic explanatory view showing an apparatus for performing a hydrogen production method according to a first embodiment of the present invention.
FIG. 2 is a schematic explanatory view showing an apparatus for performing a hydrogen production method according to a second embodiment of the present invention.
FIG. 3 is a schematic explanatory view showing an apparatus for performing a hydrogen production method according to a third embodiment of the present invention.
FIG. 4 is a schematic explanatory view showing an apparatus for performing a hydrogen production method according to a fourth embodiment of the present invention.
FIG. 5 is a schematic explanatory view showing an apparatus for performing a hydrogen production method according to a fifth embodiment of the present invention.
FIG. 6 is a schematic explanatory view showing an apparatus for performing a hydrogen production method according to a sixth embodiment of the present invention.
FIG. 7 is a schematic explanatory view showing an apparatus for performing a hydrogen production method according to a seventh embodiment of the present invention.
[Explanation of symbols]
10 Hydrogen generation reactor
12 Reaction gas inlet conduit
14 wind box
16 Gas disperser
18 Eye Anchor Bide
20, 30 fluidized bed
22 Exhaust gas outlet conduit
24 Separation means
26 Heating furnace
28 Regeneration reactor
32 magnetic separator

Claims (25)

A method for producing hydrogen, comprising: contacting water vapor or a gas containing water vapor with an eye anchor hydride to oxidize and / or hydroxylate the eye anchor hydride and reducing the water vapor to generate hydrogen. The hydrogen production method according to claim 1, wherein the reaction is carried out at a steam pressure of not more than atmospheric pressure and a reaction temperature of not more than 600 ° C. The method for producing hydrogen according to claim 1, wherein the reaction is carried out at a steam pressure of 0.3 atm or less and a reaction temperature of 200 to 500 ° C. The method for producing hydrogen according to claim 1, 2 or 3, wherein the heat energy required for the reaction between the eye anchor hydride and the steam is supplied by bringing the steam or another gas into direct contact with the reaction temperature or higher. 4. The hydrogen production method according to claim 1, wherein the heat energy required for the reaction between the eye anchor hydride and the steam is supplied by indirectly contacting a solid, liquid or gas having a reaction temperature or higher. The method according to claim 1, wherein the generated hydrogen is separated from water vapor and taken out to the outside, and then the oxidized and / or hydroxylated eye anchor hydride is heated to 600 ° C. or more to generate a gas containing pure iron, hydrogen and carbon monoxide. A method for producing hydrogen according to any one of claims 1 to 5. The generated hydrogen is separated from water vapor and taken out, and the oxidized or / and hydroxylated eye anchor hydride is reduced by fossil fuel and / or biomass to regenerate the eye anchor hydride, and the regenerated eye anchor hydride reacts with the steam again. The method for producing hydrogen according to any one of claims 1 to 5, The method for producing hydrogen according to claim 7, wherein the oxidized and / or hydroxylated eye anchor hydride is reduced by natural gas to regenerate the eye anchor hydride. The method for producing hydrogen according to claim 7, wherein the oxidized or / and hydroxylated eye anchor hydride is reduced by coal to regenerate the eye anchor hydride. By supplying coal and air or oxygen in an amount less than that required for coal combustion to the oxidized and / or hydroxylated eye anchor hydride, the coal is partially burned, and carbon monoxide and methane gas are generated to regenerate the eye anchor hydride. The method for producing hydrogen according to claim 9. The hydrogen production method according to claim 10, wherein the separation of the coal ash generated by burning the coal and the regenerated eye anchor binder or the separation of the coal ash from the oxidized and / or hydroxylated eye anchor binder is performed by magnetic separation. The hydrogen according to any one of claims 7 to 11, wherein regeneration of the eye anchor carbide is performed at 600 to 700 ° C, and heat energy required for a reaction between the eye anchor carbide and water vapor is supplied by at least sensible heat of the regenerated eye anchor carbide. Production method. 7. The hydrogen production method according to claim 6, wherein at least a part of the generated pure iron is carbonized by carbon monoxide and methane gas to be regenerated into eye anchor hydride, and the regenerated eye anchor hydride is reacted with steam again. A hydrogen generating reactor that holds an eye anchor hydride therein, contacts the gas containing steam or water vapor with the eye anchor hydride, oxidizes or / and hydroxylates the eye anchor hydride and reduces the water vapor to generate hydrogen,
A hydrogen production apparatus comprising: a separation means for separating water vapor contained in a gas discharged from a hydrogen generation reactor and extracting hydrogen. A hydrogen generating reactor that holds an eye anchor hydride therein, contacts the gas containing steam or water vapor with the eye anchor hydride, oxidizes or / and hydroxylates the eye anchor hydride and reduces the water vapor to generate hydrogen,
Separation means for separating water vapor contained in the gas discharged from the hydrogen generation reactor and taking out hydrogen;
A hydrogen producing apparatus comprising: heating means for heating the oxidized or / and hydroxylated eye anchor hydride from the hydrogen generation reactor to generate a gas containing pure iron, hydrogen and carbon monoxide. . The hydrogen production apparatus according to claim 15, wherein the heating means is a fluidized bed heating furnace. A hydrogen generating reactor that holds an eye anchor hydride therein, contacts the gas containing steam or water vapor with the eye anchor hydride, oxidizes or / and hydroxylates the eye anchor hydride and reduces the water vapor to generate hydrogen,
Separation means for separating water vapor contained in the gas discharged from the hydrogen generation reactor and taking out hydrogen;
A regeneration reactor for reducing the oxidized or / and hydroxylated eye anchor hydride from the hydrogen generation reactor with fossil fuel and / or biomass to regenerate the eye anchor hydride, and converting the eye anchor hydride regenerated in the regeneration reactor into hydrogen A hydrogen production apparatus characterized in that it is supplied to a generation reactor. The hydrogen production apparatus according to any one of claims 14 to 17, wherein the hydrogen generation reactor is an apparatus using any one of a fluidized bed, a fixed bed, a moving bed, and a transporting bed as a means for bringing the eye anchor hydride into contact with steam. 19. The hydrogen production apparatus according to claim 17, wherein natural gas is supplied to the regeneration reactor to regenerate the eye anchor hydride. 19. The hydrogen production apparatus according to claim 17, wherein coal is supplied to the regeneration reactor to regenerate eye anchor hydride. The regeneration reactor is a device using a fluidized bed, in which natural gas is blown into the oxidized or / and hydroxylated eye anchor hydride as a fluidizing gas to form a high temperature fluidized bed, and the regenerated high temperature anchor hydride is converted into hydrogen. 19. The hydrogen production apparatus according to claim 17, wherein the hydrogen is supplied to the generation reactor, and the sensible heat supplies thermal energy required for the reaction between the eye anchor hydride and the steam. The regeneration reactor is a device using a fluidized bed, in which coal is charged together with oxidized or / and hydroxylated eye anchor hydride, and air or oxygen less than the amount required for coal combustion is blown in as a fluidizing gas to partially separate the coal. 19. The hydrogen production apparatus according to claim 17, wherein the combustion is performed to generate carbon monoxide and methane gas to regenerate the eye anchor hydride. 23. The hydrogen according to claim 22, wherein a magnetic separator is provided in a line for supplying the regenerated eye anchor carbide from the regeneration reactor to the hydrogen generation reactor, and coal ash generated by coal combustion is separated from the regenerated eye anchor carbide. manufacturing device. A magnetic separator is provided in a line for supplying the oxidized or / and hydroxylated eye anchor hydride from the hydrogen generation reactor to the regeneration reactor, and coal ash is separated from the oxidized or / and hydroxylated eye anchor hydride. 23. The hydrogen production apparatus according to 22. Claims 22 and 23, wherein the regenerated eye anchor and coal ash or the regenerated eye anchor are supplied to a hydrogen generation reactor, and the sensible heat supplies heat energy required for the reaction between the eye anchor and steam. Or the hydrogen production apparatus according to 24.

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