KR20120050908A - Apparatus for producing hydrogen gas - Google Patents

Abstract

PURPOSE: An apparatus for manufacturing hydrogen gas is provided to efficiently obtain hydrogen gas by installing a source gas generator and a reactive gas generator in a heat maintaining container. CONSTITUTION: An apparatus for manufacturing hydrogen gas includes a source gas generator(1), a reactive gas generator(2), a hydrogen gas separator(3), and a heat maintaining container(4). The source gas generator generates source gas by vaporizing methanol and water. The reactive gas generator is in connection with the source gas generate and reacts the source gas and oxygen containing gas to obtain reactive gas. The hydrogen gas separator is in connection with the reactive gas generator and separates hydrogen gas form the reactive gas. The heat maintaining container is in connection with the hydrogen gas separator and includes a gas combustor(9). The gas combustor combusts remaining gas after the separation of the hydrogen gas. The reduction of temperatures in the source gas generator and the reactive gas generator is suppressed by installing the generators in the heat maintaining container.

Description

Hydrogen gas production equipment {APPARATUS FOR PRODUCING HYDROGEN GAS}

The present invention relates to a hydrogen gas production apparatus. More specifically, the present invention relates to a hydrogen gas production apparatus and a hydrogen gas production method capable of efficiently producing hydrogen gas.

In recent years, various studies have been made on a production apparatus of hydrogen gas useful for fuel of a fuel cell.

A hydrogen production apparatus with a short start-up time and a simplified configuration and control system of the apparatus, comprising a boiler, a reforming reactor, a shift reactor, and a selective oxidation reactor for generating steam, and each burner for heating the boiler and each reactor. The hydrogen production apparatus provided with is proposed (for example, refer patent document 1). However, since this burner must be equipped with a burner in the boiler and each reactor, it is difficult to miniaturize the whole device, and since the fuel for burning each burner is required, respectively, there is a disadvantage that energy efficiency is low. .

Further, as a hydrogen production apparatus using waste heat as a heat source, an oxygen-containing hydrocarbon vaporizer, a steam generator, an oxygen-containing hydrocarbon / steam mixer, a mixed gas preheater, a reforming reactor, an external heat source, a fruit circulation line, a circulation pump or a circulation blower, and a fruit heater A hydrogen generator having the above has been proposed (see Patent Document 2, for example). However, this hydrogen production apparatus requires a fruit circulation line for circulating the heat transfer medium and requires a mixed gas preheater, an external heat source, and a heat heater as the heat source, so that the apparatus itself is enlarged, and the external heat source and the heating medium heater. Since it requires, it has a disadvantage that the thermal efficiency is low.

Patent Document 1: Japanese Patent Publication No. 2009-114042 Patent Document 2: Japanese Patent Publication No. 2009-292661

This invention is made | formed in view of the said prior art, Comprising: It aims at providing the hydrogen gas manufacturing apparatus which is easy to miniaturize the apparatus itself and can manufacture hydrogen gas efficiently. Another object of the present invention is to provide a hydrogen gas production method that can efficiently produce hydrogen gas and can be suitably applied to a miniaturized hydrogen gas production apparatus.

The present invention,

(1) A hydrogen gas production apparatus for producing hydrogen gas from methanol, comprising: a source gas maker for producing a source gas by vaporizing methanol and water, and a source gas obtained by the source gas maker connected to the source gas maker; A hydrogen gas separator for separating hydrogen gas contained in the reaction gas from a reaction gas obtained by reacting an oxygen-containing gas to produce a reaction gas and the reaction gas manufacturer and reacting the gas produced in the reaction gas manufacturer. And a heat holding container connected to the hydrogen gas separator, the heat gas container having a gas combustion device for burning the remaining gas from which hydrogen gas is separated from the reaction gas in the hydrogen gas separator, wherein the source gas maker and the reactive gas maker include: Open the remaining gas in the gas combustion apparatus; Caused the hydrogen gas production apparatus, it characterized in that it is provided in the vessel such that heat is transferred by boyeol,

(2) A hydrogen gas production method for producing hydrogen gas from methanol, comprising: a raw material gas production process for producing a source gas by vaporizing methanol and water; and a reaction gas for producing a reaction gas by reacting the source gas and an oxygen-containing gas. A hydrogen gas separation step of separating a hydrogen gas contained in the reaction gas from the reaction gas, and a residual gas combustion step of burning the remaining gas from which the hydrogen gas is separated from the reaction gas; Hydrogen gas production method characterized by vaporizing methanol and water in the raw material gas production step by heat generated when burning residual gas in the combustion step, and reacting the raw material gas and the oxygen-containing gas in the reactive gas production step. ,

(3) The hydrogen gas production method according to the above (2), wherein the supply of the oxygen-containing gas is periodically stopped in the reaction gas production step,

(4) The hydrogen gas manufacturing method as described in said (2) or (3) which combusts the said residual gas after mixing a residual gas and an oxygen containing gas in a residual gas combustion process, and

(5) The hydrogen gas manufacturing method in any one of said (2)-(4) which burns a residual gas in presence of a platinum catalyst in a residual gas combustion process.

.

According to the hydrogen gas manufacturing apparatus of this invention, the effect that the apparatus itself can be downsized easily and it can manufacture hydrogen gas efficiently is exhibited. Moreover, the hydrogen gas manufacturing method of this invention has the effect that it can manufacture hydrogen gas efficiently, and can apply to the miniaturized hydrogen gas manufacturing apparatus.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic explanatory drawing which shows one Embodiment of the hydrogen gas manufacturing apparatus of this invention.
It is a schematic explanatory drawing which shows another embodiment of a heat storage container in the hydrogen gas manufacturing apparatus of this invention.

The hydrogen gas production apparatus of the present invention is a hydrogen gas production apparatus for producing hydrogen gas from methanol as described above, and is connected to a source gas maker for producing a source gas by vaporizing methanol and water, and the source gas maker. And a reactant gas manufacturer for reacting the source gas obtained in the source gas maker with the oxygen-containing gas and producing a reaction gas, and connected to the reaction gas maker and included in the reaction gas from the reaction gas obtained in the reactant gas maker. A heat retention container having a hydrogen gas separator for separating hydrogen gas present therein, and a gas combustion device connected to the hydrogen gas separator, for burning residual gas from which hydrogen gas has been separated from a reaction gas in the hydrogen gas separator; Source gas maker and the reactive gas maker, It is characterized in that it is installed in the heat storage container so that heat generated by burning residual gas in the gas combustion device is transferred. In the hydrogen gas production apparatus of the present invention, since the size of the apparatus itself can be easily reduced, the hydrogen gas can be efficiently produced, and methanol, which is easy to be transported and stored, is used as a raw material of hydrogen gas. It has the advantage of being able to produce hydrogen gas.

Moreover, the hydrogen gas manufacturing method of this invention is a hydrogen gas manufacturing method for producing hydrogen gas from methanol as mentioned above, The raw material gas manufacturing process which manufactures source gas by vaporizing methanol and water, The said source gas and oxygen A reaction gas production process for producing a reaction gas by reacting a gas contained therein, a hydrogen gas separation step for separating hydrogen gas contained in the reaction gas from the reaction gas, and a residual gas from which hydrogen gas is separated from the reaction gas is burned. And a remaining gas combustion process, vaporizing methanol and water in the source gas manufacturing process by heat generated when burning the remaining gas in the remaining gas combustion process, and containing the source gas and oxygen in the reaction gas manufacturing process. It is characterized by reacting the gas. According to the hydrogen gas production method of the present invention, since methanol is used as a raw material of hydrogen gas, hydrogen gas can be produced in a required amount when necessary, hydrogen gas can be efficiently produced, and the hydrogen gas can be miniaturized. The effect of being applicable to a manufacturing apparatus appears.

EMBODIMENT OF THE INVENTION Below, the hydrogen gas manufacturing apparatus and hydrogen gas manufacturing method of this invention are demonstrated based on drawing.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic explanatory drawing which shows one Embodiment of the hydrogen gas manufacturing apparatus of this invention. The hydrogen gas generator shown in FIG. 1 includes a source gas maker 1, a reactive gas maker 2, a hydrogen gas separator 3, and a heat storage container 4.

[Raw gas production process]

In the raw material gas production process, the raw material gas is produced by vaporizing methanol and water. In the source gas production process, a source gas maker 1 for producing a source gas by vaporizing methanol and water is used.

As shown in FIG. 1, methanol and water which are raw materials of hydrogen gas are sent to the source gas maker 1 from the pump 5 via the piping 6, for example. The pipes 6 may be provided with valves 7a and 7b as necessary.

The heat exchanger 8 may be provided between the pump 5 and the source gas maker 1 as needed. When the heat exchanger 8 is provided, methanol and water can be heated by the heat exchanger 8 by heat-exchanging with the reaction gas obtained in the reaction gas producer 2, and the reaction obtained in the reaction gas producer 2 is performed. The gas can be cooled by heat exchange with methanol and water. As a result, since methanol and water are heated before being fed to the raw material gas maker 1, there is an advantage that the raw material gas can be efficiently produced.

The amount of water per mol of methanol is preferably 1.2 mol or more, more preferably 1.5 mol or more, from the viewpoint of increasing the yield of hydrogen gas by efficiently generating hydrogen gas and reducing the amount of carbon monoxide gas remaining. Even if it becomes remarkably large, the yield of hydrogen gas does not improve so much, and it is 2.5 mol or less, More preferably, it is 2.0 mol or less from a viewpoint of improving energy efficiency by reducing the quantity of the water with large latent heat of evaporation.

The liquid temperature of methanol and water to be fed to the raw material gas maker 1 is not particularly limited, and may be room temperature or higher than room temperature, but is preferably as high as possible from the viewpoint of improving the yield of hydrogen gas. The upper limit temperature of the liquid temperature is preferably from the boiling point of methanol, from the viewpoint of increasing the energy efficiency.

As the raw material gas maker 1, for example, as shown in FIG. 1, a metal tube etc. which have a spiral shape are mentioned, but this invention is not limited only to this illustration. As a metal used for a metal tube, copper, brass, etc. are mentioned from the point which is excellent in thermal conductivity, including stainless steel, for example.

As shown in FIG. 1, the source gas maker 1 is provided in the heat storage container 4 so as to efficiently transfer heat generated by burning the remaining gas in the gas combustion device 9. In this invention, there is one big characteristic in that the source gas maker 1 is provided in the heat storage container 4 in this way.

In the present invention, since the raw material gas maker 1 is installed in the heat storage container 4 so that heat generated by burning the remaining gas in the gas combustion device 9 is efficiently transferred, it is burned in the heat storage container 4. Since methanol and water are heated and vaporized using the heat of remaining gas, source gas can be manufactured efficiently. Moreover, since the source gas producer 1 is accommodated in the heat storage container 4, there exists an advantage that the hydrogen gas manufacturing apparatus itself of this invention can be miniaturized.

In the embodiment shown in FIG. 1, since the gas combustion device 9 is inserted into the spiral portion of the raw material gas maker 1 including the spirally wound metal tube, the gas combustion device 9 generates the residual gas. Heat is efficiently transferred to the raw material gas maker 1.

This invention is not limited only to embodiment shown in FIG. 1, For example, the source gas producer 1 is the gas combustion apparatus 9 to the extent to which the heat which generate | occur | produced by burning the residual gas in the gas combustion apparatus 9 is transmitted. It may be arrange | positioned with the clearance gap or it may be arrange | positioned in contact with the gas combustor 9 so that the heat produced by burning residual gas in the gas combustor 9 may be directly transmitted.

The raw material gas containing methanol gas and water vapor obtained by vaporizing methanol and water in the raw material gas maker 1 is sent to the reaction gas maker 2 connected with the raw material gas maker 1. For example, as illustrated in FIG. 1, the source gas maker 1 may be connected to the reaction gas maker 2 via a pipe 10 or the like, or may be directly connected to the reaction gas maker 2. good.

In the raw material gas maker 1 shown in FIG. 1, although methanol and water are heated simultaneously, methanol and water do not necessarily need to be heated simultaneously. In the source gas maker 1, the evaporation of methanol and the evaporation of water may be performed separately, or the methanol aqueous solution obtained by mixing methanol and water may be evaporated.

The temperature of the source gas when introducing the source gas into the reaction gas maker 2 is preferably 150 ° C. or more, more preferably from the viewpoint of promoting the oxidation reaction of methanol and reducing the amount of unreacted methanol remaining. Is 200 ° C. or more, and is preferably 300 ° C. or less, more preferably 280 ° C. or less from the viewpoint of suppressing a decrease in the yield of hydrogen gas caused by an increase in the amount of residual gas that is burned in order to increase energy efficiency and bring it to a high temperature. .

[Reaction gas manufacturing process]

In the reaction gas production step, a reaction gas is produced by reacting the raw material gas obtained above with an oxygen-containing gas. In the reaction gas manufacturing process, the reaction gas producer 2 for making the reaction gas react with the source gas obtained by the source gas maker 1 and oxygen containing gas is used.

The raw material gas manufactured by the raw material gas maker 1 is supplied to the reactive gas maker 2 connected with the raw material gas maker 1. In the reaction gas producer 2, a reaction gas is manufactured by reacting a source gas and an oxygen containing gas.

In the present invention, there is one big feature also in that the reactive gas producer 2 is provided in the heat storage container 4.

In the present invention, since the reactive gas producer 2 is provided in the heat storage container 4 in this manner, the reaction occurs by heat generated by burning the remaining gas in the gas combustion device 9 provided in the heat storage container 4. Since the temperature fall resulting from the following reaction formulas (2)-(4) is suppressed in the gas maker 2, hydrogen gas can be produced efficiently. Moreover, since the reactive gas producer 2 is accommodated in the heat storage container 4 together with the source gas maker 1, there exists an advantage that the hydrogen gas manufacturing apparatus itself can be miniaturized.

Since the reactive gas producer 2 shown in FIG. 1 is provided with a clearance from the gas combustion apparatus 9, the heat generated from the gas combustion apparatus 9 is transmitted to the reactive gas producer 2 via the said clearance. . The reactive gas producer 2 may be provided in contact with the gas combustion device 9 without providing the gap.

In the reaction gas maker 2, a source gas and an oxygen containing gas react, and Formula (1):

CH ₃ OH + 0.5O ₂ → CO ₂ + 2H ₂ (1)

As indicated by, methanol is oxidized to produce hydrogen gas and carbon dioxide gas. Since the oxidation reaction of this methanol is exothermic reaction, the temperature in the system of the reaction gas producer 2 rises.

In parallel with the oxidation reaction of methanol, part of the methanol does not participate in oxygen gas, and the equation (2):

CH ₃ OH → CO + 2H ₂ (2)

Decomposed into carbon monoxide gas and hydrogen gas, as represented by Eq. (3):

CH ₃ OH + H ₂ O → CO ₂ + 3H ₂ (3)

As indicated by, it is decomposed into carbon dioxide gas and hydrogen gas. Since this decomposition reaction is an endothermic reaction, part of the heat generated in the oxidation reaction is canceled out. As a result, the temperature in the system of the reaction gas maker 2 becomes a temperature to some extent low compared with the case where only the said oxidation reaction takes place. Moreover, in addition to these reactions, Formula (4):

CO + H ₂ O → H ₂ + CO ₂ (4)

It is thought that a shift reaction represented by.

The oxygen-containing gas may be introduced into the reaction gas maker 2 separately from the source gas, but from the viewpoint of generating hydrogen gas continuously, the raw material mixed gas obtained by mixing the source gas and the oxygen-containing gas may be reacted with the reaction gas maker ( It is preferable to introduce into 2).

In the case where the raw material mixed gas is introduced into the reaction gas manufacturer 2, for example, as shown in FIG. 1, the pipe 10 and the pipe 11 for the oxygen-containing gas may be T-shaped pipes, Y-shaped pipes, or the like (not shown). By connecting through the raw material gas and the oxygen-containing gas, the raw material mixed gas obtained can be introduced into the reaction gas manufacturer 2 through the pipe 12. In addition, the oxygen-containing gas may be introduced into the reaction gas maker 2 independently of the source gas through a pipe separate from the source gas. In the piping 11 for oxygen containing gas, the valve 13 may be provided in order to control the introduction amount of the oxygen containing gas.

Since the oxygen-containing gas has a smaller heat capacity as compared to methanol and water, there is no need to heat the oxygen in particular, but for example, a pipe of the oxygen-containing gas is introduced into the heat storage container 4 to remain in the gas combustion device 9. After heating the piping of the said oxygen containing gas with the heat of combustion of gas, you may introduce the oxygen containing gas into the reaction gas manufacturer 2 from the said piping.

As the oxygen-containing gas, for example, a mixed gas of an inert gas such as nitrogen gas, argon gas, and oxygen gas, as well as air and oxygen gas, may be cited. However, the present invention is not limited only to these examples.

The amount of oxygen gas contained in the oxygen-containing gas per mol of methanol is preferably 0.05 mol or more, more preferably 0.1 mol or more, from the viewpoint of reducing the amount of unreacted methanol remaining, and hydrogen generated from methanol. From the viewpoint of avoiding an increase in the reaction temperature due to the reaction between the gas and the oxygen gas, and avoiding consumption of the generated hydrogen gas by the reaction of the oxygen gas, the content is preferably 0.25 mol or less, and more preferably 0.2 mol or less. .

When reacting the source gas and the oxygen-containing gas in the reaction gas producer 2, it is preferable to use a catalyst from the viewpoint of increasing the generation efficiency of the hydrogen gas. The catalyst is usually used by filling into a reactor (not shown).

Examples of the catalyst include platinum group catalysts such as platinum and palladium, copper catalysts, and the like, but the present invention is not limited only to these examples. As a copper type catalyst, copper oxide containing the particle which copper oxide was impregnated on the surface of particle | grains containing metal oxides, such as a cerium oxide, a zirconium oxide, titanium oxide, magnesium oxide, a gallium oxide, an indium oxide, for example Although a system catalyst etc. are mentioned, this invention is not limited only to this illustration.

Among the catalysts, from the viewpoint of heat resistance, CuO / Al ₂ O ₃ and CuO / ZnO / Al ₂ O ₃ are preferable, and CuO / Al ₂ O ₃ is more preferable. Since the heat-resistant temperature of CuO / ZnO / Al ₂ O ₃ is generally 300 ° C. or less, at higher temperatures, the catalytic activity decreases with time by sintering. In contrast, CuO / Al ₂ O ₃ has the advantage that sintering is unlikely to occur even when heated to a high temperature of about 600 ° C., in contrast to CuO / ZnO / Al ₂ O ₃ .

The particle diameter of the catalyst is preferably 0.5 mm or more, more preferably 1 mm or more from the viewpoint of improving the air permeability of the raw material mixed gas in the gap between the catalyst particles, and the viewpoint of increasing the contact efficiency between the catalyst and the raw material mixed gas. Is preferably at most 20 mm, more preferably at most 10 mm.

The amount of the catalyst is different depending on the shape of the catalyst layer and the like, but is usually about 20 to 300 ml per 1 g / min of methanol sent to the reaction gas producer 2. The length of the catalyst layer is not particularly limited, and it is preferable to set the raw material mixed gas to remain in the catalyst layer for a certain time, but it is usually about 0.5 to 5 m.

The residence time of the raw material mixed gas in the catalyst layer is represented by the formula (I):

[Retention time of raw material mixed gas]

= [Column volume in reactor]

÷ [volume at standard state of raw material mixed gas introduced in unit time] (I)

Can be obtained based on Here, the empty column volume means the internal volume of the reactor which is not filled with a catalyst, and the volume in the standard state of the raw material mixed gas means the volume of the raw material mixed gas at 1 atm and 0 ° C. The residence time of the raw material mixed gas in the catalyst layer is preferably 0.5 seconds or more, more preferably 1 second or more from the viewpoint of improving the yield of hydrogen gas by reducing the amount of methanol remaining, and rapidly producing hydrogen gas. By the viewpoint of improving manufacturing efficiency by doing so, Preferably it is 10 second or less, More preferably, it is 5 second or less.

The catalyst layer can be used in various forms. In the form of a catalyst layer, for example, a plate-shaped catalyst layer in which a catalyst layer is sandwiched between two metal plates, a columnar catalyst layer in which a catalyst is filled in a cylindrical body having a rectangular or circular cross-sectional shape, and two cylindrical shapes concentrically The sieves overlap each other, and a cylindrical catalyst layer filled with a catalyst in the gap between these cylindrical bodies, a parallel catalyst layer in which a plurality of the columnar catalysts are arranged in parallel, and the like, but the present invention is not limited to these examples. .

When viewed from the vertical direction of the reaction gas flow in the reaction gas producer 2, the distance from the center of the catalyst layer to the base wall of the reaction gas producer 2 is a gas combustion device provided in the heat storage container 4. From the viewpoint of allowing the heat from (9) to be efficiently transferred to the center of the catalyst layer, it is preferably within 4 cm. For example, in the case of a catalyst layer having a thickness of 8 cm, the distance from the center of the catalyst layer to the base wall of the reaction gas producer 2 is 4 cm.

Again, generally formula (II):

[Equivalent diameter] = ([cross-sectional area of catalyst layer] ÷ [base wall length in contact with catalyst]) x 4 (II)

The equivalent diameter represented by is preferably 16 cm or less from the viewpoint of efficiently heating up to the center of the catalyst layer, and preferably 2 cm or more from the viewpoint of efficiently producing the reactor. The equivalent diameter is, for example, 16 cm when the plane is placed 8 cm apart, and 16 cm even when one side is a 16 cm square pillar. The two cylindrical bodies overlap each other in concentric circles, and these cylinder shapes In the case where the catalyst is filled in the gap between the upper bodies, even when the difference between the diameters of the two cylindrical bodies is 16 cm, the diameter becomes 16 cm.

The supply rate of the raw material mixed gas supplied to the catalyst layer is a value obtained by dividing the amount of the raw material mixed gas in the standard state by the cross-sectional area of the catalyst layer (hereinafter referred to as linear velocity). Is preferably at least 0.2 m / sec, more preferably at least 0.4 m / sec, and from the viewpoint of suppressing the reaction temperature from increasing, preferably at most 2 m / sec, more preferably at most 1.5 m / sec. to be.

As the raw material mixed gas introduced into the catalyst layer proceeds inside the catalyst layer, the temperature of the catalyst layer is increased by the oxidation reaction. The reaction temperature of the raw material mixed gas is from the viewpoint of avoiding remaining of unreacted methanol and generally from the viewpoint of preventing endothermic reaction of the raw material mixed gas from occurring on the downstream side of the catalyst layer, and preventing the reaction rate from decreasing as the reaction temperature decreases. Preferably it is 220 degreeC or more, More preferably, it is 240 degreeC or more, More preferably, it is 260 degreeC or more. In addition, the reaction temperature of the raw material mixed gas is preferably 550 ° C. or less, more preferably 500 ° C. or less, and even more preferably 450 ° C. or less from the viewpoint of keeping the catalyst activity stable for a long time.

In the case where a copper-based catalyst is used as the catalyst, the reaction temperature rises with time as the oxidation reaction occurs in the catalyst layer. This is, for example, when using CuO / Al ₂ O ₃ as the copper-containing catalyst, the formula (2) to the reaction represented by the formula (4), CuO / Al ₂ O ₃ reduced chain Cu / Al ₂ O ₃ of In the phase where the oxidation reaction occurs, Cu / Al ₂ O ₃ is gradually oxidized to CuO / Al ₂ O ₃ . As a result, since the reactions represented by the formulas (2) to (4) are less likely to proceed, the heat generation is remarkable because only the oxidation reaction occurs preferentially, and the reaction temperature is gradually increased, so that the catalyst life is shortened. .

Therefore, as a result of earnest research by the present inventors regarding the method of suppressing the reaction temperature from increasing, it was found that the supply of the oxygen-containing gas should be stopped regularly. In this way, when the supply of the oxygen-containing gas to the catalyst layer is stopped regularly, since the catalyst layer of the oxidation reaction portion is reduced by contact with a reducing substance such as methanol, Cu / Al ₂ having a catalytic activity of CuO / Al ₂ O ₃ It is thought to be modified with O ₃ .

The period for stopping the supply of the oxygen-containing gas to the catalyst layer is preferably 10 seconds to 1 hour, more preferably 10 seconds to 10 minutes from the viewpoint of restoring the catalytic activity and increasing the production efficiency of the hydrogen gas. The time for stopping the supply of the oxygen-containing gas to the catalyst layer is, from the viewpoint of restoring the catalytic activity and increasing the production efficiency of the hydrogen gas, the supply of the oxygen-containing gas to the catalyst layer is stopped, and then the oxygen-containing It is preferable that they are 3 second-60 second per cycle until starting supply of gas. The time for stopping the supply of the oxygen-containing gas to the catalyst layer is preferably within 30% of the time per cycle from the viewpoint of restoring the catalyst activity and increasing the production efficiency of the hydrogen gas. For example, when one cycle is 10 seconds, one cycle is to supply the oxygen-containing gas for 7 seconds and to block the supply of the oxygen-containing gas for 3 seconds.

[Hydrogen Gas Separation Process]

In addition to hydrogen gas, the reaction gas obtained by the reaction gas manufacturing process contains impurity gases, such as steam of unreacted methanol, a carbon dioxide gas, carbon monoxide gas, and water vapor. In order to produce the hydrogen gas having high purity, the hydrogen gas contained in the reaction gas must be separated from the impurity gas. Therefore, in the hydrogen gas separation process, the hydrogen gas contained in the reaction gas is separated from the reaction gas obtained above. In the hydrogen gas separation process, a hydrogen gas separator 3 for separating hydrogen gas contained in the reaction gas from the reaction gas is used.

In the hydrogen gas manufacturing apparatus shown in FIG. 1, the hydrogen gas separator 3 is connected to the reaction gas producer 2 via the pipes 14 and 15. Although the heat exchanger 8 is provided between the pipe 14 and the pipe 15, it does not necessarily need to be provided. However, in the case where the heat exchanger 8 is provided, as described above, the heat exchanger 8 causes the reaction gas obtained in the reaction gas manufacturer 2 to react with the methanol and water of the raw material to exchange the methanol and water. Water can be heated efficiently, and the reaction gas can be cooled efficiently by heat-exchanging with methanol and water.

As the hydrogen gas separator 3, for example, an adsorption tower filled with an adsorbent may be mentioned. Although only one adsorption tower may be used, it is preferable to use a plurality of, for example, about 2 to 5 pieces from the viewpoint of efficiently producing hydrogen gas having high purity.

Examples of the adsorbent include carbon-based adsorbents for removing carbon dioxide and methanol, zeolites for removing carbon monoxide, and alumina for removing water vapor. The present invention is not limited only to this example. Usually, it is preferable to mix and use these adsorbents in order to remove by adsorbing impurity gases, such as vapor of unreacted methanol, carbon dioxide gas, carbon monoxide gas, and water vapor.

More specifically, the hydrogen gas separation step can be carried out in accordance with, for example, the separation method of the target gas described in JP-A-2004-66125.

In the hydrogen gas manufacturing apparatus shown in FIG. 1, the hydrogen gas having high purity obtained in the hydrogen gas separation step is stored in the hydrogen gas storage tank 17 through the pipe 16, but, for example, the obtained high purity hydrogen gas In the case of quickly using in the field, the hydrogen gas storage tank 17 is not necessary.

On the other hand, the impurity gas adsorbed and removed in the hydrogen gas separator 3 remains in the hydrogen gas separator 3 by, for example, degassing the hydrogen gas separator 3 after stopping the production of the hydrogen gas. It can be recovered as a gas. The remaining gas contains hydrogen gas in addition to the impurity gas. The remaining gas is sent to the gas combustion device 9 provided in the heat storage container 4 via the pipe 18.

[Residual Gas Combustion Process]

In the remaining gas combustion process, the remaining gas is burned. In the residual gas combustion process, the heat storage container 4 which has the gas combustion apparatus 9 for combusting the residual gas from which hydrogen gas was isolate | separated from the reaction gas is used.

In the present invention, the remaining gas is not disposed as a waste gas or burned, but as described above, the gas is burned by the gas combustion device 9 provided in the heat storage container 4 so as to effectively utilize the remaining gas. There is a big feature.

In the present invention, since the heat generated when burning the remaining gas by the gas combustion device 9 in the heat storage container 4 is provided so as to be transmitted to the source gas maker 1 and the reactive gas maker 2, Since methanol and water are heated and vaporized using the heat of combustion of residual gas, source gas can be manufactured efficiently. Moreover, in the series of reactions in the reaction gas maker 2, that is, the reactions represented by the reaction formulas (2) to (4), due to the heat of combustion of the remaining gas, the temperature in the reaction gas maker 2 due to the endothermic reaction decreases. Since is suppressed, hydrogen gas can be produced efficiently. In addition, since the source gas maker 1 and the reactive gas maker 2 are housed in the heat storage container 4, the hydrogen gas production apparatus itself of this invention can be miniaturized.

It is preferable to use a catalyst when burning the remaining gas by the gas combustion device 9. Among the catalysts, platinum catalysts are preferred in view of high catalyst activity and excellent heat resistance. The platinum catalyst may be platinum particles, or may be one in which platinum is supported on a single substance such as alumina particles, or one that has a honeycomb structure.

When burning residual gas, it is preferable to use air in order to burn residual gas. As shown in FIG. 1, air can be sent to the air heater 20 by the air blower 19, and can be sent to the gas combustor 9 through the piping 21. As shown in FIG.

The amount of air may be an amount in which hydrogen gas contained in the remaining gas is sufficiently burned, and is not particularly limited. Since the temperature of the combustion gas generated by burning the remaining gas can be controlled by this air amount, the temperature of the combustion gas can be adjusted by controlling the air amount. The temperature of the combustion gas can also be adjusted by introducing air into the generated combustion gas.

The temperature of the combustion gas is preferably 400 ° C. or more from the viewpoint of sufficiently heating the reaction gas maker 2, and preferably 800 ° C. or less from the viewpoint of preventing the reaction gas maker 2 from overheating.

The raw material gas maker 1 and the reactive gas maker 2 may send a combustion gas into the heat storage container 4, and may be heated by this fed combustion gas, and the raw material gas maker 1 and the reactive gas maker ( 2) is brought into contact with the gas combustion device 9 provided in the heat storage container 4, or provided near the gas combustion device 9, so that the remaining gas is burned in the gas combustion device 9. You may make it heat with the heat of combustion which generate | occur | produces.

When heating the source gas maker 1 and the reactive gas maker 2 by sending a combustion gas into the heat storage container 4, even if the inside of the heat storage container 4 is made into a closed space, the combustion gas may be filled in the said space. good.

In the embodiment shown in FIG. 1, the gas combustion device 9 is provided in the heat storage container 4. However, in the present invention, not only the embodiment shown in FIG. 1 but also the heat storage container 4 as shown in FIG. 2. As a part of the heat storage container 4, the separate chamber 4a which the internal space communicates with may be provided, and the gas combustor 9 may be provided in this separate chamber 4a. In addition, as shown in FIG. 2, the partition wall 22 may be provided between the source gas producer 1 and the reactive gas producer 2 as necessary.

The heating temperature of the source gas producer 1 due to the combustion heat generated when burning the residual gas is preferably 300 ° C. or higher from the viewpoint of sufficiently evaporating the source gas, taking into account the heat resistance of the source gas maker 1, and the like. Preferably, it is 1000 degrees C or less. Further, the heating temperature of the reaction gas maker 2 due to the combustion heat generated when burning the residual gas is preferably 250 ° C or higher from the viewpoint of reducing the amount of unreacted methanol to increase the amount of hydrogen gas generated. In view of suppressing deterioration of the catalyst, the temperature is preferably 600 ° C or lower.

In the gas combustion apparatus, a combustion catalyst can be used. Examples of the combustion catalyst include noble metals such as platinum, palladium, ruthenium, rhodium, silver, compounds of these metals, and the like, but the present invention is not limited only to these examples. The combustion catalyst can be used, for example, by adhering to a metal honeycomb, a ceramic honeycomb, a ball pallet, or the like.

As described above, according to the present invention, the raw material gas maker 1 and the reactive gas maker 2 are installed in the heat storage container 4 by the heat of combustion generated when burning the residual gas in the remaining gas combustion process. Therefore, since gas and methanol can be efficiently vaporized, raw gas can be efficiently produced, and hydrogen gas can be efficiently converted from methanol of raw material in that the raw material gas and oxygen-containing gas can be efficiently reacted. It can be prepared by.

(Example)

Next, the present invention will be described in more detail based on Examples, but the present invention is not limited to these Examples.

Example 1

The same hydrogen gas production apparatus as that used for the hydrogen gas production apparatus shown in FIG. 1 was used.

1. Raw material gas manufacturing process

Methanol and water were vaporized by heating methanol and water at 150-300 degreeC using the source gas maker for manufacturing source gas by vaporizing methanol and water, and source gas was manufactured.

2. Reaction gas manufacturing process

A reaction gas is produced by reacting the source gas and the oxygen-containing gas using a reaction gas maker for connecting the source gas maker and reacting the source gas and the oxygen-containing gas obtained in the source gas maker and producing a reaction gas. did.

More specifically, the reaction gas maker consists of the following two parts. First, an internal diameter 8.5 cm filled with a catalyst (Sigma Aldrich Japan Co., Ltd. product, copper oxide / alumina catalyst) is placed in an upstream side of the reaction gas maker and mainly undergoes an oxidation reaction represented by the reaction formula (1). And a reaction tube having a length of 20 cm. Moreover, in the reforming reaction part which is located downstream of the reaction gas maker and mainly reacts represented by Reaction formula (2)-(4), the cylindrical tube which has an inner diameter of 14 cm and a length of 95 cm, an inner diameter of 21 cm, and a length of 95 cm Cylindrical tubes having s overlapped with each other, and a reaction tube filled with the catalyst in the pores (equivalent diameter: 6.9 cm) between the two was used. The reaction gas was manufactured using this reaction gas maker.

In the reaction gas maker, the source gas and air obtained in the source gas production process were vented to have a flow rate of 259 g / min of methanol vapor, 220 g / min of steam, and 102 N liter / min of air (average value). More specifically, after the air was vented for 108 seconds at a flow rate of 113 N liter / minute, the operation of stopping the air passage for 12 seconds was periodically repeated. When the source gas and air were aerated, the molar ratio of water / methanol was 1.5 / 1 and the molar ratio of oxygen gas / methanol was 0.12 / 1.

Moreover, the linear velocity of the reaction gas in the oxidation reaction part of the reaction gas machine was 1.6 m / sec, the residence time was 0.12 sec, the linear velocity in the reforming reaction part of the reactant gas machine was 0.48 m / sec, and the residence time was 2.0. It was elderly.

As shown in FIG. 1, the reforming reaction part of the reaction gas maker was placed in a heat storage container, and the heat storage container was preheated to 270 ° C by an electric heater prior to the reaction.

This methanol water is passed through a source gas maker to form a vapor, and when combined with air and vented to an oxidation reaction unit of a reaction gas maker, a partial oxidation reaction starts rapidly, and the maximum temperature is 391 at a position of 7 cm from the top of the catalyst. ° C. The reaction gas discharged from this oxidation reaction part was sent to a reforming reaction part, and the reforming reaction was performed. After condensing the water contained in the gas from the reforming reactor and analyzing the gas phase by gas chromatography, 64.9% by volume of hydrogen gas, 1.2% by volume of carbon monoxide gas, 0.4% by volume of dimethylether gas, 22.8% by volume of carbon dioxide gas, and nitrogen 10.8% by volume of gas was included. On the other hand, unreacted methanol was not detected in the condensed water.

From the above results, it can be seen that hydrogen gas of 0.054 Nm 3 (2.4 mol) is obtained from 1 mol of methanol.

3. Hydrogen Gas Separation Process

Hydrogen gas contained in the reaction gas from the reaction gas, using a hydrogen gas separator connected to the reaction gas producer and separating hydrogen gas contained in the reaction gas from the reaction gas obtained in the reaction gas manufacturer. Separated.

More specifically, the zeolite molecular (Ca5A type) and carbon molecular (CMS) as the adsorbent are removed from the reactant gas after the moisture generated from the reactant gas obtained by the reaction gas maker is condensed. By passing through a three column type hydrogen gas separator (manufactured by Sumitomo Chemical Co., Ltd.) filled in a total volume of 50 liters at a volume ratio of, hydrogen gas having a purity of 99% was obtained at a rate of 22.5 Nm 3 / hour. This shows that 0.046 Nm <3> (2.07 mol) of hydrogen gas are obtained from 1 mol of methanol.

4. Residual Gas Combustion Process

The remaining gas from which the hydrogen gas was separated from the reaction gas was connected to the hydrogen gas separator by using a heat storage vessel having a gas combustion device for burning the remaining gas from which hydrogen gas was separated from the reaction gas in the hydrogen gas separator. Burned out.

More specifically, in the hydrogen gas separator, the remaining gas and air from which the hydrogen gas is separated from the reaction gas are mixed at a flow rate of 18 Nm 3 / hour of residual gas and 108 Nm 3 / hour of air, and the obtained mixed gas is mixed into the platinum catalyst layer. The gas was burned through to produce a heating gas having a temperature of 517 ° C.

The methanol evaporator and the reactor were heated with the heating gas generated above. The temperature at the reforming part of the reactor was 270 ° C and the temperature when the heating gas was discharged from the heat storage vessel was 281 ° C.

Example 2

The same operation as in Example 1 was carried out except that a catalyst (manufactured by Sud-Chemie Catalysts Japan, copper oxide / zinc oxide / alumina catalyst) was used instead of the catalyst used in the reforming reaction unit of the reaction gas maker of Example 1. As a result, after condensing the water of the gas discharged from the reforming reaction part of the reaction gas maker, the gas phase was analyzed by gas chromatography. As a result, 65.7% by volume of hydrogen gas, 1.0% by volume of carbon monoxide gas, and dimethylether gas were estimated from the temperature. 0.1% by volume, 23.0% by volume of carbon dioxide gas, and 10.2% by volume of nitrogen gas. On the other hand, unreacted methanol was not detected in the condensed water.

From this, it was confirmed that 0.058 Nm3 (2.6 mol) of hydrogen gas were produced from 1 mol of methanol. The reaction gas after this water was removed by condensation was passed through a three tower hydrogen gas separator (manufactured by Sumitomo Chemical Co., Ltd.) to obtain hydrogen gas having a purity of 99.9% at a rate of 23 Nm 3 / hour. From this result, it was confirmed that 0.047 Nm <3> (2.12 mol) of hydrogen gas were obtained from 1 mol of methanol.

Example 3

It carried out similarly to Example 1 except having used the catalyst (Sigma Aldrich Japan Co., Ltd. product, copper oxide / alumina catalyst) of 95 cm in length and 14 cm in inner diameter as a reforming reaction part of a reaction gas maker. The residence time of the reaction gas in the reforming reaction part of the reaction gas maker is expressed as:

[Retention time of reaction gas]

= [Volume in reaction gas machine] ÷ [volume in standard state of reaction gas introduced in unit time]

Based on the calculation, it was 1.6 seconds. After condensing and removing moisture from the gas from the reforming reaction unit of the reaction gas maker, the gas phase was analyzed by gas chromatography. As a result, 65.6 vol% of hydrogen gas, 1.0 vol% of carbon monoxide gas, 0.3 vol% of dimethyl ether gas, and 22.8 carbon dioxide gas were analyzed. % By volume and 10.3% by nitrogen gas were included. On the other hand, the condensed water contained 6.7 mass% of unreacted methanol. This shows that 0.057 Nm3 hydrogen gas is obtained from 1 mol of methanol.

The reaction gas after this water was removed by condensation was passed through a three tower hydrogen gas separator (manufactured by Sumitomo Chemical Co., Ltd.) to obtain hydrogen gas having a purity of 99% at a rate of 21.5 Nm 3 / hour. From this, it was confirmed that 0.044 Nm <3> (1.97 mol) of hydrogen gas were obtained from 1 mol of methanol.

Comparative Example 1

For the purpose of supplying heat to the reforming reaction unit by exothermic heat of the oxidation reaction, a double-gas return type reaction gas maker was used in which the inner cylinder was the oxidation reaction unit and the outer cylinder was the reforming reaction unit. The reaction tube of 38 cm in length, 8.5 cm in inner diameter, 70 cm in length and 7.4 cm in equivalent diameter was used for the oxidation reaction portion of the inner cylinder, and the remaining gas after the separation of hydrogen gas was applied to methanol and water. The reaction was carried out in the same manner as in Example 1 except that the supply of vaporization heat was mainly burned. After condensing the water contained in the gas from the reforming reaction unit of the reaction gas maker, the gas phase was analyzed by gas chromatography. As a result, 63.8 vol% of hydrogen gas, 1.5 vol% of carbon monoxide gas, 0.1 vol% of dimethyl ether gas, and carbon dioxide 22.3% gas and 12.3% nitrogen gas were included. On the other hand, the condensed water contained 17.6 mass% of unreacted methanol. This shows that 0.049 Nm <3> (2.2 mol) of hydrogen gas is obtained from 1 mol of methanol.

In Comparative Example 1, the reaction rate was lowered compared to Example 3, and it was confirmed that the amount of unreacted methanol was increased.

As a result, according to each example, it is understood that the energy efficiency is excellent, the hydrogen gas can be efficiently produced and can be applied to the miniaturized hydrogen gas production apparatus.

1: source gas maker 2: reactive gas maker
3: hydrogen gas separator 4: heat storage container
9: gas combustion device

Claims (5)

A hydrogen gas producing apparatus for producing hydrogen gas from methanol,
A raw material gas maker for producing a raw material gas by vaporizing methanol and water,
A reactive gas producer connected to the raw material gas maker, for reacting a raw material gas obtained in the raw material gas maker with an oxygen-containing gas to produce a reactive gas;
A hydrogen gas separator connected to the reactive gas producer for separating hydrogen gas contained in the reactive gas from the reactive gas obtained by the reactive gas producer, and
A heat retention container connected to the hydrogen gas separator and having a gas combustion device for burning residual gas from which hydrogen gas is separated from a reaction gas in the hydrogen gas separator.
Equipped with
The source gas maker and the reactive gas maker are installed in the heat storage container such that heat generated by burning residual gas in the gas combustion device is transferred. A hydrogen gas production method for producing hydrogen gas from methanol,
A raw material gas manufacturing step of producing a raw material gas by vaporizing methanol and water;
A reaction gas production process for producing a reaction gas by reacting the source gas with an oxygen-containing gas;
A hydrogen gas separation process for separating hydrogen gas contained in the reaction gas from the reaction gas, and
Residual gas combustion process of burning residual gas from which hydrogen gas was isolate | separated from the said reaction gas
Including;
Hydrogen characterized by vaporizing methanol and water in the raw material gas production step by heat generated when burning the residual gas in the residual gas combustion step, and reacting the raw material gas and the oxygen-containing gas in the reactive gas production step. Gas production method. The hydrogen gas production method according to claim 2, wherein in the reaction gas production process, the supply of the oxygen-containing gas is stopped regularly. The hydrogen gas production method according to claim 2 or 3, wherein in the remaining gas combustion step, the remaining gas is mixed after the remaining gas is mixed with the oxygen-containing gas. The hydrogen gas production method according to claim 2 or 3, wherein in the residual gas combustion step, the remaining gas is burned in the presence of a platinum catalyst.

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