WO2020100462A1

WO2020100462A1 - Multiple cylindrical type reformer and hydrogen production apparatus

Info

Publication number: WO2020100462A1
Application number: PCT/JP2019/039388
Authority: WO
Inventors: 晃平江口; 拓人櫛; 広基飯沼
Original assignee: 東京瓦斯株式会社
Priority date: 2018-11-12
Filing date: 2019-10-04
Publication date: 2020-05-22
Also published as: JP6553272B1; JP2020079177A

Abstract

Provided is a multiple cylindrical type reformer provided with: a raw material flow path having a preheating part in which mixed gas is obtained by heating water and a hydrocarbon supplied from one end side and a reforming part which is formed on the downstream side of the preheating part and in which a primary reformed gas containing hydrogen and carbon monoxide is generated by performing steam reforming on the mixed gas; and an exhaust gas flow path which is disposed adjacent to the inside of the raw material flow path and through which a combustion exhaust gas obtained by burning a fuel gas flows; and a carbon monoxide removal flow path which is disposed adjacent to the outside of the raw material flow path and which has provided thereto only a shift reaction part disposed in the whole area of the outside of the preheating part and generating a secondary reformed gas obtained by converting, to carbon dioxide and hydrogen, carbon monoxide and water contained in the primary reformed gas through water shift reaction.

Description

Multiple cylinder reformer and hydrogen production device

The present disclosure relates to a multi-cylinder reformer and a hydrogen production device.

2. Description of the Related Art Conventionally, as a hydrogen production device for obtaining hydrogen, it is known that a raw material hydrocarbon is reformed into a reformed gas by a steam reforming device and then supplied to a PSA (Pressure Swing Adsorption) device (hydrogen purifier). ing.

By the way, a multi-cylinder type reformer has been proposed as a steam reforming device (for example, refer to Patent Document 1). In this multi-tubular reformer, concentric cylindrical walls are multiply arranged, and the space between adjacent cylindrical walls or the inside of the innermost cylindrical wall is used as a flow path.

Specifically, between the second and third cylindrical walls, the preheating flow path in which the hydrocarbon gas, which is the raw material supplied from one end, and water are preheated and mixed to form a mixed gas, and the preheating A reforming catalyst layer for steam reforming the mixed gas is provided on the downstream side of the flow path. A combustion exhaust gas passage through which the combustion exhaust gas discharged from the combustion chamber flows is formed between the inner side, that is, between the first and second cylindrical walls. On the other hand, the outside, that is, between the third and fourth cylindrical walls, is a carbon monoxide removal passage for removing carbon monoxide from the primary reformed gas reformed by the reforming catalyst layer, and the preheating is performed. A shift reaction part for converting carbon monoxide in the primary reformed gas into carbon dioxide by an aqueous shift reaction on the outside of the flow path, and an oxidation part for converting carbon monoxide in the primary reformed gas into carbon dioxide by an oxidation reaction, Are arranged.

With such a configuration, the hydrocarbon gas and water supplied to the preheating passage are heat-exchanged with the combustion exhaust gas flowing through the combustion exhaust gas passage, that is, heated by the combustion exhaust gas, and the carbon monoxide removal passage It is heated by heat exchange with the reformed gas that undergoes the aqueous shift reaction in the shift reaction section and the reformed gas that undergoes the oxidation reaction in the oxidation section, and is efficiently made into a mixed gas.

Further, in this hydrogen production device, in the reformer, carbon monoxide is surely removed from the primary reformed gas by the aqueous shift reaction and the oxidation reaction, for example, it is converted into carbon dioxide to generate the secondary reformed gas. It is said that carbon monoxide, which is difficult to remove in the hydrogen purifier, can be removed or reduced from the primary reformed gas, and the hydrogen purity of the product hydrogen can be improved.

In the conventional technique described in Japanese Patent Laid-Open No. 2017-88490, carbon monoxide in the primary reformed gas is reduced by causing an aqueous shift reaction in the primary reformed gas in the shift reaction section, and air is further generated in the oxidation section. The carbon monoxide in the primary reformed gas was further reduced by reacting with the primary reformed gas to oxidize carbon monoxide into carbon dioxide.

This is excellent in removing carbon monoxide in the primary reformed gas, but since air is introduced in the oxidation part to oxidize carbon monoxide, the argon contained in the air is secondary. Mix in reformed gas. Since it is not easy to remove this argon from the secondary reformed gas in the hydrogen purifier on the downstream side, there is a problem that the purity of hydrogen produced is reduced.

On the other hand, in the multi-cylinder type reformer, there is a problem that the amount of heating for the preheating part is reduced only by removing the oxidation part from the carbon monoxide removal passage.

The present disclosure provides a multi-cylinder reformer that prevents or suppresses the mixing of argon with the reformed gas while ensuring a heating amount for the preheating unit, and a hydrogen production device with improved hydrogen purity of product hydrogen.

A first aspect of the present disclosure is that hydrocarbon and water are supplied as raw materials, and a primary reformed gas containing hydrogen as a main component is produced by steam-reforming a mixture of hydrocarbon and steam, A multi-cylinder reformer for producing a secondary reformed gas in which carbon monoxide is reduced from the primary reformed gas, wherein hydrocarbon and water supplied from one end side are heated to form a mixed gas And a reforming section that is formed on the downstream side of the preheating section and that generates a primary reformed gas containing hydrogen and carbon monoxide by steam reforming the mixed gas. And an exhaust gas passage disposed adjacent to the inside of the raw material passage and flowing a combustion exhaust gas obtained by burning a fuel gas, and disposed outside of the raw material passage, outside the preheating unit. Carbon monoxide disposed in the entire region and provided only with a shift reaction part for converting water and carbon monoxide contained in the primary reformed gas into carbon dioxide and hydrogen by an aqueous shift reaction to generate the secondary reformed gas And a removal flow path.

In this multi-cylinder reformer, the raw material hydrocarbons and water are supplied. Hydrocarbon and water are heated in the preheating section of the multi-cylinder reformer to form a mixed gas, and the reformed section steam-reforms the mixed gas to generate a primary reformed gas containing hydrogen as a main component. It

In the primary reformed gas that has been steam-reformed in the reforming section, water and carbon monoxide contained in the shift reaction section of the carbon monoxide removal channel are converted into hydrogen and carbon dioxide by the aqueous shift reaction. That is, a secondary reformed gas in which carbon monoxide is reduced is generated from the primary reformed gas in the shift reaction section.

By the way, only the shift reaction part is provided in the carbon monoxide removal flow path. That is, when removing or reducing carbon monoxide from the primary reformed gas, since only the aqueous shift reaction is used, air is not mixed into the secondary reformed gas. That is, the multi-cylinder reformer can generate the secondary reformed gas in which the mixing of argon is prevented.

Therefore, when hydrogen is produced by incorporating this multi-cylinder reformer into a hydrogen production apparatus and purifying the secondary reformed gas produced by the multi-cylinder reformer with a hydrogen purifier, Since the secondary reformed gas, which is difficult to remove in the reactor by mixing in air with argon, is supplied to the hydrogen purifier, the hydrogen purity of the product hydrogen can be improved.

On the other hand, in the multi-tubular reformer, the shift reaction part is provided in the entire area outside the preheating part of the carbon monoxide removal flow path located outside the raw material flow path, so that the exhaust gas flow path inside the preheating part flows. The raw material water is sufficiently heated by the heat of the combustion exhaust gas and the heat of reaction due to the aqueous shift reaction in the shift reaction section provided all over the outside of the preheating section to form steam, and a mixed gas is satisfactorily generated. The steam reforming reaction in the reformer is promoted.

According to a second aspect of the present disclosure, in the first aspect, a combustion chamber in which a burner for burning the fuel gas is arranged is formed inside the exhaust gas passage of the multi-cylinder reformer. The tip of the nozzle of the burner may be located inside the reforming section.

The tip of the nozzle of the burner arranged in the combustion chamber of the multi-tubular reformer is located inside the reforming section. Therefore, when a flame is formed from the tip of the nozzle by supplying the fuel gas to the burner, the flame of the burner is located inside the reforming section of the multi-cylinder reformer. As a result, the amount of heat supplied to the reforming section is increased, and the steam reforming reaction, which is an endothermic reaction in the reforming section, is further promoted.

A third aspect of the present disclosure is connected to the multi-cylinder reformer of the second or third aspect of the present disclosure, and the multi-cylinder reformer to convert the secondary reformed gas into product hydrogen and impurities. And a hydrogen purifier that purifies the product hydrogen by separating into hydrogen and hydrogen.

In this hydrogen production device, the raw material hydrocarbons and water are supplied to the multi-cylinder reformer. Hydrocarbon and water are heated in the preheating section of the multi-cylinder reformer to form a mixed gas, and the reformed section steam-reforms the mixed gas to generate a primary reformed gas containing hydrogen as a main component. It

By the way, only the shift reaction part is provided in the carbon monoxide removal flow path. That is, when removing or reducing carbon monoxide from the primary reformed gas, since only the aqueous shift reaction is used, air is not mixed into the secondary reformed gas. Therefore, since the secondary reformed gas, which is difficult to remove in the hydrogen purifier and in which air is not mixed with argon, is supplied to the hydrogen purifier, the hydrogen purity of the product hydrogen can be improved.

According to the first aspect, the multi-cylinder reformer of the present disclosure can prevent the secondary reformed gas from being mixed with argon while securing a heating amount for the preheating portion of the reformer.

According to the second aspect, in the multi-cylinder reformer of the present disclosure, the heat supply amount to the reforming section is increased, and the steam reforming reaction in the reforming section is further promoted.

According to the third aspect, the hydrogen production device of the present disclosure can improve the hydrogen purity of product hydrogen while ensuring the heating amount for the preheating part of the reformer.

1 is a schematic configuration diagram showing a hydrogen production device according to a first embodiment of the present disclosure. FIG. 3 is a cross-sectional view showing a multi-tube reformer according to the first embodiment of the present disclosure. FIG. 6 is a cross-sectional view showing a multi-tube reformer according to a second embodiment of the present disclosure.

[First Embodiment]
An example of the multi-cylinder reformer and the hydrogen production device according to the first embodiment of the present disclosure will be described with reference to FIGS. 1 and 2.

<Hydrogen production equipment>
As shown in FIG. 1, the hydrogen production apparatus 10 includes a multi-cylinder reformer (hereinafter, also referred to as a “reformer”) 12 that generates a reformed gas obtained by steam reforming hydrocarbons, for example, city gas. A compressor 80 for compressing the reformed gas, and a hydrogen purifier 90 for purifying hydrogen gas by removing impurities from the compressed reformed gas. Further, the hydrogen production device 10 includes a pre-pressurization water separation unit 50, a post-pressurization water separation unit 60, which separates and removes water from the reformed gas on the upstream side and the downstream side of the compressor 80, respectively, and the reformer 12 to be described later. And a combustion exhaust gas water separation unit 70 for separating and removing water from the combustion exhaust gas.

The hydrogen production device 10 produces hydrogen from a hydrocarbon raw material, and in the present embodiment, a case where city gas containing methane as a main component is used as an example of the hydrocarbon raw material will be described.

(Multiple cylinder reformer)
As shown in FIG. 2, the multi-tubular reformer 12 has a plurality of

tubular walls

21, 22, 23, 24 (hereinafter, may be referred to as “cylindrical walls 21-24”) arranged in multiple layers. Have The plurality of cylindrical walls 21 to 24 are formed in, for example, a cylindrical shape or an elliptic cylindrical shape. A combustion chamber 25 is formed inside the first cylindrical wall 21 from the inner side among the plurality of cylindrical walls 21 to 24, and a burner 26 is arranged downward on the combustion chamber 25. There is.

Further, an air supply pipe 40 for supplying combustion air from the outside is connected to the upper end of the combustion chamber 25. A raw material branch pipe 33A branched from a raw material supply pipe 33 for further supplying city gas is connected to the burner 26. An air branch pipe 40A branched from the air supply pipe 40 is connected to the raw material branch pipe 33A. Also. An offgas recirculation pipe 100 is connected to the burner 26. Therefore, the burner 26 is configured to be supplied with gas in which city gas is mixed with air or off gas. The gas in which city gas is mixed with air or the off gas corresponds to the “fuel gas”.

A combustion exhaust gas passage 27 is formed between the first tubular wall 21 and the second tubular wall 22. A lower end portion of the combustion exhaust gas passage 27 communicates with the combustion chamber 25, and a gas exhaust pipe 28 for exhausting gas is connected to an upper end portion of the combustion exhaust gas passage 27. The combustion exhaust gas discharged from the combustion chamber 25 flows from the lower side to the upper side in the combustion exhaust gas flow path 27 and is sent to the combustion exhaust gas water separation unit 70 through the gas discharge pipe 28. The combustion exhaust gas passage 27 corresponds to the “exhaust gas passage”.

Also, a first flow path 31 is formed between the second tubular wall 22 and the third tubular wall 23. An upper portion of the first flow passage 31 is formed as a preheating flow passage 32, and a raw material supply pipe 33 for supplying city gas and reforming water are supplied to an upper end portion of the preheating flow passage 32. Is connected to the reforming water supply pipe 34. Further, a spiral member 35 is provided between the second cylindrical wall 22 and the third cylindrical wall 23, and the preheating flow passage 32 is formed in a spiral shape by the spiral member 35. There is. The first flow path 31 corresponds to the “raw material flow path”. Further, the preheating flow path 32 corresponds to the “preheating section”.

The combustion exhaust gas passage 27 and the preheating passage 32 are formed over the entire circumference in the circumferential direction of the multi-cylinder reformer 12, and the axial range A (see FIG. 2) of the preheating passage 32 is , The range from the upper end of the reforming catalyst layer 36 to the upper end of the first flow path 31.

The city gas can be supplied to the preheating channel 32 from the raw material supply pipe 33, and further the reforming water can be supplied from the reforming water supply pipe 34. The city gas and the reforming water flow from the upper side to the lower side in the preheating flow channel 32, are heat-exchanged with the combustion exhaust gas through the second tubular wall 22, and will be described later through the third tubular wall 23. The water is vaporized by heat exchange with the reformed gas G0 which has undergone the aqueous shift reaction in the CO shift catalyst layer 45. In the preheating flow path 32, the mixed gas is generated by mixing the city gas and the reforming water in the vapor phase, that is, steam.

A reforming catalyst layer 36 is provided below the preheating channel 32 in the first channel 31, and the mixed gas generated in the preheating channel 32 is supplied to the reforming catalyst layer 36. It is a configuration. The reforming catalyst layer 36 receives heat from the combustion exhaust gas flowing through the combustion exhaust gas passage 27 and undergoes a steam reforming reaction which is an endothermic reaction of the mixed gas to generate a reformed gas G0 containing hydrogen as a main component. It is a configuration. The reforming catalyst layer 36 corresponds to the “reforming section”. Further, the reformed gas G0 corresponds to the “primary reformed gas”.

Furthermore, a second flow path 42 is formed between the third cylindrical wall 23 and the fourth cylindrical wall 24. The lower end of the second flow path 42 communicates with the lower end of the first flow path 31. A lower portion of the second flow passage 42 is formed as a reformed gas flow passage 43, and a reformed gas discharge pipe 44 is connected to an upper end portion of the second flow passage 42. The second channel 42 corresponds to the "carbon monoxide removal channel".

Further, a CO shift catalyst layer 45 is provided above the reformed gas passage 43 in the second passage 42, and the reformed gas G0 generated in the reformed catalyst layer 36 is the reformed gas. After passing through the flow path 43, the CO shift catalyst layer 45 is supplied. In the CO conversion catalyst layer 45, carbon monoxide and water vapor contained in the reformed gas G0 are converted into hydrogen and carbon dioxide by an aqueous shift reaction, and the carbon monoxide in the reformed gas G0 is reduced, that is, can be reduced. ..

That is, only the CO shift catalyst layer 45 is disposed in the second flow path 42 as a means for reducing carbon monoxide from the reformed gas G0.

The reformed gas G1 in which carbon monoxide is reduced in the CO shift catalyst layer 45 is discharged through the reformed gas discharge pipe 44. The reformed gas G1 corresponds to the “secondary reformed gas”.

The CO shift catalyst layer 45 is disposed over the entire circumference in the circumferential direction of the multi-cylinder reformer 12, and is located outside the preheating passage 32 in the axial direction (see the arrow X direction in FIG. 2). It is arranged in the entire area, that is, in the axial range B).

Here, “the CO conversion catalyst layer 45 is arranged all over the outside of the preheating channel 32” means the surface area of the CO conversion catalyst layer 45 occupying the tubular wall 23 with respect to the surface area of the preheating channel 32 occupying the tubular wall 23. This means that the ratio, that is, the ratio of the axial range B to the axial range A of the preheating channel 32 is 70% or more and 100% or less.
The ratio of the surface area of the CO shift catalyst layer 45 in the tubular wall 23 to the surface area of the preheating channel 32 in the tubular wall 23, that is, the ratio of the axial range B to the axial range A in the preheating channel 32 is , Preferably 80% or more and 100% or less, more preferably 90% or more and 100% or less.

As shown in FIG. 1, the reformed gas G1 generated in the multi-cylinder reformer 12 passes through the pre-pressurization water separation unit 50, the compressor 80, the post-pressurization water separation unit 60, and the hydrogen purifier 90 in this order. Flowing in. That is, in the gas flow direction, from the upstream side to the downstream side, the multi-tubular reformer 12, the pre-pressurization water separation unit 50, the compressor 80, the post-pressurization water separation unit 60, and the hydrogen purifier 90 are arranged in this order. It is arranged.

(Pre-pressurization water separator)
The downstream end of a reformed gas discharge pipe 44, into which the reformed gas G1 flows from the multi-cylinder reformer 12, is connected to the pre-pressurization water separation unit 50. A water recovery pipe 59 is connected to the bottom of the pre-pressurization water separation unit 50, and a communication flow path pipe 56 is connected to the top of the pre-pressurization water separation unit 50. The reformed gas G1 is condensed and separated in the heat exchanger HE1 arranged in the reformed gas discharge pipe 44 upstream of the pre-pressurization water separation unit 50 by cooling by heat exchange with cooling water, and before the pressurization. Liquid phase water can be stored under the water separation unit 50. The liquid phase water is sent to the water recovery pipe 59. The reformed gas G2 after the water is condensed is sent to the communication flow path pipe 56.

(Compressor)
In the compressor 80, there are a communication flow passage pipe 56 through which the reformed gas G2 from the pre-pressurization water separation unit 50 flows, and a communication flow passage pipe 66 through which the reformed gas G2 supplied to the post-pressurization water separation unit 60 flows. It is connected. The compressor 80 is capable of compressing the reformed gas G2 supplied from the pre-pressurization water separation unit 50 and supplying it to the post-pressurization water separation unit 60.

(Water separation unit after pressurization)
To the post-pressurization water separation unit 60, a downstream end of a communication flow pipe 66 that allows the reformed gas G2 to flow from the compressor 80 is connected. A water recovery pipe 69 is connected to the bottom of the post-pressurization water separation unit 60, and a communication channel pipe 68 is connected to the top of the post-pressurization water separation unit 60. The reformed gas G2 is condensed and separated by cooling by heat exchange with cooling water in the heat exchanger HE2 arranged in the communication flow path pipe 66 upstream of the post-pressurization water separation section 60, and the post-pressurization water is separated. Liquid phase water can be stored in the lower portion of the separation unit 60. The liquid phase water is sent to the water recovery pipe 69. The reformed gas G3 after the water is condensed is sent to the communication flow path pipe 68.

(Hydrogen refiner)
The hydrogen purifier 90 is connected to the downstream end of the communication flow pipe 68 through which the reformed gas G3 from the post-pressurization water separation unit 60 flows and the upstream end of the offgas reflux pipe 100 through which the offgas of the hydrogen purifier 90 flows. ing.

As the hydrogen purifier 90, a PSA device is used as an example. The hydrogen purifier 90 includes a pair of adsorption tanks, one adsorption tank performs an adsorption step of adsorbing impurities on the adsorbent, and the other adsorption tank performs a desorption step of desorbing the impurities adsorbed on the adsorbent, Next, the desorption process is performed in one adsorption tank, and the adsorption process is performed in the other adsorption tank. By repeating this periodically, the reformed gas G3 is continuously separated into hydrogen and impurities containing carbon monoxide, that is, off-gas OG, and hydrogen is purified. The purified hydrogen is sent to the hydrogen supply pipe 92, can be stored in a tank (not shown), or can be sent to the hydrogen supply line.

The off gas of the hydrogen purifier 90 can be supplied to the burner 26 of the reformer 12 via the off gas reflux pipe 100.

(Off gas tank)
An offgas tank 102 is provided in the middle of an offgas recirculation pipe 100 that communicates with the burner 26 of the combustion chamber 25 of the reformer 12 from the hydrogen purifier 90. The off-gas sent from the hydrogen purifier 90 is temporarily stored in the off-gas tank 102, leveled in flow rate and composition, and supplied to the burner 26.

(Combustion exhaust gas water separation unit)
The downstream end of a gas exhaust pipe 28 that guides the combustion exhaust gas from the combustion exhaust gas flow path 27 of the reformer 12 is connected to the combustion exhaust gas water separation unit 70. A water recovery pipe 78 is connected to the bottom of the combustion exhaust gas water separation unit 70, and a gas discharge pipe 76 is connected to the upper portion of the combustion exhaust gas water separation unit 70. The combustion exhaust gas discharged from the combustion chamber 25 is separated and condensed in the heat exchanger HE3 arranged in the gas discharge pipe 28 upstream of the combustion exhaust gas water separation unit 70 by cooling by heat exchange with cooling water. The liquid water can be stored under the combustion exhaust gas water separation unit 70. The liquid phase water is sent to the water recovery pipe 78. The combustion exhaust gas after the water is condensed is discharged from the gas discharge pipe 76 into the outside air.

The downstream end of each of the

water recovery pipes

59, 69, 78 is connected to the reforming water supply pipe 34. The reforming water supply pipe 34 is provided with a water treatment device 34A made of an ion exchange resin for removing dissolved ion components. The external water supply unit 17 is connected to the reforming water supply pipe 34. For example, pure water or city water is supplied from the external water supply unit 17 to the reforming water supply pipe 34.

Further, the reforming water supply pipe 34 is provided with a pump P1. The water separated by the pre-pressurization water separation unit 50, the post-pressurization water separation unit 60, the combustion exhaust gas water separation unit 70, or the water supplied from the external water supply unit 17 is sent to the multi-tubular reformer 12 by the pump P1. It is a configuration to be supplied.

(Action)
Next, the operation of the hydrogen production device 10 and the multi-cylinder reformer 12 will be described.

City gas is supplied from the raw material supply pipe 33 to the multi-cylinder reformer 12. As shown in FIG. 2, the city gas supplied to the multi-cylinder reformer 12 is mixed with the reforming water in the pre-heating channel 32 of the multi-cylinder reformer 12 while being mixed with the reforming water. While exchanging heat with the combustion exhaust gas passing through the inner combustion exhaust gas passage 27, the CO shift catalyst layer 45 arranged in the second passage 42 outside the preheating passage 32 causes an aqueous shift reaction which is an exothermic reaction. Is exchanged with the reformed gas. That is, the city gas and the reforming water are heated while being mixed and supplied to the reforming catalyst layer 36.

In the reforming catalyst layer 36, the mixed gas receives the heat of the combustion exhaust gas flowing through the combustion exhaust gas passage 27 to cause a steam reforming reaction which is an endothermic reaction, and the reformed gas G0 containing hydrogen as a main component is generated. The reformed gas G0 is supplied to the CO shift catalyst layer 45 through the reformed gas passage 43. In the CO conversion catalyst layer 45, carbon monoxide contained in the reformed gas G0 reacts with steam to be converted into hydrogen and carbon dioxide, that is, an aqueous shift reaction is performed, and carbon monoxide is reduced.

The reformed gas G1 in which carbon monoxide is reduced in the CO shift catalyst layer 45 in this manner is sent to the reformed gas discharge pipe 44.

At this time, in the combustion chamber 25 of the multi-cylinder reformer 12, a gas obtained by mixing the city gas and air supplied from the raw material branch pipe 33A and the air branch pipe 40A, or the off gas supplied from the off gas recirculation pipe 100. Are burned by the burner 26. The combustion exhaust gas is supplied from the combustion chamber 25 to the combustion exhaust gas water separation unit 70 via the combustion exhaust gas flow passage 27 and the gas exhaust pipe 28. As shown in FIG. 1, the water contained in the combustion exhaust gas is cooled and condensed by heat exchange in the heat exchanger HE3, stored in the combustion exhaust gas water separation unit 70, and sent to the water recovery pipe 78. The combustion exhaust gas from which the water has been separated is discharged from the gas discharge pipe 76 into the outside air.

On the other hand, as shown in FIG. 1, the reformed gas G1 is supplied to the pre-pressurization water separation unit 50 via the reformed gas discharge pipe 44. In the pre-pressurization water separation unit 50, water condensed by cooling by heat exchange in the heat exchanger HE1 is stored and sent to the water recovery pipe 59. The reformed gas G2 from which the water has been separated is supplied to the compressor 80 from the communication flow path pipe 56 and is compressed by the compressor 80.

The compressed reformed gas G2 is supplied to the water separation unit 60 after pressurization from the communication flow pipe 66. In the post-pressurization water separation unit 60, water condensed by cooling by heat exchange in the heat exchanger HE2 is stored and sent to the water recovery pipe 69. The reformed gas G3 from which water has been separated is supplied to the hydrogen purifier 90 from the communication flow path pipe 68.

The water sent from the pre-pressurization water separation unit 50, the post-pressurization water separation unit 60, and the combustion exhaust gas water separation unit 70 to the

water recovery pipes

59, 69, and 78 is returned to the reforming water supply pipe 34. By driving the pump P1, the reforming water supply pipe 34 supplies the reforming water to the multi-cylinder reformer 12.

The hydrogen purifier 90 employs a pressure swing method, in which one of the pair of adsorption tanks adsorbs impurities other than hydrogen in the adsorbent and the other adsorption tank desorbs the impurities adsorbed in the adsorbent. .. In the hydrogen purifier 90, the adsorption step and the desorption step are repeated in each adsorption tank at a constant cycle to continuously separate hydrogen and impurities from the reformed gas G3 to purify hydrogen.

Hydrogen as a product purified by the hydrogen purifier 90 is sent to the hydrogen supply pipe 92 and stored in a tank (not shown) or sent to the hydrogen supply line.

On the other hand, the off-gas OG discharged from the hydrogen purifier 90 is temporarily stored in an off-gas tank 102 provided in the middle of the off-gas recirculation pipe 100, and then the flow rate and composition thereof are leveled to the burner 26 of the reformer 12. Supplied. The offgas OG contains carbon monoxide that could not be completely removed by the reformer 12 and hydrogen that could not be completely separated by the hydrogen purifier 90.

As described above, in the hydrogen production device 10, in order to remove carbon monoxide from the reformed gas G0 steam-reformed by the reforming catalyst layer 36 of the reformer 12, the CO shift catalyst layer 45, that is, the water shift. Only the reaction is used. That is, in the reformer 12, carbon monoxide is removed from the reformed gas G0 only by a reaction that does not use air, so that the reformed gas G1 delivered from the reformer 12 may contain argon. To be prevented.

Therefore, since the reformed gas G1, that is, the reformed gas G3 does not contain argon that is difficult to remove by the hydrogen purifier 90, the purity of the product hydrogen purified by the hydrogen purifier 90 can be improved. Alternatively, the removal of argon in the hydrogen purifier 90 prevents the load on the hydrogen purifier 90 from increasing.

On the other hand, in the reformer 12, the CO shift catalyst layer 45 is arranged all over the outside of the preheating flow channel 32. Here, the ratio of the surface area of the CO conversion catalyst layer 45 occupying the cylindrical wall 23 to the surface area of the preheating channel 32 occupying the cylindrical wall 23, that is, the CO conversion catalyst layer 45 occupying the axial range A of the preheating channel 32. The ratio of the axial range B is 70% or more and 100% or less. Therefore, a sufficient amount of heat is given to the water (steam) flowing through the preheating channel 32 and the hydrocarbon from the CO shift catalyst layer 45 in which the aqueous shift reaction, which is an exothermic reaction, is performed. ) And hydrocarbons can be heated sufficiently. That is, the CO shift catalyst layer 45 can supply a sufficient amount of heat to the water and steam and the hydrocarbons flowing through the preheating flow passage 32 together with the combustion exhaust gas flowing through the combustion exhaust gas flow passage 27. Therefore, the mixed gas can be satisfactorily generated.

Further, in the reformer 12, removal of carbon monoxide in the reformed gas G0, that is, conversion of carbon monoxide to carbon dioxide is all performed by the CO shift catalyst layer 45 (aqueous shift reaction). Therefore, in comparison with the case where the aqueous shift reaction and the oxidation reaction are used, the oxidation reaction portion is also replaced by the CO shift catalyst layer 45, that is, the water shift reaction portion, so that the production amount of product hydrogen increases.

Furthermore, since the CO conversion catalyst layer 45 is provided in the entire area outside the preheating flow path 32 in the second flow path 42, the axial length of the CO conversion catalyst layer 45, that is, the volume is sufficiently secured, and the space velocity ( SV) is reduced, and the load on the CO shift catalyst layer 45 is reduced.

Further, in the reformer 12, since only the CO shift catalyst layer 45 is used as a means for reducing carbon monoxide from the reformed gas G0, the structure of the reformer 12 is simplified.

[Second Embodiment]
An example of the multi-cylinder reformer and the hydrogen production device according to the second embodiment of the present disclosure will be described with reference to FIGS. 1 and 3. The same components as those in the first embodiment are designated by the same reference numerals, and detailed description thereof will be omitted. Further, the only difference from the first embodiment is the position of the burner in the multi-tubular reformer, so only the relevant portions will be described and other explanations will be omitted.

(Constitution)
As shown in FIG. 3, in the multi-cylinder reformer 202 of the hydrogen production apparatus 200, the axial length of the burner 204 arranged in the combustion chamber 25 is made longer than that of the burner 26 of the first embodiment. ing. That is, the burner 204 is arranged in the combustion chamber 25 so that the tip 206A of the nozzle 206 of the burner 204 is located inside the reforming catalyst layer 36.

(Action)
The hydrogen production apparatus 200 configured in this way has the same operation as the hydrogen production apparatus 10 of the first embodiment.

Further, the burner 204 of the multi-cylinder reformer 202 is supplied with a gas in which city gas is mixed with air or an off gas, so that the burner 204 is burned.

Here, as shown in FIG. 3, the nozzle 206 of the burner 204 is opened downward in the combustion chamber 25 of the multi-cylinder reformer 202. Further, the tip 206A of the nozzle 206 of the burner 204 is located inside the reforming catalyst layer 36.

Therefore, as shown in FIG. 3, the flame F formed at the tip 206A of the nozzle 206 of the burner 204 is formed downward and is located inside the reforming catalyst layer 36.

By the way, in the multi-cylinder reformer 202, a mixed gas generated from city gas and reforming water is supplied to the reforming catalyst layer 36 for steam reforming. This steam reforming reaction is an endothermic reaction. Is. Therefore, since the flame F formed by the burner 26 in the combustion chamber 25 is located inside the reforming catalyst layer 36, the heat supply amount to the reforming catalyst layer 36 increases, and the steam reforming in the reforming catalyst layer 36 increases. Is further promoted.

[Other]
In the hydrogen production device 10 according to the embodiment, the case where the hydrogen purifier 90 is a PSA device has been described, but the hydrogen purifier 90 is not limited to this as long as hydrogen can be purified from the reformed gas G3.

The disclosure of Japanese Patent Application 2018-212517 dated November 12, 2018 is incorporated herein by reference in its entirety.

All publications, patent applications, and technical standards mentioned herein are to the same extent as if each individual publication, patent application, and technical standard were specifically and individually noted to be incorporated by reference, Incorporated herein by reference.

Claims

Hydrocarbon and water are supplied as raw materials, and a primary reformed gas containing hydrogen as a main component is produced by steam reforming a mixture of hydrocarbon and steam, and carbon monoxide is produced from the primary reformed gas. A multi-cylinder type reformer that produces a secondary reformed gas with reduced
A preheating part in which hydrocarbon and water supplied from one end side are heated to form a mixed gas, and hydrogen and carbon monoxide are formed on the downstream side of the preheating part and the mixed gas is steam-reformed. A raw material flow path having a reforming section in which a primary reformed gas containing is generated,
An exhaust gas flow passage, which is disposed adjacent to the inside of the raw material flow passage and flows a combustion exhaust gas obtained by burning a fuel gas,
It is arranged adjacent to the outside of the raw material flow path, and is arranged all over the outside of the preheating section to convert water and carbon monoxide contained in the primary reformed gas into carbon dioxide and hydrogen by an aqueous shift reaction and A carbon monoxide removal flow path provided only with a shift reaction part for generating a secondary reformed gas,
Multiple cylinder type reformer equipped with.
A combustion chamber, in which a burner for burning the fuel gas is disposed, is formed inside the exhaust gas flow path of the multi-cylinder reformer, and a tip of a nozzle of the burner is inside the reforming section. The multi-tubular reformer according to claim 1, which is located at
A multi-cylinder reformer according to claim 1 or 2,
A hydrogen purifier that is connected to the multi-cylinder reformer and separates the secondary reformed gas into product hydrogen and impurities to purify product hydrogen,
Hydrogen production device equipped with.