JP6602941B1 - Hydrogen production apparatus and hydrogen production method - Google Patents

Abstract

To provide a hydrogen production apparatus and a hydrogen production method that prevent a reformed gas that has not reached a predetermined hydrogen concentration at the time of starting a reformer from being supplied to a hydrogen purifier and improve the thermal efficiency of the entire apparatus. provide. When a reformed gas in a reformer 12 does not reach a predetermined hydrogen concentration, a hydrogen production apparatus 10 closes a first on-off valve 102 and opens a second on-off valve 104. As a result, the reformed gas is supplied to the offgas tank 112, supplied to the burner 26 of the reformer 12 through the offgas recirculation pipe 110, and burned in the combustion chamber 25. As a result, the reformed gas that has not reached the predetermined hydrogen concentration is prevented from being supplied to the hydrogen purifier 90 and the purity of the product hydrogen is prevented from being lowered, and supplied to the burner 26 of the reformer 12 as fuel gas. As a result, the thermal efficiency of the entire hydrogen production apparatus is improved. [Selection] Figure 1

Description

  The present invention relates to a hydrogen production apparatus and a hydrogen production method, and more particularly to a hydrogen production apparatus and a hydrogen production method for producing hydrogen by reforming a hydrocarbon raw material.

  Conventionally, as a hydrogen production apparatus for obtaining hydrogen, a raw material hydrocarbon is reformed into reformed gas (steam) by a reformer and then supplied to a pressure swing adsorption (PSA) apparatus (hydrogen purifier). Are known. Hydrogen separated from impurities from the reformed gas by PSA is taken out.

  In the reformer, the hydrogen concentration or the like of the reformed gas steam-reformed from the raw material hydrocarbon may not reach a predetermined concentration. For example, when the reformer is started, the internal temperature of the reformer does not rise to a predetermined temperature, and the reformed gas subjected to steam reforming may not reach a predetermined hydrogen concentration (carbon monoxide concentration is high). . Therefore, in the hydrogen production apparatus of Patent Document 1, the reformed gas generated in the reformer that does not reach the predetermined hydrogen concentration is supplied to the flare. That is, by preventing the reformed gas generated in the reformer from reaching the predetermined hydrogen concentration from being supplied to the hydrogen purifier, product hydrogen that does not reach the predetermined quality is prevented from being produced.

JP 2009-149466 A

  The hydrogen production apparatus described in Patent Document 1 is excellent in terms of preventing production of product hydrogen that does not reach a predetermined quality, but there is room for improvement in terms of thermal efficiency of the hydrogen production apparatus.

  An object of the present invention is to provide a hydrogen production apparatus and a hydrogen production method in which reformed gas that has not reached a predetermined hydrogen concentration is prevented from being supplied to a hydrogen purifier and the thermal efficiency of the entire apparatus is improved. That is.

The hydrogen production apparatus according to claim 1 is a reformer that reforms hydrocarbon supplied as a raw material to generate a reformed gas containing hydrogen as a main component, and reforms the steam to reform the hydrocarbon. A reformer having a carbonaceous catalyst layer, and a carbon monoxide removal section for removing carbon monoxide from the reformed gas downstream of the reforming catalyst layer, and connected to the reformer, the reforming A hydrogen purifier that separates the gas into product hydrogen and an off-gas that is an impurity to purify the product hydrogen; an off-gas passage that returns the off-gas as fuel to the combustion chamber of the reformer from the hydrogen purifier; and the off-gas An offgas tank that is provided on a flow path and temporarily stores the offgas, and then supplies the reformer to the reformer, and a branch from a reformed gas flow path from the reformer to the hydrogen purifier. Reaching the reformed gas branch flow path and the reformed gas flow Switching means for communicating with either the upstream side of the branch position to the reformed gas branch flow path, the downstream side or the reformed gas branch flow path, and blocking the other, and the reformer A temperature detection unit that is disposed between the reforming catalyst layer and the carbon monoxide removal unit on the flow path through which the reformed gas flows, and that detects the temperature of the reformed gas, and is detected by the temperature detection unit. A controller for controlling the switching means based on the temperature of the reformed gas, a gas flow rate detecting means for detecting a gas flow rate provided downstream of the offgas tank in the offgas flow path, and the modified An air supply flow path for supplying air to the combustion chamber of the gasifier, and an air flow rate adjusting valve provided on the air supply flow path for adjusting the flow rate of air supplied to the combustion chamber, The temperature of the reformed gas and the gas flow rate detecting means In on the basis of the detected gas flow rate, adjusting the air flow the air flow control valve as a control.

  In this hydrogen production apparatus, if the internal temperature of the reformer does not reach a predetermined temperature, steam reforming is not sufficiently performed in the reformer, and a reformed gas that does not reach a predetermined hydrogen concentration is generated. .

The control unit determines whether or not the hydrogen concentration of the reformed gas has reached a predetermined concentration based on the temperature of the reformed gas detected by the temperature detecting means. For example, when the temperature of the reformed gas is less than a predetermined temperature, the control unit determines that the reformed gas has not reached a predetermined hydrogen concentration, and the switching unit upstream and downstream of the reformed gas flow path. And the upstream side and the reformed gas branch flow path are communicated. As a result, the reformed gas that has not reached the predetermined hydrogen concentration is supplied as fuel from the reformer to the combustion chamber of the reformer via the offgas tank. That is, the reformed gas that has not reached the predetermined hydrogen concentration is used for heating the reformer.

  That is, the reformed gas generated in the reformer that does not reach the predetermined hydrogen concentration is prevented from reaching the hydrogen purifier, and the reformed gas that does not reach the predetermined hydrogen concentration is supplied to the flare. In comparison, the thermal efficiency of the entire apparatus is improved.

On the other hand, when the temperature of the reformed gas in the reformer is equal to or higher than the predetermined temperature, the control unit determines that the reformed gas has reached a predetermined hydrogen concentration, and the switching unit upstream of the reformed gas channel. And the downstream side are in communication with each other, and the upstream side and the reformed gas branch flow path are blocked. Thus, the reformed gas that has reached a predetermined hydrogen concentration is supplied to the hydrogen purifier to produce product hydrogen. Further, off-gas is returned as fuel from the hydrogen purifier to the combustion chamber of the reformer through the off-gas tank, and is used for heating the reformer. Also in this case, the thermal efficiency of the entire hydrogen production apparatus is improved as compared with a hydrogen production apparatus that does not supply off-gas as fuel to the reformer.

  Further, at the time of this switching, the reformed gas stored in the off-gas tank until the reformed gas reaches the hydrogen purifier and the off-gas separated from the reformed gas by the hydrogen purifier reaches the off-gas tank. It can be supplied to the combustion chamber of the reformer. Accordingly, the fuel supply to the combustion chamber of the reformer at the time of switching can be stably maintained and used for heating the reformer.

Thereby, the thermal efficiency of the entire hydrogen production apparatus is further improved as compared with the hydrogen production apparatus that supplies the reformed gas that does not reach the predetermined hydrogen concentration to the flare.
In this way, the control unit determines whether or not the reformed gas has reached a predetermined hydrogen concentration based on the reformed gas temperature of the reformer, and controls the switching means based on this, so that the product The thermal efficiency of the entire apparatus can be improved while maintaining the quality of hydrogen.

Further, in this hydrogen production apparatus, the switching means is switched based on the temperature of the reformed gas, so that the reformed gas that has not reached the predetermined hydrogen concentration is supplied as fuel to the reformer via the offgas tank. The At this time, the flow rate of the reformed gas is detected by the gas flow rate detecting means provided in the off-gas flow path, and the control unit adjusts the flow rate of the air flowing into the combustion chamber of the reformer based on the flow rate and temperature of the reformed gas. By doing so, the combustibility of the combustion chamber is maintained well.

In particular, the control unit refers to not only the flow rate of the reformed gas but also the temperature of the reformed gas, and adjusts the flow rate of air supplied to the combustion chamber in accordance with the composition of the reformed gas depending on the temperature. The chamber is more flammable.
The hydrogen production apparatus according to claim 2 , wherein the reformer is connected to the reformer for reforming hydrocarbons supplied as a raw material to generate a reformed gas mainly composed of hydrogen, and the reformer A hydrogen purifier that separates the gas into product hydrogen and an off-gas that is an impurity to purify the product hydrogen; an off-gas passage that returns the off-gas as fuel to the combustion chamber of the reformer from the hydrogen purifier; and the off-gas An offgas tank that is provided on a flow path and temporarily stores the offgas, and then supplies the reformer to the reformer, and a branch from a reformed gas flow path from the reformer to the hydrogen purifier. The reformed gas branch channel, the upstream side of the reformed gas channel with respect to the branch position to the reformed gas branch channel, and the downstream side or the reformed gas branch channel. Switching means for shutting off from the other, and the reforming A temperature detecting means for detecting the temperature of the reformed gas, a control unit for controlling the switching means based on the temperature of the reformed gas detected by the temperature detecting means, and the off gas tank in the off gas passage. A gas flow rate detecting means for detecting a gas flow rate, an air supply channel for supplying air to the combustion chamber of the reformer, and an air supply channel provided on the air supply channel. An air flow rate adjustment valve for adjusting a flow rate of supplied air, and the control unit adjusts the air flow rate based on the temperature of the reformed gas and the gas flow rate detected by the gas flow rate detection means. The air flow rate is adjusted by controlling the valve.

According to a third aspect of the present invention, there is provided a reformer for reforming a hydrocarbon supplied as a raw material to generate a reformed gas containing hydrogen as a main component, the reformer for steam reforming the hydrocarbon. A reformer having a carbonaceous catalyst layer, and a carbon monoxide removal unit that removes carbon monoxide from the reformed gas downstream of the reforming catalyst layer. A hydrogen purifier that purifies the product hydrogen by separating the gas into product hydrogen and an off-gas that is an impurity; an off-gas passage that returns the off-gas as fuel to the combustion chamber of the reformer from the hydrogen purifier; An off-gas tank provided on an off-gas flow path, temporarily storing the off-gas and then supplying the reformer, and a branch from the reformed gas flow path leading from the reformer to the hydrogen purifier The reformed gas branch flow path leading to the Switching means for communicating with either the upstream side of the branching position to the reformed gas branching channel in the channel, the downstream side, or the reformed gas branching channel, and blocking the other, and the reformer A hydrogen production apparatus comprising: a temperature detection unit that is disposed between the reforming catalyst layer and the carbon monoxide removal unit on the flow path through which the reformed gas flows, and detects the temperature of the reformed gas. When the temperature of the reformed gas generated in the reformer is less than a threshold value, the switching means is upstream of the branch position to the reformed gas branch channel in the reformed gas channel. The switching means in the case where the temperature of the reformed gas generated in the reformer is equal to or higher than a threshold value. Branch position to the reformed gas branch channel in the reformed gas channel. Also communicates an upstream side and a downstream side, causes blocked with said reformed gas branch flow path and the upstream side, if the temperature of at least the reformed gas is less than the threshold value, the temperature of the reformed gas The flow rate of air supplied to the combustion chamber of the reformer is adjusted based on the gas flow rate downstream of the off gas tank in the off gas flow path .
In this hydrogen production method, when the temperature of the reformed gas generated in the reformer is less than the threshold value, it is determined that the reformed gas has not reached the predetermined hydrogen concentration, and the reformed gas flow path is switched by the switching means. The upstream side and the downstream side are blocked, and the upstream side and the reformed gas branch flow path are communicated. As a result, the reformed gas that has not reached the predetermined hydrogen concentration is supplied as fuel from the reformer to the combustion chamber of the reformer via the offgas tank. That is, the reformed gas that has not reached the predetermined hydrogen concentration is used for heating the reformer.

  On the other hand, when the temperature of the reformed gas generated in the reformer is equal to or higher than the threshold value, it is determined that the reformed gas has reached a predetermined hydrogen concentration, and the upstream and downstream sides of the reformed gas channel are switched by the switching means. The upstream side and the reformed gas branch flow path are shut off. Thus, the reformed gas that has reached a predetermined hydrogen concentration is supplied to the hydrogen purifier to produce product hydrogen.

Thus, in this hydrogen production method, it is determined whether the reformed gas has reached a predetermined hydrogen concentration based on the reformed gas temperature of the reformer, and the switching means is controlled based on this. Therefore, the thermal efficiency of the entire apparatus can be improved while maintaining the quality of product hydrogen.
Further, in this hydrogen production method, at least when the temperature of the reformed gas is lower than the threshold, the upstream side and the downstream side of the reformed gas channel are blocked by the switching means, and the upstream side and the reformed gas branch channel To communicate with. Thereby, the reformed gas that has not reached the predetermined hydrogen concentration is supplied as fuel to the reformer via the off-gas tank. At this time, by adjusting the flow rate of air supplied to the combustion chamber of the reformer based on the temperature of the reformed gas and the gas flow rate downstream of the offgas tank in the offgas flow path, the combustibility of the combustion chamber is improved. It can be maintained well.
The hydrogen production method according to claim 4 , wherein the reformer is connected to the reformer for reforming hydrocarbons supplied as a raw material to generate a reformed gas mainly composed of hydrogen, and the reformer A hydrogen purifier that separates the gas into product hydrogen and an off-gas that is an impurity to purify the product hydrogen; an off-gas passage that returns the off-gas as fuel to the combustion chamber of the reformer from the hydrogen purifier; and the off-gas An offgas tank that is provided on a flow path and temporarily stores the offgas, and then supplies the reformer to the reformer, and a branch from a reformed gas flow path from the reformer to the hydrogen purifier. The reformed gas branch channel, the upstream side of the reformed gas channel with respect to the branch position to the reformed gas branch channel, and the downstream side or the reformed gas branch channel. And switching means for blocking from the other When the temperature of the reformed gas generated in the reformer is less than a threshold value using an element manufacturing apparatus, the branching position to the reformed gas branch channel in the reformed gas channel by the switching means If the temperature of the reformed gas generated in the reformer is equal to or higher than a threshold, the upstream side and the downstream side are blocked, the upstream side and the reformed gas branch flow path are communicated, The switching means causes the upstream side and the downstream side of the reformed gas flow path to communicate with the reformed gas branch flow path, and shuts off the upstream side and the reformed gas branch flow path. When at least the temperature of the reformed gas is less than the threshold, the reformer combustion chamber is based on the reformed gas temperature and the gas flow rate downstream of the offgas tank in the offgas passage. The flow rate of air supplied to is adjusted.

Since the hydrogen production apparatus according to the first and second aspects of the present invention has the above-described configuration, a reformed gas that has not reached a predetermined hydrogen concentration when the reformer is started may be supplied to the hydrogen purifier. In addition to being prevented, the thermal efficiency of the entire apparatus can be improved.

The hydrogen production apparatus according to the invention of claim 1, wherein, since the above-described configuration, it is possible to improve the combustion of the reformed gas in the combustion chamber.

Furthermore, since the hydrogen production method according to the third and fourth aspects of the present invention has the above-described configuration, a reformed gas that has not reached a predetermined hydrogen concentration is supplied to the hydrogen purifier when the reformer is started up. In addition, the thermal efficiency of the entire apparatus can be improved.

Moreover, since the hydrogen production method according to the third and fourth aspects of the present invention has the above-described configuration, the combustibility of the reformed gas in the combustion chamber can be improved.

It is the schematic block diagram which showed the hydrogen production apparatus which concerns on 1st Embodiment of this invention. It is sectional drawing which showed the multiple cylinder type | mold reformer which concerns on 1st Embodiment of this invention. It is the block diagram which showed the control structure of the hydrogen production apparatus which concerns on 1st Embodiment of this invention. It is the schematic block diagram which showed the hydrogen production apparatus which concerns on 2nd Embodiment of this invention. It is the block diagram which showed the control structure of the hydrogen production apparatus which concerns on 2nd Embodiment of this invention.

[First Embodiment]
An example of the hydrogen production apparatus and the hydrogen production method according to the first embodiment of the present invention will be described with reference to FIGS.

<Hydrogen production equipment>
As shown in FIG. 1, the hydrogen production apparatus 10 includes a multi-cylinder reformer (hereinafter sometimes referred to as “reformer”) 12 that generates a reformed gas obtained by steam reforming from a hydrocarbon (city gas). And a compressor 80 that compresses the reformed gas, and a hydrogen purifier 90 that purifies hydrogen gas by removing impurities from the compressed reformed gas. In addition, the hydrogen production apparatus 10 includes a pre-pressurization water separation unit 50 and a post-pressurization water separation unit 60 that separate and remove moisture from the reformed gas on the upstream side and the downstream side of the compressor 80, respectively. A combustion exhaust gas water separation unit 70 for separating and removing moisture from the combustion exhaust gas.

  In addition, this hydrogen production apparatus 10 produces hydrogen from a hydrocarbon raw material, and this embodiment demonstrates the case where the city gas which has methane as a main component is used as an example of a hydrocarbon raw material.

(Multiple cylinder reformer)
As shown in FIG. 2, the multiple cylindrical reformer 12 includes a plurality of cylindrical walls 21, 22, 23, and 24 (hereinafter sometimes referred to as “cylindrical walls 21 to 24”) arranged in multiple. Have. The plurality of cylindrical walls 21 to 24 are formed in, for example, a cylindrical shape or an elliptical cylindrical shape. A combustion chamber 25 is formed inside the first cylindrical wall 21 from the inside out of the plurality of cylindrical walls 21 to 24, and a burner 26 is disposed downward on the upper portion of the combustion chamber 25. Yes. This multi-cylinder reformer 12 is an example of a reformer.

  Further, an air supply pipe 40 for supplying combustion air from the outside is connected to the upper end portion of the combustion chamber 25. The burner 26 is further connected to a raw material branch pipe 33A branched from a raw material supply pipe 33 for supplying city gas. An air branch pipe 40A branched from the air supply pipe 40 is connected to the raw material branch pipe 33A. Therefore, the burner 26 is configured to be supplied with a gas obtained by mixing air with city gas. The air supply pipe 40 corresponds to an “air supply flow path”.

  A flue gas flow path 27 is formed between the first cylindrical wall 21 and the second cylindrical 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 discharging gas is connected to the 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 through the combustion exhaust gas channel 27 and is sent to the combustion exhaust gas water separation unit 70 through the gas discharge pipe 28.

  A first flow path 31 is formed between the second cylindrical wall 22 and the third cylindrical wall 23. The upper part of the first flow path 31 is formed as a preheating flow path 32, and a raw material supply pipe 33 for supplying city gas and reforming water are supplied to the upper end portion of the preheating flow path 32. For this purpose, a reforming water supply pipe 34 is connected. Further, a spiral member 35 is provided between the second cylindrical wall 22 and the third cylindrical wall 23, and the preheating channel 32 is formed in a spiral shape by the spiral member 35. Yes.

  The preheating channel 32 can be supplied with city gas from the raw material supply pipe 33, and 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 through the preheating channel 32, and are configured to heat-exchange with the combustion exhaust gas through the second cylindrical wall 22 to vaporize the water. The preheating channel 32 is configured to generate a mixed gas by mixing the city gas and the reforming water (steam) in the gas phase.

  The 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. This is a configuration. The reforming catalyst layer 36 has a configuration in which reformed gas containing hydrogen as a main component is generated by receiving heat from the flue gas flowing through the flue gas passage 27 and causing the gas mixture to undergo a steam reforming reaction.

  In the first flow path 31, a temperature sensor 37 that detects the temperature of the generated reformed gas is disposed on the downstream side of the reforming catalyst layer 36. The detection signal of the temperature sensor 37 is output to the control unit 106 described later. The temperature sensor 37 corresponds to “temperature detection means”.

  Further, a second flow path 42 is formed between the third cylindrical wall 23 and the fourth cylindrical wall 24. The lower end portion of the second flow path 42 is in communication with the lower end portion of the first flow path 31. A lower portion of the second flow path 42 is formed as a reformed gas flow path 43, and a reformed gas discharge pipe 44 is connected to an upper end portion of the second flow path 42.

  Further, a CO shift catalyst layer 45 is provided above the reformed gas channel 43 in the second channel 42, and the reformed gas generated in the reformed catalyst layer 36 is reformed gas channel. After passing through 43, the CO conversion catalyst layer 45 is supplied. In the CO shift catalyst layer 45, carbon monoxide and water vapor contained in the reformed gas react to be converted into hydrogen and carbon dioxide (aqueous shift reaction), and carbon monoxide in the reformed gas can be reduced. .

  Further, an oxidant gas supply pipe 46 is connected to the upper side of the CO shift catalyst layer 45, and a CO selective oxidation catalyst layer 47 is provided above the CO shift catalyst layer 45 in the second flow path 42. ing. The oxidant gas (for example, air) introduced through the oxidant gas supply pipe 46 and the reformed gas that has passed through the CO shift catalyst layer 45 are supplied to the CO selective oxidation catalyst layer 47. In the CO selective oxidation catalyst layer 47, for example, carbon monoxide reacts with oxygen on a noble metal catalyst such as platinum or ruthenium and is converted into carbon dioxide, so that carbon monoxide can be removed. The reformed gas G1 in which carbon monoxide is reduced in the CO shift catalyst layer 45 and the CO selective oxidation catalyst layer 47 is configured to be discharged through the reformed gas discharge pipe 44.

  As shown in FIG. 1, the reformed gas generated in the multi-cylinder reformer 12 is supplied to the pre-pressurization water separator 50, the compressor 80, the post-pressurization water separator 60, and the hydrogen purifier 90 in this order. Flowing. That is, in the gas flow direction, from the upstream side to the downstream side, the multiple cylinder 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. Has been placed.

(Water separation part before pressurization)
The downstream end of the reformed gas discharge pipe 44 through which the reformed gas G1 flows from the multi-cylinder reformer 12 is connected to the pre-pressurization water separator 50. A water recovery pipe 59 is connected to the bottom of the pre-pressurization water separation section 50, and a communication flow path pipe 56 is connected to the top of the pre-pressurization water separation section 50. In the heat exchanger HE1 disposed in the reformed gas discharge pipe 44 upstream of the pre-pressurization water separation unit 50, the reformed gas G1 is condensed and separated by cooling by heat exchange with the cooling water. Water (liquid phase) can be stored in the lower part of the water separation unit 50. The water (liquid phase) is sent to the water recovery pipe 59. The reformed gas G <b> 2 after the water has been condensed is configured to be sent to the communication channel pipe 56.

  In addition, the upstream end of the branch pipe 100 is connected to the connecting flow path pipe 56 on the way. The downstream end of the branch pipe 100 is connected to an offgas tank 112 described later. Further, in the communication channel pipe 56, a first on-off valve 102 that communicates or shuts off the pre-pressurized water separation unit 50 and the compressor 80 is disposed downstream of the branch position with the branch pipe 100. . Further, the branch pipe 100 is provided with a second on-off valve 104 for communicating or blocking the pre-pressurized water separation unit 50 and the off-gas tank 112. The branch pipe 100 corresponds to a “reformed gas branch flow path”. The first on-off valve 102 and the second on-off valve 104 correspond to “switching means”.

  As shown in FIG. 3, the first on-off valve 102 and the second on-off valve 104 are configured to be opened and closed by a control signal from the control unit 106.

  Specifically, when the temperature of the reformed gas detected by the temperature sensor 37 is less than the threshold value, the first on-off valve 102 is closed and the second on-off valve 104 is opened. That is, the pre-pressurization water separation unit 50 and the compressor 80 are shut off, and the pre-pressurization water separation unit 50 and the off-gas tank 112 are communicated.

  On the other hand, when the temperature of the reformed gas detected by the temperature sensor 37 is equal to or higher than the threshold value, the first on-off valve 102 is opened and the second on-off valve 104 is closed. That is, the pre-pressurization water separation unit 50 and the compressor 80 are communicated with each other, and the pre-pressurization water separation unit 50 and the off-gas tank 112 are shut off.

(Compressor)
The compressor 80 includes a communication channel pipe 56 through which the reformed gas G2 from the pre-pressurization water separation unit 50 flows, and a communication channel pipe 66 through which the reformed gas G2 supplied to the post-pressurization water separation unit 60 flows. It is connected. The compressor 80 compresses the reformed gas G <b> 2 supplied from the pre-pressurization water separation unit 50 and can supply it to the post-pressurization water separation unit 60.

(Water separation part after pressurization)
The post-pressurization water separation unit 60 is connected to the downstream end of a communication flow channel 66 through which the reformed gas G <b> 2 flows from the compressor 80. A water recovery pipe 69 is connected to the bottom of the post-pressurization water separation section 60, and a communication channel pipe 68 is connected to the top of the post-pressurization water separation section 60. The reformed gas G2 is condensed and separated by cooling by heat exchange with the cooling water in the heat exchanger HE2 disposed in the communication channel pipe 66 upstream of the post-pressurization water separation unit 60, and the post-pressurization water Water (liquid phase) can be stored in the lower part of the separation unit 60. The water (liquid phase) is sent to the water recovery pipe 69. The reformed gas G <b> 3 after the water is condensed is configured to be sent to the connecting flow path pipe 68.

(Hydrogen purifier)
The hydrogen purifier 90 includes a downstream end of a communication channel pipe 68 through which the reformed gas G3 from the post-pressurization water separation unit 60 flows, an upstream end of a hydrogen supply pipe 92 through which purified hydrogen is sent, and hydrogen purification. The upstream end of the off-gas recirculation pipe 110 to which off-gas separated by the vessel 90 is sent is connected.

  As an example, the hydrogen purifier 90 uses a PSA apparatus. The hydrogen purifier 90 includes a pair of adsorption tanks, performs an adsorption process for adsorbing impurities on the adsorbent in one adsorption tank, and performs a desorption process for desorbing impurities adsorbed on the adsorbent in the other adsorption tank, 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 (off-gas OG), and hydrogen is purified. The purified hydrogen is sent to a hydrogen supply pipe 92 and stored in a tank (not shown) or sent to a hydrogen supply line.

  The off gas of the hydrogen purifier 90 can be supplied to the burner 26 provided in the combustion chamber 25 of the reformer 12 via the off gas recirculation pipe 110. The off gas recirculation pipe 110 corresponds to an “off gas flow path”. Further, the reformed gas flow path from the reformer 12 to the hydrogen purifier 90, specifically, the reformed gas discharge pipe 44, the pre-pressurization water separator 50, the communication flow path pipe 56, the compressor 80, The communication channel pipe 66, the post-pressurization water separation unit 60, and the communication channel pipe 68 correspond to the “reformed gas channel”.

(Combustion exhaust gas water separation part)
A downstream end of a gas exhaust pipe 28 that leads the combustion exhaust gas from the combustion exhaust gas passage 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 separator 70, and a gas discharge pipe 76 is connected to the top of the combustion exhaust gas water separator 70. Combustion exhaust gas discharged from the combustion chamber 25 is condensed and separated by cooling by heat exchange with cooling water in the heat exchanger HE3 disposed in the gas exhaust pipe 28 upstream of the combustion exhaust gas water separation unit 70. The water (liquid phase) can be stored in the lower part of the combustion exhaust gas water separation unit 70. The water (liquid phase) 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 ends of the water recovery pipes 59, 69, 78 are connected to the reforming water supply pipe 34. The reforming water supply pipe 34 is provided with a water treatment device (ion exchange resin) 34A for removing dissolved ion components. An 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 supplied to the multiple cylinder reformer 12 by the pump P1. It is the structure supplied.

<Off gas tank>
The offgas tank 112 is provided on an offgas reflux pipe 110 that communicates the hydrogen purifier 90 and the burner 26 of the reformer 12. Further, the downstream end of the branch pipe 100 is connected to the off gas tank 112.

  Therefore, when the first on-off valve 102 is opened and the second on-off valve 104 is closed, the off-gas supplied from the hydrogen purifier 90 is temporarily stored in the off-gas tank 112, and the flow rate and composition are leveled. Then, it is configured to be supplied to the burner 26 of the reformer 12.

  On the other hand, when the first on-off valve 102 is closed and the second on-off valve 104 is opened, after the reformed gas supplied from the pre-pressurization water separation unit 50 is temporarily stored in the off-gas tank 112, In this configuration, the gas is supplied to the burner 26 of the reformer 12 through the off-gas reflux pipe 110.

(Control part)
Next, the control unit 106 that performs opening / closing control of the first opening / closing valve 102 and the second opening / closing valve 104 will be described.

  As shown in FIG. 3, the control unit 106 receives a detection signal from the temperature sensor 37 and outputs control signals (a valve opening signal and a valve closing signal) to the first on-off valve 102 and the second on-off valve 104. This is a configuration. In particular, the control unit 106 outputs a valve opening signal to one of the first opening / closing valve 102 and the second opening / closing valve 104 and a valve closing signal to the other.

  The controller 106 stores a reformed gas temperature threshold value for determining whether or not a reformed gas (not shown) has reached a predetermined hydrogen concentration. That is, when the temperature of the reformed gas detected by the temperature sensor 37 is input, the control unit 106 is configured to compare the temperature of the reformed gas with a stored threshold value.

  When the temperature of the reformed gas detected by the temperature sensor 37 is equal to or higher than the threshold, the control unit 106 determines that the reformed gas that has reached a predetermined hydrogen concentration has been generated, and performs the first opening / closing. A valve opening signal is output to the valve 102 and a valve closing signal is output to the second on-off valve 104.

  Conversely, when the temperature of the reformed gas detected by the temperature sensor 37 is less than the threshold value, the control unit 106 determines that the reformed gas that has not reached the predetermined hydrogen concentration has been generated, and the first on-off valve A valve closing signal is output to 102 and a valve opening signal is output to the second on-off valve 104.

(Function)
Next, the operation of the hydrogen production apparatus 10 and the hydrogen production method will be described.

  City gas is supplied from the raw material supply pipe 33 to the multiple cylinder reformer 12. As shown in FIG. 2, the city gas supplied to the multi-cylinder reformer 12 is heated while being mixed with reforming water in the preheating flow path 32 of the multi-cylinder reformer 12, and the reforming catalyst Supplied to layer 36. In the reforming catalyst layer 36, heat from the combustion exhaust gas flowing through the combustion exhaust gas passage 27 is received, and a reformed gas containing hydrogen as a main component is generated from the mixed gas by a steam reforming reaction. The reformed gas is supplied to the CO shift catalyst layer 45 through the reformed gas channel 43. In the CO conversion catalyst layer 45, carbon monoxide and water vapor contained in the reformed gas react to be converted into hydrogen and carbon dioxide, and carbon monoxide is reduced.

  Further, the reformed gas that has passed through the CO shift catalyst layer 45 is supplied to the CO selective oxidation catalyst layer 47 together with the oxidizing gas (air) supplied from the oxidant gas supply pipe 46, and carbon monoxide is oxygenated on the noble metal catalyst. It is converted into carbon dioxide by reaction with carbon monoxide. The reformed gas G1 in which carbon monoxide is reduced in the CO selective oxidation catalyst layer 47 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 in which the city gas and air supplied from the raw material branch pipe 33A and the air branch pipe 40A are mixed is 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 channel 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 HE 3, stored in the combustion exhaust gas water separation unit 70, and sent to the water recovery pipe 78. The combustion exhaust gas from which water has been separated is discharged from the gas discharge pipe 76 into the outside air.

  Here, when the hydrogen production apparatus 10 (reformer 12) is started, it takes time until the temperature inside the reformer reaches a predetermined temperature by burning the burner 26 in the combustion chamber 25 of the reformer 12. . During this time, the reformed gas generated by the steam reforming in the reforming catalyst layer 36 does not reach a predetermined hydrogen concentration by heat exchange with the combustion exhaust gas flowing through the combustion exhaust gas passage 27. Further, the temperature of the reformed gas that has not reached the predetermined hydrogen concentration is lower than the temperature of the reformed gas that has reached the predetermined hydrogen concentration.

  The temperature of the generated reformed gas is detected by a temperature sensor 37 provided on the downstream side of the reforming catalyst layer 36 of the first flow path 31. The control unit 106 determines whether the temperature of the reformed gas detected by the temperature sensor 37 is equal to or higher than a threshold value.

  When the temperature of the reformed gas is lower than the threshold value, it is determined that the reformed gas does not reach the predetermined hydrogen concentration, a valve closing signal is output to the first on-off valve 102, and the second on-off valve 104 is opened. The valve signal is output.

  As a result, the first on-off valve 102 is closed and the second on-off valve 104 is opened. As a result, the pre-pressurization water separation unit 50 and the compressor 80 are disconnected, and the pre-pressurization water separation unit 50 and the off-gas tank 112 are communicated.

  In this state, the reformed gas G 1 that has not reached the predetermined hydrogen concentration sent from the reformer 12 to the reformed gas discharge pipe 44 is supplied to the pre-pressurization water separation unit 50. In the pre-pressurization water separation unit 50, water condensed by cooling due to heat exchange in the heat exchanger HE <b> 1 is stored and sent to the water recovery pipe 59.

  The reformed gas G2 from which the water has been separated is supplied from the communication channel pipe 56 to the off-gas tank 112 via the branch pipe 100. The reformed gas G2 once stored in the offgas tank 112 is supplied to the burner 26 of the reformer 12 through the offgas recirculation pipe 110 and burned in the combustion chamber 25 (used for heating the reformer 12). ).

  On the other hand, when the temperature of the reformed gas detected by the temperature sensor 37 is equal to or higher than the threshold value, the control unit 106 determines that the reformed gas generated by the reformer 12 has reached a predetermined hydrogen concentration. The valve opening signal is output to the first opening / closing valve 102 and the valve closing signal is output to the second opening / closing valve 104.

  As a result, the first on-off valve 102 is opened and the second on-off valve 104 is closed. As a result, the pre-pressurization water separation unit 50 and the compressor 80 are communicated, and the pre-pressurization water separation unit 50 and the off-gas tank 112 are shut off.

  Therefore, as shown in FIG. 1, the reformed gas G1 of a predetermined quality sent from the reformer 12 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 due to heat exchange in the heat exchanger HE <b> 1 is stored and sent to the water recovery pipe 59. The reformed gas G <b> 2 from which 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 from the communication channel pipe 66 to the post-pressurization water separation unit 60. In the post-pressurization water separation unit 60, water condensed by cooling due to heat exchange in the heat exchanger HE <b> 2 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 connecting 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, respectively, is returned to the reforming water supply pipe 34. By driving the pump P1, the reforming water supply pipe 34 supplies the multi-tubular reformer 12 as reforming water.

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

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

  On the other hand, the off-gas OG discharged from the hydrogen purifier 90 is supplied to the reformer 12 through the off-gas recirculation pipe 110. That is, the gas is once stored in an offgas tank 112 provided on the offgas recirculation pipe 110 and then supplied to the burner 26 of the reformer 12.

  This off-gas OG contains carbon monoxide that could not be removed by the reformer 12 and hydrogen that could not be separated by the hydrogen purifier 90. Accordingly, the off gas is burned in the combustion chamber 25 by being supplied to the burner 26 (used for heating the reformer 12).

  By the way, when the first on-off valve 102 is switched from closed to open and the second on-off valve 104 is switched from open to closed (hereinafter referred to as “switching”), the reformed gas is supplied to the pre-pressurization water separation unit. It takes time until the off-gas OG that has been separated from the reformed gas G3 by the hydrogen purifier 90 reaches the off-gas tank 112 via the off-gas recirculation pipe 110.

  During this time, there is no combustible gas (reformed gas G2 and offgas OG) supplied to the offgas tank 112, but the reformed gas G2 stored in the offgas tank 112 is supplied from the offgas tank 112 to the burner 26 of the reformer 12. Is done. That is, the supply of fuel gas (reformed gas G2 or offgas OG) from the offgas tank 112 to the burner 26 is continued without being cut off. Therefore, the combustion state of the burner 26 is maintained well.

  As described above, in the hydrogen production apparatus 10, when the reformed gas generated in the reformer 12 does not reach a predetermined hydrogen concentration, the first on-off valve 102 is closed and the second on-off valve 104 is opened. By turning the valve, it can be supplied to the off-gas tank 112 provided on the off-gas recirculation pipe 110 via the branch pipe 100. As a result, the reformed gas that has not reached the predetermined hydrogen concentration is supplied as fuel from the off-gas tank 112 to the burner 26 of the reformer 12 and burned in the combustion chamber 25.

  Therefore, the reformed gas that has not reached the predetermined hydrogen concentration is prevented from being supplied to the hydrogen purifier 90, and the purity (quality) of the (product) hydrogen purified by the hydrogen purifier 90 is prevented from decreasing. (Product hydrogen quality can be kept high).

  Further, compared with a hydrogen production apparatus that supplies reformed gas that has not reached a predetermined hydrogen concentration to the burner 26 of the reformer 12 and burns it in the combustion chamber 25 to supply this reformed gas to the flare. The thermal efficiency of the hydrogen production apparatus 10 is improved.

  Further, since the control unit 106 determines whether or not the reformed gas has reached a predetermined quality based on the temperature of the reformed gas detected by the temperature sensor 37, the quality of the reformed gas is accurately determined. Can be determined.

  Furthermore, when switching from the state in which the reformed gas is supplied to the offgas tank 112 to the state in which the offgas is supplied to the offgas tank 112 (at the time of switching), the supply of the reformed gas to the offgas tank 112 is stopped. Until the off gas reaches the off gas tank 112 from the state, the reformed gas stored in the off gas tank 112 is supplied to the burner 26 of the reformer 12. Therefore, the supply of the fuel gas (reformed gas or off gas) from the off gas tank 112 to the burner 26 is not shut off, and the combustibility of the burner 26 is maintained well.

  When the supply of fuel gas (reformed gas or off gas) from the off gas tank 112 to the burner 26 is interrupted, it is necessary to supply city gas to the burner 26 or increase the supply amount of city gas. . In the hydrogen production apparatus 10, since the supply of fuel gas (reformed gas or off gas) from the off gas tank 112 to the burner 26 is not interrupted at the time of switching, the fuel gas (reformed gas, off gas, city gas) to the burner 26 is not interrupted. The flow rate control is simplified and the thermal efficiency of the entire apparatus is further improved.

  Note that an offgas tank 112 is provided in the middle of the offgas recirculation pipe 110, and the offgas OG is temporarily stored in the offgas tank 112. For example, when the hydrogen purifier 90 is a PSA device, the flow rate and composition of the offgas periodically fluctuate. Can be supplied to the burner 26 of the reformer 12. Thereby, the combustibility of the burner 26 can be maintained satisfactorily.

[Second Embodiment]
A hydrogen production apparatus 200 and a hydrogen production method according to a second embodiment of the present invention will be described with reference to FIGS. 4 and 5. The same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted. In addition, since the hydrogen production apparatus 200 has only the flow rate detector 202 and the flow rate control valve 204 added to the hydrogen production apparatus 10, only the configuration and operation relating to the part will be described, and the same operational effects as in the first embodiment will be described. Will not be described in detail.

(Constitution)
As shown in FIG. 4, the hydrogen production apparatus 200 is provided with a flow rate detector 202 that detects the flow rate of the gas flowing through the offgas recirculation pipe 110 on the offgas recirculation pipe 110 on the downstream side of the offgas tank 112. As shown in FIG. 5, the detection signal of the flow rate detector 202 is output to the control unit 106. The flow rate detector 202 corresponds to “flow rate detection means”.

  As shown in FIG. 4, a flow control valve 204 that adjusts the flow rate of air flowing through the air supply pipe 40 is provided on the air supply pipe 40. As shown in FIG. 5, the flow control valve 204 is driven by a control signal from the control unit 106 and adjusts the flow rate of air flowing through the air supply pipe 40. This flow control valve 204 corresponds to an “air flow adjustment valve”.

  As shown in FIG. 5, the control unit 106 receives detection signals from the temperature sensor 37 and the flow rate detector 202 and outputs control signals to the first on-off valve 102, the second on-off valve 104, and the flow rate control valve 204. It is the composition which is done.

  Further, the control unit 106 includes a flow rate and temperature of the reformed gas detected by the flow rate detector 202 and the temperature sensor 37, and an air flow rate flowing through the air supply pipe 40 corresponding thereto (opening degree of the air flow rate adjustment valve). Is stored. This is because when the reformed gas is supplied to the burner 26 and combusted, the composition of the reformed gas varies depending on the temperature of the reformed gas, so that the combustion chamber 25 corresponds to the flow rate and temperature of the reformed gas. The combustibility (air-fuel ratio) in the combustion chamber 25 is appropriately adjusted by adjusting the air flow rate supplied to the combustion chamber 25.

  Therefore, the control unit 106 compares the temperature detected by the temperature sensor 37 with a threshold value to output a control signal to the first on-off valve 102 and the second on-off valve 104 to perform on-off control. When the reformed gas is supplied to the off-gas tank 112, a control signal referring to a table (not shown) is output to the flow control valve 204.

(Function)
Next, the operation of the hydrogen production apparatus 200 and the hydrogen production method will be described.
In the control unit 106 of the hydrogen production apparatus 200, when the temperature of the reformed gas detected by the temperature sensor 37 is less than the threshold when the reformer 12 is started, the reformed gas has reached a predetermined hydrogen concentration. It is determined that the first on-off valve 102 is closed, and the second on-off valve 104 is output as a valve opening signal. As a result, the first on-off valve 102 is closed and the second on-off valve 104 is opened.

  As a result, the reformed gas that is generated in the reformer 12 and does not reach a predetermined hydrogen concentration when the apparatus is started is supplied from the pre-pressurization water separation unit 50 to the off-gas tank 112. Reformed gas is supplied from the off gas tank 112 to the burner 26 of the reformer 12 through the off gas recirculation pipe 110. At this time, the flow rate of the reformed gas flowing in the off gas recirculation pipe 110 is detected by the flow rate detector 202.

  In the control unit 106, when the reformed gas temperature is lower than the threshold value as described above, the reformed gas is supplied to the burner 26 of the combustion chamber 25. Therefore, the temperature sensor 37 and the flow rate are referred to by referring to a table (not shown). The opening degree of the flow control valve 204 is determined from the temperature and flow rate of the reformed gas detected by the detector 202, and a control signal corresponding to this is output to the flow control valve 204.

  The flow rate control valve 204 adjusts to a predetermined opening based on the control signal, so that the air flow rate supplied from the air supply pipe 40 to the combustion chamber 25 becomes a predetermined flow rate. As a result, the combustion state of the reformed gas supplied to the burner 26 in the combustion chamber 25 is better maintained.

  In this case, the composition of the reformed gas is taken into account by referring to not only the flow rate of the reformed gas but also the temperature of the reformed gas, so that the burnability of the burner 26 in the combustion chamber 25 is further improved.

[Others]
In the hydrogen production apparatuses 10 and 200, the reformer 12 is a multi-cylinder reformer, but the present invention is not limited to this. Any gas can be used as long as it can be reformed from city gas into a reformed gas mainly composed of hydrogen.

  Further, in the hydrogen production apparatuses 10 and 200, the case where the hydrogen purifier 90 is a PSA apparatus has been described, but the present invention is not limited to this as long as hydrogen can be purified from the reformed gas G3.

  Furthermore, in the hydrogen production apparatuses 10 and 200, by providing the first on-off valve 102 on the downstream side of the branch position with the branch pipe 100 on the communication flow path pipe 56 and the second on-off valve 104 on the branch pipe 100, Although the pre-pressurization water separation unit 50 and the compressor 80 or the off-gas tank 112 are selectively communicated with each other, the pre-pressurization water separation is provided by providing a three-way valve at a branch position with the branch pipe 100 on the communication flow path pipe 56. The unit 50 and the compressor 80 or the off-gas tank 112 may be selectively communicated with each other.

  In the hydrogen production apparatuses 10 and 200, the control unit 106 determines the hydrogen concentration of the reformed gas based on the temperature of the reformed gas detected by the temperature sensor 37, and the first on-off valve 102, Although the opening / closing control of the second opening / closing valve 104 is performed, the operator evaluates the hydrogen concentration of the reformed gas based on the temperature of the reformed gas, and opens / closes the first opening / closing valve 102 and the second opening / closing valve 104. The structure to perform may be sufficient.

  Furthermore, the control unit 106 may determine whether or not the reformed gas has reached a predetermined hydrogen concentration based on the temperature of the reformed gas. For example, it may be determined whether the reformed gas has reached a predetermined hydrogen concentration based on the temperature rise rate of the reformed gas or the like.

  In the hydrogen production apparatus 200, the control unit 106 adjusts the flow rate of air supplied to the combustion chamber 25 of the reformer 12 from the temperature and flow rate of the reformed gas by the flow rate control valve 204. The structure which adjusts the air flow volume supplied to the combustion chamber 25 corresponding to only a flow volume may be sufficient.

  Further, in the hydrogen production apparatus 200, only when the reformed gas is supplied to the burner 26 of the reformer 12, the flow rate control valve 204 is adjusted to adjust the flow rate of air supplied to the combustion chamber 25. The same adjustment may be made when off-gas is supplied to the burner 26. However, in this case, the control unit 106 stores a table indicating the correspondence relationship between the off-gas flow rate and the air flow rate (the opening degree of the flow control valve 204), and the table is obtained from the off-gas flow rate detected by the flow rate detector 202. It is considered that the air flow rate is adjusted by controlling the flow rate control valve 204 with reference to FIG.

  Moreover, in the hydrogen production apparatuses 10 and 200, one end of the branch pipe 100 is connected to the pre-pressurization water separation unit 50, but is not limited thereto. That is, one end of the branch pipe 100 is connected to a pipe line (the reformed gas discharge pipe 44, the pre-pressurization water separation unit 50, the communication channel pipe 56, the compressor 80, the communication channel) connecting the reformer 12 and the hydrogen purifier 90. It only has to be connected to the pipe 66, the post-pressurization water separation section 60, and the connecting flow path pipe 68). However, when one end of the branch pipe 100 is connected to the downstream side of the pre-pressurization water separation unit 50, the flow path until the reformed gas is supplied to the off-gas tank 112 becomes longer than in the present embodiment. It is disadvantageous. In addition, when the branch pipe 100 is connected from the reformed gas discharge pipe 44 to the off-gas tank 112, the reformed gas containing a large amount of water vapor (water) is supplied to the burner 26 of the reformer 12. Disadvantageous over form.

  Furthermore, although the other end of the branch pipe 100 is directly connected to the off-gas tank 112, the present invention is not limited to this. That is, the other end of the branch pipe 100 may be connected to the upstream side of the offgas tank 112 in the offgas recirculation pipe 110.

  Further, in the hydrogen production apparatuses 10 and 200, the start-up of the reformer 12 (hydrogen production apparatuses 10 and 200) has been described. However, the reformer is not limited to the start-up and does not reach a predetermined hydrogen concentration. 12 burners 26 are supplied.

10, 200 Hydrogen production equipment 12 Multiple cylinder reformer (reformer)
37 Temperature sensor (temperature detection means)
40 Air supply pipe (air supply flow path)
44 Reformed gas discharge pipe (reformed gas flow path)
50 Water separator before pressurization (reformed gas flow path)
56 Communication channel (reformed gas channel)
80 Compressor (reformed gas flow path)
66 Communication channel (reformed gas channel)
60 Water separator after pressurization (reformed gas flow path)
68 Connecting channel pipe (reformed gas channel)
100 branch pipe (reformed gas branch flow path)
102 1st on-off valve (switching means)
104 Second on-off valve (switching means)
106 Control part 110 Off-gas recirculation pipe (off-gas flow path)
112 Off-gas tank 202 Flow rate detector (flow rate detection means)
204 Flow control valve (air flow control valve)

Claims (4)

A reformer for reforming a hydrocarbon supplied as a raw material to generate a reformed gas mainly composed of hydrogen, comprising a reforming catalyst layer for steam reforming the hydrocarbon, and a reforming catalyst layer A reformer having a carbon monoxide removal section for removing carbon monoxide from the reformed gas on the downstream side,
A hydrogen purifier that is connected to the reformer and separates the reformed gas into product hydrogen and an off-gas that is an impurity to purify product hydrogen;
An offgas passage for returning the offgas as fuel from the hydrogen purifier to the combustion chamber of the reformer;
An off-gas tank provided on the off-gas flow path, temporarily storing the off-gas, and then supplying the reformer;
A reformed gas branch channel that branches from the reformed gas channel leading from the reformer to the hydrogen purifier and reaches the off-gas tank;
Switching means for communicating with either the upstream side of the branch position to the reformed gas branch channel in the reformed gas channel, the downstream side or the reformed gas branch channel, and blocking the other;
A temperature detecting unit disposed between the reforming catalyst layer and the carbon monoxide removing unit on the flow path through which the reformed gas of the reformer flows, and detecting the temperature of the reformed gas;
A control unit for controlling the switching means based on the temperature of the reformed gas detected by the temperature detecting means;
A gas flow rate detecting means provided downstream of the offgas tank in the offgas flow path for detecting a gas flow rate;
An air supply flow path for supplying air to the combustion chamber of the reformer;
An air flow rate adjusting valve that is provided on the air supply flow path and adjusts the flow rate of air supplied to the combustion chamber;
And the control unit adjusts the air flow rate by controlling the air flow rate adjustment valve based on the temperature of the reformed gas and the gas flow rate detected by the gas flow rate detection means . A reformer for reforming hydrocarbons supplied as a raw material to generate a reformed gas mainly composed of hydrogen;
A hydrogen purifier that is connected to the reformer and separates the reformed gas into product hydrogen and an off-gas that is an impurity to purify product hydrogen;
An offgas passage for returning the offgas as fuel from the hydrogen purifier to the combustion chamber of the reformer;
An off-gas tank provided on the off-gas flow path, temporarily storing the off-gas, and then supplying the reformer;
A reformed gas branch channel that branches from the reformed gas channel leading from the reformer to the hydrogen purifier and reaches the off-gas tank;
Switching means for communicating with either the upstream side of the branch position to the reformed gas branch channel in the reformed gas channel, the downstream side or the reformed gas branch channel, and blocking the other;
Temperature detecting means for detecting the temperature of the reformed gas in the reformer;
A control unit for controlling the switching means based on the temperature of the reformed gas detected by the temperature detecting means;
A gas flow rate detecting means provided downstream of the offgas tank in the offgas flow path for detecting a gas flow rate;
An air supply flow path for supplying air to the combustion chamber of the reformer;
An air flow rate adjusting valve that is provided on the air supply flow path and adjusts the flow rate of air supplied to the combustion chamber;
And the control unit adjusts the air flow rate by controlling the air flow rate adjustment valve based on the temperature of the reformed gas and the gas flow rate detected by the gas flow rate detection means. A reformer for reforming a hydrocarbon supplied as a raw material to generate a reformed gas mainly composed of hydrogen, a reforming catalyst layer for steam reforming the hydrocarbon, and the reforming catalyst layer A reformer having a carbon monoxide removal unit for removing carbon monoxide from the reformed gas at a downstream side,
A hydrogen purifier that is connected to the reformer and separates the reformed gas into product hydrogen and an off-gas that is an impurity to purify product hydrogen;
An offgas passage for returning the offgas as fuel from the hydrogen purifier to the combustion chamber of the reformer;
An off-gas tank provided on the off-gas flow path, temporarily storing the off-gas, and then supplying the reformer;
A reformed gas branch channel that branches from the reformed gas channel leading from the reformer to the hydrogen purifier and reaches the off-gas tank;
Switching means for communicating with either the upstream side of the branch position to the reformed gas branch channel in the reformed gas channel, the downstream side or the reformed gas branch channel, and blocking the other;
A temperature detecting unit disposed between the reforming catalyst layer and the carbon monoxide removing unit on the flow path through which the reformed gas of the reformer flows, and detecting the temperature of the reformed gas;
Using a hydrogen production apparatus comprising:
When the temperature of the reformed gas generated by the reformer is less than a threshold value, the switching means causes the upstream side and the downstream side of the branch position to the reformed gas branch channel in the reformed gas channel. And communicating the upstream side and the reformed gas branch flow path,
When the temperature of the reformed gas generated in the reformer is equal to or higher than a threshold value, the switching means causes the reformed gas channel to be upstream and downstream of the branch position to the reformed gas branch channel. And the upstream side and the reformed gas branch flow path are shut off ,
If at least the temperature of the reformed gas is lower than the threshold value, the reformer gas enters the combustion chamber of the reformer based on the temperature of the reformed gas and the gas flow rate downstream of the offgas tank in the offgas passage. A hydrogen production method for adjusting the flow rate of supplied air . A reformer for reforming hydrocarbons supplied as a raw material to generate a reformed gas mainly composed of hydrogen;
A hydrogen purifier that is connected to the reformer and separates the reformed gas into product hydrogen and an off-gas that is an impurity to purify product hydrogen;
An offgas passage for returning the offgas as fuel from the hydrogen purifier to the combustion chamber of the reformer;
An off-gas tank provided on the off-gas flow path, temporarily storing the off-gas, and then supplying the reformer;
A reformed gas branch channel that branches from the reformed gas channel leading from the reformer to the hydrogen purifier and reaches the off-gas tank;
Switching means for communicating with either the upstream side of the branch position to the reformed gas branch channel in the reformed gas channel, the downstream side or the reformed gas branch channel, and blocking the other;
Using a hydrogen production apparatus comprising:
When the temperature of the reformed gas generated by the reformer is less than a threshold value, the switching means causes the upstream side and the downstream side of the branch position to the reformed gas branch channel in the reformed gas channel. And communicating the upstream side and the reformed gas branch flow path,
When the temperature of the reformed gas generated in the reformer is equal to or higher than a threshold value, the switching means causes the reformed gas channel to be upstream and downstream of the branch position to the reformed gas branch channel. And the upstream side and the reformed gas branch flow path are shut off,
If at least the temperature of the reformed gas is lower than the threshold value, the reformer gas enters the combustion chamber of the reformer based on the temperature of the reformed gas and the gas flow rate downstream of the offgas tank in the offgas passage. A hydrogen production method for adjusting the flow rate of supplied air.