JP7068888B2 - Hydrogen production equipment - Google Patents

Description

In the present invention, the raw material gas is a water vapor mixing unit that mixes water vapor so that the ratio of the number of moles of water vapor mixed with the raw material gas, which is a hydrocarbon gas, to the number of moles of carbon in the raw material gas is a target ratio. From the reforming unit equipped with a reforming reaction unit that reforms into a reforming gas containing a large amount of hydrogen by steam reforming treatment and a combustion unit that heats the reforming reaction unit to the temperature for reforming reaction, and the reforming unit. A pressure fluctuation adsorption unit equipped with an adsorption tower that adsorbs a component to be adsorbed other than the hydrogen component from the reformed gas to an adsorbent to generate a product gas, and an off that collects the off gas discharged from the pressure fluctuation adsorption unit. The present invention relates to a hydrogen production apparatus provided with a gas tank, an off-gas supply path for supplying the off-gas stored in the off-gas tank to the combustion unit, and a control unit for controlling the operation of the reforming unit and the pressure fluctuation adsorption unit. ..

In such a hydrogen production apparatus, the raw material gas, which is a hydrocarbon-based gas such as natural gas or naphtha, is reformed into a reformed gas containing a large amount of hydrogen by steam reforming treatment by the reforming section, and hydrogen is reformed by the pressure fluctuation adsorption section. A product gas having a high hydrogen concentration is produced by adsorbing an adsorption target component to an adsorbent from a reformed gas containing an adsorption target component other than the component and the hydrogen component.

Since the off-gas discharged from the pressure fluctuation adsorption part contains combustible components, the off-gas discharged from the pressure fluctuation adsorption part is collected in the off-gas tank, and the off-gas stored in the off-gas tank is collected in the reforming part. The reforming reaction section is supplied to a burning section to be heated and burned (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2004-299995

In the hydrogen production apparatus, the amount of off-gas stored in the off-gas tank may become excessive, resulting in waste of releasing the off-gas stored in the off-gas tank to the outside, and improvement has been desired.

That is, for example, when the production amount of the product gas is reduced, the amount of off-gas collected and stored in the off-gas tank becomes excessive, and the off-gas stored in the off-gas tank may be released to the outside.
To add an explanation, the production amount of product gas will fluctuate according to the change in the consumption amount of the consumption part that consumes the product gas, and when the production amount of the product gas is reduced, it is supplied to the reforming part. It will reduce the supply of raw material gas.
Then, when the supply amount of the raw material gas supplied to the reforming section is reduced, the off gas consumed in the combustion section to heat the reforming reaction section of the reforming section to the reforming reaction temperature according to the reduction. The amount of will decrease.

However, immediately after the supply amount of the raw material gas supplied to the reforming section is reduced, a large amount of reforming gas before the supply amount of the raw material gas is reduced is supplied to the pressure fluctuation adsorption section. Therefore, a large amount of off-gas is discharged from the pressure fluctuation adsorption part, and as a result, the amount of off-gas collected and stored in the off-gas tank may become excessive. In such a case, the off-gas tank may be used. The stored off-gas was released to the outside.

The present invention has been made in view of the above circumstances, and an object of the present invention is to satisfactorily perform reforming treatment of a reforming portion while avoiding releasing off-gas stored in an off-gas tank to the outside. The point is to provide a hydrogen production device capable of producing hydrogen.

The hydrogen production apparatus of the present invention is a steam mixing unit that mixes steam so that the ratio of the number of moles of steam mixed with the raw material gas, which is a hydrocarbon gas, to the number of moles of carbon in the raw material gas is set as a target ratio. A reforming reaction unit that reforms the raw material gas into a reforming gas containing a large amount of hydrogen by steam reforming treatment, a reforming unit provided with a combustion unit that heats the reforming reaction unit to a reforming reaction temperature, and the reforming unit. A pressure fluctuation adsorption unit equipped with an adsorption tower that adsorbs a component to be adsorbed other than the hydrogen component from the reforming gas to an adsorbent to generate a product gas, and an off gas discharged from the pressure fluctuation adsorption unit. An off-gas tank for collecting hydrogen, an off-gas supply path for supplying the off-gas stored in the off-gas tank to the combustion unit, and a control unit for controlling the operation of the reforming unit and the pressure fluctuation adsorption unit. And its characteristic composition is
An off-gas amount detection unit for detecting the off-gas storage amount of the off-gas stored in the off-gas tank is provided.
When the control unit repeatedly increases or decreases with the operation of the pressure fluctuation adsorption unit and the maximum value of the off-gas storage amount is equal to or less than the set appropriate upper limit value, the reforming unit is operated in the reference operating state and When the maximum value is larger than the set appropriate upper limit value, the operating state of the reforming unit is consumed in the combustion unit while the processing amount of the raw material gas is maintained at the same processing amount. It is configured to change the off-gas consumption to an off-gas consumption increasing operating state that increases the amount consumed in the reference operating state.
The control unit changes the reforming reaction temperature to an off-gas consumption increase target temperature higher than the reference target temperature in the reference operation state in the off-gas consumption increase operation state .

That is, the off-gas storage amount of the off-gas stored in the off-gas tank repeatedly increases or decreases with the operation of the pressure fluctuation adsorption unit, and the maximum value of the off-gas storage amount stored in the off-gas tank is set appropriately. In the case of the upper limit or less, the control unit operates the reforming unit in the reference operation state.
Then, when the maximum value of the off-gas storage amount stored in the off-gas tank becomes larger than the set appropriate upper limit value, the control unit keeps the operating state of the reforming unit at the same processing amount of the raw material gas. In this state, the amount of off-gas consumed in the combustion unit is changed to the off-gas consumption increasing operating state in which the amount consumed in the standard operating state is increased.

In this way, when the maximum value of the off-gas storage amount stored in the off-gas tank becomes larger than the set appropriate upper limit value, the consumption of off-gas consumed in the combustion part of the reforming part increases, so that the off-gas tank is used. Since the consumption of the stored off-gas also increases, it is possible to avoid releasing the off-gas stored in the off-gas tank to the outside.

Then, in the off-gas consumption increasing operating state, for example, the reforming reaction section is heated to a high temperature at which the reforming reaction can easily proceed compared to the standard operating state, and the raw material gas is satisfactorily converted into the reformed gas by the steam reforming treatment. It is possible to satisfactorily reform the reformed portion, such as reforming.

In short, according to the characteristic configuration of the hydrogen production apparatus of the present invention, it is possible to satisfactorily perform the reforming treatment of the reforming portion while avoiding releasing the off-gas stored in the off-gas tank to the outside.

Further , in the off-gas consumption increase operating state, the reforming reaction temperature of the reforming reaction unit is set to a high temperature at which the reforming reaction can be easily proceeded by setting the off-gas consumption increasing target temperature higher than the reference target temperature in the standard operating state. By heating the reforming reaction section, the raw material gas can be satisfactorily reformed into a reformed gas by the steam reforming treatment.

That is, if the reforming reaction temperature of the reforming reaction section is set to a high temperature, the reforming reaction of the reforming reaction section can be easily proceeded, but the reforming reaction section is heated to a high temperature by using a gas other than off-gas. In order to avoid heating to the above, the reforming reaction temperature is set to a reference target temperature that can be heated by consuming off-gas in the reference operation state.

Then, when the maximum value of the off-gas storage amount of the off-gas stored in the off-gas tank becomes larger than the set appropriate upper limit value, the excess off-gas is consumed by the reforming reaction unit at a temperature higher than the reference target temperature. By using it for heating to the target temperature for increasing the amount, it is possible to satisfactorily perform the steam reforming treatment in the reformed portion.

In short, according to the characteristic configuration of the hydrogen production apparatus of the present invention, the excess off-gas is used to heat the reforming reaction section to the target temperature for increasing the off-gas consumption, so that the steam in the reforming section is steamed. The reforming process can be performed satisfactorily.

The hydrogen production apparatus of the present invention is a steam mixing unit that mixes steam so that the ratio of the number of moles of steam mixed with the raw material gas, which is a hydrocarbon-based gas, to the number of moles of carbon in the raw material gas is set as a target ratio. A reforming reaction unit that reforms the raw material gas into a reforming gas containing a large amount of hydrogen by steam reforming treatment, a reforming unit provided with a combustion unit that heats the reforming reaction unit to a reforming reaction temperature, and the reforming unit. A pressure fluctuation adsorption unit equipped with an adsorption tower that adsorbs components other than the hydrogen component to be adsorbed from the reformed gas to the adsorbent to generate product gas, and an off gas discharged from the pressure fluctuation adsorption unit. An off-gas tank for recovering hydrogen, an off-gas supply path for supplying the off-gas stored in the off-gas tank to the combustion unit, and a control unit for controlling the operation of the reforming unit and the pressure fluctuation adsorption unit are provided. It is a thing, and its characteristic composition is
An off-gas amount detection unit for detecting the off-gas storage amount of the off-gas stored in the off-gas tank is provided.
When the control unit repeatedly increases or decreases with the operation of the pressure fluctuation adsorption unit and the maximum value of the off-gas storage amount is equal to or less than the set appropriate upper limit value, the reforming unit is operated in the reference operating state and When the maximum value is larger than the set appropriate upper limit value, the operating state of the reforming unit is consumed in the combustion unit while the processing amount of the raw material gas is maintained at the same processing amount. It is configured to change the off-gas consumption to an off-gas consumption increasing operating state that increases the amount consumed in the reference operating state.
The control unit changes the target ratio to an off-gas consumption increase ratio that is larger than the reference operation ratio in the reference operation state in the off-gas consumption increase operation state.

That is, the off-gas storage amount of the off-gas stored in the off-gas tank repeatedly increases or decreases with the operation of the pressure fluctuation adsorption unit, and the maximum value of the off-gas storage amount stored in the off-gas tank is set appropriately. In the case of the upper limit or less, the control unit operates the reforming unit in the reference operation state.
Then, when the maximum value of the off-gas storage amount stored in the off-gas tank becomes larger than the set appropriate upper limit value, the control unit keeps the operating state of the reforming unit at the same processing amount of the raw material gas. In this state, the amount of off-gas consumed in the combustion unit is changed to the off-gas consumption increasing operating state in which the amount consumed in the standard operating state is increased.
In this way, when the maximum value of the off-gas storage amount stored in the off-gas tank becomes larger than the set appropriate upper limit value, the consumption of off-gas consumed in the combustion part of the reforming part increases, so that the off-gas tank is used. Since the consumption of the stored off-gas also increases, it is possible to avoid releasing the off-gas stored in the off-gas tank to the outside.
Then, in the off-gas consumption increasing operating state, for example, the reforming reaction section is heated to a high temperature at which the reforming reaction can easily proceed compared to the standard operating state, and the raw material gas is satisfactorily converted into the reformed gas by the steam reforming treatment. It is possible to satisfactorily reform the reformed portion, such as reforming.
In short, according to the characteristic configuration of the hydrogen production apparatus of the present invention, it is possible to satisfactorily perform the reforming treatment of the reforming portion while avoiding releasing the off-gas stored in the off-gas tank to the outside.
Further , in the off-gas consumption increased operating state, the target ratio, which is the ratio of the number of moles of water vapor supplied to the raw material gas to the number of moles of carbon in the raw material gas, is larger than the standard operating ratio in the standard operating state. As a result of changing to the amount increase ratio, the amount of off-gas consumed in the combustion part increases because the reforming reaction part is heated to the reforming reaction temperature.

That is, the target ratio (S / C), which is the ratio of the number of moles of steam supplied to the raw material gas to the number of moles of carbon in the raw material gas, is based on the theoretical value for steam reforming the raw material gas into the reformed gas. If it is set to a large value, it becomes easy to proceed with the reforming reaction of the reforming reaction section.
However, as the target ratio (S / C) is set to a larger value, the amount of off-gas consumed in the combustion section increases because the reforming reaction section is heated to the reforming reaction temperature. In order to avoid heating the reforming reaction section with a gas other than off-gas, the target ratio (S / C) in the standard operating state is set to a standard operating ratio that is slightly larger than the theoretical value. Has been done.

When the maximum value of the off-gas storage amount of the off-gas stored in the off-gas tank becomes larger than the set appropriate upper limit value, the reforming reaction section is heated to the reforming reaction temperature, which is a surplus. In view of the fact that a large amount of off-gas can be used, by setting the target ratio (S / C) to the off-gas consumption increase ratio, steam reforming in the reforming section can be performed while consuming the excess off-gas. It can be done well.

In short, according to the characteristic configuration of the hydrogen production apparatus of the present invention, the steam reforming treatment in the reforming section is performed while the target ratio is set to the off gas consumption increasing ratio so that the surplus off gas is consumed. It can be done well.

A further characteristic configuration of the hydrogen production apparatus of the present invention is that when the maximum value of the off-gas storage amount that the control unit repeatedly increases or decreases with the operation of the pressure fluctuation adsorption unit becomes equal to or less than the set appropriate upper limit value. Is configured to return the operating state of the reforming unit to the reference operating state.

That is, if the maximum value of the off-gas storage amount that repeatedly increases or decreases becomes equal to or less than the set appropriate upper limit value after operating the reforming unit in the off-gas consumption increasing operating state, the operating state of the reforming unit is the reference operation. It will be returned to the state.

In this way, when the maximum value of the off-gas storage amount becomes equal to or less than the set appropriate upper limit value, the operating state of the reforming unit is returned to the standard operating state. Therefore, the off-gas stored in the off-gas tank is removed. It is possible to suppress consumption more than necessary.

In short, according to the further characteristic configuration of the hydrogen production apparatus of the present invention, it is possible to suppress the consumption of off-gas stored in the off-gas tank more than necessary.

A further characteristic configuration of the hydrogen production apparatus of the present invention is that the off-gas amount detecting unit is configured to detect the internal pressure of the off-gas tank.

That is, since the off-gas amount detecting unit detects the internal pressure of the off-gas tank as the off-gas storage amount of the off-gas stored in the off-gas tank, the off-gas storage amount can be detected with a simple configuration.

That is, for example, the flow rate of the off-gas collected in the off-gas tank is integrated to obtain the integrated recovery amount of the off-gas collected in the off-gas tank, and the flow rate of the off-gas discharged from the off-gas tank is integrated and discharged from the off-gas tank. It is conceivable to obtain the accumulated off-gas emission amount and subtract the integrated emission amount from the accumulated recovery amount to detect the off-gas storage amount, but in this case, the configuration for detecting the off-gas storage amount becomes complicated.

On the other hand, since the internal pressure of the off-gas tank is detected as the off-gas storage amount, the off-gas storage amount can be detected with a simple configuration.

In short, according to the further characteristic configuration of the hydrogen production apparatus of the present invention, the off-gas storage amount can be detected with a simple configuration.

Overall view showing hydrogen production equipment Schematic diagram showing the pressure fluctuation adsorption part The figure which shows the operation cycle of a pressure fluctuation adsorption part Explanatory drawing showing the operating state of the pressure fluctuation suction part Explanatory drawing showing the operating state of the pressure fluctuation suction part Explanatory drawing showing the operating state of the pressure fluctuation suction part

[Embodiment]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
(Overall configuration of hydrogen production equipment)
As shown in FIG. 1, the hydrogen production apparatus includes a reforming section A that reforms a raw material gas G, which is a hydrocarbon gas such as natural gas or naphtha, into a reforming gas having a large hydrogen component, and the reforming section. It is discharged from the pressure fluctuation adsorption unit B provided with the adsorption tower 1 for adsorbing the adsorption target component other than the hydrogen component from the reforming gas from A to the adsorbent to generate the product gas H, and the pressure fluctuation adsorption unit B. An off-gas tank T for recovering off-gas and a control unit M for controlling the operation of the reforming unit A and the pressure fluctuation adsorption unit B are provided.

The reforming unit A includes a steam mixing unit J for mixing steam so that the ratio of the number of moles of steam mixed with the raw material gas G to the number of moles of carbon in the raw material gas is the target ratio (S / C). A reforming reaction tube 2 as a reforming reaction unit that reforms the gas G into a reformed gas containing a large amount of hydrogen by steam reforming treatment, and a combustion unit that heats the reforming reaction tube 2 to a reforming reaction temperature. The burner 3 as is provided.
An off-gas supply path 4 for supplying the off-gas stored in the off-gas tank T to the burner 3 is provided, and an air supply path 5 for supplying combustion air to the burner 3 is provided.

A raw material gas supply line 7 for transporting the raw material gas G to the desulfurization device 6 is provided, and a mixing section transfer line 9 for transporting the raw material gas G desulfurized by the desulfurization device 6 to the water mixing section 8 is provided.
The water mixing unit 8 is configured to supply water conveyed through the water supply line 10 and mix it with the raw material gas G after the desulfurization treatment.

An evaporation transfer line 12 is provided in which the raw material gas G mixed with water is transferred toward the heat exchange unit 11 for evaporation in the water mixing unit 8, and the water mixed with the raw material gas G is transferred to the heat exchange unit 11 for evaporation. It is configured to be heated to become steam.
Incidentally, in the present embodiment, the steam mixing unit J is configured with the water mixing unit 8 and the heat exchange unit 11 for evaporation as the main units.

Then, the raw material gas G heated so as to contain water vapor (a state in which water vapor is mixed) in the heat exchange unit 11 for evaporation is conveyed to the reforming reaction tube 2 by the reaction tube transfer line 13. , It is configured to be reformed into a reformed gas K having a large amount of hydrogen by steam reforming treatment.
That is, the inside of the reforming reaction tube 2 is filled with a reforming catalyst, and as described above, it is heated to the reforming reaction temperature (for example, 750 ° C.) by the burner 3, and hydrogen is reformed by steam reforming. It is configured to reform into a reformed gas with many components.

By the way, in the present embodiment, the combustion gas of the burner 3 flows toward the heat exchange unit 11 for evaporation after heating the reforming reaction tube 2, heats the heat exchange unit 11 for evaporation, and then exhaust gas. It is configured to be discharged through the road 14.

A transformer transfer line 16 for transporting the reforming gas K from the reforming reaction tube 2 to the CO transformer 15 is provided, and carbon monoxide contained in the reforming gas K is converted into carbon dioxide by the CO transformer 15. It is configured to be reformed.
Then, the reformed gas K transformed by the CO transformer 15 is supplied to the pressure fluctuation adsorption unit B through the reformed gas supply line 17.
The reforming gas supply line 17 is provided with a water separation unit 18 including a water cooler 18a and a steam separator 18b, and is configured to remove excess water from the reforming gas K.

(Details of pressure fluctuation adsorption part)
The pressure fluctuation suction unit B of the present embodiment includes a first suction tower 1A, a second suction tower 1B, and a third suction tower 1C as the suction tower 1.
As shown in FIG. 2, the lower part of each of the three adsorption towers 1 provides a first supply branch path 21a and a second supply valve 20b provided with a first supply valve 20a to the reforming gas supply line 17. It is connected via a second supply branch path 21b provided and a third supply branch path 21c provided with a third supply valve 20c.

Each adsorption tower 1 is loaded and filled with an adsorbent that adsorbs a component to be adsorbed other than the hydrogen component from the reformed gas K.
The components to be adsorbed other than the hydrogen component are carbon dioxide, carbon monoxide, methane, nitrogen and the like, and carbon monoxide and methane are combustible components.

Further, the upper part of each of the three suction towers 1 has a first discharge branch path 22a provided with a first discharge valve 23a and a second discharge valve 23b provided with a second discharge valve 23b for the product gas discharge line 22. It is connected via a third discharge branch path 22c provided with a branch path 22b and a third discharge valve 23c.

Further, the upper part of each of the three suction towers 1 has a first pressure equalizing branch path 24a provided with a first pressure equalizing valve 25a and a second pressure equalizing branch provided with a second pressure equalizing valve 25b with respect to the pressure equalizing line 24. It is connected via a third pressure equalizing branch passage 24c provided with a road 24b and a third pressure equalizing valve 25c.
Further, a cleaning line 26 for flowing the product gas H flowing through the product gas discharge line 22 to the pressure equalizing line 24 is provided, and a cleaning valve 27 is provided in the cleaning line 26.

Further, the lower part of each of the three adsorption towers 1 has a first off-gas branch path 28a provided with a first off-gas valve 29a and a second off-gas branch provided with a second off-gas valve 29b with respect to the off-gas discharge line 28. The road 28b is connected via a third off-gas branch passage 28c provided with a third off-gas valve 29c, and the off-gas discharge line 28 is connected to the off-gas tank T.

As shown in FIG. 3, the pressure fluctuation adsorption unit B is controlled by the control unit M to perform an adsorption step, a pressure equalization (discharge) step, a depressurization step, a cleaning step, and a pressure equalization (in each of the three adsorption towers 1). It is configured to generate a product gas H containing hydrogen gas with high purity from the reformed gas K by repeatedly performing an operation cycle consisting of a receiving) step and a boosting step in a state where the operating phases are different from each other. ..

That is, the first unit cycle in which the first adsorption tower 1A performs the adsorption step, the second unit cycle in which the second adsorption tower 1B performs the adsorption step, and the third unit cycle in which the third adsorption tower 1C performs the adsorption step are repeatedly executed. It is configured as follows.

To add an explanation, in the first unit cycle in which the first adsorption tower 1A performs the adsorption step, the first supply valve 20a and the first discharge valve 23a are opened to adsorb the components to be adsorbed contained in the reforming gas K. The adsorption step of adsorbing is executed (see FIGS. 4 to 6), and the product gas H is discharged from the first adsorption tower 1A to the product gas discharge line 22.

At the initial stage of the first unit cycle, the second pressure equalizing valve 25b of the second suction tower 1B and the third pressure equalizing valve 25c of the third suction tower 1C are opened to adsorb the internal gas of the third suction tower 1C to the second. The pressure equalizing step of supplying to the tower 1B will be performed (see FIG. 4).
This pressure equalizing step corresponds to the pressure equalizing (discharge) step in the third adsorption tower 1C, and corresponds to the pressure equalizing (accepting) step in the second adsorption tower 1B.

In the second suction tower 1B, when the pressure equalizing step is completed, the second pressure equalizing valve 25b is closed and the second discharge valve 23b is opened to release the product gas H discharged from the first suction tower 1A. The boosting step to be introduced is executed until the end of the first unit cycle (see FIGS. 5 and 6).

In the third adsorption tower 1C, when the pressure equalizing step is completed, the third pressure equalizing valve 25c is closed and the third off-gas valve 29c is opened to release the internal gas of the third adsorption tower 1C to the off-gas discharge line 28. (See FIG. 5), the third off-gas valve 29c is left open, the third pressure equalizing valve 25c and the cleaning valve 27 are opened, and the product gas H is discharged from the cleaning line 26. A flushing cleaning step is performed (see FIG. 6).

Further, the off gas discharged to the off gas discharge line 28 in the depressurizing step and the cleaning step is recovered in the off gas tank T and then supplied to the burner 3 of the reforming section A through the off gas supply path 4.
The off-gas contains carbon monoxide, methane and hydrogen as combustible components.

The amount of off-gas stored in the off-gas tank T will repeatedly increase or decrease as the pressure fluctuation adsorption unit B operates.
That is, in each of the first unit cycle, the second unit cycle, and the third unit cycle, the off-gas storage amount rapidly increases when the depressurization step is started, and then the off-gas storage amount also increases when the cleaning step is performed thereafter. However, when the pressure equalization step is performed, the off-gas storage amount is repeatedly increased or decreased while the off-gas storage amount is gradually reduced.

Incidentally, as an off-gas amount detecting unit for detecting the off-gas amount stored in the off-gas tank T, a pressure sensor PS for detecting the internal pressure of the off-gas tank T is provided.
Further, as shown in FIG. 1, a supply line 19 for supplying the reformed gas K from the reformed gas supply line 17 to the off-gas tank T is provided when the amount of off-gas stored in the off-gas tank T is insufficient. , A supply valve 19A for opening and closing the supply line 19 is provided.
When the pressure sensor PS detects that the off-gas storage amount stored in the off-gas tank T is insufficient, the supply valve 19A is opened and the off-gas storage amount stored in the off-gas tank T becomes the set reference amount. The reforming gas K is configured to be replenished to the off-gas tank T until it is detected by the pressure sensor PS.

In the first unit cycle in which the first adsorption tower 1A performs the adsorption step, as described above, the pressure equalizing (accepting) step and the boosting step are sequentially executed for the second adsorption tower 1B, and the third adsorption tower 1C The pressure equalizing (discharge) process, the depressurizing process, and the cleaning process are sequentially executed.
The second unit cycle in which the second adsorption tower 1B performs the adsorption step and the third unit cycle in which the third adsorption tower 1C performs the adsorption step are the same as the first unit cycle in which the first adsorption tower 1A performs the adsorption step. In this embodiment, the detailed description of the second unit cycle and the third unit cycle will be omitted.

(Operation control of reforming part)
The raw material gas supply line 7 is provided with a raw material gas supply unit 30 that supplies the raw material gas G and can adjust the supply amount, and a raw material gas sensor 31 that detects the supply amount of the raw material gas G.
Then, the control unit M supplies the raw material gas G of the target raw material gas supply amount required for producing the product gas H of the target production amount based on the instruction information indicating the target production amount of the product gas H. , It is configured to control the operation of the raw material gas supply unit 30.
That is, the operation of the raw material gas supply unit 30 is controlled so that the supply amount of the raw material gas G detected by the raw material gas sensor 31 becomes the target raw material gas supply amount.

Incidentally, in the present embodiment, the flow rate at which the raw material gas supply unit 30 returns the compressor 30a for supplying the raw material gas G and a part of the raw material gas G supplied by the compressor 30a to the upstream side of the compressor 30a. It is configured to include a control valve 30b.

The water supply line 10 supplies water treated with pure water by the water treatment unit 32 to the water mixing unit 8, and the water supply line 10 is provided with a water supply pump 33 for supplying water and water supply. A water flow rate sensor 34 that detects the flow rate of water supplied through the line 10 and a water flow rate control valve 35 that adjusts the amount of water supply are provided.
The water supply pump 33 is equipped with a pressure control valve 33a that controls the water supply pressure to a set pressure.

Then, the control unit M sets the target ratio (S / C), which is the ratio of the number of moles of water vapor supplied to the raw material gas G to the number of moles of carbon in the raw material gas G, as the reference operation ratio (for example) in the reference operation state. , 3.0), it is configured to control the operation of the water flow control valve 35.
That is, in a state where the raw material gas G is supplied at the target raw material supply amount, the target water supply amount for setting the target ratio (S / C) to the standard operating ratio (for example, 3.0) in the standard operating state is set. It is configured to control the operation of the water flow rate control valve 35 so that the flow rate detected by the water flow rate sensor 34 becomes the target water supply amount.

A temperature sensor TS for detecting the internal temperature of the reforming reaction tube 2 is provided.
The off-gas supply path 4 is provided with an off-gas flow rate sensor 36 for detecting the off-gas flow rate and an off-gas flow rate control valve 37 for adjusting the off-gas flow rate.
The air supply path 5 is provided with a blower 38 that supplies air and can adjust the supply amount, and an air flow rate sensor 39 that detects the amount of air flowing through the air supply path 5.

Then, the control unit M sets the temperature for the reforming reaction of the reforming reaction tube 2 detected by the temperature sensor TS to the reference target temperature (for example, 750 ° C.) in the reference operating state, so that the temperature sensor TS and the reference target The off-gas flow rate control valve 37 is controlled so that the off-gas flow rate detected by the off-gas flow rate sensor 36 becomes the off-gas target amount by obtaining the off-gas target amount to be supplied to the burner 3 based on the temperature. It is configured.

Further, the control unit M obtains the target combustion air amount required to burn the off-gas target amount of off-gas, and the blower 38 so that the air amount detected by the air flow sensor 39 becomes the target air amount. It is configured to control the operation of.

(About off-gas consumption increase operation)
When the maximum value of the off-gas storage amount that repeatedly increases or decreases with the operation of the pressure fluctuation adsorption unit B is equal to or less than the set appropriate upper limit value, the control unit M operates the reforming unit A in the reference operating state and operates the modified unit A. When the maximum value of the off-gas storage amount is larger than the set appropriate upper limit value, the operating state of the reforming unit A is consumed by the burner 3 with the processing amount of the raw material gas G maintained at the same processing amount. It is configured to change the off-gas consumption to an off-gas consumption increasing operating state that increases the amount consumed in the standard operating state.

Further, when the maximum value of the off-gas storage amount that is repeatedly increased or decreased by the operation of the pressure fluctuation adsorption unit becomes equal to or less than the set appropriate upper limit value, the operation state of the reforming unit A is changed to the reference operation state. It is configured to return to.

That is, in the present embodiment, as described above, the pressure sensor PS for detecting the internal pressure of the off-gas tank is provided as the off-gas amount detecting unit for detecting the off-gas amount stored in the off-gas tank T.
Since the internal pressure of the off-gas tank T increases or decreases as the off-gas storage amount increases or decreases in each of the first unit cycle, the second unit cycle, and the third unit cycle, it is stored in the off-gas tank T. The amount of off-gas stored is detected by the pressure sensor PS as the internal pressure of the off-gas tank.

Then, in any of the first unit cycle, the second unit cycle, and the third unit cycle, the maximum value of the internal pressure of the off-gas tank T detected by the pressure sensor PS is set to correspond to the setting appropriate upper limit value. When the pressure is equal to or lower than the upper limit pressure, the control unit M operates the reforming unit A in the reference operating state.
Then, in any of the first unit cycle, the second unit cycle, and the third unit cycle, the maximum value of the internal pressure of the off-gas tank T detected by the pressure sensor PS is set corresponding to the set appropriate upper limit value. When the pressure becomes higher than the upper limit pressure, the control unit M keeps the operating state of the reforming unit A at the same processing amount of the raw material gas G, and the off gas consumed by the burner 3. The consumption amount will be changed to the off-gas consumption increase operation state in which the consumption amount is increased more than the amount consumed in the standard operation state.

Further, after changing to the off-gas consumption increasing operating state, the internal pressure of the off-gas tank T detected by the pressure sensor PS in any of the first unit cycle, the second unit cycle, and the third unit cycle. When the maximum value becomes equal to or less than the set upper limit pressure, the control unit M returns the operating state of the reforming unit A to the reference operating state.

In the present embodiment, the number of moles of water vapor supplied to the raw material gas G while the control unit M maintains the state of heating the reforming reaction tube 2 to the reference target temperature (for example, 750 ° C.) with the burner 3. The target ratio (S / C), which is the ratio to the number of moles of carbon in the raw material gas, is larger than the standard operating ratio (for example, 3.0) in the standard operating state in the off gas consumption increasing operating state. It is configured to change to an increasing ratio (eg, 3.1).
As a result, since the target ratio (S / C) has increased, the temperature of the reforming reaction tube 2 is raised to the reference target temperature (for example, 750 ° C.) as the temperature for the reforming reaction by heating the burner 3. The required amount of off-gas increases, which increases the off-gas consumption of the off-gas tank T.

Therefore, immediately after reducing the supply amount of the raw material gas G in order to reduce the production amount of the product gas H, the internal pressure of the off-gas tank T detected by the pressure sensor PS becomes higher than the set upper limit pressure. In this case, by changing to the off-gas consumption increasing operating state, the consumption of the off-gas stored in the off-gas tank T is increased, and the off-gas stored in the off-gas tank T is not discharged to the outside. Off-gas can be consumed.

If the internal pressure of the off-gas tank T detected by the pressure sensor PS becomes equal to or less than the set upper limit pressure after changing to the off-gas consumption increasing operating state, the operating state of the reforming unit A is used as the reference operation. By returning to the state and reducing the consumption of the off-gas, it is possible to avoid the situation where the reformed gas K is replenished in the off-gas tank T.

[Another Embodiment]
Next, another embodiment will be described, but this other embodiment shows another embodiment of the off-gas consumption increasing operation, and the other embodiments are the same as those of the above embodiment. Only the different parts will be described.

That is, in this other embodiment, the control unit M sets the target ratio (S / C), which is the ratio of the number of moles of water vapor supplied to the raw material gas G to the number of moles of carbon in the raw material gas G, as the reference operation ratio (S / C). For example, the temperature for the reforming reaction in which the temperature of the reforming reaction tube 2 is raised by heating the burner 3 while being maintained at 3.0) is set to the reference target temperature in the reference operating state (for example, in the off-gas consumption increasing operating state). , 750 ° C) and higher off-gas consumption increase target temperature (eg, 752 ° C).

As a result, the temperature for the reforming reaction of the reforming reaction tube 2 raised by heating the burner 3 is higher than the reference target temperature (for example, 750 ° C.) in the reference operating state, and the off-gas consumption increase target temperature (for example, 752). By changing to (° C.), the amount of off-gas required to raise the temperature of the reforming reaction tube 2 to the target temperature for increasing off-gas consumption (for example, 752 ° C.) by heating the burner 3 increases, and the off-gas tank increases. The off-gas consumption of T will increase.

Therefore, immediately after reducing the supply amount of the raw material gas G in order to reduce the production amount of the product gas H, the internal pressure of the off-gas tank T detected by the pressure sensor PS becomes higher than the set upper limit pressure. In this case, by changing to the off-gas consumption increasing operating state, the consumption of the off-gas stored in the off-gas tank T is increased, and the off-gas stored in the off-gas tank T is not discharged to the outside. Off-gas can be consumed.

If the internal pressure of the off-gas tank T detected by the pressure sensor PS becomes equal to or less than the set upper limit pressure after changing to the off-gas consumption increasing operating state, the operating state of the reforming unit A is used as the reference operation. By returning to the state and reducing the consumption of the off-gas, it is possible to avoid the situation where the reformed gas K is replenished in the off-gas tank T.

[Other Other Embodiments]
Next, other other embodiments are listed.
(1) In the above embodiment, as the pressure fluctuation adsorption unit B, the one provided with three adsorption towers 1 is exemplified, but in the present invention, the pressure fluctuation adsorption unit B is provided with two or four or more adsorption towers 1. It can also be applied to the case where the configuration is configured to include.

(2) In the above embodiment, the pressure fluctuation suction unit B is configured to perform a cleaning step, but in the present invention, the pressure fluctuation suction unit B uses a vacuum pump instead of the cleaning step. It can also be applied to the case of performing a suction step of sucking the inside of the suction tower 1.

(3) In the above embodiment, an example is exemplified in which the steam mixing unit J is configured to mix water with the raw material gas G and then evaporate the mixed water in the heat exchange unit 11 for evaporation. However, the steam mixing unit J may be configured to mix the steam generated in advance with the raw material gas G.

(4) In the above embodiment, a case where a pressure sensor PS for detecting the internal pressure of the off-gas tank is provided as an off-gas amount detecting unit for detecting the off-gas amount stored in the off-gas tank T is illustrated. As a part, the flow rate of off-gas collected in the off-gas tank T is integrated to obtain the integrated recovery amount of off-gas collected in the off-gas tank T, and the flow rate of off-gas discharged from the off-gas tank T is integrated to turn off. It may be carried out in a form in which the integrated discharge amount of off-gas discharged from the gas tank T is obtained, and the integrated discharge amount is subtracted from the integrated recovery amount to detect the accumulated off-gas amount.

The configuration disclosed in the above embodiment (including another embodiment, the same shall apply hereinafter) can be applied in combination with the configuration disclosed in other embodiments as long as there is no contradiction. The embodiments disclosed in the present specification are examples, and the embodiments of the present invention are not limited thereto, and can be appropriately modified without departing from the object of the present invention.

1 Adsorption tower 2 Remodeling reaction unit 3 Combustion unit 4 Off gas supply path A Remodeling unit B Pressure fluctuation adsorption unit G Raw material gas H Product gas K Remodeling gas M Control unit PS Off gas amount detection unit T Off gas tank

Claims (4)

A steam mixing section that mixes steam so that the ratio of the number of moles of steam mixed with the raw material gas, which is a hydrocarbon gas, to the number of moles of carbon in the raw material gas is the target ratio, and the raw material gas is steam reformed. A reforming reaction unit that reforms into a reforming gas containing a large amount of hydrogen components, a reforming unit having a combustion unit that heats the reforming reaction unit to a reforming reaction temperature, and the reforming unit from the reforming unit. A pressure fluctuation adsorption unit equipped with an adsorption tower that adsorbs an adsorption target component other than the hydrogen component from the gas to an adsorbent to generate a product gas, an off gas tank that recovers the off gas discharged from the pressure fluctuation adsorption unit, and the said. A hydrogen production apparatus provided with an off-gas supply path for supplying the off-gas stored in the off-gas tank to the combustion unit, and a control unit for controlling the operation of the reforming unit and the pressure fluctuation adsorption unit.
An off-gas amount detection unit for detecting the off-gas storage amount of the off-gas stored in the off-gas tank is provided.
When the control unit repeatedly increases or decreases with the operation of the pressure fluctuation adsorption unit and the maximum value of the off-gas storage amount is equal to or less than the set appropriate upper limit value, the reforming unit is operated in the reference operating state and When the maximum value is larger than the set appropriate upper limit value, the operating state of the reforming unit is consumed in the combustion unit while the processing amount of the raw material gas is maintained at the same processing amount. It is configured to change the off-gas consumption to an off-gas consumption increasing operating state that increases the amount consumed in the reference operating state.
A hydrogen production apparatus in which the control unit changes the reforming reaction temperature to an off-gas consumption increase target temperature higher than the reference target temperature in the reference operation state in the off-gas consumption increase operation state . A steam mixing section that mixes steam so that the ratio of the number of moles of steam mixed with the raw material gas, which is a hydrocarbon gas, to the number of moles of carbon in the raw material gas is the target ratio, and the raw material gas is steam reformed. A reforming reaction unit that reforms into a reforming gas containing a large amount of hydrogen components, a reforming unit having a combustion unit that heats the reforming reaction unit to a reforming reaction temperature, and the reforming unit from the reforming unit. A pressure fluctuation adsorption unit equipped with an adsorption tower that adsorbs an adsorption target component other than the hydrogen component from the gas to an adsorbent to generate a product gas, an off gas tank that recovers the off gas discharged from the pressure fluctuation adsorption unit, and the said. A hydrogen production apparatus provided with an off-gas supply path for supplying the off-gas stored in the off-gas tank to the combustion unit, and a control unit for controlling the operation of the reforming unit and the pressure fluctuation adsorption unit.
An off-gas amount detection unit for detecting the off-gas storage amount of the off-gas stored in the off-gas tank is provided.
When the control unit repeatedly increases or decreases with the operation of the pressure fluctuation adsorption unit and the maximum value of the off-gas storage amount is equal to or less than the set appropriate upper limit value, the reforming unit is operated in the reference operating state and When the maximum value is larger than the set appropriate upper limit value, the operating state of the reforming unit is consumed in the combustion unit while the processing amount of the raw material gas is maintained at the same processing amount. It is configured to change the off-gas consumption to an off-gas consumption increasing operating state that increases the amount consumed in the reference operating state.
A hydrogen production apparatus in which the control unit changes the target ratio to an off-gas consumption increase ratio that is larger than the reference operation ratio in the reference operation state in the off-gas consumption increase operation state . When the maximum value of the off-gas storage amount that the control unit repeatedly increases or decreases with the operation of the pressure fluctuation adsorption unit becomes equal to or less than the set appropriate upper limit value, the operating state of the reforming unit is determined as the reference. The hydrogen production apparatus according to claim 1 or 2 , which is configured to return to an operating state . The hydrogen production apparatus according to any one of claims 1 to 3 , wherein the off-gas amount detecting unit is configured to detect the internal pressure of the off-gas tank .

Images