JP7006886B2 - Hydrogen production equipment and hydrogen production method - Google Patents

Description

The present invention relates to a hydrogen production apparatus and a hydrogen production method for producing hydrogen gas from ammonia.

Hydrogen gas is expected to be the ultimate source of clean energy. For example, hydrogen gas is used as a fuel gas for a fuel cell.
Ammonia is also used as a raw material for this hydrogen gas. Ammonia is attracting attention as a chemical substance (hydrogen carrier) that facilitates the storage and transportation of hydrogen. Ammonia is easily liquefied by compressing it at room temperature of 1 MPa or less. Liquid ammonia is an extremely excellent hydrogen carrier having an extremely high weight hydrogen density of 17.8% by mass and a volumetric hydrogen density of 1.5 to 2.5 times that of liquid hydrogen.

By the way, when hydrogen gas contains undecomposed ammonia as an impurity, the ammonia adversely affects the electrolyte membrane and the catalyst layer in the fuel cell. Therefore, after decomposing ammonia to obtain an ammonia decomposing gas, the decomposing gas is introduced into an ammonia adsorbent to remove ammonia.

For example, Patent Document 1 discloses a technique in which ammonia is supplied to an ammonia decomposition apparatus to decompose it into hydrogen (H ₂ ) and nitrogen (N ₂ ), and then supplied to an ammonia adsorber to remove unreacted ammonia. ing. Further, Patent Document 1 also describes that it can be used as hydrogen by separating a gas other than hydrogen from the gas after removing unreacted ammonia with an ammonia adsorber. Further, Patent Document 1 also describes that a plurality of ammonia adsorbers are installed in parallel, and when one ammonia adsorber adsorbs ammonia, another ammonia adsorber repeatedly desorbs and desorbs ammonia (switching method). Has been done.

Japanese Unexamined Patent Publication No. 2015-059075

Patent Document 1 describes that hydrogen is produced by separating hydrogen from a gas after removing unreacted ammonia with an ammonia adsorber. However, there is no specific description on how to utilize off-gas after removing hydrogen.
The present invention relates to a hydrogen production apparatus and a hydrogen production method capable of effectively utilizing the off-gas.

As a result of diligent studies, the present inventors used the off-gas after removing unreacted ammonia from the ammonia decomposition gas and further separating hydrogen to regenerate the ammonia adsorbent stored in the ammonia adsorbent and desorbed it. It has been found that the off-gas can be effectively used by burning the off-gas containing ammonia and utilizing the heat of combustion.
That is, the present invention relates to the following [1] to [25].

[1] Connected to an ammonia supply device and an ammonia decomposition device which is connected to the ammonia supply device and decomposes ammonia to generate a decomposition gas containing hydrogen, nitrogen and unreacted ammonia, and the ammonia decomposition device. A decomposition gas cooling device that cools the decomposition gas, and an ammonia adsorption device that is connected to the decomposition gas cooling device and adsorbs and removes unreacted ammonia from the decomposition gas and discharges the gas after removing the ammonia. A hydrogen recovery device that is connected to the ammonia adsorbing device and separates hydrogen from the ammonia after removing the ammonia and discharges the remaining off-gas, and a heating device that heats the ammonia decomposition device. The ammonia adsorbing device has a plurality of ammonia adsorbers arranged in parallel, and the decomposing gas from the decomposing gas cooling device is applied to any part of the plurality of ammonia adsorbers. A hydrogen production device that can be supplied and is connected to the hydrogen recovery device, the off-gas heating device for heating the off-gas, and one end connected to the off-gas heating device, and the other end is the plurality of ammonia. An off-gas flow path that is connected to an adsorbent and supplies the off-gas to a used ammonia adsorber to regenerate the ammonia adsorbent, and is connected to a plurality of the ammonia adsorbers and the used ammonia. A combustion reaction device that is connected to the adsorbent reclaimed gas flow path through which the adsorbent regenerated gas flowing out of the adsorber flows and the adsorbent regenerated gas flow path, and burns the adsorbent regenerated gas to discharge the combustion gas. A hydrogen production device having a combustion gas flow path having one end connected to the combustion reaction device and the other end connected to the heating device.

According to the hydrogen production apparatus, hydrogen can be produced from ammonia, and the off gas flowing out from the hydrogen recovery apparatus can be effectively used as a regenerating gas for the ammonia adsorbent in the ammonia adsorber. Further, the off-gas flowing out from the hydrogen recovery device contains nitrogen and hydrogen, and the adsorbent regeneration gas after the off-gas is used for regeneration of the ammonia adsorbent contains nitrogen, hydrogen and ammonia. A high-temperature combustion gas can be obtained by burning the adsorbent regenerated gas containing nitrogen, hydrogen, and ammonia in a combustion reactor, and the high-temperature combustion gas can be used to sufficiently heat the ammonia decomposition device. can.

[2] The decomposition gas cooling device and the off-gas heating device are the same heat exchanger, and heat can be exchanged between the decomposition gas flowing out of the ammonia decomposition device and the off-gas flowing out of the hydrogen recovery device. The hydrogen production apparatus according to the above [1].
With this heat exchanger, the heat of the decomposition gas can be imparted to the off-gas, and the thermal efficiency is improved.

[3] The hydrogen production apparatus according to the above [1] or [2], wherein one end is connected to the heating device and the other end is connected to the adsorbent recycled gas flow path.
By using the circulating gas flow path, a part or all of the combustion gas used for heating the ammonia decomposition device is mixed with the above-mentioned adsorbent regenerated gas and burned, and then used again for heating the ammonia decomposition device. can do. As a result, the flow rate of the combustion gas supplied to the ammonia decomposition device can be increased, thereby improving the thermal efficiency.
Further, since the combustion gas flowing out from the combustion reaction device has already been burned, the content of combustible gas such as hydrogen and ammonia is small. Then, the combustion gas is used as a circulating gas after being used for heating the ammonia decomposition device, mixed with the above-mentioned adsorbent reclaimed gas, and burned in the combustion reaction device. This makes it possible to adjust the gas supplied to the combustion reactor so that it does not fall within the hydrogen explosion range.

[4] The hydrogen production apparatus according to the above [3], wherein an oxygen supply device is connected to one or both of the adsorbent regenerated gas flow path and the circulating gas flow path.
By supplying an oxygen-containing gas from the oxygen supply device and supplying the mixed gas after adjusting the composition by mixing the above-mentioned adsorbent regenerated gas, circulating gas, and oxygen-containing gas to the combustion reaction device, the combustion reaction device The gas can be burned almost completely inside.

[5] A water flow path that intersects the circulating gas flow path, a heat exchanger for heating hot water installed at the intersection of the circulating gas flow path and the water flow path, and heating provided at the downstream end of the water flow path. The hydrogen production device according to the above [3] or [4], which has a water supply device and heats the ammonia supply device using the heated water flowing out from the heated water supply device.
By discharging hot water from the heated water supply device to the above-mentioned ammonia supply device, the liquid ammonia in the ammonia supply device can be vaporized.

[6] In the above [5], a drain pot for removing water in the circulating gas flowing through the circulating gas flow path is provided downstream of the hot water heating heat exchanger in the circulating gas flow path. The hydrogen production apparatus described.
By removing the water in the drain pot, the water generated in the combustion reaction device can be discharged from the circulating gas system.

[7] The first point of the circulating gas flow path located upstream of the hot water heating heat exchanger and the second point located downstream of the drain pot intersect to form an intersection. In the above [6], a portion of the circulating gas flow path between the first point and the second point is an annular flow path, and a heat exchanger for circulating gas is installed at the intersection. The hydrogen production apparatus described.
[8] The hydrogen production apparatus according to the above [6] or [7], which has a circulating gas circulator downstream of the drain pot in the circulating gas flow path, for example, an annular flow path.

[9] The hydrogen production apparatus according to the above [7], wherein a gas waste flow path for discharging a part or all of the circulating gas is connected in the middle of the circulating gas flow path, for example, the annular flow path. ..
By discharging a part or all of the circulating gas from the gas waste flow path, the composition and flow rate of the gas supplied to the combustion reaction device can be adjusted.

[10] The gas waste flow path includes a first gas waste flow path whose one end is connected to the annular flow path, and an auxiliary ammonia adsorption device connected to the other end of the first gas waste flow path. The hydrogen production according to the above [9], which is connected to the auxiliary ammonia adsorbing device and has an ammonia abatement facility provided with a second gas waste flow path for flowing gas discharged from the auxiliary ammonia adsorbing device. Device.
By detoxifying the ammonia in the gas with the ammonia abatement device, the gas with less environmental load can be discharged to the outside of the system.

[11] The auxiliary ammonia adsorber has a plurality of auxiliary ammonia adsorbers arranged in parallel, and the upstream end of the first gas waste flow path is connected to the annular flow path and is downstream. The end branches to form a first branch flow path and is connected to the plurality of auxiliary ammonia adsorbers, and the upstream end of the second gas waste flow path branches to become a second branch flow path. It is connected to the plurality of auxiliary ammonia adsorbers, and the ammonia abatement facility is further connected to a regenerated gas supply device for supplying regenerated gas to the plurality of auxiliary ammonia adsorbents, and one end thereof is connected to the regenerated gas supply device. , The regenerated gas flow path is branched at the other end and connected to the second branch flow path, the regenerated gas heater provided in the middle of the regenerated gas flow path, and one end is branched. The desorbing gas flow path connected to the first branch flow path and the adsorbent desorption gas connected to the other end of the desorption gas flow path and discharged from each of the plurality of auxiliary ammonia adsorbers. An ammonia abatement facility having a waste gas combustion reactor that burns and flows out the combustion gas, and a return flow path that returns the combustion gas discharged from the waste gas combustion reactor to the second gas waste flow path. The hydrogen production apparatus according to the above [10].
[12] The hydrogen production apparatus according to the above [11], wherein the waste gas combustion reactor is the combustion reactor.
[13] The hydrogen production according to the above [11] or [12], which is provided in the return flow path and has a waste gas cooler for cooling the combustion gas flowing out of the waste gas combustion reactor. Device.
[14] The above [1] to the above [1] to have a hydrogen flow path connected to the hydrogen recovery device and flowing out hydrogen separated by the hydrogen recovery device, and a pressure control valve installed in the hydrogen flow path. The hydrogen production apparatus according to any one of [13].
The pressure control valve can adjust the pressure of the hydrogen recovery device, the ammonia adsorption device, and the ammonia decomposition device.

[15] The above-mentioned [1] to [14], which has an ammonia flow path connecting the ammonia supply device and the ammonia decomposition device, and a flow rate control valve installed in the ammonia flow path. Hydrogen production equipment.
The flow rate control valve can control the flow rate of ammonia supplied from the ammonia supply device to the ammonia decomposition device.

[16] It has a heat exchanger for heating ammonia installed in the ammonia flow path, and a decomposition gas flow path connecting the ammonia decomposition device and the ammonia adsorption device, and the decomposition gas flow path of the decomposition gas flow path. The decomposition gas cooling device is installed on the upstream side of the decomposition gas flow path on the upstream side of the installation position of the ammonia heating heat exchanger. The hydrogen production apparatus according to [15].

[17] It has a decomposition gas flow path connecting the ammonia decomposition device and the plurality of ammonia adsorbents, and a gas flow path after removing ammonia connecting the plurality of ammonia adsorbents and the hydrogen recovery device. The decomposition gas cooling device is installed in the middle of the decomposition gas flow path, and the decomposition gas flow path and the gas flow path after removing ammonia do not have a pressurizing device. ] The hydrogen production apparatus according to any one of.
As described above, since the pressurizing device is not provided, the equipment cost and the operating cost are reduced.

[18] A hydrogen production method using the hydrogen production apparatus according to any one of the above [1] to [17], wherein the ammonia from the ammonia supply device is circulated to the ammonia decomposition device to decompose the ammonia. Then, in the ammonia decomposition step of generating the decomposition gas containing hydrogen, nitrogen and unreacted ammonia, the decomposition gas flowing out of the ammonia decomposition apparatus is circulated to the decomposition gas cooling apparatus to be cooled, and then the plurality of said. Ammonia adsorption step in which unreacted ammonia is adsorbed and removed from the decomposed gas to obtain a gas after removing the ammonia, and the ammonia flowing out from the part of the plurality of ammonia adsorbers is distributed to a part of the ammonia adsorber. A hydrogen recovery step in which the removed gas is circulated to the hydrogen recovery device to separate hydrogen from the ammonia removed gas and flow out, and the remaining off gas is discharged, and the off gas flowing out from the hydrogen recovery device is used. The off-gas heating device, the ammonia adsorber regeneration step of regenerating the ammonia adsorber by circulating it to a part or all of the rest of the plurality of ammonia adsorbers, and the adsorbent regenerating gas flowing out from the ammonia adsorber. A hydrogen production method for carrying out a heating step of an ammonia decomposition device, which is distributed to the combustion reaction device, the combustion gas flow path, and the heating device to heat the ammonia decomposition device.

According to the hydrogen production apparatus, hydrogen can be produced from ammonia, and the off gas flowing out from the hydrogen recovery apparatus can be effectively used as a regenerating gas for the ammonia adsorbent in the ammonia adsorber. Further, the off-gas flowing out from the hydrogen recovery device contains nitrogen and hydrogen, and the adsorbent regeneration gas after the off-gas is used for regeneration of the ammonia adsorbent contains nitrogen, hydrogen and ammonia. A high-temperature combustion gas can be obtained by burning the adsorbent regenerated gas containing nitrogen, hydrogen, and ammonia in a combustion reactor, and the high-temperature combustion gas can be used to sufficiently heat the ammonia decomposition device. can.

[19] The hydrogen according to the above [18], wherein the off-gas heating device is the decomposition gas cooling device, and the heat of the decomposition gas is imparted to the off-gas by the decomposition gas cooling device to heat the off-gas. Production method.
With this heat exchanger, the heat of the decomposition gas can be imparted to the off-gas, and the thermal efficiency is improved.

[20] One end has a circulating gas flow path connected to the heating device and the other end connected to the adsorbent regenerated gas flow path, and the combustion gas is used in the combustion gas flow path and the heating device. And, it is circulated to the adsorbent reclaimed gas flow path through the circulating gas flow path to form a mixed gas with the adsorbent regenerated gas, and the mixed gas is circulated to the combustion reaction device to be burned. ] Or [19].
By using the circulating gas flow path, a part or all of the combustion gas used for heating the ammonia decomposition device is mixed with the above-mentioned adsorbent regenerated gas and burned, and then used again for heating the ammonia decomposition device. can do. As a result, the flow rate of the combustion gas supplied to the ammonia decomposition device can be increased, thereby improving the thermal efficiency.
Further, since the combustion gas flowing out from the combustion reaction device has already been burned, the content of combustible gas such as hydrogen and ammonia is small. Then, the combustion gas is used as a circulating gas after being used for heating the ammonia decomposition device, mixed with the above-mentioned adsorbent reclaimed gas, and burned in the combustion reaction device. This makes it possible to adjust the gas supplied to the combustion reactor so that it does not fall within the hydrogen explosion range.

[21] An oxygen supply device is connected to one or both of the adsorbent regenerated gas flow path and the circulating gas flow path, and the oxygen-containing gas supplied from the oxygen supply device is adsorbed with the circulating gas. The hydrogen production method according to the above [20], wherein the mixed gas is used as a mixed gas with the recycled material gas, and the mixed gas is circulated through the combustion reactor and burned.
By supplying an oxygen-containing gas from the oxygen supply device and supplying the mixed gas after adjusting the composition by mixing the above-mentioned adsorbent regenerated gas, circulating gas, and oxygen-containing gas to the combustion reaction device, the combustion reaction device The gas can be burned almost completely inside.

[22] A water flow path that intersects the circulating gas flow path, a heat exchanger for heating hot water installed at the intersection of the circulating gas flow path and the water flow path, and heating provided at the downstream end of the water flow path. It has a water supply device, and after flowing water or hot water to the hot water heating heat exchanger to make heated water, the heated water supply device supplies the heated water to the ammonia supply device to generate ammonia. The hydrogen production method according to the above [20] or [21].
By discharging the heated water from the heated water supply device to the above-mentioned ammonia supply device, the liquid ammonia in the ammonia supply device can be vaporized.

[23] A drain pot for removing water in the circulating gas is provided downstream of the hot water heating heat exchanger in the circulating gas flow path, and the circulating gas is transferred to the drain pot. The hydrogen production method according to the above [22], wherein after the water is circulated and the water is removed, the hydrogen is circulated to the combustion reactor together with the adsorbent regenerated gas and burned.
By removing the water in the drain pot, the water generated in the combustion reaction device can be discharged from the circulating gas system.

[24] It has a hydrogen flow path that is connected to the hydrogen recovery device and discharges hydrogen separated by the hydrogen recovery device, and a pressure control valve installed in the hydrogen flow path, and has the pressure. By controlling the control valve, each of the pressure P1 of the ammonia decomposition device, the pressure P2 of the ammonia adsorption device, and the pressure P3 of the hydrogen recovery device can be reduced.
P1 ≧ P2 ≧ P3
The hydrogen production method according to any one of the above [18] to [23], which is controlled to a predetermined pressure range satisfying the above relationship.
By setting P1 ≧ P2 ≧ P3 in this way, the pressurizing device becomes unnecessary, and the equipment cost and the operating cost are reduced.
By supplying an oxygen-containing gas from the oxygen supply device and supplying the mixed gas after adjusting the composition by mixing the above-mentioned adsorbent regenerated gas and the oxygen-containing gas to the combustion reaction device, the gas is supplied in the combustion reaction device. It can be burned almost completely.
[25] The hydrogen production apparatus is the hydrogen production apparatus according to any one of the above [10] to [13], and the gas flowing through the gas waste flow path is supplied to the ammonia abatement facility to remove ammonia. The hydrogen production method according to any one of [18] to [24], which comprises a harmful ammonia abatement step.

INDUSTRIAL APPLICABILITY According to the present invention, there is provided a hydrogen production apparatus and a hydrogen production method capable of effectively utilizing off-gas generated when ammonia is decomposed to produce hydrogen gas.

It is a schematic diagram of the hydrogen production apparatus which concerns on 1st Embodiment. It is a schematic diagram of the hydrogen production apparatus which concerns on 2nd Embodiment. It is a schematic diagram explaining the 1st operation using the hydrogen production apparatus of FIG. It is a schematic diagram of the hydrogen production apparatus which concerns on 3rd Embodiment. It is a schematic diagram of the hydrogen production apparatus which concerns on 4th Embodiment. It is a schematic diagram of the hydrogen production apparatus which concerns on 5th Embodiment. It is a schematic diagram of the hydrogen production apparatus which concerns on 6th Embodiment. It is a schematic diagram of the hydrogen production apparatus which concerns on 7th Embodiment.

[First Embodiment]
<Hydrogen production equipment>
FIG. 1 is a schematic view of the hydrogen production apparatus 1 according to the first embodiment.
The hydrogen production device 1 according to the present embodiment is connected to the ammonia supply device 2 and the ammonia supply device 2, and decomposes ammonia to generate a decomposition gas containing hydrogen, nitrogen and unreacted ammonia. It is connected to the ammonia decomposition device 3 and the decomposition gas decomposition device 3 and is connected to the decomposition gas cooling device 4a for cooling the decomposition gas and the decomposition gas cooling device 4a, and adsorbs and removes unreacted ammonia from the decomposition gas. It is connected to an ammonia adsorbing device 5 that discharges the gas after removing ammonia, which is mainly composed of hydrogen gas and nitrogen gas, and the ammonia adsorbing device 5, which separates hydrogen from the gas after removing ammonia and flows out. It has a hydrogen recovery device 6 for discharging the remaining off gas including hydrogen gas and nitrogen gas, and a heating device 8 for heating the ammonia decomposition device.

The ammonia adsorbing device 5 has a plurality of ammonia adsorbers 5a and 5b arranged in parallel, and the decomposition gas from the decomposition gas cooling device 4a can be arbitrarily used among the plurality of ammonia adsorbers 5a and 5b. It is said that it can be supplied to one side.
In the present embodiment, the number of ammonia adsorbers 5a and 5b is 2, but it may be 3 or more.

The hydrogen production device 1 is further connected to the hydrogen recovery device 6 and has an off-gas heating device 4b for heating the off-gas.
In the present embodiment, the off-gas heating device 4b and the decomposition gas cooling device 4a are the same heat exchanger (heat exchanger for cooling decomposition gas) 4, and the decomposition that flows out from the ammonia decomposition device 3. Heat exchange is possible between the gas and the off-gas flowing out of the hydrogen recovery device 6. This improves thermal efficiency.

The ammonia supply device 2 and the ammonia decomposition device 3 are connected to each other via an ammonia flow path 11.
The ammonia decomposition device 3 and the ammonia adsorption device 5 are connected via a decomposition gas flow path 12, and the decomposition gas cooling device 4a is connected in the middle of the decomposition gas flow path 12. The downstream end of the decomposition gas flow path 12 is branched into a plurality of (two in the present embodiment) branch flow paths 12a and 12b, and a plurality of (two in the present embodiment) ammonia adsorbers 5a. It is connected to all of 5b.
The ammonia adsorption device 5 and the hydrogen recovery device 6 are connected to each other via a gas flow path 14 after removing ammonia. After removing ammonia, the upstream end of the gas flow path 14 is branched into a plurality of (two in the present embodiment) branch flow paths 14a and 14b, and a plurality of (two in the present embodiment) ammonia adsorbers. It is connected to all of 5a and 5b. Each of the branch flow paths 12a and 12b and the branch flow paths 14a and 14b has an on-off valve.
The hydrogen production device 1 is further connected to the hydrogen recovery device 6 and has a hydrogen flow path 15 for flowing out hydrogen separated from the gas after removing ammonia and an off gas remaining after separating hydrogen from the gas after removing ammonia. It has a connection flow path 21 that flows out. One end (upstream end) of the connection flow path 21 is connected to the hydrogen recovery device 6, and the other end (downstream end) is connected to the off-gas heating device 4b (decomposition gas cooling heat exchanger 4).

Further, the hydrogen production device 1 has one end connected to the off-gas heating device 4b (decomposition gas cooling heat exchanger 4) and the other end connected to the plurality of ammonia adsorbents 5a and 5b, so that the off-gas can be used. An off-gas flow path 22 that supplies the used hydrogen adsorbents 5a and 5b to regenerate the ammonia adsorbent, and the used ammonia adsorbents 5a, which are connected to the plurality of the ammonia adsorbents 5a and 5b. It is connected to the adsorbent reclaimed gas flow path 23 through which the adsorbent regenerated gas (main components are hydrogen gas, nitrogen gas, and ammonia) flowing out from 5b and the adsorbent regenerated gas flow path 23, and is connected to the adsorbed material regenerated gas flow path 23. It has a combustion reaction device 7 that burns the recycled material gas and flows out the combustion gas, and a combustion gas flow path 24 having one end connected to the combustion reaction device 7 and the other end connected to the heating device 8.
The lower end of the off-gas flow path 22 is branched into a plurality of (two in the present embodiment) branch flow paths 22a and 22b, and a plurality of (two in the present embodiment) branch flow paths 14a and 14b. Of these, it is connected to the upstream side of the on-off valve. The upstream end of the adsorbent reclaimed gas flow path 23 is branched into a plurality of (two in the present embodiment) branch flow paths 23a and 23b, and a plurality of (two in the present embodiment) branch flow paths 12a. Of 12b, it is connected to the downstream side of the on-off valve. Each of the branch flow paths 22a and 22b and the branch flow paths 23a and 23b has an on-off valve.

In this embodiment, the decomposed gas flow path 12 and the ammonia-removed gas flow path 14 do not have a pressurizing device. This makes it possible to reduce equipment costs and operating costs. In this embodiment, the hydrogen production device 1 does not have a pressurizing device.
However, a pressurizing device may be provided in at least one of the decomposition gas flow path 12 and the gas flow path 14 after removing ammonia. As a result, the pressure of the ammonia decomposition device 3 can be lowered to improve the ammonia decomposition efficiency, and the pressure of the gas after removing the ammonia flowing into the hydrogen recovery device 6 can be increased to improve the hydrogen recovery efficiency. When the pressurizing device is provided, it is preferable to provide it only in the gas flow path 14 after removing ammonia among the decomposition gas flow path 12 and the gas flow path 14 after removing ammonia.

(Ammonia supply device 2)
In the present embodiment, the ammonia supply device 2 has a liquid ammonia tank.

(Ammonia decomposition device 3)
The ammonia decomposition device 3 houses an ammonia decomposition catalyst.
The ammonia decomposition catalyst is not particularly limited as long as it has catalytic activity in the ammonia decomposition reaction, but for example, base metal transition metals (iron, cobalt, nickel, molybdenum, etc.), rare earths (lanthanum, ruthenium, neodymium, etc.), etc. ), A catalyst containing a noble metal system (ruthenium, rhodium, iridium, palladium, platinum, etc.) as a composition. The base metal transition metal can be used as a single metal, an alloy, a nitride, a carbide, an oxide, or a composite oxide, and the rare earth system can be used as an oxide. Both the base metal transition metal and the rare earth system can be used. , Alumina, silica, magnesia, zirconia, titania and the like, and can be supported on a carrier having a high specific surface area. Further, the noble metal system can also be used by supporting it on a carrier having a high specific surface area such as alumina, silica, magnesia, zirconia, and titania. Further, the transition metal system and / or the rare earth system may be used by containing a small amount of the noble metal system. These catalysts may be used alone or in combination of two or more.

(Ammonia adsorption device 5)
The ammonia adsorbents 5a and 5b constituting the ammonia adsorber 5 house the ammonia adsorbent.
The ammonia adsorbent is not particularly limited as long as it can remove ammonia in the decomposition gas and is reproducible, and is preferably zeolite, activated carbon, alumina, silica, or a composite oxide.

(Hydrogen recovery device 6)
The hydrogen recovery device 6 is not particularly limited as long as it can separate hydrogen from the decomposition gas (main components: hydrogen gas and nitrogen gas) formed by decomposing ammonia. For example, the hydrogen recovery device 6 includes a pressure fluctuation adsorption separation device (PSA device), a temperature fluctuation adsorption separation device (TSA device), a hydrogen separation membrane device having a hydrogen separation membrane, and the like.

(Combustion reactor 7)
The combustion reaction device 7 is not particularly limited as long as it can burn the adsorbent regenerated gas flowing out from the regenerating ammonia adsorbents 5a and 5b. For example, a combustion reaction device that houses a combustion catalyst inside, direct combustion. Devices and the like can be mentioned.
Examples of the catalyst used in the combustion reactor include palladium, platinum and the like, but palladium is preferable from the viewpoint of cost. Further, in the case of a direct combustion device, it is also possible to mix kerosene, natural gas or the like with the regenerated gas of the adsorbent and burn it.
(Heating equipment 8)
The heating device 8 is a device that supplies the combustion gas from the combustion reaction device 7 to the periphery of the ammonia decomposition device 3 to heat the ammonia decomposition device 3.
Examples of the heating device 8 include a device that supplies combustion gas to a jacket that covers the periphery of the ammonia decomposition device 3, and a device in which a pipe through which the combustion gas passes is wound around the ammonia decomposition device 3.

<Hydrogen production method>
Next, an example of a hydrogen production method using the above-mentioned hydrogen production apparatus 1 will be described.
In the hydrogen production method according to the present embodiment, the first operation and the second operation, which will be described later, are repeated.

(First operation)
In the first operation, hydrogen gas is produced using the ammonia adsorbent 5a, and the ammonia adsorbent in the ammonia adsorber 5b is regenerated.
That is, the first operation includes an ammonia decomposition step, an ammonia adsorption step, a hydrogen recovery step, an ammonia adsorber regeneration step, and a heating step of the ammonia decomposition apparatus, which will be described later.

[Ammonia decomposition process]
The ammonia decomposition step is a step of circulating the ammonia from the ammonia supply device 2 to the ammonia decomposition device 3 and decomposing the ammonia to generate the decomposition gas containing hydrogen, nitrogen and unreacted ammonia.
The temperature inside the ammonia decomposition apparatus 3 is preferably 400 to 800 ° C. When the temperature is 400 ° C. or higher, the decomposition of ammonia is promoted, and the content of unreacted ammonia in the decomposed gas is reduced. Further, when the temperature is 800 ° C. or lower, deterioration of the ammonia decomposition catalyst is suppressed, and the amount of energy consumption is suppressed. From this point of view, the temperature inside the ammonia decomposition apparatus 3 is more preferably 430 to 650 ° C, still more preferably 450 to 550 ° C, and even more preferably 480 to 520 ° C.

The pressure in the ammonia decomposition apparatus 3 is preferably 0.0 to 1.0 MPaG (gauge pressure). When the pressure is 0.0 MPaG or more, leakage of the atmosphere into the device is prevented. When the pressure is 1.0 MPaG or less, the ammonia decomposition reaction is an equilibrium reaction in which the number of molecules increases, so that the content of unreacted ammonia in the decomposition gas can be reduced.
From this point of view, the pressure in the ammonia decomposition apparatus 3 is more preferably 0.2 to 0.8 MPaG, still more preferably 0.3 to 0.7 MPaG, still more preferably 0.45 to 0.55 MPaG.

[Ammonia adsorption process]
In the ammonia adsorption step, the decomposition gas flowing out from the ammonia decomposition device 3 is circulated to the decomposition gas cooling device 4a (heat exchanger 4 for cooling the decomposition gas) to be cooled by carrying out the ammonia decomposition step, and then cooled. This is a step of circulating unreacted ammonia from one of the plurality of ammonia adsorbers 5a and 5b (ammonia adsorber 5a) to adsorb and remove unreacted ammonia from the decomposed gas to obtain the gas after removing the ammonia.
The temperature in the ammonia adsorber 5a is preferably 10 to 100 ° C. When the temperature is 10 ° C. or higher, a gas cooling device becomes unnecessary, and energy consumption can be reduced. Further, when the temperature is 100 ° C. or lower, the amount of ammonia adsorbed increases.
From this point of view, the temperature inside the ammonia adsorber 5a is more preferably 15 to 80 ° C, still more preferably 20 to 60 ° C, still more preferably 25 to 50 ° C.

The pressure in the ammonia adsorber 5a is preferably 0.1 to 1.0 MPaG. When the pressure is 0.1 MPaG or more, the amount of ammonia adsorbed per unit amount of the ammonia adsorbent becomes large. Further, when the pressure is 1.0 MPaG or less, energy consumption for boosting the gas can be reduced.
From this point of view, the pressure in the ammonia adsorber 5a is more preferably 0.15 to 0.8 MPaG, still more preferably 0.2 to 0.6 MPaG, and even more preferably 0.25 to 0.5 MPaG.

Further, the pressure P1 of the ammonia decomposition device 3 and the pressure P2 in the ammonia adsorber 5a are adjusted.
P1 ≧ P2
May be. This eliminates the need to provide a pressurizing device between the ammonia decomposition device 3 and the ammonia adsorber 5a, and suppresses operating costs and equipment costs.
Further, from the viewpoint of recovering hydrogen in the downstream hydrogen recovery device 6 using the pressure of the ammonia adsorber 5a, the pressure in the ammonia adsorber 5a is more preferably 0.2 to 0.8 MPaG, and further. It is preferably 0.25 to 0.6 MPaG, and even more preferably 0.3 to 0.5 MPaG.

[Hydrogen recovery process]
In the hydrogen recovery step, the gas after removing ammonia flowing out from one of the plurality of ammonia adsorbers 5a and 5b (ammonia adsorber 5a) is circulated to the hydrogen recovery device 6, and hydrogen is discharged from the gas after removing ammonia. It is a process of separating and flowing out, and discharging the remaining off-gas.

The temperature inside the hydrogen recovery device 6 is preferably 10 to 60 ° C.
The pressure in the hydrogen recovery device 6 is preferably 0.1 to 1.0 MPaG.
Each of the pressure P1 of the ammonia decomposition device 3, the pressure P2 of the ammonia adsorber 5 (ammonia adsorber 5a), and the pressure P3 of the hydrogen recovery device 6 is
P1 ≧ P2 ≧ P3
May be satisfied. As a result, it is not necessary to provide a pressurizing device between the ammonia decomposition device 3 and the ammonia adsorber 5a, and between the ammonia adsorber 5a and the hydrogen recovery device 6, and the operating cost and the equipment cost are suppressed.

[Ammonia adsorber regeneration process]
In the ammonia adsorber regeneration step, the off-gas flowing out of the hydrogen recovery device 6 is collected from the off-gas heating device 4b (decomposition gas cooling heat exchanger 4) and the rest of the plurality of ammonia adsorbers 5a and 5b (for example, ammonia). When the adsorber 5a is in use, it is a step of distributing it to the ammonia adsorber 5b) to regenerate the ammonia adsorber (ammonia adsorber 5b). When three or more ammonia adsorbers 5 are present, this regeneration step can be applied to at least one of a group of devices that are not adsorbing ammonia.
As described above, in the ammonia-removed gas supplied to the hydrogen recovery device 6, ammonia is removed from the ammonia decomposition gas (hydrogen, nitrogen and unreacted ammonia) in the ammonia adsorbing device 5. Therefore, the ammonia content in the off-gas flowing out from the hydrogen recovery device 6 is small. Therefore, by heating the off-gas and then circulating it in the ammonia adsorber 5b, the ammonia adsorbed on the ammonia adsorbent can be satisfactorily desorbed and the ammonia adsorbent can be regenerated.
Further, while the ammonia adsorber 5b is being regenerated, the ammonia adsorber 5a can be used to adsorb and remove ammonia from the decomposition gas.

The temperature inside the ammonia adsorber 5b when desorbing ammonia is preferably 100 to 500 ° C. When the temperature is 100 ° C. or higher, the ammonia adsorbent can be sufficiently regenerated. Further, if the temperature is 500 ° C. or higher, there is a concern that the adsorbent may deteriorate. From this point of view, the temperature inside the ammonia adsorber 5b is more preferably 200 to 450 ° C, still more preferably 300 to 430 ° C, and even more preferably 380 to 420 ° C.

The pressure in the ammonia adsorber 5b is preferably 0.0 to 0.5 MPaG. When the pressure is 0.0 MPaG or more, evacuation is unnecessary and energy is not required. Further, when the pressure is 0.5 MPaG or less, ammonia can be sufficiently desorbed. From this point of view, the pressure in the ammonia adsorber 5b is more preferably 0.0 to 0.45 MPaG, still more preferably 0.0 to 0.4 MPaG, and even more preferably 0.0 to 0.3 MPaG.

[Heating process of ammonia decomposition device]
In the heating step of the ammonia decomposition device, heat energy is generated by burning the adsorbent regenerated gas flowing out from the ammonia adsorber 5b in the combustion reaction device 7, and this combustion gas is used in the combustion gas flow path 24. This is a step of heating the ammonia decomposition device 3 by distributing it to the heating device 8 via the above.
The adsorbent reclaimed gas flowing out of the ammonia adsorbent 5b contains the ammonia desorbed from the ammonia adsorbent 5b. It also contains hydrogen contained in the off-gas that is not recovered by the hydrogen recovery device 6. Therefore, a high-temperature combustion gas can be obtained by burning the adsorbent regenerated gas in the combustion reaction device 7. Further, by heating the ammonia decomposition device 3 with this high-temperature combustion gas, the ammonia decomposition device 3 can be sufficiently heated.

(Second operation)
After continuing the above-mentioned first operation, the following second operation is carried out.
In the second operation, the ammonia adsorption step is performed using a part or all of the ammonia adsorber regenerated in the first operation (ammonia adsorber 5b), and in the first operation, it is used in the ammonia adsorption step. The ammonia adsorber regeneration step is carried out for the ammonia adsorber (ammonia adsorber 5a) that has been used. The other steps, that is, the ammonia decomposition step, the hydrogen recovery step, and the heating step of the ammonia decomposition apparatus are the same as those in the first operation.
In this way, continuous operation can be performed by repeating the first operation and the second operation.

[Second Embodiment]
<Hydrogen production equipment>
FIG. 2 is a schematic diagram of the hydrogen production apparatus 30 according to the second embodiment, and FIG. 3 is a schematic diagram illustrating a first operation using the hydrogen production apparatus 30 of FIG.
The hydrogen production device 30 according to the present embodiment includes an ammonia supply device 31, an ammonia decomposition device 32, a decomposition gas cooling device 33a (heat exchanger for cooling decomposition gas 33), an ammonia adsorption device 34, a hydrogen recovery device 35, and heating. It has a device 38.
The ammonia adsorber 34 has a plurality of (two in this embodiment) ammonia adsorbers 34a and 34b arranged in parallel.
Details of these devices 31, 32, 33a (33), 34, 35, 38 are as described in the first embodiment.
As will be described later, in the present embodiment, the decomposition gas cooling device 33a is a heat exchanger 33 for cooling the decomposition gas, and also serves as an off-gas heating device 33b.

Further, the hydrogen production device 30 includes an ammonia flow path 41 connecting the ammonia supply device 31 and the ammonia decomposition device 32, a decomposition gas flow path 42 connecting the ammonia decomposition device 32 and the ammonia adsorption device 34, and an ammonia adsorption device 34. It has a gas flow path 43 after removing ammonia that connects to the hydrogen recovery device 35, and a hydrogen flow path 44 that allows hydrogen separated by the hydrogen recovery device 35 to flow out.
One end (upstream end) of the decomposition gas flow path 42 is connected to the ammonia decomposition device 32, the other end is branched to become branch flow paths 42a and 42b, and the branch flow path 42a is connected to the ammonia adsorbent 34a and branches. The flow path 42b is connected to the ammonia adsorber 34b. Each of the branch flow paths 42a and 42b has an on-off valve.
Further, in the gas flow path 43 after removing ammonia, one end (upstream end) is branched to become branch flow paths 43a and 43b, the branch flow path 43a is connected to the ammonia adsorber 34a, and the branch flow path 43b is an ammonia adsorber. It is connected to 34b. Further, the other end of the gas flow path 43 after removing ammonia merges and is connected to the hydrogen recovery device 35. Each of the branch flow paths 43a and 43b has an on-off valve.
The flow rate control valve V1 is provided in the ammonia flow path 41. Further, the hydrogen flow path 44 is provided with a pressure control valve V2.

Ammonia heating heat exchanger 51 and an ammonia auxiliary heating heat exchanger 52 are provided on the downstream side of the ammonia flow path 41 on the downstream side of the flow control valve V1 in order from the upstream side (ammonia supply device 31 side). There is.
Of the decomposition gas flow paths 42, on the upstream side of the branch paths 42a and 42b, the decomposition gas cooling device 33a (heat exchanger 33 for cooling the decomposition gas) and the ammonia are in this order from the upstream side (ammonia decomposition device 32 side). A heat exchanger 51 for heating and a heat exchanger 54 for water heating are provided.
That is, the ammonia flow path 41 and the decomposition gas flow path 42 intersect, and the ammonia heating heat exchanger 51 is provided at the intersection. Therefore, ammonia flows through one of the tube side and the shell side of the ammonia heating heat exchanger 51, and the decomposition gas flows through the other, so that heat can be exchanged between the ammonia and the decomposition gas.

Further, the hydrogen production device 30 is connected to the hydrogen recovery device 35 via the connection flow path 61 connected to the hydrogen recovery device 35 and the connection flow path 61, and the connection flow path 61 is connected from the hydrogen recovery device 35. It has an off-gas heating device 33b (heat exchanger 33 for cooling decomposed gas) that heats off-gas flowing out through it.
In the present embodiment, the decomposition gas cooling device 33a and the off-gas heating device 33b are the same heat exchanger (heat exchanger 33 for cooling the decomposition gas), and the decomposition gas flowing out from the ammonia decomposition device 32 and the hydrogen. It is said that heat can be exchanged with the off-gas flowing out from the recovery device 35.

Further, one end of the hydrogen production device 30 is connected to the off-gas heating device 33b (heat exchanger 33 for cooling the decomposed gas), and the other end is branched and connected to the plurality of ammonia adsorbers 34a and 34b. It has an off-gas flow path 62 in which off-gas is supplied to a used ammonia adsorber to regenerate the ammonia adsorber.
That is, one end (upstream end) of the off-gas flow path 62 is connected to the off-gas heating device 33b (decomposition gas cooling heat exchanger 33), and the other end branches to become branch flow paths 62a and 62b. The flow path 62a is connected to the upstream side of the branch flow path 43a of the gas flow path 43 after removing ammonia from the on-off valve, and the branch flow path 62b opens and closes of the branch flow path 43b of the gas flow path 43 after removing ammonia. It is connected to the upstream side of the valve. Each of these branch flow paths 43a and 43b has an on-off valve.

Further, the hydrogen production apparatus 30 is connected to a plurality of the ammonia adsorbers 34a and 34b, and adsorbs the adsorbent reclaimed gas flow path 63 through which the adsorbent regenerated gas flowing out from the used ammonia adsorber flows. A combustion reaction device 36 that is connected to the material reclaimed gas flow path 63 and burns the adsorbent reclaimed gas to flow out the combustion gas, and one end connected to the combustion reaction device 36 and the other end is the heating device 38. It has a combustion gas flow path 64 connected to the.
Specifically, the adsorbent regenerated gas flow path 63 has one end (upstream end) branched to form a branch flow path 63a63b, and the branch flow path 63a is one of the branch flow paths 42a of the decomposition gas flow path 42 described above. It is connected to the downstream side of the on-off valve, and the branch flow path 63b is connected to the downstream side of the on-off valve of the above-mentioned branch flow path 42b of the decomposition gas flow path 42. That is, the adsorbent regenerated gas flow path 63 is connected to the ammonia adsorbents 34a and 34b via the branch flow paths 42a and 42b of the decomposition gas flow path 42 described above. The other end of the adsorbent regenerated gas flow path 63 merges and is connected to the combustion reaction device 36. Each of these branch flow paths 63a and 63b has an on-off valve.

In the present embodiment, the oxygen supply device 37 is provided at a position downstream of the branch flow paths 63a and 63b in the adsorbent regenerated gas flow path 63.

Further, the hydrogen production apparatus 30 has a circulating gas flow path 71 having one end connected to the heating device 38 and the other end connected to the adsorbent reclaimed gas flow path 63.
The oxygen supply device 37 is connected to one or both of the adsorbent regenerated gas flow path 63 and the circulating gas flow path 71. In this embodiment, the oxygen supply device 37 is connected to the adsorbent reclaimed gas flow path 63.

The hydrogen production device 30 has a heated water supply device 80. The heated water supply device 80 includes a water flow path 81 that intersects the circulating gas flow path 71, a hot water heating heat exchanger 73 installed at an intersection between the circulating gas flow path 71 and the water flow path 81, and the heat exchanger 73 for heating the hot water. It has a shower head 82 provided at the downstream end of 81 of the water flow path. Therefore, the circulating gas flows through one of the tube side and the shell side of the hot water heating heat exchanger 73, and the hot water passes through the other, so that heat can be exchanged between the circulating gas and the hot water, and the water flow. The hot water flowing through the road 81 is heated to become heated water.
The internal fluid existing from the water heating heat exchanger 54 to the hot water heating heat exchanger 73 is referred to as "hot water", and the internal fluid downstream of the internal fluid is referred to as "heated water".

Further, the position upstream of the hot water heating heat exchanger 73 in the water flow path 81 is upstream of the branch flow paths 42a and 42b of the decomposition gas flow path 42 described above and heat exchange for ammonia heating. It intersects with a position downstream of the vessel 51 to form an intersection, and a water heating heat exchanger 54 is installed at the intersection. Decomposition gas flows through one of the tube side and the shell side of the water heating heat exchanger 54, and water passes through the other, so that heat can be exchanged between the decomposition gas and water.
A drain pot 74 for removing water in the circulating gas is provided downstream of the hot water heating heat exchanger 73 in the circulating gas flow path 71.

The circulating gas flow path 71 is an intersection where a first point located upstream of the hot water heating heat exchanger 73 and a second point located downstream of the drain pot 74 intersect. The portion of the circulating gas flow path 71 between the first point and the second point is an annular flow path 71a, and a heat exchanger 72 for circulating gas is installed at the intersection. Therefore, the combustion gas (circulating gas) that has flowed from the combustion gas flow path 64 into the circulating gas flow path 71 via the heating device 38 passes through either the tube side or the shell side of the heat exchanger 72 for circulating gas, and then passes through one of the tube side and the shell side. It is possible to flow through the annular flow path 71a of the circulating gas flow path 71, and then pass through the other of the tube side and the shell side of the heat exchanger 72 for circulating gas.
The above-mentioned heat exchanger 73 for heating hot water, a drain pot 74, and a circulation machine 75 are provided in the annular flow path 71a in this order from the upstream side.

Further, the gas waste flow path 76 branches from the position downstream of the drain pot 74 and upstream side of the circulation machine 75 in the circulation gas flow path 71. However, the gas waste flow path 76 may branch from any position in the circulating gas flow path 71.

One end and the other end of the bypass flow path 77 are connected to a portion in the middle of the combustion gas flow path 64 and a portion of the circulation gas flow path 71 upstream of the heat exchanger 72 for circulating gas, respectively. ing.
The bypass flow path 77 intersects with the above-mentioned ammonia flow path 41, and the above-mentioned ammonia auxiliary heating heat exchanger 52 is provided at the intersection. Therefore, ammonia flows through one of the tube side and the shell side of the ammonia auxiliary heating heat exchanger 52, and the combustion gas passes through the other, thereby heating the ammonia by heat exchange between the ammonia and the combustion gas. be able to.

In this embodiment, the decomposed gas flow path 42 and the ammonia-removed gas flow path 43 do not have a pressurizing device. This makes it possible to reduce equipment costs and operating costs.
However, a pressurizing device may be provided in at least one of the decomposition gas flow path 42 and the gas flow path 43 after removing ammonia. As a result, the pressure of the ammonia decomposition device 32 can be lowered to improve the ammonia decomposition efficiency, and the pressure of the gas after removing the ammonia flowing into the hydrogen recovery device 35 can be increased to improve the hydrogen recovery efficiency. When the pressurizing device is provided, it is preferable to provide it only in the gas flow path 43 after removing ammonia among the decomposition gas flow path 42 and the gas flow path 43 after removing ammonia.

(Combustion reactor)
The combustion reaction device 36 is not particularly limited as long as it can burn hydrogen and ammonia, but it is preferable that the combustion reaction device 36 accommodates a combustion catalyst from the viewpoint of efficient combustion.
Examples of the catalyst used in the combustion reactor include palladium, platinum and the like, but palladium is preferable from the viewpoint of cost.

(Oxygen supply device)
The oxygen-containing gas supplied from the oxygen supply device 37 is not particularly limited, and examples thereof include oxygen supplied from air, an oxygen cylinder, and the like, but air is preferable from the viewpoint of safety and economy.
The oxygen supply device 37 is not particularly limited as long as it can supply oxygen to the adsorbent reclaimed gas flow path 63, and examples thereof include various compressors.
(Circulator)
The circulation machine 75 is not particularly limited, and examples thereof include a blower, a fan, and various compressors.
(Heating water supply device)
As described above, the heated water supply device 80 includes the water flow path 81, the shower head 82 provided at the tip of the water flow path 81, the water heating heat exchanger 54 provided in the water flow path 81, and the hot water heating heat exchange. It has a vessel 73. With this device, heated water can be supplied to the ammonia supply device 31 to heat the ammonia inside.

<Hydrogen production method>
Next, an example of a hydrogen production method using the hydrogen production apparatus 30 described above will be described.
In the hydrogen production method according to the present embodiment, the first operation and the second operation, which will be described later, are repeated.

(First operation)
In the first operation, hydrogen gas is produced using the ammonia adsorbent 34a, and the ammonia adsorbent in the ammonia adsorber 34b is regenerated.
That is, the first operation includes an ammonia decomposition step, an ammonia adsorption step, a hydrogen recovery step, an ammonia adsorber regeneration step, a heating step of the ammonia decomposition device, a combustion gas circulation step, and a water heating step, which will be described later.

[Ammonia decomposition process]
The ammonia decomposition step is a step of circulating the ammonia from the ammonia supply device 31 to the ammonia decomposition device 32 and decomposing the ammonia to generate the decomposition gas containing hydrogen, nitrogen and unreacted ammonia.
That is, first, prior to the ammonia decomposition step, the heated water is supplied from the shower head 82 of the heated water supply device 80 to the ammonia supply device 31 as described in the water heating step described later. As a result, the liquid ammonia in the ammonia supply device 31 is vaporized and flows through the ammonia flow path 41.
The ammonia in the ammonia flow path 41 is heated by the ammonia heating heat exchanger 51 and the ammonia auxiliary heating heat exchanger 52 after the flow rate is adjusted by the flow control valve V1, and then flows to the ammonia decomposition device 32. In the ammonia decomposition device 32, ammonia is decomposed to generate the decomposition gas containing hydrogen, nitrogen and unreacted ammonia.
The temperature and pressure in the ammonia decomposition apparatus 32 are as described in the first embodiment.

[Ammonia adsorption process]
In the ammonia adsorption step, the decomposition gas flowing out from the ammonia decomposition device 32 due to the implementation of the ammonia decomposition step is collected by the decomposition gas cooling device 33a (heat exchanger 33 for cooling the decomposition gas) and the heat exchanger 51 for heating the ammonia. , And after cooling by passing through the heat exchanger 54 for water heating, it is passed through one of the plurality of ammonia adsorbers 34a and 34b (ammonia adsorber 34a) to adsorb and remove unreacted ammonia from the decomposition gas. This is a step of obtaining gas after removing the ammonia.
The temperature and pressure in the ammonia adsorber 34a are as described in the first embodiment described above.

[Hydrogen recovery process]
In the hydrogen recovery step, the gas after removing ammonia flowing out from one of the plurality of ammonia adsorbers 34a and 34b (ammonia adsorber 34a) is circulated to the hydrogen recovery device 35, and hydrogen is discharged from the gas after removing ammonia. It is a process of separating and flowing out, and discharging the remaining off-gas.
The temperature and pressure in the hydrogen recovery device 35 are as described in the first embodiment described above.

In the present embodiment, the hydrogen flow path 44 connected to the hydrogen recovery device 35 and flowing out the hydrogen separated by the hydrogen recovery device 35, and the pressure control valve V2 installed in the hydrogen flow path 44. , Have. Further, in the present embodiment, the flow path from the ammonia supply device 31 to the ammonia flow path 41, the ammonia decomposition device 32, the decomposition gas flow path 42, the ammonia adsorption device 34, and the gas flow path 43 after removing ammonia is provided. There are no heating devices other than heat exchangers, that is, energy supply type heaters. Therefore, by controlling the pressure control valve V2, each of the pressure P1 of the ammonia decomposition device 32, the pressure P2 of the ammonia adsorption device 34 (ammonia adsorber 34a), and the pressure P3 of the hydrogen recovery device 35 can be obtained.
P1 ≧ P2 ≧ P3
It is possible to control the pressure within a predetermined pressure range that satisfies the above relationship.

[Ammonia adsorber regeneration process]
In the ammonia adsorber regeneration step, the off-gas flowing out of the hydrogen recovery device 35 is circulated through the off-gas heating device 33b (decomposition gas cooling heat exchanger 33) to be heated, and then the plurality of ammonia adsorbers are used. This is a step of circulating the rest of 34a and 34b (for example, the ammonia adsorber 34b when the ammonia adsorber 34a is in use) to desorb and desorb ammonia to regenerate the ammonia adsorber (ammonia adsorber 34b).

As described above, in the ammonia-removed gas supplied to the hydrogen recovery device 35, ammonia is removed from the ammonia decomposition gas (hydrogen, nitrogen and unreacted ammonia) in the ammonia adsorbing device 34 upstream thereof. Therefore, the ammonia content in the off-gas flowing out from the hydrogen recovery device 35 is small. Therefore, by heating the off-gas and then circulating it in the ammonia adsorber 34b, the ammonia adsorbed on the ammonia adsorbent can be satisfactorily desorbed and regenerated.
Further, while the ammonia adsorber 34b is being regenerated, the ammonia adsorber 34a can be used to adsorb and remove ammonia from the decomposition gas.
The temperature and pressure in the ammonia adsorber 34b are as described in the first embodiment described above.

[Heating process of ammonia decomposition device]
In the heating step of the ammonia decomposition device 32, first, the adsorbent regenerated gas flowing out from the ammonia adsorbent 34b is mixed with the oxygen-containing gas from the oxygen supply device 37 and the circulating gas from the circulating gas flow path 71 described later. Use a mixed gas. Next, the mixed gas is supplied to the combustion reaction device 36 and burned to obtain a high-temperature combustion gas. Next, the combustion gas is circulated to the heating device 38 via the combustion gas flow path 64.
As described above, in the present embodiment, the mixed gas in which the adsorbent regenerated gas, the circulating gas described later, and the oxygen-containing gas are mixed is burned by the combustion reaction device 36. Therefore, by adjusting the mixing amount of the circulating gas and the oxygen-containing gas to adjust the composition of the mixed gas, the mixed gas can be efficiently burned. Further, by using a part or all of the circulating gas, the amount of gas that exchanges heat with the ammonia decomposition device 32 can be increased, thereby improving energy efficiency.
The temperature of the adsorbent regenerated gas supplied to the combustion reaction device 36, the temperature inside the combustion reaction device 36, and the pressure inside the combustion reaction device 36 are as described in the above-described first embodiment.

[Combustion gas circulation process]
In the combustion gas circulation step, the combustion gas after heating the ammonia decomposition device 32 is circulated as circulating gas to the heat exchanger 72 for circulating gas and the heat exchanger 73 for hot water heating to be cooled and then cooled. The water condensed by the above is removed by the drain pot 74, and then a part or all of the cooled circulating gas is circulated again to the heat exchanger 72 for circulating gas to heat it, and the adsorbent regenerated gas and the oxygen-containing gas are described above. This is a step of distributing the gas to the combustion reaction device 36 and burning the gas.
By cooling the circulating gas in this way, the volume of the circulating gas can be reduced, and thereby the circulation machine 75 can be miniaturized.
When a part of the circulating gas after heating the ammonia decomposition device 32 is circulated to the combustion reaction device 36 together with the adsorbent regenerated gas for combustion, the rest of the circulating gas is discarded. It may be discharged to the outside of the system via the flow path 76.
Here, the gas that flows through the circulating gas flow path after the combustion gas has passed through the ammonia decomposition device is called a circulating gas.

When the mixed gas is burned in the combustion reaction device 36, at least one of hydrogen and ammonia in the mixed gas reacts with oxygen to generate water. Therefore, in the present embodiment, after the water is removed by the drain pot 74 provided in the circulating gas flow path 71, the water is circulated to the combustion reaction device 36 together with the adsorbent regenerated gas for combustion.

[Water heating process]
The water heating step is a step of heating ammonia with heated water, and more specifically, after water is circulated to the water heating heat exchanger 54 and the hot water heating heat exchanger 73 to make heated water, This is a step of supplying heated water from the shower head 82 to the ammonia supply device 31 to vaporize the ammonia.
The temperature of the heated water flowing out from the shower head 82 is preferably 0 to 80 ° C, more preferably 10 to 60 ° C, still more preferably 20 to 50 ° C, still more preferably 30 to 45 ° C.

(Second operation)
After continuing the above-mentioned first operation, the following second operation is carried out.
In the second operation, the ammonia adsorption step is performed using the ammonia adsorber 34b regenerated in the first operation, and the ammonia adsorption step is performed using the ammonia adsorber 34a which is performing the ammonia adsorption step in the first operation. Carry out the vessel regeneration process. The other steps, that is, the ammonia decomposition step, the hydrogen recovery step, and the heating step of the ammonia decomposition apparatus are the same as those in the first operation.
In this way, continuous operation can be performed by repeating the first operation and the second operation.

[Third Embodiment]
<Hydrogen production equipment>
FIG. 4 is a schematic view of the hydrogen production apparatus 30A according to the third embodiment.
In the hydrogen production apparatus 30 of FIGS. 2 and 3, the hydrogen production apparatus 30A of FIG. 4 does not recycle the combustion gas, that is, the combustion gas that has passed through the heating device 38 that heats the ammonia decomposition apparatus 32 is burned again. It is modified so that it is discarded outside the hydrogen production device without being returned to the device 36, and a mixed gas of the adsorbent regenerated gas and the oxygen-containing gas is supplied to the combustion reaction device 36 for combustion.
That is, in the hydrogen production device 30A, in the hydrogen production device 30, the circulating gas flow path 71, the pipes and devices installed in the circulating gas flow path 71, and the oxygen supply device 37 are omitted, and the piping described later is described. And the equipment is installed.

(Devices not included in the hydrogen production device 30A)
That is, the hydrogen production device 30A of FIG. 4 has a circulating gas flow path 71, a heat exchanger 72 for circulating gas, a heat exchanger 73 for heating hot water, a drain pot 74, a circulation machine 75, and a gas waste flow path in the hydrogen production device 30. It does not have 76 and an oxygen supply device 37.

(Equipment added in hydrogen production equipment 30A)
As shown in FIG. 4, the hydrogen production apparatus 30A has a heat recovery flow path 71A having one end connected to the heating device 38 and the other end connected to the drain pot 74A. Further, a gas waste flow path 76A is connected to the drain pot 74A.
The heat recovery flow path 71A intersects with the oxygen supply flow path 37B, and an oxygen gas heating heat exchanger 72A is installed at the intersection. The gas in the heat recovery flow path 71A is passed through one of the tube side and the shell side of the oxygen gas heating heat exchanger 72A, and the gas in the oxygen supply flow path 37B is passed through the other. One end of the oxygen supply flow path 37B is connected to the oxygen supply device 37A, and the other end is connected to the downstream side of the adsorbent regenerated gas flow path 63 from the branch flow path 63a63b.
Further, the portion of the heat recovery flow path 71A on the downstream side of the oxygen gas heating heat exchanger 72A intersects with the portion of the water flow path 81 on the downstream side of the water heating heat exchanger 54. A heat exchanger 73A for heating hot water is installed at the intersection. The gas in the heat recovery flow path 71A is passed through one of the tube side and the shell side of the hot water heating heat exchanger 73A, and the hot water in the water flow path 81 is passed through the other. The downstream end of the water flow path 81 is connected to the shower head 82.
The internal fluid existing from the water heating heat exchanger 54 to the hot water heating heat exchanger 73A is referred to as "hot water", and the internal fluid downstream of the internal fluid is referred to as "heated water".
The configuration of the hydrogen production device 30A other than the above is the same as that of the hydrogen production device 30, and the same reference numerals mean the same devices or pipes.

<Hydrogen production method>
Next, an example of a hydrogen production method using the above-mentioned hydrogen production apparatus 30A will be described.
In the hydrogen production method according to the present embodiment, the first operation and the second operation, which will be described later, are repeated.

(First operation)
In the first operation, hydrogen gas is produced using the ammonia adsorbent 34a, and the ammonia adsorbent in the ammonia adsorber 34b is regenerated.
That is, the first operation includes an ammonia decomposition step, an ammonia adsorption step, a hydrogen recovery step, an ammonia adsorber regeneration step, a heating step of the ammonia decomposition device, a heat recovery step, and a water heating step, which will be described later.

[Ammonia decomposition process]
It is the same as the second embodiment.
[Ammonia adsorption process]
It is the same as the second embodiment.
[Hydrogen recovery process]
It is the same as the second embodiment.
[Ammonia adsorber regeneration process]
It is the same as the second embodiment.

[Heating process of ammonia decomposition device]
In the heating step of the ammonia decomposition apparatus 32, first, the adsorbent regenerated gas flowing out from the ammonia adsorbent 34b is mixed with the oxygen-containing gas from the oxygen supply apparatus 37A to obtain a mixed gas. Next, the mixed gas is supplied to the combustion reaction device 36 and burned to obtain a high-temperature combustion gas. Next, the combustion gas is passed through the combustion gas flow path 64 to the heating device 38 to heat the ammonia decomposition device 32.
As described above, in the present embodiment, the mixed gas in which the adsorbent regenerated gas and the oxygen-containing gas are mixed is burned by the combustion reaction device 36. Therefore, by adjusting the amount of the oxygen-containing gas to adjust the composition of the mixed gas, the mixed gas can be efficiently burned.
The temperature of the adsorbent regenerated gas supplied to the combustion reaction device 36, the temperature inside the combustion reaction device 36, and the pressure inside the combustion reaction device 36 are as described in the above-described first embodiment.

[Heat recovery process]
In the heat recovery step, the combustion gas after heating the ammonia decomposition device 32 is circulated through the oxygen gas heating heat exchanger 72A and the hot water heating heat exchanger 73A to be cooled, and then condensed by cooling. Is removed by the drain pot 74A, and then discharged to the outside of the system via the gas waste flow path 76A.

When the mixed gas is burned in the combustion reaction device 36, at least one of hydrogen and ammonia in the mixed gas reacts with oxygen to generate water. Therefore, in the present embodiment, the water is removed by the drain pot 74A provided in the heat recovery flow path 71A and then discharged to the outside of the system.

[Water heating process]
The water heating step is a step of heating ammonia with heated water, and more specifically, after water is circulated to the water heating heat exchanger 54 and the hot water heating heat exchanger 73A to make heated water, This is a step of supplying heated water from the shower head 82 to the ammonia supply device 31 to vaporize the ammonia.
The temperature of the heated water flowing out from the shower head 82 is preferably 0 to 80 ° C, more preferably 10 to 60 ° C, still more preferably 20 to 50 ° C, still more preferably 30 to 45 ° C.

(Second operation)
After continuing the above-mentioned first operation, the following second operation is carried out.
In the second operation, the ammonia adsorption step is performed using the ammonia adsorber 34b regenerated in the first operation, and the ammonia adsorption step is performed using the ammonia adsorber 34a which is performing the ammonia adsorption step in the first operation. Carry out the vessel regeneration process. The other steps are the same as in the first operation.
In this way, continuous operation can be performed by repeating the first operation and the second operation.

[Fourth Embodiment]
<Hydrogen production equipment>
FIG. 5 is a schematic view of the hydrogen production apparatus 30B according to the fourth embodiment.
In the hydrogen production apparatus 30B of FIG. 5 and FIG. 3, the hydrogen production apparatus 30 of FIGS. 2 and 3 is provided with an ammonia abatement facility 90 in the gas waste flow path 76.

That is, the gas waste flow path 76 includes a first gas waste flow path 91 whose one end is connected to the annular flow path 71a and an auxiliary ammonia adsorption device 92 connected to the other end of the first gas waste flow path 91. The ammonia abatement facility 90 is connected to the auxiliary ammonia adsorbing device 92 and includes a second gas disposal flow path 93 for passing the gas discharged from the auxiliary ammonia adsorbing device 92.

In the present embodiment, the auxiliary ammonia adsorber 92 has a plurality of (two) auxiliary ammonia adsorbers 92a and 92b arranged in parallel.
The upstream end of the first gas waste flow path 91 is connected to the annular flow path 71a, and the downstream end branches to form a plurality (two) first branch flow paths 91a and 91b, which are the plurality of auxiliary channels. It is connected to the ammonia adsorbers 92a and 92b.
The upstream end of the second gas waste flow path 93 is branched into a plurality (two) second branch flow paths 93a and 93b, which are connected to the plurality of auxiliary ammonia adsorbers 92a and 92b.

The ammonia abatement facility 90 is further connected to a regenerated gas supply device 94 that supplies regenerated gas to the plurality of auxiliary ammonia adsorbers 92a and 92b, one end of which is connected to the regenerated gas supply device 94, and a plurality of ends (2). The regenerated gas flow path 96 (96a, 96b) branched into the second branch flow path 93a, 93b and connected to the second branch flow path 93a, 93b, and the regenerated gas flow path 96 are provided in the middle of the regenerated gas flow path 96 to heat the regenerated gas. It has a regenerated gas heater 95 and the like.
Further, the ammonia abatement facility 90 has a desorption gas flow path 97 (97a, 97b) having one end branched into a plurality (two) and connected to the first branch flow paths 91a, 91b, and the desorption gas flow path. A waste gas combustion reactor 98, which is connected to the other end of 97 and burns the adsorbent desorbing gas discharged from each of the plurality of auxiliary ammonia adsorbents 92a and 92b to discharge the combustion gas, and the waste. It has a return flow path 100 for returning the combustion gas discharged from the gas combustion reactor 98 to the second gas waste flow path 93.
The return flow path 100 is provided with a waste gas cooler 99 for cooling the combustion gas flowing out of the waste gas combustion reactor.
Further, the ammonia abatement facility 90 has a bypass flow path 101 having one end connected to the first gas waste flow path 91 and the other end connected to the second gas waste flow path 93.

<Hydrogen production method>
In the present embodiment, in addition to being able to carry out the same hydrogen production method as in the second embodiment, the next ammonia detoxification step, the auxiliary ammonia adsorber regeneration step, and the bypass operation step are carried out. Can be done.

(Ammonia detoxification process)
The ammonia abatement step is a step of supplying the gas flowing through the gas waste flow path 76 to the ammonia abatement facility 90 to abatement the ammonia. In the present embodiment, there are cases where the auxiliary ammonia adsorber 92a is used to detoxify ammonia and cases where the auxiliary ammonia adsorber 92b is used to detoxify ammonia.
For example, the gas flowing through the gas waste flow path 76 is supplied to the auxiliary ammonia adsorbent 92a via the first gas waste flow path 91 and the first branch flow path 91a to detoxify the ammonia, and then the second branch. It may be discharged through the flow path 93a and the second gas disposal flow path 93.
Further, the gas flowing through the gas waste flow path 76 is supplied to the auxiliary ammonia adsorber 92b via the first gas waste flow path 91 and the first branch flow path 91b, and after detoxifying the ammonia, the second branch is performed. It may be discharged through the flow path 93b and the second gas waste flow path 93.

In the ammonia abatement step, the operating conditions (temperature, pressure, etc.) in the auxiliary ammonia adsorber 92a or 92b are the same as the operating conditions in the ammonia adsorbing step by the ammonia adsorbents 5a and 5b described above.

Normally, the ammonia concentration in the gas in the gas disposal flow path 76 is at a level where there is no environmental problem even if the gas is discarded as it is. Therefore, the ammonia detoxification step may be carried out as necessary at the time of unsteady time such as the operation start work or the operation stop work of the hydrogen production apparatus 30B. This makes it possible to reliably prevent the outflow of ammonia to the outside of the system.
The amount of ammonia in the gas discharged to the outside of the system via the second gas waste flow path 93 is preferably 25 volume ppm or less. Therefore, it is preferable to carry out the ammonia abatement step when the amount of ammonia in the gas in the first gas waste flow path 91 exceeds 25 volume ppm.

(Regeneration process of auxiliary ammonia adsorber)
The step of regenerating the auxiliary ammonia adsorber is a step of regenerating the auxiliary ammonia adsorbers 92a and 92b used in the above-mentioned ammonia abatement step.
For example, when the auxiliary ammonia adsorber 92a is regenerated, the oxygen-containing gas from the regenerated gas supply device 94 is heated by the regenerated gas heater 95, and then via the regenerated gas flow paths 96, 96a and the second branch flow path 93a. Is supplied to the auxiliary ammonia adsorber 92a to regenerate the auxiliary ammonia adsorber 92a. The gas discharged from the auxiliary ammonia adsorber 92a is supplied to the waste gas combustion reactor 98 via the first branch flow path 91a, the desorbable gas flow path 97a, 97, and the flammable gas in the gas is burned. The gas after combustion is cooled by the waste gas cooler 99, and then discharged through the return flow path 100 and the second gas waste flow path 93.
When the auxiliary ammonia adsorber 92b is regenerated, the oxygen-containing gas from the regenerated gas supply device 94 is heated by the regenerated gas heater 95, and then via the regenerated gas flow paths 96, 96b and the second branch flow path 93b. It is supplied to the auxiliary ammonia adsorber 92b to regenerate the auxiliary ammonia adsorber 92b. The gas discharged from the auxiliary ammonia adsorber 92b is supplied to the waste gas combustion reactor 98 via the first branch flow path 91b, the desorbable gas flow path 97b, 97, and the flammable gas in the gas is burned. The gas after combustion is cooled by the waste gas cooler 99, and then discharged through the return flow path 100 and the second gas waste flow path 93.

In the regeneration step of the auxiliary ammonia adsorber, the regeneration conditions (temperature, pressure, etc.) of the auxiliary ammonia adsorber 92a or 92b are the same as the operating conditions in the ammonia adsorber regeneration step of regenerating the ammonia adsorbents 5a and 5b described above. be.
The operating conditions (temperature, pressure, etc.) of the waste gas combustion reactor 98 are the same as the operating conditions of the combustion reactor 36 described above.

(Bypass operation process)
As described above, it is preferable to carry out the ammonia detoxification step as needed in the unsteady state, and it is preferable to carry out the bypass operation step in the steady state.
In the bypass operation step, the gas flowing through the gas waste flow path 76 is supplied to the second gas waste flow path 93 via the first gas waste flow path 91 and the bypass flow path 101, and is supplied to the second gas waste flow path 93. Gas is discharged from the road 93.
As a result, the load on the ammonia abatement equipment 90 is reduced.

[Fifth Embodiment]
<Hydrogen production equipment>
FIG. 6 is a schematic view of the hydrogen production apparatus 30C according to the fifth embodiment.
The hydrogen production apparatus 30C of FIG. 6 is the hydrogen production apparatus 30B of FIG. 5 in which the ammonia abatement equipment 90A is provided in place of the ammonia abatement equipment 90.
The ammonia abatement equipment 90A uses a combustion reactor 36 instead of the waste gas combustion reactor 98 in the ammonia abatement equipment 90.
That is, in the ammonia abatement equipment 90A, one end of the desorption gas pipe 97 is branched into a plurality of (two: 97a, 97b) and connected to the first branch flow paths 91a and 91b. Further, the other end of the desorbable gas pipe 97 is connected to a position in the adsorbent reclaimed gas flow path 63 between the connection position of the oxygen supply device 37 and the connection position of the combustion reaction device 36.
Further, the combustion gas flow path 64 and the second gas waste flow path 93 are connected via the waste gas flow path 104 provided with the waste gas cooler 103.

<Hydrogen production method>
In the present embodiment, in addition to being able to carry out the same hydrogen production method as in the second embodiment, the next ammonia detoxification step, the auxiliary ammonia adsorber regeneration step, and the bypass operation step are carried out. Can be done.

(Ammonia detoxification process)
It is the same as the fourth embodiment.

(Regeneration process of auxiliary ammonia adsorber)
The step of regenerating the auxiliary ammonia adsorber is a step of regenerating the auxiliary ammonia adsorbers 92a and 92b used in the above-mentioned ammonia abatement step.
When the auxiliary ammonia adsorber 92a is regenerated, the oxygen-containing gas from the regenerated gas supply device 94 is heated by the regenerated gas heater 95 and then assisted via the regenerated gas flow paths 96, 96a and the second branch flow path 93a. It is supplied to the ammonia adsorber 92a to regenerate the auxiliary ammonia adsorber 92a. The gas discharged from the auxiliary ammonia adsorber 92a is supplied to the combustion reaction device 36 via the first branch flow path 91a, the desorption gas pipes 97a and 97, and the adsorbent reclaimed gas flow path 63, and is a combustible gas in the gas. Is burned. A part of the gas discharged from the combustion reaction device 36 is cooled by the waste gas cooler 103 and then discharged through the second gas waste flow path 93.
When the auxiliary ammonia adsorber 92b is regenerated, the oxygen-containing gas from the regenerated gas supply device 94 is heated by the regenerated gas heater 95, and then via the regenerated gas flow paths 96, 96b and the second branch flow path 93b. It is supplied to the auxiliary ammonia adsorber 92b to regenerate the auxiliary ammonia adsorber 92b. The gas discharged from the auxiliary ammonia adsorber 92b is supplied to the combustion reaction device 36 via the first branch flow path 91b, the desorption gas pipes 97b and 97, and the adsorbent reclaimed gas flow path 63, and is a flammable gas in the gas. Is burned. A part of the gas discharged from the combustion reaction device 36 is cooled by the waste gas cooler 103 and then discharged through the second gas waste flow path 93.
However, all of the gas discharged from the combustion reaction device 36 may be supplied to the heating device 38 via the combustion gas flow path 64. In that case, the waste gas flow path 104 provided with the waste gas cooler 103 may be omitted.

(Bypass operation process)
It is the same as the fourth embodiment.

[Sixth Embodiment]
<Hydrogen production equipment>
FIG. 7 is a schematic view of the hydrogen production apparatus 30D according to the sixth embodiment.
The hydrogen production apparatus 30D of FIG. 7 is the hydrogen production apparatus 30A of FIG. 4 provided with an ammonia abatement facility 90B.
The ammonia abatement equipment 90B is the same as the ammonia abatement equipment 90 in the fourth embodiment.

<Hydrogen production method>
In the present embodiment, the same hydrogen production method as in the third embodiment can be carried out.
Further, in the present embodiment, the ammonia detoxification step, the regeneration step of the auxiliary ammonia adsorber, and the bypass operation step can be carried out. In addition, these steps are the same as the 4th Embodiment.

[7th Embodiment]
<Hydrogen production equipment>
FIG. 8 is a schematic view of the hydrogen production apparatus 30E according to the seventh embodiment.
The hydrogen production apparatus 30E of FIG. 8 is the hydrogen production apparatus 30A of FIG. 4 provided with an ammonia abatement facility 90C.
The ammonia abatement equipment 90C is the same as the ammonia abatement equipment 90A in the fifth embodiment.

<Hydrogen production method>
In the present embodiment, the same hydrogen production method as in the third embodiment can be carried out.
Further, in the present embodiment, the ammonia detoxification step, the regeneration step of the auxiliary ammonia adsorber, and the bypass operation step can be carried out. In addition, these steps are the same as the 5th Embodiment.

1 Hydrogen production device 2 Ammonia supply device 3 Ammonia decomposition device 4 Decomposition gas cooling heat exchanger 4a Decomposition gas cooling device 4b Off-gas heating device 5 Ammonia adsorption device 5a 5b Ammonia adsorption device 6 Hydrogen recovery device 7 Burning reaction device 8 Heating equipment 11 Ammonia flow path 12 Decomposition gas flow path 14 Gas flow path after removing ammonia 15 Hydrogen flow path 21 Connection flow path 22 Off gas flow path 23 Adsorbent regeneration gas flow path 24 Combustion gas flow path 30 Hydrogen production device 31 Hydrogen supply device 32 Ammonia Decomposition device 33 Decomposition gas cooling heat exchanger 33a Decomposition gas cooling device 33b Off-gas heating device 34 Ammonia adsorption device 34a, 34b Ammonia adsorption device 35 Hydrogen recovery device 36 Burning reaction device 37 Oxygen supply device 38 Heating device 41 Ammonia flow path 42 Decomposition Gas flow path 43 Gas flow path after removing ammonia 44 Hydrogen flow path 51 Heat exchanger for heating ammonia 52 Heat exchanger for auxiliary heating of ammonia 54 Heat exchanger for water heating 61 Connection flow path 62 Off gas flow path 63 Adsorbent regenerated gas flow Road 64 Combustion gas flow path 71 Circulating gas flow path 71a Circular flow path 72 Heat exchanger for circulating gas 73 Heat exchanger for hot water heating 74 Drain pot 75 Circulator 76 Gas waste flow path 77 Bypass flow path 80 Heating water supply device 81 Water flow path 82 Shower head V1 Flow control valve V2 Pressure control valve 30A Hydrogen production device 37A Oxygen supply device 37B Oxygen supply flow path 71A Heat recovery flow path 72A Oxygen gas heating heat exchanger 73A Hot water heating heat exchanger 74A Drain pot 76A Gas disposal channel

Claims (20)

Ammonia supply device and
An ammonia decomposition device connected to the ammonia supply device, which decomposes ammonia to generate a decomposition gas containing hydrogen, nitrogen, and unreacted ammonia.
A decomposition gas cooling device connected to the ammonia decomposition device and cooling the decomposition gas, and a decomposition gas cooling device.
An ammonia adsorption device connected to the decomposition gas cooling device, which adsorbs and removes unreacted ammonia from the decomposition gas and discharges the gas after removing the ammonia.
A hydrogen recovery device that is connected to the ammonia adsorption device, separates hydrogen from the gas after removing the ammonia and flows out, and discharges the remaining off-gas.
A heating device that heats the ammonia decomposition device, and
Have and
The ammonia adsorber has a plurality of ammonia adsorbers arranged in parallel, and the decomposition gas from the decomposition gas cooling device can be supplied to any part of the plurality of ammonia adsorbers. It is a hydrogen production device that is
An off-gas heating device that is connected to the hydrogen recovery device and heats the off-gas,
An off-gas flow path in which one end is connected to the off-gas heating device and the other end is connected to the plurality of ammonia adsorbers, and the off-gas is supplied to a used ammonia adsorber to regenerate the ammonia adsorber.
An adsorbent reclaimed gas flow path that is connected to the plurality of the ammonia adsorbents and circulates the adsorbent reclaimed gas flowing out of the used ammonia adsorber.
A combustion reaction device that is connected to the adsorbent reclaimed gas flow path and burns the adsorbent reclaimed gas to discharge the combustion gas.
A combustion gas flow path having one end connected to the combustion reactor and the other end connected to the heating device.
Hydrogen production equipment with. The decomposition gas cooling device and the off-gas heating device are the same heat exchangers, and heat exchange is possible between the decomposition gas flowing out of the ammonia decomposition device and the off-gas flowing out of the hydrogen recovery device. The hydrogen production apparatus according to claim 1. The hydrogen production apparatus according to claim 1 or 2, wherein one end is connected to the heating device and the other end is connected to the adsorbent reclaimed gas flow path. The hydrogen production apparatus according to claim 3, wherein an oxygen supply device is connected to one or both of the adsorbent regenerated gas flow path and the circulating gas flow path. A water flow path that intersects the circulating gas flow path and
A heat exchanger for heating hot water installed at an intersection of the circulating gas flow path and the water flow path,
The hydrogen according to claim 3 or 4, which has a heated water supply device provided at a downstream end of the water flow path, and heats the ammonia supply device using the heated water flowing out of the heated water supply device. Manufacturing equipment. The hydrogen production according to claim 5, further comprising a drain pot for removing water in the circulating gas flowing through the circulating gas flow path downstream of the hot water heating heat exchanger in the circulating gas flow path. Device. The first point of the circulating gas flow path located upstream of the hot water heating heat exchanger and the second point located downstream of the drain pot intersect to form an intersection, and the circulating gas is formed. The portion of the flow path between the first point and the second point is an annular flow path.
The hydrogen production apparatus according to claim 6, wherein a heat exchanger for circulating gas is installed at the intersection. The hydrogen production apparatus according to claim 6 or 7, further comprising a circulating gas circulator downstream of the drain pot in the circulating gas flow path. The hydrogen production apparatus according to claim 7 , wherein a gas waste flow path for discharging a part or all of the circulating gas is connected in the middle of the annular flow path. The gas waste flow path
A first gas waste flow path whose one end is connected to the annular flow path,
Auxiliary ammonia adsorption device connected to the other end of the first gas waste flow path,
A second gas disposal flow path connected to the auxiliary ammonia adsorbing device and flowing the gas discharged from the auxiliary ammonia adsorbing device, and a second gas disposal flow path.
9. The hydrogen production apparatus according to claim 9, further comprising an ammonia abatement facility. The auxiliary ammonia adsorber has a plurality of auxiliary ammonia adsorbers arranged in parallel.
The first gas waste flow path has an upstream end connected to the annular flow path, and the downstream end branches to form a first branch flow path, which is connected to the plurality of auxiliary ammonia adsorbers.
The upstream end of the second gas waste flow path branches into a second branch flow path and is connected to the plurality of auxiliary ammonia adsorbers.
The ammonia abatement equipment is further enhanced.
A regenerated gas supply device that supplies regenerated gas to the plurality of auxiliary ammonia adsorbers,
A regenerated gas flow path, one end of which is connected to the regenerated gas supply device and the other end of which is branched and connected to the second branch flow path.
A regenerated gas heater provided in the middle of the regenerated gas flow path to heat the regenerated gas,
Desorption gas flow path, one end of which is branched and connected to the first branch flow path,
A waste gas combustion reactor connected to the other end of the desorption gas flow path and burning the adsorbent desorption gas discharged from each of the plurality of auxiliary ammonia adsorbents to discharge the combustion gas, and the waste gas. A return flow path for returning the combustion gas discharged from the gas combustion reactor to the second gas waste flow path,
The hydrogen production apparatus according to claim 10, which is an ammonia abatement facility comprising the above. The hydrogen production apparatus according to claim 11, wherein the waste gas combustion reactor is the combustion reactor. The hydrogen production apparatus according to claim 11 or 12, further comprising a waste gas cooler provided in the return flow path and for cooling the combustion gas flowing out of the waste gas combustion reactor. A hydrogen flow path connected to the hydrogen recovery device and flowing out hydrogen separated by the hydrogen recovery device,
The pressure control valve installed in the hydrogen flow path and
The hydrogen production apparatus according to any one of claims 1 to 13. An ammonia flow path connecting the ammonia supply device and the ammonia decomposition device,
The flow control valve installed in the ammonia flow path and
The hydrogen production apparatus according to any one of claims 1 to 14. Ammonia heating heat exchanger installed in the ammonia flow path,
It has a decomposition gas flow path that connects the ammonia decomposition device and the ammonia adsorption device.
The middle of the decomposition gas flow path is distributed to the heat exchanger for heating ammonia.
The hydrogen production apparatus according to claim 15, wherein the decomposed gas cooling device is installed on the upstream side of the decomposition gas flow path from the installation position of the ammonia heating heat exchanger. A decomposition gas flow path connecting the ammonia decomposition device and the plurality of ammonia adsorbents,
A gas flow path after removing ammonia connecting the plurality of ammonia adsorbers and the hydrogen recovery device,
Have and
The decomposition gas cooling device is installed in the middle of the decomposition gas flow path, and the decomposition gas cooling device is installed.
The hydrogen production apparatus according to any one of claims 1 to 16, wherein the decomposed gas flow path and the gas flow path after removing ammonia do not have a pressurizing device. The hydrogen production method using the hydrogen production apparatus according to any one of claims 1 to 17.
Ammonia decomposition step of circulating the ammonia from the ammonia supply device to the ammonia decomposition device and decomposing the ammonia to generate the decomposition gas containing hydrogen, nitrogen and unreacted ammonia.
The decomposition gas flowing out of the ammonia decomposition device is circulated to the decomposition gas cooling device to be cooled, and then circulated to a part of the plurality of ammonia adsorbers to adsorb and remove unreacted ammonia from the decomposition gas. Ammonia adsorption step to obtain gas after removing ammonia,
The gas after removing ammonia flowing out from the part of the plurality of ammonia adsorbers is circulated to the hydrogen recovery device to separate hydrogen from the gas after removing ammonia and flow out, and the remaining off-gas is discharged. Hydrogen recovery process,
An ammonia adsorber regeneration step in which the off-gas flowing out of the hydrogen recovery device is circulated through the off-gas heating device and a part or all of the rest of the plurality of ammonia adsorbers to regenerate the ammonia adsorber, and
The heating step of the ammonia decomposition device, in which the regenerated gas of the adsorbent flowing out of the ammonia adsorber is circulated to the combustion reaction device, the combustion gas flow path, and the heating device to heat the ammonia decomposition device.
A hydrogen production method. A hydrogen flow path connected to the hydrogen recovery device and flowing out hydrogen separated by the hydrogen recovery device,
The pressure control valve installed in the hydrogen flow path and
Have and
By controlling the pressure control valve, each of the pressure P1 of the ammonia decomposition device, the pressure P2 of the ammonia adsorption device, and the pressure P3 of the hydrogen recovery device can be changed.
P1 ≧ P2 ≧ P3
The hydrogen production method according to claim 18, wherein the hydrogen production method is controlled to a predetermined pressure range satisfying the above relationship. The hydrogen production apparatus is the hydrogen production apparatus according to any one of claims 10 to 13.
The hydrogen production method according to 18 or 19, further comprising an ammonia abatement step of supplying a gas flowing through the gas disposal flow path to the ammonia abatement facility to attenuate ammonia.

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