Hydrogen supply system and control device

Abstract

To provide a hydrogen supply system capable of improving system efficiency as a hydrogen supply system while suppressing deterioration of a dehydrogenation catalyst of a dehydrogenation reaction part.SOLUTION: In a hydrogen supply system 100, a hydrogen supply part 40 supplies to a dehydrogenation reaction part 3, at least one of hydrogen-containing gas between the dehydrogenation reaction part 3 and a gas-liquid separation part 6 for separating a dehydrogenation product from hydrogen-containing gas, and hydrogen-containing gas separated by the gas-liquid separation part 6 for separating a dehydrogenation product from hydrogen-containing gas. Due to that the hydrogen supply part 40 supplies hydrogen-containing gas at an upstream side of a hydrogen purification part 8 to the dehydrogenation reaction part 3, it is unnecessary to take out deterioration suppressing hydrogen of a dehydrogenation catalyst of the dehydrogenation reaction part 3 from the hydrogen purification part 8 so as to reduce energy to be charged into the hydrogen purification part 8.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a hydrogen supply system that supplies hydrogen. [Background technology]

[0002] Known conventional hydrogen supply systems include, for example, the one disclosed in Patent Document 1. The hydrogen supply system of Patent Document 1 includes a tank for storing a hydride of an aromatic hydrocarbon as a raw material, a dehydrogenation reaction section for obtaining hydrogen by dehydrogenating the raw material supplied from the tank, a gas-liquid separation section for separating the hydrogen obtained in the dehydrogenation reaction section into gas and liquid, and a hydrogen purification section for purifying the hydrogen obtained by gas-liquid separation. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2006-232607 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the hydrogen supply system as described above, when the generation of hydrogen-containing gas in the dehydrogenation reaction section is stopped, the supply of raw material may be stopped and an inert gas such as nitrogen may be supplied to the dehydrogenation reaction section. This purges the raw material remaining in the dehydrogenation reaction section. However, in this method, the dehydrogenation reaction section is at a high temperature and hydrogen is not present, so the dehydrogenation catalyst may deteriorate due to the generation of coke or the like. On the other hand, when hydrogen is taken out from the hydrogen purification device and supplied to the dehydrogenation reaction section, the hydrogen production device requires input energy for hydrogen that is not used as a product. Therefore, there has been a demand for improving the system efficiency as a hydrogen supply system while suppressing the deterioration of the dehydrogenation catalyst in the dehydrogenation reaction section.

[0005] The present invention has been made to solve the above-mentioned problems, and aims to provide a hydrogen supply system that can improve the system efficiency as a hydrogen supply system while suppressing deterioration of the dehydrogenation catalyst in the dehydrogenation reaction section. [Means for solving the problem]

[0006] In order to solve the above problems, the hydrogen supply system of the present invention is a hydrogen supply system that supplies hydrogen, and is equipped with a dehydrogenation reaction unit that obtains a hydrogen-containing gas by dehydrogenating a raw material containing a hydride, and a control unit that controls the hydrogen supply system, and when the control unit stops generating hydrogen-containing gas in the dehydrogenation reaction unit, the control unit causes the hydrogen supply unit to supply hydrogen to the dehydrogenation reaction unit, and the hydrogen supply unit supplies at least one of the hydrogen-containing gas between the dehydrogenation reaction unit and a gas-liquid separation unit that separates a dehydrogenation product from the hydrogen-containing gas, and the hydrogen-containing gas separated in the gas-liquid separation unit that separates the dehydrogenation product from the hydrogen-containing gas, to the dehydrogenation reaction unit.

[0007] In the hydrogen supply system, the dehydrogenation reaction section obtains hydrogen-containing gas by dehydrogenating a raw material containing a hydride. The dehydrogenation reaction section performs a dehydrogenation reaction in a state where the dehydrogenation catalyst is heated. Here, when the generation of hydrogen-containing gas in the dehydrogenation reaction section is stopped, the control section supplies hydrogen to the dehydrogenation reaction section. As a result, even when the dehydrogenation reaction section is stopped, hydrogen is present in the dehydrogenation reaction section. Therefore, it is possible to prevent the dehydrogenation reaction section from being in a high temperature state where no hydrogen is present, which causes coke to be deposited on the dehydrogenation catalyst. Furthermore, the hydrogen supply section supplies at least one of the hydrogen-containing gas between the dehydrogenation reaction section and the gas-liquid separation section that separates the dehydrogenation product from the hydrogen-containing gas, and the hydrogen-containing gas separated in the gas-liquid separation section that separates the dehydrogenation product from the hydrogen-containing gas, to the dehydrogenation reaction section. In this way, the hydrogen supply section supplies the hydrogen-containing gas upstream of the hydrogen purification section to the dehydrogenation reaction section. Therefore, it is not necessary to take out hydrogen for suppressing deterioration of the dehydrogenation catalyst in the dehydrogenation reaction section from the hydrogen purification section, so that the energy input to the hydrogen purification section can be reduced. As a result, the system efficiency as a hydrogen supply system can be improved while suppressing deterioration of the dehydrogenation catalyst in the dehydrogenation reaction section.

[0008] The hydrogen supply unit may supply hydrogen from an external source. In this case, the hydrogen supply unit can supply hydrogen without worrying about the remaining amount of hydrogen present in the system. Effect of the Invention

[0009] According to the present invention, it is possible to provide a hydrogen supply system that can improve the system efficiency as a hydrogen supply system while suppressing deterioration of the dehydrogenation catalyst in the dehydrogenation reaction section. [Brief description of the drawings]

[0010] [Figure 1] 1 is a block diagram showing a configuration of a hydrogen supply system according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the hydrogen supply system according to the present invention will now be described in detail with reference to the drawings. In the following description, the same or corresponding parts are designated by the same reference numerals, and duplicated description will be omitted.

[0012] FIG. 1 is a block diagram showing the configuration of a hydrogen supply system according to an embodiment of the present invention. The hydrogen supply system 100 uses an organic compound (liquid at room temperature) as a raw material. In the process of hydrogen purification, the raw organic compound (liquid at room temperature) is dehydrogenated and a dehydrogenation product (organic compound (liquid at room temperature)) is removed. An example of the organic compound as the raw material is organic hydride. A suitable example of the organic hydride is a hydride obtained by reacting hydrogen, which is produced in large quantities in oil refineries, with aromatic hydrocarbons. In addition, the organic hydride is not limited to aromatic hydrogenated compounds, and there is also a system of 2-propanol (which produces hydrogen and acetone). The organic hydride can be transported to the hydrogen supply system 100 as a liquid fuel by a tanker truck or the like, similar to gasoline. In this embodiment, methylcyclohexane (hereinafter referred to as MCH) is used as the organic hydride. In addition, aromatic hydrocarbon hydrides such as cyclohexane, dimethylcyclohexane, ethylcyclohexane, decalin, methyldecalin, dimethyldecalin, and ethyldecalin can be used as organic hydrides (aromatic compounds are particularly suitable examples with high hydrogen content). The hydrogen supply system 100 can supply hydrogen to fuel cell vehicles (FCVs) and hydrogen engine vehicles. It is also applicable to the production of hydrogen from liquid hydrocarbon raw materials such as natural gas containing methane as the main component, LPG containing propane as the main component, or gasoline, naphtha, kerosene, and diesel.

[0013] As shown in FIG. 1, the hydrogen supply system 100 according to the present embodiment includes a compression section 1, a heat exchange section 2, a dehydrogenation reaction section 3, a heating section 4, a gas-liquid separation section 6, a compression section 7, and a hydrogen purification section 8. Among these, the compression section 1, the heat exchange section 2, and the dehydrogenation reaction section 3 belong to a hydrogen production section 10 that produces a hydrogen-containing gas. The gas-liquid separation section 6, the compression section 7, and the hydrogen purification section 8 belong to a hydrogen purity adjustment section 11 that increases the purity of hydrogen. The hydrogen supply system 100 also includes lines L1 to L12. In this embodiment, MCH is used as a raw material, and a dehydrogenation product removed in the process of hydrogen purification is toluene. In reality, not only toluene but also unreacted MCH and a small amount of by-products and impurities are present, but in this embodiment, they are mixed with toluene and behave the same as toluene. Therefore, in the following description, what is referred to as "toluene" includes unreacted MCH and by-products.

[0014] The lines L1 to L12 are flow paths through which MCH, toluene, hydrogen-containing gas, off-gas, high-purity hydrogen, or a heating medium passes. The line L1 is a line for pumping MCH from an MCH tank (not shown) to the compression unit 1, and connects the compression unit 1 to the MCH tank. The line L2 connects the compression unit 1 to the dehydrogenation reaction unit 3. The line L3 connects the dehydrogenation reaction unit 3 to the gas-liquid separation unit 6. The line L4 connects the gas-liquid separation unit 6 to a toluene tank (not shown). The line L5 connects the gas-liquid separation unit 6 to the compression unit 7. The line L6 connects the compression unit 7 to the hydrogen purification unit 8. The line L7 connects the hydrogen purification unit 8 to a supply destination of the off-gas. The line L8 connects the hydrogen purification unit 8 to a supply device for purified gas (not shown). The lines L11 and L12 connect the heating unit 4 to the dehydrogenation reaction unit 3. The lines L11 and L12 allow the heat transfer medium to flow.

[0015] The compression unit 1 supplies the raw material MCH to the dehydrogenation reaction unit 3. Note that MCH transported from outside by a tank truck or the like is stored in an MCH tank. The MCH stored in the MCH tank is supplied by the compression unit 1 to the dehydrogenation reaction unit 3 via lines L1 and L2.

[0016] The heat exchanger 2 exchanges heat between the MCH flowing through the line L2 and the hydrogen-containing gas flowing through the line L3. The hydrogen-containing gas coming out of the dehydrogenation reaction section 3 has a higher temperature than the MCH. Therefore, in the heat exchanger 2, the MCH is heated by the heat of the hydrogen-containing gas. As a result, the MCH is supplied to the dehydrogenation reaction section 3 in a state where its temperature has increased. The MCH is supplied to the dehydrogenation reaction section 3 together with the off-gas supplied from the hydrogen purification section 8 via the line L7.

[0017] The dehydrogenation reaction section 3 is a device that obtains hydrogen by dehydrogenating MCH. That is, the dehydrogenation reaction section 3 is a device that extracts hydrogen from MCH by a dehydrogenation reaction using a dehydrogenation catalyst. The dehydrogenation catalyst is not particularly limited, but is selected from, for example, a platinum catalyst, a palladium catalyst, and a nickel catalyst. These catalysts may be supported on a carrier such as alumina, silica, and titania. The reaction of organic hydrides is a reversible reaction, and the direction of the reaction changes depending on the reaction conditions (temperature, pressure) (subject to the constraints of chemical equilibrium). On the other hand, the dehydrogenation reaction is an endothermic reaction that always increases the number of molecules. Therefore, high temperature and low pressure conditions are advantageous. Since the dehydrogenation reaction is an endothermic reaction, heat is supplied to the dehydrogenation reaction section 3 from the heating section 4 via a heat medium circulating through lines L11 and L12. The dehydrogenation reaction section 3 has a mechanism that allows heat exchange between the MCH flowing through the dehydrogenation catalyst and the heat medium from the heating section 4. The hydrogen-containing gas extracted in the dehydrogenation reaction section 3 is supplied to the gas-liquid separation section 6 via a line L3. The hydrogen-containing gas in the line L3 is supplied to the gas-liquid separation section 6 in a state where it contains toluene, which is a liquid, as a mixture.

[0018] The heating section 4 heats the heat medium and supplies the heat medium to the dehydrogenation reaction section 3 via a line L11. The heated heat medium is returned to the heating section 4 via a line L12. The heat medium is not particularly limited, and oil or the like may be used. The heating section 4 may be any type that can heat the dehydrogenation reaction section 3. For example, the heating section 4 may directly heat the dehydrogenation reaction section 3, or may heat the MCH supplied to the dehydrogenation reaction section 3 by heating the line L2. The heating section 4 may heat both the dehydrogenation reaction section 3 and the MCH supplied to the dehydrogenation reaction section 3. For example, a burner or an engine may be used as the heating section 4.

[0019] The gas-liquid separation unit 6 is a device that separates toluene from the hydrogen-containing gas. The gas-liquid separation unit 6 supplies the hydrogen-containing gas containing toluene as a mixture, and separates the gas and liquid into hydrogen, which is a gas, and toluene, which is a liquid. The hydrogen-containing gas supplied to the gas-liquid separation unit 6 is cooled by the heat exchange unit 2. The gas-liquid separation unit 6 may be cooled by a cooling medium from a cold heat source. In this case, the gas-liquid separation unit 6 has a mechanism capable of exchanging heat between the hydrogen-containing gas in the gas-liquid separation unit 6 and the cooling medium from the cold heat source. The toluene separated by the gas-liquid separation unit 6 is supplied to a toluene tank (not shown) via a line L4. The hydrogen-containing gas separated by the gas-liquid separation unit 6 is supplied to the hydrogen purification unit 8 via lines L5 and L6 by the pressure of the compression unit 7. When the hydrogen-containing gas is cooled, a part of the gas (toluene) is liquefied, and the gas-liquid separation unit 6 can separate the toluene from the non-liquefied gas (hydrogen). The lower the gas temperature, the more efficient the separation becomes, and increasing the pressure further promotes the liquefaction of toluene.

[0020] The hydrogen purification unit 8 removes the dehydrogenation product (toluene in this embodiment) from the hydrogen-containing gas obtained in the dehydrogenation reaction unit 3 and separated into gas and liquid in the gas-liquid separation unit 6. In this way, the hydrogen purification unit 8 purifies the hydrogen-containing gas to obtain high-purity hydrogen (purified gas). The obtained purified gas is supplied to line L8. The off-gas generated in the hydrogen purification unit 8 is supplied to the dehydrogenation reaction unit 3 via line L7.

[0021] The hydrogen purification unit 8 varies depending on the hydrogen purification method employed, but specifically, when membrane separation is used as the hydrogen purification method, it is a hydrogen separation device equipped with a hydrogen separation membrane, and when the PSA (pressure swing adsorption) method or the TSA (temperature swing adsorption) method is used, it is an adsorption removal device equipped with multiple adsorption towers that store adsorbents that adsorb impurities.

[0022] A case where the hydrogen purification unit 8 uses membrane separation will be described. In this method, a hydrogen-containing gas pressurized to a predetermined pressure by a compression unit (not shown) is made to pass through a membrane heated to a predetermined temperature, thereby removing dehydrogenation products and obtaining high-purity hydrogen gas (purified gas). The pressure of the permeated gas that has permeated the membrane is reduced compared to the pressure before permeating the membrane. On the other hand, the pressure of the non-permeated gas that has not permeated the membrane is approximately the same as the predetermined pressure before permeating the membrane. At this time, the non-permeated gas that has not permeated the membrane corresponds to the off-gas of the hydrogen purification unit 8.

[0023] There are no particular limitations on the type of membrane used in hydrogen purification unit 8, and it is possible to use porous membranes (those that separate by molecular flow, those that separate by surface diffusion flow, those that separate by capillary condensation, those that separate by molecular sieving, etc.) or non-porous membranes. As the membrane used in hydrogen purification unit 8, for example, metal membranes (PbAg-based, PdCu-based, Nb-based, etc.), zeolite membranes, inorganic membranes (silica membranes, carbon membranes, etc.), and polymer membranes (polyimide membranes, etc.) can be used.

[0024] A case where the PSA method is adopted as a removal method of the hydrogen purification unit 8 will be described. The adsorbent used in the PSA method has the property of adsorbing toluene contained in the hydrogen-containing gas under high pressure and desorbing the adsorbed toluene under low pressure. The PSA method utilizes such a property of the adsorbent. That is, by increasing the pressure inside the adsorption tower, the toluene contained in the hydrogen-containing gas is adsorbed by the adsorbent and removed, thereby obtaining high-purity hydrogen gas (purified gas). When the adsorption function of the adsorbent in the adsorption tower is reduced by adsorption, the pressure inside the adsorption tower is reduced to desorb the toluene adsorbed on the adsorbent, and at the same time, a part of the removed purified gas is reversed to remove the desorbed toluene from the adsorption tower, thereby regenerating the adsorption function of the adsorbent (at this time, the hydrogen-containing gas containing at least hydrogen and toluene discharged by removing toluene from the adsorption tower corresponds to the off-gas from the hydrogen purification unit 8).

[0025] A case where the TSA method is adopted as the removal method of the hydrogen purification unit 8 will be described. The adsorbent used in the TSA method has the property of adsorbing toluene contained in the hydrogen-containing gas at room temperature and desorbing the adsorbed toluene at high temperature. The TSA method utilizes such a property of the adsorbent. That is, by bringing the temperature inside the adsorption tower to room temperature, the toluene contained in the hydrogen-containing gas is adsorbed by the adsorbent and removed, thereby obtaining high-purity hydrogen gas (high-purity hydrogen). When the adsorption function of the adsorbent in the adsorption tower is reduced by adsorption, the toluene adsorbed by the adsorbent is desorbed by raising the temperature inside the adsorption tower, and the desorbed toluene is removed from the adsorption tower by backflowing a part of the removed high-purity hydrogen, thereby regenerating the adsorption function of the adsorbent (at this time, the hydrogen-containing gas containing at least hydrogen and toluene discharged by removing toluene from the adsorption tower corresponds to the off-gas from the hydrogen purification unit 8).

[0026] Next, there will be described characteristic parts of the above-mentioned hydrogen supply system 100. As shown in FIG.

[0027] The hydrogen supply unit 40 supplies hydrogen to the dehydrogenation reaction unit 3. When stopping the production of hydrogen-containing gas in the dehydrogenation reaction unit 3, the control unit 50 causes the hydrogen supply unit 40 to supply hydrogen to the dehydrogenation reaction unit 3. This allows the hydrogen supply unit 40 to introduce hydrogen into the dehydrogenation reaction unit 3 when the production is stopped.

[0028] Specifically, the hydrogen supply unit 40 includes a purge gas line L20 that supplies hydrogen-containing gas between the dehydrogenation reaction unit 3 and the gas-liquid separation unit 6 to the dehydrogenation reaction unit 3, and a valve 51 provided on the purge gas line L20. The purge gas line L20 extends from the line L3 to the line L2.

[0029] The hydrogen supply unit 40 also includes a purge gas line L25 that supplies the hydrogen-containing gas separated in the gas-liquid separation unit 6 to the dehydrogenation reaction unit 3, and a valve 52 provided on the purge gas line L25. The purge gas line L25 branches off from the line 5 and extends to the line L2. The purge gas line L25 may also branch off from the line L6.

[0030] The hydrogen supply unit 40 also includes a supply unit 55 that supplies hydrogen from an external source, and a purge gas line L15 that supplies hydrogen from the supply unit 55 to the dehydrogenation reaction unit 3. The purge gas line L15 is connected to the line L2. The supply unit 55 is composed of, for example, a tank that stores hydrogen, a pump that pressure-feeds the tank, and the like.

[0031] The hydrogen supply unit 40 may include at least one of the purge gas line L20 and the purge gas line L25. That is, the hydrogen supply unit 40 may include either one of the purge gas lines L20 and L25, or may include both the purge gas lines L20 and L25. The purge gas line L15 is not an essential structure, and may be installed as necessary or may be omitted.

[0032] Next, the operation of the control unit 50 will be described. When the dehydrogenation reaction is stopped, the control unit 50 closes the valve 54 of the line L2 to stop the supply of the raw material to the dehydrogenation reaction unit 3. At this stage, unreacted raw material and dehydrogenation products are present in the dehydrogenation reaction unit 3. In this state, the dehydrogenation reaction unit 3 is in a high temperature state.

[0033] Next, the control unit 50 controls the hydrogen supply unit 40 to supply hydrogen as a purge gas to the dehydrogenation reaction unit 3. Specifically, the control unit 50 opens the valve 51, extracts hydrogen-containing gas from between the dehydrogenation reaction unit 3 and the gas-liquid separation unit 6 through the purge gas line L20, and supplies the hydrogen-containing gas to the dehydrogenation reaction unit 3. The control unit 50 also opens the valve 52, extracts hydrogen-containing gas from the gas-liquid separation unit 6 through the purge gas line L25, and supplies the hydrogen-containing gas to the dehydrogenation reaction unit 3. The control unit 50 also starts the supply unit 55 to supply hydrogen to the dehydrogenation reaction unit 3 through the purge gas line L15. The control unit 50 may supply hydrogen-containing gas through either one of the purge gas lines L20 and L25, or may supply hydrogen-containing gas through both the purge gas lines L20 and L25. The control unit 50 does not necessarily supply hydrogen-containing gas through the purge gas line L15, and may perform the operation as needed.

[0034] As described above, the hydrogen supply unit 40 can purge the unreacted raw material and the dehydrogenation product remaining in the dehydrogenation reaction unit 3 with hydrogen. Here, the hydrogen that has passed through the dehydrogenation reaction unit 3 out of the hydrogen supplied by the hydrogen supply unit 40 may be discharged directly to the outside of the system. For example, a discharge line L35 that is open to the outside of the system is provided on the upper end side of the gas-liquid separation unit 6. The hydrogen that has passed through the dehydrogenation reaction unit 3 may be discharged from the discharge line L35 by opening the valve 56. After the liquid content (unreacted raw material, dehydrogenation product) of the dehydrogenation reaction unit 3 has been sufficiently purged, a part or all of the hydrogen that has passed through the dehydrogenation reaction unit 3 may be recycled. When recycling, the hydrogen that has passed through the dehydrogenation reaction unit 3 is returned to the dehydrogenation reaction unit 3 again.

[0035] There is no particular limitation on how long the control unit 50 continues to supply hydrogen from the hydrogen supply unit 40 after the dehydrogenation reaction unit 3 is stopped. For example, the control unit 50 may stop the supply of hydrogen from the hydrogen supply unit 40 when the temperature of the dehydrogenation reaction unit 3 drops to a predetermined temperature or lower, or may stop the supply of hydrogen from the hydrogen supply unit 40 after a predetermined time has elapsed.

[0036] As described above, the control unit 50 does not need to supply hydrogen from all of the purge gas lines L20, L25, and L15, and may supply hydrogen from at least one of the purge gas lines L20 and L25. The control unit 50 may switch which purge gas line L20, L25, and L15 to supply hydrogen from depending on the timing. For example, the control unit 50 may first supply hydrogen from the purge gas line L20, and when hydrogen runs out at that point, supply hydrogen from the purge gas line L25 or the like. The control unit 50 may supply hydrogen from the purge gas line L15 when hydrogen runs out in the purge gas lines L20 and L25. When the hydrogen supply unit 40 is provided with only one of the purge gas lines L20 and L25, the control unit 50 may not perform the switching as described above.

[0037] Next, the operation and effect of the hydrogen supply system 100 according to this embodiment will be described.

[0038] In the hydrogen supply system 100, the dehydrogenation reaction unit 3 obtains a hydrogen-containing gas by dehydrogenating a raw material containing a hydride. The dehydrogenation reaction unit 3 performs a dehydrogenation reaction with the dehydrogenation catalyst heated. When the generation of the hydrogen-containing gas in the dehydrogenation reaction unit 3 is stopped, the control unit 50 supplies hydrogen to the dehydrogenation reaction unit 3. This ensures that hydrogen is present in the dehydrogenation reaction unit 3 even when the operation is stopped. This prevents the dehydrogenation reaction unit 3 from being in a high-temperature state where no hydrogen is present, which would otherwise cause coke to deposit on the dehydrogenation catalyst. As a result, deterioration of the dehydrogenation catalyst in the dehydrogenation reaction unit 3 can be suppressed.

[0039] Furthermore, the hydrogen supply unit 40 supplies at least one of the hydrogen-containing gas between the dehydrogenation reaction unit 3 and the gas-liquid separation unit 6 that separates the dehydrogenation product from the hydrogen-containing gas, and the hydrogen-containing gas separated in the gas-liquid separation unit 6 that separates the dehydrogenation product from the hydrogen-containing gas, to the dehydrogenation reaction unit 3. In this manner, the hydrogen supply unit 40 supplies the hydrogen-containing gas upstream of the hydrogen purification unit 8 to the dehydrogenation reaction unit 3. This makes it unnecessary to take out hydrogen for suppressing deterioration of the dehydrogenation catalyst of the dehydrogenation reaction unit 3 from the hydrogen purification unit 8, and therefore it is possible to reduce the energy input to the hydrogen purification unit 8. As a result, it is possible to improve the system efficiency of the hydrogen supply system 100 while suppressing deterioration of the dehydrogenation catalyst of the dehydrogenation reaction unit 3.

[0040] When the hydrogen supply unit 40 supplies the hydrogen-containing gas between the dehydrogenation reaction unit 3 and the gas-liquid separation unit 6 to the dehydrogenation reaction unit 3, the hydrogen supply unit 40 can supply the hydrogen-containing gas before gas-liquid separation to the dehydrogenation reaction unit 3, thereby improving system efficiency. Also, when the gas-liquid separation unit 6 cannot fully function due to a malfunction of the liquid level gauge (rising or dropping of the liquid level causing hydrogen leakage, etc.), the hydrogen-containing gas from the purge gas line L20 can be supplied to the dehydrogenation reaction unit 3.

[0041] Furthermore, when the hydrogen supplying unit 40 supplies the hydrogen-containing gas separated in the gas-liquid separation unit 6 to the dehydrogenation reaction unit 3, the hydrogen supplying unit 40 can supply highly pure hydrogen from which dehydrogenation products have been removed (hydrogen with a higher purity than the hydrogen in the purge gas line L20) to the dehydrogenation reaction unit 3. Therefore, a good balance can be maintained between improved system efficiency and the use of highly pure hydrogen.

[0042] The hydrogen supply unit 40 may supply hydrogen from an external source. In this case, the hydrogen supply unit 40 can supply hydrogen without worrying about the remaining amount of hydrogen present in the system. Even when the hydrogen-containing gas between the dehydrogenation reaction unit 3 and the gas-liquid separation unit 6 and / or the hydrogen-containing gas separated in the gas-liquid separation unit 6 is insufficient as hydrogen for suppressing deterioration of the dehydrogenation catalyst in the dehydrogenation reaction unit 3, or when the pressure loss becomes large and the hydrogen-containing gas cannot be supplied to the dehydrogenation reaction unit 3 with the purge gas pressure of the purge gas lines L20 and L25, the deterioration of the dehydrogenation catalyst can be effectively suppressed by supplying hydrogen from an external source. In addition, hydrogen may be supplied from an external source for initial start-up or maintenance.

[0043] The present invention is not limited to the above-described embodiment. For example, in the above-described embodiment, a hydrogen station for an FVC is exemplified as a hydrogen supply system, but the hydrogen supply system may be a hydrogen supply system for a distributed power source such as a home power source or an emergency power source.

[0044] The hydrogen supply system 100 may have, as the hydrogen supply unit 40, at least one of the purge gas lines L20 and L25. [Explanation of symbols]

[0045] 3...dehydrogenation reaction section, 6...gas-liquid separation section, 8...hydrogen purification section, 40...hydrogen supply section, 50...control section, 100...hydrogen supply system.

Claims

1. A hydrogen supply system that supplies hydrogen, a dehydrogenation reaction section for obtaining a hydrogen-containing gas by dehydrogenating a raw material containing a hydride; a hydrogen supplying section for supplying hydrogen to the dehydrogenation reaction section; A control unit that controls the hydrogen supply system, the control unit causes the hydrogen supply unit to supply hydrogen to the dehydrogenation reaction unit when stopping the generation of the hydrogen-containing gas in the dehydrogenation reaction unit; The hydrogen supply unit is the hydrogen-containing gas between the dehydrogenation reaction section and a gas-liquid separation section that separates a dehydrogenation product from the hydrogen-containing gas; and a hydrogen supply system which supplies at least one of the hydrogen-containing gas between a gas-liquid separation section which separates a dehydrogenation product from the hydrogen-containing gas and a first compression section which compresses the hydrogen-containing gas separated in the gas-liquid separation section to the dehydrogenation reaction section.

2. The hydrogen supply system according to claim 1 , wherein the hydrogen supply unit further supplies hydrogen from an external source to the dehydrogenation reaction unit.

3. A hydrogen supply system as described in claim 2, wherein the control unit switches the supply of the hydrogen-containing gas between the dehydrogenation reaction unit and the gas-liquid separation unit, and the supply of hydrogen from the outside to the dehydrogenation reaction unit.

4. A hydrogen supply system as described in claim 3, wherein the control unit switches the supply of the hydrogen-containing gas between the dehydrogenation reaction unit and the gas-liquid separation unit, the hydrogen-containing gas between the gas-liquid separation unit and the first compression unit, and hydrogen from the outside to the dehydrogenation reaction unit.

5. A hydrogen supply system as described in claim 4, wherein the control unit supplies hydrogen from the outside to the dehydrogenation reaction unit when the hydrogen-containing gas between the dehydrogenation reaction unit and the gas-liquid separation unit, and the hydrogen-containing gas between the gas-liquid separation unit and the first compression unit, are exhausted.

6. A hydrogen supply system as described in claim 5, wherein the gas-liquid separation section is provided with an exhaust line for discharging hydrogen supplied by the hydrogen supply section that has passed through the dehydrogenation reaction section outside the system.

7. Further comprising a second compression section which supplies the raw material to the dehydrogenation reaction section, 7. The hydrogen supply system according to claim 6, wherein the control unit closes a valve between the second compression unit and the dehydrogenation reaction unit when the dehydrogenation reaction is stopped.

8. A hydrogen supply system as described in claim 7, further comprising a heat exchange section which performs heat exchange between the raw material supplied to the dehydrogenation reaction section and the hydrogen-containing gas obtained by the dehydrogenation reaction, and a heating section which heats the dehydrogenation reaction section using a heat medium.

9. A dehydrogenation reaction section that obtains a hydrogen-containing gas by dehydrogenating a raw material containing a hydride, and a control device that controls the supply of hydrogen to the dehydrogenation reaction section through a purge gas line, When the generation of the hydrogen-containing gas in the dehydrogenation reaction section is stopped, a first purge gas line for passing the hydrogen-containing gas between the dehydrogenation reaction section and a gas-liquid separation section for separating a dehydrogenation product from the hydrogen-containing gas; and a control device which supplies the hydrogen-containing gas between a gas-liquid separation section which separates a dehydrogenation product from the hydrogen-containing gas and a first compression section which compresses the hydrogen-containing gas separated in the gas-liquid separation section to the dehydrogenation reaction section via at least one of a second purge gas line.

10. A control device as described in claim 9, which controls the supply of hydrogen from outside to the dehydrogenation reaction section via a third purge gas line when the generation of the hydrogen-containing gas in the dehydrogenation reaction section is stopped.

11. A control device as described in claim 10, which controls hydrogen from the outside to be supplied to the dehydrogenation reaction section via the third purge gas line depending on the remaining amount of hydrogen in the first purge gas line and the second purge gas line.

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