JP6618394B2 - Hydrogen utilization system - Google Patents

Description

  The present invention relates to a hydrogen utilization system.

  In recent years, energy environments using hydrogen, such as vehicles equipped with fuel cells, have been emphasized and are being developed. Hydrogen is produced by various techniques such as water electrolysis, fossil energy or methanol reforming. Here, if hydrogen can be efficiently converted into energy and used as a larger energy, the energy utilization efficiency in the hydrogen utilization environment will be dramatically improved.

  Further, the produced hydrogen can be stored in a high-pressure tank, a liquefaction tank, or a hydrogen storage alloy, and can be stored by converting into an organic hydride, methanol, or the like and liquefying.

  As a system for producing fuel hydrogen by storing hydrogen as described above, for example, a hydrogen production apparatus for producing hydrogen and a fuel form using hydrogen produced by the hydrogen production apparatus as fuel are used. Two or more hydrogen fuel production apparatuses to be produced and a hydrogen fuel production system characterized in that there are two or more types of fuel produced by the hydrogen fuel production apparatus (see, for example, Patent Document 1) . In this hydrogen fuel production system, it is possible to efficiently produce each hydrogen fuel according to the demand.

JP 2005-350299 A

  By the way, a hydrogen production apparatus for producing hydrogen is installed in an oil refining factory or the like, and the produced hydrogen is used for hydrodesulfurization of each petroleum fraction. The demand for hydrogen for hydrodesulfurization has decreased along with the reduction in gasoline demand and energy savings such as the use of off-gas at factories. It is falling.

  Normally, the hydrogen production efficiency is highest when the hydrogen production apparatus is operated at the rated load, and the load factor is lowered and the hydrogen production efficiency is also lowered. Therefore, it is preferable to maintain the hydrogen production efficiency at a high load from the viewpoint of effectively using the fuel used when producing hydrogen. As a method for maintaining the hydrogen production efficiency at a high load, a method of storing surplus hydrogen as described above without reducing the load even when the demand for hydrogen decreases can be considered.

  However, in general factories, the method of storing surplus hydrogen as described above is not currently employed because of problems such as installation space and inventory costs. Furthermore, it is preferable to effectively use surplus hydrogen by increasing the utilization efficiency of hydrogen as energy rather than simply storing surplus hydrogen.

  The present invention has been made in view of the above, and an object of the present invention is to provide a hydrogen utilization system capable of effectively using surplus hydrogen by improving the utilization efficiency of hydrogen as energy.

The above problem is solved by, for example, the following means.
<1> Hydrogen production means for producing hydrogen using the supplied fuel gas, hydrogen consumption means for consuming at least part of the hydrogen produced by the hydrogen production means, and produced by the hydrogen production means A solid polymer fuel cell (hereinafter, also referred to as “PEFC”) that generates power by supplying surplus hydrogen that is not consumed by the hydrogen consuming means. A hydrogen utilization system in which an amount of the fuel gas is supplied and the hydrogen production means produces hydrogen at a rated load.

  The hydrogen utilization system according to this embodiment includes a hydrogen consuming unit that supplies and consumes at least a part of the produced hydrogen, and a PEFC that generates electricity using surplus hydrogen that is not consumed by the hydrogen consuming unit. Therefore, it is not necessary to vary the load during operation in the hydrogen production means according to the hydrogen demand of the hydrogen consumption means, hydrogen can be produced at a rated load with high hydrogen production efficiency, and surplus hydrogen is used. Power can be generated with PEFC.

  Furthermore, in the hydrogen utilization system according to the present embodiment, surplus hydrogen is used to generate power with PEFC. Therefore, surplus hydrogen can be used by increasing the utilization efficiency of hydrogen as energy compared to the case of simply storing surplus hydrogen. Can be used effectively.

  <2> The apparatus further comprises a purifier that purifies the hydrogen produced by the hydrogen producing means in advance, and the hydrogen consuming means and the polymer electrolyte fuel cell are supplied with hydrogen purified by the purifier < 1> The hydrogen utilization system described in 1>.

  High purity is required for hydrogen supplied to PEFC, and high purity is also required for hydrogen supplied to hydrogen consuming means such as hydrodesulfurization equipment. In the hydrogen utilization system according to this embodiment, the hydrogen produced before being supplied to the PEFC and hydrogen consuming means is purified in advance to maintain high power generation efficiency in the PEFC and maintain and improve the durability of the fuel cell. Thus, high-purity hydrogen suitable for hydrogen consuming means such as a hydrodesulfurization apparatus can be obtained.

  <3> The hydrogen utilization system according to <2>, wherein electric power obtained by power generation in the polymer electrolyte fuel cell is supplied to the purifier.

  In the hydrogen utilization system according to the present embodiment, by supplying the power obtained by the power generation in the PEFC to the refining device, it is possible to cover part or all of the necessary power in the refining device, and from the external power system The amount of power supplied to the refining device can be reduced.

  <4> The hydrogen utilization system according to any one of <1> to <3>, wherein the hydrogen production means reforms the fuel gas to produce hydrogen.

  In the hydrogen utilization system according to this embodiment, hydrogen is efficiently produced by the reforming reaction of the fuel gas in the hydrogen production means.

  ADVANTAGE OF THE INVENTION According to this invention, the utilization efficiency as hydrogen energy can be improved, and the hydrogen utilization system which can utilize surplus hydrogen effectively can be provided.

It is a system configuration figure showing a schematic structure of a hydrogen utilization system concerning an embodiment of the present invention. It is a graph which shows the simulation result of the primary energy consumption in systems 1-5.

  Hereinafter, embodiments of the hydrogen utilization system of the present invention will be specifically described with reference to the drawings. However, the present invention is not limited to the embodiments shown below.

  An embodiment of a hydrogen utilization system according to the present invention will be described with reference to FIG. The hydrogen utilization system 100 according to the present embodiment performs hydrogen desulfurization using a hydrogen production apparatus 1 (hydrogen production means) that produces hydrogen using a fuel gas such as city gas and a part of the produced hydrogen. A hydrodesulfurization device 3 (hydrogen consuming means) and a PEFC 4 (solid polymer fuel cell) that generates electricity by supplying surplus hydrogen that is not consumed by the hydrodesulfurization device 3 are provided. Furthermore, a certain amount of fuel gas is supplied to the hydrogen production apparatus 1 and the hydrogen production apparatus 1 performs hydrogen production at a rated load.

  The hydrogen utilization system 100 according to the present embodiment includes a hydrodesulfurization apparatus 3 that performs hydrodesulfurization by supplying at least a part of the produced hydrogen, and a PEFC 4 that generates power using surplus hydrogen. Therefore, it is not necessary to vary the load during operation in the hydrogen production device 1 according to the hydrogen demand of the hydrodesulfurization device 3, hydrogen can be produced at a rated load with high hydrogen production efficiency, and surplus Electricity can be generated by PEFC4 using hydrogen.

  Furthermore, in the hydrogen utilization system 100 according to the present embodiment, since the surplus hydrogen is used to generate power in the PEFC 4, the utilization efficiency of hydrogen as energy is increased as compared with the case where the surplus hydrogen is simply stored. Surplus hydrogen can be used effectively.

The hydrogen utilization system 100 according to the present embodiment further includes a purification device 2 that purifies hydrogen produced in the hydrogen production device 1 in advance, and supplies high-purity hydrogen to the hydrodesulfurization device 3 and the PEFC 4. Can do.
Hereinafter, each configuration of the hydrogen utilization system 100 will be described.

  The hydrogen production apparatus 1 is not particularly limited as long as it is an apparatus that produces hydrogen using a fuel gas such as city gas, and examples thereof include a reformer that reforms a fuel gas to produce hydrogen.

  Examples of the fuel gas include hydrocarbon gas. Examples of the hydrocarbon gas include natural gas, LP gas (liquefied petroleum gas), coal reformed gas, lower hydrocarbon gas, and biogas. Examples of the lower hydrocarbon gas include lower hydrocarbons having 4 or less carbon atoms such as methane, ethane, ethylene, propane, butane, and methane is particularly preferable. The hydrocarbon gas may be a mixture of the above-described lower hydrocarbon gas, or a gas such as natural gas, city gas, LP gas, or the like.

  In this embodiment, as shown in FIG. 1, city gas, which is an example of fuel gas, is supplied to the hydrogen production apparatus 1 through the city gas supply path 11.

  When the hydrogen production apparatus 1 is a reformer, examples of reforming of city gas (fuel gas) include steam reforming, carbon dioxide reforming, partial oxidation reforming, and shift reaction reforming. When steam reforming, carbon dioxide reforming, and partial oxidation reforming are performed in the reformer, steam, carbon dioxide, and oxygen may be supplied to the reformer, respectively. The shift reaction reforming is a reaction that occurs accompanying steam reforming, and a CO converter may be provided together with the reformer, and the shift reaction reforming may be performed in the CO converter.

  In the hydrogen utilization system 100 according to the present embodiment, a certain amount of city gas is supplied to the hydrogen production apparatus 1, and the hydrogen production apparatus 1 performs hydrogen production at a rated load. Therefore, it is not necessary to vary the load during operation of the hydrogen production means according to the hydrogen demand of the hydrogen consumption means, and hydrogen can be produced at a rated load with high hydrogen production efficiency.

  When the load at the time of operation in the hydrogen production means is changed according to the amount of hydrogen demand of the hydrogen consumption means, the hydrogen production efficiency is lowered when the load is low, and the hydrogen production cost is increased. On the other hand, by operating the hydrogen production apparatus 1 efficiently at the rated load regardless of the hydrogen demand of the hydrodesulfurization apparatus 3 (hydrogen consumption means), the hydrogen production cost is lower than when the load is varied.

  In addition, since the hydrogen production apparatus 1 is operated at the rated load regardless of the hydrogen demand of the hydrodesulfurization apparatus 3, a certain amount of city gas is supplied through the city gas supply path 11. Therefore, it is not necessary to adjust the supply amount of city gas according to the hydrogen demand of the hydrodesulfurization apparatus 3.

  The purification device 2 is a device that is located downstream of the hydrogen production device 1 and purifies the hydrogen produced by the hydrogen production device 1 in advance. Hydrogen produced by the hydrogen production apparatus 1 is supplied to the purification apparatus 2 through the hydrogen supply path 12.

  High purity is required for the hydrogen supplied to the hydrodesulfurization unit 3 and the PEFC 4. In the hydrogen utilization system 100 according to the present embodiment, the hydrogen produced in the hydrodesulfurization apparatus 3 and the PEFC 4 before being purified is purified in advance, so that the power generation efficiency in the PEFC 4 is maintained high, and the durability of the PEFC 4 is increased. It can be maintained and improved, and high-purity hydrogen suitable for hydrodesulfurization in the hydrodesulfurization apparatus 3 can be obtained.

  The hydrogen produced by the hydrogen production apparatus 1 includes impurities contained in the city gas or impurities produced by the hydrogen production apparatus 1, for example, hydrocarbon gas such as methane gas, carbon monoxide, Examples include carbon dioxide, hydrogen sulfide, sulfur dioxide, and the like.

  The purification apparatus 2 may be appropriately selected from an apparatus that can remove impurities mixed with hydrogen. As a specific example of the purification apparatus 2, a pressure swing adsorption (PSA) apparatus that performs gas separation by attaching and detaching gas components when pressure application and pressure reduction are repeated using a pressure fluctuation adsorption method (PSA method), carbon dioxide is selected. And carbon dioxide separation membranes for separation, and desulfurization agents such as activated carbon or alloy particles that adsorb sulfur.

  Carbon dioxide absorbed by the PSA device or carbon dioxide separated by the carbon dioxide separation membrane may be recovered. When the hydrogen production apparatus 1 is a reformer, the amount of carbon dioxide generated together with hydrogen is increased by producing hydrogen at a rated load, so that the increased carbon dioxide is recovered. It is preferably used for quality and chemical synthesis, or for industrial use.

  Further, since the hydrogen production apparatus 1 is operated at the rated load regardless of the hydrogen demand of the hydrodesulfurization apparatus 3, a certain amount of hydrogen is produced and a certain amount of hydrogen is supplied to the purification device 2. Therefore, the load of the purification apparatus 2 is constant, and it is not necessary to change the load of the purification apparatus 2 according to the amount of hydrogen supplied to the purification apparatus 2.

  Hydrogen whose purity has been increased by the refining apparatus 2 is supplied to the hydrodesulfurization apparatus 3 through the hydrogen supply path 13 and supplied to the PEFC 4 through the hydrogen supply path 14.

  The hydrodesulfurization apparatus 3 is an apparatus for performing hydrodesulfurization of petroleum fractions using hydrogen supplied through the hydrogen supply path 13, and hydrogen consuming means for consuming hydrogen produced by the hydrogen production apparatus 1. It is an example. By performing hydrodesulfurization, sulfur contained in the petroleum fraction can be removed, and the petroleum fraction is refined to a high purity and supplied to the outside of the system through the petroleum fraction supply path 16. The oil fraction is supplied to the hydrodesulfurization apparatus 3 through the oil fraction supply path 15.

  Examples of petroleum fractions include fractions separated from crude oil by a difference in boiling points in a distillation apparatus, such as natural gas, petroleum gas, gasoline, kerosene, light oil, and heavy oil.

  The hydrodesulfurization apparatus 3 is, for example, a catalyst (desulfurization catalyst) for reacting sulfur contained in a petroleum fraction with hydrogen to convert it into hydrogen sulfide, and an adsorption for absorbing and removing the converted hydrogen sulfide. An agent (desulfurization agent). As a result, sulfur such as carbonyl sulfide (COS), mercaptans, dimethyl sulfide (DMS), and thiophenes can be reacted with hydrogen to be converted into hydrogen sulfide, and then the converted hydrogen sulfide can be removed. .

  The hydrogen consuming means is not limited to the hydrodesulfurization apparatus described above, and examples thereof include a petrochemical product manufacturing apparatus and an ammonia synthesis apparatus.

  In the hydrogen utilization system 100 according to the present embodiment, hydrogen is supplied to the hydrodesulfurization device 3 according to the hydrogen demand in the hydrodesulfurization device 3, and surplus generated according to the hydrogen demand in the hydrodesulfurization device 3. Hydrogen is supplied to PEFC4.

  The PEFC 4 is a battery that generates power using surplus hydrogen supplied through the hydrogen supply path 14. Surplus hydrogen is supplied to the anode side through the hydrogen supply path 14.

The PEFC 4 has a structure in which a cell in which a polymer electrolyte membrane is sandwiched between an anode electrode (fuel electrode) and a cathode electrode (oxygen electrode) is further sandwiched between separators. When hydrogen is supplied to the anode side of the PEFC 4, hydrogen ions are generated as shown in the following reaction (a).
H ₂ → 2H ⁺ + 2e ⁻ (a)

In PEFC4, the generated hydrogen ions move to the cathode side through the polymer electrolyte membrane, and as shown in the following reaction (b), a reaction occurs in which the hydrogen ions react with oxygen to generate water on the cathode side. ,Generate electricity.
1 / 2O ₂ + 2H ⁺ + e ⁻ → H ₂ O (b)

  The electric power obtained by the power generation in the PEFC 4 is supplied to the refining device 2 via the electric power system 21, for example. Thereby, a part or all of electric power required in the refiner | purifier 2 can be covered, and the electric energy supplied to the refiner | purifier 2 from an external electric power grid | system can be reduced. In addition, the supply destination of the electric power obtained by the power generation in the PEFC 4 is not limited to the refining device 2, and may be supplied outside the system, for example, or may be stored by storing a power storage device.

  Since the hydrogen production apparatus 1 is operated at a rated load and the generated surplus hydrogen is used for power generation in the PEFC 4, inexpensive electric power can be secured.

  Furthermore, hydrogen is supplied to PEFC 4 and reacts to obtain thermal energy as well as electrical energy. By exchanging this thermal energy with water, it can be taken out as heated water (hot water). The generated hot water is relatively low at about 60 ° C. and is difficult to use industrially. For example, it can be supplied to a combustion facility such as a steam boiler or used for binary power generation.

  By supplying the generated warm water to a combustion facility such as a steam boiler, the warm water exchanges heat with the heat obtained by the combustion to become steam, and the energy efficiency can be improved by effectively using the thermal energy of the warm water. In addition, by performing binary power generation that heats and evaporates a liquid having a lower boiling point than water, for example, an organic substance such as pentane and isobutane, alternative chlorofluorocarbon, or a mixture of ammonia and water, and rotates the turbine with the steam, Low temperature hot water can be used effectively.

  The surplus hydrogen generated according to the amount of hydrogen demand in the hydrodesulfurization device 3 may be supplied to the PEFC 4, or may be partially stored in a high-pressure tank, a liquefaction tank, a hydrogen storage alloy, or the like. May be.

  Next, in the hydrogen utilization system 100 according to the present embodiment, a simulation result for estimating the primary energy consumption (converted value) is shown below in comparison with the conventional system. The system 1 and the systems 4 and 5 will be exemplified as conventional systems, and the systems 2 and 3 will be described as examples of the hydrogen utilization system according to an embodiment of the present invention.

First, in systems 1 to 5, it was assumed that city gas was used as a fuel gas for producing hydrogen, and the amount of hydrogen required for hydrodesulfurization was 1000 Nm ³ / h. Moreover, the primary energy conversion value of hydrogen was 10.8 MJ / Nm ^3, and the primary energy conversion value of city gas was 40.6 MJ / Nm ³ .

(System 1)
As a system 1, a system including a hydrogen production apparatus that supplies city gas to produce hydrogen and a hydrodesulfurization apparatus that performs hydrodesulfurization using the produced hydrogen will be considered. In the system 1, hydrogen necessary for hydrodesulfurization is produced without excess and deficiency, and the hydrogen production apparatus is operated at a load lower than the rated load. At this time, assuming that the hydrogen production efficiency in the hydrogen production apparatus is 0.7 (70%), the amount of city gas necessary for producing hydrogen necessary for hydrodesulfurization without excess or deficiency is calculated as follows: Is done.
^{1000 (Nm 3 /h)×10.8(MJ/Nm 3) /0.7/40.6} (MJ / Nm 3) ≒ 380 (Nm 3 / h)

As described above, the annual primary energy consumption (converted value) in the system 1 is calculated as follows.
^{380 (Nm 3 /h)×40.6(MJ/Nm 3) ×} 24 (h / day) × 365 (day / ^{year) × 10 -3 (GJ / MJ} ) ≒ 135149 (GJ / year)

(System 2)
As a system 2, a system including a hydrogen production apparatus that supplies hydrogen by supplying city gas, a hydrodesulfurization apparatus that performs hydrodesulfurization using the produced hydrogen, and a PEFC that generates power using surplus hydrogen will be studied. . In this system, the hydrogen production apparatus is operated at a rated load that is a load higher than that of the system 1. The hydrogen production efficiency in the hydrogen production apparatus during the rated load operation is assumed to be 0.75 (75%), and the amount of surplus hydrogen is assumed to be 500 Nm ³ / h. The amount of natural gas needed to produce the required hydrogen 1000 Nm ³ / h and excess hydrogen 500 Nm ³ / h for the hydrodesulfurization is calculated as follows.
^{1500 (Nm 3 /h)×10.8(MJ/Nm 3) /0.75/40.6} (MJ / Nm 3) ≒ 532 (Nm 3 / h)

As described above, the annual primary energy consumption (city gas consumption) in the system 2 is calculated as follows.
^{532 (Nm 3 /h)×40.6(MJ/Nm 3) ×} 24 (h / day) × 365 (day / ^{year) × 10 -3 (GJ / MJ} ) ≒ 189209 (GJ / year)

Here, in system 2, surplus hydrogen of 500 Nm ³ / h is produced, and surplus hydrogen is supplied to PEFC to generate power. Therefore, the annual primary energy consumption (converted value) in the system 2 needs to subtract the primary energy amount (converted value) of the generated power from the primary energy consumption (city gas consumption).

The power generation efficiency (LHV) of PEFC is 0.55 (55%), and the primary energy conversion value of electric power is 9.63 GJ / MWh. At this time, the power generation amount of PEFC (GJ / year, MW, MWh / year) is as follows.
PEFC power generation (GJ / year): 500 (Nm ³ /h)×10.8 (MJ / Nm ³ ) × 24 (h / day) × 365 (day / year) × 0.55 × 10 ^{− 3} (GJ / MJ) = 26017.2 (GJ / year)
PEFC power generation (MW) ... 500 (Nm ³ /h)×10.8 (MJ / Nm ³ ) ÷ 3600 (seconds / h) × 0.55 = 0.825 (MW)
PEFC power generation (MWh / year): 0.825 (MW) x 24 (h / day) x 365 (day / year) ≒ 7227 (MWh / year)

Based on the calculated power generation amount (MWh / year) of PEFC, the primary energy (converted value) of the generated power is calculated as follows.
7227 (MWh / year) × 9.63 (GJ / MWh) ≈69596 (GJ / year)

As described above, the annual primary energy consumption (converted value) in the system 2 and the reduction rate of the primary energy consumption (converted value) for the system 1 are calculated as follows.
Annual primary energy consumption (converted value) 189209 (GJ / year) -69596 (GJ / year) = 119612 (GJ / year)
Reduction rate of primary energy consumption (converted value) with respect to system 1 [135149 (GJ / year) -119612 (GJ / year)] / 135149 (GJ / year) ≈11.5%

(System 3)
As a system 3, a system including a hydrogen production apparatus that produces hydrogen by supplying city gas, a hydrodesulfurization apparatus that performs hydrodesulfurization using the produced hydrogen, and a PEFC that generates power using surplus hydrogen will be studied. . In this system, it is assumed that the hydrogen production device is operated at a rated load, which is a higher load than system 1, and the hydrogen production efficiency during rated load operation is 0.80 (80%) higher than that of system 2, and surplus The amount of hydrogen is assumed to be 500 Nm ³ / h. The amount of natural gas needed to produce the required hydrogen 1000 Nm ³ / h and excess hydrogen 500 Nm ³ / h for the hydrodesulfurization is calculated as follows.
^{1500 (Nm 3 /h)×10.8(MJ/Nm 3) /0.80/40.6} (MJ / Nm 3) ≒ 499 (Nm 3 / h)

As described above, the annual primary energy consumption (city gas consumption) in the system 3 is calculated as follows.
^{499 (Nm 3 /h)×40.6(MJ/Nm 3) ×} 24 (h / day) × 365 (day / ^{year) × 10 -3 (GJ / MJ} ) ≒ 189209 (GJ / year) ≒ 177472 ( GJ / year)

Here, in the system 3, surplus hydrogen of 500 Nm ³ / h is produced, and surplus hydrogen is supplied to the PEFC to generate power. Therefore, like the system 2, the annual primary energy consumption (converted value) in the system 3 needs to subtract the primary energy amount (converted value) of the generated electric power from the primary energy consumption (city gas consumption). As in system 2, the power generation efficiency (LHV) of PEFC is 0.55 (55%), and the primary energy conversion value of power is 9.63 GJ / MWh. At this time, the power generation amount of PEFC (GJ / year, MW, MWh / year) is 26017.2 (GJ / year), 0.825 (MW), 7227 (MWh / year), as in the case of system 2, and is calculated. Based on the generated power (MWh / year) of the PEFC, the primary energy (converted value) of the generated electric power is 69596 (GJ / year) as in the system 2.

As described above, the annual primary energy consumption (converted value) in the system 3 and the reduction rate of the primary energy consumption (converted value) for the system 1 are calculated as follows.
Annual primary energy consumption (converted value) 177472 (GJ / year) -69596 (GJ / year) = 107876 (GJ / year)
Reduction rate of primary energy consumption (converted value) for system 1 [135149 (GJ / year) -107876 (GJ / year)] / 135149 (GJ / year) ≈20.2%

(System 4)
Next, as a system 4, a system including a hydrogen production apparatus that supplies hydrogen by supplying city gas, a hydrodesulfurization apparatus that performs hydrodesulfurization using the produced hydrogen, and a storage tank that stores surplus hydrogen is studied. To do. In this system, the hydrogen production apparatus is operated at a load higher than that of the system 1, and in this system, the hydrogen production apparatus is operated at a rated load that is a load higher than that of the system 1. At this time, the hydrogen production efficiency in the hydrogen production apparatus is assumed to be 0.75 (75%), and the amount of surplus hydrogen is assumed to be 500 Nm ³ / h. Similar to system 2, the amount of the city gas required to produce the required hydrogen 1000 Nm ³ / h and excess hydrogen 500 Nm ³ / h for the hydrodesulfurization is calculated as follows.
^{1500 (Nm 3 /h)×10.8(MJ/Nm 3) /0.75/40.6} (MJ / Nm 3) ≒ 532 (Nm 3 / h)

As described above, the annual primary energy consumption (city gas consumption) in the system 4 is calculated as follows.
^{532 (Nm 3 /h)×40.6(MJ/Nm 3) ×} 24 (h / day) × 365 (day / ^{year) × 10 -3 (GJ / MJ} ) ≒ 189209 (GJ / year)

Here, in the system 4, surplus hydrogen of 500 Nm ³ / h is produced, and surplus hydrogen is stored in a storage tank. Therefore, the annual primary energy consumption (converted value) in the system 4 needs to subtract the primary energy amount (hydrogen storage amount) of hydrogen stored from the primary energy consumption (city gas consumption amount).

The primary energy (hydrogen storage amount) of hydrogen stored is calculated as follows.
^{500 (Nm 3 /h)×10.8(MJ/Nm 3) ×} 24 (h / day) × 365 (day / ^{year) × 10 -3 (GJ / MJ} ) /0.75=63072 (GJ / year )

As described above, the annual primary energy consumption (converted value) in the system 4 and the reduction rate of the primary energy consumption (converted value) for the system 1 are calculated as follows.
Annual primary energy consumption (converted value) ... 189209 (GJ / year) -63072 (GJ / year) = 126137 (GJ / year)
Reduction rate of primary energy consumption (converted value) with respect to the system 1 [135149 (GJ / year) -126137 (GJ / year)] / 135149 (GJ / year) ≈6.7%

(System 5)
Next, as a system 5, a hydrogen production apparatus that supplies city gas to produce hydrogen, a hydrodesulfurization apparatus that performs hydrodesulfurization using the produced hydrogen, and a storage tank that stores surplus hydrogen are studied. To do. In this system, it is assumed that the hydrogen production apparatus is operated at a rated load, which is a higher load than system 1, and that the hydrogen production efficiency at the rated load is 0.80 (80%) higher than that of system 2, The amount is assumed to be 500 Nm ³ / h. The amount of natural gas needed to produce the required hydrogen 1000 Nm ³ / h and excess hydrogen 500 Nm ³ / h for the hydrodesulfurization is calculated as follows.
^{1500 (Nm 3 /h)×10.8(MJ/Nm 3) /0.80/40.6} (MJ / Nm 3) ≒ 499 (Nm 3 / h)

As described above, the annual primary energy consumption (city gas consumption) in the system 3 is calculated as follows.
^{499 (Nm 3 /h)×40.6(MJ/Nm 3) ×} 24 (h / day) × 365 (day / ^{year) × 10 -3 (GJ / MJ} ) ≒ 189209 (GJ / year) ≒ 177472 ( GJ / year)

Here, in the system 5, surplus hydrogen of 500 Nm ³ / h is produced, and surplus hydrogen is stored in a storage tank. Therefore, the annual primary energy consumption (converted value) in the system 5 needs to subtract the primary energy amount (hydrogen storage amount) of hydrogen stored from the primary energy consumption (city gas consumption amount).

The primary energy (hydrogen storage amount) of hydrogen stored is calculated as follows.
^{500 (Nm 3 /h)×10.8(MJ/Nm 3) ×} 24 (h / day) × 365 (day / ^{year) × 10 -3 (GJ / MJ} ) /0.8=59130 (GJ / year )

As described above, the annual primary energy consumption (converted value) in the system 5 and the reduction rate of the primary energy consumption (converted value) for the system 1 are calculated as follows.
Annual primary energy consumption (converted value) 177472 (GJ / year) -59130 (GJ / year) = 118342 (GJ / year)
Reduction rate of primary energy consumption (converted value) for system 1 [135149 (GJ / year) -118342 (GJ / year)] / 135149 (GJ / year) ≈12.4%

  The simulation results in the above systems 1 to 5 are summarized as shown in Table 1 and FIG.

  Comparing the primary energy consumption (converted value) for each of the systems 1 to 5, the system 2 (hydrogen production efficiency 75%) with PEFC has a value higher than the system 4 (hydrogen production efficiency 75%) that stores surplus hydrogen. The primary energy consumption was low. Also, the system 3 (PE production efficiency 80%) equipped with PEFC has a lower value than the system 5 (hydrogen production efficiency 80%) that stores surplus hydrogen, and the primary energy consumption has been reduced. Therefore, in systems 2 and 3, it was shown that the utilization efficiency of hydrogen as energy is increased and surplus hydrogen is effectively utilized.

1 Hydrogen production equipment (hydrogen production means)
2 Refining equipment 3 Hydrodesulfurization equipment (hydrogen consumption means)
4 PEFC (Polymer Fuel Cell)
11 City gas supply path 12, 13, 14 Hydrogen supply path 15, 16 Petroleum fraction supply path 21 Electric power system 100 Hydrogen utilization system

Claims (4)

Hydrogen production means for producing hydrogen using the supplied fuel gas;
Hydrogen consuming means for consuming at least part of the hydrogen produced by the hydrogen producing means;
Of the hydrogen produced by the hydrogen production means, a solid polymer fuel cell that generates power by supplying surplus hydrogen that is not consumed by the hydrogen consumption means;
With
The said hydrogen production means, a certain amount of the fuel gas is supplied, and the hydrogen production means have lines of hydrogen production at rated load,
The hydrogen consumption means is a hydrodesulfurization apparatus, a petrochemical product manufacturing apparatus or an ammonia synthesis apparatus,
The hydrogen consumption system and the polymer electrolyte fuel cell are a hydrogen utilization system located downstream of the hydrogen production means .   2. The apparatus according to claim 1, further comprising a refining device that purifies the hydrogen produced by the hydrogen producing unit in advance, wherein the hydrogen consuming unit and the polymer electrolyte fuel cell are supplied with hydrogen purified by the refining device. The hydrogen utilization system described.   The hydrogen utilization system according to claim 2, wherein electric power obtained by power generation in the polymer electrolyte fuel cell is supplied to the purifier.   The hydrogen utilization system according to any one of claims 1 to 3, wherein the hydrogen production means reforms the fuel gas to produce hydrogen.