JP5428531B2 - Hydrogen production equipment - Google Patents

Description

  The present invention relates to a hydrogen production apparatus for producing a hydrogen-rich reformed gas by steam reforming a hydrocarbon-based fuel such as city gas or LPG.

  The fuel cell power generation system mainly includes a hydrogen production apparatus that produces hydrogen-rich reformed gas and a fuel cell that generates power using the produced hydrogen-rich reformed gas.

  Hydrogen production equipment is reformed with hydrogen, methane, carbon monoxide (contains about 10%), carbon dioxide, and steam by steam reforming reaction using city gas, LPG and other hydrocarbon fuels and water. A carbon monoxide having a reforming section for generating a gas and a heating means such as a burner for heating the reforming section, and removing carbon monoxide having a poisoning action on the fuel cell, if necessary. It consists of a removal unit. The reformed gas produced by the hydrogen production apparatus is supplied to the anode of the fuel cell, and the fuel cell generates electricity by electrochemically reacting hydrogen in the reformed gas and oxygen in the air. Yes.

  Here, of the reformed gas supplied to the fuel cell, the reformed gas containing hydrogen that has not been consumed by the fuel cell is discharged as off-gas, but this off-gas is returned to the hydrogen production apparatus and is used as fuel for the heating means. It is used as a gas.

  At this time, in order for the carbon monoxide removal unit that removes carbon monoxide from the reformed gas to exert its effect, the carbon monoxide removal unit needs to be maintained at a temperature within a certain range. When the fuel cell power generation system is operating stably, the required temperature is reached due to the heat carried along with the reformed gas. However, immediately after the system is started, the supply of heat to the carbon monoxide removal section is insufficient. There is a possibility that the temperature of the carbon monoxide removing portion becomes low and the carbon monoxide cannot be removed.

  Therefore, means for heating the carbon monoxide removal unit from the outside at the time of system startup has been proposed. For example, in Patent Document 1, the evaporation unit that evaporates water has a spiral shape and heat is taken away from an exhaust gas passage formed inside the evaporation unit, thereby evaporating the water. There is no mention of the issue of being cooled.

  Patent Document 2 describes a configuration in which the carbon monoxide removal unit is heated to a predetermined temperature by an electric heater unit provided outside the container, but the relationship with the evaporation unit provided inside the catalyst unit is as follows. Not mentioned.

JP 2008-19159 A JP 2005-15292 A

  In the evaporating section provided inside the carbon monoxide removing section, water flows downward spirally from above and exchanges heat with the exhaust gas in the exhaust path located inside thereof, so that the temperature gradually increases.

Since the carbon monoxide removal part is deprived of heat by this water, in addition to the temperature distribution that the upper temperature is low and the lower part is high, water flows along the bottom of the spiral path, so the spiral path A temperature distribution occurs when cooled along.

  However, with the thing of patent document 1, when the temperature of the carbon monoxide removal part is low at the time of starting, performance cannot fully be exhibited. Moreover, it is possible to suppress the temperature variation in the vertical direction of the carbon monoxide removal part due to the cooling action of water. I can't. Patent Document 2 also has a configuration in which a heater is provided outside to heat the catalyst, but it does not have a function of correcting temperature variations due to cooling of internal water by the heater.

  The present invention has been made in view of the above points, and hydrogen capable of stably removing carbon monoxide in the reformed gas by setting the carbon monoxide removal section at the time of startup to an optimum temperature distribution. An object of the present invention is to provide a manufacturing apparatus and a fuel cell power generation system.

In order to solve the above-described conventional problems, the hydrogen production apparatus of the present invention includes an inner cylinder and an outer cylinder that are arranged concentrically in a vertical axial direction , and a combustion cylinder that is arranged concentrically inside the inner cylinder. A partition cylinder that has a first cylinder part and a second cylinder part, and is arranged concentrically with the inner cylinder and the outer cylinder so as to partition the space between the inner cylinder and the outer cylinder inward and outward; is formed by filling a reforming catalyst between the inner cylinder and the second cylinder portion, a mixed gas of hydrocarbon fuel and water vapor is supplied, it generates a hydrogen-rich reformed gas by steam reforming reaction a reforming unit configured to, with the between the outer cylinder and the first cylindrical portion is formed by filling a carbon monoxide removal catalyst, the carbon monoxide removing unit that reduces carbon monoxide in the reformed gas, wherein It is formed inside the combustion cylinder, off consisting of the reformed gas discharged from the fuel cell without being consumed by the fuel cell Wherein the burner unit for heating the reformer by burning scan, is formed between the inner tube and the combustion tube, an exhaust gas passage through which a combustion exhaust gas generated in the burner portion, and the inner tube An evaporating section having a spiral passage formed between the first cylindrical portions, to which hydrocarbon fuel and water are supplied and generating the mixed gas by heat from the exhaust gas passage; and The carbon monoxide removal unit wound around the outer surface of the outer cylinder spirally through the carbon monoxide removal unit along the bottom surface and deprived of heat along the spiral passage by the water . to Yes and a heater for heating the low-temperature range.

With this configuration, the low temperature region of the carbon monoxide removal unit that has been deprived of heat by the water flowing through the spiral passage of the evaporation unit is spirally wound around the outer surface of the outer cylinder via the carbon monoxide removal unit. Since the heating is performed by the heater, the temperature variation in the carbon monoxide removing portion can be reduced, and the carbon monoxide in the reformed gas can be stably removed.

According to the present invention, the low temperature region of the carbon monoxide removal unit that has been deprived of heat by the water flowing through the spiral passage of the evaporation unit is spirally wound around the outer surface of the outer cylinder via the carbon monoxide removal unit. Since the heating is performed by the heater, the temperature variation in the carbon monoxide removing section can be reduced , and the carbon monoxide in the reformed gas can be stably removed.

Schematic sectional view showing a hydrogen production apparatus according to Embodiment 1 of the present invention. The fragmentary sectional view which shows the hydrogen production apparatus in Embodiment 1 of this invention, and shows the heat distribution between a heater, a carbon monoxide removal part, and an evaporation part

According to a first aspect of the present invention, there are provided an inner cylinder and an outer cylinder arranged concentrically in a vertical axial direction , a combustion cylinder arranged concentrically inside the inner cylinder, a first cylinder portion and a second cylinder portion. A partition cylinder arranged concentrically with the inner cylinder and the outer cylinder so as to partition the space between the inner cylinder and the outer cylinder inward and outward, and between the second cylinder portion and the inner cylinder is formed by filling a reforming catalyst, a mixed gas of hydrocarbon fuel and water vapor is supplied, and the reforming unit for generating hydrogen-rich reformed gas by steam reforming reaction, said first cylindrical portion A carbon monoxide removal catalyst is formed between the outer cylinders and is formed inside the combustion cylinder and consumed by the fuel cell. The carbon monoxide removal unit reduces the carbon monoxide in the reformed gas. by burning the off-gas consisting of the reformed gas discharged from the fuel cell to Sarezu burner unit for heating the reforming section Is formed between the inner cylinder and the combustion cylinder, and an exhaust gas passage through which a combustion exhaust gas generated in the burner portion, the helical path formed between the inner cylinder and the first cylindrical portion Having an evaporation section that is supplied with hydrocarbon fuel and water and generates the mixed gas by heat from the exhaust gas passage, and through the carbon monoxide removal section along the bottom surface of the passage. wound helically on the outer surface of the outer cylinder, is intended to have a a heater for heating the low-temperature range of the carbon monoxide removing unit which heat is removed along the helical path by the water, the A heater in which the low temperature region of the carbon monoxide removal unit, which has been deprived of heat by the water flowing through the spiral passage of the evaporation unit, is spirally wound around the outer surface of the outer cylinder via the carbon monoxide removal unit. The temperature variation in the carbon monoxide removal part is low because Can, carbon monoxide in the reformed gas can be stably removed.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a schematic cross-sectional view showing a hydrogen production apparatus according to Embodiment 1 of the present invention.

  In FIG. 1, a hydrogen production apparatus according to Embodiment 1 includes a reforming unit 1 that generates a hydrogen-rich reformed gas from a hydrocarbon-based fuel and water by a steam reforming reaction, and monoxide from the reformed gas. The carbon monoxide removing unit 2 for reducing carbon, the burner unit 3 for heating the reforming unit 1 by burning off-gas returned from the fuel cell 7 supplied with the reformed gas, and the combustion exhaust generated in the burner unit 3 An exhaust gas passage 6 through which gas passes, an evaporation portion 4 comprising a spiral passage for converting water into water vapor by heat from the exhaust gas passage 6, and a spiral heater 5 for heating the carbon monoxide removal portion, The exhaust gas passage 6, the evaporation portion 4, the carbon monoxide removal portion 2, and the heater 5 are arranged in a cylindrical shape in the order of the periphery around the portion 3, and the starting point of the spiral passage of the evaporation portion 4 and the spiral of the heater 5 Characterized by matching the starting pointAccording to this embodiment, it is possible to raise the temperature of the upper part of the carbon monoxide removal unit that is easily cooled by water.

  In addition, the spiral passage pitch 9 of the evaporator 4 and the spiral pitch 8 of the heater are arranged substantially the same. According to this embodiment, it is possible to reduce the temperature distribution by heating the place where the carbon monoxide removal unit is cooled along the spiral path with the heater provided at substantially the same pitch. is there.

  The starting point of the helical pitch 8 of the heater 5 is densely arranged. According to this embodiment, it is possible to reduce the temperature distribution by making the heat distribution generated above and below the carbon monoxide removing section pitch dense of the heater.

  Hereinafter, the present embodiment will be described in detail with reference to FIG.

  In FIG. 1, the hydrogen production apparatus 10 is formed as a whole by a double cylinder in which an axially vertical inner cylinder 11 and an outer cylinder 12 are arranged concentrically, and a combustion cylinder 13 is concentrically arranged inside the inner cylinder 11. Arranged and provided.

A combustion plate 14 is provided in the lower portion of the combustion cylinder 13 so as to partition the combustion cylinder 13 vertically. The center of the combustion plate 14 is formed as a combustion part 3 that is convexly bent upward, and a combustion nozzle 15 that penetrates from the upper side to the center part of the combustion part 3 and has a nozzle port at the tip is attached. The combustion unit 3 is formed with a plurality of combustion air supply ports 16 formed so as to penetrate vertically. A fuel gas supply pipe 17 is connected to the combustion nozzle 15 above the combustion section 3, and a combustion air supply pipe 19 connected to the blower fan 18 is inserted into the combustion cylinder 13 above the combustion section 3. The lower end of the combustion air supply pipe 19 is opened as an air discharge port. The combustion unit 3 having the combustion air supply port 16 and the combustion nozzle 15 form a heating means such as a burner. The fuel gas supplied from the fuel gas supply pipe 17 is ejected from the nozzle port at the lower end of the combustion nozzle 15 to the lower side of the combustion unit 3, and the air supplied from the blower fan 18 through the combustion air supply pipe 19 is discharged from the air. After being discharged from the outlet, it passes through the combustion air supply port 16 and is supplied to the lower part of the combustion part 3. This fuel gas and air are mixed and a flame is jetted downward from the combustion part 3. Combustion takes place. This combustion is performed so that a flame is generated in the entire lower surface recess of the convexly bent combustion section 3. An exhaust gas passage 6 is formed between the combustion cylinder 13 and the inner cylinder 11, and high-temperature exhaust gas generated by combustion in the combustion unit 3 of the heating means is exhausted from the opening at the lower end of the combustion cylinder 13. After passing through the passage 6, it is discharged.

On the other hand, the upper and lower portions between the inner cylinder 11 and the outer cylinder 12 are closed, and the closed space between the inner cylinder 11 and the outer cylinder 12 is divided into the inside and outside by a partition cylinder 20 concentric with these. is there.
The partition cylinder 20 has an upper portion formed as a small-diameter cylindrical portion 20a and a lower portion formed as a large-diameter cylindrical portion 20b. The reforming catalyst 1 is filled between the large-diameter cylindrical portion 20b and the inner cylinder 11 to form the reforming portion 1. It is. Further, a carbon monoxide removal part 2 is formed between the small diameter cylinder part 20a and the outer cylinder 12 by filling a carbon monoxide removal catalyst. In addition, the space between the inner cylinder 11 and the small diameter cylinder portion 20a is formed as the evaporation section 4, and the space between the large diameter cylinder section 20b and the outer cylinder 12 is formed as the transition flow path 21. Is.

  A raw material supply unit 22 and a water supply unit 23 are connected to the evaporation unit 4, and a hydrocarbon-based fuel such as city gas or LPG is mixed from the raw material supply unit 22 and water is mixed from the water supply unit 23. It is supplied to the evaporation unit 3. When the hydrocarbon fuel and water are supplied to the evaporation unit 3 in this way, a mixed gas of hydrocarbon fuel and water vapor is generated by heating with the high-temperature exhaust gas flowing through the exhaust gas passage 6. This mixed gas is supplied to the reforming unit 1, and a hydrocarbon-based fuel and water undergo a steam reforming reaction to generate a hydrogen-rich reformed gas. Since the steam reforming reaction is an endothermic reaction, the high-temperature exhaust gas generated by the combustion in the combustion unit 3 as described above is passed through the exhaust gas passage 6 and the reforming unit 1 is heated to about 600 to 700 ° C. The reforming reaction temperature is maintained.

  The reformed gas generated in the reforming unit 1 is supplied to the carbon monoxide removing unit 2 through the transfer channel 21, and the carbon monoxide in the reformed gas is removed. The reformed gas from which carbon monoxide has been removed in this manner is sent to the fuel cell 7. The fuel cell 7 is formed with an anode 24 and a cathode 25, and the reformed gas produced by the hydrogen production device 8 as described above is supplied to the anode 24. Thus, when the reformed gas is supplied to the anode 24, oxygen in the air supplied to the cathode 25 and hydrogen in the reformed gas undergo an electrochemical reaction to generate electric power.

  The reformed gas containing hydrogen that has not been consumed for power generation is discharged from the anode 24 of the fuel cell 7 as off-gas. The fuel gas supply pipe 4 is connected to the anode 24 and is discharged from the anode 24. The off-gas is returned to the hydrogen production apparatus 10 through the fuel gas supply pipe 26. The off gas is supplied to the combustion nozzle 15 through the fuel gas supply pipe 17 and burned in the combustion unit 3 using the off gas as the combustion gas. A hydrocarbon-based fuel is also supplied to the fuel gas supply pipe 26 from the raw material supply unit 22, and when the operation of the hydrogen production apparatus 10 is started up or when the amount of return of off-gas is insufficient, the hydrocarbon is supplied. The system fuel is burned with fuel gas.

In the present embodiment, the evaporation portion 3 by molding a SUS wire 28 spirally to form a the inner cylinder 11 a helical passage 27 nipping between the first cylindrical portion 20a. Further, the heater 5 is wound in close contact with the outer surface of the outer cylinder 12 in a spiral shape so as to sandwich the carbon monoxide removing portion 2, and the upper ends of the spirals of the SUS wire 28 and the heater 5 coincide with each other and the SUS wire 28 and the heater 5 are aligned. The spirals are also set at almost the same pitch.

FIG. 2 is a partial cross-sectional view showing the heat distribution among the heater, the carbon monoxide removal unit, and the evaporation unit. The temperature distribution in the low temperature region 31 from which heat has been removed in the vicinity of the upper end of the carbon monoxide removal unit 2 by water can be made uniform by the heating region 30 by the heater 5. Further, by making the spiral pitch of the SUS wire 28 and the heater 5 substantially the same, heat is supplied from the heater 5 to the low temperature region of the carbon monoxide removal unit 2 generated along the SUS wire 28, and the temperature distribution is made uniform. I can do it. Further, since the water on the upper surface of the SUS wire 28 is heated and evaporated from the exhaust gas passage 6, heat is hardly taken away below. Therefore, the spiral pitch 8 of the heater 5 also increases the winding watt density at the top.

  As described above, according to the present invention, by arranging the helical heaters at appropriate positions and pitches, the carbon monoxide removal unit at the time of startup has an optimal temperature distribution, and the carbon monoxide in the reformed gas is reduced. It can be removed stably and can be used for applications such as a fuel cell power generation system equipped with a hydrogen production apparatus.

DESCRIPTION OF SYMBOLS 1 Reforming part 2 Carbon monoxide removal part 3 Burner part 4 Evaporating part 5 Heater 6 Exhaust gas passage 7 Fuel cell

Claims (1)

An inner cylinder and an outer cylinder arranged in concentric circles with the axial direction being vertical;
A combustion cylinder disposed concentrically inside the inner cylinder;
A partition cylinder having a first cylinder part and a second cylinder part, and arranged concentrically with the inner cylinder and the outer cylinder so as to partition the space between the inner cylinder and the outer cylinder inward and outward;
Is formed by filling a reforming catalyst between the inner cylinder and the second cylinder portion, a mixed gas of hydrocarbon fuel and water vapor is supplied, it generates a hydrogen-rich reformed gas by steam reforming reaction A reforming section to perform,
A carbon monoxide removal portion that is formed by filling a carbon monoxide removal catalyst between the first tube portion and the outer tube, and that reduces carbon monoxide in the reformed gas ;
A burner portion that is formed inside the combustion cylinder and burns off- gas composed of the reformed gas discharged from the fuel cell without being consumed by the fuel cell to heat the reforming portion;
An exhaust gas passage formed between the combustion cylinder and the inner cylinder, through which combustion exhaust gas generated in the burner portion passes ,
An evaporation section having a spiral passage formed between the inner cylinder and the first cylinder section, to which hydrocarbon fuel and water are supplied and to generate the mixed gas by heat from the exhaust gas passage When,
The carbon monoxide wound spirally around the outer surface of the outer cylinder through the carbon monoxide removal portion along the bottom surface of the passage, and deprived of heat along the spiral passage by the water hydrogen production apparatus for chromatic and a heater for heating the low-temperature range of the removing unit.