JP7206121B2 - Fuel reformer unit - Google Patents

Description

The present invention relates to fuel reformer units.

A fuel cell system generates power by supplying a reformed gas produced by reforming fuel in a fuel reforming unit to a fuel cell stack. In the fuel reforming unit, each component including an evaporator and a reformer is configured separately. Therefore, it is necessary to take countermeasures against gas leaks at the connecting points of each component.

For example, in Patent Document 1 below, an evaporator and a reformer are accommodated in one case, and a gas flow path for raising the temperature of the fuel is provided in the case to simplify the configuration and reduce the size. A fuel reformer unit is disclosed.

Japanese Patent Application Laid-Open No. 2001-253704

However, the fuel reforming unit of Patent Document 1 has a structure in which heat is exchanged only from the outside of the reformer as a whole. may be uniform. This may reduce the reforming performance of the reformer.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a fuel reformer unit that can optimize the temperature distribution.

A fuel reforming unit of the present invention for achieving the above object comprises an evaporating section for evaporating fuel, a superheating section for superheating the vaporized fuel, and a reforming catalyst for reforming the superheated fuel. and a fuel reformer unit. The fuel reforming unit has a heat exchange section that supplies heat from heated gas to the evaporating section, the superheating section, and the reforming section, and a gas generating section that generates a reformed gas from the fuel. Further, in the fuel reforming unit, the evaporating section, the superheating section, and the reforming section are integrally formed, and the gas generating section and the heat exchanging section are arranged in layers facing each other, and the gas is The generating section is configured by a fuel flow path of the evaporating section, a fuel flow path of the superheating section, and a fuel flow path of the reforming section, and the heat exchange section includes a heating flow path of the evaporating section, A heating channel of the superheating section and a heating channel of the reforming section, and a fuel channel of the evaporating section, a fuel channel of the superheating section, and a fuel channel of the reforming section. , the heating channel of the evaporating section, the heating channel of the superheating section, and the heating channel of the reforming section are alternately stacked, and in the superheating section, the flow direction of the fuel of the gas generating section is opposite to the flow direction of the heating gas in the heat exchange section .

According to the present invention, the size of the fuel reforming unit can be reduced, the temperature distribution of the fuel reforming unit can be optimized, and the reforming performance of the reformer can be improved.

1 is a schematic configuration diagram showing a fuel reforming system; FIG. FIG. 3 is a configuration diagram for explaining a fuel reforming unit; FIG. 4 is a plan view showing the flow of fuel gas in the fuel reforming unit; FIG. 4 is a plan view showing the flow of heating gas in the fuel reforming unit; FIG. 3 is a side view showing a portion of the fuel reforming unit in cross section; FIG. 4 is a plan view schematically showing a fuel side plate of the fuel reforming unit; FIG. 4 is a plan view schematically showing a heating side plate of the fuel reforming unit; FIG. 8 is a plan view showing the flow of the fuel gas in the gas generation section and the heating gas in the heat exchange section of the fuel reforming unit according to Modification 1; FIG. 8 is a plan view schematically showing a fuel-side plate and a heating-side plate of a fuel reforming unit according to Modification 1; FIG. 10 is a plan view showing the flow of fuel gas in the gas generation section and heating gas in the heat exchange section of the fuel reforming unit according to Modification 2; FIG. 11 is a plan view schematically showing a fuel side plate and a heating side plate of a fuel reforming unit according to Modification 2; 10 is a plan view showing the flow of fuel gas in the gas generation section and heating gas in the heat exchange section of the fuel reforming unit according to Modification 3. FIG. FIG. 11 is a plan view schematically showing a fuel side plate and a heating side plate of a fuel reforming unit according to Modification 3; 14 is a plan view showing the flow of fuel gas in the gas generation section and heating gas in the heat exchange section of the fuel reforming unit according to Modification 4. FIG. FIG. 11 is a plan view schematically showing a fuel side plate and a heating side plate of a fuel reforming unit according to Modification 4; 14 is a plan view showing the flow of fuel gas in the gas generation section and heating gas in the heat exchange section of the fuel reforming unit according to Modification 5. FIG. FIG. 11 is a plan view schematically showing a fuel side plate and a heating side plate of a fuel reforming unit according to Modification 5;

Hereinafter, embodiments of the present invention will be described with reference to the attached drawings. Note that the following description does not limit the technical scope or the meaning of terms described in the claims. Also, the dimensional ratios in the drawings are exaggerated for convenience of explanation, and may differ from the actual ratios.

(Fuel cell system 10)
FIG. 1 is a schematic configuration diagram showing a fuel cell system 10. As shown in FIG. A fuel cell system 10 according to an embodiment of the present invention will be described with reference to FIG.

The fuel cell system 10 shown in FIG. 1 reforms fuel to generate a reformed gas RG, and supplies the reformed gas RG and the oxidant gas OG to the fuel cell stack 11 to generate power. The reformed gas RG is an anode gas supplied to the anode electrode of the fuel cell stack 11 . The oxidant gas OG is cathode gas supplied to the cathode electrode of the fuel cell stack 11 . The oxidant gas OG is composed of oxygen, oxygen-containing air, or the like.

The fuel cell stack 11 of this embodiment is applied to a solid oxide fuel cell (SOFC: Solid Oxide Fuel Cell). Since the SOFC can use not only hydrogen but also carbon monoxide and methane as the anode gas, the power generation efficiency of the fuel reforming unit 100 can be improved.

The fuel is not particularly limited as long as it can be reformed and used as anode gas for power generation in the fuel cell stack 11 . Fuels include, for example, methane (CH ₄ ), ethane (C ₂ H ₆ ), propane (C ₃ H ₈ ), butane (C ₄ H ₁₀ ), gasoline, naphtha, kerosene, light oil, natural gas, LPG, urban gas, methanol (CH ₃ OH), ethanol (C ₂ H ₅ OH), DME (CH ₃ OCH ₃ ), acetone (CH ₃ C(=O)CH ₃ ), biofuel and the like. In the present embodiment, a case where the reformed gas RG is generated using a liquid water-containing fuel MW obtained by mixing fuel and water will be described as an example.

Referring to FIG. 1, a fuel cell system 10 includes a fuel tank 20 storing water-containing fuel MW, a heater 31, a mixer 32, a combustor 33, an oxidant supply section 41, and a heat exchanger 42. , and a fuel reforming unit 100 .

The fuel tank 20 stores water-containing fuel MW, which is a mixture of fuel and water. By storing a mixture of fuel and water, it is not necessary to separately provide a fuel tank for storing fuel and a water storage tank for storing water. Thereby, the configuration of the fuel reforming unit 100 can be simplified and the size thereof can be reduced. The fuel tank 20 may be provided with a concentration sensor for detecting the composition of fuel and water.

The heater 31 heats the anode off-gas and cathode off-gas discharged from the fuel cell stack 11 . A mixer 32 mixes the heated anode off-gas and cathode off-gas. The combustor 33 combusts the mixed anode off-gas and cathode off-gas to generate high-temperature heating gas HG. The hot heated gas HG is supplied to the fuel reforming unit 100 and the heat exchanger 42 .

The oxidant supply unit 41 supplies an oxidant gas OG made of oxygen or air. The oxidant supply unit 41 of the present embodiment is composed of a blower that sucks air from the outside and supplies it to the heat exchanger 42 .

The heat exchanger 42 heats the oxidant gas OG by exchanging heat between the oxidant gas OG supplied from the oxidant supply unit 41 and the heating gas HG supplied from the combustor 33 . The fuel cell stack 11 applied to SOFC operates at a high temperature of about 500-1200.degree. Therefore, during startup and operation, the oxidant gas OG heated to a high temperature is circulated to raise the temperature of the fuel cell stack 11 or maintain the high temperature state of the fuel cell stack 11 .

The fuel reforming unit 100 includes an evaporator 110 that evaporates (vaporizes) a water-containing fuel MW (corresponding to "fuel") to generate a fuel gas FG containing water vapor, and a fuel gas FG (corresponding to "evaporated fuel"). ), and a reforming unit 130 that includes a reforming catalyst and reforms the superheated fuel gas FG.

The water-containing fuel MW in the fuel tank 20 is supplied to the fuel reforming unit 100, vaporized into fuel gas FG, and then reformed into reformed gas RG. The reformed gas RG is supplied to the fuel cell stack 11 as anode gas.

Evaporator 110 evaporates water-containing fuel MW supplied from fuel tank 20 to generate fuel gas FG containing water vapor and fuel.

The superheating section 120 has a function of superheating the fuel gas FG supplied to the reforming section 130 . The superheating temperature in the superheating section 120 is not particularly limited, but can be, for example, 500 degrees or higher.

The reforming section 130 has a rectangular shape. The lateral direction of the reforming section 130 is the vertical direction Z, and the longitudinal direction is the lateral direction X. As shown in FIG. The reforming section 130 has a reforming catalyst that accelerates the reforming reaction. The reforming catalyst is applied to a portion of the surface of the fuel side plate 101 corresponding to the reforming section 130 . The reformer 130 reforms the fuel gas FG supplied from the evaporator 110 to generate the reformed gas RG supplied to the fuel cell stack 11 . In the reforming section 130, the fuel gas and water vapor in the fuel gas FG undergo a catalytic reaction, and the reformed gas RG is generated by steam reforming.

The reforming unit 130 promotes the steam reforming reaction of the water-containing fuel MW as a fuel, so that the reformed gas RG is hydrogen (H ₂ ), carbon monoxide (CO), methane (C ₂ H ₄ ), for example. etc. The reformed gas RG is supplied to the fuel cell stack 11 and used as anode gas for power generation.

The oxidant gas OG supplied from the oxidant supply unit 41 is supplied to the heat exchanger 42, heated in the heat exchanger 42, and then supplied to the fuel cell stack 11 as cathode gas.

The anode off-gas and cathode off-gas discharged from the fuel cell stack 11 are heated by the heater 31, mixed by the mixer 32, and combusted by the combustor 33 to form the heating gas HG. The heated gas HG branches and flows to the heat exchanger 42 and the fuel reforming unit 100 .

The heated gas HG flowing into the heat exchanger 42 is discharged outside the heat exchanger 42 after heat-exchanging with the oxidant gas OG. Similarly, the heated gas HG that has flowed into the fuel reforming unit 100 exchanges heat with the fuel gas FG in the reforming section 130 , the superheating section 120 and the evaporating section 110 , and then is discharged to the outside of the fuel reforming unit 100 . The energy efficiency of the fuel reforming unit 100 can be improved by utilizing the heat quantity of the heating gas HG consisting of the anode off-gas and the cathode off-gas for heating the heat exchanger 42 and the fuel reforming unit 100 .

FIG. 2A is a configuration diagram for explaining the fuel reforming unit 100. FIG. FIG. 2B is a plan view showing the flow of the fuel gas FG in the fuel reforming unit 100. FIG. FIG. 2C is a plan view showing the flow of the heating gas HG in the fuel reforming unit 100. FIG.

Referring to FIG. 2A, fuel reforming unit 100 has a laminate 100S in which a plurality of fuel side plates 101 and a plurality of heating side plates 102 are alternately laminated. Each of fuel-side plate 101 and heating-side plate 102 has functions of evaporating section 110 , superheating section 120 and reforming section 130 . The fuel-side plate 101 and the heating-side plate 102 form a gas generator 100A that generates the reformed gas RG from the water-containing fuel MW (corresponding to fuel). The heating side plate 102 forms a heat exchange portion 100B with the fuel side plate 101 .

Referring to FIG. 2B, the gas generator 100A is configured by fuel passages 111, 121, and 131 through which the water-containing fuel MW and the fuel gas FG flow. The fuel passages 111 , 121 , 131 are formed on the surface of the fuel side plate 101 . In the fuel side plate 101, the fuel gas FG flows through the fuel passage 111 of the evaporating section 110, the fuel passage 121 of the superheating section 120, and the fuel passage 131 of the reforming section 130 in this order. In the gas generating section 100A, the evaporating section 110 is located at the most upstream position.

The water-containing fuel MW is vaporized in the evaporator 110 to become a fuel gas FG containing water vapor. Fuel gas FG is supplied to reforming section 130 after being heated to a temperature suitable for reaction in superheating section 120 . The reforming section 130 generates a hydrogen-rich reformed gas RG from the fuel gas FG by steam reforming.

Referring to FIG. 2C, heat exchange section 100B is configured by heating channels 112, 122, and 132 through which heating gas HG flows. The heating channels 112 , 122 , 132 are formed on the surface of the heating-side plate 102 . In the heating-side plate 102 , the heating gas HG passes through the heating channel 122 of the superheating section 120 and then flows through the heating channel 112 of the evaporating section 110 and the heating channel 132 of the reforming section 130 . Heated gas HG heats evaporating section 110 and reforming section 130 after heat exchange in superheating section 120 . Therefore, the temperature of superheating section 120 is higher than that of evaporating section 110 and reforming section 130 .

In other words, the fuel reforming unit 100 has a structure in which the fuel channels 111, 121, 131 and the heating channels 112, 122, 132 are alternately stacked. By alternately stacking the fuel channels 111, 121, 131 and the heating channels 112, 122, 132, the temperature unevenness in the stacking direction of the stack 100S can be reduced, and the temperature distribution can be optimized. .

FIG. 3A is a side view showing a portion of the fuel reforming unit 100 in cross section. 3B is a plan view schematically showing the fuel side plate 101 of the fuel reforming unit 100. FIG. 3C is a plan view schematically showing the heating side plate 102 of the fuel reforming unit 100. FIG.

As shown in FIG. 3A, the fuel reforming unit 100 includes a water-containing fuel MW supply port 101a, a reformed gas RG discharge port 101b, a heating gas HG supply port 102a, and a heating gas HG discharge port 102b. and

As shown in FIG. 3B , the fuel side plate 101 has fuel passages 111 , 121 , 131 . The fuel channel 111 of the evaporating section 110 and the fuel channel 121 of the superheating section 120 are dot-shaped channels formed by arranging a plurality of protrusions 101A on the surface of the fuel side plate 101 . The flow of the fuel gas FG flowing through the fuel passages 111 and 121 formed between the plurality of convex portions 101A meanders, and the flow direction includes a plurality of (two or more) directions. As a result, the diffusibility of the fuel gas FG is improved, and the effective heat exchange area with the heat exchange section 100B side is increased. As a result, the inlet temperature of the reforming section 130 can be increased and the concentration of the fuel gas FG can be made uniform.

The fuel channel 131 of the reforming section 130 is a straight channel formed by arranging a plurality of ribs 101B linearly extending along the vertical direction Z on the surface of the fuel side plate 101 . The fuel passage 131 formed between the plurality of ribs 101B forms a flow that unidirectionally circulates the fuel gas FG along the vertical direction Z from above to below. In other words, in the gas generation section 100A, the direction of flow of the fuel gas FG is the lateral direction (Z direction) of the reforming section 130 . A reforming catalyst is applied to the surface of the fuel channel 131 of the reforming section 130 .

In the present embodiment, the reforming section 130 has a structure provided with a fuel flow path 131 coated with a reforming catalyst formed separately from the fuel side plate 101, and the structure is formed on the surface of the fuel side plate 101. Formed by placing. The structure can be mass-produced by applying a reforming catalyst to a long substrate by roll-to-roll and then cutting the substrate.

The straight flow path of the fuel flow path 131 of the reforming section 130 of the gas generating section 100A is configured to have a smaller total cross-sectional area than the dot-shaped flow path of the fuel flow path 121 of the superheating section 120. ing. As a result, the pressure loss in the fuel flow path 131 of the reforming section 130 becomes greater than the pressure loss in the fuel flow path 121 of the superheating section 120 . In the gas generation section 100A, the fuel gas FG stays in the superheating section 120 for a longer time, so that the temperature rise and mixing effect of the fuel gas FG in the superheating section 120 can be enhanced.

Also, the evaporating section 110 and the reforming section 130 are arranged in parallel in the horizontal direction X. As shown in FIG. The superheating section 120 is arranged above the evaporating section 110 in the vertical direction Z. As shown in FIG. When the water-containing fuel MW, which is a liquid fuel, evaporates, it rises as gaseous fuel gas FG. Arranging the superheating section 120 above the evaporating section 110 in the vertical direction Z makes it easier to form the flow of the fuel gas FG from the evaporating section 110 to the superheating section 120 .

As shown in FIG. 3C , the heating-side plate 102 has heating channels 112 , 122 , 132 . The heating channel 112 of the evaporating section 110 and the fuel channel 131 of the reforming section 130 are straight channels formed by arranging a plurality of ribs 102A extending linearly along the vertical direction Z. be. The heating channel 122 of the heating part 120 is formed in a portion of the heating-side plate 102 where the plurality of ribs 102A of the heating channels 112 and 132 are not arranged.

Width W1 of evaporating section 110 is smaller than width W2 of reforming section 130 . Therefore, the total channel cross-sectional area of the heating channel 112 of the evaporating section 110 is smaller than the total channel cross-sectional area of the heating channel 132 of the reforming section 130 . Therefore, the pressure loss in the heating channel 112 of the evaporating section 110 is configured to be greater than the pressure loss in the heating channel 132 of the reforming section 130 . This makes it easier for the heating gas HG to flow toward the reforming section 130 than to the evaporating section 110 , and the temperature of the reforming section 130 is higher than that of the evaporating section 110 . As a result, a high conversion rate of the fuel gas FG can be maintained in the reforming section 130, so deterioration due to carbon deposition can be suppressed.

The fuel-side plate 101 and the heating-side plate 102 are made of, for example, metal plates such as stainless steel. The fuel channels 111, 121, 131 and the heating channels 112, 122, 132 can be formed by etching or pressing the surface of the metal plate. In this manner, the evaporating portion 110, the heating portion 120, and the reforming portion 130 can be simultaneously formed on the metal plate by etching or press working, so that the manufacturing process can be simplified.

Further, the design of the fuel channels 111, 121, 131 and the heating channels 112, 122, 132 can be determined according to the respective functions of the evaporating section 110, the superheating section 120, and the reforming section . Therefore, it can contribute to the optimization of the temperature distribution and the improvement of the reactivity of the reforming catalyst.

Moreover, by stacking the gas generation section 100A and the heat exchange section 100B, heat can be exchanged on a plane, so that the temperature distribution of the gas generation section 100A can be optimized.

2B and 2C, in evaporating section 110 and superheating section 120, the flow direction of fuel gas FG in fuel flow paths 111 and 121 and the flow direction of heating gas HG in heating flow paths 112 and 122 are as follows: It is the opposite direction. Thereby, in the evaporating section 110 and the superheating section 120, the downstream side of the flow of the fuel gas FG can be made higher than the upstream side. As a result, the temperature of the superheating section 120 is higher than that of the evaporating section 110, so that the fuel gas FG vaporized in the evaporating section 210 can be heated to a temperature suitable for reaction. Thereby, the reforming reaction of the fuel gas FG can be promoted. Further, in the reforming section 130, the flow direction of the fuel gas FG in the fuel channel 131 and the flow direction of the heating gas HG in the heating channel 132 are the same.

When the components of the evaporating section, the superheating section and the reforming section are configured separately, it is necessary to newly provide external piping and connecting parts to connect them. In this case, there is a risk of an increase in the number of parts and a complication of the structure in order to prevent gas leakage due to an increase in the number of connecting points. As a result, effective use of space cannot be achieved, the size of the fuel reforming unit may increase, and the manufacturing cost of the fuel reforming unit may increase.

On the other hand, according to the fuel reforming unit 100 according to the present embodiment, by integrally forming the evaporating section 110, the superheating section 120 and the reforming section 130, there is no need for external pipes or connecting parts that connect them. Therefore, the number of parts can be reduced and the structure can be simplified. As a result, the size of the fuel reforming unit 100 can be reduced.

In addition, in the case of a structure in which heat is exchanged only from the outside of the entire reformer, a temperature difference occurs between the outer peripheral portion and the central portion of the reformer, resulting in non-uniform reaction. As a result, the reforming performance may deteriorate.

On the other hand, according to the fuel reforming unit 100 according to the present embodiment, since the gas generation section 100A and the heat exchange section 100B are arranged alternately, it becomes easier to control the temperature of the gas generation section 100A. Thereby, the temperature distribution of the gas generation section 100A can be optimized. In particular, since the temperature of the reforming section 130 can be made uniform, the reforming performance can be improved.

As described above, the fuel reforming unit 100 of the present embodiment includes the evaporator 110 that evaporates the water-containing fuel MW (fuel) to generate the fuel gas FG, and the fuel gas FG (evaporated fuel) that is superheated. It is a fuel reforming unit comprising a superheating section 120 and a reforming section 130 which reforms the superheated fuel gas FG (fuel) provided with a reforming catalyst. The fuel reforming unit 100 includes a heat exchange section 100B that supplies heat from a heated gas HG to an evaporating section 110, a superheating section 120, and a reforming section 130, and a gas that generates a reformed gas RG from a fuel gas FG (fuel). and a generation unit 100A. The fuel reforming unit 100 is characterized in that the evaporating section 110, the superheating section 120 and the reforming section 130 are integrally formed, and the gas generating section 100A and the heat exchanging section 100B are arranged in layers facing each other. .

According to the fuel reforming unit 100, by integrally forming the evaporating section 110, the superheating section 120, and the reforming section 130, it is possible to reduce the number of pipes and manifolds for connecting each component. The space of the reforming unit 100 can be effectively used. Moreover, by stacking the gas generating section 100A and the heat exchanging section 100B so as to face each other, it is possible to reduce temperature unevenness in the stacking direction. As a result, the size of the fuel reforming unit 100 can be reduced, the temperature distribution of the fuel reforming unit 100 can be optimized, and the reforming performance of the reformer 130 can be improved.

Also, the superheating section 120 is arranged above the evaporating section 110 in the vertical direction Z. As shown in FIG. In the evaporation section 110 of the gas generation section 100A, the liquid water-containing fuel MW is evaporated and rises as the fuel gas FG. Therefore, by disposing the superheating section 120 above the evaporating section 110 in the vertical direction Z, the diffusibility of the fuel gas FG from the evaporating section 110 to the superheating section 120 can be enhanced.

In addition, in the superheating section 120, the flow direction of the fuel gas FG in the gas generation section 200A is opposite to the flow direction of the heating gas HG in the heat exchange section 200B. As a result, the inlet temperature of the reforming section 230 located on the upstream side of the flow of the heating gas HG of the superheating section 220 can be made higher than that of the evaporating section 110 located on the downstream side, thereby promoting the reforming reaction. As a result, a high fuel conversion rate can be maintained in the reforming section 230, so deterioration due to carbon deposition can be suppressed.

Further, in the gas generation section 100</b>A, the pressure loss in the fuel flow path 131 of the reforming section 130 is configured to be greater than the pressure loss in the fuel flow path 121 of the superheating section 120 . In the gas generation section 100A, by making the pressure loss of the reforming section 130 larger than the pressure loss of the superheating section 120, the temperature rise and the mixing effect in the superheating section 120 can be enhanced. As a result, a high conversion rate of the fuel gas FG can be maintained in the reforming section 130, so deterioration due to carbon deposition can be suppressed.

Moreover, the reforming portion 130 has a rectangular shape. In the gas generation section 100A, the direction of flow of the fuel gas FG is the lateral direction (Z direction) of the reforming section 130 . As a result, the length of the fuel passage 131 of the reforming section 130 is shortened. When the fuel gas FG of the same volume is circulated through the reforming section 130, the linear velocity of the fuel gas FG becomes smaller as the length of the fuel passage 131 becomes shorter. Therefore, since the flow velocity of the fuel gas FG in the reforming section 130 can be reduced, the utilization rate of the reforming catalyst on the surface of the reforming section 130 can be improved. As a result, a high conversion rate of the fuel gas FG can be maintained in the reforming section 130, so deterioration due to carbon deposition can be suppressed.

Further, in the heating channels 112 and 132 of the heat exchange section 100B, the pressure loss of the heating channel 112 of the evaporating section 110 is greater than the pressure loss of the heating channel 132 of the reforming section 130 . This makes it easier for the heating gas HG to flow toward the reforming section 130 than to the evaporating section 110 , and the temperature of the reforming section 130 is higher than that of the evaporating section 110 . As a result, a high conversion rate of the fuel gas FG can be maintained in the reforming section 130, so deterioration due to carbon deposition can be suppressed.

Further, in the gas generating section 100A, the flow direction of the fuel gas FG in the evaporating section 110 includes a plurality of directions. As a result, the diffusibility of the fuel gas FG is improved, and the effective heat exchange area with the heat exchange section 100B side is increased. As a result, the inlet temperature of the reforming section 130 can be increased and the concentration of the fuel gas FG can be made uniform. As a result, a high conversion rate of the fuel gas FG can be maintained in the reforming section 130, so deterioration of reforming performance due to carbon deposition can be suppressed.

Modifications of the fuel reforming unit will now be described with reference to FIGS. 4A to 8B.

(Modification 1)
4A is a plan view showing the flow of the fuel gas FG in the gas generation section 200A and the heating gas HG in the heat exchange section 200B of the fuel reforming unit according to Modification 1. FIG. 4B is a plan view schematically showing the fuel side plate 201 and the heating side plate 202 of the fuel reforming unit according to Modification 1. FIG.

In the fuel reforming unit according to Modification 1, all the flow directions of the fuel gas FG in the gas generation section 200A are opposite to (oppose to) the flow directions of the heating gas HG in the heat exchange section 200B. Different from the embodiment.

Referring to FIG. 4A, fuel gas FG of gas generating section 200A flows through evaporating section 210, superheating section 220 and reforming section 230 in this order. On the other hand, the heated gas HG of the heat exchange section 200B flows through the reforming section 230, the superheating section 220, and the evaporating section 210 in this order. As a result, the temperature of the fuel reforming unit increases in the order of the evaporating section 210, the superheating section 220, and the reforming section 230. FIG. By setting the reforming section 230 to the highest temperature, a high conversion rate of the fuel gas FG can be maintained in the reforming section 130 . In addition, since the superheating section 220 can be heated to a higher temperature than the evaporating section 210, the fuel gas FG vaporized in the evaporating section 210 can be heated to a temperature suitable for reaction. Thereby, the reforming reaction of the fuel gas FG can be promoted.

4B, the fuel side plate 201 has fuel passages 211, 221, 231. As shown in FIG. The fuel channel 211 of the evaporating section 210 and the fuel channel 231 of the reforming section 230 are formed by arranging a plurality of ribs 201A linearly extending along the vertical direction Z on the surface of the fuel side plate 201. It is a straight-shaped flow path. The fuel passage 211 formed between the plurality of ribs 201A forms a flow that allows the fuel gas FG to circulate in one direction along the vertical direction Z. As shown in FIG. The fuel passage 231 forms a flow that unidirectionally circulates the fuel gas FG along the vertical direction Z from above to below. The fuel passage 221 of the superheating portion 220 is formed in a portion of the fuel side plate 201 where the plurality of ribs 201A of the fuel passages 211 and 231 are not arranged.

4B, the heating-side plate 202 has heating channels 212, 222, and 232. As shown in FIG. The heating channel 212 of the evaporating section 210 and the heating channel 232 of the reforming section 230 are formed by arranging a plurality of ribs 202A linearly extending along the vertical direction Z on the surface of the heating side plate 202. It is a straight-shaped flow path. The heating channels 212 formed between the plurality of ribs 202A flow in one direction from top to bottom along the vertical direction Z, and the heating channels 232 flow in one direction from bottom to top along the vertical direction Z. flow. The heating channel 222 of the heating part 220 is formed in a portion of the heating side plate 202 where the plurality of ribs 202A of the heating channels 212 and 232 are not arranged.

As described above, in the fuel reforming unit according to Modification 1, all the flow directions of the fuel gas FG in the gas generation section 200A are opposite to the flow directions of the heating gas HG in the heat exchange section 200B. As a result, the temperature of the fuel reforming unit increases in the order of the evaporating section 210, the superheating section 220, and the reforming section 230, thereby further promoting the reforming reaction.

(Modification 2)
FIG. 5A is a plan view showing the flow of the fuel gas FG in the gas generation section 300A and the heating gas HG in the heat exchange section 300B of the fuel reforming unit according to Modification 2. FIG. 5B is a plan view schematically showing the fuel side plate 301 and the heating side plate 302 of the fuel reforming unit according to Modification 2. FIG.

The fuel reforming unit according to Modification 2 differs from the embodiment described above in that the evaporating section 310, the superheating section 320, and the reforming section 330 are vertically arranged in this order from below in the vertical direction Z. FIG.

Referring to the left diagram of FIG. 5A, the fuel gas FG of the gas generating section 300A flows upward along the vertical direction Z through the evaporating section 310, the superheating section 320, and the reforming section 330 in this order. Since the gaseous fuel gas FG rises, it is possible to easily form an upward flow along the vertical direction Z in the order of the evaporating section 310, the superheating section 320, and the reforming section 330. FIG.

With reference to the right diagram of FIG. 5A, the heated gas HG in the heat exchange section 300B flows downward along the vertical direction Z through the reforming section 330, the superheating section 320, and the evaporating section 310 in that order. That is, all flow directions of the heated gas HG in the heat exchange section 300B are opposite to the flow direction of the fuel gas FG in the gas generation section 300A. Since the heat exchange section 300B exchanges heat in the order of the reforming section 330, the superheating section 320, and the evaporating section 310, the temperature gradually decreases from the reforming section 330 on the upstream side to the evaporating section 310 on the downstream side. By setting the reforming section 330 to the highest temperature, a high conversion rate of the fuel gas FG can be maintained in the reforming section 330 . Further, by making the temperature of the superheating section 320 higher than that of the evaporating section 310, the fuel gas FG vaporized in the evaporating section 310 can be heated to a temperature suitable for reaction. Thereby, the reforming reaction of the fuel gas FG can be promoted.

5B, the fuel side plate 301 has fuel passages 311, 321, 331 that flow upward along the vertical direction Z. As shown in FIG. The fuel channel 311 of the evaporating section 310 and the fuel channel 321 of the superheating section 320 are dot-shaped channels formed by arranging a plurality of protrusions 301A on the surface of the fuel side plate 301 . The fuel channel 331 of the reforming section 330 is a straight channel formed by arranging a plurality of ribs 301B linearly extending along the vertical direction Z on the surface of the fuel side plate 301 .

5B, the heating-side plate 302 has heating channels 312, 322, 332 that flow downward along the vertical direction Z. As shown in FIG. The heating channels 312, 322, and 332 are straight channels formed by arranging a plurality of ribs 302A linearly extending along the vertical direction Z. As shown in FIG. Thereby, the heating channel 312 of the evaporating section 310, the heating channel 322 of the superheating section 320, and the heating channel 332 of the reforming section 330 are formed continuously with each other. By continuously forming the heating passages 312, 322, and 332, the flow of the heating gas HG can be made smooth, so that the efficiency of heat exchange by the heat exchange section 300B can be improved.

(Modification 3)
6A is a plan view showing the flow of the fuel gas FG in the gas generation section 400A and the heating gas HG in the heat exchange section 400B of the fuel reforming unit according to Modification 3. FIG. 6B is a plan view schematically showing the fuel side plate 401 and the heating side plate 402 of the fuel reforming unit according to Modification 3. FIG.

The fuel side plate 401 and the heating side plate 402 of the fuel reforming unit according to Modification 3 have a smaller aspect ratio (length in the Z direction/length in the X direction) than in Modification 2. FIG. Other configurations are the same as those of the second modification.

6A, the fuel gas FG of the gas generating section 400A flows upward along the vertical direction Z through the evaporating section 410, the superheating section 420, and the reforming section 430 in this order. 6A, the heating gas HG in the heat exchange section 400B flows downward along the vertical direction Z through the reforming section 430, the superheating section 420, and the evaporating section 410 in that order.

6B, the fuel side plate 401 has fuel passages 411, 421, 431 that flow upward along the vertical direction Z. As shown in FIG. The fuel channel 411 of the evaporating section 410 and the fuel channel 421 of the superheating section 420 are dot-shaped channels formed by arranging a plurality of protrusions 401A on the surface of the fuel side plate 401 . The fuel channel 431 of the reforming section 430 is a straight channel formed by arranging a plurality of ribs 401B linearly extending along the vertical direction Z on the surface of the fuel side plate 401 .

6B, the heating-side plate 402 has heating channels 412, 422, 432 flowing downward along the vertical direction Z. As shown in FIG. The heating channel 412 of the evaporating section 410, the heating channel 422 of the superheating section 420, and the heating channel 432 of the reforming section 430 are formed continuously with each other and extend linearly along the vertical direction Z. It is a straight flow path formed by arranging a plurality of ribs 402A that are aligned with each other.

As described above, the fuel side plate 401 and the heating side plate 402 of the fuel reforming unit according to the third modification have a smaller aspect ratio (length in the Z direction/length in the X direction) than in the second modification. As a result, the lengths of the fuel flow paths 411, 421, 431 are shortened. When the fuel gas FG of the same volume is circulated, the linear velocity of the fuel gas FG becomes smaller as the length of the fuel passages 411, 421, and 431 is shorter. As a result, since the flow velocity of the fuel gas FG in the gas generation section 400A can be reduced, the heat exchange in the heat exchange section 400B can be efficiently performed, and the catalyst utilization rate of the surface of the reforming section 430 can be improved. can.

(Modification 4)
FIG. 7A is a plan view showing the flow of the fuel gas FG in the gas generation section 500A and the heating gas HG in the heat exchange section 500B of the fuel reforming unit according to Modification 4. FIG. FIG. 7B is a plan view schematically showing the fuel side plate 501 and the heating side plate 502 of the fuel reforming unit according to Modification 4. FIG.

The fuel reforming unit according to Modification 4 differs from the embodiment described above in that the evaporating section 510, the superheating section 520, and the reforming section 530 are all arranged in parallel in the lateral direction X. FIG.

7A, the fuel gas FG in the gas generating section 500A rises from below to above along the vertical direction Z in the evaporating section 510 and then moves in the lateral direction (X direction) to reach the superheating section 520. flow into. After descending from top to bottom along the vertical direction Z in the superheating section 520, it moves in the lateral direction (X direction), flows into the reforming section 530, and rises from bottom to top along the vertical direction Z.

7A, the heated gas HG in the heat exchange section 500B moves downward along the vertical direction Z in the reforming section 530, moves in the lateral direction (X direction), and reaches the superheating section 520. flow into. After rising from bottom to top along the vertical direction Z in the superheating section 520, it moves in the horizontal direction (X direction), flows into the evaporating section 510, and descends along the vertical direction Z from top to bottom.

Thus, the flow direction of the fuel gas FG in the gas generation section 500A is opposite to the flow direction of the heating gas HG in the heat exchange section 500B. As a result, the inlet temperature of the reforming section 530 can be made higher than that of the superheating section 520 and the evaporating section 510, thereby promoting the reforming reaction.

7B, the fuel side plate 501 has fuel passages 511, 521, 531. As shown in FIG. The fuel channel 511 of the evaporating portion 510 and the fuel channel 521 of the superheating portion 520 are dot-shaped channels formed by arranging a plurality of convex portions 501A on the surface of the fuel side plate 501 . The fuel channel 531 of the reforming section 530 is a straight channel formed by arranging a plurality of ribs 501B linearly extending along the vertical direction Z on the surface of the fuel side plate 501 .

7B, the heating channel 512 of the evaporating section 510, the heating channel 522 of the superheating section 520, and the heating channel 532 of the reforming section 530 are arranged linearly along the vertical direction Z. It is a straight channel formed by arranging a plurality of extending ribs 502A.

As described above, in the fuel reforming unit according to Modification 4, the evaporating section 510, the superheating section 520, and the reforming section 530 are all arranged in parallel in the horizontal direction X. Therefore, the height of the fuel reforming unit in the vertical direction Z can be made relatively small. As a result, a space in the vertical direction Z can be secured when mounting the fuel reforming unit.

(Modification 5)
8A is a plan view showing the flow of the fuel gas FG in the gas generation section 600A and the heating gas HG in the heat exchange section 600B of the fuel reforming unit according to Modification 5. FIG. 8B is a plan view schematically showing the fuel side plate 601 and the heating side plate 602 of the fuel reforming unit according to Modification 5. FIG.

The fuel reforming unit according to Modification 5 differs from the above-described embodiment in that the superheating section 620 and the reforming section 630 are arranged in parallel in the lateral direction X. FIG. As in the above-described embodiments, the superheating section 620 is arranged above the evaporating section 610 in the vertical direction Z. As shown in FIG.

Referring to the left diagram of FIG. 8A, the fuel gas FG of the gas generating section 600A rises from below to above along the vertical direction Z in the evaporating section 610 and the superheating section 620, and then moves in the lateral direction (X direction). Then, it flows into the reforming section 630 and descends along the vertical direction Z from above.

Referring to the right diagram of FIG. 8A, heated gas HG in heat exchange section 600B flows into superheating section 620 and reforming section 630, and then descends downward along vertical direction Z from above. The heated gas HG descending from the superheating section 620 flows into the evaporating section 610 .

The flow direction of the fuel gas FG in the fuel passages 611 and 621 of the evaporating portion 610 and the superheating portion 620 of the gas generating portion 600A is the same as that of the heating passages 612 and 622 of the evaporating portion 610 and the superheating portion 620 of the heat exchanging portion 600B. It is the opposite direction to the flow direction of the heating gas HG. As a result, the temperature of the superheating section 620 can be made higher than that of the evaporating section 610, so that the heating gas HG vaporized in the evaporating section 610 can be superheated in the superheating section 620 to a temperature suitable for the reaction.

8B, fuel side plate 601 has fuel passages 611, 621, 631. Referring to FIG. The fuel channel 611 of the evaporating section 610 and the fuel channel 621 of the superheating section 620 are dot-shaped channels formed by arranging a plurality of protrusions 601A on the surface of the fuel side plate 601 . The fuel channel 631 of the reforming section 630 is a straight channel formed by arranging a plurality of ribs 601B linearly extending along the vertical direction Z on the surface of the fuel side plate 601 .

8B, the heating-side plate 602 has heating channels 612, 622, and 632. As shown in FIG. The heating channel 612 of the evaporating section 610, the heating channel 622 of the superheating section 620, and the heating channel 632 of the reforming section 630 have a plurality of ribs 602A extending linearly along the vertical direction Z. It is a straight flow path formed by

Although the fuel reforming unit according to the present invention has been described above through the embodiments and modifications, the present invention is not limited to the contents described in the embodiments and modifications, and is based on the description of the claims. can be changed as appropriate.

For example, the fuel-side plate and the heating-side plate of the fuel reforming unit are not limited to the structure in which they are alternately stacked one by one. may be combined and laminated. Further, the heating side plate may be arranged so as to sandwich the fuel side plate only in the outermost layer of the laminate of the fuel side plate and the heating side plate, or the heating side plate may be arranged only on one side of the fuel side plate. good too.

Further, the shapes of the flow paths forming the evaporating section, the superheating section, and the reforming section are not limited to the configurations of the above-described embodiments and modifications, and can be changed as appropriate. For example, the heating section may be formed by a straight channel.

Further, the fuel side plate and the heating side plate are not limited to the configuration of separate plates, and may be configured from one plate. In this case, the fuel channel can be formed on one surface of one plate, and the heating channel can be formed on the other surface.

Also, the fuel reforming unit may be configured by appropriately combining the specifications of the above-described embodiment and modifications.

Further, in the above-described embodiment, the fuel cell stack is applied to a solid oxide fuel cell (SOFC), but is not limited to this. Electrolyte Membrane Fuel Cell), Phosphoric Acid Fuel Cell (PAFC) or Molten Carbonate Fuel Cell (MCFC).

10 fuel cell system,
11 fuel cell stack,
20 fuel tank,
31 heater,
32 mixers,
33 combustor;
41 oxidant supply unit,
42 heat exchangers,
100 fuel reformer unit,
100A, 200A, 300A, 400A, 500A, 600A gas generator,
100B, 200B, 300B, 400B, 500B, 600B heat exchange section,
100S laminate,
101, 201, 301, 401, 501, 601 fuel side plate,
101a supply port,
101b outlet,
102, 202, 302, 402, 502, 602 heating side plate,
102a supply port,
102b outlet,
110, 210, 310, 410, 510, 610 evaporator,
111, 211, 311, 411, 511, 611 fuel channel,
112, 212, 312, 412, 512, 612 heating channel,
120, 220, 320, 420, 520, 620 heating unit,
121, 221, 321, 421, 521, 621 fuel channel,
122, 222, 322, 422, 522, 622 heating channel,
130, 230, 330, 430, 530, 630 reforming section,
131, 231, 331, 431, 531, 631 fuel channel,
132, 232, 332, 432, 532, 632 heating channel,
FG fuel gas,
HG heating gas;
MW water-containing fuel (fuel),
OG oxidant gas,
RG reformed gas,
Z vertical direction.

Claims (6)

an evaporator that evaporates fuel;
a superheating unit for superheating the vaporized fuel;
a reformer for reforming the superheated fuel, the reformer comprising a reforming catalyst,
a heat exchange section that supplies heat from a heated gas to the evaporating section, the superheating section, and the reforming section;
a gas generator that generates a reformed gas from the fuel,
The evaporating section, the superheating section and the reforming section are integrally formed, and
The gas generation unit and the heat exchange unit are arranged in layers facing each other ,
The gas generating section is configured by a fuel flow path of the evaporating section, a fuel flow path of the superheating section, and a fuel flow path of the reforming section,
The heat exchange section is composed of a heating flow path of the evaporating section, a heating flow path of the superheating section, and a heating flow path of the reforming section,
The fuel flow path of the evaporating section, the fuel flow path of the superheating section, the fuel flow path of the reforming section, the heating flow path of the evaporating section, the heating flow path of the superheating section, and the reforming section The heating channels of the part are alternately laminated,
The fuel reforming unit , wherein in the superheating section, the flow direction of the fuel in the gas generating section is opposite to the flow direction of the heating gas in the heat exchanging section . 2. The fuel reforming unit according to claim 1, wherein the superheating section is arranged vertically above the evaporating section. 3. The fuel reforming unit according to claim 1, wherein the pressure loss in the reforming section is greater than the pressure loss in the superheating section in the flow path of the fuel of the gas generating section. The modified section has a rectangular shape,
The fuel reforming unit according to any one of claims 1 to 3 , wherein in the gas generating section, the direction of flow of the fuel is the lateral direction of the reforming section. 5. The fuel reforming unit according to any one of claims 1 to 4 , wherein the pressure loss in the evaporating section is greater than the pressure loss in the reforming section in the flow path of the heating gas of the heat exchange section. The fuel reforming unit according to any one of claims 1 to 5 , wherein in the gas generation section, the fuel flow direction of the evaporator section includes a plurality of directions.

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