JP2000344503A - Fuel reforming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact fuel reformer with the height controlled to be low. SOLUTION: In the fuel reforming device for generating a hydrogen enriched reformed gas from an alcohol, dimethyl ether or a hydrocarbon based fuel, a reforming part 8 where an endothermic reaction occurs, and catalytic combustion parts 7, 9 where an exothermic reaction occur, are formed into rectangular flat plate elements and the flat plate elements of the reforming part and the catalytic combustion parts are brought into close contact with each other horizontally so that the major side is made horizontal and the minor side is made vertical and are laminated to form a flat plate element laminated body and a manifold for air and the combustion gas along one of the minor side of the flat plate element and a manifold for the reformed gas and an off-gas along another minor side are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is used, for example, for producing hydrogen necessary for a portable fuel cell for a general power supply or a fuel cell mounted on an electric vehicle. Also, the present invention relates to a fuel reformer for converting a hydrocarbon material such as natural gas into a hydrogen-rich reformed gas.

[0002]

2. Description of the Related Art As a conventional technique for producing a hydrogen-rich gas from an alcohol raw material such as methanol, dimethyl ether, or a hydrocarbon raw material such as natural gas as a primary fuel, there is known a plate-stacked structure disclosed in Japanese Patent Application No. 9-45898. Fuel reformer. FIG. 9 is a configuration diagram showing a basic configuration of such a fuel reforming apparatus having a flat plate lamination structure. In the figure, 31 is a liquid raw material heating section, 32 is an evaporating section, 33 is a vapor superheating section, 34 is a reforming section, 35 is a CO oxidizing section, 36a and 36b are catalytic combustion sections, and 37a and 37b are heat recovery sections. The elements of these parts are formed as a manifold for supplying and exhausting air to the surroundings, and a flat plate element having heat transfer fins therein. In the figure, the solid line indicates the flow of the liquid raw material and the raw material gas, the broken line indicates the flow of the reformed gas, and the dashed line indicates the flow of the combustion gas.

Next, the operation of this fuel reformer will be described. A liquid raw material composed of methanol and water is supplied to a liquid raw material heating unit 31. The ratio of methanol to water is set by adjusting the respective flow rates in advance so that a predetermined steam-carbon ratio (for example, 1.5) is obtained. The methanol and water are preheated by exchanging heat with the reformed gas flowing in the adjacent CO oxidizing unit 35 in the liquid raw material heating unit 31. The preheated liquid raw material is evaporated in the evaporating section 32, and the heat required for the evaporation is mainly recovered from the combustion gas exhaust heat of the heat recovery section 37a and the CO oxidizing section 3.
Supply by the heat of 5. The temperature required for evaporation is 150 ~
200 ° C., and the inlet temperature of the CO oxidation unit 35 is 200 to
240 ° C., the combustion gas temperature of the heat recovery section becomes 250 ° C. or higher, so it is a sufficiently high temperature level as a heat source for evaporation,
It can be used as heat of evaporation.

Since the steam of methanol / water is heated to the reforming temperature of 300 ° C. in the steam heating section 33, the steam heating section 33
The heat recovery unit 37b and the catalyst combustion unit 3
6a is provided. The temperature of the combustion gas in the catalytic combustion section is a high temperature of 300 ° C. or more, and retains sufficient heat to superheat the steam to 300 ° C. The superheated steam is supplied to the reforming section 34, and the methanol and steam are converted into hydrogen and carbon dioxide by a reforming reaction. Heat required for the reforming reaction is supplied from catalytic combustion units 36a and 36b provided above and below the reforming unit 34. In the catalytic combustion sections 36a and 36b, a cell off-gas (hereinafter, referred to as off-gas) exhausted from the fuel electrode of the fuel cell and containing unused hydrogen is burned with combustion air to be used as a heating source for the reforming reaction. The temperature of the reforming section 34 is such that the CO concentration in the reformed gas can be reduced to below the allowable level of the fuel cell in the CO oxidizing section 35, and a high reforming rate is ensured with respect to the flow rate of the reformed gas to be generated. Temperature (approx. 300 ° C).

[0005] The CO oxidizing air is introduced into the reformed gas exiting the reforming section 34 before entering the CO oxidizing section 35. The flow rate of the CO oxidizing air is supplied at a flow rate equal to or more than that required for oxidizing CO in the reformed gas (5 to 10 times the theoretical air amount). The CO oxidizing unit 35 is provided between the liquid raw material heating unit 31 and the heat recovery unit 37a so that the temperature of the CO oxidizing unit 35 is in a temperature range of 110 to 240 ° C. suitable for CO oxidation. The reformed gas of the CO oxidizing section 35 has
By exchanging heat with steam at 200 ° C. or combustion gas at 250 ° C., and exchanging heat with a low-temperature liquid raw material at the outlet, a temperature distribution suitable for CO oxidation is maintained. The reformed gas whose CO concentration has been reduced to an allowable level or less of the fuel cell at the outlet of the CO oxidizing unit 35 is supplied from the fuel reformer to the fuel electrode of the fuel cell.

[0006]

The conventional fuel reforming apparatus is configured as described above. For example, when the fuel reforming apparatus is used for an electric vehicle, the fuel reforming apparatus is installed in a seat together with a polymer electrolyte fuel cell stack. If it is going to be placed under the floor, the height needs to be 14 cm or less due to the arrangement. However, the structure of the fuel reformer according to the prior art has a certain height and is supplied to the upper part of the fuel reformer because the substantially square plate elements, which are the components, are stacked in the height direction. Since the exhaust gas pipe is installed, there is a problem that the entire height cannot be controlled within the limit.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems of the prior art, and has as its object to provide a compact fuel reformer having a reduced height.

[0008]

According to a first aspect of the present invention, there is provided a fuel reformer for producing a hydrogen-rich reformed gas from an alcohol, dimethyl ether, or hydrocarbon fuel. The reforming section where the reaction occurs and the catalytic combustion section where the exothermic reaction occurs are formed in a rectangular flat plate element, and these reforming sections and the flat plate element of the catalytic combustion section are closely contacted in the horizontal direction so that the long sides are horizontal. The flat plate element laminate is formed by laminating, and a manifold for air and combustion gas is provided along one short side of the flat plate element, and a manifold for reformed gas and off gas is provided along the other short side. .

A fuel reforming apparatus according to a second structure of the present invention, in addition to the first structure, further comprises at least two fuel cells penetrating through each plate element in the vicinity of the center of the plate element in parallel with the long side of the plate element. The flat plate element stack is fastened in the stacking direction through the columns of the book.

The fuel reforming apparatus according to a third configuration of the present invention, in addition to the second configuration, further comprises a plurality of disc springs having different diameters around the support, and the plate element stack having the support as an axis. And a pressing surface pressure is applied between both laminated ends to tighten the flat plate element laminated body in the laminating direction.

According to a fourth aspect of the present invention, there is provided a fuel reformer according to any one of the first to third aspects, wherein each flat plate element is provided along each short side near both short sides of the flat plate element. The flat plate element stack is fastened in the stacking direction through a plurality of columns penetrating the element.

A fuel reforming apparatus according to a fifth configuration of the present invention uses the cavity around the column as a gas manifold in addition to any one of the second to fourth configurations.

In a fuel reforming apparatus according to a sixth aspect of the present invention, in addition to any one of the first to fifth aspects, a plurality of reforming sections and catalytic combustion sections are alternately stacked in a horizontal direction. Things.

A fuel reformer according to a seventh aspect of the present invention, in addition to any one of the first to sixth aspects, further comprises a liquid material heating section for heating a liquid material mainly composed of alcohol or ether. At least one of an evaporator for evaporating the heated liquid raw material and a steam superheater for evaporating the evaporated vapor to the temperature of the reformer is provided as a rectangular flat plate element, and is stacked together with the reformer and the catalytic combustion unit. It was done.

According to an eighth aspect of the present invention, in addition to the seventh aspect, in addition to the seventh aspect, the evaporating section has a mesh or a porous foam metal made of a material having good heat conductivity inside. It is.

The fuel reforming apparatus according to a ninth aspect of the present invention, in addition to any one of the first to eighth aspects, further comprises a heat recovery unit for recovering exhaust heat of the combustion gas as a rectangular flat plate element. And a lamination unit in close contact with at least one of a reforming unit, a liquid material heating unit, an evaporating unit, and a steam superheating unit.

A fuel reforming apparatus according to a tenth aspect of the present invention is characterized in that, in addition to any one of the first to ninth aspects, CO in the reformed gas generated in the reforming section is added with a small amount of air. A rectangular CO-oxidizing unit for selectively oxidizing and converting to CO ₂ as a rectangular flat plate element, and a rectangular CO-oxidizing air introducing plate provided with a groove adjacent thereto to adjust a flow path resistance. It is provided with.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 Hereinafter, Embodiment 1 of the fuel reformer according to the present invention will be described in the case where the liquid raw materials are methanol and water. FIG. 1 is an assembled perspective view showing a typical configuration of the fuel reformer according to the first embodiment. In the drawing, reference numeral 1 denotes a manifold end plate. 2 is a liquid raw material heating section, 3 is a CO oxidation section, 4 is a CO oxidation air introduction plate, 5 is a heat recovery section, 6 is a vaporization section, 7 is a methanol combustion section which is a catalytic combustion section, 8 is a reforming section, Reference numeral 9 denotes an off-gas combustion section which is a catalytic combustion section, and each element of these sections is formed as a flat plate element having a manifold for supplying / exhausting gas around it and a heat transfer fin inside. Also, C
The O oxidizing section 3, the reforming section 8, the methanol burning section 7, and the off-gas burning section 9 are provided with CO 2 inside the heat transfer fin fixed inside.
An oxidation catalyst, a reforming catalyst, and a combustion catalyst are each filled. The detailed configuration of the flat plate element will be described later. 1
0 is a methanol inlet, 11 is an air inlet, 12 is a liquid raw material inlet, 13 is a reformed gas outlet, 14 is an off gas inlet, and 15 is a combustion gas outlet. In the present embodiment, the flat plate element has a rectangular shape, and a flat plate element having a rectangular shape is formed by closely laminating the flat plate elements in the horizontal direction such that the long sides are horizontal and the short sides are vertical. I have. In addition, a manifold is provided along the short side. In the present embodiment, the vaporizing section 6 is composed of an evaporating section for evaporating the liquid raw material and a vapor heating section for heating the evaporated vapor to the temperature of the reforming section, but the temperature of the vaporizing section is sufficiently high. When both evaporation and steam superheating can be performed, it may be constituted only by the evaporation section.

Next, the operation of the fuel reformer according to this embodiment will be described. Methanol is supplied to the methanol inlet 10 and air is supplied to the air inlet 11 of the manifold end plate 1. Methanol and air are mixed in a flow path leading to the methanol combustion section 7, and flow into the methanol combustion section 7 as a combustible air-fuel mixture. The methanol combustion section 7 has a structure in which a heat transfer fin at the center of the flat plate is filled with a combustion catalyst, and burns a combustible mixture of methanol and air on the catalyst surface. The heat generated by the combustion is transmitted to the vaporizing section 6 and the reforming section 8 adjacent to the methanol burning section 7 to increase the temperature of each plate.

When the temperature of the vaporizing section 6 becomes high enough to evaporate methanol and water, a mixed liquid of methanol and water is supplied to the liquid material inlet 12 of the manifold end plate 1.
The mixing ratio of methanol and water is set by adjusting the respective flow rates in advance so that a predetermined steam-carbon ratio (for example, 1.5) is obtained. As in the case of the above-mentioned prior art, methanol and water are preheated by exchanging heat with the reformed gas flowing in the adjacent CO oxidizing unit 3 in the liquid raw material heating unit 2. The preheated liquid raw material is evaporated in the vaporizing section 6 and the vapor of methanol and water is heated to the reforming temperature of 300 ° C.

FIG. 2 shows the structure of the vaporizing section 6. In the figure, 50 is a methanol manifold, 51 is an air manifold, 52 is a liquid raw material manifold, 53 is a reformed gas manifold, 54 is an off gas manifold, and 55 is a combustion gas manifold. Each manifold 50-55
Are arranged along the short side of the flat plate element. As shown in FIG. 2, when rectangular flat plate elements are horizontally stacked with the long side horizontal and the short side vertical as in this embodiment, and the manifold is arranged along the short side, as shown in FIG. The liquid raw material is supplied to the vaporizing section 6, that is, the vaporizing surface of the evaporating section, that is, the vaporizing surface from the side, and the liquid raw material may not be spread over the entire vaporizing surface, but may be vaporized only near the supply port.
Therefore, as shown in FIG. 2, a mesh 60 made of a good heat conductive material such as stainless steel, aluminum, or copper, a porous foamed metal, or the like is arranged in the plane to increase the surface area of a portion where vaporization occurs. Thereby, stable evaporation becomes possible. The vapor of the evaporated methanol and water passes through the air manifold 51 and the steam manifold 56 adjacent to the combustion gas manifold 55, and is introduced into the next steam superheater.

The superheated steam of methanol and water exiting the vaporizing section 6 is supplied to the reforming section 8 and converted into hydrogen and carbon dioxide by a reforming reaction. The heat required for the evaporation and reforming reactions is initially supplied from an adjacent methanol combustion section 7. The CO oxidizing air is supplied to the reformed gas exiting the reforming section 8 by the CO oxidizing air introducing plate 4 before entering the CO oxidizing section 3. The CO oxidizing air is supplied at a flow rate corresponding to an amount (3 to 5 times the theoretical air amount) that is greater than or equal to the amount necessary to oxidize CO in the reformed gas.

FIG. 3 shows an example of the configuration of the air introducing plate 4 for CO oxidation. In the figure, reference numeral 57 denotes a groove for adjusting the air flow rate by adjusting the flow path resistance, and has a predetermined depth which does not penetrate the CO oxidation air introduction plate 4. The air introduced into the air manifold 51 from the air inlet 11 of the manifold end plate 1 is branched into combustion air and CO oxidation air at the inlet of the CO oxidation air introduction plate 4. At a power generation amount of 1 kW, the flow rates of the combustion air and the CO oxidation air are 30
L / min and 3 L / min. The flow rate of the combustion air was set to a fuel utilization of 75%, and the air ratio was set to 3 (three times the theoretical air amount) with respect to hydrogen in the off-gas. On the other hand, the flow rate of the CO oxidation air is such that the CO concentration before the CO oxidation is 1%,
Was set at an air ratio of 5 (5 times the theoretical air amount). C
The O-oxidizing air introduction plate 4 is provided with corrugated fins which provide resistance to the flow of air or grooves 56 for adjusting the flow path resistance as shown in FIG. Adjust to 1/10 of the working air. The outlet of the CO oxidizing air introducing plate 4 is connected to the reformed gas manifold 53, and the reformed gas and the CO oxidizing air are premixed before entering the CO oxidizing section 3.

As in the conventional case, the temperature of the CO oxidizing section 3 is in a temperature range of 110 to 240 ° C. suitable for CO oxidation, and the reformed gas of the CO oxidizing section 3 is supplied to the inlet at 150 to 2 ° C.
By exchanging heat with steam at 00 ° C. or combustion gas at 250 ° C. and exchanging heat with a low-temperature liquid raw material at the outlet, a temperature distribution suitable for CO oxidation is maintained. The reformed gas whose CO concentration has been reduced to an allowable level or less of the fuel cell at the outlet of the CO oxidizing unit 3 is supplied from the reformed gas outlet 13 of the manifold end plate 1 to the fuel electrode of the fuel cell.

A PEFC (solid polymer fuel cell) stack is installed next to the horizontal-stacked flat-bed type fuel reformer according to this embodiment, and the reformed gas of the fuel reformer is supplied to the PE.
The fuel gas is introduced into the fuel cell inlet of the FC battery, and the off-gas at the fuel electrode outlet is introduced into the off-gas inlet 14 of the fuel reformer. The off-gas introduced into the off-gas inlet 14 is supplied to the off-gas combustion unit 9 and transfers heat to the reforming unit 8 by the heat generated by the off-gas combustion. The temperature of the reforming section 8 is increased by both methanol combustion and off-gas combustion, and the temperature 3
When the temperature reaches 00 ° C., the supply of methanol is stopped, and the operation is switched to a steady operation using only off-gas combustion. The combustion gas exiting the methanol combustion section 7 and the off-gas combustion section 9 is supplied to the heat recovery section 5.
After the heat necessary for evaporation is recovered, the exhaust gas is exhausted from the combustion gas outlet 15 of the manifold end plate. In the present embodiment, the methanol combustion section 7 is provided and used as a heat source when the fuel reforming apparatus is started up. However, another means such as an electric heater may be used. Further, the off-gas burning section 9 may be provided between the reforming section 8 and the vaporizing section 6 as in the case of the conventional example shown in FIG. Further, a heat recovery section may be provided between the evaporating section and the steam superheating section in the vaporizing section 6.

Next, an example of the configuration of the flat plate element will be described. In FIG. 4, 16 is a heat transfer flat plate, 17 is a heat insulating flat plate, 18a is a joining surface, and 18b is a reaction effective surface. FIG.
(A) is an exploded perspective view showing a configuration of a flat plate element of a methanol burning section, and (b) is a perspective view showing a flat plate element of a methanol burning section after joining.

The heat transfer flat plate 16 has a thickness of 0.5 to 1.0 mm.
The material is aluminum or an aluminum alloy having good thermal conductivity. Holes formed in the heat transfer flat plate 16 are manifolds for air 51, combustion gas 55, off gas 54, reformed gas 53, and methanol vapor 56. The dimensional shape of the plate is a rectangle whose short side, that is, height is, for example, 12 cm, and whose long side, that is, width, is 30 cm to 40 cm. The heat transfer flat plate 16 includes a joining surface 18a on the outer periphery of the flat plate and a reaction effective surface 18b at the center of the flat plate. In the figure, the joining surface 18a is hatched for easy understanding.

The heat-insulating flat plate 17 has a thickness of 2.0 to 4.0 mm.
This thickness depends on the size of the catalyst and the height of the heat transfer fins filling the reaction effective surface 18b. The outer shape of the heat-insulating flat plate 17 is the same as that of the heat transfer flat plate 16, and the inside of the effective reaction portion is hollowed out, connected to two points of each manifold, the inlet and the outlet required by the element, so that the gas flows from the inlet to the outlet. A flow path is formed. That is, in FIG.
The flow path is configured so that gas flows through the flow path. As the material of the heat insulating flat plate 17, a fluorine-based synthetic resin such as silicon or polytetrafluoroethylene having good heat insulating performance, or a metal having relatively low thermal conductivity such as expanded graphite or stainless steel is used.

An adhesive made of silicon or a fluorine-based synthetic resin or a film-shaped heat-curable adhesive is applied to the bonding surface 18a of the heat transfer flat plate 16 and the heat insulating flat plate 17 which have been processed into a predetermined shape, and both are bonded. Other methods for joining flat plates include brazing, soldering, and welding.
An appropriate joining method is selected according to the operating temperature of each flat element.
For example, an adhesive of silicon or a fluorine-based synthetic resin is used for a low temperature portion of 200 ° C. or less, and a low temperature solder of 91Sn-9Zn is used at a temperature of 180 to 260 ° C.
At a temperature of 70 ° C, a 70Zn-30Sn-based medium-temperature solder,
At 370 to 430 ° C., brazing is performed with a 95Zn-5Al-based high-temperature solder, and at higher temperatures, an Al-based or Si-based brazing sheet is used. Each of the joined plate elements is filled with a heat transfer fin on a reaction effective surface and a catalyst according to each element as necessary.
The entire fuel reforming apparatus is formed by laminating with a seal sheet made of fluoroethylene or the like interposed therebetween.

By dividing the flat plate into the heat transfer flat plate 16 and the heat insulating flat plate 17 as described above, a processing method suitable for mass production such as laser cutting of a thin plate and a thick plate can be adopted. The processing time of laser cutting is several minutes per flat plate, and the processing time when the reactive effective portion is cut without dividing into the heat transfer flat plate 16 and the heat insulating flat plate 17 is about 1 hour. Save money. Moreover, the heat-insulating flat plate 17 can reduce the heat dissipation loss to the surroundings while the heat transfer flat plate 16 keeps the thermal conductivity of the reaction effective surface 18b good.

As described above, according to the present embodiment, a rectangular flat plate element is used, and its long side is horizontal and its short side is vertical, and is horizontally stacked. The gas pipe can be installed on the side, and the height of the fuel reformer depends on the length of the short side of the flat plate element, and can be kept low. Further, since each manifold is provided along the short side thereof, a compact fuel reformer having a reduced height without effectively reducing the effective reaction area by effectively utilizing the rectangular shape of the plate element can be obtained. Note that the short side may be slightly displaced from the vertical direction. In this case, even if the flat plate element has a rectangular shape whose aspect ratio is not so large and the length of the short side is longer than 12 cm, for example, the fuel reformer Height 12c
m.

Embodiment 2 FIG. Next, a fuel reforming apparatus according to Embodiment 2 of the present invention will be described. FIG. 5 is a perspective view showing an overall configuration of a fuel reformer according to Embodiment 2 of the present invention, and FIG. 6 is a plan view showing an example of a flat plate element used in the fuel reformer of FIG. In the drawing, reference numeral 23 denotes a central portion of the flat plate element, two columns provided in parallel with the long side of the flat plate element, 24 a sealing member such as an O-ring, 25 a post disposed around the flat plate element, and 26 a column. It is a column passing through the inside of the manifold arranged along the short side of the flat plate element.
Reference numeral 101 denotes an end plate, which is formed of, for example, stainless steel or titanium together with the manifold end plate 1, and each flat plate element is sandwiched between the end plates 1 and 101. In the present embodiment, the methanol manifold 50 and the liquid raw material manifold 52 are formed around the column 23 at the center of the flat plate.

As shown in FIG. 5, rectangular end plates 1, 10
A plurality of pillars 25 are passed around the periphery of one and are arranged around the flat plate type fuel reformer. Several cm at the tip of the support 25
A thread portion having a length of 6 mm to 8 mm (M6 to M8) is provided, and both ends are tightened with nuts 29 through a disc spring. Thereby, the flat plate element laminate is fastened in the laminating direction.
A plurality of struts 26 and 23 are also passed through the peripheral portion along the short side of the flat plate element and the central portion of the flat plate element, and both ends of the struts 26 and 23 are tightened with nuts 29 and added. By applying a load also to the central portion of the flat plate occupied by the reaction effective surface occupied by the column 23 disposed at the center portion of the flat plate element, the load is uniformly applied to the reaction effective surface formed by providing the heat transfer fins and the partition plate. Good contact with the heat transfer fins reduces thermal resistance, promotes heat conduction in the laminating direction, quickly transfers heat of combustion, and allows the reforming reaction and evaporation to proceed quickly. Further, gas leakage can be prevented by tightening the peripheral portion of the manifold provided along the short side of the flat plate element with the column 26 arranged along the short side near the short side of the flat plate element.

As shown in FIG. 6, a cavity is provided around each of the two columns 23 passing through the central portion to form a manifold, and the liquid raw material and methanol are allowed to flow to effectively use the space. The liquid raw material is supplied to the vaporization section, and the methanol is supplied to the methanol combustion section. In this way, by flowing the liquid to the central portion of the reformer, the liquid can be heated and quickly evaporated. In addition, the column 26 is also passed through the center of the manifolds 51, 53 to 55 for air, combustion gas, off gas, and reformed gas arranged along the short side of the flat plate element, and the peripheral portions of these manifolds 51, 53 to 55 are formed. By preferentially tightening, gas leakage can be prevented.

FIGS. 5 and 6 show the case where two columns 23 are provided at the center of the flat plate element.
The number 3 may be two or more, and it is more preferable to arrange them in parallel with the long side of the flat plate element because a uniform load can be applied to the reaction effective surface of the flat plate element. Further, the number of the columns 26 arranged along the short side of the flat plate element may be two or more. Further, the manifold provided at the center portion is not limited to the liquid raw material 52 or the methanol 50, but may be air 5
1. Any of the combustion gas 55, the off-gas 54, and the reformed gas 52 may be used. By creating a suction or a well at the center of the flow, convection heat transfer can be promoted.

Embodiment 3 Next, a fuel reforming apparatus according to Embodiment 3 of the present invention will be described. FIG. 7 is a cross-sectional view showing the overall configuration of a fuel reformer according to Embodiment 3 of the present invention, and shows the fuel reformer cut in a vertical direction. In the present embodiment, a plurality of disc springs having different diameters from a disc spring guide are arranged around two support columns 23 arranged in the longitudinal direction of the plate element near the center of the plate element as in the second embodiment. The clamping load is applied to the flat plate element. In the figure, 27 is a disc spring guide, 28a is a large diameter disc spring, 28b is a small diameter disc spring, 29 is a fastening nut, and 30 is a sealing member, for example, an O-ring.

An O-ring groove is provided in the manifold end plate 1 and each plate element around the column 23 to prevent gas leakage, and the O-ring 30 is fitted therein. The column 23 is, for example, an M10 stainless steel bolt. A large-diameter disk spring 28a and a small-diameter disk spring 28b are provided on the disk spring guide 27 to apply a uniform surface pressure around the column. The disc spring 28a has, for example, an outer diameter of 112 mm, an inner diameter of 57 mm, and a plate thickness of 4.0.
mm disc springs are stacked, and a disc spring 28b is formed by stacking three outer diameters of 50 mm, an inner diameter of 25.4 mm, and a plate thickness of 1.9 mm.
8b, the entire height (for example, 12 cm) of the flat plate element stack is covered, and each outer diameter portion is arranged so as to abut on the manifold end plate 1, and both ends of the flat plate element stack using nuts 29 by a disc spring guide 27. Pressing surface pressure is applied between the portions via the end plate 1 to clamp the flat plate element laminate in the laminating direction.

The large-diameter disc spring 28a is subjected to a load of 350 kgf with a deformation of 1 mm, and the small-diameter disc spring 28b
Has a load of 150 kgf with a deformation of 1 mm. When the plate springs 28a and 28b were tightened so that the deformation amount was 1.15 mm, the tightening load applied to the plate element laminate was 580 kgf, and an average surface pressure of 4 kgf / cm ² was applied. At this time, a surface pressure sensor was inserted between the end plate 1 and the flat plate of the liquid raw material heating unit 2 to measure the variation of the load on the entire contact surface between the end plate 1 and the liquid raw material heating unit 2.
It was confirmed that the surface pressure was distributed in the range of ± 0.1 kgf / cm ² .

Regarding the combination of the diameters of the disc springs, the larger outer diameter is the shorter side of the flat plate, that is, the height of the fuel reformer, which is 9%.
Around 5%, when the smaller outer diameter is around 30-50%,
The best pressure distribution was shown. In this embodiment, two types of disc springs having different diameters are used. However, even if three or more types of disc springs are arranged concentrically, the same or better effect can be obtained. In the present embodiment, when the spring constant of the selected disc spring is divided by the outer diameter, it becomes 3.1, and the load applied per circumference for the same deformation amount is the same. When the surface pressure distribution was measured using disc springs having different spring constants, a good surface pressure distribution was obtained with almost no problem if the difference between the spring constant and the outer diameter of each disc spring was within 20%.

Embodiment 4 FIG. FIG. 8 is an explanatory diagram showing the configuration of the fuel reforming apparatus according to Embodiment 4 of the present invention, together with the temperature distribution of each part. The configuration of the fuel reformer is shown by cutting the fuel reformer in the vertical direction. In the present embodiment, each element of the CO oxidizing unit 3, the liquid raw material heating unit 2, the vaporizing unit 6, the reforming unit 8, and the catalytic combustion unit 9 supplies air along the short side similarly to the first embodiment.・ Exhaust manifold, formed as rectangular flat plate elements with heat transfer fins inside, and stacking these flat plate elements in horizontal direction so that long sides are horizontal and short sides are vertical To form a flat plate element laminate.

In this embodiment, a vaporizing section 6 and a liquid raw material heating section 2 are provided on both sides of a laminate in which a plurality of reforming sections 8 in which an endothermic reaction takes place and a catalytic combustion section 9 in which an exothermic reaction takes place. , And the CO oxidized portion 3 are symmetrically arranged to form a symmetrical temperature distribution as shown in the figure. In FIG. 8, three reforming blocks in which eight flat plate elements of the reforming section 8 are stacked and four catalytic combustion blocks in which two flat plate elements of the catalytic combustion section 9 that supplies combustion air and off-gas are stacked.
A block is provided, and a catalytic combustion block is arranged so as to sandwich the reforming block.

As described above, the reforming section 8 has a total of 24 layers, and the catalytic combustion section 9 has a total of 8 layers. The ratio of the number of stacked layers of the reforming section 8 and the catalytic combustion section 9 is 3: 1. The part 8 is increased.
This ratio is mainly due to the difference between the reaction rates of the reforming section 8 and the catalytic combustion section 9. The reaction rate of the reforming reaction is slower than that of the combustion reaction. Requires three times the volume of the catalyst as compared with the catalytic combustion section 9. In addition, especially in the laminating direction (thickness direction) in the modified block
In the case where a remarkable temperature difference occurs in the temperature distribution, the pitch between the catalytic combustion portions 9 may be made dense, and for example, the catalytic combustion portions 9 may be provided for every six or four reforming portions. Also,
In the present embodiment, the CO oxidizing unit 3, the liquid raw material heating unit 2,
The vaporizing section 6 is also formed by laminating a plurality of the respective flat plate elements.

As described above, in the present embodiment,
A vaporizing section 6, a liquid raw material heating section 6, and a CO oxidizing section are symmetrically arranged on both sides of a stacked body in which a plurality of reforming sections 8 in which an endothermic reaction occurs and a catalytic combustion section 9 in which an exothermic reaction occurs are alternately stacked. Since the temperature distribution is symmetrical and has a high temperature at the center, a hydrogen-rich reformed gas can be efficiently generated from the liquid raw material by effectively using thermal energy. Further, since a plurality of reforming sections 8 in which an endothermic reaction occurs and a plurality of catalytic combustion sections 9 in which an exothermic reaction occurs are alternately stacked, the bias of the temperature distribution in the stacking direction in the reforming section is alleviated and the reforming reaction is performed. It can be done efficiently. In addition, since each part is formed by laminating a plurality of the respective flat plate elements, manufacturing is facilitated by using a flat plate element having the same thickness and changing the number of laminations according to the thickness required for each part. Further, since the ratio of the number of layers is adjusted according to the difference in the reaction speed between the reforming unit 8 and the catalytic combustion unit 9, the reaction speed is uniform between the reforming unit 8 and the catalytic combustion unit 9, and the catalytic combustion unit 9 9
And the reforming section 8 can efficiently perform the reforming reaction by effectively utilizing the heat of

In each of the above embodiments, the case where a liquid raw material is used has been described. However, natural gas or the like may be used, and in this case, the liquid raw material heating unit 2 and the vaporizing unit 6 become unnecessary.

Further, the CO oxidizing section 3 and the heat recovery section 5 are not necessarily required.

[0046]

As described above, according to the first configuration of the present invention, an endothermic reaction occurs in a fuel reformer that generates a hydrogen-rich reformed gas from alcohol, dimethyl ether, or hydrocarbon-based fuel. The reforming section and the catalytic combustion section where an exothermic reaction occurs are formed in a rectangular flat plate element, and the reforming section and the flat plate element of the catalytic combustion section are laminated in close horizontal contact so that the long sides are horizontal. A flat plate element laminate was formed, and a manifold for air and combustion gas was provided along one short side of the flat plate element, and a manifold for reformed gas and off gas were provided along the other short side of the flat plate element. A compact fuel reformer with a reduced height can be obtained by effectively utilizing the rectangular shape.

According to the second structure of the present invention, in addition to the first structure, at least two struts penetrating each plate element near the center of the plate element and parallel to the long sides of the plate element. , The flat plate element laminate is fastened in the stacking direction, so that a uniform load is also applied to the reaction effective surface at the center of the flat plate element, and heat conduction in the stacking direction can be promoted.

According to the third configuration of the present invention, in addition to the above-mentioned second configuration, a plurality of disc springs having different diameters are provided around the support, and both of the plate element laminates are stacked around the support. Since the flat plate element laminate is configured to be clamped in the laminating direction by applying a pressing surface pressure between the end portions, it is possible to suppress a variation in the surface pressure in the flat plate element lamination plane.

According to the fourth configuration of the present invention, in addition to any one of the first to third configurations, each flat plate element penetrates along the short side near both short sides of the flat plate element. Since the flat plate element stack is tightened in the stacking direction through the plurality of supporting columns, gas leakage can be prevented by tightening the peripheral portion of the manifold provided along the short side of the flat plate element.

According to the fifth configuration of the present invention, in addition to any one of the second to fourth configurations, the cavity around the support is used as a gas manifold, so that the space can be effectively used. it can.

According to the sixth configuration of the present invention, in addition to any one of the first to fifth configurations, a plurality of reforming units and catalytic combustion units are alternately stacked in the horizontal direction. The reforming reaction can be efficiently performed by alleviating the bias of the temperature distribution in the stacking direction in the material part.

According to a seventh aspect of the present invention, in addition to any one of the first to sixth aspects, a liquid raw material heating section for heating a liquid raw material containing alcohol or ether as a main component, Since at least one of the evaporating section for evaporating the raw material, and the steam superheating section for superheating the evaporated vapor to the temperature of the reforming section is provided as a rectangular flat plate element, and stacked together with the reforming section and the catalytic combustion section, A hydrogen-rich reformed gas can be generated from a liquid raw material with a compact configuration having a reduced height.

According to the eighth aspect of the present invention, in addition to the seventh aspect, the evaporating portion has a mesh or a porous foam metal made of a good heat conductive material inside.
The surface area of the portion to be vaporized is increased, and stable evaporation is possible.

According to the ninth aspect of the present invention, in addition to any one of the first to eighth aspects, a heat recovery unit for recovering exhaust heat of the combustion gas is provided as a rectangular flat plate element. The stack is placed in close contact with at least one of the material section, the liquid material heating section, the evaporating section, and the steam superheating section, so that the exhaust heat of the combustion gas is effectively used in a compact configuration with a reduced height, and the efficiency is improved. Thus, a hydrogen-rich reformed gas can be generated.

According to the tenth configuration of the present invention, the first
In addition to any one of the ninth to ninth configurations, the CO oxidizing unit that converts CO in the reformed gas generated in the reforming unit into CO ₂ by selectively oxidizing by adding a small amount of air to the CO oxidizing unit has a rectangular shape. A rectangular CO oxidation air introduction plate provided with a flat plate element and provided with a groove for adjusting the flow path resistance adjacent to the plate element is provided.
Separation into CO oxidation and combustion is performed, and a predetermined amount of air can be supplied to the CO oxidation section to reduce the CO concentration.

[Brief description of the drawings]

FIG. 1 is an assembled perspective view showing a typical configuration of a fuel reformer according to a first embodiment of the present invention.

FIG. 2 is a perspective view showing a configuration of a vaporization unit according to the first embodiment of the present invention.

FIG. 3 is a perspective view showing a configuration of a CO oxidizing air introduction plate according to the first embodiment of the present invention.

FIG. 4 shows a configuration of a flat plate element of a methanol combustion section according to Embodiment 1 of the present invention, where (a) is an exploded perspective view,
(B) is a perspective view after joining.

FIG. 5 is a perspective view showing an overall configuration of a fuel reforming apparatus according to a second embodiment.

FIG. 6 is a plan view showing an example of a flat plate element used in the fuel reformer of FIG.

FIG. 7 is a cross-sectional view showing an overall configuration of a fuel reforming apparatus according to Embodiment 3 of the present invention.

FIG. 8 is an explanatory diagram showing the overall configuration of a fuel reforming apparatus according to Embodiment 4 of the present invention, together with the temperature distribution of each part.

FIG. 9 is a configuration diagram showing a basic configuration of a conventional fuel reforming apparatus having a flat plate laminated structure.

[Explanation of symbols]

1 Manifold end plate, 2 Liquid material heating section, 3 CO
Oxidizing unit, 4 CO air oxidizing plate, 5 heat recovery unit, 6
Vaporization section, 7 methanol combustion section, 8 reforming section, 9 off gas combustion section, 10 methanol inlet, 11 air inlet, 12 liquid raw material inlet, 13 reformed gas outlet,
14 Off gas inlet, 15 Combustion gas outlet, 16
Heat transfer flat plate, 17 heat insulating flat plate, 18a joining surface, 18b
Effective reaction surface, 23 plate center support, 24 seal member, 25 plate support, 26 plate support passing through inside of manifold, 27 disk spring guide, 28a large diameter disk spring, 28b small diameter Belleville spring, 29 tightening nut, 30 O-ring, 31
Liquid raw material heating section, 32 evaporation section, 33 steam heating section, 3
4 reforming section, 35 CO oxidation section, 36a, 36b catalytic combustion section, 37a, 37b heat recovery section, 50 methanol manifold, 51 air manifold, 52 liquid raw material manifold, 53 reformed gas manifold, 54 off gas manifold, 55 combustion gas Manifold, 5
6 steam manifold, 57 grooves, 60 mesh, 1
01 End plate.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Norio Mitsuda 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Within Mitsui Electric Co., Ltd. (72) Inventor Kazutoshi Kinno 2-2-2 Marunouchi, Chiyoda-ku, Tokyo No. 3 Mitsubishi Electric Corporation F-term (reference) 3D038 CA11 CB01 CC00 CC18 CD19 4G040 EA02 EA03 EA06 EB01 EB12 EB14 EB23 EB44 EC08

Claims (10)

[Claims] In a fuel reformer for producing a hydrogen-rich reformed gas from alcohol, dimethyl ether or hydrocarbon fuel, a reforming section in which an endothermic reaction occurs and a catalytic combustion section in which an exothermic reaction occurs have a rectangular shape. A flat plate element is formed, and the flat plate elements of the reforming section and the catalytic combustion section are closely stacked in the horizontal direction so that the long sides are horizontal to form a flat plate element laminate. A fuel reformer comprising a manifold for air and combustion gas provided along one side, and a manifold for reformed gas and off gas provided along the other short side. 2. The flat plate element stack is fastened in the stacking direction through at least two columns penetrating each flat plate element near the center of the flat plate element and parallel to the long side of the flat plate element. The fuel reformer according to any one of the preceding claims. 3. A plurality of disc springs having different diameters are provided around the support, and a pressing force is applied between both stacking ends of the flat element stack with the support as an axis to stack the flat element stack in the stacking direction. The fuel reformer according to claim 2, wherein the fuel reformer is configured to be tightened. 4. The flat plate element stack is fastened in the stacking direction through a plurality of pillars penetrating each flat element in the vicinity of both short sides of the flat element along the short side. 4. The fuel reforming apparatus according to any one of 3. 5. The fuel reformer according to claim 2, wherein a cavity around the support is used as a gas manifold. 6. The fuel reforming apparatus according to claim 1, wherein a plurality of reforming sections and catalytic combustion sections are alternately stacked in a horizontal direction. 7. A liquid material heating section for heating a liquid material mainly containing alcohol or ether, an evaporating section for evaporating the heated liquid material, and a vapor heating section for heating the evaporated vapor to a temperature of the reforming section. 7. The fuel reforming apparatus according to claim 1, wherein at least one of the elements is provided as a rectangular plate element, and is stacked together with the reforming section and the catalytic combustion section. 8. The fuel reformer according to claim 7, wherein the evaporator has a mesh or a porous foam metal made of a material having good thermal conductivity inside. 9. A heat recovery unit for recovering exhaust heat of the combustion gas is provided as a rectangular flat plate element, and is in close contact with at least one of a reforming unit, a liquid raw material heating unit, an evaporation unit, and a steam superheating unit. 9. The fuel reformer according to claim 1, wherein the fuel reformers are stacked. 10. CO 2 in a reformed gas generated in a reforming section is selectively oxidized by adding a small amount of air to thereby obtain CO _2.
And a rectangular CO air introducing plate having a rectangular flat plate element and a groove adjacent to the CO oxidizing portion for adjusting a flow path resistance. 10. The fuel reformer according to any one of 1 to 9.