JPH01168332A - Apparatus for reforming fuel - Google Patents

Abstract

PURPOSE:To ensure the retention of sufficient quantity of catalyst and improve reaction performance using a small apparatus, by providing an inner cylinder concentrically within an outer cylinder, dividing the space between said cylinders by a helical plate, and disposing helical heating layers and reforming catalyst layers alternately, each of them being located adjacent to each other. CONSTITUTION:An inner cylinder 10 is provided concentrically in an outer cylinder 11, wherein helical heating layers 2 and helical reforming catalyst layers 1 are formed, the layers being located alternately adjacent to each other, by dividing the space between the cylinders 11 and 10 by a plurality of helical plates 12. The reforming catalyst layers 1 are loaded with reforming catralysts 3 to steam-reform the raw material to be reformed, while a means 6 for supplying the raw material to be reformed from the outside and a means 8 for delivering reformed gas are connected to said layer 1. Means 7a, 7b, 9 for supplying and discharging heat medium of high temperature are connected to the heating layers 2. Consequently, ineffective spaces in the reforming apparatus are eliminated, increasing thereby the area of heat-transfer surfaces between the heating layers and the reforming catalyst layers, further ensuring the retention of sufficient quantities of catalysts, leading to a small apparatus having high reaction performance.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a fuel reformer that generates hydrogen by steam reforming alcohol or hydrocarbon fuel, and particularly relates to a fuel cell system and a hydrogen production device. The present invention relates to a fuel reformer suitable for.

[Conventional technology]

As shown in Japanese Unexamined Patent Publication No. 53-78983, conventional reforming equipment uses a cylindrical reaction tube for the reaction section, and a reforming catalyst is packed inside the reaction tube. . Furthermore, in order to efficiently heat the reforming catalyst, a spacer was provided inside the reaction tube to form an annular □ catalyst layer to improve heat transfer characteristics. In addition, in the heat transfer section for heating the reaction tube, in order to promote heat transfer from the burner combustion chamber that generates combustion gas as a heat source and the combustion gas, the combustion gas flow path is filled with heat transfer particles. A heat layer is provided. In addition, the combustion chamber space and the gas flow path space of the heat transfer layer are required, and especially in the gas flow path space of the heat transfer layer, there is a gap between the columnar arrays of reaction tubes, so there is a dead space compared to the spacing between one reaction tube array. The space becomes larger.

In such conventional reaction tube type fuel reformers, it was thought that these extra spaces were necessarily necessary.

[Problem that the invention seeks to solve]

In the reaction tube type fuel reformer according to the above conventional technology, 1
An extra space was provided outside the reaction tube to uniformly heat the modified WM medium by promoting heat transfer by increasing the flow rate of the heating fluid and by reducing the thickness of the reforming catalyst layer. For this reason, in order to improve the size and performance of the reformer, no consideration has been given to a structure that eliminates the surplus space outside the reaction tube, and in order to make the reformer smaller, it is necessary to reduce the size of the conventional lock structure. It stayed in. Also,
In a reaction tube type reformer, the heat transfer area of one reaction tube cannot be made very large, so the amount of catalyst packed cannot be increased. In particular, in methanol reforming, where the throughput of feedstock cannot be large relative to the amount of catalyst, a larger amount of catalyst is required for the same throughput than in hydrocarbon reforming, so the reformer needs to be larger. was there. In addition, the weight of the catalyst in the upper layer directly acts on the reforming catalyst at the bottom of the reforming catalyst layer, so that it may be damaged. As described above, the conventional reforming apparatus for methanol reforming requires a large number of reaction tubes and has a large surplus space, resulting in an increase in the size of the reforming apparatus.

An object of the present invention is to eliminate the need for surplus space, increase heat transfer surface quality, and secure a sufficient amount of catalyst.

[Means for solving the problem] The present invention is characterized by an outer cylinder, an inner cylinder provided concentrically within the outer cylinder, and A spiral heating layer and a spiral reforming catalyst layer are formed adjacent to each other by partitioning the space formed between the outer cylinder and the inner cylinder with a plurality of spiral plates. The catalyst bed is filled with a reforming catalyst for steam reforming the reforming raw material, and the reforming catalyst bed is connected to a means for supplying the reforming raw material from the outside and a means for taking out the reformed gas, and A means for supplying and discharging a high temperature heat medium is connected to the heating layer.

[Effect]

In the present invention, the space between the outer cylinder and the inner cylinder is partitioned by a spiral plate, and the spiral heating layer and reforming catalyst layer are arranged adjacent to each other, so there is no need to provide extra space such as a decimal space. (A sufficient heat transfer area can be provided. Also, heat loss can be reduced because the heat from the heating layer can be directly transferred to the reforming catalyst layer. Furthermore, the catalyst is held by a spiral plate.

The load acting on the catalyst packed in the lower part can be reduced and damage to the catalyst can be prevented.

〔Example〕

Hereinafter, one embodiment of the present invention will be explained with reference to FIGS. 1 and 2.6 An inner cylinder 1o is provided concentrically inside an outer cylinder 11, and between the outer cylinder 11 and the inner cylinder 10, An even number of spiral plates 12 are arranged, and the spiral plates 12 and the outer cylinder 1],
A spiral space is formed by the inner fFli i O. This spiral space is filled with reforming catalysts 3 every other space to form a reforming catalyst layer 1. The inside of the spiral space and inner cylinder formed on both sides of this reforming catalyst layer 1 is a heating layer 2 through which a high-temperature gas flow path flows, and this heating layer 2 is filled with a reforming catalyst from high-temperature gas. In order to promote heat transfer to layer 1, heat transfer particles 5, which are heat-resistant alumina spheres, are filled. In addition, in order to generate the amount of heat required as a heat source, the lowers a and 7b, which supply fuel and air to the heating layer 2, are filled with a combustion catalyst 4, as shown in FIG. Inner cylinder 10
The combustion catalyst 4 and heat transfer particles 5 inside are held by ceramic honeycomb support plates 1; 3. Raw materials such as methanol are supplied to the reforming catalyst W11 through the raw material port 6. The raw material that has entered the reforming catalyst layer 1 receives heat from the high temperature gas passing through the heating layer 2 via the spiral plate 12 and the inner cylinder 10, and as the reforming reaction progresses, it becomes a hydrogen-rich reformed gas. The generated reformed gas is taken out from the reformed gas outlet 8. On the other hand, high-temperature gas serving as a heating source for the reformed gas is obtained by burning the fuel in the heating layer 2 and the combustion catalyst 4 filled in the air-filled lowers a and 7b. The generated high-temperature combustion gas rises through the inner cylinder 10 and is guided to a spiral heating layer 2 disposed around the upper part of the inner cylinder 10. In the inner cylinder 10 and the heating layer 2.

The heat of the high-temperature gas is applied to the reforming catalyst layer 1 through the spiral plate 12 and the wall of the inner cylinder 10. This is achieved by the effective action of convection, conduction, and radiation heat transfer due to the presence of the heat transfer particles 5. The temperature of the high-temperature gas that has heated the reforming catalyst layer 1 drops, and it is exhausted from the exhaust chamber 9 as exhaust gas.

In this embodiment described above, in the case of a fuel reformer that generates hydrogen at 75 Nms/h, the height of the conventional one is 2.
, 6 m, and the diameter is 0.7 m, whereas 1
In the case of this example, the height is 1.5 m and the diameter is 0.45 m.
Therefore, it is possible to reduce the size by about 1/4 in terms of volume. In addition, the overall heat transfer coefficient is 50kcaQ/m”
h'C, approximately 110 kcaQ/m2h' in this example
It is possible to obtain a heat transfer coefficient more than twice that of C and achieve high efficiency.6 FIG. 3 shows another embodiment of the present invention in which the reformed gas is subjected to self-heat exchange. In this embodiment, like the previous embodiment, the reforming catalyst layer 1 and the heating layer 2 are separated by a spiral plate 12 and arranged adjacent to each other. The reforming catalyst layer 1 is filled with reforming catalysts 3, which are supported by a ceramic honeycomb plate at the lowest part of the spiral passage. The reforming raw material is supplied from the raw material population 6, distributed to each reforming catalyst WJ1, passes through each reforming catalyst layer 1, and is reformed into hydrogen-rich gas. The generated hydrogen-rich reformed gas is collected in the upper part of the inner cylinder 10 from the upper part of the spiral passage, and flows downward in the inner cylinder 10. At this time, the reforming catalyst layer 1 is
After that, the reformed gas is taken out from the reformed gas outlet 8 at the bottom of the inner cylinder 10. On the other hand, the heating layer 2 in this embodiment is composed of a layer of combustion catalyst 4 and a layer of heat transfer particles 5, and the combustion catalyst layer is provided on the fuel/air inlet section 7 side of the heating layer 2. As the combustion catalyst 4,
For example, a granular catalyst supporting palladium or the like is used, and the heat transfer particles 5 are made of a heat-resistant material such as alumina particles. The fuel supplied from the fuel/air inlet 7 to the lower part of the spiral heating layer 2 is catalytically combusted in the layer of the combustion catalyst 4 and becomes high-temperature combustion gas, which ascends the spiral heating layer 2 to the adjacent spiral. The reforming catalyst layer 1 is heated. In this example, as in the previous example, due to the presence of heat transfer particles 5, convection,
This is achieved through the effective use of conduction and radiation heat transfer methods.

The combustion gas reaches the top of the spiral heating layer 2 while heating the reforming catalyst layer 1, is collected as exhaust gas in an exhaust gas header formed at the top of the outer cylinder 11, and is exhausted to the outside from the exhaust pipe 9. This embodiment also has the same effects as the above-mentioned embodiments, and can be significantly downsized compared to the conventional reaction tube type reformer. Furthermore, since a high-temperature heat source is created directly within the heating layer through catalytic combustion, there is no need to provide a separate combustor, which is effective in simplifying the device.

Still another embodiment of the invention is shown in FIG. This embodiment is particularly effective for high-purity hydrogen production equipment using alcohol as a raw material and fuel reforming equipment for fuel cell power generation systems. An apparatus using alcohol as a raw material requires an evaporator to be provided in front of the fuel reformer, but in this embodiment, the evaporator is provided inside the fuel reformer. Similar to the first embodiment, this fuel reformer has a spiral space separated by a spiral partition wall (spiral plate) 12 between an inner cylinder 10 and an outer cylinder 11, and a reforming catalyst layer. 1 and heating layers 2 are alternately arranged adjacent to each other. Further, an evaporation layer 13 is provided below the reforming catalyst layer 1.

Heat transfer particles 5 are provided in the evaporation layer 13 to improve the heat transfer coefficient.
It is filled with alumina particles. The heat transfer particles 5 are supported by a honeycomb support plate provided at the bottom of the spiral reforming catalyst layer 1. When the raw material supplied from the raw material population 6 passes through the evaporation layer 13, it is evaporated and superheated to the reforming catalyst Pylt.
is supplied to Here, a methanol reformer to which this embodiment is considered to be most effective will be explained as an example. A mixed raw material of methanol and water is supplied from the raw material inlet 6. The raw material is evaporated in the evaporation layer 13 by heat transfer from the heating layer 2.

overheated. Inner f? A catalytic combustion section 4 is provided below the heating layer 2 in the same manner as in FIG. 2, and a high temperature combustion gas of 800 DEG C. to 1000 DEG C. is generated in this catalytic combustion section 4. The evaporation layer 13 is located between the inner cylinder 1 and the catalytic combustion section 4.
Although the evaporation layer 13 is provided close to the evaporation layer 13 via the
Breakage of the inner cylinder 10 due to heat can be prevented. Further, although methanol undergoes thermal decomposition at high temperatures, the wall temperatures of the inner cylinder 10 and the spiral plate 1.2 do not become too high, so that thermal decomposition of methanol can be prevented. Furthermore, since the methanol reforming catalyst 3 has a low heat resistance temperature of 350°C to 400°C, the reforming catalyst 3 was conventionally heated with heat transfer oil such as Dowsum, but in this example, the reforming catalyst layer The combustion gas passing through the heating layer 2, which corresponds to one population position, has a temperature of 500°C to 550°C, which is cooled by the evaporation layer 13, so there is no need to worry about catalyst damage even without heating with heat transfer oil. There is no need for a heat transfer furnace to heat the heat transfer oil.

As explained above, in this example, thermal decomposition of methanol and thermal damage to the reforming catalyst can be prevented even with direct heating, so the equipment can be simplified compared to the conventional method using heat transfer oil. 5 and 6 show still another embodiment of the present invention. In FIG. 5, the spiral plate 12 is 6, the spiral plate 12 is provided with protrusions 12b. According to these examples, the heat transfer efficiency can be further improved.

In all of the above embodiments, since the reforming catalyst is supported by the spiral plate 12, damage to the lower catalyst due to the weight of the catalyst can be prevented.

Although a combustion catalyst is used in the above embodiment, if high-temperature gas is easily obtained from other processes, a heating layer of heat transfer particles may be used without using a combustion catalyst.

According to the embodiment of the present invention described above, by forming the reforming catalyst layer and the heating layer into a spiral shape separated by spiral plates, there is no wasted space, and the heat transfer area for the required amount of catalyst can be secured by reforming. This is possible by changing the height or diameter of the device. Further, since the heating layer, which is a heating source and a heat receiving source, and the reforming catalyst layer are arranged adjacent to each other, a good heat transfer function can be obtained, and since no dead space is created, the size can be significantly reduced. In order to increase the capacity of the reformer, it is sufficient to expand the device in a similar manner. Furthermore, since the flow path area of the combustion gas and the length of the reforming catalyst layer can be appropriately set, it is possible to easily improve the heat transfer coefficient and secure the distance necessary for the catalytic reaction. Further, according to this embodiment, since the spiral plate can support the weight of the catalyst, damage to the catalyst can be prevented and the life of the catalyst can be extended. Since the heating layer is filled with a combustion catalyst, high-temperature gas can be generated by catalytic combustion just by supplying fuel, etc., and there is no need to install a separate combustor as in the past, and the high-temperature gas generated can be generated by simply supplying fuel etc. Since the heat of the gas can be directly transferred to the reforming catalyst layer, heat loss can also be reduced.

Furthermore, since the reforming catalyst layer is heated from within the inner cylinder by passing high-temperature gas or reformed gas into the inner cylinder, heat loss can be reduced. Thus, according to this embodiment, a small, compact, and highly efficient fuel reformer can be obtained.

〔Effect of the invention〕

As described above, the present invention provides an inner cylinder concentrically within an outer cylinder, partitions the space between the outer cylinder and the inner cylinder with a spiral plate, and connects a spiral heating layer and a reforming catalyst layer. By arranging them adjacent to each other, there is no wasted space in the reformer, the heat transfer area from the heating layer to the reforming catalyst layer can be increased, and a sufficient amount of catalyst can be secured. Therefore, it is possible to obtain a fuel reformer that is small in size, has high heat transfer performance, and has high reaction performance. Further, according to the present invention, since the weight of the catalyst can be supported by the spiral plate, damage to the catalyst at the lower part of the reforming catalyst layer can be prevented, and the life of the catalyst can be extended.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway perspective view of an embodiment of the present invention;
FIG. 2 is a sectional view illustrating the structure of the inner cylinder portion of the device shown in FIG. 5 and 6 are perspective views of portions of a spiral plate showing still other embodiments of the present invention, respectively. DESCRIPTION OF SYMBOLS 1... Reforming catalyst layer, 2... Heating layer, 3... Reforming catalyst, 4... Combustion catalyst, 5... Heat transfer particles, 6... Raw material inlet, 7... Fuel/air inlet, 7a...Fuel inlet 0
．． 7b...Air population, 8...Reformed gas outlet, 9...
・Combustion gas outlet, 10...Inner cylinder, 11...Outer cylinder, 1
2...Spiral board, 12a...1st circle/3 Honeyker large degree moxibustion treatment■ 3 Diagram?烃゛）尤η′ス♂ 7 Passenger air entrance dormitory 4 Figure 5 Figure ¥J6 Figure 12b γb

Claims (1)

[Claims] 1. An outer cylinder and an inner cylinder provided concentrically within the outer cylinder are provided, and a space formed between the outer cylinder and the inner cylinder is partitioned by a plurality of spiral plates. By forming a spiral heating layer and a spiral reforming catalyst layer adjacent to each other, the reforming catalyst layer is filled with a reforming catalyst for steam reforming the reforming raw material,
A means for supplying a reforming raw material from the outside and a means for taking out reformed gas are connected to the reforming catalyst layer, and a means for supplying and discharging a high temperature heat medium is connected to the heating layer. Fuel reformer. 2. A fuel reformer according to claim 1, characterized in that the heating layer is filled with heat transfer particles. 3. A fuel reforming device according to claim 2, characterized in that the inside of the inner cylinder is also a heating layer, and the inside of the inner cylinder is filled with heat transfer particles. 4. A fuel reforming device according to claim 1, characterized in that a combustion catalyst is filled in the most upstream part of the heating layer to catalytically combust the fuel. 5. In claim 1, the downstream side of the spiral reforming catalyst layer and one end side of the inner cylinder are communicated, and the reformed gas from the reforming catalyst layer is passed through the inner cylinder and then to the outside. A fuel reformer characterized in that it is configured to discharge. 6. Claim 1 is characterized in that a layer filled with heat transfer particles is provided at the most upstream part of the reforming catalyst layer, and the reforming raw material is evaporated in this layer of heat transfer particles. fuel reformer. 7. A fuel reforming device according to claim 1, characterized in that plate rows or protrusions are formed in a spiral shape.