JPH07291602A - Reforming device - Google Patents

Abstract

PURPOSE:To prevent inclination of the top of a catalyst layer caused by inclination of a reforming device and to reduce difference in a temperature distribution of the catalyst layer. CONSTITUTION:Since heat transfer particles of a heat transfer layer 12 set on a catalyst layer 10 are smoothly dropped with the movement of the top of the catalyst layer 10 even if the catalyst of the catalyst layer 10 is densely packed from the beginning of packing and the top of the catalyst layer 10 is dropped, a space will not occur between the catalyst layer 10 and the heat transfer particle layer 12. Since a pressing plate 13 on the heat transfer particles is elastically forced by a spring 14, the catalyst layer 10 is always in a pressed state by the heat transfer particle layer 12 and the pressing plate 13. Further, since the temperature of the heat transfer particle layer 12 is raised by heat obtained from a heating space, the upper part of the catalyst layer 10 is made into a thermally insulated state to reduce the temperature distribution of the catalyst layer 10. Besides, in the case of supplying a fuel gas from the top of the catalyst layer 10, when the fuel gas is passed through the heat transfer particle layer 12, the fuel gas receives heat from the heat transfer particles of the heat transfer layer 12 and is supplied in a heated state to the catalyst layer 10.

Description

Detailed Description of the Invention

The present invention relates to a reformer, and more particularly to a catalyst retainer for the reformer.

[0002]

2. Description of the Related Art A fuel cell uses a hydrogen-rich gas and oxygen in the air to generate electric power. This hydrogen-rich gas is used in a reformer to steam reform a raw material gas such as natural gas or methanol. Is generated by. Figure 4
FIG. 1 shows a schematic cross-sectional view of the main part of a conventional reformer. As shown in the figure, the reformer is a partition cylinder 10
1 and an inner cylinder 102 and an outer cylinder 1 which are concentrically arranged inside and outside thereof.
03, and the lower end of the inner cylinder 102 and the outer cylinder 103.
The lower end of is connected so that a space 104 formed by the inner cylinder 102 and the partition cylinder 101 and a space 105 formed by the outer cylinder 103 and the partition cylinder 101 communicate with each other. Furthermore, the opening at the upper end of the inner cylinder 102 is covered with a combustion chamber top plate 106. The outer cylinder 103 and the partition cylinder 101 are extended above the upper end of the inner cylinder 102, and the upper end openings of the outer cylinder 103 and the partition cylinder 101 are covered by a reformer top plate 107. Space 1 formed by the partition cylinder 101 and the inner cylinder 102
The catalyst layer 108 is provided at 04. The upper surface of the catalyst layer 108 is provided below the top plate 106, and the catalyst stopper 10 for holding the catalyst is provided on the lower end side of the catalyst layer.
9 is provided from the lower end of the partition cylinder 101 to the inner cylinder 102. Further, a donut type catalyst holding plate 110 is provided on the catalyst layer 108.

[0003]

By the way, the above-mentioned conventional reformer has the following problems. The catalyst filled in the reforming device may be vibrated in the reforming device during transportation, and the inner cylinder 1 may be subjected to heat cycle.
02 and the partition cylinder 101 repeatedly expand and contract, the catalyst moves and the catalyst becomes more densely packed, the catalyst particles collide with each other, or the wall surface of the member in contact with the catalyst rubs against each other. And pulverize. In this way, the upper surface 108a of the catalyst layer 108 is lowered due to the increase in the packing density of the catalyst and the pulverization due to the vibration and the thermal cycle.

At this time, since the catalyst pressing plate 110 on the catalyst layer 108 is donut-shaped and thick and is in contact with the wall surfaces of the partition cylinder 101 and the inner cylinder 102, there are many contact portions and the space 104. It is easy to get caught inside. Therefore, as the upper surface 108a of the catalyst layer 108 lowers, it cannot move downward in the space 104, and a gap S is formed between the pressing plate 110 and the catalyst layer 108 upper surface 108a as shown in FIG. When the reforming device is tilted in the state where the gap S is formed between the catalyst pressing plate 110 and the upper surface 108a of the catalyst layer 108 as described above, the upper surface 108 of the catalyst layer 108 is formed.
As shown in FIG. 6, a is inclined.

For example, when a fuel gas consisting of water vapor and a raw material gas is supplied from above the catalyst in a state where the upper surface of the catalyst layer 108 is inclined as described above, a portion where the upper end is lowered and a portion where the upper end is raised are formed. By comparison, due to the pressure loss relationship of the supplied fuel gas, the fuel gas easily flows into the lower part of the upper end, more fuel gas flows in, and the endothermic reaction can be biased and the temperature distribution in the catalyst layer Unevenness occurs.

Further, as shown in FIG. 6, the upper surfaces 108a of the catalyst portions at points A and B located at the same height h are also
Since the positions from to are different, the progress of the reaction is different, which also causes the temperature distribution in the catalyst layer to be non-uniform. Also, when the fuel gas is introduced from below in the state where the upper end of the catalyst is inclined as described above, due to the pressure loss, the fuel gas easily flows into the portion where the upper end is low, and more fuel gas is generated. Inflow, the endothermic reaction can be biased, and the temperature distribution in the catalyst layer becomes uneven.

The present invention has been made in view of the above problems, and an object of the present invention is to prevent the inclination of the upper surface of the catalyst layer caused by the inclination of the reforming device and to reduce the difference in the temperature distribution of the catalyst layer. To do.

[0008]

In order to achieve the above-mentioned object, in the invention of claim 1, the first cylinder and the first cylinder are provided on the outer periphery of the first cylinder at a predetermined interval. A second cylinder from the top plate position, which has a second cylinder provided with the second cylinder, a top plate that closes the upper end opening of the first cylinder, and a heating space surrounded by the top plate and the first cylinder. An upper end of which extends upward, and a catalyst layer through which the fuel gas used for the reforming reaction passes is provided between the first cylinder and the second cylinder, and the upper surface of the catalyst layer is In the reforming tube below the top plate, the heat transfer particle layer is provided in a state of being stacked on the catalyst layer, the upper surface of the layer of the heat transfer particles is located above the top plate,
Further, a catalyst pressing plate is elastically urged on the heat transfer particle layer.

According to a second aspect of the present invention, there is provided a reforming apparatus having a partition cylinder, an inner cylinder provided inside the partition cylinder, and an outer cylinder provided outside the partition cylinder. The inner cylinder has a top plate, and a heating space is formed by the inner cylinder and the top plate, and the space surrounded by the partition cylinder and the inner cylinder is up to a position that does not reach the top plate position. Is filled with catalyst,
Further, the upper part of the catalyst is filled with heat transfer particles from above the top plate position, and the pressing plate is elastically pressed by the pressing means on the upper part of the heat transfer particles filled as described above. To do.

According to a third aspect of the invention, in the second aspect of the invention, the elastic pressing means is a metal spring. According to the invention of claim 4, in the invention of claim 2, the heat transfer particles are at least one kind selected from silica, ceramics, and metal.

[0011]

With the construction of the first and second aspects, the following operation is achieved. Due to pulverization of the catalyst, etc., the catalyst is denser from the beginning of filling, that is, even if the upper surface of the catalyst layer goes down, the heat transfer particles in the heat transfer particle layer provided on the catalyst layer are fluid, It smoothly moves downward with the movement of the upper surface of the catalyst layer. Therefore, no space is created between the catalyst layer and the heat transfer particle layer holding the catalyst layer. Further, since the pressing plate on the heat transfer particle layer is elastically biased by the elastic body, the catalyst layer is always pressed by the heat transfer particle layer and the pressing plate.

Further, since the heat transfer particle layer is heated by the heat obtained from the heating space, the upper part of the catalyst layer is kept warm by the heat transfer particle layer, which reduces the uneven temperature distribution of the catalyst layer. . In addition, when the fuel gas for the reforming reaction is supplied from above the catalyst layer, the fuel gas passes through the heat transfer particle layer and is supplied to the catalyst. Since the heat transfer particles in the heat transfer particle layer are heated by the heat from the heating space, heat is applied to the fuel gas when the fuel gas passes through. As a result, the fuel gas is supplied into the catalyst layer in a temperature-increased state, and the temperature drop above the catalyst layer is prevented.

Further, even if the wall of the cylinder in which the catalyst layer is provided expands and contracts due to the heat of the reforming reaction and the upper surface of the catalyst layer moves up and down, the heat transfer particle layer and the pressing plate are correspondingly moved. Since the elastic body moves up and down and expands and contracts, the catalyst can be pressed down in response to expansion and contraction of the cylinder.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A reformer according to an example of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic cross-sectional view of a main part of the reforming apparatus of this embodiment. As shown in the figure, the reformer has a partition cylinder 1 and an inner cylinder 2 and an outer cylinder 3 which are concentrically arranged inside and outside the partition cylinder 1. The lower end of the inner cylinder 2 and the outer cylinder 3 are separated from each other. The lower end means an inner cylinder 2 and a partition cylinder 1.
The space 4 formed by the outer cylinder 3 and the space 5 formed by the partition cylinder 1 are connected so as to communicate with each other. Further, the opening at the upper end of the inner cylinder 2 is covered and closed by the combustion chamber top plate 6. The outer cylinder 3 and the partition cylinder 1 are the inner cylinder 2
Of the outer cylinder 3 and the partition cylinder 1 are covered by a reformer top plate 7. At the center of the reformer top plate 7, there is provided an inlet 8 for a fuel gas composed of steam used for the reforming reaction and a raw material gas such as natural gas or methanol.
In addition, an outlet 9 for the reformed gas generated by the reaction in the catalyst layer 10 described later is provided on the upper side wall of the outer cylinder 3.

A catalyst layer 10 is provided in a space 4 formed by the partition cylinder 1 and the inner cylinder 2. However, the upper surface 10 a of the catalyst layer 10 is provided so as to be below the position of the fuel quality top plate 6. Further, on the lower end side of the catalyst layer 10, a catalyst stopper 11 is provided from the lower end of the partition cylinder 1 to the inner cylinder 2 for holding the catalyst layer 10. A heat transfer particle layer 12 is laminated on the catalyst layer 10. The upper surface 12 of the heat transfer particle layer 12
a is higher than the fuel quality top plate 6. Further, a pressing plate 13 is elastically urged on the heat transfer particle layer 12 by a spring 14, and the heat transfer particle layer 12 is pressed toward the catalyst layer 10 by the spring 14 and the pressing plate 13. It is in a state. The pressing plate 13 is provided with a hole 13a for passing fuel gas,
Further, the outer circumference of the pressing plate 13 is configured to be slightly smaller than the inner circumference of the outer cylinder 3 so that it can be moved up and down easily in the outer cylinder.

The reformed gas generated by the reforming reaction in the catalyst layer 10 passes through the space 5 formed by the partition cylinder 1 and the outer cylinder 3. In a space 15 surrounded by the inner cylinder 2 and the fuel quality top plate 6, a combustion cylinder 17 having a burner 16 at the bottom is provided. Combustion gas generated by the combustion of the burner 16 rises along the combustion cylinder 17, changes its direction by the fuel quality top plate 6, and passes around the inner cylinder 2 and the outer cylinder 3 of the reformer to be reformed. It is configured to raise the temperature of the tube. The combustion gas causes the temperature of the catalyst layer 10 and the heat transfer particle layer 12 to rise.

The catalyst used in this example has a particle size of Φ3.
Spheres and noble metal catalysts were used, and the packing density was 1 kg / liter. Further, as the heat transfer particles, those having a particle size of Φ3 spheres and silica type were used, and the packing density thereof was set to 1 kg / liter. When the packing density of the catalyst is 1 kg / l, the packing density of the heat transfer particles may be in the range of 0.9 to 1.1 kg / l. (Experiment) The reformer of this embodiment, the conventional reformer shown in FIG. 5, and the temperature distribution inside the catalyst and above the upper end of the catalyst when the reformer was operated after the inclination was added to each The results are shown below in FIG. (Experimental conditions) The temperature distribution was investigated by operating the reformer after incorporating it into the reforming system. At the time of assembling this system, each reformer is inclined by 45 degrees or more.

As shown in FIG. 3, a specific temperature measuring position in the catalyst is H ₁ 20 mm upward from the lower end of the catalyst.
The temperature of the catalyst located approximately in the center between the partition cylinder 1 and the inner cylinder 2 was measured at four positions at an angle of 90 degrees in the circumferential direction of the cylinder (T ₁
~ T ₄ ). The measurement position above the upper end of the catalyst is H ₂ 100 mm downward from the reformer top plate 7 or the top plate 107.
The temperature of the location of, measured four angle 90 degree intervals in the circumferential direction of the tube (T ₅ ~T _8). The thickness of the inner cylinder, the partition cylinder and the outer cylinder of the reformer used for the measurement was 2 mm.

As is apparent from FIG. 2, the modification of this embodiment.
In the device, inside the catalyst layer (T₁~ T _Four) Temperature distribution
Has been reduced. In the reformer of this embodiment, this is
Even if the quality device itself tilted, the catalyst layer did not tilt.
It is. Furthermore, the temperature (T_Five~ T₈)
Looking at, in the reformer of this example, the temperature becomes high.
And the difference from the inside of the catalyst is small.

As a result, the heat above the filled catalyst is less likely to be removed, and the temperature above the catalyst is prevented from lowering. (Other matters) To prevent the catalyst particles and heat transfer particles from intermingling,
It is desirable to use a particle size and a specific gravity that are similar. The heat transfer particles are not limited to the above-mentioned silica as long as they form a gap that serves as a gas passage when filled and can transfer heat, and ceramics, metal spheres, or the like can also be used. The heat transfer particles can be filled from the state where the top plate is hidden to the position where the spring can contract when the catalyst expands. In the above embodiment, the fuel gas used for the reforming reaction is supplied from above the catalyst layer, but it may be supplied from below.

[0021]

As described above, in the present invention, even if the upper surface of the catalyst layer moves downward due to pulverization of the catalyst, etc., the heat transfer particles in the heat transfer particle layer move downward accordingly. ,
No space is formed between the catalyst layer and the heat transfer particle layer, the catalyst is always held by the heat transfer particles, and the upper end of the catalyst does not tilt.

Further, the heat transfer particle layer heated by the heat from the heating space keeps the temperature of the catalyst layer or heats the fuel gas supplied to the catalyst to raise the temperature of the upper part of the catalyst layer. The decrease is reduced, and the difference in the temperature distribution of the catalyst can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a reformer according to an example of the present invention.

FIG. 2 is a graph showing a temperature distribution of a reformer.

FIG. 3 is a diagram showing a temperature distribution measurement position.

FIG. 4 is a cross-sectional view of a conventional reformer.

FIG. 5 is a diagram for explaining a problem of a conventional reformer.

FIG. 6 is a diagram for explaining a problem of a conventional reformer.

[Explanation of symbols]

 1 Partition Cylinder 2 Inner Cylinder 10 Catalyst Layer 12 Heat Transfer Particle Layer 13 Presser Plate 14 Spring

Front page continuation (72) Inventor Katsuyuki Makihara 2-5-5 Keihan Hondori, Moriguchi Sanyo Electric Co., Ltd.

Claims (4)

[Claims] 1. A first cylinder, a second cylinder provided on the outer periphery of the first cylinder at a predetermined distance from the first cylinder, and a ceiling for closing an upper end opening of the first cylinder. A plate and a heating space surrounded by the top plate and the first cylinder, and the upper end of the second cylinder is extended upward from the top plate position,
A catalyst layer through which the fuel gas used for the reforming reaction passes is provided between the first cylinder and the second cylinder, and the upper surface of the catalyst layer is lower than the top plate. In the tube, the heat transfer particle layer is provided in a state of being stacked on the catalyst layer, the upper surface of the layer of the heat transfer particles is located above the top plate, and further on the heat transfer particle layer. A reforming device characterized in that a catalyst pressing plate is elastically urged. 2. A reforming apparatus comprising: a partition tube, an inner tube provided inside the partition tube, and an outer tube provided outside the partition tube, wherein the inner tube is a top plate. And a heating space is formed by the inner cylinder and the top plate, and the space surrounded by the partition cylinder and the inner cylinder is filled with a catalyst to a position that does not reach the top plate position. Further, the upper part of the catalyst is filled with heat transfer particles above the position of the top plate, and the pressing plate is elastically pressed by the elastic pressing means on the upper part of the heat transfer particles filled as described above. A reformer characterized by: 3. The reformer according to claim 2, wherein the elastic pressing means is a metallic spring. 4. The reformer according to claim 2, wherein the heat transfer particles are at least one kind selected from silica, ceramics, and metals.