JPS6183601A - Reforming apparatus - Google Patents

Abstract

PURPOSE:To uniformize the temperature distribution in the reforming tube of an apparatus for the steam reforming of raw gas and to increase the efficiency of the reforming reaction, by improving the supporting structure of the reforming tube. CONSTITUTION:The first arm piece 23 having a hollow part 23a at the bottom face is fixed to the outer circumference of the disk-shaped tubular plate 15 supporting the reforming tube, and the second arm piece 24 having a hollow part 24a at the top face is attached to the inner wall of the reforming vessel 1 at a position corresponding to the first arm piece 23. The first arm piece 23 is combined slidably with the second arm piece 24 facing the hollow parts 23a and 24a each other with a sliding piece 25 therebetween. The sliding piece 25 is arranged in a manner that the center of the piece coincides with the meridian 26 from the center 21 of the reforming vessel 1, and the arm pieces 23 and 24 are made slidably only along the direction of meridian 26. The slidable fixing member having the above structure is attached to >=2 parts on the outer circumference of the tubular plate 15 except for the positions on the same line. The tubular plate 15 is fixed and supported by the slidable fixing members. The sliding piece 25 is made of a heat-insulating material having high hardness, e.g. ceramic, alumina, etc.

Description

[Detailed Description of the Invention] (Technical Field of the Invention) The present invention relates to a reforming method that steam-reforms raw material gas to obtain reformed gas by flowing high-temperature gas outside the reforming tube and heating the reforming tube. The present invention relates to a reforming device, and particularly to a reforming device that improves reforming efficiency by improving the support structure of reforming tubes.

[Technical Background of the Invention] FIG. 3 is a sectional view showing an example of the configuration of a conventionally used double-tube reformer.

In the figure, 1 is a reformer container, and 2 is a reforming tube with an annular cross section that is sealed at one end (upper end) and has a reforming catalyst layer 3 between the inner tube and the outer pipe. A plurality of such reforming tubes 2 are arranged inside the reformer container 1 in a plurality of layers. Further, combustion air and combustion gas are introduced into the combustion burner nozzle 6 from the combustion air inlet pipe 4 and the combustion gas inlet pipe 5 attached to the upper part of the reformer container 1, respectively, and are combusted in the combustion chamber 7. The reforming tube 2 is heated by passing through the heat transfer packed bed 9 supported on the perforated plate 8 on the outside of the reforming tube 2, and then this high temperature combustion gas is transferred to the exhaust gas outlet. It is discharged from the pipe 10 to the outside of the reformer container 1. On the other hand, raw material gas is introduced into the reforming catalyst layer 3 in the reforming tube 2 through the raw material gas inlet pipe 11 together with water vapor, and this is heated in the reforming catalyst layer 3 to generate reformed gas. The reforming gas is reversed at the top 12 of the reforming tube and descends through the return path 13, applying heat to the reforming catalyst layer 3 to lower its temperature, and then being discharged from the reformed gas outlet pipe 14 to the outside of the reformer container 1. Ru.

Further, the other ends (lower ends) of the plurality of reforming tubes 2 are attached to and supported by a tube plate 15, and the tube plate 15 in parentheses is supported on the reformer container 1 through a heat insulating material 16. It is attached to a stand 17. Further, a heat insulating layer 18 is provided between the reformer container 1 and the heat transfer packed bed 9, which is a passage for the high temperature combustion gas, to reduce heat escape. Here, various materials such as brick, ceramic wool, glass wool, etc. may be used as the heat insulating material for the heat insulating layer 18, but especially when the reformer is started and stopped frequently, However, bricks cannot be used because they tend to crack, so ceramic wool is mainly used. Note that 19 is a packed bed cylinder provided around the heat transfer packed bed 9.

[Problems with Background Art] By the way, in the reformer having such a configuration, since several reforming tubes 2 are attached to and supported by the tube plate 15, the temperature of the reformed gas is 500 to 600°C. C., so when the reformer is operated, the temperature of the tube sheet 15 rises to approximately this temperature, and the diameter of the outer periphery of the tube sheet 15 increases due to thermal expansion. However, in contrast, the temperature of the reformer vessel 1 is 70 to 80°C, and the thermal expansion of the inner diameter is extremely small. Therefore, the heat insulating material 16 placed on the support stand 17
The center position of the tube plate 15 and the tube plate 15 above it will be shifted by 5 to 20 mm due to thermal expansion. If the center position of the tube plate 15 with respect to the reformer container 1 shifts, the temperature distribution between the plurality of reforming tubes 2 will become uneven. That is, if the tube plate 15 were to shift to the left in the figure, all of the plurality of reforming tubes 2 would move to the left, so even though the reforming tubes 2 are uniformly arranged in the combustion chamber 7, First, due to these shifts to the left, the width of the heat transfer packed layer 9 around the leftmost reforming tube 2 becomes narrower, and the width of the heat transfer packed layer 9 around the rightmost reforming tube 2 becomes wider. , this causes the left reforming pipe 2
The temperature of the reforming tube 2 on the right side decreases, and conversely, the temperature of the right reforming tube 2 increases.

As a result, the temperature difference between the left and right reforming tubes 2 increases, and the temperature distribution in each reforming tube 2 becomes non-uniform, making it impossible to carry out a uniform reforming reaction.

[Purpose of the Invention] The present invention has been made to solve the above-mentioned problems, and its purpose is to eliminate the shift in the center position of the reforming tubes and to adjust the shape of each reforming tube in a manner that copes with thermal expansion. It is an object of the present invention to provide a reforming device capable of uniformly distributing temperature and carrying out an extremely efficient reforming reaction.

[Summary of the Invention 1 In order to achieve the above object, the present invention provides a plurality of reforming tubes each having an annular cross section, one end of which is sealed and a reforming catalyst layer provided between the inner tube and the outer tube. The reformer is disposed inside the reformer vessel, and high-temperature gas flows in from one end of the reformer tube and flows out from the other end through a heat transfer layer provided outside the reformer tube. In a reformer configured to allow inflow from the other end of the reforming tube through the reforming catalyst layer and outflow from the other end through the inner tube from one end thereof, a disc-shaped disk to which each of the above-mentioned reforming tubes is attached is provided. First arm pieces are attached and fixed at multiple locations on the outer circumferential surface of the tube sheet except on the same line, and second arm pieces are attached to the inner wall surface of the reformer container corresponding to the first arm pieces for winter use. The arm pieces are each attached and fixed, and the first arm piece and the second arm piece are slidably put together via a sliding piece, and the first arm piece and the second arm piece are configured to be slidable together. It is characterized in that the pieces are relatively slidable only in the meridian direction from the center of the reformer vessel.

[Embodiments of the invention] An embodiment of the present invention shown in the drawings will be described below.

1 and 2 show an example of the support structure of the reforming tube in the reformer of the present invention. FIG. 1 is a plan view taken in the direction of the arrow ■ in FIG. This is a cross-sectional view taken along the line ■--■ in FIG. 1, and the same parts as in FIG. 3 are denoted by the same reference numerals.

In the figure, reference numeral 15 denotes a disk-shaped tube plate formed with an outer circumference 22 having a radius R with respect to the center 21 of the reformer container 1, and a first tube plate 15 having an outer circumference 22 with a radius R on the outer circumference. The arm piece 23 is fixedly attached. On the other hand, the first arm piece 2
A second arm piece 24 having a cap 24a on the upper surface side is fixedly attached to the inner wall surface of the reformer container 1 corresponding to No. 3, and these first arm pieces 23 and 2 arm piece 2
4 are combined so that the respective housing parts 23a and 24a are opposed to each other via the sliding piece 25, so that they can freely slide. Here, the center portion of the sliding piece 25 is connected to the reformer container 1.
In other words, the first arm piece 23 and the second arm piece 24 are arranged to be relatively slidable only in the direction of the meridian plane 26 from the center 21 of the arm. Further, the first arm piece 23 and the second arm piece 24 are attached using bolts and nuts 27 so that they do not separate from each other due to vibrations such as earthquakes.
This is to prevent lifting.

Roughly speaking, 23b and 24b are sliding surfaces of the first arm piece 23 and the second arm piece 24, respectively.
4b are surfaces equidistant from the meridian plane 26 and parallel to the meridian plane 26, respectively. In reality, the sliding mounting having the above configuration is performed by arranging the body at two or more locations on the outer circumferential surface of the tube sheet 15, excluding those on the same line, so that the tube sheet 15 is supported during installation. There is. In the above, the sliding piece 25 is made of ceramic or zirconia.

Use a hard insulating material such as alumina.

In the reforming device having such a configuration, the sliding attachment formed by slidably combining the first arm piece 23 and the second arm piece 24 allows the body to be attached to the outer peripheral surface of the tube plate 15 except on the same line. Since the tube sheet 15 is disposed at 21 or more locations, the tube sheet 15 does not become misaligned from the center 21 of the reformer vessel 1 as in the conventional case, and the thermal expansion ΔR of the tube sheet 15 in the radial direction You can freely follow the target. As a result, it is possible to eliminate misalignment between the plurality of reforming tubes 2, reduce the temperature difference between them, eliminate uneven temperature distribution in each reforming tube 2, and perform a uniform reforming reaction. . Furthermore, the sliding piece 25 is made of ceramic.

By using a hard heat insulating material such as zirconia or alumina, less heat is required to be radiated to the outside, and the reforming efficiency can be further increased.

In the above embodiment, a highly hard heat insulating material is used as the sliding piece 25, but the present invention is not limited to this, and it is also possible to use a sliding piece made of a metal plate.

[Effects of the Invention] As explained above, according to the present invention, areas on the same line are excluded from the outer peripheral surface of the disk-shaped tube sheet to which a plurality of reforming tubes are attached. ! The first arm pieces are attached and fixed at several places, and the second arm pieces are attached and fixed to the inner wall surface of the reformer container corresponding to the arm pieces of the famous confectionery 1. The first arm piece and the second arm piece are combined with each other via a sliding piece so as to be slidable, and the first arm piece and the second arm piece are relatively connected to each other through a meridian from the center of the reformer container. Since only one movement is possible in the direction of the surface, it eliminates deviations in the center position of the reforming tube, and by dealing with thermal expansion, the temperature distribution in each reforming tube is uniform, resulting in an extremely efficient reforming reaction. It is possible to provide a reforming device that can perform the following.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 are configuration diagrams showing one embodiment of the present invention,
FIG. 3 is a sectional view showing the configuration of a conventional reforming device. DESCRIPTION OF SYMBOLS 1... Reformer container, 2... Reforming tube, 3... Reforming catalyst layer, 4... Combustion air inlet pipe, 5... Combustion gas inlet pipe, 6... Combustion burner nozzle , 7... combustion chamber, 8.
... Perforated plate, 9... Heat transfer packed bed, 10... Exhaust gas outlet pipe, 11... Raw material gas inlet pipe, 13... Return bath, 14... Reformed gas outlet pipe, 15...tube plate, 1
6... Heat insulating material, 18... Heat insulating layer, 19... Filled bed cylinder, 21... Center of reformer container, 22... Outer periphery of tube plate, 23.24... Arm piece, 23a , 24a... shell part, 23b, 24b... sliding surface, 25... sliding piece, 2
6... Meridian plane, 27... Mounted with bolts and nuts. Applicant's agent Patent attorney Takehiko Suzue Figure 1

Claims (2)

[Claims] (1) A plurality of reforming tubes each having an annular cross section, one end of which is sealed and a reforming catalyst layer provided between the inner tube and the outer tube, are arranged inside the reformer container, and high-temperature gas flows into one end of the reforming tube and flows out from the other end through a heat transfer packed layer provided on the outside, and raw material gas flows in from the other end of the reforming tube through a reforming catalyst layer. In a reformer configured such that the reformer passes through an inner pipe from one end and flows out from the other end, a plurality of locations on the outer peripheral surface of a disc-shaped tube plate to which each of the reforming pipes is attached, excluding those on the same line. At the same time, a first arm piece is attached and fixed to the inner wall surface of the reformer container corresponding to each of the first arm pieces, and a second arm piece is attached and fixed to the inner wall surface of the reformer container. two arm pieces are combined via a sliding piece so as to be slidable, and the first arm piece and the second arm piece are relative to each other in the direction of the meridian plane from the center of the reformer container. A reforming device characterized by being able to slide only on the surface. (2) The reforming device according to claim (1), wherein a highly hard insulating material such as ceramic, zirconia, alumina, or a metal plate is used as the sliding piece.