JPH11548A - Steam reformer and catalyst exchange method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable to exchange the catalyst filled in a reaction tube without releasing a flange of a container and also without cutting the reaction tube. SOLUTION: Relating to a steam reformer 1 provided with plural numbers of reaction tubes 9 filled with the catalyst 27 in the inside, this reformer 1 is provided with a catalyst discharge tube 35 connected to the reaction tube 9 from the outside of the steam reformer 1, an air communicative tube 37 of which one end is faced to a position capable of inflow of air from the bottom of the reaction tube 9 and of which another end is opened to the outside of the steam reformer 1, and a catalyst feed tube 39 connected to the upper part of the reaction tube 9 from the outside of the steam reformer 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a steam reformer for obtaining hydrogen from natural gas or the like by reacting with steam, and more particularly to an exchange structure for a catalyst filled in a reaction tube inside a steam reformer. It relates to an exchange method.

[0002]

2. Description of the Related Art The internal structure of a conventional steam reformer is shown in FIG. 3 and will be described with reference to the drawings. The steam reformer 1 has a structure in which the container 3 and the upper mirror 5 are connected by a flange 7 outside. A plurality of reaction tubes 9 are arranged in the vessel 3, and the reaction tubes 9 are supported by a tube plate 11. The bottom of the reaction tube 9 is closed by a perforated plate 13 having a plurality of holes. A central pipe 15 penetrates the center of the perforated plate 13, an upper part of the central pipe 15 reaches an upper part of the reaction tube 9, and a lower part of the central pipe 15 is connected to a reforming gas outlet nozzle 17. It is connected to the gas outlet pipe 19. Further, in addition to the reformed gas outlet nozzle 17, a raw material inlet nozzle 21, a heated gas inlet nozzle 23, and a heated gas outlet nozzle 25 are connected to the container 3. Further, inside the reaction tube 9, a spherical catalyst 2 is formed in a space formed by the central pipe 15 and the perforated plate 13.
7 are filled. In the steam reformer 1 configured as described above, raw gases such as natural gas and steam are supplied into the vessel 3 from the raw gas inlet nozzle 21, and the catalyst layer 27 in the reaction tube 9 is supplied from the perforated plate 13. Rise. Here, the reformed gas is inverted as a reformed gas in the upper portion of the reaction tube 9, flows downward in the central pipe 15, passes through the reformed gas outlet pipe 19, and passes through the reformed gas outlet nozzle 17 to the container 3. It is discharged outside. On the other hand, the heated gas is supplied into the vessel 3 from the heated gas inlet nozzle 23 and is discharged from the vessel 3 from the heated gas outlet nozzle 25 while heating the outer surface of the reaction tube 9. However, if the operation is continued as described above, the catalyst 27 changes over time and needs to be replaced after a certain period of time. Therefore, in the conventional catalyst exchange, after separating a pipe or the like (not shown) connected to the heating gas inlet nozzle 23 from the outside of the vessel 3, the flange 7 is opened, and the tip of the internal reaction tube 9 is cut. doing. Thereafter, a vacuum suction hose (not shown) is inserted into the reaction tube 9 having an open top, the deteriorated catalyst is taken out, and a new catalyst is filled with a funnel (not shown).
The cutting part 10 is connected again by welding.

[0003]

In the above prior art,
In order to replace the catalyst by cutting off the tip of the reaction tube, it is necessary to open the flange of the vessel. Furthermore, with the opening of the flange, it becomes necessary to open the heating gas side system,
Work becomes large. Furthermore, even if the flange is opened, if the tip of the reaction tube is cut, the work of cutting the plurality of reaction tubes one by one is not easy, and the work is still complicated.

Accordingly, an object of the present invention is to provide a steam reformer and a catalyst capable of replacing a catalyst filled in a reaction tube without opening a flange of the vessel and cutting the reaction tube. It is to provide an exchange method.

[0005]

According to the present invention, there is provided a steam reformer having a plurality of reaction tubes filled with a catalyst therein, comprising: a catalyst discharge tube connected to the reaction tube from outside the steam reformer; Is directed to a position where air can flow in from the bottom of the reaction tube, the other end is open to the outside of the steam reformer, an air flow tube, and the top of the reaction tube from outside the steam reformer. It is provided with a connected catalyst supply pipe. Further, in the method for replacing a catalyst of a steam reformer having a plurality of reaction tubes filled with a catalyst therein, a catalyst discharge tube connected to the reaction tube from outside the steam reformer, and one end from a bottom of the reaction tube. An air flow pipe whose other end is open to the outside of the steam reformer, and a catalyst supply pipe connected from the outside of the steam reformer to the upper portion of the reaction tube. When the catalyst is exchanged, the catalyst in the reaction tube is extracted by flowing air from the catalyst supply tube through the reaction tube to the catalyst discharge tube, and then the air flow is passed through the reaction tube from the catalyst supply tube. This is a catalyst replacement method in which a fresh catalyst is filled in the reaction tube by flowing air through the tube.

In these cases, the deteriorated catalyst inside the reaction tube can be taken out by flowing air from the catalyst supply tube to the catalyst discharge tube through the reaction tube. By allowing air to flow through the flow tube, it becomes possible to supply the catalyst to the inside of the reaction tube, and the inside of the reaction tube can be filled with new catalyst.

[0007]

FIG. 1 is a block diagram of a steam reformer according to the present invention, which will be described in detail with reference to this drawing. That is, the steam reformer 1 has a structure in which a cylindrical container 3 and an upper mirror 5 are integrally formed, and inside the container 3, a plurality of cylindrical reaction tubes 9 each having a cap 29 attached to the upper part are provided. Board 1
1, a heating gas flow part 31 is provided at an upper part of the vessel and a raw gas flow part 3 is provided at a lower part of the vessel with the tube sheet 11 as a boundary.
No. 3 is formed. A catalyst discharge pipe 35 connected from the outside of the vessel 3 to the lower part of the reaction tube 9 is arranged, and the bottom of the reaction tube 9 is closed by a perforated plate 13 having a plurality of holes. . A cylindrical central pipe 15 penetrates through the center of the perforated plate 13, and the upper portion of the central pipe 15 reaches a position almost above the reaction tube 9. On the other hand, a lower portion of the central pipe 15 is connected to a reformed gas outlet pipe 19 which is opened to the outside of the container 3 via a reformed gas outlet nozzle 17. Further, in addition to the reformed gas outlet nozzle 17, the container 3 has a raw material inlet nozzle 21 opened to the raw material gas flow portion 33 inside the container 3, and a position at which one end is capable of flowing air from the bottom of the reaction tube 9. And an air circulation pipe 37 whose other end is open to the outside of the container 3 is arranged. Further, a catalyst supply pipe 39 that penetrates the central pipe 15 from the outside of the vessel 3 through the raw material gas flow part 33, rises inside the central pipe 15, and reaches the inside of the reaction pipe 9 from the tip of the central pipe 15 Are arranged, and a filling ring 63 is formed at the tip thereof. A heating gas inlet nozzle 23 opened to the heating gas passage 31 in the container 3 is connected to the upper mirror 5.
A heating gas outlet nozzle 25 is connected to a lower portion of the nozzle 1. Further, inside the reaction tube 9, a space formed by the central pipe 15 and the perforated plate 13 is filled with a spherical catalyst 27. Note that the cylindrical container 3 and the upper mirror 5 are not integrally formed, but may be a structure connected by a flange 7 or the like as in the conventional steam reformer 1.

Next, as shown in FIG. 2, a catalyst exchange device attached to the steam reformer will be described. That is,
The catalyst supply pipe 39 of the steam reformer 1 is connected to a supply line 43 having a supply valve 41 in the middle, and the other end of the supply line 43 is connected to a catalyst container 45. Also,
The catalyst discharge pipe 35 is connected to a discharge line 49 having a discharge valve 47 on the way, and the other end of the discharge line 49 is connected to a catalyst discharge container 51. Further, the air flow pipe 21 is connected to an air line 55 having an air valve 53 on the way, and the air line 55 is connected to a discharge line 49. The catalyst discharge container 51 is connected to the line 5
7 is connected to the filter 59 and the blower 61.

The operation of the steam reformer 1 having the above configuration,
In particular, transfer (replacement) of the catalyst 27 in the reaction tube 9 will be described. If the steam reformer 1 is operated for a long time, the catalyst in the reaction tube 9 will deteriorate, and it is necessary to take out the deteriorated catalyst and replace it with a new catalyst in order to operate the plant safely and efficiently. In order to discharge the deteriorated catalyst in the reaction tube 9, the air valve 53 is closed, the supply valve 41 and the discharge valve 47 are closed.
Open. Here, by operating the blower 61, air flows through the supply line 43, the reaction tube 9, and the discharge tube 49, and together with the air, the deteriorated catalyst (not shown) also passes through the discharge line 49, It is discharged to the discharge container 51. The same applies to the case where a plurality of reaction tubes 9 exist. After exhausting all the deteriorated catalyst in the reaction tube 9,
This time, the discharge valve 47 is closed and the air valve 53 is opened. By operating the blower 61, the supply line 43, the reaction tube 9
Then, air flows through the air line 55 and a new catalyst (not shown) is supplied from the catalyst container 45 to the supply line 43.
And is deposited in the reaction tube 9 by the filling ring 63 in a well-balanced manner. By this operation, the catalyst in the reaction tube 9 can be exchanged.

[0010]

According to the present invention, the catalyst filled in the reaction tube can be exchanged without opening the flange of the vessel and cutting the reaction tube.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a steam reformer according to the present invention.

FIG. 2 is a configuration diagram of a steam reformer according to the present invention and a catalyst exchange device attached thereto.

FIG. 3 is a configuration diagram of a conventional steam reformer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Steam reformer 9 Reaction tube 27 Catalyst (layer) 35 Catalyst discharge tube 37 Air circulation tube 39 Catalyst supply tube

Claims (2)

[Claims] 1. A steam reformer having a plurality of reaction tubes filled with a catalyst therein, wherein a catalyst discharge tube connected to the reaction tube from the outside of the steam reformer and one end of which is connected to a bottom of the reaction tube. An air flow pipe that is directed to a position where air can flow in and has the other end opened to the outside of the steam reformer, and a catalyst supply pipe connected to the upper part of the reaction tube from outside the steam reformer. A steam reformer, characterized in that: 2. A catalyst exchange method for a steam reformer having a plurality of reaction tubes filled with a catalyst therein, wherein a catalyst discharge tube connected to the reaction tube from outside of the steam reformer, and one end of the reaction tube. An air flow pipe whose other end is open to the outside of the steam reformer, and a catalyst connected to the top of the reaction tube from outside of the steam reformer. A supply pipe is provided, and when the catalyst is exchanged, the catalyst in the reaction pipe is extracted by flowing air from the catalyst supply pipe through the reaction pipe to the catalyst discharge pipe, and then the catalyst is supplied from the catalyst supply pipe through the reaction pipe. A catalyst replacement method, characterized in that a fresh catalyst is filled in the reaction tube by flowing air through the air flow tube.