JPH0455302A - Hydrocarbon reformer - Google Patents

Abstract

PURPOSE:To obtain the apparatus which is compact and has an excellent thermal efficiency, and is allowed to control the generating quantity of reformed gas to be optional one by joining combustion gases generated in each hydrocarbon reformer in a fire-resisting and heat-insulating hausing and then discharging. CONSTITUTION:The flow passage of combustion gas (A) formed in the clearance between a rising pipe and a inner pipe 5 in each of reformers A-G is opened at the top end side of reaction pipe 2 into the inner part of the housing 1. The combustion gas (C) flowing out of the opening part flows through the space S packed with heat transmitting packing as a common flow passage in the housing 1 while heating each reaction pipe 2, 2,... from the outside of each outer pipe 6, 6,..., and is discharged through an exhaust gas discharge pipe 13. The raw material gas (A) introduced through a raw material gas pipe XI is branched into each raw material gas supplying pipe 11, 11,..., and then flows through each reaction pipe 2, 2,... while being heated with the combustion gas (C) to be reformed, and the reformed gases from each reformed gas taking- out pipe 12, 12,... are joined together in a reformed gas pipe XII to be discharged.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is directed to reforming a raw material gas consisting of hydrocarbons by means of steam reforming to obtain a reformed gas containing hydrogen as a main component. Regarding the reformer, in detail, it is an improved hydrocarbon reformer that can easily adjust the amount of reformed gas generated according to changes in the load of reformed gas, thereby increasing the thermal efficiency of the entire paddy and equipment. The present invention relates to an apparatus, and this apparatus is useful for producing raw material gas for fuel cells, etc.

[Prior Art] As an apparatus for mixing steam with hydrocarbon raw materials such as fuel oil, naphtha, and natural gas, and passing the mixture through a catalyst packed bed to produce reformed gas containing hydrogen as the main component, for example, Showa 53
-78992, 53-79766, 56-90
No. 862, No. 5B-63783, JP-A-1-1559
No. 40, Special Publication No. 57-7538, etc. are known.

These devices have a double concentric tube structure with one end communicating with the other. A reaction tube is filled with a catalyst, and while the reaction tube is heated by a burner, a hydrocarbon raw material is passed through the catalyst packed bed. The aim is to improve thermal efficiency and make the equipment more compact.

For example, FIG. 3 is a schematic longitudinal sectional view illustrating a typical reformer among these, in which 1 is a furnace body, 2 is a reaction tube,
3 is a burner, 4 is a partition cylinder, 5 is an inner pipe, 6 is an outer pipe, 7
is a reforming catalyst, 8 is a filler for promoting heat transfer, 9 is a refractory material, 1
0 is a riser pipe, 11 is a raw material supply pipe, 12 is a reformed gas discharge pipe, 13 is a combustion exhaust gas discharge pipe, 14 is a combustion air supply pipe, and 15 is a fuel supply pipe, and the arrows are explained (^ ) is raw material gas, (B) is reformed gas, (C) is
indicates each residue of combustion gas (or combustion exhaust gas).

As shown in the figure, a double-tubular reaction tube 2 is inserted into a furnace body 1, and a riser tube 10 and a burner 3 are arranged concentrically inside the reaction tube 2. A reforming reaction is carried out by filling a reforming catalyst 7 into the reactor 2 and heating it with combustion gas (C) from a burner 3 while flowing a raw material gas (mixed gas of hydrocarbon gas and steam). That is, the reaction tube 2 has a double tube structure with a partition cylinder 4 inserted between the inner tube 5 and the outer tube 6, and the inner layer side flow path 5a and the outer layer side flow path 6a are communicated with each other at the lower end thereof. Ori,
The raw material gas (A) supplied from the raw material gas supply pipe 11 is
After passing through the catalyst 7-filled portion of the reaction tube 2 and being reformed, it is extracted from the outlet pipe 12 as reformed gas (B). In addition, the combustion gas (C) generated in the burner 3 is transferred to the riser pipe 1
After rising through the inner tube 5, it changes direction upon hitting the refractory material 9, heats the raw material gas (^) from inside the inner tube 5 while descending through the gap between the riser tube 10 and the reaction tube 2, and then heats the raw material gas (^) from the inside of the inner tube 5. The raw material gas (^) is heated from the outside of the outer tube 6 and cooled down, and is then discharged from the combustion exhaust gas discharge tube 13. Therefore, the flow path of the combustion gas (C) may be filled with a filler 8 to improve heat transfer efficiency.

Since such a reformer has a reaction tube having a double tube structure, it has the advantage of high reforming efficiency and thermal efficiency, and the ability to make the apparatus compact.

By the way, in this type of reformer, if the flow paths for the raw material gas (^) and combustion gas (C) are made thicker, the heat transfer efficiency will decrease and the characteristics of the device cannot be effectively utilized, so these flow paths should be configured as narrow as possible. It is advantageous to expand the effective heat transfer area and increase the reforming efficiency and thermal efficiency. However, if these channels are narrowed, the flow rate of the raw material gas cannot be increased much, so there is a natural limit to the processing capacity (ie, the production capacity of the reformed gas). In addition, increasing the inner diameter of the reforming tube may be considered as a means of increasing the processing capacity, but in this case there is a limit in terms of material strength, and it cannot be made extremely large.

Therefore, in order to increase the processing capacity or easily respond to fluctuations in the amount of reformed gas demanded by equipment that requires reformed gas, a reformer was proposed in which multiple page breakers were installed in parallel (for example, in JP-A-58 -124530, Special Publication Showa 62-11608
No., Special Publication No. 63-27972, etc.).

[Problems to be Solved by the Invention] In the above-mentioned reformer with increased processing capacity, ■ Many small-diameter reforming tubes are installed in parallel to increase the flow rate of raw material gas, and all of the gas is handled by one burner. There is a type that heats reforming tubes, a type that allows each group of reforming tubes to be heated with one burner, and a type that heats reforming tubes with individual heating burners as one unit. There is a type in which multiple units are installed side by side.

The above type (2) can be called a multi-tubular reformer, and the type (2) can be called a multi-unit reformer.

In the multi-tube reformer described in (iii) above, the processing capacity can be easily increased by increasing the number of reformer tubes installed, and the reformer tubes can be housed in one furnace, but the burner The spacing between the reforming tubes must be such that the flames do not touch each other.
Compactness of the equipment is not often achieved, and since the processing capacity of this equipment is almost determined by the number of installed reforming pipes, the amount of reformed gas generated must be changed in response to load fluctuations on the reformed gas demand equipment side. It is not suitable for such control.

On the other hand, in the multi-unit reformer mentioned above, each unit has a reformed gas production function, so the total amount of reformed gas generated can be changed arbitrarily by changing the number of operating units as necessary. This makes it possible to easily respond to load fluctuations on the reformed gas demand line equipment side. However, in this reformer, a fairly thick-walled refractory heat insulating furnace, exterior material, etc. must be formed for each unit, making the device as a whole bulky and unable to meet the demand for compactness.

The present invention was made in view of these circumstances, and its purpose is to combine the features of the multi-tubular reformer with the features of the multi-unit reformer, and to provide a compact and excellent thermal efficiency. Moreover, it is an object of the present invention to provide a reformer that can arbitrarily adjust the amount of reformed gas generated in accordance with fluctuations in the amount of reformed gas required by equipment that requires reformed gas.

[Means for Solving the Problems] The structure of the reformer according to the present invention that can solve the above problems is to combine a hydrocarbon reformer with a multi-tube structure each equipped with a combustion burner into a fireproof and heat-insulating housing. The main feature is that a plurality of hydrocarbon reformers are arranged in parallel within the housing, and the combustion gas generated by each hydrocarbon reformer is combined within the housing and then discharged outside the housing.

[Operations and Examples] Hereinafter, the configuration and functions and effects of the present invention will be specifically explained with reference to the drawings of the examples. It is also possible to appropriately change the design and implement it within a range that is compatible with the above, and all of these are included in the technical scope of the present invention.

Fig. 1.2 shows an embodiment of the present invention, Fig. 1 is a schematic longitudinal sectional view and corresponds to the sectional view taken along line I-I in Fig. 2, and Fig. 2 is a schematic cross-sectional view. If − in FIG.
This corresponds to a sectional view taken along line II.

This reformer includes burners 3, 3, 3 and 3, respectively, as shown in the figure.・
Multi-tube structure hydrocarbon reformer A, B, C, equipped with...
D, E, F, and G are arranged in parallel in one fireproof and insulated housing I, and each modified NWANG has an inner pipe 5, an outer pipe 6, and
It is equipped with a reaction tube 2 consisting of a partition inner cylinder 4, a riser tube 10, and the like. and each reaction tube 2.2. Raw material gas supply pipe 11.11. ...and reformed gas outlet pipe 1
2゜12,... are respectively 1 after going out of the housing I.
The raw material gas pipe and the reformed gas pipe are merged into the cutter. On the other hand, the flow path of the combustion gas (C) formed between the riser pipe 10 and the inner pipe 5 in each reforming @A to G is
is opened into the housing I at the tip side of the housing I, and the combustion gas (C) exiting from this opening flows into the housing I! Each reaction tube 2.2. 6.6. ... rises while being heated from the outside, and is extracted from the exhaust gas exhaust pipe 13 to the outside of the system. In this space S, if the gas flow is rectified by a rectifying plate or the like, there is no need to fill it with a heat transfer filler.The raw material gas introduced from the raw material gas Aokari (^)
After branching into the respective raw material gas supply pipes 11, 11, . ) is heated and reformed by the respective reformed gas outlet pipes 12, 12 .
-..., the reformed gas joins Aokari and is extracted and injected.

In this device, each of the plurality of reformers A-G is equipped with a burner 3 and has a reforming ability, and these reformers A-G
The amount of reformed gas generated can be freely changed by changing the number of operating units, the amount of gas introduced into each of the reformers A to G, and the fuel. In addition, the fireproof and insulated furnace and its casing components, which are the bulkiest parts of the multi-unit reformer mentioned above, can be replaced with a single fireproof and insulated housing! It can be done with just one bamboo, and the equipment can be made more compact. Moreover, since the combustion gases (C) discharged from each reformer A to G into the casing I mutually diffuse in the process of rising in the space S, the temperature of the combustion gas generated in each reformer A to G Even if there are different stems, each combustion gas (C) will diffuse and merge in the process of ascending through the space S, and the temperature will be averaged, and the reforming temperature will be uniform as a whole in the device. This makes it possible to obtain a stable modification effect.

In Fig. 1, the raw material gas is directly connected to the raw material gas supply pipe 11.
, 11. ..., and the reformed gas outlet pipe 12,
12. ... is directly merged into the reformed gas pipe line,
Raw material gas supply pipes tt, ii, . . . and reformed gas outlet pipes 12, 12. A flow path opening/closing mechanism such as a solenoid valve is attached to each of the reformers A to G, and the raw material gas (^) is supplied to only the operating reformers A to G, and the reformed gas (C) is led out. It is preferable to obtain it. Furthermore, if the flow passage opening/closing mechanism is made to be able to adjust the flow rate and the combustion supply amount to each burner 3 can be controlled, the raw material gas supply amount can be adjusted to accommodate changes in the reformed gas demand. Therefore, even if the required amount of reformed gas fluctuates significantly, it is possible to cope with it without increasing or decreasing the number of operating reformers.

Although Fig. 1.2 shows an example in which seven reformers A to G are arranged in parallel in a cylindrical housing I, the shape of the housing I is not limited to a cylindrical shape, but may be any shape such as a rectangular cylindrical shape. The number of reformers installed in parallel also depends on the processing capacity of each reformer, the scale of the reformed gas demand equipment, the degree of expected fluctuation in the reformed gas demand, etc. You should consider this and decide accordingly.

[Effects of the Invention] The present invention is configured as described above, and takes advantage of the characteristics of both the multi-tubular reformer and the multi-unit reformer, ensuring compactness and excellent thermal efficiency, and improving the reforming efficiency. It is now possible to provide a reformer that can freely control the amount of reformed gas produced in accordance with fluctuations in the amount of gas required. Furthermore, in the device of the present invention, the inside of the housing forms a common (7) combustion gas flow path for the plurality of reformers, and the combustion gases merge and diffuse into each other in the common flow path, so that the temperature is averaged. As a result, the reforming reaction temperature of the entire apparatus is stabilized, and operational stability is improved.

[Brief explanation of drawings]

FIG. 1 is a schematic vertical cross-sectional view illustrating a reforming apparatus of the present invention, FIG. 2 is a schematic cross-sectional view of the same apparatus, and FIG. 3 is a schematic vertical cross-sectional explanatory view illustrating a conventional reforming apparatus. 1... Furnace body 2... Reaction tube 3... Burner 4... Partition cylinder 5... Inner tube
6...Outer tube 7...Reforming catalyst 8
... Filler for heat transfer promotion 9 ... Refractory material 11 ... Raw material gas supply pipe 13 ... Combustion exhaust gas discharge pipe 15 ... Fuel supply pipe ■ ... Fireproof insulation housing A-G ...・Reformer lO...Riser pipe 12...Reformed gas outlet pipe 14...Combustion air supply pipe Fig. 1

Claims (1)

[Claims] A plurality of hydrocarbon reformers each having a multi-tubular structure each equipped with a combustion burner are installed in parallel in a fireproof and insulated housing, and the combustion gases generated in each hydrocarbon reformer are combined within the housing. 1. A hydrocarbon reforming device characterized in that the hydrocarbon reforming device is configured to discharge the hydrocarbons to the outside of the housing.