JP2003306311A - Autothermal reforming device and autothermal reforming method using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an apparatus and a reforming method having high reforming efficiency that provide a reformed gas having high hydrogen content by suppressing the occurrence of heat spots to level the temperature distribution in the lateral direction of a reactor (in a plane orthogonal to the flow of a raw material gas) in addition to the leveling of the temperature distribution in the longitudinal direction of a reactor (the direction of the flow of a raw material gas), to reduce the deterioration of a catalyst and to suppress the slippage of the raw material gas. <P>SOLUTION: The autothermal reforming device 10 for producing a reformed gas by supplying a gas containing a reforming raw material, steam and oxygen from the inlet side 2 of a catalyst layer is provided with a low-activity region 5, between catalyst layers 1a and 1b, that has no oxidation activity or less oxidation activity than other regions. At least part of the oxygen required for the reaction is supplied from an oxygen supplying port 3 to the low-activity region 5. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an autothermal reforming reformer for converting hydrocarbons into a mixed gas containing carbon monoxide and hydrogen by an autothermal reforming reaction.

[0002]

2. Description of the Related Art Steam reforming (SR) and auto thermal reforming (AT) are used as techniques for reforming reforming raw materials such as hydrocarbons into synthesis gas and hydrogen.
Various methods such as R) and partial oxidation (POX) have been developed.

Of these, many technologies have already been put to practical use for SR, but since it is a reaction involving a relatively large amount of heat absorption, the load on the heat supply system such as a heat exchanger is large and it takes time to start. Is inferior in terms of.

On the other hand, contrary to SR, POX has a very short start-up time, but it is difficult to control because of large heat generation due to oxidation, and there are problems such as suppression of soot generation.

On the other hand, the ATR supplies a reforming raw material such as hydrocarbon, an oxidizing agent such as air, and steam to a reformer having a catalyst layer to oxidize a part of the raw material. This is a technique for balancing the reaction heat by advancing SR by the heat generated at this time. Since it has a relatively short start-up time and is easy to control, it has been particularly noted in recent years as a hydrogen production method for fuel cells. There is.

[0006]

The oxidation reaction has a higher reaction rate than the reforming reaction. When the reforming source gas, steam and oxygen are supplied all at once from the upstream of the ATR reformer, a temperature peak first appears near the inlet, as shown in FIG. If this temperature peak is too high, the catalyst deteriorates quickly, and it becomes necessary to use an expensive material for the reaction tube in order to withstand high temperatures. On the other hand, on the reformer outlet side of the catalyst layer, the oxidation reaction is substantially completed, and the SR reaction becomes dominant, so that the temperature drops and the raw material slip that is discharged without the raw material reacts. It is generated or a reformed gas having a relatively low hydrogen concentration due to chemical equilibrium (comparatively high methane concentration) is generated. Therefore, it is desired to increase the outlet temperature while suppressing the peak temperature.

In Japanese Unexamined Patent Publication No. 09-315801, as shown in FIG. 6, steam and fuel gas are supplied to a catalyst layer 90 from a fuel supply passage 79, and oxygen is supplied separately from air supply passages 75 and 82. It is described to do. As a result, the maximum temperature could be lowered as shown in FIG. Further, as shown in FIG. 8, it is also described that steam and fuel gas are supplied from the fuel supply passage 79, and oxygen is divided into a large number and supplied from the air supply passage 83.

However, according to the study by the present inventor, as shown in FIG. 9, the catalyst layer 21, the gas supply port 22, the oxygen supply port 2
3, the reaction device having an outlet 24, hydrocarbon compounds,
When the gas containing a part of water vapor and oxygen was supplied from the gas supply port 22 and the remaining gas containing oxygen was supplied from the oxygen supply port 23, the oxygen was divided and supplied. A heat spot (local heat generation point) 25 was generated on the downstream side. For this reason, in addition to the local deterioration of the catalyst, there is a problem that the heat of partial oxidation is not effectively utilized because the heat is largely nonuniform when viewed in the cross-sectional direction of the reactor.

Further, as shown in FIG. 10, the oxygen supply port 2
Even when No. 5 was extended and the oxygen-containing gas was supplied near the center of the catalyst layer 21, the generation of heat spots was similarly observed.

The present invention has been made in order to solve such a problem. By suppressing the generation of heat spots, in addition to making the temperature distribution in the reactor length direction (flow direction of the raw material gas) uniform, The temperature distribution in the lateral direction of the reactor (in the plane orthogonal to the flow of the raw material gas) is made uniform, the deterioration of the catalyst is reduced, the slip of the raw material gas is suppressed, and the reformed gas with a high hydrogen content is produced. An object of the present invention is to provide an apparatus and a reforming method having high reforming efficiency.

[0011]

The present invention relates to the following items.

1. In an auto thermal reforming reformer that includes a catalyst layer and supplies a reforming raw material, a gas containing steam and oxygen from the inlet side of the catalyst layer to produce a reformed gas, is provided in the middle of the catalyst layer, Autothermal reforming further comprising a low activity region having no oxidative activity or a lower oxidative activity than other regions, and an oxygen supply port supplying at least a part of oxygen necessary for the reaction to this low activity region. Reformer.

2. The low activity region is a layer filled with a filler having no oxidation activity or having a lower oxidation activity than other regions. The described autothermal reforming reformer.

3. The filler is a ceramic ball,
2. The above-mentioned item selected from the group consisting of ceramic pellets, ceramic foams and ceramic rings. The described autothermal reforming reformer.

4. The low activity region is provided only in one place in the catalyst layer, and the low activity region is formed in the above 1-3. 5. The auto thermal reforming reformer according to any one of 1.

5. The ratio of (thickness of low activity region) :( thickness of catalyst layer) is in the range of 1: 3 to 1:50
4. 5. The auto thermal reforming reformer according to any one of 1.

6. The low activity region is provided only at one location in the catalyst layer, and the ratio of (thickness of catalyst layer before the low activity region) :( thickness of catalyst layer after the low activity region) is 0. 5. The range of 5: 8.5 to 8: 1 above.
The described autothermal reforming reformer.

7. The ratio of (amount of oxygen supplied from the inlet): (amount of oxygen supplied from the low active region) is 3: 7 to 9: 1.
Satisfying the above conditions 1 to 6. 5. The auto thermal reforming reformer according to any one of 1.

8. An inlet-side oxygen introducing passage for supplying oxygen to the inlet side, and a low active area oxygen introducing passage for supplying oxygen to at least one low active area,
(Opening cross-sectional area of outlet of inlet side oxygen introduction passage): (Opening cross-sectional area of outlet of low active region oxygen introduction passage) is in the range of 3: 7 to 9: 1. 5. The auto thermal reforming reformer according to any one of 1.

9. In an auto thermal reforming reformer that includes a catalyst layer and supplies a reforming gas by supplying a reforming raw material, steam and oxygen from the inlet side of the catalyst layer, the oxygen is supplied to the inlet side. It has an inlet side oxygen introduction passage and at least one intermediate region oxygen introduction passage for supplying oxygen to the middle of the catalyst layer, (opening cross-sectional area of the outlet of the inlet side oxygen introduction passage): (intermediate region oxygen introduction The autothermal reforming reformer whose opening cross-sectional area at the exit of the passage is in the range of 3: 7 to 9: 1.

10. 1 to 9 above. Using the autothermal reforming reformer according to any one of the above, a reforming raw material and steam from the inlet side of the catalyst layer, and a gas containing a part of the required oxygen amount are supplied, and it is necessary from the middle of the catalyst layer. An autothermal reforming method for producing a reformed gas by supplying a gas containing a sufficient amount of remaining oxygen.

11. 1 to 9 above. Using the autothermal reforming reformer according to any one of the above, a reforming raw material and steam from the inlet side of the catalyst layer, and a gas containing a part of the required oxygen amount are supplied, and it is necessary from the middle of the catalyst layer. An auto-thermal reforming method in which a reformed gas is produced at a catalyst layer temperature of 600 ° C. or higher at the reformer outlet by supplying a gas containing a sufficient amount of oxygen.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION As a reforming raw material, any material containing carbon and hydrogen and capable of causing an oxidation reaction by oxygen and a steam reforming reaction by steam can be used. Methanol, ethanol, dimethyl ether, city gas, LPG (liquefied petroleum gas), gasoline, kerosene, etc. can be mentioned as examples that can be inexpensively obtained for industrial or consumer use.

Further, the above raw materials include hydrogen, water, carbon dioxide,
A raw material containing carbon monoxide, oxygen, etc. can also be used. For example, when hydrodesulfurization is performed as a pretreatment of the raw material, the residual hydrogen used in the reaction can be mixed with the raw material without being particularly separated.

On the other hand, the sulfur concentration in the raw material is desirably as low as possible because it has the effect of deactivating the reforming catalyst, and is preferably 50 mass ppm or less, more preferably 20 mass ppm or less. Therefore, if necessary, the raw material can be desulfurized in advance.

The sulfur concentration in the raw material to be subjected to the desulfurization step is not particularly limited, and any raw material having a sulfur concentration such that it can be converted to the above sulfur concentration in the desulfurization step can be used.

The desulfurization method is also not particularly limited, but an example is a method in which hydrodesulfurization is carried out in the presence of a suitable catalyst and hydrogen and the produced hydrogen sulfide is absorbed in zinc oxide or the like. In this case, examples of catalysts that can be used include catalysts containing nickel-molybdenum, cobalt-molybdenum, or the like. On the other hand, if necessary, a method of sorbing a sulfur content in the presence of hydrogen in the presence of an appropriate sorbent can also be adopted. As sorbents that can be used in this case, Japanese Patent Nos. 2654515 and 26
Examples thereof include a sorbent containing copper-zinc as a main component or a sorbent containing nickel-zinc as a main component as disclosed in Japanese Patent No. 88749.

The method for carrying out the desulfurization step is not particularly limited, either.
It may be carried out by a desulfurization process installed immediately before the autothermal reforming reactor according to the present invention, or a raw material treated in an independent desulfurization process may be used.

Oxygen is usually added to the reaction raw material in an amount that can generate a heat quantity capable of balancing the endothermic reaction of SR, but the addition amount is appropriately determined in relation to heat loss and external heating installed as necessary. . The amount is preferably 0.05 to 1, as a ratio (oxygen / carbon ratio) of the number of moles of oxygen molecules supplied to the ATR reaction region to the number of moles of carbon atoms contained in the reforming raw material supplied to the ATR reaction region. More preferably 0.1 to 0.75, even more preferably 0.2 to
It is preferably 0.6. When the oxygen / carbon ratio is smaller than the above range, a small amount of heat is generated and a large amount of heat needs to be supplied from the outside, which is disadvantageous in that the situation is substantially the same as SR. On the other hand, when the oxygen / carbon ratio is larger than the above range, heat generation becomes large and it is difficult to balance heat, and it is disadvantageous in that hydrogen and carbon monoxide are burned and consumed by oxygen and the modified gas yield is reduced. is there.

The oxygen may be pure oxygen, but those diluted with other gas can also be used suitably, such as water vapor,
It may contain carbon dioxide, carbon monoxide, argon, nitrogen, etc. For example, from the viewpoint of easy availability, air, oxygen-enriched air, etc. are preferably used as a gas containing oxygen.

The amount of steam introduced into the reaction system depends on the ATR
It is defined as the ratio of the number of moles of water molecules supplied to the ATR reaction region to the number of moles of carbon atoms contained in the reforming raw material supplied to the reaction region (steam / carbon ratio), and this value is preferably 0.3 to 10 , More preferably 0.5 to 5,
More preferably, it is 1-3. If this value is smaller than the above range, coke tends to precipitate on the catalyst, and the hydrogen content obtained tends to decrease, while it is disadvantageous if the value is larger. However, it is disadvantageous in that it may lead to enlargement of steam generation equipment and steam recovery equipment.

The method of adding steam to the hydrocarbon compounds is not particularly limited, but it may be introduced into the reaction region at the same time as the starting hydrocarbon compound, or it may be introduced from different positions in the reaction region or divided into several times. You may introduce them part by part.

The oxygen supply amount and the steam supply amount can be appropriately determined in consideration of the composition of the reforming raw material, the composition of the reformed gas to be produced, the heat balance in the catalyst layer, the generation of coke, and the like. .

Further, the space velocity of the reforming raw material, the mixed gas containing steam and oxygen is GH on the basis of the total amount of the catalyst and converted into standard temperature / pressure (15 ° C., 1 atm {0.101 MPa}).
The SV is preferably set in the range of 500 to 1,000,000 h ^-1 , more preferably 1,000 to 800,000 h ^-1 , and most preferably 1,500 to 500,000 h ^-1 . At this time, the temperature in the reformer is preferably set to 2 by appropriately controlling the oxygen / carbon ratio and the space velocity.
00-1000 ° C, more preferably 300-900 ° C,
More preferably, the temperature is controlled to 500 to 800 ° C. Here, the catalyst amount does not include the filler in the low activity region, and oxygen is calculated including the amount added from the middle of the catalyst layer.

As the catalyst used in the catalyst layer, any catalyst that can be used for autothermal reforming, that is, one that has an oxidizing activity and a steam reforming activity can be used. For example, JP 2000-84410 A, JP 2001-80907 A, “2000 Annu”.
al Progress Reports (Official
e of Transportation Techn
It is known that nickel and precious metals such as platinum, rhodium and ruthenium have these activities, as described in U.S. Pat. No. 5,929,286. As the catalyst shape, a conventionally known shape can be appropriately adopted and may be a pellet shape or a honeycomb shape.

The autothermal reforming reformer and the autothermal reforming method of the present invention will be described below with reference to the drawings.

FIG. 1 shows an example of the autothermal reforming reformer of the present invention.

The reformer 10 is generally tubular or tubular in shape, and is filled with an ATR catalyst, that is, a catalyst having both steam reforming activity and oxidation activity. In this example, the low activity region 5 is provided in the middle of the catalyst layer by dividing the catalyst layer into a front catalyst layer 1a and a rear catalyst layer 1b. The low activity region is a region having no oxidation activity or a lower oxidation activity than the catalyst layers (1a, 1b). The reforming raw material, water vapor, and a gas containing a part of oxygen gas are supplied from the gas supply port 2, the additional oxygen gas is supplied to the low activity region from the low activity region oxygen introduction path 3, and the reformed gas outlet is provided. The reformed gas is discharged from 4.

When the low active region is provided in this way, the oxygen introduced from the low active region oxygen introduction path 3 does not cause an oxidation reaction in the low active region, or only a slight oxidation reaction occurs. In the low activity region, it diffuses into the gas that has passed through the upstream catalyst layer 1a on the upstream side and is sufficiently mixed and diluted. Next, when reaching the latter catalyst layer 1b, the oxygen gas has already been diluted, so that no heat spot occurs in the latter catalyst layer 1b.

In the low activity region, if the activity of the oxidation reaction is lower than that of the other catalyst layers (1a, 1b), such an effect can be achieved, but the diffusion is effectively promoted to prevent the generation of heat spots. In addition, the oxidation activity of the other catalyst layers (1a, 1b) is 70% or less, preferably 50% or less, more preferably 30% or less. Of course, the oxidation activity may be 0.

This low activity region may or may not have steam reforming activity. That is, in the low activity region, only the activity of the oxidation reaction needs to be smaller than that of the other catalyst layers.

The low activity region is not particularly limited as long as the additional oxygen gas is sufficiently mixed with the gas from the upstream in the region, but it is preferable to fill it with a suitable filler, for example. This filler is (1) a catalyst having a steam reforming activity and having an oxidizing activity smaller than that of other catalyst regions, (2) a catalyst having a steam reforming activity and having no oxidizing activity, and (3) a steam reforming activity. It is preferable to be selected from any of the mere fillers which have neither both of oxidative activity and oxidative activity.

The shape of the filler is preferably a shape that promotes diffusion of the added oxygen-containing gas, and examples thereof include a ball shape, a pellet shape, a foam shape and a ring shape. Moreover, you may mix and use them. The size is adjusted so that mixing is optimally performed in consideration of the tube diameter of the reactor, the gas flow rate, and the like.

Higher heat capacity of the filler is preferred, and ceramic balls, ceramic pellets, ceramic foams and ceramic rings formed of suitable ceramics are preferred. These ceramic fillers may have neither steam reforming activity nor oxidative activity as described above, or the ceramic filler may have steam activity and no or little oxidative activity. Alternatively, the carrier may have a surface on which a catalyst component having water vapor activity and no or little oxidation activity is carried.

The ceramic material is not limited, but may be one kind selected from aluminum oxide, silicon oxide, titanium oxide, zirconium oxide, magnesium oxide, or a combination of two or more kinds. it can.

In FIG. 1, the low activity region is provided only at one location in the catalyst layer, but as shown in FIG. 2, the low activity regions 5a and 5b are provided at each location, and the low activity region oxygen introduction path 3 is provided at each location.
You may make it supply oxygen from a and 3b. The number of low active regions may be 3 or more. These can be appropriately determined in consideration of conditions such as the feed rate of raw materials, the length of the reactor, and the balance between heat generation and heat absorption, but in general, 1
Providing a low activity region at a location is preferable because the balance between heat generation and heat absorption can be controlled to a considerable extent and the apparatus can be simplified.

In order to improve the uniformity of heat generation in the plane of the cross section of the reactor, the low activity region, especially when composed of a filler, should be packed in layers as shown in FIG. Is preferred.

The thickness ratio (volume ratio of filling amount) between the low activity region and the other catalyst layers is preferably in the range of 1: 3 to 1:50, particularly in the range of 1: 5 to 1:20. Is preferred. Within such a range, the position of the location where the low-activity region is provided and the number thereof can be determined so that the temperature distribution becomes optimum.

As shown in FIG. 1, a low active region is provided only at one place.
The thickness of the low active region (L _i) And other catalysts
Thickness with layer (L_C1+ L_C2) Ratio is from 1: 3 to 1:50
And typically 1: 9. In addition, (low active area
(The thickness of the catalyst layer in the previous stage): (Catalyst in the stage after the low activity region)
Layer thickness) ratio (L_C1: L_C2) Is from 0.5: 8.5
It is preferable to set it appropriately in the range of 8: 1, especially 2:
A range of 7 to 6: 3 is preferred.

The ratio of (amount of oxygen supplied from the inlet) :( amount of oxygen supplied from the low active region) is 3: 7 to 9: 1.
Is preferable, and a range of 5: 5 to 7: 3 is particularly preferable.

There is no particular limitation on the method of dividing and supplying the gas containing oxygen, and it is possible to control and supply by a valve or the like so that the supply amount of oxygen falls within a desired range. Or, more simply, as shown in FIG.
One oxygen-containing gas supply pipe 6 may be divided into an inlet-side oxygen introduction passage 7 and a low active region oxygen introduction passage 8, and the supply amount may be determined by the ratio of the opening cross-sectional areas of the respective outlets (for example, nozzles). Good. That is, (the opening cross-sectional area of the outlet of the inlet side oxygen introducing passage): (the opening cross-sectional area of the outlet of the low active region oxygen introducing passage) is in the range of 3: 7 to 9: 1, preferably 5: 5.
To 7: 3. The oxygen-containing gas supplied is
If the pressure is high enough to introduce gas to the inlet side or low activity area, and the pressure loss difference inside the pipe and the pressure difference at the outlet of the introduction path are negligible, a supply amount approximately proportional to the outlet cross-sectional area can be obtained. To be In this way, the method of determining the divided supply amount of oxygen by the cross section of the opening of the outlet does not require a complicated control device and thus has the advantage of simplifying the device configuration.

The outlet of the inlet-side oxygen introducing passage may be mixed with other gas before opening into the gas supply port 2 and entering the reformer as shown in FIG. If there is a dead space where the catalyst is not filled in the upper part of the catalyst layer, it does not matter whether it is opened in that part and mixed with other gas in the dead space.

The low active region oxygen introduction path is shown in FIG.
As shown in FIGS. 2 and 3, even if the side surface of the reactor is open to the low activity region, the low activity region oxygen introduction path 11 is extended to the inside of the low activity region as shown in FIG. It may be supplied. Further, by providing a plurality of oxygen introducing passages for one low activity region, oxygen can be further sufficiently mixed.

The method of changing the opening cross-sectional area described here is also effective when the oxygen gas is divided and supplied to the conventional apparatus having no low active region, and the inlet side oxygen introduction path and the catalyst are used. The supply ratio can be effectively changed by changing the opening cross-sectional area of the intermediate region oxygen introduction passage for supplying oxygen to the middle of the layer.

When the reforming reaction is carried out using the apparatus as described above, in addition to suppressing the generation of heat spots, the outlet temperature of the catalyst layer can be easily raised to 600 ° C. or higher.
A reformed gas having a high hydrogen content can be obtained by suppressing the slip of the raw material gas.

Since the reformed gas produced by using the above apparatus contains hydrogen and carbon monoxide, it is suitable for applications requiring a lower carbon monoxide concentration such as when used for fuel cells. Is a known shift process reactor or CO
Carbon monoxide can be reduced and used through a selective oxidation device.

[0057]

Example 1 A spherical Rh alumina catalyst 90 m having an average diameter of 1 mm was used for a reactor having an inner diameter of 20 mm (diameter).
1 was divided into 1st stage: 2nd stage = 50: 40 ml, and 10 ml of an α-alumina ball filler having an average diameter of 1 mm was laminated and filled between the catalyst layers of the 1st stage and 2nd stage. Cross-sectional area of catalyst layer 3.
14 cm ² , and the total height of the catalyst and the packed bed was 32 cm.

The reaction conditions are as follows: Desulfurized kerosene having a sulfur content of 1 mass ppm or less is used as a raw material, steam is steam / carbon ratio = 2, air is oxygen / carbon ratio = 0.5, and kerosene, steam and air are mixed. The gas was preheated to 450 ° C. and supplied to the catalyst layer. The air was divided into the front part of the catalyst layer and the α-alumina ball filler at a ratio of 6: 4.

The space velocity of kerosene, water vapor and air mixed gas is converted to standard temperature and pressure based on the total amount of gas supply and the total amount of catalyst (the amount of α-alumina ball filler is not included). Therefore, GHSV = 5,800 h ⁻¹ .

As a result of carrying out the reaction under such conditions, the maximum temperature in the catalyst layer is 710 ° C., and the catalyst layer outlet temperature is 630 ° C.
Met. The produced reformed gas had the following composition. H ₂ ; 40.0 vol% (dry) CO; 8.3 vol% CO ₂ ; 14.0 vol% CH ₄ ; 0.9 vol% undecomposed kerosene; 1 volppm or less

<Comparative Example 1> The same as that used in Example 1.
A reactor with an inner diameter of 20 mm (diameter), a sphere with an average diameter of 1 mm
90 ml of Rh alumina catalyst was charged. Cross section of catalyst layer
Product is 3.14 cm ²The height of the catalyst layer is 29 cm.
It was

The reaction conditions are as follows: Desulfurized kerosene with a sulfur content of 1 mass ppm or less is used as a raw material, steam is steam / carbon ratio = 2, air is oxygen / carbon ratio = 0.5, and kerosene, steam and air are mixed. The gas was preheated to 450 ° C. and supplied to the catalyst layer.

The space velocity of kerosene, water vapor, and air mixed gas is GHSV in terms of the total amount of catalyst, standard temperature / pressure conversion.
= 5,800 h ^-1 .

As a result of carrying out the reaction under such conditions, the maximum temperature in the catalyst layer was 910 ° C. and the catalyst layer outlet temperature was 470 ° C.
Met. The reformed gas composition produced had the following composition. H ₂ ; 37.5 vol% (dry) CO; 6.1 vol% CO ₂ ; 14.8 vol% CH ₄ ; 3.4 vol% undegraded kerosene content; 2500 volppm

[0065]

EFFECTS OF THE INVENTION According to the present invention, by suppressing the generation of heat spots, in addition to making the temperature distribution in the reactor length direction (the direction of the flow of the raw material gas) uniform, the lateral direction of the reactor (of the raw material gas By reforming the temperature distribution (in the plane orthogonal to the flow) to a uniform level, the deterioration of the catalyst can be reduced, and the reformed gas with a high hydrogen content can be obtained by suppressing the slip of the raw material gas. It is possible to provide an apparatus and a reforming method with high efficiency.

[Brief description of drawings]

FIG. 1 is a diagram showing an example of an autothermal reforming reformer of the present invention.

FIG. 2 is a diagram showing an example of an autothermal reforming reformer of the present invention.

FIG. 3 is a diagram showing an example of an autothermal reforming reformer of the present invention.

FIG. 4 is a diagram showing an example of an autothermal reforming reformer of the present invention.

FIG. 5 is a diagram showing a temperature distribution when a reforming raw material, steam, and oxygen are collectively introduced from the upstream of the catalyst layer.

FIG. 6 is a diagram showing an example of a conventional autothermal reforming reformer.

FIG. 7 is a diagram showing a temperature distribution when oxygen is divided and introduced from upstream and in the middle of the catalyst layer.

FIG. 8 is a diagram showing an example of a conventional autothermal reforming reformer.

FIG. 9 is a diagram schematically showing how a heat spot is generated when a conventional auto thermal reforming reformer is used.

FIG. 10 is a diagram schematically showing how a heat spot is generated when a conventional auto thermal reforming reformer is used.

[Explanation of symbols]

1a Pre-catalyst layer 1b Rear catalyst layer 2 gas supply ports 3, 3a, 3b Low active area oxygen introduction path 4 Reformed gas outlet 5, 5a, 5b Low active region 6 Oxygen-containing gas supply pipe 7 Entrance side oxygen introduction path 8 Low active area oxygen introduction path 10 reformer 11 Low active area oxygen introduction path

Claims (11)

[Claims] 1. An auto-thermal reforming reformer which comprises a catalyst layer, and supplies a reforming raw material, a gas containing steam and oxygen from the inlet side of the catalyst layer to produce a reformed gas. A low-activity region provided on the way, which has no oxidation activity or has a smaller oxidation activity than other regions, and an oxygen supply port for supplying at least a part of oxygen necessary for the reaction to this low-activity region are further provided. Auto thermal reforming reformer. 2. The low activity region has no oxidative activity,
The autothermal reforming reformer according to claim 1, which is a layer filled with a filler having an oxidizing activity lower than that of other regions. 3. The autothermal reforming reformer according to claim 2, wherein the filler is selected from the group consisting of ceramic balls, ceramic pellets, ceramic foams and ceramic rings. 4. The autothermal reforming reformer according to claim 1, wherein the low activity region is provided only at one location in the catalyst layer. 5. (Thickness of low activity region): (Catalyst layer thickness)
The ratio is in the range of 1: 3 to 1:50.
5. The auto thermal reforming reformer according to any one of 1. 6. The low activity region is provided only at one location in the catalyst layer, and (thickness of catalyst layer before the low activity region): (thickness of catalyst layer after the low activity region) 6. The autothermal reforming reformer according to claim 5, wherein the ratio is 0.5: 8.5 to 8: 1. 7. The autothermal according to claim 1, wherein a ratio of (amount of oxygen supplied from inlet) :( amount of oxygen supplied from low active region) satisfies 3: 7 to 9: 1. Reforming reformer. 8. An inlet-side oxygen introducing passage for supplying oxygen to the inlet side and a low-active area oxygen introducing passage for supplying oxygen to at least one low-active area, wherein The opening cross-sectional area of the outlet of the passage): (Opening cross-sectional area of the outlet of the low active region oxygen introduction passage) is in the range of 3: 7 to 9: 1. Forming reformer. 9. An auto-thermal reforming reformer comprising a catalyst layer, wherein a reforming gas is supplied from the inlet side of the catalyst layer to produce a reformed gas, and oxygen is introduced at the inlet side. An inlet-side oxygen introduction passage for supplying oxygen and at least 1 for supplying oxygen in the middle of the catalyst layer.
And one of the intermediate region oxygen introduction passages, (opening cross-sectional area of the outlet of the inlet side oxygen introduction passage): (opening cross-sectional area of the outlet of the intermediate region oxygen introduction passage) is 3: 7 to 9:
Auto thermal reforming reformer which is the range of 1. 10. A gas containing the reforming raw material and steam from the inlet side of the catalyst layer, and a part of the required oxygen amount, using the autothermal reforming reformer according to claim 1. Is supplied, and a reformed gas is produced by supplying a gas containing a required amount of residual oxygen from the middle of the catalyst layer. 11. A gas containing a reforming raw material and steam from the inlet side of a catalyst layer, and a part of a necessary oxygen amount, using the autothermal reforming reformer according to claim 1. And a gas containing a required amount of remaining oxygen from the middle of the catalyst layer, and the reformed gas is produced at a catalyst layer temperature of 600 ° C. or higher at the reformer outlet.