JP2011144088A - Two-stage hydrogen separation type reformer - Google Patents

Abstract

A hydrogen separation type reformer that can obtain a higher hydrogen recovery rate than a conventional reformer by using a Pd alloy hydrogen separation membrane and a 5A group metal alloy hydrogen separation membrane together.
SOLUTION: A hydrogen separation membrane is disposed on the outer peripheral surface of a rod-like or cylindrical porous support or a porous plate supporting the hydrogen separation membrane, and reformed on the outer periphery of the hydrogen separation membrane. A hydrogen separation system in which a plurality of hydrogen separation type reformers each having a catalyst layer are arranged in series, wherein the hydrogen separation membrane uses a Pd-based alloy hydrogen separation membrane on the upstream side of the gas to be treated A two-stage hydrogen separation reformer characterized in that a 5A group metal alloy hydrogen separation membrane is used on the downstream side of the gas to be treated.
[Selection] Figure 5

Description

  The present invention relates to a two-stage hydrogen separation reformer, and more specifically, a two-stage hydrogen separation reformer using a Pd alloy hydrogen separation membrane and a periodic table 5A group metal alloy hydrogen separation membrane. It relates to the genitalia.

  A Pd alloy hydrogen separation membrane is generally used as a hydrogen separation membrane of a conventional hydrogen separation reformer. In a hydrogen separation reformer, if a large number of hydrogen separation membranes are mounted on the input raw material gas, that is, the hydrogen-containing treated gas (treated gas containing hydrogen obtained by steam reforming of hydrocarbons, etc.), the hydrogen separation type reformer is separated. Although the amount of hydrogen to be produced can be increased and hydrogen can be produced efficiently, the Pd-based alloy hydrogen separation membrane is expensive and the apparatus becomes large.

To selectively permeate and purify hydrogen through a hydrogen separation membrane made of a Pd-based alloy and perform efficient hydrogen production, for example, primary pressure (reaction side) = 0.8 MPaG, secondary pressure (permeation side) = -0.06 to 0 MPaG, 500 to 550 ° C., S / C = 2.5 to 3.5, raw material input amount is ^{2 to} 6 cc / min / cm ² , preferably about 3 to 4 cc / min / cm ² It is suitable to drive at.

  In a hydrogen separation reformer using only a Pd-based alloy hydrogen separation membrane, even if the area of the hydrogen separation membrane is increased or the mounting amount of the hydrogen separation membrane module is increased under such optimized operating conditions. Thus, the amount of hydrogen production that is equivalent to the increase in the hydrogen separation membrane cannot be obtained.

For example, the apparent hydrogen permeation coefficient during hydrocarbon reforming is 0.7 × 10 ⁻⁸ mol · m ⁻¹ · s ⁻¹ · Pa ^−1/2 , length 450 mm, width 120 mm, thickness 20 μm A Pd-based alloy hydrogen separation membrane of 95 NL / h (approximately 3 cc / min / cm ² ) of 13 A city gas and S / C (water vapor / carbon ratio) = 3 of water vapor on the primary side (reaction side) Considering the case where hydrogen was produced at 550 ° C. with a secondary pressure (permeation side) of −0.06 MPaG and the membrane area was increased by 33.3% by 0.8 MPaG. Hydrogen production increases only 20.7% from 294 NL / h to 355 NL / h.

  By the way, the periodic table of elements such as Nb, V, Ta, etc., Group 5A metals or alloys containing Group 5A metals have a high hydrogen permeability coefficient Φ compared to Pd-based alloys such as Pd—Ag alloys. Since embrittlement occurs, it is difficult to use as a hydrogen separation membrane. Therefore, in order to suppress hydrogen embrittlement, methods for suppressing hydrogen embrittlement by adding additional elements have been proposed (Patent Documents 1 and 2). However, it is difficult to achieve both hydrogen embrittlement resistance and industrially important high hydrogen permeation rate by simply obtaining high solubility and hydrogen permeation coefficient by simply controlling what percentage of additive material is added. In addition to the addition amount, it is necessary to select an appropriate use temperature and use pressure (primary side and secondary side).

  The present inventors have first developed a method for obtaining an optimum condition for realizing a high hydrogen concentration difference while suppressing the amount of hydrogen solid solution by adding other components by using a PCT curve (= pressure composition temperature curve). (Patent Documents 3 and 4). According to this method, it was shown that pure Nb and Nb-W alloys can be used at low hydrogen partial pressure and low pressure difference by clarifying the conditions that do not cause brittle fracture. However, the maximum working pressure is below atmospheric pressure of 0.05 MPa (absolute pressure) and cannot be used at a high hydrogen partial pressure.

JP 2001-170460 A JP 2006-000722 A Japanese Patent Application No. 2008-072607 (filed on Mar. 19, 2008) Japanese Patent Application No. 2008-072609 (filed on Mar. 19, 2008)

  The present inventors have newly found a 5A group metal alloy hydrogen separation membrane that can be used even at a hydrogen partial pressure of atmospheric pressure or higher. That is, for example, at 500 ° C., a VW alloy hydrogen separation membrane can be used up to 0.3 MPa (absolute pressure), and a Ta—W alloy hydrogen separation membrane can be used up to 0.15 MPa (absolute pressure). It can be used. Then, it was clarified that the apparent hydrogen permeation coefficient at 500 ° C. is 5 times as large as that of the Pd—Ag alloy (FIGS. 1 to 4).

  In the present invention, for example, a VW alloy hydrogen separation membrane that can be used up to 0.3 MPa [= 3 atm (absolute pressure)] at 500 ° C., 0.15 MPa [= 1.5 atm (absolute pressure), for example. )]] By using Ta-W alloy hydrogen separation membranes that can be used up to and using them together with Pd alloy hydrogen separation membranes, that is, using both Pd alloy hydrogen separation membranes and Group 5A metal alloy hydrogen separation membranes Thus, an object of the present invention is to provide a two-stage hydrogen separation reformer that can obtain a higher hydrogen recovery rate than a conventional reformer.

  In the present invention (1), a hydrogen separation membrane is arranged on the outer peripheral surface of a cylindrical porous support or a porous plate supporting the hydrogen separation membrane, and reformed on the outer periphery of the hydrogen separation membrane. A hydrogen separation reformer comprising a catalyst layer, wherein the hydrogen separation membrane uses a Pd-based alloy hydrogen separation membrane on the upstream side of the gas to be treated, and a group 5A on the downstream side of the gas to be treated. A two-stage hydrogen separation reformer characterized by using a metal alloy hydrogen separation membrane.

  The present invention (2) is a hydrogen separation type in which a hydrogen separation membrane is disposed on the outer peripheral surface of a cylindrical reforming catalyst / porous support that simultaneously serves as a reforming catalyst and supports a hydrogen separation membrane. In the reformer, the hydrogen separation membrane uses a Pd-based alloy hydrogen separation membrane on the upstream side of the gas to be treated, and uses a 5A group metal alloy hydrogen separation membrane on the downstream side of the gas to be treated. Is a two-stage hydrogen separation reformer characterized by

  In the present invention (3), a hydrogen separation membrane is disposed on the outer peripheral surface of a bowl-shaped porous support that plays a role of supporting the hydrogen separation membrane, and a reforming catalyst layer is disposed on the outer periphery of the hydrogen separation membrane. In the hydrogen separation type reformer, the hydrogen separation membrane uses a Pd alloy hydrogen separation membrane on the upstream side of the gas to be treated, and uses a 5A group metal alloy hydrogen separation membrane on the downstream side of the gas to be treated. A two-stage hydrogen separation reformer characterized by comprising:

  The present invention (4) is a hydrogen separation reforming in which a hydrogen separation membrane is disposed on the outer peripheral surface of a bowl-shaped reforming catalyst / support that simultaneously serves as a reforming catalyst and supports a hydrogen separation membrane. The hydrogen separation membrane is characterized in that a Pd-based alloy hydrogen separation membrane is used on the upstream side of the gas to be processed, and a group 5A metal alloy hydrogen separation membrane is used on the downstream side of the gas to be processed. Is a two-stage hydrogen separation reformer.

  In the two-stage hydrogen separation reformer of the present invention (1) to (4), the 5A group metal alloy hydrogen separation membrane used on the downstream side of the gas to be treated includes a VW alloy hydrogen separation membrane, Ta— A W-based alloy hydrogen separation membrane can be used.

According to the present invention, the following effects (1) to (4) can be obtained.
(1) A hydrogen separation type reformer that can obtain a higher hydrogen recovery rate than a conventional reformer from a raw fuel such as natural gas can be realized.
(2) By reducing the amount of noble metal used such as Pd, the cost of the hydrogen separation membrane can be reduced. If the same amount of hydrogen production as before is required, a group 5A metal alloy hydrogen separation membrane can be provided in the subsequent stage to reduce the amount of the Pd-based alloy hydrogen separation membrane in the previous stage.
(3) With the two-stage hydrogen separation membrane, a hydrogen production amount equivalent to that at 550 ° C. can be obtained only at the Pd-based alloy hydrogen separation membrane even at 500 ° C.
(4) Since hydrogen is extracted at a high recovery rate, the CO ₂ concentration in the reformer off-gas increases, and efficient CO ₂ separation and recovery from the off-gas by compression liquefaction becomes possible.

FIG. 1 is a graph plotting the relationship between the hydrogen pressure P of the atmosphere and the amount of dissolved hydrogen C at temperatures of 400 ° C., 450 ° C., and 500 ° C. for the VW type alloy film. FIG. 2 is a diagram showing test conditions and results of a hydrogen permeation rate test for Pd-26Ag alloy, Nb-5W alloy, and V-5W alloy. FIG. 3 is a graph plotting the relationship between the hydrogen pressure P of the atmosphere and the amount C of solute hydrogen at temperatures of 400 ° C., 450 ° C., and 500 ° C. for the Ta—W alloy film. FIG. 4 is a diagram showing test conditions and results of a hydrogen permeation rate test for a Pd-26Ag alloy and a Ta-5W alloy. FIG. 5 is a diagram for explaining a configuration example 1 of the present invention. FIG. 6 is a diagram for explaining a configuration example 1 of the present invention. FIG. 7 is a diagram for explaining a configuration example 2 of the present invention. FIG. 8 is a diagram for explaining a configuration example 3 of the present invention. FIG. 9 is a diagram for explaining a configuration example 4 of the present invention.

  In the present invention (1), a hydrogen separation membrane is arranged on the outer peripheral surface of a cylindrical porous support or a porous plate supporting the hydrogen separation membrane, and reformed on the outer periphery of the hydrogen separation membrane. It is a hydrogen separation type reformer formed by arranging a catalyst layer. The hydrogen separation membrane is characterized in that a Pd-based alloy hydrogen separation membrane is used on the upstream side of the gas to be processed, and a 5A group metal alloy hydrogen separation membrane is used on the downstream side of the gas to be processed.

  The present invention (2) is a hydrogen separation type in which a hydrogen separation membrane is disposed on the outer peripheral surface of a cylindrical reforming catalyst / porous support that simultaneously serves as a reforming catalyst and supports a hydrogen separation membrane. It is a reformer. The hydrogen separation membrane is characterized in that a Pd-based alloy hydrogen separation membrane is used on the upstream side of the gas to be processed, and a 5A group metal alloy hydrogen separation membrane is used on the downstream side of the gas to be processed.

  In the present invention (3), a hydrogen separation membrane is disposed on the outer peripheral surface of a bowl-shaped porous support that plays a role of supporting the hydrogen separation membrane, and a reforming catalyst layer is disposed on the outer periphery of the hydrogen separation membrane. This is a hydrogen separation type reformer. The hydrogen separation membrane is characterized in that a Pd-based alloy hydrogen separation membrane is used on the upstream side of the gas to be processed, and a 5A group metal alloy hydrogen separation membrane is used on the downstream side of the gas to be processed.

  The present invention (4) is a hydrogen separation reforming in which a hydrogen separation membrane is disposed on the outer peripheral surface of a bowl-shaped reforming catalyst / support that simultaneously serves as a reforming catalyst and supports a hydrogen separation membrane. It is a vessel. The hydrogen separation membrane is characterized in that a Pd-based alloy hydrogen separation membrane is used on the upstream side of the gas to be processed, and a 5A group metal alloy hydrogen separation membrane is used on the downstream side of the gas to be processed.

  In the two-stage hydrogen separation reformer of the present invention (1) to (4), the 5A group metal alloy hydrogen separation membrane used on the downstream side of the gas to be treated includes a VW alloy hydrogen separation membrane, Ta— A W-based alloy hydrogen separation membrane can be used.

For example, in hydrogen separation using a Pd-based alloy hydrogen separation membrane, the Sievert's law (C = KP ^1/2, hereinafter abbreviated as “Siebert's law”) is used, so a high hydrogen permeation amount J (J = D · ΔC / d, D is a diffusion coefficient, ΔC is a solid solution hydrogen amount difference, and d is a film thickness), but a certain hydrogen partial pressure difference (ΔP) is required, but Nb does not follow the Siebelz rule I found that there was a region. For this reason, if a hydrogen pressure difference or a hydrogen partial pressure difference occurs even at a low hydrogen concentration, a high solid solution hydrogen amount difference (ΔC) can be obtained, and a high hydrogen permeation amount (J) can be obtained.

  By measuring the PCT curve at the operating temperature, the usable hydrogen pressure of the alloy can be determined. For example, at 500 ° C., the hydrogen partial pressure is 0.3 MPa (= 3 atmospheres (absolute pressure)) or less for V-W alloys and 0.15 MPa (= 1.5 atmospheres (absolute pressure)) for Ta-W alloys. Can be used as a hydrogen separation membrane (FIGS. 1 and 3).

  Also, depending on the pressure condition from the evaluation of the J · d value, which is the product of the hydrogen permeation flux J and the film thickness d of the alloy, the VW alloy and the Ta—W alloy may be compared with the Pd—Ag alloy. It was found that a high hydrogen permeation rate was obtained (FIGS. 2 and 4).

As shown in FIG. 2, at 500 ° C., when hydrogen permeation condition, process side (primary side) / permeation side (secondary side) = 0.20 MPa / 0.01 MPa, the apparent hydrogen permeation capacity Φ is Pd-26Ag alloy Is 2.3 × 10 ⁻⁸ (mol ⁻¹ · m ⁻¹ · s ⁻¹ · Pa ^−1/2 ), whereas V-5W alloy film 1.2 × 10 ⁻⁷ (mol ⁻¹ · m ⁻¹ · s ⁻¹ · Pa ^−1/2 ) and about 5 times as long as a separation membrane having the same area and thickness, a hydrogen permeation amount of about 5 times can be obtained.

The gas composition in the terminal portion of the Pd-based alloy hydrogen separation membrane described above is CH ₄ = 7.0%, H ₂ O = 51.6%, CO ₂ = 26.9%, H ₂ = 12. 6%, and the hydrogen partial pressure at the outlet portion is 0.11 MPa (absolute pressure). Therefore, even if the pressure on the process gas side is 0.8 MPaG, the VW system is used in the subsequent stage of the Pd-based alloy hydrogen separation membrane. An alloy hydrogen separation membrane or a Ta-W alloy hydrogen separation membrane can be used.

  If a hydrogen separation membrane using a V-W alloy membrane or a Ta-W alloy membrane is installed at a position after the Pd alloy hydrogen separation membrane and at a temperature above the reformer, the Pd alloy It is possible to realize a hydrogen separation reformer that further separates hydrogen from the process-side off-gas of the hydrogen separation membrane to obtain a high hydrogen production amount.

After the above-mentioned Pd alloy hydrogen separation membrane, the length is 150 mm (33.3% of the Pd alloy hydrogen separation membrane), the width is 120 mm, and the thickness is 40 μm (because the workability is lower than that of the Pd alloy). 5A group metal alloy hydrogen separation membrane with a coefficient of 3.5 × 10 ⁻⁸ mol ⁻¹ · m ⁻¹ · s ⁻¹ · Pa ^−1/2 (about 5 times that of Pd—Ag alloy) When installed below, the raw material conversion rate increases from 80.4% in the case of only the Pd alloy hydrogen separation membrane to 91.1%, and the hydrogen production amount is 367 NL / h and only the Pd alloy hydrogen separation membrane is used. Increase by 24.8% against the hydrogen production amount of 294 NL / h. Thus, compared with the case where the area of the Pd-based alloy hydrogen separation membrane is increased, a low-cost and high-efficiency hydrogen separation reformer can be realized.

  When the Pd-based alloy hydrogen separation membrane is used at 550 ° C., if the hydrogen partial pressure at the terminal portion of the Pd-based alloy hydrogen separation membrane is 0.15 MPa (absolute pressure) or less, the V-W type alloy hydrogen separation membrane is used. And the Ta—W alloy hydrogen separation membrane can be used, the length of the Pd alloy hydrogen separation membrane is reduced from 450 cm to 300 cm [the hydrogen partial pressure at the terminal portion of the Pd alloy hydrogen separation membrane is 0. 14 MPa (absolute pressure)] and a 150 cm 5A group metal alloy hydrogen separation membrane may be installed in the subsequent stage.

  That is, a part of the Pd-based alloy hydrogen separation membrane can be replaced with a 5A group metal alloy hydrogen separation membrane. At this time, the raw material conversion is 82.8%, and the hydrogen production amount is increased by 10.3% from 294 NL / h to 325 NL / h compared to the case of only the Pd-based alloy hydrogen separation membrane. If the thickness of the Group 5A metal alloy hydrogen separation membrane can be reduced to 20 μm, the raw material conversion will be 93.9%, and the hydrogen production will increase by 29.8% to 382 NL / h.

It is possible to bring the entire reaction furnace to a substantially uniform temperature. When the operation is performed at 500 ° C., the hydrogen partial pressure is sufficiently reduced to 0.degree. If there is a Pd-based alloy hydrogen separation membrane only at the inlet of the reaction tube. It can be lowered to 15 MPa (absolute pressure) or less. 95 NL / h (approximately 3 cm ³ / min / cm ² ) of 13 A city gas, S / C (steam / carbon ratio) = 3 steam, and primary side (reformed side) at 0.8 MPaG were added. When hydrogen production is performed at 500 ° C. with a secondary side (permeation side) of −0.06 MPaG, when the length of the Pd alloy hydrogen separation membrane is 90 cm (20% of 450 cm), the end of the Pd alloy hydrogen separation membrane The hydrogen partial pressure in the portion is 0.13 MPa (absolute pressure), and a 5A metal alloy hydrogen separation membrane can be used in the subsequent stage.

  When the length of the group 5A metal alloy hydrogen separation membrane is 360 cm (80% of 450 cm), the amount of hydrogen produced is 306 NL / h, compared to 294 NL / h in the case of only 550 ° C. and Pd alloy hydrogen separation membrane. Increase by 4.0%. As a result, the amount of Pd-based alloy hydrogen permeation can be greatly reduced, not only reducing raw material costs, but also reducing the input energy for heating the reaction tube by lowering the operating temperature of the reactor, High efficiency can be achieved by keeping energy loss such as heat radiation low.

Further, since hydrogen is extracted from the reformed gas, that is, the hydrogen-containing gas, at a high recovery rate, the CO ₂ concentration in the off-gas of the reformer relatively increases. At the time of 100% output of the applicant's 40 Nm ³ / h membrane reformer (improved type) that currently achieves the world's highest efficiency = 40 Nm ³ / h The CO ₂ concentration in the reformer off-gas during hydrogen production is 72.2 %, But depending on the conditions, higher CO ₂ concentrations can be obtained. From the off-gas of the two-stage hydrogen separation reformer, CO ₂ can be separated and recovered with higher efficiency only by compression liquefaction.

<Configuration Example 1 of the Present Invention>
5-6 is a figure explaining the structural example 1 of this invention. FIG. 5A is a perspective view of the hydrogen separator 1 provided with two types of alloy membranes, and FIG. 5B is a cross-sectional view of the container 3 containing the hydrogen separator 1 provided with two types of alloy hydrogen separation membranes. It is. As shown as the reforming catalyst layer in FIGS. 5B and 6A, the reforming catalyst layer is disposed between the container 3 and the hydrogen separator 1 accommodated therein.

  As shown in FIG. 5 (a), the hydrogen separator 1 includes two types of alloy hydrogen separation membranes, a Pd alloy hydrogen separation membrane and a 5A group metal alloy hydrogen separation membrane, spaced apart from each other on the left and right sides of the alloy casing. Sequentially arranged. As for the arrangement of the two types of alloy hydrogen separation membranes, a Pd-based alloy hydrogen separation membrane is first arranged, and then a Group 5A metal alloy hydrogen separation membrane is arranged, as viewed in the flow direction of the process gas (raw fuel + water vapor). A reforming catalyst layer is disposed between the hydrogen separator 1 and the bowl-shaped vessel 3. Reference numeral 4 denotes a process gas introduction pipe, which is open at the lower end thereof.

  A process gas, which is a mixed gas of raw fuel and water vapor, is introduced through the introduction pipe 4. The process gas released to the lower end portion in the container 3 is reformed while raising the gap between the hydrogen separator 1 and the container 3 to generate hydrogen. The process gas containing the generated hydrogen is first purified through a Pd-based alloy hydrogen separation membrane in the hydrogen separator 1 while raising the gap between the hydrogen separator 1 and the vessel 3, and further, a group 5A metal It is purified by permeating the alloy hydrogen separation membrane. Purified hydrogen is taken out through the hydrogen outlet pipe 5.

  FIG. 6B shows the relationship between the process gas side hydrogen partial pressure and the distance from the lower end of the hydrogen separator 1 (separation membrane module). Since the group 5A metal alloy hydrogen separation membrane is effective in a region where the process gas side hydrogen partial pressure is small, as shown as “group 5A metal alloy hydrogen separation membrane” in FIG. The separation membrane module is disposed at the upper end of the separation membrane module, that is, at a location where the distance from the lower end is large.

  In FIG. 6B, the left side of the dotted line shown as “Upper limit of hydrogen partial pressure that can be used for group 5A metal alloy film” is a region where the process gas side hydrogen partial pressure is low, and “group 5A metal alloy film” is arranged in that region. (A region including a portion shown as “Group 5A metal alloy film” in FIG. 6A). This point is the same as in <Structural aspect example 2> to <Structural aspect example 4 of the present invention>.

<Configuration Example 2 of the Present Invention>
FIG. 7 is a diagram for explaining a configuration aspect example 2 of the present invention. FIG. 7A is a perspective view of the hydrogen separators 1 and 2 in which two types of alloy hydrogen separation membranes are respectively arranged in two casings, and FIG. 7B is a hydrogen in which two types of alloy hydrogen separation membranes are installed. It is sectional drawing of the bowl-shaped container 3 which accommodated the separator 1. FIG. As shown as a reforming catalyst layer in FIG. 7B, a reforming catalyst layer is disposed between the bowl-shaped container 3 and the hydrogen separator 1 accommodated therein. When the reforming catalyst layer is described with reference to FIG. 6A, the reforming catalyst layer is arranged in layers from the lower part to the upper part.

  As shown in FIG. 7A, the hydrogen separator 1 is configured by arranging Pd-based alloy hydrogen separation membranes on both the left and right sides of the lower casing made of an alloy, and the hydrogen separator 2 is formed on both the left and right sides of the upper casing made of an alloy. And 5A group metal alloy hydrogen separation membrane. In the hydrogen separator 1, Pd-based alloy hydrogen separation membranes are arranged on both the left and right sides of the alloy casing, and in the hydrogen separator 2, a group 5A metal alloy hydrogen separation membrane is arranged on both the left and right sides of the alloy casing. .

  The hydrogen separator 1 and the hydrogen separator 2 are arranged in the flow direction of the process gas (raw fuel + steam). First, the hydrogen separator 1 on which the Pd-based alloy hydrogen separation membrane is arranged is arranged, and then the group 5A A hydrogen separator 2 in which a metal alloy hydrogen separation membrane is disposed is disposed. The hydrogen separator 1 and the hydrogen separator 2 are connected by a connecting pipe K. A reforming catalyst layer is disposed between the hydrogen separator 1, the hydrogen separator 2, and the bowl-shaped container 3. Reference numeral 4 denotes a process gas introduction pipe, which is open at the lower end thereof.

  A process gas, which is a mixed gas of raw fuel and water vapor, is introduced through the introduction pipe 4. The process gas released to the lower end in the vessel 3 is reformed while raising the gap between the hydrogen separator 1, the hydrogen separator 2 and the bowl-like vessel 3 to generate hydrogen. The process gas containing the produced hydrogen is first purified through the Pd-based alloy hydrogen separation membrane of the hydrogen separator 1 while ascending the gap between the hydrogen separator 1, the hydrogen separator 2 and the bowl-shaped vessel 3. Further, it is purified by permeating through the hydrogen separation membrane of Group 5A metal alloy of the hydrogen separator 2. Purified hydrogen is taken out through the hydrogen outlet pipe 5.

<Configuration Example 3 of the Present Invention>
FIG. 8 is a diagram for explaining a configuration aspect example 3 of the present invention. FIG. 8A is a perspective view of the hydrogen separator 11 in which two types of alloy hydrogen separation membranes are installed on the peripheral surface of the cylindrical porous support, and FIG. 8B is a hydrogen in which two types of alloy hydrogen separation membranes are installed. It is sectional drawing of the separator 11 and the cylindrical container 13 which accommodated this. As shown as a reforming catalyst layer in FIG. 8B, the reforming catalyst layer is disposed between the cylindrical vessel 13 and the hydrogen separator 11 accommodated therein.

  As shown in FIG. 8 (a), the hydrogen separator 11 has two types of Pd-based alloy hydrogen separation membrane and 5A group metal alloy hydrogen separation membrane spaced from each other on the outer peripheral surface of a cylindrical porous support made of an alloy. The alloy hydrogen separation membrane is sequentially arranged. As for the arrangement of the two types of alloy hydrogen separation membranes, a Pd-based alloy hydrogen separation membrane is first arranged, and then a Group 5A metal alloy hydrogen separation membrane is arranged, as viewed in the flow direction of the process gas (raw fuel + water vapor). A reforming catalyst layer is disposed between the hydrogen separator 11 and the cylindrical vessel 13. Reference numeral 14 denotes a process gas introduction pipe which opens at the bottom of the cylindrical container 13.

  A process gas, which is a mixed gas of raw fuel and water vapor, is introduced through the introduction pipe 14. The process gas released to the lower end portion in the cylindrical container 13 is reformed while raising the gap between the hydrogen separator 11 and the cylindrical container 13 to generate hydrogen. The process gas containing the generated hydrogen is first purified through the Pd-based alloy hydrogen separation membrane in the hydrogen separator 1 while rising in the gap between the hydrogen separator 1 and the cylindrical vessel 3, and further 5A. It is refined by permeating the hydrogen separation membrane. Purified hydrogen is taken out through the hydrogen outlet pipe 5. The offgas after reforming the process gas and permeating and purifying the hydrogen in this way (process gas offgas which is the remaining gas after separating hydrogen) is discharged and taken out through the outlet pipe 16.

<Configuration Example 4 of the Present Invention>
FIG. 9 is a diagram illustrating a configuration aspect example 4 of the present invention. FIG. 9A is a perspective view of a hydrogen separator 11 which is cylindrical and has two kinds of alloy hydrogen separation membranes installed on the outer peripheral surface of a porous support having a reforming catalyst function, and FIG. It is sectional drawing of the hydrogen separator 11 which installed this alloy hydrogen separation membrane, and the cylindrical container 13 which accommodated this.

  As shown in FIG. 9 (a), the hydrogen separator 11 has a Pd-based alloy hydrogen separation membrane and a 5A group metal alloy hydrogen separation spaced from each other on the outer peripheral surface of a cylindrical porous support made of an alloy and having a reforming catalyst function. Two types of alloy hydrogen separation membranes with the membrane are sequentially arranged. As for the arrangement of the two types of alloy hydrogen separation membranes, a Pd-based alloy hydrogen separation membrane is first arranged, and then a Group 5A metal alloy hydrogen separation membrane is arranged, as viewed in the flow direction of the process gas (raw fuel + water vapor).

  A process gas (raw fuel + water vapor) introduction pipe 14 is disposed in a cylindrical inner space of the porous support having a cylindrical reforming catalyst function. A process gas, which is a mixed gas of raw fuel and water vapor, is introduced through the introduction pipe 14. Since the introduction pipe 14 is opened at the lower end, the process gas is turned back at the opening end, and while the gap between the introduction pipe 14 and the cylindrical porous support is raised, the reforming catalyst function of the porous support is achieved. To produce hydrogen.

  The process gas containing the produced hydrogen is first purified through the Pd-based alloy hydrogen separation membrane in the hydrogen separator 1 while raising the gap between the hydrogen separator 1 and the process gas introduction pipe 14. It is purified by permeating through a 5A group metal alloy hydrogen separation membrane. Purified hydrogen flows between the hydrogen separator 1 and the cylindrical container 13 and is taken out via the hydrogen outlet pipe 15.

1, 2, 11 Hydrogen separator 3 Casket-shaped vessel 13 Cylindrical vessel 4, 14 Process gas (raw fuel + water vapor) introduction pipe 5, 15 Hydrogen lead-out pipe 16 Process gas off-gas lead-out pipe

Claims (5)

A hydrogen separation membrane is arranged on the outer peripheral surface of a cylindrical porous support or a porous plate supporting the hydrogen separation membrane, and a reforming catalyst layer is arranged on the outer periphery of the hydrogen separation membrane. A hydrogen separation type reformer,
The hydrogen separation membrane is a two-stage type characterized in that a Pd-based alloy hydrogen separation membrane is used on the upstream side of the gas to be processed, and a 5A group metal alloy hydrogen separation membrane is used on the downstream side of the gas to be processed. Hydrogen separation type reformer. A hydrogen separation type reformer in which a hydrogen separation membrane is disposed on the outer peripheral surface of a cylindrical reforming catalyst / porous support that simultaneously serves as a reforming catalyst and supports a hydrogen separation membrane,
The hydrogen separation membrane is a two-stage type characterized in that a Pd-based alloy hydrogen separation membrane is used on the upstream side of the gas to be processed, and a 5A group metal alloy hydrogen separation membrane is used on the downstream side of the gas to be processed. Hydrogen separation type reformer. A hydrogen separation membrane is disposed on the outer peripheral surface of a cage-like porous support or a porous plate supporting the hydrogen separation membrane, and a reforming catalyst layer is disposed on the outer periphery of the hydrogen separation membrane. A hydrogen separation type reformer,
The hydrogen separation membrane is a two-stage type characterized in that a Pd-based alloy hydrogen separation membrane is used on the upstream side of the gas to be processed, and a 5A group metal alloy hydrogen separation membrane is used on the downstream side of the gas to be processed. Hydrogen separation type reformer. A hydrogen separation type reformer comprising a hydrogen separation membrane disposed on the outer peripheral surface of a bowl-shaped reforming catalyst / support that simultaneously serves as a reforming catalyst and supports a hydrogen separation membrane,
The hydrogen separation membrane is a two-stage type characterized in that a Pd-based alloy hydrogen separation membrane is used on the upstream side of the gas to be processed, and a 5A group metal alloy hydrogen separation membrane is used on the downstream side of the gas to be processed. Hydrogen separation type reformer. The two-stage hydrogen separation reformer according to any one of claims 1 to 4, wherein the 5A group metal alloy hydrogen separation membrane used downstream of the gas to be treated is a VW alloy hydrogen separation membrane, A two-stage hydrogen separation reformer characterized by being a Ta-W alloy hydrogen separation membrane.

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