JP3970992B2 - Hydrogen separator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a structure of a hydrogen separator using a hydrogen separation membrane that selectively permeates only hydrogen gas from a hydrogen mixed gas.
[0002]
[Prior art]
Hydrogen gas is used in large quantities as a basic raw material gas for petrochemicals, and high expectations are placed on it as a clean energy source. High-purity hydrogen gas is obtained by converting natural gas, naphtha or the like into a gas containing hydrogen using a catalyst, and further separating the hydrogen gas from the hydrogen-containing gas.
[0003]
Specifically, it can be separated by utilizing the property that palladium or a palladium alloy selectively transmits only hydrogen gas.
Usually, a hydrogen separator in which a thin film of palladium or a palladium alloy is deposited on the surface of a tubular porous substrate such as ceramics is used (Japanese Patent Laid-Open No. 62-273030).
[0004]
Further, in order to improve the processing capacity of such a hydrogen separator, the membrane area of the hydrogen separator per unit volume is improved, and an integrated structure (hereinafter referred to as a monolithic structure) in which a plurality of through holes are formed. A so-called monolithic hydrogen separator is disclosed in which a palladium thin film is deposited on the inner surface of a through-hole (Japanese Patent Laid-Open No. 8-40703).
[0005]
By the way, the hydrogen separation ability of palladium is exhibited only at a high temperature and a high pressure of 5 to 10 atmospheres and 300 to 500 ° C. Therefore, both ends of the hydrogen separator made of ceramics are sealed in a sealed container made of metal containing the hydrogen separator. If fixed, the hydrogen separator may be damaged due to the difference in thermal expansion coefficient between the two.
For this reason, only one end of the hydrogen separator is fixed to the sealed container and supported in a suspended form, and the end on the non-supporting side is set to an unfixed state, whereby the difference in thermal expansion between the hydrogen separator and the sealed container is achieved. Has been disclosed (Japanese Patent Laid-Open No. 6-191802).
[0006]
[Problems to be solved by the invention]
However, when the above-described suspended support is applied to a hydrogen separator using a monolith type hydrogen separator, the following problems occur.
[0007]
In the conventional tube-type hydrogen separator, a palladium membrane is formed on the outer surface of the tubular porous substrate. When the gas to be treated is introduced into the sealed container 34 from the inlet 36 as shown in FIG. The hydrogen gas contained in the processing gas permeates to the inner wall side of the tubular hydrogen separator 35 and is recovered from the outlet port 38 via the upper chamber 42 and the processing residual gas is discharged from the recovery port 37. .
[0008]
On the other hand, in the case of the monolith type hydrogen separator 55, in order to improve the membrane area per unit volume of the hydrogen separator 55, it is essential to form a palladium membrane on the inner surface of the through hole of the porous substrate. 3, when the gas to be treated is introduced into the sealed container 54 from the introduction port 56, it flows into the through hole from the support side end of the hydrogen separator 55 via the upper chamber 62, and the hydrogen gas is palladium It passes through the membrane and is discharged to the outer periphery of the hydrogen separator 55.
[0009]
Therefore, a partition should be provided at the end of the non-supporting side of the hydrogen separator 55, or the end of the non-supporting side of the hydrogen separator 55 should be connected to a pipe communicating with the outside of the container 54 by a flange. In this case, the separated hydrogen gas and the processing residual gas are mixed.
However, in such a structure, both ends of the hydrogen separator are fixed to the sealed container, and it is not possible to avoid problems associated with the difference in thermal expansion between the hydrogen separator and the sealed container.
That is, an object of the present invention is to avoid problems associated with a difference in thermal expansion between a hydrogen separator and a sealed container, such as damage to the hydrogen separator, in a hydrogen separator using a monolith type hydrogen separator.
[0010]
[Means for Solving the Problems]
The present invention provides a plurality of hydrogen separators formed by forming a large number of through holes in parallel in the longitudinal direction of a porous substrate, and depositing a hydrogen separation membrane on the inner surface of the through holes, and a gas to be processed. In a hydrogen separator comprising an inlet, a recovery port for recovering separated separation gas, and an outlet for extracting separated hydrogen gas, one end of the hydrogen separator is connected to the sealed container. It is fixed to a partition plate provided so as to be separated into two upper and lower chambers, and is supported in a suspended form. A large number of through holes of each hydrogen separator are divided into two through holes of a treated gas introduction path and a separation residual gas recovery path. The untreated side ends of each of the hydrogen separators are sealed with a gap portion by a crowning member and sealed to be treated through the through holes in the support side ends of the hydrogen separators. Gas is passed through the hydrogen separator to reciprocate, and the support side end A hydrogen separation apparatus characterized by allowing the difference in thermal expansion between the compressor housing hydrogen separator by recovering from the through-hole.
[0011]
In the hydrogen-separation device, the hydrogen separation membrane, has preferably be made of an alloy containing palladium or palladium.
[0012]
In the hydrogen separator of the present invention, in the upper chamber of the sealed container, the introduction port, the gas introduction path to be processed, and the recovery port and the separation residual gas recovery path are communicated with each other by a tubular member, and the separated hydrogen gas is It is preferable to collect from the outlet provided in the.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Since the present invention relates to the structure of a hydrogen separator, first, the configuration of a general hydrogen separator will be outlined with reference to the illustrated example.
For example, as shown in FIG. 4, the hydrogen separator is configured by accommodating a plurality of hydrogen separators 75 in a sealed container 74 including a container body 72 and a lid 73.
[0014]
The container main body 72 is a bottomed cylindrical body having an outward flange 79 on the outer peripheral edge of the upper end opening, and is formed with an introduction port 76 and a recovery port 77 communicating with the outside of the container 74, and the lid 73 is located outside the open end. A dome shape having an outward flange 80 at the peripheral edge, and a lead-out port 78 communicating with the outside of the container 74 is formed at the center of the top of the lid 73.
The container main body 72 and the lid 73 constitute a sealed container 74 in which the partition plate 81 is hermetically sandwiched between the outward flanges 79 and 80 and the inside of the container 74 is partitioned into an upper chamber 82 and a lower chamber 83.
[0015]
The hydrogen separator 75 is formed by depositing a thin film of palladium or a palladium alloy on the outer surface of a tubular porous substrate, and is hermetically fixed to the partition plate 81 with the upper opening end opened to the upper chamber 82. Then, it is supported in a suspended manner in the lower chamber 83.
Note that the lower opening end is hermetically sealed by the crown member.
[0016]
In the hydrogen separator 71 configured as described above, the gas to be processed is supplied from the inlet 76 into the lower chamber 83 of the sealed container 74, and only the hydrogen gas in the gas to be processed selects the separation membrane on the outer surface of the hydrogen separator 75. Permeated and flows into the hydrogen separator 75 and is collected from the outlet 78 through the upper chamber 82 from the upper opening end.
On the other hand, gas components other than hydrogen in the gas to be treated are discharged from the recovery port 77 without passing through the separation membrane.
[0017]
The hydrogen separator according to the present invention uses a monolith type hydrogen separator in the hydrogen separator as described above, and hydrogen-separates the gas to be treated introduced from the through hole at the support side end of the hydrogen separator. It is inserted so as to reciprocate inside the body, and is recovered from the through hole at the support side end.
In this way, even in the case of a monolith type hydrogen separator, there is no need to collect the gas to be treated from the through-hole at the non-support side end, so the non-support side end is constrained by a tubular member or partition wall. Therefore, it is possible to avoid problems associated with the difference in thermal expansion between the hydrogen separator and the sealed container.
[0018]
As an example of a structure in which the gas to be processed can be inserted so as to reciprocate in the hydrogen separator, a large number of through holes of the hydrogen separator are provided with a gas to be processed introduction path (hereinafter referred to as an introduction path) and a separation residual gas recovery path ( Hereinafter, the structure is divided into two groups of recovery paths), and the non-support side end portions of the respective hydrogen separators are sealed with a gap portion by a crowning member.
[0019]
The above structure will be specifically described below.
First, in a monolith having a large number of through-holes, about half of the through-hole groups are assigned to the introduction path, and the remaining through-hole groups are assigned to the recovery path.
Next, when the gas to be treated is introduced from the opening on the support side end face of the hydrogen separator in the through hole group assigned to the introduction path, the gas to be treated passes through the introduction path to the non-support side end of the hydrogen separator. Reach.
[0020]
Here, since the non-support side end portion is sealed with the crown member in a state having a gap portion, the gas to be processed passes through the gap portion and flows into the recovery path having a lower pressure, and again It passes through the hydrogen separator and is recovered from the opening on the support side end face of the through hole group assigned to the recovery path.
[0021]
In this way, the gas to be treated is inserted so as to reciprocate in the hydrogen separator, and in this process, only the hydrogen gas contained in the gas to be treated permeates through the hydrogen separation membrane deposited on the inner peripheral surface of the through hole. It will be separated outside the monolith.
Even when the gas to be processed is inserted as described above, the processing area of the hydrogen separator is not impaired because the contact area between the gas to be processed and the hydrogen separation membrane is equal.
Further, since hydrogen separation is performed under high temperature and high pressure conditions, the gas to be treated introduction side is always at a high pressure, and the residual gas does not flow back to the introduction path side.
[0022]
In the above structure, the crown member is a member that hermetically seals the non-supporting end of the hydrogen separator, such as a disk-shaped member having a recess that can be fitted into the hydrogen separator. Can be used.
The material constituting the crown member is not particularly limited as long as it can withstand high temperatures and high pressures during hydrogen separation and can ensure airtightness, and an inorganic adhesive can be used. It is preferable to use a material.
[0023]
The crown member can be joined to the end of the hydrogen separator, or can be joined by screwing or the like, but in any case, it is sealed with a brazing material to ensure airtightness. It is necessary.
In addition, the end face of the hydrogen separator and the crown member should not be brought into close contact with each other and should be joined with a gap that allows the gas to be processed to pass through.
How much gap is to be provided should be determined appropriately depending on the specifications of the hydrogen separator and the hydrogen separation conditions, etc. For example, in the case of a monolith type hydrogen separator, the end face of the hydrogen separator is about several millimeters. What is necessary is just to provide this space | gap.
[0024]
On the other hand, since the support-side end face of the hydrogen separator needs to reliably divide a large number of through holes into two groups of the introduction path side and the recovery path side, the through hole groups may be hermetically isolated by a sealing member. preferable.
At this time, as shown in FIGS. 5 (a) and 5 (b), when the sealing member 92 is positioned on the upper surface of the opening of one through-hole 93a, the introduction path side 94 and the recovery path side 95 cannot be isolated from each other. Since the gas and the separation residual gas are mixed, it is necessary to dispose the sealing member 92 so as to avoid the opening of the through hole 93.
[0025]
As long as the above-described conditions are satisfied, the shape and arrangement method of the sealing member are not particularly limited, and in addition to the flat plate shown in FIG. 6A and the corrugated plate shown in FIG. 6 (c), it may be divided into a center side 96 and an outer peripheral side 97 of the end face of the hydrogen separator 91.
In addition, as shown in FIGS. 6A and 6B, the arrangement pattern of the through holes of the monolith 91 is blocked to secure an arrangement space 98 for the sealing member 92, thereby arranging the sealing member 92. It is also possible to make it easier to install.
[0026]
In addition, although it is preferable that the number of through-holes on the introduction path side and the recovery path side is equal, it is not necessarily required to be strictly divided into two.
As a material constituting the sealing member, ceramic, metal, heat-resistant resin, or the like can be used, and it is preferable to use metal in terms of ensuring high airtightness.
[0027]
【Example】
Next, the present invention will be described in more detail based on the illustrated embodiments, but the present invention is not limited to these embodiments.
In the present invention, even if not particularly mentioned, the joint surfaces between the members are all hermetically joined by a brazing material or the like.
[0028]
(Example 1) A hydrogen separator 1 shown in FIG. 1 is configured by accommodating six monolithic hydrogen separators 5 in a sealed container 4 including a container body 2 and a lid 3. The leg 22 is installed on the floor surface.
The lid 3 is formed with an introduction port 6 and a recovery port 7 communicating with the outside of the container 4, and the container body 2 is formed with a lead-out port 8 communicating with the outside of the container 4. The container body 2 and the lid 3 are formed with outward flanges. A partition plate 11 is hermetically sandwiched between 9 and 10 to partition the inside of the container 4 into an upper chamber 12 and a lower chamber 13.
[0029]
One end of the hydrogen separator 5 is joined to a socket 14 that is fitted and fixed to the partition plate 11, and about half of the members are separated by a flat plate sealing member 20 that is inserted vertically into the socket 14. The through hole (introduction path) communicates with the introduction port 6, and the remaining through hole (recovery path) communicates with the recovery port 7.
Note that the end of the hydrogen separator 5 on the non-supporting side is sealed by a crowning member 15.
[0030]
In this embodiment, the gas to be treated is supplied from the inlet 6 through the collecting pipe 19 and the tubular member 18 into the socket 14 divided by the sealing member 20, and from the upper open end of each hydrogen separator 5. It flows into half of the through holes.
Gas components other than hydrogen in the gas to be treated reach the non-supporting end of the hydrogen separator 5 without passing through the separation membrane, pass through the gap of the crown member 15, and have a lower pressure. It flows into the recovery path. Then, it passes through the hydrogen separator 5 again, and is recovered from the recovery port 7 through the tubular member 16 and the collecting tube 17 from the through hole on the support end side.
On the other hand, the hydrogen gas in the gas to be treated selectively permeates the separation membrane on the inner surface of the through hole, flows out of the hydrogen separator 5, and is guided out of the container 4 from the outlet 8 provided in the lower chamber 13. It is burned.
[0031]
【The invention's effect】
As described above, according to the hydrogen separator of the present invention, even when a monolith type hydrogen separator is used, damage to the hydrogen separator due to the difference in thermal expansion between the hydrogen separator and the sealed container is prevented. Can be prevented.
[Brief description of the drawings]
FIG. 1 is a front sectional view showing one embodiment of a hydrogen separator according to the present invention.
FIG. 2 is a schematic view showing a tube-type hydrogen separator.
FIG. 3 is a schematic view showing a monolith type hydrogen separator.
FIG. 4 is a front sectional view showing an example of a general hydrogen separator.
FIG. 5 is a top view (a) and a schematic perspective view (b) showing an embodiment of a method for disposing a sealing member.
FIGS. 6A and 6B are top views (a), (b), and (c) showing another embodiment of a method for arranging a sealing member. FIGS.
FIGS. 7A and 7B are top views (a) and (b) showing an embodiment in which the arrangement of the through holes of the monolith is blocked.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Hydrogen separator, 2 ... Container main body, 3 ... Cover body, 4 ... Sealed container, 5 ... Hydrogen separator, 6 ... Inlet port, 7 ... Recovery port, 8 ... Outlet port, 9, 10 ... Outward flange, 11 DESCRIPTION OF SYMBOLS ... Partition plate, 12 ... Upper chamber, 13 ... Lower chamber, 14 ... Socket, 15 ... Crowning member, 16 ... Tubular member, 17 ... Collecting pipe, 18 ... Tubular member, 19 ... Collecting pipe, 20 ... Sealing member, 22 ... Leg, 23 ... Drain valve, 34 ... Sealed container, 35 ... Hydrogen separator, 36 ... Inlet port, 37 ... Recovery port, 38 ... Outlet port, 41 ... Partition plate, 42 ... Upper chamber, 54 ... Sealed vessel, 55 ... Hydrogen separator, 56 ... Inlet, 61 ... Partition plate, 62 ... Upper chamber, 71 ... Hydrogen separator, 72 ... Container body, 73 ... Lid, 74 ... Sealed container, 75 ... Hydrogen separator, 76 ... Inlet port, 77 ... Recovery port, 78 ... Outlet port, 79, 80 ... Outward flange, 81 ... Partition plate, 82 ... Upper chamber, 83 ... Chamber 91, hydrogen separator (monolith) 92, sealing member, 93, through-hole, 93 a, 1 through-hole, 94, introduction path side, 95, recovery path side, 96, center side, 97, outer peripheral side, 98 ... Space for arranging sealing member.

Claims (3)

A plurality of hydrogen separators formed by forming a large number of through holes in parallel in the longitudinal direction of the porous substrate, and depositing a hydrogen separation membrane on the inner surface of the through holes;
A sealed container having an inlet for the gas to be treated, a recovery port for recovering the separation residual gas, and an outlet for extracting the separated hydrogen gas;
A hydrogen separator comprising:
One end of the hydrogen separator is fixed to a partition plate provided so as to separate the sealed container into two upper and lower chambers, and is supported in a suspended manner .
A number of through-holes of each hydrogen separator are divided into two through-hole groups of a gas to be treated introduction path and a separation residual gas recovery path, and an unsupported end of each hydrogen separator is formed into a gap by a crowning member. The gas to be treated introduced from the through hole at the support side end of the hydrogen separator is inserted so as to reciprocate in the hydrogen separator and recovered from the through hole at the support side end. By doing so, the hydrogen separation apparatus is allowed to allow a difference in thermal expansion between the hydrogen separator and the sealed container.   The hydrogen separator according to claim 1, wherein the hydrogen separation membrane is made of palladium or an alloy containing palladium. In the upper chamber of the closed container, the introduction port, the gas to be treated introduction path, the recovery port, and the separation residual gas recovery path are connected with a tubular member, and the separated hydrogen gas is recovered from the outlet port provided in the lower chamber. The hydrogen separator according to claim 1 or 2.

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