Membrane assemblies and separation membrane modules

Abstract

The membrane assembly includes a columnar reactor (10), an annular first flange (30) surrounding a first end (10a) of the reactor (10), and a first bonding material (35) interposed between the first flange (30) and the reactor (10). The thermal expansion coefficient of the first flange (30) is greater than that of the first bonding material (35). The thermal expansion coefficient of the first bonding material (35) is greater than that of the reactor (10).

Description

[Technical Field]

[0001] The present invention relates to a membrane assembly and a separation membrane module. [Background technology]

[0002] Conventionally, a separation membrane module has been known that includes a housing and a columnar membrane structure housed in the housing. Examples of the membrane structure include a separation filter configured to separate a predetermined component from a mixed fluid using a separation membrane (see, for example, Patent Document 1), and a reactor configured to separate a product of a conversion reaction from a raw material gas to a liquid fuel using a separation membrane (see, for example, Patent Document 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2018 / 180095 [Patent Document 2] Japanese Patent Application Laid-Open No. 2018-008940 Summary of the Invention [Problem to be solved by the invention]

[0004] However, since it is necessary to provide a permeate side space between the membrane structure and the housing to recover the permeated components that have permeated the separation membrane, it is necessary to prepare a membrane assembly in which flanges are attached to the ends of the membrane structure using a bonding material.

[0005] However, if tensile stress is repeatedly applied to the membrane structure due to differences in the thermal expansion coefficients of the flange, the bonding material, and the membrane structure, the membrane structure may be damaged.

[0006] An object of the present invention is to provide a membrane assembly and a separation membrane module that can suppress damage to the membrane structure. [Means for solving the problem]

[0007] A membrane assembly according to a first aspect of the present invention includes a columnar membrane structure, a first annular flange surrounding a first end of the membrane structure, and a first bonding material interposed between the first flange and the first end. The thermal expansion coefficient of the first flange is greater than that of the first bonding material. The thermal expansion coefficient of the first bonding material is greater than that of the membrane structure.

[0008] The membrane assembly of a second aspect of the present invention is related to the first aspect and includes a second annular flange surrounding the second end of the membrane structure, and a second bonding material interposed between the second flange and the second end. The thermal expansion coefficient of the second flange is greater than that of the second bonding material. The thermal expansion coefficient of the second bonding material is greater than that of the membrane structure.

[0009] A membrane assembly according to a third aspect of the present invention is related to the first or second aspect, wherein the first flange is made of a ceramic material.

[0010] A membrane assembly according to a fourth aspect of the present invention relates to the second aspect, and the second flange is made of a ceramic material.

[0011] A membrane assembly according to a fifth aspect of the present invention relates to the first to fourth aspects, and the membrane structure is a reactor.

[0012] A membrane assembly according to a sixth aspect of the present invention relates to the first to fourth aspects, and the membrane structure is a separation filter.

[0013] A separation membrane module according to a seventh aspect of the present invention comprises the membrane assembly according to any one of the first to sixth aspects and a cylindrical housing that houses the membrane assembly. [Effects of the Invention]

[0014] According to the present invention, it is possible to provide a membrane assembly and a separation membrane module that can suppress damage to the membrane structure. [Brief explanation of the drawings]

[0015] [Figure 1] FIG. 1 is a cross-sectional view of a separation membrane module according to an embodiment. [Figure 2] FIG. 2 is a schematic diagram showing the stresses in a reactor during shutdown. [Figure 3] FIG. 3 is a schematic diagram showing the stresses in the reactor during operation. [Figure 4] FIG. 4 is a cross-sectional view of a separation membrane module according to Modification 2. As shown in FIG. [Figure 5] FIG. 5 is a cross-sectional view taken along line AA in FIG. [Figure 6] FIG. 6 is a cross-sectional view taken along line BB in FIG. [Figure 7] FIG. 7 is a cross-sectional view of a separation membrane module according to Modification 5. As shown in FIG. [Figure 8] FIG. 8 is a cross-sectional view of a separation membrane module according to Modification 5. As shown in FIG. [Figure 9] FIG. 9 is a cross-sectional view of a separation membrane module according to Modification 6. As shown in FIG. [Figure 10] FIG. 10 is a cross-sectional view of a separation membrane module according to the sixth modification. [Figure 11] FIG. 11 is a cross-sectional view of a separation membrane module according to Modification 6. As shown in FIG. [Figure 12] FIG. 12 is a cross-sectional view of a separation membrane module according to the seventh modification. [Figure 13] FIG. 13 is a cross-sectional view of a separation membrane module according to the seventh modification. [Figure 14] FIG. 14 is a cross-sectional view of a separation membrane module according to Modification 8. As shown in FIG. [Figure 15] FIG. 15 is a cross-sectional view of a separation membrane module according to Modification 8. As shown in FIG. [Figure 16] FIG. 16 is a cross-sectional view of a separation membrane module according to Modification 8. As shown in FIG. DETAILED DESCRIPTION OF THE INVENTION

[0016] (Separation membrane module 1) A separation membrane module 1 according to an embodiment will now be described. FIG. 1 is a cross-sectional view schematically showing the configuration of the separation membrane module 1.

[0017] 1, the separation membrane module 1 includes a reactor 10, a housing 20, a first flange 30, and a second flange 40. The reactor 10 is an example of the "membrane structure" according to the present invention.

[0018] [Reactor 10] The reactor 10 is accommodated in a housing 20. The reactor 10 is formed in a columnar shape extending in the longitudinal direction. The outer shape of the reactor 10 is not particularly limited, but may be, for example, a circular cylinder, an elliptical cylinder, or a polygonal cylinder.

[0019] The reactor 10 is a so-called membrane reactor for converting a raw material gas into a liquid fuel. The raw material gas contains at least hydrogen and carbon oxides. At least one of carbon monoxide and carbon dioxide can be used as the carbon oxide. The raw material gas may be a so-called synthesis gas (Syngas). The liquid fuel is a fuel that is in a liquid state at room temperature and pressure, or a fuel that can be liquefied under pressure at room temperature. Examples of fuels that are in a liquid state at room temperature and pressure include methanol, ethanol, and C n H 2(m-2n) (m is an integer less than 90, and n is an integer less than 30), and mixtures thereof. Examples of fuels that can be liquefied under pressure at room temperature include propane, butane, and mixtures thereof.

[0020] For example, the reaction formula (1) when methanol is synthesized by catalytic hydrogenation of a raw material gas containing hydrogen and carbon dioxide in the presence of a catalyst is as follows: CO2 + 3H2 ⇔ CH3OH + H2O (1)

[0021] The above reaction is an equilibrium reaction, and the reactor 10 can shift the reaction equilibrium toward the product side by separating water vapor, which is one of the products of the conversion reaction. To increase the conversion efficiency and reaction rate, the conversion reaction is preferably carried out under high temperature and pressure (e.g., 180°C or higher, 2 MPa or higher). The liquid fuel is in a gaseous state when synthesized and remains in this state at least until it flows out of the reactor 10. The reactor 10 preferably has heat resistance and pressure resistance suitable for the synthesis conditions of the desired liquid fuel.

[0022] The reactor 10 according to this embodiment is a so-called tubular type. As shown in FIG. 1, the reactor 10 has an outer peripheral surface F1, a first end surface F2, and a second end surface F3. The outer peripheral surface F1 is a side surface of the cylindrical reactor 10. The outer peripheral surface F1 is connected to the first end surface F2 and the second end surface F3. The first end surface F2 is one end surface of the cylindrical reactor 10. A first opening T1 is formed in the first end surface F2. A raw material gas flows into the reactor 10 through the first opening T1. The second end surface F3 is the other end surface of the cylindrical reactor 10. A second opening T2 is formed in the second end surface F3. A liquid fuel flows out of the reactor 10 through the second opening T2.

[0023] The reactor 10 has a first end 10a and a second end 10b. The first end 10a is one end of the reactor 10 in the longitudinal direction. The first end 10a includes the first end face F2 described above. The second end 10b is the other end of the reactor 10 in the longitudinal direction. The second end 10b includes the second end face F3 described above.

[0024] Here, the reactor 10 is composed of a porous support 11, a separation membrane 12, a catalyst 13, and a catalyst stopper 14.

[0025] The porous support 11 is formed in a cylindrical shape extending in the longitudinal direction. The porous support 11 is made of a porous material. As the porous material, ceramic materials, metal materials, resin materials, and composite materials thereof can be used, and ceramic materials are particularly suitable. As aggregates for ceramic materials, alumina (Al2O3), titania (TiO2), mullite (Al2O3·SiO2), cerium dioxide, and cordierite (Mg2Al4Si5O 18 ), and composite materials containing two or more of these can be used, with alumina being preferred in consideration of availability, clay stability, and corrosion resistance. As the inorganic binder for the ceramic material, at least one of titania, mullite, sinterable alumina, silica, glass frit, clay minerals, and sinterable cordierite can be used. However, the ceramic material does not necessarily need to contain an inorganic binder.

[0026] The average pore diameter of the porous support 11 can be 5 μm or more and 25 μm or less. The average pore diameter of the porous support 11 can be measured by mercury intrusion porosimetry. The porosity of the porous support 11 can be 25% or more and 50% or less. The average particle diameter of the porous material can be 1 μm or more and 100 μm or less. The average particle diameter is the arithmetic mean value of the maximum diameters of 30 particles (randomly selected) measured by cross-sectional microstructure observation using a scanning electron microscope (SEM).

[0027] The separation membrane 12 is supported by a porous support 11. The separation membrane 12 is formed in a cylindrical shape extending in the longitudinal direction. Inside the separation membrane 12 is a non-permeation side space S1 to which a raw material gas is supplied. The non-permeation side space S1 is a space between a first opening T1 and a second opening T2. In this embodiment, the separation membrane 12 is disposed on the inner surface of the porous support 11, but it may also be disposed on the outer surface of the porous support 11.

[0028] The separation membrane 12 allows water vapor, which is one of the products of the conversion reaction from the feed gas to liquid fuel, to pass through, thereby utilizing the equilibrium shift effect to shift the reaction equilibrium of the above formula (1) to the product side.

[0029] The separation membrane 12 has a conductivity of 100 nmol / (s·Pa·m 2 The water vapor permeability coefficient can be determined by a known method (see Ind. Eng. Chem. Res., 40, 163-175 (2001)).

[0030] The separation membrane 12 preferably has a separation factor of 100 or more. The larger the separation factor, the easier it is for water vapor to permeate and the less permeable it is for components other than water vapor (such as hydrogen, carbon oxides, and liquid fuels). The separation factor can be determined by a known method (see Fig. 1 in "Separation and Purification Technology 239 (2020) 116533").

[0031] An inorganic membrane can be used as the separation membrane 12. Inorganic membranes are preferred because they are heat-resistant, pressure-resistant, and water vapor-resistant. Examples of inorganic membranes include zeolite membranes, silica membranes, alumina membranes, and composite membranes of these. In particular, an LTA-type zeolite membrane, in which the molar ratio (Si / Al) of silicon element (Si) to aluminum element (Al) is 1.0 or more and 3.0 or less, is preferred because of its excellent water vapor permeability.

[0032] The catalyst 13 is disposed inside the separation membrane 12, i.e., in the non-permeation side space S1. The catalyst 13 is preferably packed in the non-permeation side space S1, but may also be disposed in the form of layers or islands on the surface of the separation membrane 12. The catalyst 13 promotes the conversion reaction from the feed gas to the liquid fuel shown in the above formula (1).

[0033] Any known catalyst suitable for a conversion reaction from a raw material gas to a liquid fuel can be used as the catalyst 13. Examples of the catalyst 13 include metal catalysts (copper, palladium, etc.), oxide catalysts (zinc oxide, zirconia, gallium oxide, etc.), and catalysts made by combining these (copper-zinc oxide, copper-zinc oxide-alumina, copper-zinc oxide-chromium oxide-alumina, copper-cobalt-titania, and catalysts made by modifying these with palladium, etc.).

[0034] The catalyst stopper 14 is attached to the second end face F3. The catalyst stopper 14 is arranged to cover the second opening T2 formed in the second end face F3. The catalyst stopper 14 prevents the catalyst 13 from leaking out through the second opening T2. The catalyst stopper 14 has a configuration that prevents the catalyst 13 from leaking out while not impeding the outflow of liquid fuel. The catalyst stopper 14 may be, for example, a mesh member or a perforated plate.

[0035] However, if leakage of the catalyst 13 is unlikely to occur (for example, if the catalyst 13 is arranged in a layer or island form on the surface of the separation membrane 12), the reactor 10 does not need to have the catalyst stopper 14.

[0036] In the reactor 10, the raw material gas supplied to the non-permeation side space S1 is converted into liquid fuel by the action of the catalyst 13, and water vapor, which is one of the products of the conversion reaction, passes through the separation membrane 12 and the porous support 11 and is separated into the permeation side space S2 described later.

[0037] [Housing 20] The housing 20 is formed into a cylindrical shape as a whole. The housing 20 accommodates the reactor 10. The housing 20 has a structure that can withstand a conversion reaction under high temperature and high pressure (e.g., 180°C or higher, 2 MPa or higher). When the source gas and / or the sweep gas contains hydrogen, it is preferable that the material of the housing 20 is resistant to hydrogen embrittlement. The housing 20 can be mainly made of a metal material (stainless steel, etc.).

[0038] As shown in FIG. 1, the housing 20 is composed of a cylindrical main body 21, a first end plate 22, and a second end plate .

[0039] The cylindrical body 21 is formed in a cylindrical shape extending in the longitudinal direction. Both ends of the cylindrical body 21 are expanded in diameter in the shape of flanges.

[0040] The cylindrical body 21 has an inner circumferential surface G1, a first end surface G2, a second end surface G3, a sweep gas supply port T3, and a sweep gas discharge port T4.

[0041] The inner peripheral surface G1 faces the outer peripheral surface F1 of the reactor 10, but is spaced apart from the outer peripheral surface F1. The gap between the inner peripheral surface G1 and the outer peripheral surface F1 is a permeation side space S2 for recovering water vapor, which is one of the products of the conversion reaction.

[0042] An annular first notch H1 is formed at one end of the inner circumferential surface G1. An annular first elastic member 26a is disposed in the first notch H1. The first elastic member 26a can be, for example, an O-ring made of expanded graphite or rubber. The first elastic member 26a is pressed by a first pressing member 24 inserted into the first notch H1 and comes into close contact with a first flange 30 (described below). This seals the gap between the tube main body 21 and the first flange 30. The first pressing member 24 is fixed to the first end surface G2 of the tube main body 21 by a bolt or the like. In this embodiment, the first pressing member 24 has an L-shaped cross section.

[0043] An annular second notch H2 is formed at the other end of the inner circumferential surface G1. An annular second elastic member 26b is disposed in the second notch H2. The second elastic member 26b may be, for example, an O-ring made of expanded graphite or rubber. The second elastic member 26b is pressed by a second pressing member 25 inserted into the second notch H2 and comes into close contact with a second flange 40 (described later). This seals the gap between the tube main body 21 and the second flange 40. The second pressing member 25 is fixed to a second end surface G3 of the tube main body 21 by a bolt or the like. In this embodiment, the second pressing member 25 has an L-shaped cross section.

[0044] A first annular recess H3 is formed in the first end surface G2. A third elastic member 26c is disposed in the first recess H3. For example, an O-ring made of expanded graphite or rubber can be used as the third elastic member 26c. The third elastic member 26c is in close contact with the first end plate 22.

[0045] A second annular recess H4 is formed in the second end face G3. A fourth elastic member 26d is disposed in the second recess H4. For example, an O-ring made of expanded graphite or rubber can be used as the fourth elastic member 26d. The fourth elastic member 26d is in close contact with the second end plate 23.

[0046] The sweep gas inlet T3 and the sweep gas outlet T4 are connected to the permeate side space S2. The sweep gas is supplied from the sweep gas inlet T3 to the permeate side space S2. The sweep gas takes in water vapor in the permeate side space S2 and absorbs the reaction heat associated with the conversion reaction. The sweep gas is discharged together with water vapor from the sweep gas outlet T4. Hydrogen and / or carbon oxides can be used as the sweep gas. Alternatively, an inert gas (e.g., nitrogen) or air can be used as the sweep gas. In this embodiment, the sweep gas inlet T3 and the sweep gas outlet T4 are diagonally opposed to each other in a cross-sectional view, but the respective positions of the sweep gas inlet T3 and the sweep gas outlet T4 can be changed as appropriate.

[0047] The first end plate 22 is an annular plate member. The central portion of the first end plate 22 has an expanded diameter like a flange. The first end plate 22 has a first opposing surface J1. The first opposing surface J1 faces a first end face F2 of the reactor 10 and an end face K1 of a first flange 30, which will be described later.

[0048] In this specification, when two surfaces are "opposed" it means that at least a portion of each of the two surfaces directly faces each other without any other member in between.

[0049] However, the first opposing surface J1 does not have to face the first end face F2 of the reactor 10. The first opposing surface J1 abuts against the first end face G2 of the cylindrical main body 21. An annular third recess H5 is formed in the first opposing surface J1. The third recess H5 accommodates a portion of the first pressing member 24 that protrudes from the first end face G2.

[0050] First end plate 22 is connected to tube main body 21 by a plurality of fixing members 27. Fixing members 27 are formed, for example, by bolts and nuts. First end plate 22 is in close contact with third elastic member 26c. This creates a seal between tube main body 21 and first end plate 22.

[0051] The second end plate 23 is an annular plate member. The central portion of the second end plate 23 has an expanded diameter in the shape of a flange. The second end plate 23 has a second opposing surface J2. The second opposing surface J2 faces the second end face F3 of the reactor 10 and the end face K2 of the second flange 40 (described later). However, the second opposing surface J2 does not necessarily face the second end face F3 of the reactor 10. The second opposing surface J2 abuts against the second end face G3 of the cylindrical main body 21. An annular fourth recess H6 is formed in the second opposing surface J2. The fourth recess H6 accommodates the portion of the second pressing member 25 that protrudes from the second end face G3.

[0052] The second end plate 23 is connected to the tube main body 21 by a plurality of fixing members 28. The fixing members 28 are formed, for example, by bolts and nuts. The second end plate 23 is in close contact with the fourth elastic member 26d. This creates a seal between the tube main body 21 and the second end plate 23.

[0053] [First flange 30] The first flange 30 is attached to the reactor 10. The first flange 30 functions as a spacer for forming a permeate-side space S2 between the reactor 10 and the cylindrical main body 21. The first flange 30 is formed in an annular shape. The first flange 30 surrounds the first end 10a of the reactor 10. The first flange 30 is fitted into one end of the cylindrical main body 21. The first flange 30 supports the first end 10a of the reactor 10 at a position separated from the cylindrical main body 21. This forms a permeate-side space S2 between the reactor 10 and the cylindrical main body 21.

[0054] The first flange 30 has an end face K1 and an outer peripheral surface L1. The end face K1 is the longitudinally outer surface of the first flange 30. The end face K1 faces the first opposing surface J1 of the first end plate 22. At least a portion of the end face K1 may abut against the first opposing surface J1. In this embodiment, the end face K1 is flat. The outer peripheral surface L1 is the radially outer surface of the first flange 30. The outer peripheral surface L1 faces the inner peripheral surface G1 of the tube main body 21 and is in close contact with the first elastic member 26a. The outer peripheral surface L1 may abut against the inner peripheral surface G1.

[0055] The first flange 30 is made of a dense ceramic material. Examples of ceramic materials that can be used include alumina, zirconia, silicon carbide, aluminum nitride, cordierite, and composite materials containing two or more of these. The first flange 30 must be airtight and liquidtight. Therefore, the porosity of the first flange 30 is preferably 10.0% or less, and more preferably 5.0% or less.

[0056] A first bonding material 35 is inserted in the gap between the first flange 30 and the reactor 10. The first bonding material 35 bonds the first flange 30 and the reactor 10. The first bonding material 35 only needs to ensure the bonding strength between the first flange 30 and the reactor 10, and is disposed in at least a part of the gap between the first flange 30 and the reactor 10. The assembly of the first flange 30 and the reactor 10 bonded by the first bonding material 35 is the "membrane assembly" according to the present invention.

[0057] The first bonding material 35 may be made of crystallized glass, amorphous glass, brazing material, or ceramics, and in consideration of heat resistance and pressure resistance, crystallized glass is particularly preferable.

[0058] Examples of glass-ceramics that can be used include SiO2-B2O3-based, SiO2-CaO-based, SiO2-Al2O3-based, SiO2-MgO-based, SiO2-ZnO-BaO-based, SiO2-B2O3-CaO-based, or SiO2-MgO-CaO-based, SiO2-Al2O3-B2O3-based, and SiO2-MgO-Al2O3-based glass-ceramics. In this specification, glass-ceramics refers to glass in which the ratio of the "volume occupied by the crystalline phase" to the total volume (degree of crystallinity) is 60% or more, and the ratio of the "volume occupied by the amorphous phase and impurities" to the total volume is less than 40%.

[0059] [Second flange 40] The second flange 40 is attached to the reactor 10. The second flange 40 is disposed on the opposite side of the first flange 30. The second flange 40 functions as a spacer for forming a permeate side space S2 between the reactor 10 and the cylindrical body 21. The second flange 40 is formed in an annular shape. The second flange 40 surrounds the second end 10b of the reactor 10. The second flange 40 is fitted into the other end of the cylindrical body 21. The second flange 40 supports the second end 10b of the reactor 10 at a position spaced apart from the cylindrical body 21.

[0060] The second flange 40 has an end face K2 and an outer peripheral surface L2. The end face K2 is the longitudinally outer surface of the second flange 40. The end face K2 faces the second opposing surface J2 of the second end plate 23. At least a portion of the end face K2 may abut against the second opposing surface J2. In this embodiment, the end face K2 is flat. The outer peripheral surface L2 is the radially outer surface of the second flange 40. The outer peripheral surface L2 faces the inner peripheral surface G1 of the tube main body 21 and is in close contact with the second elastic member 26b. The outer peripheral surface L2 may abut against the inner peripheral surface G1.

[0061] The second flange 40 is made of a dense ceramic material. Examples of ceramic materials that can be used include alumina, zirconia, silicon carbide, aluminum nitride, cordierite, and composite materials containing two or more of these. The second flange 40 must be airtight and liquidtight. Therefore, the porosity of the second flange 40 is preferably 10.0% or less, and more preferably 5.0% or less.

[0062] A second bonding material 45 is interposed in the gap between the second flange 40 and the reactor 10. The second bonding material 45 bonds the second flange 40 and the reactor 10. The second bonding material 45 is required only to ensure the bonding strength between the second flange 40 and the reactor 10, and is disposed in at least a part of the gap between the second flange 40 and the reactor 10. The assembly of the second flange 40 and the reactor 10 bonded by the second bonding material 45 is the "membrane assembly" according to the present invention. As the second bonding material 45, crystallized glass, amorphous glass, brazing material, ceramics, or the like can be used, and crystallized glass is particularly preferable in consideration of heat resistance and pressure resistance.

[0063] [Relationship between thermal expansion coefficients] The thermal expansion coefficient of the first flange 30 is larger than that of the first bonding material 35, and the thermal expansion coefficient of the first bonding material 35 is larger than that of the reactor 10. That is, the relationship of first flange 30 > first bonding material 35 > reactor 10 holds true regarding the thermal expansion coefficient. Therefore, compressive stress is applied to the reactor 10 from the first flange 30 and the first bonding material 35 at room temperature, and the compressive stress applied to the reactor 10 from the first flange 30 and the first bonding material 35 is reduced at high temperatures during operation. Therefore, even if thermal cycles associated with the operation and shutdown of the separation membrane module 1 are repeated, repeated application of tensile stress from the first flange 30 and the first bonding material 35 to the reactor 10 can be suppressed, thereby suppressing damage to the reactor 10. Specifically, this is as follows.

[0064] The process of assembling the separation membrane module 1 includes a step of preparing a membrane assembly in which the first and second flanges 30, 40 are joined to the reactor 10, and a step of housing the membrane assembly in the housing 20.

[0065] The process for fabricating a membrane assembly includes a first step of forming a green body of a bonding material, a second step of attaching flanges, and a third step of heating the green body of the bonding material. In the first step, a green body of the first bonding material 35 is formed at the first end 10a of the reactor 10, and a green body of the second bonding material 45 is formed at the second end 10b of the reactor 10. In the second step, the first flange 30 is attached to surround the green body of the first bonding material 35, and the second flange 40 is attached to surround the green body of the second bonding material 45. In the third step, the green bodies of the first and second bonding materials 35, 45 are heated to cause crystal growth or melting, and then cooled to room temperature to form the first and second bonding materials 35, 45. This completes the membrane assembly in which the first and second flanges 30, 40 are bonded to the reactor 10 via the first and second bonding materials 35, 45.

[0066] Next, the process of accommodating the membrane assembly includes a fourth step of inserting the membrane assembly, a fifth step of attaching the elastic members, and a sixth step of connecting the end plates. In the fourth step, the membrane assembly is inserted into the tube body 21, and then both ends of the membrane assembly are aligned. In the fifth step, the first and second elastic members 26a and 26b fitted into the first and second notches H1 and H2 of the tube body 21 are pressed by the first and second pressing members 24 and 25, and the third and fourth elastic members 26c and 26d are fitted into the first and second recesses H3 and H4 of the tube body 21. In the sixth step, the first end plate 22 is connected to the tube body 21 by the fixing member 27, and the second end plate 23 is connected to the tube body 21 by the fixing member 28. This completes the separation membrane module 1 in which the membrane assembly is accommodated in the housing 20.

[0067] Here, when the molded body of the first bonding material 35 is heated in the third step, no stress is generated in the first flange 30, the first bonding material 35, and the reactor 10. When the temperature is subsequently lowered to room temperature, the thermal expansion coefficient of the first flange 30 is larger than that of the first bonding material 35, and the thermal expansion coefficient of the first bonding material 35 is larger than that of the reactor 10. Therefore, the first flange 30 contracts more than the first bonding material 35, and the first bonding material 35 contracts more than the reactor 10. Therefore, at room temperature, a compressive stress is applied to the reactor 10 by the first flange 30 and the first bonding material 35.

[0068] Therefore, when the completed separation membrane module 1 is repeatedly operated and stopped, compressive stress is applied to the reactor 10 from the first flange 30 and the first bonding material 35 at room temperature during stoppage, as shown in Fig. 2, and the compressive stress applied to the reactor 10 from the first flange 30 and the first bonding material 35 is reduced at high temperatures during operation, as shown in Fig. 3. Therefore, even if the thermal cycle associated with the operation and stoppage of the separation membrane module 1 is repeated, it is possible to prevent tensile stress from being applied to the reactor 10 from the first flange 30 and the first bonding material 35. Generally, ceramics have the properties of being weak against tensile stress but strong against compressive stress, and therefore damage to the ceramic reactor 10 can be prevented.

[0069] The thermal expansion coefficient of the first flange 30 can be adjusted by changing the material, combining materials, changing the material composition, and changing the porosity. The thermal expansion coefficient of the first bonding material 35 can be adjusted by changing the material, combining materials, changing the material composition, and changing the porosity. The thermal expansion coefficient of the reactor 10 can be adjusted by changing the material, combining materials, changing the material composition, and changing the porosity.

[0070] Furthermore, it is preferable that the thermal expansion coefficient of the second flange 40 is larger than that of the second bonding material 45, and that the thermal expansion coefficient of the second bonding material 45 is larger than that of the reactor 10. That is, it is preferable that the relationship of the thermal expansion coefficients is second flange 40 > second bonding material 45 > reactor 10. This has the same effect as when the relationship of the thermal expansion coefficients is first flange 30 > first bonding material 35 > reactor 10, and can prevent the reactor 10 from being damaged.

[0071] The thermal expansion coefficient of the second flange 40 can be adjusted by changing the material, combining materials, changing the material composition, and changing the porosity. The thermal expansion coefficient of the second bonding material 45 can be adjusted by changing the material, combining materials, changing the material composition, and changing the porosity. The thermal expansion coefficient of the reactor 10 can be adjusted by changing the material, combining materials, changing the material composition, and changing the porosity.

[0072] The thermal expansion coefficient is the ratio of the expansion or contraction length specific to a material to a temperature change. The thermal expansion coefficient can be measured, for example, by a method conforming to JIS R 1618:1994. The unit of the thermal expansion coefficient is ppm / K. In this specification, the thermal expansion coefficient means the thermal expansion coefficient at 40°C to 800°C. The higher temperature (i.e., 800°C) may be changed depending on the crystallization temperature of the first bonding material 35 or the second bonding material 45. The crystallization temperature of the first bonding material 35 or the second bonding material 45 can be changed as appropriate.

[0073] (Modification of the embodiment) Although the embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the gist of the invention.

[0074] [Variation 1] In the above embodiment, the reactor 10 is used as the membrane structure, but a separation filter can also be used as the membrane structure. The separation filter has the same configuration as the reactor 10, except that a separation membrane that allows the permeation of desired components contained in the mixed fluid is used instead of the separation membrane 12 that allows the permeation of water vapor, and that the separation filter does not include the catalyst 13. Furthermore, in the present invention, even if a separation filter is used as the membrane structure, it is assumed that it will be used under high temperature and high pressure conditions.

[0075] When a separation filter is used as the membrane structure, no reaction heat is generated and there is little need for temperature control. Therefore, the components that have permeated the separation membrane may be discharged from the sweep gas outlet T4 by reducing the pressure on the sweep gas outlet T4 side more than on the sweep gas supply port T3 side.

[0076] [Variation 2] In the above embodiment, the reactor 10, which is an example of a membrane structure, is of a tubular type, but it may also be of a monolith type. The monolith type refers to a shape having multiple cells penetrating in the longitudinal direction, and is a concept that includes a honeycomb type.

[0077] Fig. 4 is a cross-sectional view that schematically shows the configuration of a separation membrane module 1a that includes a monolithic reactor 100. However, in Fig. 4, only the reactor 100 is shown in side view.

[0078] The separation membrane module 1a is the same as the separation membrane module 1 according to the above embodiment, except that it further includes a flow stopper 50 and a reactor 100 instead of the reactor 10. Note that the catalyst stopper 14 is also an optional configuration in the reactor 100.

[0079] The flow stopper 50 is formed in an annular shape. The flow stopper 50 is disposed between the reactor 100 and the housing 20. The flow stopper 50 divides the gap between the reactor 100 and the housing 20 into a first permeate side space S21 and a second permeate side space S22. The flow stopper 50 prevents the sweep gas from flowing directly between the first permeate side space S21 and the second permeate side space S22. The flow stopper 50 need not seal the space between the reactor 100 and the housing 20 as long as it can directly prevent the flow of the sweep gas. The flow stopper 50 can be made of, for example, expanded graphite, rubber, resin, metal, etc.

[0080] The reactor 100 has a plurality of first flow paths 15, a plurality of second flow paths 16, a first slit 17, and a second slit .

[0081] The first flow path 15 passes through the reactor 100 in the longitudinal direction. The first flow path 15 opens to the first and second end faces F2, F3. The separation membrane 12 described above is formed on the inner surface of the first flow path 15. The inside of the separation membrane 12 is the non-permeation side space S1. The catalyst 13 described above is disposed in the non-permeation side space S1.

[0082] The second flow path 16 is formed inside the reactor 100. The second flow path 16 extends along the longitudinal direction. The second flow path 16 is closed at the first and second end faces F2, F3.

[0083] The first slits 17 are formed in the first end 100a of the reactor 100. The first slits 17 radially penetrate each second flow path 16 and open to the outer peripheral surface F1. Therefore, the first slits 17 communicate with each second flow path 16 and the first permeate side space S21.

[0084] The second slits 18 are formed at the second end 100b of the reactor 100. The second slits 18 radially penetrate each second flow path 16 and open to the outer peripheral surface F1. Therefore, the second slits 18 communicate with each second flow path 16 and the second permeate side space S22.

[0085] When a raw material gas is supplied to the first flow path 15, the raw material gas is converted into a liquid fuel by the action of the catalyst 13, and water vapor, which is one of the products of the conversion reaction, passes through the separation membrane 12 and flows into the second flow path 16. The water vapor that has flowed into the second flow path 16 is taken in by the sweep gas that flows from the sweep gas supply port T3 through the second permeate side space S22 and the second slit 18 into the second flow path 16, and then passes through the first slit 17 and the first permeate side space S21 and is discharged to the outside from the sweep gas discharge port T4.

[0086] Here, Fig. 5 is a cross-sectional view taken along line AA in Fig. 4. As shown in Fig. 5, the first slit 17 linearly penetrates the interior of the reactor 100 and opens to both sides of the reactor 100. The first slit 17 has two openings formed in the outer peripheral surface F1. The sweep gas that flows out from each of the two openings of the first slit 17 into the first permeate side space S21 passes through the first permeate side space S21 and is discharged to the outside from the sweep gas outlet T4.

[0087] Here, the first extension direction in which the first slits 17 extend inside the reactor 100 is preferably inclined or perpendicular to the discharge direction of the sweep gas discharged from the sweep gas discharge port T4 to the outside. Specifically, the angle θ1 of the first extension direction with respect to the discharge direction is preferably 45 degrees or more and 135 degrees or less. This makes it possible to suppress bias in the gas flow from each opening of the first slits 17 to the sweep gas discharge port T4, thereby suppressing bias in the sweep gas flow in the first permeate side space S21.

[0088] 6 is a cross-sectional view taken along the line BB in FIG. 4. As shown in FIG. 6, the second slit 18 penetrates the interior of the reactor 100 in a straight line and opens to both sides of the reactor 100. The second slit 18 has two openings formed in the outer peripheral surface F1. The sweep gas supplied from the sweep gas supply port T3 to the second permeate side space S22 passes through the second permeate side space S22 and flows into each of the two openings of the second slit 18.

[0089] Here, the second extension direction in which the second slits 18 extend inside the reactor 100 is preferably inclined or perpendicular to the supply direction of the sweep gas supplied from the sweep gas supply port T3 to the second permeate side space S22. Specifically, the angle θ2 of the second extension direction with respect to the supply direction is preferably 45 degrees or more and 135 degrees or less. This makes it possible to suppress bias in the gas flow from the sweep gas supply port T3 to each opening of the second slits 18, thereby suppressing bias in the sweep gas flow in the second permeate side space S22.

[0090] [Variation 3] In the above embodiment, the separation membrane 12 is in contact with the catalyst 13. However, a buffer layer may be interposed between the separation membrane 12 and the catalyst 13. The buffer layer physically separates the catalyst 13 from the separation membrane 12, thereby preventing cracks from occurring in the separation membrane 12 originating from the contact point with the catalyst 13 when the catalyst becomes hot due to the heat of reaction. The buffer layer may be made of a ceramic material or an organic polymer material. Examples of ceramic materials that can be used include silica, alumina, and chromia. Examples of organic polymer materials that can be used include PTFE, PVA, and PEG.

[0091] [Variation 4] In the above embodiment, the separation membrane 12 is permeable to water vapor, which is one of the products of the conversion reaction from the feed gas to the liquid fuel. However, this is not limited to this. The separation membrane 12 may also be permeable to the liquid fuel itself, which is produced by the conversion reaction from the feed gas to the liquid fuel. In this case, too, the reaction equilibrium of the above formula (1) can be shifted toward the product side.

[0092] Furthermore, when separation membrane 12 allows liquid fuel to permeate, the reaction equilibrium can be shifted to the product side even when liquid fuel is produced by a reaction that does not produce water vapor (for example, 2H2 + CO ⇔ CH3OH).

[0093] [Variation 5] In the separation membrane module 1 according to the above embodiment (see FIG. 1), the sweep gas supply port T3 and the sweep gas outlet T4 are arranged diagonally opposite each other in a side view, and the sweep gas flows from the sweep gas supply port T3 toward the sweep gas outlet T4, but this is not limited to this.

[0094] For example, as shown in Fig. 7, the sweep gas supply port T3 and the sweep gas discharge port T4 may be arranged on the same side of the reactor 10 in a side view, or a rectifying plate 20a may be provided to close a part of the gap between the reactor 10 and the housing 20. Although three rectifying plates 20a are provided in Fig. 7, the number of rectifying plates 20a may be one, two, or four or more. The position of the rectifying plate 20a can be set as appropriate.

[0095] 8, the housing 20 does not have a sweep gas supply port T3, and a sweep gas does not have to be supplied into the housing 20. In this case, the product separated by the separation membrane 12 of the reactor 10 flows out of the housing 20 through a sweep gas outlet T4. The position of the sweep gas outlet T4 can be set appropriately.

[0096] The configurations of FIGS. 7 and 8 are also applicable to the case where a separation filter is used as the membrane structure instead of the reactor 10.

[0097] [Variation 6] In the separation membrane module 1 (see FIG. 1) according to the above embodiment, only one reactor 10 is accommodated in the housing 20, but this is not limiting.

[0098] For example, as shown in FIG. 9, a plurality of reactors 10 may be housed within a housing 20.

[0099] 10, a rectifying plate 20a may be provided to close a part of the gap between the reactor 10 and the housing 20. In FIG. 10, three rectifying plates 20a are provided, but the number of rectifying plates 20a may be one, two, or four or more. The position of the rectifying plate 20a can be set appropriately. Note that, as shown in FIG. 10, the sweep gas supply port T3 and the sweep gas exhaust port T4 may be arranged on the same side of the reactor 10 in a side view.

[0100] 11, the housing 20 does not have a sweep gas supply port T3, and a sweep gas does not have to be supplied into the housing 20. In this case, the product separated by the separation membrane 12 of the reactor 10 flows out of the housing 20 through a sweep gas outlet T4. The position of the sweep gas outlet T4 can be set appropriately.

[0101] The configurations of FIGS. 9 to 11 are also applicable to the case where a separation filter is used as the membrane structure instead of the reactor 10.

[0102] [Variation 7] In the separation membrane module 1a according to the second modification (see FIG. 4), the sweep gas supply port T3 and the sweep gas discharge port T4 are arranged diagonally opposite each other in a side view, but this is not limiting.

[0103] For example, as shown in FIG. 12, the sweep gas supply port T3 and the sweep gas exhaust port T4 may be arranged on the same side of the reactor 100 in a side view, or a rectifying plate 20b may be provided to block a portion of the gap between the reactor 100 and the housing 20. In FIG. 12, one rectifying plate 20b is provided on each side of the flow stopper 90. The rectifying plate 20b on the sweep gas supply port T3 side divides the space on the sweep gas supply port T3 side into a space where the sweep gas mainly flows into the second slit 18 of the reactor 100 and a space where the sweep gas flows in from the side of the reactor 100. The rectifying plate 20b on the sweep gas exhaust port T4 side divides the space on the sweep gas exhaust port T4 side into a space where the sweep gas mainly flows out from the first slit 17 of the reactor 100 and a space where the sweep gas flows out from the side of the reactor 100. However, the number and positions of the rectifying plates 20b can be set as appropriate. Also, a portion of the sweep gas may pass through the inside of the flow stopper 90 .

[0104] 13, the housing 20 does not have a sweep gas supply port T3, and a sweep gas does not have to be supplied into the housing 20. In this case, the product separated by the separation membrane 12 of the reactor 100 flows out of the housing 20 through a sweep gas outlet T4. The position of the sweep gas outlet T4 can be set as appropriate.

[0105] The configurations of FIGS. 12 and 13 are also applicable to the case where a separation filter is used as the membrane structure instead of the reactor 100.

[0106] [Variation 8] In the separation membrane module 1a according to the second modification (see FIG. 4), only one reactor 100 is accommodated in the housing 20, but the present invention is not limited to this.

[0107] For example, as shown in FIG. 14, a plurality of reactors 100 may be housed within the housing 20.

[0108] 15, a straightening plate 20b may be provided to block a portion of the gap between the reactor 100 and the housing 20. In FIG. 15, one straightening plate 20b is provided on each side of the flow stopper 90. The straightening plate 20b on the sweep gas supply port T3 side divides the space on the sweep gas supply port T3 side into a space where the sweep gas mainly flows into the second slit 18 of the reactor 100 and a space where the sweep gas flows in from the side of the reactor 100. The straightening plate 20b on the sweep gas outlet port T4 side divides the space on the sweep gas outlet port T4 side into a space where the sweep gas mainly flows out from the first slit 17 of the reactor 100 and a space where the sweep gas flows out from the side of the reactor 100. However, the number and positions of the straightening plates 20b can be set as appropriate. A portion of the sweep gas may pass through the inside of the flow stopper 90. As shown in FIG. 15, the sweep gas supply port T3 and the sweep gas exhaust port T4 may be disposed on the same side of the reactor 100 in a side view.

[0109] 16, the housing 20 does not have a sweep gas supply port T3, and a sweep gas does not have to be supplied into the housing 20. In this case, the product separated by the separation membrane 12 of the reactor 100 flows out of the housing 20 through a sweep gas outlet T4. The position of the sweep gas outlet T4 can be set as appropriate.

[0110] 14 to 16 can also be applied to a case where a separation filter is used as the membrane structure instead of the reactor 100. [Explanation of symbols]

[0111] 1 Separation membrane module 10 Reactor 10a 1st end 10b 2nd end 20. Housing G1 Inner surface J1 First opposing surface J2 2nd facing surface 21 Cylinder body 22 First end plate 23 Second end plate 30 No. 1 Furuno K1 end face L2 outer surface 40 No. 2 Furuno K2 end face L2 outer surface 35 1st bonding material 45 Second bonding material

Claims

1. A columnar membrane structure; a first annular flange surrounding a first end of the membrane structure; a first bonding material interposed between the first flange and the membrane structure; Equipped with The thermal expansion coefficient of the first flange is greater than the thermal expansion coefficient of the first bonding material, The thermal expansion coefficient of the first bonding material is greater than the thermal expansion coefficient of the membrane structure. Membrane assembly.

2. a second annular flange surrounding a second end of the membrane structure; A second bonding material interposed between the second flange and the membrane structure; Equipped with The thermal expansion coefficient of the second flange is greater than the thermal expansion coefficient of the second bonding material, The thermal expansion coefficient of the second bonding material is greater than the thermal expansion coefficient of the membrane structure. The membrane assembly of claim 1 .

3. The first flange is made of a ceramic material. A membrane assembly according to claim 1 or 2.

4. The second flange is made of a ceramic material. The membrane assembly of claim 2.

5. The membrane structure is a reactor. A membrane assembly according to claim 1 or 2.

6. The membrane structure is a separation filter. A membrane assembly according to claim 1 or 2.

7. A membrane assembly according to claim 1; a cylindrical housing that contains the membrane assembly; A separation membrane module comprising:

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