JP2023063385A - Separation membrane module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a separation membrane module which prevents rapid application of a high pressure on a secondary side when defect is generated on a membrane, a support body or a seal part of it.

SOLUTION: A separation membrane module 1 includes a cylindrical housing 2, and a tubular separation membrane 3 which is arranged in a longitudinal direction of the housing 2. A treated fluid is supplied from piping 40 to a most upstream side separation membrane module 1, an impermeable fluid is supplied through piping 41 to an inflow port 9 of a downstream side separation membrane module 1, and the impermeable fluid in a most downstream separation membrane module 1 flows out through piping 42. A permeable fluid permeating the tubular separation membrane 3 in each of the separation membrane modules 1 is taken out through piping 30 and collective piping 33. An emergency operation valve 31, which is closed or opened small when a flow rate or pressure of a permeable fluid passage 30 becomes a predetermined value or more, is arranged on each of the piping 30.

SELECTED DRAWING: Figure 5

COPYRIGHT: (C)2023,JPO&INPIT

Description

TECHNICAL FIELD The present invention relates to a separation membrane module used for separating some components from fluids such as solutions and mixed gases.

A separation membrane module is known as a device for separating components in a solution or mixed gas. The tubular separation membrane used in this separation membrane module has a tubular porous ceramic support and a porous separation membrane made of zeolite or the like provided on the outer peripheral surface of the support. In order to separate a specific component from a fluid such as a solution or a mixed gas, the solution fluid is brought into contact with one side (outer surface) of the separation membrane element, and the other side (inner surface) is decompressed to remove the specific component. A method of vaporizing and separating, a method of vaporizing the solution and bringing it into contact with the separation membrane in a gaseous state, depressurizing the non-contact side to separate the specific component, and a method of contacting the pressurized mixed gas with the separation membrane. A method for separating a specific component is known (Patent Documents 1 to 3).

In Patent Document 3, by providing a filter for filtering the permeated fluid flowing out from the separation membrane module, even if the separation membrane is broken in the separation membrane module, the debris will not reach the separation membrane module installed downstream. It is described to prevent inflow.

JP 2013-39546 A JP 2011-152507 A JP 2016-155098 A

In a separation membrane module in which a separation membrane is installed in a housing, if the membrane or its support is cracked or broken, or if the sealing part is mechanically or chemically deteriorated (hereinafter referred to as a defect), it will be a primary The fluid to be treated abruptly flows out from the side (to-be-treated fluid side) to the secondary side (permeate fluid side), and a high pressure is suddenly applied to facilities such as piping and equipment connected to the secondary side.

SUMMARY OF THE INVENTION An object of the present invention is to provide a separation membrane module that prevents sudden application of a high pressure to the secondary side when a defect occurs in the membrane, its support, or the seal.

The separation membrane module of the present invention has a housing and a tubular separation membrane arranged in the housing, a fluid to be treated is supplied into the housing, and the fluid that has passed through the tubular separation membrane is taken out. 2, characterized by comprising an emergency operation valve that closes or the degree of opening decreases when the pressure or flow rate of the permeated fluid flowing out from the separation membrane module to the permeated fluid channel reaches or exceeds a predetermined value. It is something to do.

In one aspect of the present invention, the emergency valve is a shut-off valve that shuts off the permeate fluid channel when the pressure of the permeate fluid flowing out of the separation membrane module reaches or exceeds the predetermined value.

In one aspect of the invention, the emergency actuation valve is a constant pressure or constant flow valve.

In one aspect of the present invention, a plurality of separation membrane modules are connected in series, and the permeate fluid channel of each separation membrane module is provided with the emergency valve.

The separation membrane module of the present invention is provided with an emergency operation valve that reduces the flow rate or pressure of the permeating fluid channel when the flow rate or pressure of the channel exceeds a predetermined value. Even if a defect occurs in the membrane, its support, or the sealing portion, sudden application of high pressure to the equipment on the secondary side of the separation membrane module can be prevented.

FIG. 2 is a cross-sectional view of the separation membrane module according to the embodiment along the direction of the housing axis. FIG. 2 is a sectional view taken along line II-II of FIG. 1; 2 is a cross-sectional view taken along line III-III of FIG. 1; FIG. 4 is an enlarged cross-sectional view of an end tube and a support plate; FIG. It is a flow diagram of a membrane separation system. It is a flow diagram of a membrane separation system. It is a flow diagram of a membrane separation system.

A separation membrane module according to an embodiment of the present invention will be described with reference to FIGS.

This separation membrane module 1 comprises a cylindrical housing 2 whose vertical direction is the axial direction of the cylinder, a plurality of tubular separation membranes 3 arranged parallel to the axial center line of the housing 2 , and a a bottom cover 6A attached to the lower end of the housing 2, a top cover 6B attached to the upper end of the housing 2; It has a baffle (rectifying plate) 7, a second baffle (rectifying plate) 8, and the like. The first baffle 7 is arranged above the support plate 5 .

In this embodiment, outward flanges 2a, 2b, 6b, and 6c are provided on the lower and upper ends of the housing 2 and the outer peripheral edges of the bottom cover 6A and top cover 6B, respectively, and these are fixed by bolts (not shown). It is A peripheral edge portion of the support plate 5 is supported by a support seat 2 t provided around the inner peripheral surface of the housing 2 . A sealing member is interposed between the outer periphery of the lower surface of the support plate 5 and the upper surface of the support seat 2t.

In this embodiment, an end tube 4 is connected to the lower end of tubular separation membrane 3 and an end plug 20 is connected to the upper end of tubular separation membrane 3 . Although only seven tubular separation membranes are shown in FIGS. 2 and 3, the number of tubular separation membranes can be set appropriately as described later. Also, two or more tubular separation membranes 3 may be connected by a joint pipe (not shown) to form a tubular separation membrane connection body.

An inflow port 9 for the fluid to be treated is provided on the outer peripheral surface of the lower portion of the housing 2, and an outflow port 10 for the non-permeating fluid is provided on the outer peripheral surface of the upper portion. The inlet 9 is provided to face the chamber 11 between the support plate 5 and the first baffle 7 . Outlet 10 is provided to face chamber 12 above second baffle 8 . Between the baffles 7 and 8 is a main chamber 13 for membrane separation.

A plurality of rods 14 are erected from the support plate 5 at the bottom, and the baffles 7 and 8 are supported by the rods 14 . A male screw is formed on the lower end of the rod 14 and screwed into a female screw hole of the support plate 5 . The baffles 7 and 8 are supported at a predetermined height by sheath tubes 14A and 14B (FIG. 4) fitted on the rod 14. As shown in FIG. The sleeve tube 14A is arranged between the support plate 5 and the baffle 7. As shown in FIG. The sleeve tube 14B is arranged between the baffles 7,8. The baffle 8 is mounted on the upper end surface of the sleeve tube 14B and fixed by a nut screwed onto the upper end of the rod 14. As shown in FIG. The number of baffles is not limited to this embodiment, and three or more baffles may be used.

Sealing members such as O-rings, V-packings, and C-rings may be interposed between the outer peripheral surfaces of the baffles 7 and 8 and the inner peripheral surface of the housing 2 .

Each baffle 7, 8 is provided with a circular insertion hole 7a, 8a through which the tubular separation membrane 3 is inserted. , 8a. The bore diameters of the through holes 7a and 8a are larger than the diameters (outer diameters) of the tubular separation membrane 3, the end tube 4 and the end plug 20, and the inner peripheral surfaces of the through holes 7a and 8a and the end tube 4 and the end plug 20 are aligned. A gap is formed over the entire circumference between the outer peripheral surface.

An insertion hole 5 a into which the lower end of the end tube 4 connected to the tubular separation membrane 3 is inserted is provided on the upper surface side of the support plate 5 . The insertion hole 5a is cylindrical and extends from the upper surface of the support plate 5 halfway in the thickness direction. The bottom of the insertion hole 5a faces the outflow chamber 16 below the support plate 5 through the small hole 5b and the large hole 5c.

A pipe hole 4a of each end pipe 4 communicates with an outflow chamber 16 between the bottom cover 6A and the support plate 5 via a small hole 5b and a large hole 5c. The bottom cover 6A is provided with an outlet 6a for the separated permeated fluid.

Although not shown, the end pipe 4 has a groove formed on its outer peripheral surface in the vicinity of the lower end thereof, and an O-ring made of fluororubber, fluororesin, or the like is attached. A groove concentric with the pipe hole 4a of the end pipe 4 is also provided on the lower end surface of the end pipe 4, and an O-ring is attached. Sealing between the outer surface of the end pipe 4 and the insertion hole 5a is performed by the tight contact of these O-rings with the inner peripheral surface of the insertion hole and the bottom surface of the insertion hole 5a. Only one of the O-ring on the outer peripheral surface of the end pipe 4 and the O-ring on the lower end surface may be provided.

As shown in FIG. 4, the end tube 4 has a small diameter portion 4g at its upper end and is inserted into the lower portion of the tubular separation membrane 3. As shown in FIG. An O-ring is mounted in a groove provided around the outer peripheral surface of the small diameter portion 4g. An O-ring is also interposed between the lower end surface of the tubular separation membrane 3 and the stepped surface of the end tube 4 . The connecting portion between the end tube 4 and the tubular separation membrane 3 may be sealed by using a heat-shrinkable tube without using the O-ring as described above, or by using an O-ring and further using a heat-shrinkable tube. may be used.

An end plug 20 is connected to the upper end of the tubular separation membrane 3 . The end plug 20 has a cylindrical shape or a shape obtained by shaving a part of the column, and seals the upper end of the tubular separation membrane 3 . The lower end of the end plug 20 is provided with a small diameter portion that is inserted into the tubular separation membrane 3 . An O-ring seals between the end plug 20 and the tubular separation membrane 3 . The end plug 20 and the tubular separation membrane 3 may be sealed by using a heat-shrinkable tube without using an O-ring, or may be sealed by using a heat-shrinkable tube in addition to using an O-ring.

In order to reduce the weight of the end plug 20, a recess 20v is formed from the upper end surface of the end plug 20. As shown in FIG. A drain hole communicating between the bottom of the recess 20v and the side peripheral surface of the end plug 20 may be provided.

In this embodiment, since the end plug 20 is arranged on the upper end side of the tubular separation membrane 3, the load is applied in the direction in which the end faces of the tubular separation membrane 3, the end plug 20, and the end tube 4 are pressed against each other. is hanging.

However, in the present invention, the end tube 4 and the support plate 5 may be arranged on the upper end side of the tubular separation membrane 3 and the end plug 20 may be arranged on the lower end side of the tubular separation membrane 3 . In this case, by providing an urging member such as a spring for urging the end plug 20 upward, the tubular separation membrane 3, the end plug 20, and the end tube 4 are pressed against each other at their end surfaces. Loading is preferred.

In this separation membrane module 1, the fluid to be treated is introduced from the inlet 9 into the chamber 11 of the housing 2, passes through the gap between the inner peripheral surface of the insertion hole 7a of the baffle 7 and the outer peripheral surface of the end tube 4. After flowing into the main chamber 13 and passing through the main chamber 13 , it flows out into the chamber 12 through the gap between the insertion hole 8 a of the baffle 8 and the end plug 20 . While flowing through the main chamber 13, some components of the fluid to be treated permeate the tubular separation membrane 3 and are taken out of the tubular separation membrane 3 through the outflow chamber 16 and the outlet 6a. The fluid that has not permeated flows out of the separation membrane module 1 from the outlet 10 .

The flow in the main chamber 13 and the flow in the tubular separation membrane 3 may be cocurrent or countercurrent, and the inflow port 9 and the outflow port 10 of the fluid to be treated may be interchanged.

The separation membrane module 1 may be used with the top cover 6B facing upward as shown in FIG. 1, or may be used with the bottom cover 6A facing upward. Also, the separation membrane module 1 may be placed horizontally so that the direction connecting the bottom cover 6A and the top cover 6B is substantially horizontal.

In this embodiment, a large number of tubular separation membranes 3 are arranged in parallel, and since the membrane area is large, membrane separation can be carried out efficiently.

In this embodiment, end tubes 4 and end plugs 20 connected to both upper and lower ends of tubular separation membrane 3 are inserted into insertion holes 7a and 8a of baffles 7 and 8, respectively. Therefore, even if the tubular separation membrane 3 vibrates or oscillates and the end tube 4 and the end plug 20 come into contact with the inner peripheral surfaces of the insertion holes 7a and 8a, the zeolite membrane is not damaged, and stable operation can be performed for a long period of time. It can be performed.

In this separation membrane module 1, if one or more tubular separation membranes 3 are damaged, the flow of the fluid to be treated into the housing 2 is stopped, and then the bottom cover 6A is removed from the housing 2. FIG. It is preferable to attach a closing member to the large hole 5c connected to the insertion hole 5a into which the tubular separation membrane 3 is inserted.

In this embodiment, an emergency operation valve 31 is provided in a pipe (permeated fluid flow path) 30 connected to the permeated fluid outlet 6 a of the separation membrane module 1 . This emergency operation valve closes or reduces the valve opening when the pressure or flow rate of the permeating fluid flowing through the pipe exceeds a predetermined value.

The emergency operation valve 31 may be one that closes when the pressure detected by the pressure sensor reaches a predetermined value or higher, and is a constant flow valve or constant pressure valve that sets the flow rate or pressure to a predetermined flow rate or pressure or less. and so on.

An example of a configuration in which the separation membrane modules 1 are connected in series is shown in FIG.

In FIG. 5 , an emergency operation valve 31 is provided in the permeate fluid extraction pipe 30 of each separation membrane module 1 .

The outflow side of the emergency valve 31 of the first-stage separation membrane module 1 and the emergency valve 31 of the second-stage separation membrane module 2 are connected to a collecting pipe 33 for the permeated fluid.

The fluid to be treated is supplied from the piping 40 to the separation membrane module 1 on the most upstream side, the non-permeating fluid is sequentially supplied to the inlet 9 of the separation membrane module 1 on the downstream side through the piping 41, and is supplied to the most downstream separation membrane module 1. A non-permeating fluid in the separation membrane module 1 flows out through the pipe 42 . The permeated fluid that permeates the tubular separation membranes 3 in each separation membrane module 1 is taken out through the pipe 30 and the collecting pipe 33 .

In any one or more of the separation membrane modules 1, when a defect occurs in the membrane, its support, or the sealing portion, the emergency operation valve 31 provided in the separation membrane module 1 is closed or opened. As a result, damage to equipment downstream of the permeate fluid pipe 30 can be prevented.

In FIG. 5, each separation membrane module 1 is provided with an emergency valve 31, but as shown in FIG.

As described above, the emergency valve 31 may be controlled based on the pressure detected by the pressure sensor. FIG. 7 shows an example of this, in which a cutoff valve 50 that closes when the pressure detected by the pressure sensor 51 exceeds a predetermined pressure is installed as an emergency operation valve.

In FIG. 7, the pressure sensor 51 is provided upstream of the cutoff valve 50 . By arranging in this way, there are advantages such as early detection of abnormal pressure and separation of working pressure in the cutoff valve 50 , but the pressure sensor 51 may be provided on the upstream side of the cutoff valve 50 .

In addition, an alarm device may be further installed that issues an alarm when the pressure detected by the pressure sensor 51 exceeds a predetermined value.

In the present invention, the emergency valve may be a constant flow valve or constant pressure valve as described above. In this case, a manual cutoff valve may be provided on either the upstream side or the downstream side of the constant flow valve or the constant pressure valve. The permeate flow is shut off by an operator closing the isolation valve while the flow or pressure of the permeate is controlled by the constant flow valve or constant pressure valve. This arrangement is low cost as the constant flow or pressure valve and the manual shut off valve are inexpensive.

In FIGS. 5 to 7, only one series connection of the separation membrane modules 1 is installed, but a plurality of such series connections may be installed in parallel.

Preferred materials for each member constituting the separation membrane module of the present invention are described below.

Examples of materials for the end pipe 4 and the end plug 20 include, but are not limited to, materials impermeable to fluid, such as metals, ceramics, and resins. The materials of the baffles 7 and 8 and the joint pipes are usually metal materials such as stainless steel, but are not particularly limited as long as they have heat resistance under separation conditions and resistance to feed and permeating components. material can be changed.

The tubular separation membrane 3 preferably has a tubular porous support and a zeolite membrane as an inorganic separation membrane formed on the outer peripheral surface of the porous support. Materials for this tubular porous support include inorganic porous ceramic sintered bodies and metal sintered bodies containing silica, α-alumina, γ-alumina, mullite, zirconia, titania, yttria, silicon nitride, silicon carbide, and the like. and quality supports. Among them, an inorganic porous support containing at least one of alumina, silica and mullite is preferable. The average pore diameter of the surface of the porous support is not particularly limited, but the pore diameter is preferably controlled, usually 0.02 μm or more, preferably 0.05 μm or more, more preferably 0.1 μm. Thus, it is usually 20 μm or less, preferably 10 μm or less, more preferably 5 μm or less.

The zeolite is crystallized on the surface of the porous support to form a zeolite membrane.
The main zeolite that constitutes the zeolite membrane usually contains a zeolite having a 6-10 membered oxygen ring structure, preferably a zeolite having a 6-8 membered oxygen ring structure.

The value of n of the zeolite having an oxygen n-membered ring here indicates the one having the largest number of oxygen among the pores composed of oxygen and T element forming the zeolite skeleton. For example, when pores of 12-membered oxygen rings and 8-membered rings exist like MOR type zeolite, it is regarded as zeolite of 12-membered oxygen rings.

Examples of zeolites having an oxygen 6-10 membered ring structure include AEI, AEL, AFG, ANA, BRE, CAS, CDO, CHA, DAC, DDR, DOH, EAB, EPI, ESV, EUO, FAR, FRA, FER, GIS, GIU, GOO, HEU, IMF, ITE, ITH, KFI, LEV, LIO, LOS, LTN, MAR, MEP, MER, MEL, MFI, MFS, MON, MSO, MTF, MTN, MTT, MWW, NAT, NES, NON, PAU, PHI, RHO, RRO, RTE, RTH, RUT, SGT, SOD, STF, STI, STT, TER, TOL, TON, TSC, TUN, UFI, VNI, VSV, WEI, YUG, etc. There is

The zeolite membrane may be a membrane made of zeolite alone, or a membrane formed by dispersing the zeolite powder in a binder such as a polymer, or a membrane formed by fixing zeolite on various supports. A zeolite membrane composite may also be used. The zeolite membrane may partially contain an amorphous component or the like.

Although the thickness of the zeolite membrane is not particularly limited, it is usually 0.1 μm or more, preferably 0.6 μm or more, and more preferably 1.0 μm or more. Also, it is usually 100 μm or less, preferably 60 μm or less, more preferably 20 μm or less, more preferably 12 μm or less, and particularly preferably 10 μm or less.

However, the present invention may use a tubular separation membrane having a separation membrane other than the zeolite membrane.

The outer diameter of the tubular separation membrane 3 is preferably 3 mm or more, more preferably 6 mm or more, still more preferably 10 mm or more, preferably 20 mm or less, more preferably 18 mm or less, still more preferably 16 mm or less, and particularly preferably 14 mm or less. . If the outer diameter is too small, the strength of the tubular separation membrane may be insufficient and it may become fragile, and if it is too large, the membrane area per module will decrease.

The length of the portion of the tubular separation membrane 3 covered with the zeolite membrane is preferably 20 cm or more and preferably 200 cm or less.

In the separation membrane module of the present invention, the tubular separation membranes may be of a single-tube type or a multi-tube type, and usually 1 to 5000, particularly 6 to 4000, are arranged, and the shortest distance between the tubular separation membranes is 2 mm to 10 mm. It is preferably arranged so that The size of the housing and the number of tubular separation membranes are appropriately changed according to the amount of fluid to be treated.

In the separation membrane module of the present invention, the fluid to be treated to be separated or concentrated is not particularly limited as long as it is a gaseous or liquid mixture composed of a plurality of components that can be separated or concentrated by the separation membrane. may be used, but it is preferred to use mixtures of gases.

Separation or concentration methods called pervaporation method (pervaporation method) or vapor permeation method (vapor permeation method) can be used for liquid separation or concentration. Since the pervaporation method is a separation or concentration method in which a liquid mixture is directly introduced into a separation membrane, the process including separation or concentration can be simplified.

In the present invention, when the mixture to be separated or concentrated is a mixture of gases consisting of a plurality of components, the mixture of gases includes, for example, carbon dioxide, oxygen, nitrogen, hydrogen, methane, ethane, ethylene, propane , propylene, normal butane, isobutane, 1-butene, 2-butene, isobutene, aromatic compounds such as toluene, sulfur hexafluoride, helium, carbon monoxide, nitrogen monoxide, water, etc. The one containing a component is mentioned. Among the mixture of these gas components, gas components with high permeance permeate the separation membrane and are separated, and gas components with low permeance are concentrated on the feed gas side.

1 Separation Membrane Module 2 Housing 3 Tubular Separation Membrane 4 End Tube 5 Support Plate 6A Bottom Cover 6B Top Cover 6a Outlet 7, 8 Baffle 7a, 8a Insertion Hole 9 Inlet 10 Outlet 11, 12 Chamber 13 Main Chamber 14 Rod 16 Outflow chamber 20 End plug 30 Piping (flow rate of permeated fluid)
31 emergency operation valve 33 collecting pipe 50 cutoff valve 51 pressure sensor

Claims (5)

a housing;
a tubular separation membrane disposed within the housing;
In a separation membrane module in which a fluid to be treated is supplied into the housing and the fluid that has passed through the tubular separation membrane is taken out,
Separation characterized by comprising an emergency operation valve that closes or decreases in opening when the pressure or flow rate of the permeated fluid flowing out from the separation membrane module to the permeated fluid channel exceeds a predetermined value. membrane module. 2. The method according to claim 1, wherein the emergency operation valve is a shutoff valve that shuts off the permeate fluid flow path when the pressure of the permeate fluid flowing out of the separation membrane module reaches or exceeds the predetermined value. Separation membrane module. 2. The separation membrane module according to claim 1, wherein said emergency valve is a constant pressure valve or a constant flow valve. 4. The method according to any one of claims 1 to 3, wherein a plurality of separation membrane modules are connected in series, and the permeate fluid flow path of each separation membrane module is provided with the emergency valve. separation membrane module. 4. The method according to any one of claims 1 to 3, wherein a plurality of separation membrane modules are connected in series, and a combined permeate fluid channel is provided in which the permeate fluid channels of the permeate fluid channels of the separation membrane modules join together. and
A separation membrane module, wherein the emergency valve is provided only in the collective permeate fluid channel.

Images