JP4398504B2 - All fluororesin membrane module - Google Patents

Description

The present invention relates to an all-fluororesin membrane module, and in particular, is used for gas-liquid absorption, deaeration and filtration in semiconductors, foods, and other fields, and particularly preferably used as an ozone dissolution membrane module. In the container, a membrane element in which a plurality of hollow fiber-like porous separation membranes are converged is accommodated, and the liquid is introduced into the pores of the separation membrane of the membrane element from the liquid inflow hole provided in the container. Ozone in the introduced gas permeates the separation membrane to generate ozone-dissolved water, and this ozone water is led out from an outflow hole provided in the container .

  In a separation membrane module in which a membrane element in which a plurality of hollow fiber porous separation membranes of this type are bundled is contained in a container, a sealing material for the fluororesin separation membrane and a housing (container for housing the fluororesin separation membrane) In general, a resin material such as an epoxy resin or polysulfone is used.

  However, the physical properties of resin materials such as these epoxy resins are limited, so that their use as a separation membrane joule may be limited. In particular, it is difficult to use for removing and collecting solids in a chemical solution having strong oxidizing power such as concentrated nitric acid or a solvent having strong dissolving power such as acetone, or for dissolving ozone for precision cleaning of semiconductors.

  In recent years, in semiconductor manufacturing processes and liquid crystal display manufacturing processes, etc., decomposition and removal of residual organic substances such as surfactants on silicon wafers, glass substrate cleaning, cleaning after etching processing, cleaning after lapping processing, etc. Ozone-added ultrapure water is used, and needs for ozone-dissolved water are increasing. Therefore, in particular, a separation membrane module excellent in chemical resistance such as ozone resistance is desired, and various proposals have been made.

  For example, JP-A-6-296836 proposes an ozone resistant membrane module having a hollow fiber membrane made of fluororesin, a housing portion made of stainless steel or the like, and an end sealing portion made of silicone resin.

JP-A-6-296836

  However, Japanese Patent Laid-Open No. 6-296836 has a problem that the sealing performance of the gap between the housing portion made of stainless steel or the like and the end sealing portion is insufficient, and the fluid easily leaks from the housing to the outside.

  In order to improve the sealing performance between the members, it is conceivable to arrange an O-ring such as silicon rubber between the members. However, when exposed to ozone gas in long-term use, cracks occur, and in particular, ozone and wetness. Since it is partially decomposed by ozone, the sealing performance is deteriorated. Therefore, chemical resistance is also required for the O-ring, but if the O-ring is made of a fluororesin or the like like the other members of the module, it may be difficult to obtain airtightness.

In particular , if the configuration is a combination of different types of members, the connection between the members is insufficient, and fine particles and the like may enter the housing from the gaps between the members, which may affect the purity of the liquid. Therefore, low dust generation is also required. Further, it is conceivable to fill the gaps between the members by welding or the like, but depending on the place where the welding is performed, a load may be applied during use, and the sealing performance may be impaired depending on the degree of the load. Therefore, in the module as described above, it is required that no foreign matter enters or exits the housing.

The present invention has been made in view of the problems described above, low dusting properties, and a second object is to prevent the contamination of fine particles into the housing.

In order to solve the above-mentioned problems, the present invention provides a separation membrane element in which the ends of a separation membrane made of a plurality of fluororesin hollow fibers are converged and sealed with a fluororesin. In the all fluororesin membrane module housed in a fluororesin housing with caps that close both ends of the axial direction of the
The cap attached to one end of the cylindrical member is provided with a fluid inflow passage into the housing and a fluid inflow passage through which fluid flows into the hollow fiber of the separation membrane element , while the cap at the other end is inserted into the cap from the housing. A fluid outflow path for allowing fluid to flow out from the hollow fiber of the separation membrane element,
The joint portion protruding from the pipe connection side of the fluid inflow path and the fluid outflow path of the caps at both ends and integrally provided with a joint, forming a male screw on the outer peripheral surface of the joint, and projecting from the outer surface of the cap An all-fluororesin film-forming module is provided in which a pipe tip is externally fitted to and connected by screw fastening.
In the all-fluororesin-made membrane module of the present invention, a seal portion is provided between the end face of the both ends converging portion of the separation membrane element and the cap of the housing, and is continuous in the circumferential direction with one of the seal portions. And providing a concave portion continuous in the circumferential direction fitted to the convex portion on the other sealing surface, and
It is preferable that the separation membrane element and the housing are screwed together and fixed with screws, and the concave portion and the convex portion of the seal portion are press-fitted and tightly fitted by pressurization by the screw tightening. .

In this way, with the sealing part between the converging part of the separation membrane element and the cap or / and the tubular material of the housing, the concave part and the convex part that are continuous in the circumferential direction are tightly fitted in a pressurized state. Sealability is improved.
Further, in the present invention, all of the constituent members of the module such as the membrane element and the housing are made of fluororesin, and no separate O-ring or the like is used for the seal portion, and all of the contact portion with the processing fluid is fluorine. Since it is made of resin, it can realize extremely excellent chemical resistance and heat resistance.

The direction in which the concave portion and convex portion of the seal portion are provided (the concave direction and the protruding direction) may be any direction such as the axial direction or the radial direction of the tubular portion of the membrane module and the housing.
In addition, the concave and convex portions of the sealing portion are continuously provided in the circumferential direction on the surface that becomes the sealing surface of the converging portion, the cylindrical portion, and the cap. The shape may be combined as appropriate according to the shape of the members such as the converging portion, the cylindrical portion, and the cap.
Furthermore, the seal part for fitting the annular uneven part is provided in multiple or double places, or provided in different places, etc., and the uneven parts are respectively fitted in the plurality of seal parts for more sealing performance. Can also be increased.

  The concave portion and the convex portion have a shape in which the convex portion is press-fitted into the concave portion by making the sectional shape of the convex portion larger than the sectional shape of the concave portion. For example, the cross-sectional shape of the concave portion and the convex portion is a triangular shape, and the vertex angle of the concave portion and the convex triangle that are fitted to each other is larger than the vertex angle of the concave portion. 60 ° and the convex part are preferably 90 °. By making the apex angle of the convex portion larger than the apex angle of the concave portion where the concave and convex portions are fitted, the adhesion force due to the press-fitting of the convex portion and the concave portion can be further increased, and the concave and convex fitting is not released, and the seal Sexuality can also be enhanced. The cross-sectional shape of the concave portion and the convex portion can be various shapes such as a polygonal shape and a circular shape as long as the concave and convex portions can be fitted to each other.

Specifically, the concave portion or the convex portion is provided annularly on the peripheral edge portion of the axial end surface of the converging portion of the separation membrane element, while the convex portion or concave portion is provided on the peripheral edge portion of the inner surface of the lid portion of the cap. Provided in a ring, and
A screw screwed to each other in a peripheral wall inner surface of the outer peripheral surface and the cap of the focusing portion of the separation membrane element is provided, a-ring-shaped concave-convex portion during screwing fixing by screwing the separation membrane element and the cap Closely fitted under pressure.

Moreover, while providing the convex part which continues in the circumferential direction in any one sealing surface of the sealing part of the cylinder material of the said housing and a cap, it is in the circumferential direction fitted with the said convex part in the other sealing surface. Providing a continuous recess, and
Screws are provided on the peripheral wall of the cylindrical member and the cap or the peripheral wall of the cap link that fits externally on the cap, and are fixed by screw tightening. The concave portion and the convex portion of the seal portion are press-fitted by pressurization by the screw tightening. The structure is tightly fitted.
With the above configuration, in addition to the sealing performance between the converging portion of the separation membrane element and the cylindrical portion or the cap, the sealing performance between the cylindrical portion of the housing and the cap can be enhanced.

Furthermore, it is preferable that the joining surface of the converging part of the separation membrane element and the cap, the tubular material and the cap or the cap ring fitted on the cap or the cap ring is welded using PFA which is a fluororesin after being fixed with screws. .
In addition, the sealing performance can be improved by using concave and convex fitting, and when the PFA welding using PFA which is a fluororesin is used together, the sealing performance can be further improved. PFA welding is preferably performed continuously in the circumferential direction at the end of the sealing surface between the converging part and the cylinder part or cap.

The fluororesin separation membrane is composed of an assembly of a plurality of hollow fibers made of PTFE, and a plurality of the separation membranes are bundled together, and both ends in the axial direction are integrally fixed with PTFE or a heat-melting fluororesin, The separation membrane element is formed.
By constituting a plurality of separation membranes from an aggregate of hollow fibers, it is possible to perform processes such as filtration and separation more efficiently. The hollow fiber of PTFE has a fine fibrous structure in which flexible fibers are connected in a three-dimensional network, and there are a large number of pores surrounded by a fibrous skeleton. The pores surrounded by the fibrous skeleton have various shapes such as a slit shape, and the performance of the hollow fiber can be defined by the average pore diameter and the porosity of the pores.

  Examples of the fluororesin used in the fluororesin separation membrane include polytetrafluoroethylene (PTFE), tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene / hexafluoropropylene copolymer (FEP), One kind of various fluororesins such as ethylene / tetrafluoroethylene copolymer (ETFE), polychlorotrifluoroethylene (PCTFE), ethylene / chlorotrifluoroethylene copolymer (ECTFE), polyvinylidene fluoride (PVDF) or the like It can be used by a combination of plural kinds. PTFE is particularly preferable from the viewpoint of excellent molding processability and excellent mechanical strength.

As described above, the present invention is an all fluororesin film forming module,
The cap attached to one end of the cylindrical member is provided with a fluid inflow passage into the housing and a fluid inflow passage through which fluid flows into the hollow fiber of the separation membrane element , while the cap at the other end is inserted into the cap from the housing. A fluid outflow path for allowing fluid to flow out from the hollow fiber of the separation membrane element,
The joint portion protruding from the pipe connection side of the fluid inflow path and the fluid outflow path of the caps at both ends and integrally provided with a joint, forming a male screw on the outer peripheral surface of the joint, and projecting from the outer surface of the cap The pipe end is fitted externally and connected by screw tightening.

According to the above configuration, since the joint with the pipe is not joined to the cap by welding or the like, the joint portion is provided so as to protrude from the outer surface of the cap. In addition, mixing of fine particles into the housing can be prevented, and low dust generation can be achieved.
Thus, when it is set as low dust generation property, it is used suitably as a microfiltration filter etc. which mainly use semiconductor chemical | medical solution refinement | purification, and is used suitably especially for the melt | dissolution of ozone for precision cleaning.

It is preferable that the joint portion protrudes vertically from the outer surface of the cap, which is excellent in workability at the time of pipe connection, and also allows fluid to easily flow. In addition, you may provide the fluid inflow path and outflow path in the cylinder part of a housing in radial direction.
The external thread on the outer peripheral surface of the joint is provided by cutting.

The inner surface of the cap projecting on the outer surface of the joint portion is provided with a seal surface comprising the above-mentioned recess or projection, while the end surface of the separation membrane element is provided with a seal surface comprising a projection or recess, and the inner surface of the peripheral wall of the cap The male screw formed on the outer peripheral surface of the separation membrane element is screwed with the female screw formed on the outer periphery.
By setting it as the said structure, it can be set as the all fluororesin module which is excellent in sealing performance and low dust generation property.

  As is clear from the above description, according to the present invention, the separation membrane element is provided with the concave and convex portions respectively fitted to the sealing portion of the separation membrane element and the sealing portion of the cap and the sealing portion of the cap link and the cylindrical material. When the screw portions provided on the cap, the cap link, and the cylinder member are screwed together and tightened, the concave and convex fitting portion is fitted in a pressurized state to enhance the sealing performance, thereby forming a module. The sealing performance between the members can be improved. As a result, the outflow of fluid from the inside of the housing can be prevented.

In particular, in the present invention, the joint is not joined to the cap by welding or the like, but the joint portion is provided integrally with the cap and protrudes outward, and a male screw is formed on the outer peripheral surface thereof. As a result, mixing of fine particles into the housing can be prevented, and low dust generation can be achieved. It is preferably used as a microfiltration filter or the like mainly used for semiconductor chemical liquid purification, and particularly preferably used for dissolving ozone for precision cleaning.

In addition, all the components of the module consisting of separation membrane elements, cylinders, caps, and cap links are made of fluororesin, and all of the contact parts with the processing fluid are made of fluororesin. The chemical resistance and heat resistance can be realized.
Therefore, when the all-fluororesin film-forming module of the present invention is used for ozone dissolution, in the semiconductor manufacturing process, the liquid crystal display manufacturing process, etc., decomposition and removal of residual organic substances such as surfactants on the silicon wafer, cleaning of the glass substrate Further, it is possible to obtain ozone-added ultrapure water used for cleaning after the etching process, cleaning after the lapping process, and the like.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1 to 3 show an all-fluorine resin film forming module 10 for dissolving ozone according to a first embodiment of the present invention.
The all fluororesin membrane module 10 includes a plurality of fluororesin separation membranes 11 that are long in the vertical direction in the drawing and arranged substantially parallel to each other at intervals, and converges the upper and lower end portions 11a at both ends in the axial direction. Made of PTFE, which is provided with a separation membrane element 12 integrated with a sealing material made of PTFE, a cylindrical tube member 13 and a cap 14 (14A, 14B) with hooks for closing both end openings 13a of the tube member 13. A pressure-resistant housing 15 is provided.

  The plurality of fluororesin separation membranes 11 whose both ends are converged are each made of an aggregate of PTFE hollow fibers. As shown in FIG. 2, a large number of fluororesin separation membranes 11 are bundled with a gap, and the gap material is filled with a sealing material 160 made of PTFE at both ends in the axial direction to be integrated and focused. The front end opening of the hollow fiber is exposed on the end surface 16a of the converging part 16, and fluid can flow from one end opening of each hollow fiber to the other end opening.

As shown in FIGS. 1 and 3, the upper and lower caps 14 have a peripheral wall 14b protruding from the outer periphery of the closing portion 14a, and both end converging portions 16 of the separation membrane element 12 are disposed in an internal space surrounded by the closing portion 14a and the peripheral wall 14b. The shape is fitted.
A recess 21 for sealing with the separation membrane element 12 is provided annularly on the peripheral portion of the inner surface 14a-1 of the closing portion 14a of the cap 14, and a female screw for attaching the separation membrane element to the inner peripheral surface of the peripheral wall 14b. 50 is provided.
Moreover, the convex part 23 for sealing with the said cylindrical material 13 is provided in cyclic | annular form in the lower end inner surface of the surrounding wall 14b.

  A cap ring 17 is externally fitted to the cap 14, and a female screw 60 is provided on the inner peripheral surface of the cap ring 17, and screwed with a male screw 61 formed on the outer peripheral surface of the upper and lower end portions of the tubular material 13. Thus, the upper and lower openings 13a of the cylindrical member 13 are closed by the closing portion 14a of the upper and lower caps 14.

  On the peripheral edge of the distal end surface 16a of the both-end converging portion 16 of the separation membrane element 12, a sealing convex portion 20 is provided in an annular shape so as to be fitted with the sealing concave portion 21 of the cap 14 and connected to the outer peripheral surface. The male screw 51 is formed and screwed into the female screw 50 of the cap 14.

As shown in FIG. 4, the cross-sectional shapes of the concave portion 21 and the convex portion 20 are each triangular, and the apex angle of the triangular shape of the concave portion 21 and the convex portion 20 that are fitted to each other is higher than the apex angle of the concave portion 21. The vertex angle of is increased. Specifically, the vertex angle of the concave portion 21 is 60 °, and the vertex angle of the convex portion 20 is 90 °.
Therefore, when the convex portion 20 of the converging portion 16 and the concave portion 21 of the cap 14 are fitted in the concave and convex portions, the male screw 51 of the converging portion 16 is screwed into the female screw 50 of the cap 14 and tightened. The separation membrane element 12 and the upper and lower caps 14 are connected in a state where the portion 20 is forcibly press-fitted into the concave portion 21 and the convex portion 20 is in close contact with the concave portion 21 with a strong force.
In addition, as shown to FIG. 4 (A) (B), recessed part 21 'and convex part 20' are good also as a cross-sectional trapezoid shape or circular arc shape.

At the upper and lower ends of the cylindrical member 13, a small-diameter cylindrical portion 13 c that fits around the peripheral wall 14 b of the cap 14 protrudes, a concave portion 24 for sealing is provided at the front end surface, and a male screw 61 is formed on the outer peripheral surface. Yes.
The concave portion 24 of the cylindrical member 13 is concavo-convexly fitted with the convex portion 23 of the cap 14, and the cross-sectional shape of the concavo-convex portions 24 and 23 is similar to the concave and convex portions 21 and 20 shown in FIG. Therefore, when the female screw 60 of the cap link 17 is screwed into the male screw 61 of the cylindrical member 13 and tightened, the convex portion 24 is forcibly pressed into the concave portion 23, and the convex portion 23 adheres to the concave portion 24 with a strong force. In this state, the tubular member 13 and the cap 14 are connected.

  Further, after the converging part 16 and the cap 14 of the separation membrane element 12 to be connected by screw tightening as described above and the cap link 17 and the cylinder member 13 fitted to the cap 14 are screwed and fixed, the peripheral wall 14b of the cap 14 is fixed. In the boundary surface between the lower end and the outer peripheral surface of the converging portion 16, the lower end of the cap link 17 and the outer peripheral surface of the tubular member 13, and the boundary between the cap 14 and the cap link 17, the entire periphery of the portion indicated by the black circle P in the figure Are PFA welded.

Furthermore, an inflow path 31 through which ozone gas flows into the housing 15 and an inflow path 32 through which pure water flows into the hollow fibers of the separation membrane element 12 are provided in the closing portion 14a of the lower cap 14B. An outflow path 33 for discharging exhaust ozone gas into the housing 15 and an outflow path 34 for discharging ozone-dissolved pure water from the hollow fiber of the separation membrane element 12 are provided in the closed portion 14a of the upper cap 14A.
On the piping connection side of the inflow path and the outflow path of the caps 14A and 14B, joint portions 35 to 38 that are cylindrical from the outer surface of the closing portion 14a are integrally provided.
Male threads 35a to 38a are engraved on the outer peripheral surfaces of these joint portions 35 to 38, and pipes (not shown) are externally fitted to the joint portions 35 to 38 projecting from the cap 14 when the pipes are connected, and are connected by screw tightening. is doing.

  In assembling the all-fluororesin membrane module 10 having the above-described configuration, the upper and lower caps 14 are connected to both ends of the separation membrane element 12 by screwing, and the sealing uneven portions 21 and 20 are fitted in a pressurized state. Next, in a state where the separation membrane element 12 is passed through the cylindrical member 13, the lower cap link 17 is externally fitted to the lower cap 14 </ b> A, and is connected to the lower cap link and the lower end of the cylindrical member 13 by screwing. Next, the upper cap link 17 is externally fitted to the upper cap 14B, and the upper cap link 17 is connected to the upper end of the tubular member 13 by screwing.

  In the all-fluororesin membrane module 10 assembled in this manner, the sealing portion of the separation membrane element 12 and the sealing portion of the cap 14 and the sealing portion of the cap link 17 and the cylindrical member 13 are both annular sealing protrusions. Since the portion is in close contact with the sealing recess by screw tightening, the sealing performance can be very high. As a result, fluid leakage from the inside of the housing 15 to the outside can be prevented.

  In addition, the joint with the pipe is not protruded by welding to the cap 14, but the joint portions 35 to 38 are provided so as to protrude integrally from the outer surface of the cap 14, and the joint portions 35 to 38 are connected to the pipe. By connecting, foreign matter such as fine particles generated during screw tightening rotation is reliably prevented from entering the housing. Thus, since it can be made low dust generation property, it is particularly suitably used for dissolving ozone for precision cleaning.

  Furthermore, since all of the components of the module such as the membrane element 12 and the housing 15 are made of fluororesin and all of the contact parts with the processing fluid are made of fluororesin, extremely excellent chemical resistance and heat resistance are achieved. Can be realized.

The present invention is not limited to the above embodiment, and the concave portion and the convex portion may be interchanged in the seal portion between the converging portion and the cap and the seal portion between the cap link and the cylindrical member.
Moreover, you may provide a cap and a cap link integrally.
Further, the converging part of the membrane element may be sealed using a heat-meltable fluororesin.
As the fluororesin separation membrane, various fluororesins can be used in addition to PTFE. Further, a heat-meltable fluororesin may be used for the housing.
Further, the terminal converging part of the separation membrane element is fitted into both ends of the cylindrical material, and a cap is fitted to the cylindrical material to be attached, and the sealing uneven fitting is provided between the separation membrane element and the cylindrical material. It is good also as a structure which provides a joint part.
Furthermore, although the membrane module of the above embodiment is for ozone dissolution, it can be suitably used for gas-liquid absorption, deaeration, filtration, etc. in semiconductors, foods, and other fields.

It is sectional drawing of the all fluororesin module of 1st Embodiment. It is drawing which shows the end surface of the condensing part of a separation membrane element. (A) is the principal part enlarged view of FIG. 1, (B) is an exploded view. It is drawing which shows the recessed part and convex part for a seal | sticker. (A) (B) is drawing which shows other embodiment of uneven | corrugated fitting.

Explanation of symbols

10 Fluororesin Membrane Module 11 Fluororesin Separation Membrane 12 Separation Membrane Element 13 Tubular Material 14 Cap 15 Housing 16 Converging Portions 20, 23 Convex Portions 21, 24 Concavities 35-38 Joint Portions 35a-38a Male Screws

Claims (2)

A separation membrane element in which the ends of a separation membrane made of a plurality of fluororesin hollow fibers are converged and sealed with a fluororesin is integrated with a cylinder and a cap that closes both ends of the cylinder in the axial direction. In an all fluororesin film module housed in a fluororesin housing,
The cap attached to one end of the tubular member is provided with a fluid inflow passage into the housing and a fluid inflow passage through which fluid flows into the hollow fiber of the separation membrane element , while the cap at the other end is inserted into the cap from the housing. A fluid outflow path for allowing fluid to flow out from the hollow fiber of the separation membrane element,
The joint portion protruding from the pipe connection side of the fluid inflow path and the fluid outflow path of the caps at both ends and integrally provided with a joint, forming a male screw on the outer peripheral surface of the joint, and projecting from the outer surface of the cap An all-fluororesin film-forming module characterized in that a pipe tip is externally fitted to and connected by screw tightening.   The all-fluororesin film-forming module according to claim 1, wherein the module is an ozone-dissolving module for precision cleaning.

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