JPH08266872A - Production of hollow fiber membrane type separation module - Google Patents

Abstract

PURPOSE: To obtain a module free from the breaking of the end part of a hollow fiber membrane and the change of the inside diameter by covering the end parts of plural hollow fiber membrane with a thermoplastic resin powder and after that, bundling the plural hollow yarn membrane to insert into a tubular casing, filling the gap part with the resin power and thermally melting the resin powder by heating and cooling the melt to solidify. CONSTITUTION: The plural hollow fiber membrane made of a polyolefin or the like is formed into the bundle, tied up with a string in the center part (a), bent into U-shape at the part of string and inserted into the casing 5 having an inlet pipe 6 (b). Next, the bundle is dipped in a vessel 4 containing a high concn. suspension 8 prepared by adding ethanol to a polyolefin resin fine powder and stirring, with spreading the projecting parts of the bundle (d). After that, the resin powder is melted by heating the end parts with a heater block 13 after evaporating ethanol to dry by heating and succeedingly cooled and solidified by setting in a centrifuge 10. Then, the tip part of the melt-sticking surface is cut and the hollow fiber membrane module having the fixed end parts 3 in one side is completed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to the electronic industry, food industry,
The present invention relates to a method for producing a hollow fiber membrane type separation module which is used in fields requiring low elution and chemical resistance such as in the pharmaceutical industry.

[0002]

2. Description of the Related Art A hollow fiber membrane separation module is a unit in which a plurality of hollow fiber-like porous membranes are bound together and the ends are fixed and incorporated into a housing to form a unit. As a means for fixing the ends, an adhesive agent made of polyurethane-based or epoxy-based resin has been conventionally used. However, with the method of fixing with an adhesive, there is elution from the adhesive, and it is also poor in heat resistance and chemical resistance.
It has a drawback that it can only be used for limited applications such as water purifiers. There is a heat fusion method as an alternative to fixing with the adhesive. In this method, a space between a plurality of hollow fiber-like porous membranes is filled with a heat-fusible resin such as a polyolefin resin and heated to be integrated. There are problems that it is difficult to maintain the shape, the hollow fiber-shaped porous membrane is crushed, or the inner diameter and outer diameter of the hollow fiber membrane are changed.

As a means for solving this problem, Japanese Patent Application Laid-Open No. 1-293105 discloses that the inside of the hollow fiber membrane where heat is melted is sealed with a substance that does not flow when heated, A method is described in which a thermoplastic resin is filled in a gap between end portions of a yarn film, heated and melted to be bonded, and then a filling agent is removed. Then, specifically, a heat-shrinkable tape is wound around the outer periphery of the bundle of hollow fiber-shaped porous membranes packed with the auxiliary member to be fixed, and this is heated so that the auxiliary member is completely hollow-fiber-like porous. It has been shown that the yarn bundle is clamped and liquid-tightly heat-sealed by filling the gap between the membranes and shrinking the heat-shrinkable tape.

Further, Japanese Patent Application Laid-Open No. 4-63117 discloses a hollow fiber membrane separation unit in which an olefin resin is used as the material of the hollow fiber membrane and the sealing agent at the binding end of the hollow fiber membrane. Then, as a method for manufacturing this hollow fiber type membrane separation unit, a suspension of fine powder of a polyolefin resin as a sealing agent is prepared, and the hollow fiber membrane is bound to this, and the binding end portion is dipped to remove the sealing agent. A method is disclosed in which the liquid of the suspension is evaporated by heating to a temperature equal to or higher than the melting point, the fine powder of the sealing agent is brought into a molten and fluidized state, and then slowly cooled and solidified to room temperature. However, in this manufacturing method, since the operation for filling the voids between the fine powders of the sealing agent is not performed at the time of heating and melting, many bubbles remain, so that the durability of the initial sealability and the heat and pressure resistance cannot be guaranteed. There was a problem of wanting.

On the other hand, the above-mentioned Japanese Patent Laid-Open No. 1-293105.
In the method described in the publication, a heat-shrinkable tape is wrapped,
As a result, the yarn bundle is tightened, and the heat-melted auxiliary member can fill the gap between the hollow fiber-shaped porous membranes and is heat-melt-bonded in a liquid-tight manner. The above-mentioned operation must be performed, and the outer diameter dimension after contraction is not constant because it is wrapped arbitrarily. The filtration element (hollow fiber membrane separation module element) produced in this way is used by inserting it into a tube-shaped casing. Between
The O-ring packing needs to be used again or the auxiliary member needs to be welded again. Therefore, in the former case, the packing material elutes, and the sealing material between the packing material comes out due to the variation in the outer diameter of the filter element and the durability problem occurs. This causes problems such as defective sealing due to remelting between the hollow fiber membranes and an increase in the number of manufacturing processes.

[0006]

Therefore, the present inventor has completed the present invention as a result of various studies in order to solve the above-mentioned problems, and an object of the present invention is to provide a plurality of polymer materials. In a hollow fiber membrane type separation module in which the hollow fiber membranes are bundled and incorporated in a tube-shaped casing at a high density, the end portions of the hollow fiber membranes are crushed, or the inner diameter of the hollow fiber membranes is measured. The present invention provides a hollow fiber membrane module liquid-tightly and integrally bonded to the hollow fiber membrane module, maintaining its shape without changing its shape.

[0007]

SUMMARY OF THE INVENTION The gist of the present invention is a hollow fiber membrane type separation in which a plurality of hollow fiber membranes made of a polymer material are bundled and incorporated in a tube-shaped casing at a high density. In the method for producing a module, the ends of a plurality of hollow fiber membranes made of a polymer material and having their ends sealed are covered with a thermoplastic resin powder, and then bundled into a tube-shaped casing. After filling the hollow fiber membrane bundle and the casing and the gap between the hollow fiber membranes with the resin powder, the resin powder is heated to melt the resin powder and the end of the hollow fiber membrane is embedded in the molten resin. After doing
A method for producing a hollow fiber membrane-type separation module, characterized in that the hollow fiber membrane-type separation module ends are liquid-tightly joined by cooling and solidifying while imparting centrifugal acceleration, or a polymer material. In a method for producing a hollow fiber membrane-type separation module in which a plurality of hollow fiber membranes composed of is bundled in a tube-shaped casing at a high density, the hollow fiber membrane-type separation module is made of a polymer material, and the end portions are After covering the ends of the stopped hollow fiber membranes with a molten resin, the bundles are bundled and inserted into a tube-shaped casing, and the gap between the hollow fiber membrane bundle and the casing and the hollow fibers After filling the gap between the membranes with the hot-melt resin, the hollow fiber membrane end is buried in the molten resin, and then the hollow fiber membrane separation module end is liquid-tightly integrated by cooling and solidifying while applying centrifugal acceleration. The method for producing a hollow fiber membrane type separation module is characterized in that the hollow fiber membrane type separation module is joined.

That is, in the present invention, the gap between the hollow fibers at the end of the hollow fiber membrane bundle and the gap between the hollow fiber membrane bundle and the casing are filled with resin powder, and then heated to heat the resin powder. Either by melting or by directly covering the gap between the hollow fibers at the end of the hollow fiber membrane bundle and the gap between the hollow fiber membrane bundle and the casing with a heat-melted resin, a heat-meltable resin is filled in the gap. After embedding, by solidifying while applying centrifugal force, so-called centrifugal cooling, it is possible to eliminate voids that occur when the molten resin cools and solidifies and shrinks, and thus the hollow fiber membrane bundle end portion and the hollow fiber membrane bundle end portion -It can be completely bonded without generating any bubbles between it and the singing, and when the hollow fiber membrane, the bonding resin and the casing are made of, for example, a polyolefin resin, it is a perfect allol polyolefin hollow fiber. Forming a membrane-type separation module Rukoto can.

The hollow fiber membrane of the present invention is not particularly limited, and may be any of the hollow fiber membranes commonly used in hollow fiber membrane type separation modules, such as polyolefin, polysulfone and polyvinylidene fluoride. (PVD
F), polytetrafluoroethylene (PTFE) and the like. The hollow fiber membranes and the heat-melting resin for joining the hollow fiber membrane and the casing may be appropriately selected depending on the material of the hollow fiber membrane to be used. For example, a hollow fiber membrane of polyolefin, polysulfone or polyvinylidene fluoride may be used. On the other hand, it is preferable to use a polyolefin resin and, for the hollow fiber membrane of polytetrafluoroethylene, perfluoroalkoxyalkane (PFE) or tetrafluoroethylene / hexafluoropropylene (FEP).

Prior to covering the ends of the hollow fiber membranes with the molten resin, it is preferable to seal the tips of the hollow fiber membranes. The filling is performed by filling the portion with a sealing material, but depending on the material and the diameter, the sealing can be performed by crushing the end portion due to cutting. Further, in order to prevent thermal deformation of the casing, it is preferable to attach a shape holding tube to the outside of the casing. Further, it is preferable that an annular projection is provided at a position in the vicinity of 10 to 40 mm from the tip of the inner surface of the casing to prevent the resin from being injected in excess of the required amount so as to squeeze the bundle of hollow fiber membranes. Further, a ring-shaped separate component may be used instead of the protrusion, or the hollow fiber membrane bundle may be squeezed by reducing the inner diameter of the casing midway. When an annular projection is provided on the inner surface of the casing, the hollow fiber membrane bundle is squeezed at this portion, so that the hollow fiber membranes are closely packed and the molten resin stops at this portion and does not enter further. Therefore, the molten resin in the portion below the annular projection is more evenly injected, and the seal is made more reliable.

As a method of burying the end portions of the hollow fiber membrane in the molten resin, the hollow fiber membranes are separated and resin powder is adhered to the end portions, which are then bundled and incorporated in a casing. Either a method of filling the resin powder between the membranes or between the hollow fiber membrane and the casing and then heating it to be in a molten state for embedding or embedding by directly adhering the molten resin to the end of the hollow fiber membrane may be employed. . As a method for adhering the resin powder to the end of the hollow fiber membrane, a method of immersing the end of the hollow fiber membrane in a suspension of the resin powder and adhering it is suitable. As a method of directly attaching the molten resin to the end portions of the hollow fiber membranes, the end portions of the hollow fiber membranes are separated and the molten resin is attached thereto, or the molten resin is incorporated into the casing, or The tip of the hollow fiber membrane is incorporated into the casing with the tip of the hollow fiber membrane extending outward from the casing end. In this state, the tip of the hollow fiber membrane is expanded so that molten resin can easily enter between the hollow fiber membranes. It is possible to embed the hollow fiber membrane bundle end portion in the resin by completely immersing the hollow fiber membrane after immersing it in the hollow fiber membrane to attach the molten resin to the hollow fiber membrane.

Subsequently, the hollow fiber membrane bundle end portion is embedded in the molten resin, and then the molten resin is solidified by so-called centrifugal cooling in which it is cooled and solidified while applying centrifugal acceleration. By solidifying the molten resin by centrifugal cooling, it is possible to eliminate voids that occur when the molten resin cools and solidifies and shrinks, and thereby, between the hollow fiber membrane bundle end portion and the hollow fiber membrane bundle end portion and the casing. It is possible to bond completely without generating any bubbles. The centrifugal acceleration is about 100 to 150G. After cooling and solidification, the tip of the hollow fiber membrane is cut to expose the open end of the hollow fiber membrane on the cut surface to obtain a hollow fiber membrane separation module. At this end, a synthetic resin of the same quality as the casing is used. The cap is welded and joined for use.

[0013]

EXAMPLE An example of the present invention will be shown with reference to the drawings. Example 1 FIG. 1 is an explanatory view illustrating an embodiment of the manufacturing method of the present invention. Approximately 400 to 600 hollow fiber membranes made of polyolefin and having an outer diameter of 1.2 mm are bundled into a bundle, the central part of which is bundled with a string (a), and the bundle is folded into a U-shape and folded in two. To the casing (or tube) 5 made of polyolefin and having an outer diameter of 70 mm and having an inlet pipe 6, the tip portion thereof is projected by 30 to 80 mm and inserted. The tip of the hollow fiber membrane is crushed in advance to prevent the high-concentration suspension from entering the hollow portion. An annular projection 2 is provided on the inner wall surface of the casing 5 at a distance of 10 to 40 mm from the tip for narrowing the hollow fiber membrane bundle, and the heat of the casing 5 is provided outside the casing 5. A shape holding tube 12 for controlling the deformation is attached (b). On the other hand, an appropriate amount of a polyolefin resin (PP, PE, EVA, etc.) fine powder as a sealing agent is put in a container 4, a dispersion liquid (ethanol) is added and stirred to prepare a high-concentration suspension 8 (c ). Next, the hollow fiber membrane bundle at the protruding portion of the bundle of hollow fiber membranes 1 is expanded and immersed in the high-concentration suspension 8 (d), and the high-concentration suspension is sufficiently applied around the hollow fibers, and then the suspension is suspended. The hollow fiber membrane bundle 1 is taken out from the suspension, and the whole hollow fiber membrane bundle 1 is pulled up by a string which binds the hollow fiber membrane bundle 1 (e) and drawn into the polyolefin casing 5 to form a unit (f). Subsequently, this unit is heated at a temperature lower than that of the polyolefin resin to evaporate the ethanol of the dispersion medium. Next, after drying this, the end portion is heated by the heater block 13 to a temperature above the melting point of the sealant,
Melt the sealant (g). Immediately thereafter (1-2 m
(within in) Set in the centrifuge 10, cool and solidify while applying a centrifugal force of 100 to 150 G (h), take out from the centrifuge 10, remove the shape-retaining tube 12, and remove the tip of the welding surface. 5 to 10 mm was cut, and the open end of the hollow fiber membrane was exposed on the cut surface to obtain an all-hollow polyolefin hollow fiber membrane module having a fixed end 3 on one side (i). A polyolefin cover body (cap) was welded to the end of the module and used (j).

Embodiment 2 FIG. 2 is an explanatory view explaining an embodiment of the manufacturing method of the present invention. The hollow fiber membrane bundle 1 (a) whose both ends are pre-sealed and the central portion is bound with a string is folded in two at the central portion,
Insert into the casing 5 from the folded side (b). In addition, on the inner wall surface of the casing 5, 10
Annular protrusion 2 to squeeze the bundle of hollow fiber membranes at ~ 40 mm
A shape holding tube 12 for controlling thermal deformation of the casing 5 is attached to the outside of the casing 5. The end of the hollow fiber membrane bundle 1 that has been stopped
About 30 to 50 mm is projected from the sing 5, and the string is fixed to the jig 9 in this state (c). At that time, between the hollow fiber membrane comrades,
The fan shape was expanded so that the resin could easily enter. Heater
Pellet or powder resin was gradually charged into the block 13 to be melted and immersed in a bath of molten resin 7 (d). The resin used was polyolefin. The charging amount was set to a distance of about 5 to 10 mm from the end of the casing so that the molten resin did not adhere to the end of the casing. After the molten resin is adhered and filled between the hollow fiber membranes,
The jig 9 was raised to pull up the hollow fiber membrane bundle 1 into the casing 5 to incorporate the hollow fiber membrane bundle into the casing, and the end portion thereof was embedded in the resin. Then, immediately (within 1 to 2 minutes), the centrifugal force is set in the centrifuge 10 (e), cooled and solidified while applying a centrifugal force of 100 to 150 G, and then taken out from the centrifuge 10 and then the shape-retaining tube 12 is removed. 5 to 10 mm from the tip of the welded surface is removed and the open end of the hollow fiber membrane is exposed on the cut surface to obtain an all-hollow polyolefin hollow fiber membrane module having a fixed short end portion 3 on one side. (F). A polyolefin-made cover body (cap) 11 is welded and joined to the end of the module and the other end of the casing, and is used (g).

As the hollow fiber membrane type separation module obtained by the production method of the present invention, one end of the hollow fiber membrane incorporated in the casing is fixed to the casing and the other end is U-shaped. The hollow fiber membrane may be folded back, or both ends of the hollow fiber membrane may be fixed to the casing. This is illustrated in FIG. 3, in which one end of the hollow fiber membrane is fixed to the casing and the other end is U-shaped.
In addition, FIG. 4 shows that both ends of the hollow fiber membrane are fixed to the casing. In the case of FIG. 3, one end of the hollow fiber membrane bundle 1 incorporated in the casing is fixed to the casing 5, and the other end is folded back in a U shape, and FIG. 4 is a hollow fiber. Both ends of the membrane bundle 1 are fixed to the casing 5. When fixing both ends of the hollow fiber membrane bundle 1, the ends are welded one by one, but in order to realize this, the casing is divided into upper and lower parts, and the upper and lower casings can be slid. When the other is welded, the casing which is not welded is slid to protrude the bundle of hollow fiber membranes and welded as described above.

In the molten resin joint portion 3 thus obtained by the method of the present invention, the gap between the hollow fiber membranes and the gap between the hollow fiber membrane bundle 1 and the casing 5 are embedded in the molten resin. After that, the hollow fiber membranes are solidified by centrifugal cooling, and the hollow fiber membrane bundle 1 and the hollow fiber membrane bundle 1 and the casing 5 are securely fixed and integrated. The casing 5 has the annular protrusion 2,
One end in FIG. 3 and both ends in FIG. 4 are closed by the cap body 11. Therefore, the fluid to be treated flows in through one fluid inflow hole 15 and flows out through the other fluid outflow hole 16. Reference numeral 14 in FIGS. 3 and 4 is an air vent port, and in the case of FIG. 4, 14 is a filtrate outlet which also serves as an air vent port.

[0017]

As described above, in the hollow fiber membrane type separation module of the present invention, a plurality of hollow fiber-like porous membranes and a casing are integrally joined by a molten thermoplastic resin. Therefore, it has a low elution property and is excellent in chemical resistance, heat resistance and sealability. Further, since the end fixing of the hollow fiber-shaped porous membrane is a heat welding method, there is no problem of the adhesive agent elution component in the conventional adhesive method, and in the production, since the centrifugal cooling solidification method is used, the production becomes extremely easy, Since voids and voids are eliminated, stable quality products can be provided at low cost.

[Brief description of drawings]

FIG. 1 is an explanatory view of a method for producing a hollow fiber membrane type separation module of Example 1 according to the present invention.

FIG. 2 is an explanatory view of a method for producing a hollow fiber membrane type separation module of Example 2 according to the present invention.

FIG. 3 is a partial sectional side view of an example of a hollow fiber membrane type separation module according to the present invention.

FIG. 4 is a partial cross-sectional side view of another example of the hollow fiber membrane type separation module according to the present invention.

[Explanation of symbols]

1 Hollow Fiber Membrane (Bundle) 2 Annular Protrusion 3
Molten resin joint 4 Container 5 Casing 6
Inlet pipe 7 Molten resin 8 Suspension 9
String fixing jig 10 Centrifuge 11 Cover 1
2 Shape-retaining tube 13 Heater block 14 Air vent port 1
5 Liquid inflow hole 16 Liquid outflow hole 24 Filtrate outlet

Claims (2)

[Claims] 1. A method for producing a hollow fiber membrane-type separation module in which a plurality of hollow fiber membranes made of a polymeric material are bundled and incorporated in a tube-shaped casing at a high density. After covering the ends of a plurality of hollow fiber membranes made of a material and having their ends sealed with a thermoplastic resin powder, they are bundled together and
After being inserted into the hollow casing, the space between the hollow fiber membrane bundle and the casing and the space between the hollow fiber membranes are filled with the resin powder, the resin powder is heated to heat-melt the resin powder to end the hollow fiber membrane. The hollow fiber membrane type separation module is characterized in that after the portion is embedded in a molten resin, the hollow fiber membrane type separation module is joined in a liquid-tight manner by cooling and solidifying while applying centrifugal acceleration. Manufacturing method. 2. A method for producing a hollow fiber membrane-type separation module in which a plurality of hollow fiber membranes made of a polymer material are bundled and incorporated in a tube-shaped casing at a high density. After covering the ends of a plurality of hollow fiber membranes made of a material and having their ends sealed with molten resin, they are bundled and inserted into a tube-shaped casing to form a hollow fiber membrane bundle and a casing. -The hollow fiber membrane type separation module is filled with the molten resin by filling the space between the singing and the hollow fiber membranes with each other and burying the end portion of the hollow fiber membrane in the molten resin, and then cooling and solidifying while applying centrifugal acceleration. A method for producing a hollow fiber membrane type separation module, characterized in that the end portions are liquid-tightly joined together.