JPS61157307A - Hollow yarn membrane module - Google Patents

Abstract

PURPOSE:To enhance the release strength of a case and an adhesive sealed part, by arranging the adhesive of the ashesive sealed part in the order of a flexible adhesive, a non-flexible adhesive and a flexible adhesive in a laminar form in the longitudinal direction of a module. CONSTITUTION:The adhesive of the adhesive sealed part at the end part of a hollow yarn membrane module wherein hollow yarn membranes 1-1 are al lowed to fill a case 5-5 is set to such a laminar structure that a non-flexible adhesive 4-4 such as an epoxy adhesive is held between flexible adhesives 2-2, 3-3, each comprising adhesive having an urethane bond, arranged to the inside end part of the module. By this structure, the beginning of release at the contact point of the case and the adhesive sealed exposed part is suppressed by the flexible adhesives 2-2, 3-3 extremely strong to release force and, even if release is generated, the flexible adhesives 2-2, 3-3 act as packing to prevent leakage.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a hollow fiber membrane module. More specifically, the adhesive-sealed portion is arranged in layers in the length direction of the module using a flexible adhesive and a non-flexible adhesive, and the hollow portion has a structure that improves the peeling resistance of the adhesive-sealed portion. This invention relates to a thread-type membrane module.

The semipermeable membrane module, which is the heart of reverse osmosis and ultrafiltration equipment, is of various types depending on the application, and one of them, the hollow fiber membrane module, is compact. It is widely used in various fields because of its advantages such as high performance and small priming volume.

This hollow fiber type membrane module is made by bundling several thousand to tens of thousands of hollow fibers with a length of 300 to 1,000 mm and an outer diameter of 0°1 to 1 mjl and inserting them into a cylindrical case, with the ends being mainly impermeable. After adhesively sealing with a flexible epoxy adhesive and curing, cutting is performed to open the end face and for trimming, and a cap is attached by gluing, welding, or screwing.

(Prior Art) Conventionally, epoxy adhesives have been used alone to adhesively seal the ends of hollow fiber membrane modules.

(Problems to be Solved by the Invention) However, since this epoxy adhesive generates a large amount of self-heating during curing, when used in large quantities, temperature distribution occurs, resulting in uneven curing. As a result, strain will accumulate within the cured adhesive.

In addition, epoxy adhesives are inflexible and have a relatively high shrinkage rate, so a large amount of adhesive is used, especially in large-diameter hollow fiber membrane modules, which inevitably causes internal distortion. There were problems such as the case becoming hard and the adhesive peeling off from the case.

To solve this problem, for example, after curing a non-flexible epoxy adhesive, the parts that are likely to peel off due to mechanical or thermal shock are intentionally peeled off, and then the peeling is done. Hollow fiber membrane modules have been proposed in which the same non-flexible Epoquine resin is injected into the gaps and bonded together, but these are not perfect. In addition, when adhesively sealing the hollow fiber membrane module, 1~
A material that cannot be bonded with epoxy adhesive, such as a rectangular silicone rubber plate with a thickness of 5 degrees. - Rolled into an annular body, injected with adhesive and sealed, and then formed with this rectangle. Hollow fiber membrane modules have also been proposed in which an annular body is extracted and bonded by injecting a flexible adhesive such as urethane or silicone into the annular gap formed.

However, this method cannot prevent peeling of the outer periphery of each hollow fiber end.

This kind of delamination occurs not only during module manufacture, but also during use, especially when exposed to temperature changes when heat sterilization is performed or cold water is used to process and clean relatively high-temperature liquids. Peeling often occurred due to the difference in expansion-contraction rate of the adhesive. Peeling occurs not only between the case and the adhesive, but also at the portion where the individual hollow fibers are adhesively sealed, that is, at the outer periphery of each hollow fiber.

Such peeling of the hollow fiber membrane module causes a fatal trouble in practical use.

This is because in a system that uses many hollow fiber membrane modules, if even just one module is in this condition, it takes time to find the problem, and even if the leaking module is replaced, the contaminated system It will take a long time to clean.

Particularly in liquid processing equipment for the purpose of sterilization, even a small leakage causes a problem because even a small amount of leaked bacteria will multiply, spreading contamination to the entire system.

In view of this situation, the present inventors have completed the present invention as a result of intensive studies.

(Structure of the Invention) That is, the present invention is based on the method of “filling a cylindrical case with a hollow fiber bundle,
This is a hollow fiber membrane module in which the hollow fiber bundles and between the ends of the hollow fiber bundles and the case ends are adhesively sealed with an adhesive, and the composition of the adhesive in the adhesive sealing part is the same as the length of the module. A hollow fiber membrane characterized in that a flexible adhesive, a non-flexible adhesive, and a flexible adhesive are arranged in layers in this order from the ends in the longitudinal direction toward the center of the module. module.

”.

The key point of the present invention is that the adhesive sealing portion of the hollow fiber membrane module, particularly the corner part of the adhesive sealing portion of the cylindrical case and the individual hollow fibers, is made flexible by providing flexibility to the case and the adhesive sealing portion. The initiation of delamination between the sealing part and around the ends of the individual hollow fibers can be prevented, thereby preventing delamination in its entirety or even in areas of non-flexible adhesive. Even if this occurs, the flexible adhesive part will not be
By playing the role of king, we ensured that nothing was overlooked.

Non-flexible epoxy adhesives have very high tensile strength and strong adhesion, but are relatively weak against tearing forces such as cracking forces. Therefore, the peeling between the case and the adhesive-sealed part starts from the contact point between the case and the exposed part of the adhesive-sealed part, where the adhesive force is weak, and the outer periphery of each hollow fiber, and gradually propagates to the inside. To go.

However, flexible adhesives are extremely resistant to tearing forces, so by covering this contact area with flexible adhesives, the disadvantages of non-flexible adhesives can be overcome and the advantages can be achieved. It was something I tried to keep alive.

Next, the present invention will be explained in detail using FIG.

FIG. 1 is a schematic vertical cross-sectional view of an end portion showing an embodiment of a hollow fiber membrane module according to the present invention, in which 1-1 is an individual hollow fiber membrane, 2-2 is a hollow fiber membrane arranged inside the module. 3-3 is a flexible adhesive placed on the same end; 4 is a flexible adhesive;
-4 is a non-flexible adhesive sandwiched between flexible adhesives 2- and 3-3, and 5-5 is a case, which is usually made of acrylic resin, polysulfone resin, vinyl chloride resin, or FRPg#. .

In Fig. 1, if there are no flexible adhesives 2-2 and 3-3, that is, in the case of a conventional hollow fiber membrane module, peeling may begin between the adhesive and the case. The portions correspond to the entire inner circumference of the case corresponding to four locations of the non-flexible adhesive 4-4: the upper right corner, the upper left corner, the lower right corner, and the lower left corner.

However, as shown in Figure 1, the non-flexible adhesive 4-4
If the flexible adhesives 2-2 and 3-3 are placed on both sides of the flexible adhesives 2-2 and 3-3, the above-mentioned initiation of peeling is suppressed, and even if peeling occurs, the flexible adhesives 2-2 and 3-3 It acts as a backing and prevents leakage.

Since peeling occurs not only between the adhesive and the inner periphery of the case, but also between the adhesive and the outer periphery of each hollow fiber, the peeling prevention effect or backing effect of flexible adhesives 2-2 and 3-3 is similar. Demonstrated.

The flexible adhesive used in the present invention is defined by its chemical properties as adhesives with urethane bonds, adhesives with siloxane bonds, epoxy adhesives with natural rubber or synthetic rubber skeletons, and dimer acid skeletons. An epoxy adhesive that has a

In addition, when defining the flexible adhesive described in the present invention in terms of physical properties, the hardness after curing is 65 or less on the Sheer hardness and the elongation rate is 2.
It should be about 0% to 200%.

Incidentally, the elongation rate of epoxy resin adhesive, which is a non-flexible adhesive commonly used in the past, is at most 5 inches.

Next, we will discuss the quantitative ratio of each adhesive when the adhesives are arranged in layers in the order of flexible adhesive - non-flexible adhesive - flexible adhesive.

Generally, when the end of a hollow fiber membrane module is sealed with an adhesive, the amount of adhesive is calculated and injected so that the length is 20 to 100 fi from the end of the module.

The bonding length is appropriately selected depending on the size of the module, especially the inner diameter of the cylindrical case and the filling rate of the hollow fibers.

If this adhesive length is too short, even if the above-mentioned peeling does not occur, the module will not be able to withstand the pressure applied to the module during operation, which is 1 to 10 kg/i even in the case of ultrafiltration. Otherwise, the adhesive part will break. Furthermore, if this length is made longer than necessary, the effective filtration area of the hollow fibers will decrease, reducing the efficiency of the entire module.

Within this bonding length, the bonding length of the flexible adhesive disposed on both sides of the non-flexible adhesive is preferably 1 to 10 inches of the bonding length of the non-flexible adhesive. Therefore, it is 2 to 20 inches on both sides.

(Effects of the Invention) The hollow fiber membrane module according to the present invention has a lower case than a conventional hollow fiber module by sandwiching the non-flexible adhesive of the adhesive sealing part between flexible adhesive layers. The peel strength between the adhesive seal and the adhesive sealing part was significantly improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic vertical cross-sectional view of the end adhesive sealing part showing an embodiment of the hollow fiber membrane module according to the present invention, in which 2-2 and 3-3 are on both sides of the non-flexible adhesive 4-4. It is a flexible adhesive placed on the Patent Applicant: Daicel Chemical Industries, Ltd. Figure 1 Proceedings (spontaneous) January 14, 1985 - Date 1, Incident Indication, Senior, ;'P'' December 1980
Patent a (1) 2 filed on April 28th, Name of the invention Hollow fiber membrane module 3, Relationship with the person making the amendment Case Patent applicant and detailed description of the invention σ% \, Next: Next, the present invention will be explained in detail using Examples and Comparative Examples.'' (b) Specification letter, page 2, line 8, page 3, line 1, page 3, line 15, page 4, line 1, page 4, line 13, page 6, line 6, line 7 pH, line 16, line 17, page 7, line 16, line 17, pH line 8, line 2, page 8, line 5,
8th line, 9th line, 11th line, 16th line, page 9, line 7, line 10, page 10, line 9, page 11, line 1, line 2 "...Flexibility..." is corrected to "...Flexibility...". (c) Next to (a) above, the examples in Attachment 2 and the comparative examples in Attachment 3 will be added in sequence. b) Correct the bow 1 line in Figure 1-1 as shown in Attachment 4. Attachment 1 2. Claims (1) A cylindrical case is filled with hollow fiber bundles, and the spaces between the inner fiber bundles and between the ends of the hollow fiber bundles and the ends of the case are adhesively sealed. The adhesive composition of the adhesive sealing part is a flexible adhesive, a non-flexible adhesive, and a flexible adhesive from the longitudinal end of the module toward the center of the module. 1. A hollow fiber membrane module characterized by being arranged in a layered manner based on a thermoplastic adhesive. (2) The hollow fiber membrane module according to claim (1), wherein the flexible adhesive is an adhesive having a urethane bond. (3) Claim No. (1) in which the flexible adhesive is an epoxy adhesive having a natural rubber or synthetic rubber skeleton.
The hollow fiber membrane module described in Section 1. (4) The hollow fiber membrane module according to claim (1), wherein the flexible adhesive is an epoxy adhesive having a dimer acid skeleton. (5) A hollow fiber membrane module according to claim (1), wherein the flexible adhesive is an adhesive having siloxane/bond. Attachment 2 Example A fiber bundle consisting of 6,400 polyethersulfone hollow fibers with an inner diameter of 500 F'' and an outer diameter of 700 pH1 was inserted into a polysulfone case with an inner diameter of 82 mm, an outer diameter of 90 m+φ, and a length of 320 mm. The thickness of the flexible adhesive layer after opening and trimming the ends of the hollow fibers was set in the adhesive sealing device at a temperature of 55°C and a rotation speed of 800 rpm until the thickness of the flexible adhesive layer was 1 haze at the minimum part. Inject the urethane adhesive until it hardens, then inject the epoxy adhesive, which is a non-flexible adhesive, to a thickness of 23cm and let it harden.Then, make the flexible adhesive again. The thickness of the urethane adhesive is 1-
It was injected and allowed to harden. In the medium 9-thread type pancreatic module manufactured by the above procedure, the adhesive sealing part is arranged in layers in the length direction of the module by the force of exchangeable adhesive - non-flexible adhesive - adhesive adhesive. The thickness of each layer of adhesive is 1 x 23 x 1 x 1. After taking it out and cutting off the end of the case, I inspected the module for leaks, but no leaks were found. After passing hot water at 80° C. through this hollow fiber type module for 30 minutes, the hot water was immediately removed and cold water at 10° C. was passed through it for 30 minutes, but peeling occurred between the case and the adhesive. Attachment 3 Comparative example Polysulfone case with inner diameter 82fiφ, outer diameter 90■φ, length 320゛, inner diameter 500p-, outer diameter 700pm
A fiber bundle consisting of 6,400 polyether sulfone hollow fibers was pushed in, set in a centrifugal sealing machine, and the thickness of the case and adhesive layer was 25 m at a temperature of 55°C and a rotation speed of 80 Orpm. Similarly, a non-flexible epoxy adhesive was injected, centrifugally sealed, and cured. After taking it out and cutting off the end of the case, we performed a leak test on the module, but found no leaks. After passing hot water at 80° C. through this hollow fiber membrane module for 30 minutes, the hot water was immediately removed and when cold water at 10° C. was passed through it, peeling occurred between the case and the adhesive. In addition, there were some modules that peeled off simply by passing hot water at 80°C.

Claims (1)

[Claims] (1) A cylindrical case is filled with hollow fiber bundles, and the hollow fiber bundles are adhesively sealed between the hollow fiber bundles and between the ends of the hollow fiber bundles and the ends of the case. It is a thread-type membrane module, and the adhesive composition of the adhesive sealing part is a flexible adhesive, a non-flexible adhesive, and a flexible adhesive from the longitudinal end of the module to the center of the module. A hollow fiber membrane module characterized by being arranged in layers in the following order. (2) The hollow fiber membrane module according to claim (1), wherein the flexible adhesive is an adhesive having a urethane bond. (3) Claim No. (1) in which the flexible adhesive is an epoxy adhesive having a natural rubber or synthetic rubber skeleton.
Hollow fiber membrane module (4) The hollow fiber membrane module according to claim 1, wherein the flexible adhesive is an epoxy adhesive having a dimer acid skeleton. (5) The hollow fiber membrane module according to claim (1), wherein the flexible adhesive is an adhesive having a siloxane bond.