JPH09262442A - Hollow fiber membrane integrated module and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To decrease damages in hollow fiber membranes by independently and directly potting two or more hollow fiber membrane bundles of many hollow fiber membranes into two or more fitting holes arranged in lines on a plate equipped with a passage for a filtrate, air diffusing holes and passages for air. SOLUTION: The ends of two or more hollow fiber membrane boundles 2 of many hollow fiber membranes are directly and independently fixed with a potting material 14 to two or more fitting holes 19 of a plate 1 equipped with a passage 12 for filtrate, air diffusing holes and passage for air. The end of the hollow fiber membrane bundle 2 facing the passage 12 of the filtrate is made open. The potting material 14 is preferably a thermosetting resin such as an epoxy resin and urethane resin. Thereby, damages in the hollow fiber membrane are very little and the module can be produced by a simple assembling method, and it can be industrially mass-produced at a low cost.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hollow fiber membrane integrated module for filtering a liquid containing a large amount of a substance to be removed such as activated sludge water, and particularly to a filtration system using both air diffusion and filtration. For modules suitable for.

[0002]

2. Description of the Related Art When a liquid containing a large amount of substances to be removed such as activated sludge water or sewage is filtered under pressure, the filter is significantly clogged. However, the combined use of aeration and suction filtration significantly improves the clogging. To be done. For the purpose of making this filtration system effective, a hollow fiber membrane bundle having one free end is horizontally arranged so that the hollow fiber membrane oscillates due to rising bubbles (for example, JP-A-4-180821). Gazette), the free end of the hollow fiber membrane is extended from the fixed end to the other end in an umbrella shape (for example, Japanese Patent Laid-Open No. 4-187219), and the hollow fiber membranes are bundled into a comb shape and one or both ends thereof are fixed. (For example, JP-A-6-340, JP-A-6-342, JP-A-6-344, and JP-A-7-24272), several types of membranes in which the arrangement of hollow fiber membranes is devised The module is being developed. However, these modules are complicated in structure and therefore complicated to assemble.

In the filtration of highly polluted liquids, it is known that when the filtration rate is increased, the clogging is generally severe and the life of the membrane is extremely shortened. Therefore, in practice, filtration at a low filtration rate is usually performed, but this increases the required membrane area and inevitably requires a larger module.

The production of a module using these hollow fiber membranes always includes a process of focusing and fixing a yarn bundle called potting. A hollow fiber membrane that is once potted to a simple shape because a large bundle of complicated shapes cannot be potted because the bundle of threads is fixed and integrated with resin and the opening of the hollow fiber is formed by cutting it partially. The unit is made into one part and assembled to make a module.

The potted hollow fiber loses the degree of freedom correspondingly, and is very weak in the axial direction and the bending direction. Therefore, the method of assembling the hollow fiber after it is potted causes damage to the hollow fiber, and naturally the work must be very careful. Similarly, when retrofitting equipment such as an air diffusing pipe, the same complicated and careful work is required.

Recently, a method of potting hollow fiber membranes bundled in a comb shape into a water collecting pipe has been developed, but this is still one part constituting a module, and the above-mentioned problems are caused in the subsequent assembling process. Is included. That is, the manufacturing method in which the hollow fiber membrane unit is separately manufactured and the module is assembled has an inherent cause of the breakage of the hollow fiber, and is a careful operation. The complexity of the production is not suitable for mass production.

Further, conventionally, there is no module that can withstand backwashing in the filtration system using both air diffusion and filtration.

[0008]

The problem to be solved by the present invention is a hollow fiber membrane module having a structure suitable for suction filtration of highly polluted liquid and capable of backwashing and having a large membrane area. It is an object of the present invention to develop an inexpensive and industrially mass-producible hollow fiber membrane integrated module which is manufactured by a simple assembling method with a very low possibility of being damaged. Moreover, it is also to provide the manufacturing method together.

[0009]

[Means for Solving the Problem] By allowing air bubbles to flow along the fiber axis direction of the hollow fiber membrane, avoiding cutting of the hollow fiber membrane,
In an integrated module in which a hollow fiber membrane module and an air diffusing device are integrated so as to withstand the backwashing of the hollow fiber membrane while satisfying the air diffusion effect, the hollow fiber membrane is directly potted to the module. If possible, the above problems can be solved.

That is, according to the present invention, (1) a hollow fiber membrane having a simple structure in which a potting portion of a bundle of hollow fiber membranes, a passage for a filtrate, a diffuser hole, and an air passage are integrated on one plate. The integrated module is (2) in its assembly method,
(3) A hollow fiber membrane integrated module having a structure in which the hollow fiber membrane bundle is directly potted in a mounting hole on the plate, and (3) the plate is integrally molded and has a structure that can withstand backwashing.

The present invention also provides (4) the hollow fiber membrane integrated module having the above-described structure, wherein when potting the hollow fiber membrane bundle into the mounting hole on the plate, the potting portion of the mounting hole is subjected to corona discharge treatment. This is a method for manufacturing a hollow fiber membrane integrated module.

[0012]

1 is a simplified front view showing an embodiment of the hollow fiber membrane integrated module of the present invention, and FIG. 2 is a side view thereof. FIG. 3 is a sectional view taken along line AA of FIG.

In these figures, the hollow fiber membrane bundles 2 are arranged in two rows on the integrated plate 1, but three or more rows are also possible. The plate 1 has air diffuser holes 3 near the hollow fiber membrane bundle 2.
And there is a filtrate outlet 4 and an air inlet 5 on the side surface. Further, the flow holes 6 for the liquid to be treated which penetrate the plate 1 vertically are arranged substantially evenly on the plate. Inside the plate 1, there is formed a filtrate passage 12 which communicates with the hollow fiber membrane bundle 2 and the filtrate outlet 4, and an air passage which communicates with the air diffuser 3 and the air inlet 5. 13 is formed in a system separate from the passage 12 for the filtrate.

At the four corners of the plate 1, the foot 10 and the support frame 1 are provided.
0a is fixed. Also, the support frames 10a, 10a
A support member 9 for the hollow fiber membrane bundle 2 is laterally provided between the upper ends of the
The central member of the hollow fiber membrane bundle 2 is hooked on the support member 9 and an air guide plate 11 is fixed between the support frames 10a and 10a.

The plate 1 is injection-molded with a thermoplastic resin. The thermoplastic resin only needs to have mechanical strength and durability against the liquid to be treated and the cleaning liquid. Polyvinyl chloride, which is generally easy to bond in assembly, is also suitable in the present invention, but since the present invention directly pots a hollow fiber membrane bundle, polypropylene having excellent moldability is more preferred. It can also be made of metal.

Considering the pressure loss of the filtrate, the length of the hollow fiber membrane should be short when the inner diameter of the hollow fiber membrane is small and long when it is thick. In the present invention, a hollow fiber membrane having an inner diameter of 300 to 500 μm is used in order to effectively swing the entire hollow fiber membrane, so the length of the hollow fiber membrane per bundle is approximately 25 to 100 cm.

The pore diameter of the hollow fiber membrane is about 0.1 to 0.5 μ.
m, a known hollow fiber membrane made of polysulfone, polyethylene, polypropylene or the like can be used in the present invention.

FIG. 4 is a simplified view of a section taken along the line BB in FIG. 3 to show the structure of the potting portion. Hollow fiber membrane bundle 2
Are fixed to the plate 1 by the potting material 14. That is, the plate 1 has a passage 12 for the filtrate.
The two or more mounting holes 19 communicating with each other are linearly arranged and formed, and the end portions of the hollow fiber membrane bundle 2 are focused and fixed by the potting material 14 in the mounting holes 19, and the filtrate of the hollow fiber membrane bundle 2 is filtered. The end surface facing the passage 12 is an opening.

FIG. 5 is a schematic view showing a state before the hollow fiber membrane bundle 2 is potted to the plate 1. Liquid transfer tray 1
5 is attached to the tunnel which will later become the passage 12 for the filtrate, and the surface 2 of the attachment hole 19 for fixing the hollow fiber membrane bundle 2
0 is subjected to corona discharge treatment. Further, the liquid feeding tray 15 is provided with a potting agent injection port 16. The potting agent is injected from the injection port 16 in the state of FIG. 5, and the gap and the mounting hole at the end of the hollow fiber membrane bundle 2 are attached. Satisfy 19. Then, as shown in FIG. 6, after the potting agent has hardened, the liquid feed tray 15 is pulled out from the tunnel that serves as the filtered liquid passage 12 of the plate 1. Note that FIG. 7 or FIG.
7 shows a cross section of a tunnel which will later become the passage 12 of the filtrate, having a quadrangular shape, and FIG. 8 shows a circular shape. Then, insert a cutter as shown in FIG. 9 or FIG. 10 into the tunnel that serves as the passage 12 for the filtrate,
At the same time as forming the hollow fiber opening, the passage 12 for the filtrate is formed.

When the cross section of the filtrate passage is rectangular as shown in FIG. 7, the filtrate passage is formed by using a cutter as shown in FIG. When the sectional shape is circular as shown in FIG. 8, a cylindrical cutter as shown in FIG. 10 is used. In the cutter shown here, the cutter blade 17 is used for the filtrate passage 1.
It has a structure fixed to a cutter handle 18 having the same cross-sectional shape as 2, and the blade edge of the cutter blade 17 is inclined with respect to the longitudinal direction of the cutter handle 18. In the case of a cylindrical cutter, the hollow fiber opening can be formed while inserting the cutter while rotating it counterclockwise to reduce the force applied to the potting portion and prevent the occurrence of defects due to peeling. . The aspect shown here is an example.

A thermosetting resin such as an epoxy resin or a urethane resin is preferably used as the potting agent. The viscosity of the resin is 1 to 2 Pa · s when compounded, the tensile strength after curing is 150 to 400 kgf / cm ² , and the elongation is 50 to
150% is preferable.

Next, an example of a method for manufacturing this module will be described. First, the foot 10 and the support frame 10 are attached to the stacking plate 1.
a, the support member 9 is assembled. Next, the hollow fiber membrane bundle 2 is set at a predetermined position and potting work is performed. Finally, the air guide plate 11 is attached. In this method, no change in shape or force is applied to the hollow fiber after potting.

Since the hollow fiber membrane integrated module of the present invention is used for immersion filtration of activated sludge treated water containing a large amount of substances to be removed as described above, even if air diffusion and suction pressure filtration are used together, Clogging is inevitable. In such a case, backwashing is effective for recovering the filtration performance, but the conventional device is not always structured to withstand backwashing. However, the hollow fiber membrane module of the present invention has a structure that can withstand backwashing pressure, and can be backwashed with a filtrate and backwashed with air.

[0024]

EXAMPLES Next, the present invention will be described more specifically by way of examples, but the present invention is not limited to the following examples.

The length, width and thickness are 80 cm and 20 respectively.
cm and 7 cm polypropylene plates 1 and two passages 12 for the filtrate having an inner diameter of 30 mm that penetrate the plates.
Rows, 4 rows of air passages 13 with an inner diameter of 10 mm, 16 hollow fiber attachment holes 19 having a diameter of 20 mm for fixing the hollow fiber membrane bundle while being connected to the filtration fluid passages 12 at 4 cm intervals, and a diameter of 2 mm connected to the air passages. The diffuser holes 3 are provided on the both sides of the mounting hole 19, the flow holes 6 for the liquid to be treated having a diameter of 30 mm, the feet 10 for placing the plates at the four corners, and the holes having a diameter of 11 mm for fixing the support frame 10a. The hollow fiber membrane integrated module plate 1 was prepared by injection molding.

The surface 20 of each mounting hole 19 of this plate 1
After the corona discharge treatment, the support member 9 made of stainless steel and having a diameter of 10 mm and having a length of 76 cm is fixed. 10 and fixed. Separately, the inner and outer diameters are 500μm and 800μ
Hollow fiber membrane bundle 2 in which 400 hollow fiber membranes made of polysulfone having a diameter of m, a length of about 150 cm and a pore diameter of about 0.45 μm are bundled.
16 sets were prepared.

Diameter 30 mm, width and depth 20 m
A polypropylene liquid feed tray 15 having a groove length of m and 15 mm and having a length of about 40 cm was inserted and fixed from both sides of the filtrate passage 12 of the integrated plate 1 with the groove 15a being the hollow fiber mounting hole 19 side. . The central part of the hollow fiber membrane bundle 2 was hooked on the support member 9, and both ends were inserted into the mounting holes 19, respectively.

Next, a urethane resin having an initial viscosity of 1500 mPa.s is used as the potting agent injection port 1 of the liquid feed tray 15.
The injection was performed from 6 to about 30 minutes. After leaving it as it was overnight, the liquid feed tray 15 was pulled out, a cutter on a cylinder having a diameter of about 25 mm was inserted to form a hollow fiber opening, and the passage 12 of the filtrate was regenerated. A filtrate plug 7 was provided at one end of the filtrate passage 12 and a filtrate outlet 4 was provided at one end. Similarly, the openings of the air passages 13 other than the air introduction port 5 were closed by the air plugs 8.

(Backwash test) Vertical, horizontal and height are all about 1 m
Put the hollow fiber membrane integrated module into the water tank of (1) 5k
Suction filtration was performed at a pressure difference of Pa for 10 minutes to completely wet the hollow fiber membrane with water. Then, (2) Air was sent from the filtrate side, the pressure was increased to 200 kPa, and the pressure was maintained for 5 minutes. No air bubble leakage was detected from the hollow fiber membranes and plates. Then, when the pressure was increased to 400 kPa, the bubble point of the hollow fiber membrane was reached, air bubbles spouted from the entire hollow fiber membrane, and the pressure dropped. The operations (1) and (2) were performed again, but no leakage of air bubbles from the hollow fiber and the plate was found.

[0030]

EFFECTS OF THE INVENTION According to the hollow fiber membrane integrated module of the present invention as described above, highly polluted liquid can be suitably filtered by using both aeration and suction filtration, and the filtration capacity can be improved by backwashing. Can be recovered. Further, according to the method for manufacturing a hollow fiber membrane integrated module of the present invention, there is very little possibility of breakage of the hollow fiber membrane, and the hollow fiber membrane can be manufactured by a simple assembling method. A manufacturing method can be provided.

[Brief description of drawings]

FIG. 1 is a front view of a hollow fiber membrane integrated module of the present invention.

FIG. 2 is a side view thereof.

FIG. 3 is a sectional view taken along line AA of FIG. 1;

FIG. 4 is a simplified cross-sectional view taken along the line BB of FIG.

FIG. 5 is a schematic cross-sectional view showing a state in which the liquid feed tray is mounted before potting the hollow fiber membrane bundle.

FIG. 6 is a schematic cross-sectional view showing a state in which the liquid feeding tray is removed after the potting agent is cured.

FIG. 7 is a sectional view taken along line CC of FIG. 5;

8 is a cross-sectional view taken along the line CC of FIG. 5, which is a cross-sectional view of another aspect.

9 is a perspective view of a cutter tip end portion corresponding to the cross-sectional shape of the filtrate passage of FIG. 7. FIG.

10 is a perspective view of a cutter tip end portion corresponding to the cross-sectional shape of the filtrate passage of FIG.

[Explanation of symbols]

 1 Integrated Plate 2 Hollow Fiber Membrane Bundle 3 Diffusion Hole 4 Filtrate Liquid Outlet 5 Air Inlet 6 Flow Port of Treated Part 7 Filtration Liquid Plug 8 Air Plug 9 Supporting Member 10 Feet 10a Support Frame 11 Air Guide Plate 12 Filtration Liquid Passage 13 Air Passage 14 Potting Material 15 Liquid Transfer Tray 15a Groove 16 Potting Agent Injection Port 17 Cutter Blade 18 Cutter Handle 19 Hollow Fiber Membrane Bundle Mounting Hole 20 Surface of Mounting Hole

Claims (6)

[Claims] 1. Two or more hollows in which a large number of hollow fiber membranes are bundled in two or more linearly arranged mounting holes on a plate having a filtrate passage, an air diffusion hole, and an air passage. A hollow fiber membrane integrated module, wherein the fiber membrane bundles are directly potted independently of each other. 2. The hollow fiber membrane integrated module according to claim 1, wherein the plate is manufactured by integral molding. 3. The hollow fiber membrane integrated module according to claim 1, wherein the positive pressure resistance of the filtrate passage is 100 kPa or more. 4. Two or more hollows in which a large number of hollow fiber membranes are bundled into two or more linearly arranged mounting holes on a plate provided with a passage for filtrate, an air diffusion hole, and an air passage. A method for producing a hollow fiber membrane integrated module in which fiber membrane bundles are directly potted independently of each other, wherein the potting portion of the mounting hole of the plate is subjected to corona discharge treatment. Method. 5. The method for manufacturing a hollow fiber membrane integrated module according to claim 4, wherein the plate is integrally molded. 6. The method for producing a hollow fiber membrane integrated module according to claim 4, wherein the positive pressure resistance of the filtrate passage is 100 kPa or more.