JPH02227125A - Hollow fiber-shaped filter cartridge - Google Patents

Abstract

PURPOSE:To drastically enhance filter performance and resistance to pressure by providing a supporter for reinforcement to a heater part and making the header part compact and making the occupied volume of a hollow fiber-shaped filter large. CONSTITUTION:Many hollow fiber 38 housed in a perforated cylinder 37 are fixed to a potting part 39 together with the cylinder 37. A header 31 is fixed to the potting part 39 and four pieces of supporters 32 for reinforcement are radiately fixed to the inside rear surface and also a gasket 35 is fitted. Raw liquid is passed through the holes of the cylinder 37 for a cartridge 30 fitted to a housing and brought into contact with the outer surfaces of the hollow fibers 38. The raw liquid is passed to the inner surfaces from the outer surfaces thereof. Filtrate is passed through the inner surfaces of the hollow fibers and allowed to flow out from the aperture face of the potting part 39. Thereafter filtrate is passed through the gap between the aperture face and the header 31 and passed through an outlet 33 and taken out to the outside of the housing. Thereby resistance to pressure is enhanced and also the occupied volume of the header part is made small and thereby the occupied volume of the hollow fiber-shaped filter can be made large.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a hollow fiber filter cartridge for precision filtration.

[Conventional technology] Conventionally, as a filter cartridge for precision filtration,
Disc-type filter cartridge (G) shown in Figure 4
, and pleated filter cartridges shown in FIGS. 5 and 6 are known. In Figure 4, 01) is the head ladder, day is the O-ring, (5) is the end cap, (
) is a membrane disk. In FIGS. 5 and 6, (2N) is a header, (2N) is a furnace liquid passage, (2) is a sealing material, (2) is an end cap, (2) is a perforated cylinder, and (2) is a pleated membrane filter.

These types of filter cartridges (A) and ① are used to remove substances with a size of approximately 0.2 or more, but as the pore size of the filter becomes smaller, the purification pressure increases rapidly with these types. There is a problem with getting bigger.

Hollow fiber filter cartridges are also known as more precise filter cartridges (for example, JP-A-82-74408, JP-A-83-315105, JP-A-83-315108, etc.). These types can remove substances of O,1JJI+1 or less, but these hollow fiber filter cartridges have two liquid passages in the center of the hollow fiber bundle, and have a large volume to provide pressure resistance. Since shaped headers and end caps are used, the volume occupied by the hollow fiber filter is small, and the relationship between filtration accuracy and filtration speed cannot be said to be significantly improved compared to pleated types.

[Problem to be Solved by the Invention] In a hollow fiber filter, when filtration is performed from the outside of the hollow fiber to the inside, when the filtration speed per unit length of the hollow fiber increases, the amount of water flowing inside the hollow fiber increases. The pressure loss of the liquid also increases. Therefore, even if the number of filled threads is increased by making the threads thinner and the area occupied by the filter is increased, the amount of filtration does not necessarily increase. Rather, it is preferable that the hollow fibers be thicker so that the pressure loss of the liquid does not impede the filtration rate.

On the other hand, when the hollow fibers become thicker, the area occupied per unit volume does not become significantly larger than that of pleated fibers. Therefore, unless the structure of the cartridge is such that the volume occupied by the hollow fiber filter is as large as possible, the filtration performance (the relationship between filtration accuracy and filtration speed) cannot be significantly improved compared to pleated filters or the like.

As mentioned above, the volume occupied by the conventional hollow fiber filter cartridge cannot be said to be large.

The inventor of the present invention made the hollow fibers thick so that the pressure loss of the furnace liquid would not interfere with the filtration rate, and did not use any special two-way liquid passages in the bundle of hollow fibers. The present inventors have discovered that the filtration performance can be significantly improved by making the volume occupied by the hollow fibers as large as possible by reducing the volume occupied by the hollow fibers, and have completed the present invention.

[Means for Solving the Problems] In the hollow fiber filter cartridge of the present invention, one end of the hollow fiber is housed in an effective cylinder and is sealed or folded back into a loop shape, and the other end is sealed together with the cylinder using a botting agent. Hollow fiber filter cartridges that are fixed to each other without any gaps and have open ends,
A header having reinforcing struts for preventing deformation due to pressure is fixed to the opening side.

The hollow fiber filter used in the present invention has a water permeation rate of approximately 1000 to 2000 ON/rrr-hr-k
g/cIJ. 1000I/ko・hr-kg
/C, the effective filter area can be increased without considering the pressure loss of the liquid by making the hollow fibers thinner without particularly increasing the volume occupied by the hollow fibers. Can be done. On the other hand, 20000j! / r
If it is larger than rr-hr ・kg/c-,
In order to reduce the liquid pressure loss, the hollow fibers are thicker,
Even with the cartridge structure of the present invention, the effective filter area is comparable to that of pleated filters, etc., and the filtration performance is also comparable. The inner diameter of the hollow fibers used in the present invention is approximately 300 to 700 mm for the reasons described above.

Further, the separated particle diameter of the hollow fiber filter used in the present invention is about 0.1 J1 or less, and the molecular weight cutoff is about 50,000 or more.

The material constituting the cartridge, including the hollow fiber filter, is preferably one with excellent heat resistance, chemical resistance, and mechanical properties. For example, preferred materials for hollow fiber filters include polysulfone, polyethersulfone, and polypropylene. These materials are also preferably used for the perforated cylinder, header, and end cap. Further, it is preferable to use a tough epoxy resin as the botting agent.

[Example] Next, the hollow fiber filter cartridge of the present invention will be specifically explained based on the drawings.

"Figures 1 to 3 show specific examples of the hollow fiber filter cartridge of the present invention, which is compatible with conventional disk type (Figure 4) or pleated type (Figures 5 and 6).

One end of a large number of hollow fibers (38) housed in a perforated cylinder (37) is folded back into a loop shape, and the other end (38a) is fixed to the cylinder (37) with a strong botting agent without any gaps. Moreover, the tip thereof is open. The header (31) is fixed with a botting part (39), preferably with the same botting agent. Four reinforcing columns (32) are radially fixed to the inner lower surface of the header (31). The lower part of this reinforcing column (32) is formed at an acute angle so that there is no hollow fiber (38) that covers all of the opening, and is in contact with the opening with a faceted shell. Note that there is a space between adjacent reinforcing columns (32), which is a gap (34).

A sealant (35) (a flat gasket is used in FIG. 1, and an O-ring is used in FIG. 3) is attached to the header (31). Cartridge (30
) has a perforated end cap (3B) in Figure 1.
In FIG. 3, imperforate end caps (36) are each secured to a perforated cylinder (37).

In FIG. 1, the housing (not shown) for mounting the cartridge (2) is shown with a fixing protrusion that passes through the hole in the end cap (3B).
The hollow fibers (38) in the center are short.

Next, how to use these cartridges will be explained. With the cartridge installed in the housing (not shown), the concentrate passes through the holes in the cylinder (37) and into the hollow fiber (38).
touches the outer surface of The purified liquid that has passed from the outer surface to the inner surface of the hollow fiber (38) passes through the inner surface of the hollow fiber and reaches the botting part (
39) flows out from the opening surface. This furnace liquid passes through this opening surface and the gap (34) of the header (31), and passes through the purified liquid outlet (33) of the cartridge, which is connected to the purified liquid outlet of the housing by the sealing material (35) without any leakage, to the housing. taken outside.

Only a few gaps (34) are required, and the structure of the present invention can improve pressure resistance, reduce the volume occupied by the header portion, and increase the volume occupied by the hollow fiber filter.

Next, the effects of the present invention will be specifically illustrated by examples.

Example 1 Polysulfone (Amoco, needle polysulfone P-3
500), polyethylene glycol, propylene glycol and N-methyl-
A spinning stock solution consisting of 1B, 13, 3, 8, 7 and 60% by weight of 2-pyrrolidone, respectively, was extruded at 60°C through a double tubular nozzle together with propylene glycol as a core solution.
After running 15 times in the air, it was immersed in warm water at 60°C, and then wound up into a loop at a speed of 50 a/min.

This was washed with hot water and then dried. The inner and outer diameters of the hollow fibers were 470a+ and 700f, respectively. This hollow fiber did not pass uniform latex particles having a particle size of 0.038 gn. In addition, the water permeation rate based on the outer surface measured using a hollow fiber with a length of about 30 cm is 20°
C 4900II/rd・hr・kg/c-
Met.

3800 hollow fibers (however, if one end is folded back into a loop, each hollow fiber is counted as 2 fibers)
A hollow fiber filter cartridge shown in FIG. 3 was prepared using the above method. The perforated cylinder has an inner diameter 6 with an axial compressive modulus of elasticity of 4340 kg/c and 550 kg/c at a load of approximately 50 kg at 23°C and 120°C, respectively.
A lattice-shaped polypropylene cylinder with an outer diameter of 70 am was used. A polypropylene end cap approximately 5 mm thick was fused to the perforated cylinder (38). The other end of the hollow fiber bundle was fixed with an epoxy resin together with a perforated cylinder by centrifugal casting. The epoxy resin used here is ASTM
- When measured by a method similar to D638, the tensile modulus, maximum stress and maximum strain at 120°C are each 1
22kg/m (,4,00kg/mat and 8.7
It was a strong 5%. Next, the above-mentioned fixing part was cut so that the length of the fixing part was about 13 + a + i to open the hollow fiber. At this fixed part, the height is 5N, the bottom is 6
A reinforcing column with a triangular cross section with a width of 0.3 mm at the tip (
A ladder ladder (31) made of polysulfone (needle polysulfone P-1700) having four pieces of 32) was adhered using the same epoxy adhesive as above. The thus obtained hollow fiber filter cartridge ■ has an end cap (3B
) The length from the bottom of the header (31) to the shoulder of the header (31) was 250 fins, and the length of the hollow fiber with holes was 220 fins.

Next, this cartridge was installed in a pleated stainless steel housing with a diameter of 3 inches and a length of 10 inches, and the water permeation rate and resistance to steam sterilization were examined. As a result, the water permeation rate was 1 ON/min at 25°C and a filtration pressure of 0.1 kg/c-. Also [Validation of filtration sterilization process, Yakugyo Jihosha, 1985.86-B7 pages]
As a result of repeating the above sterilization operation 5 times according to the method described in , there was no change in the appearance of the cartridge, no leakage occurred, and no change was observed in the filtration rate.

Example 2 The first step was carried out in the same manner as in Example 1 except that a 30 weight percent N-methyl-2-pyrrolidone aqueous solution was used as the core liquid.
A hollow fiber filter cartridge (2) shown in the figure was prepared. However, this hollow fiber (38) has a water permeation rate of 1500
! l/rrr·hr·kg/c-, and was impermeable to pyrodiene substances in tap water.

The water permeation rate of this cartridge ■ is 25℃, 0.45kg
/cj under pressure of 101/min.

Next, using this cartridge, a particle size of approximately 0.1.
s polystyrene latex with Tween 20 (Wako Tsumugi ■) 0. A solution prepared by dispersing 5ffi in a 1% lff aqueous solution was filtered at a pressure of 5 kg/c-, but no latex particles were detected in the solution.

[Effects of the invention] By providing a reinforcing strut in a part of the header, the header becomes more compact and the volume occupied by the hollow fiber filter can be increased. A hollow fiber filter cartridge was obtained which had far superior filtration characteristics compared to hollow fiber filter cartridges and also had excellent pressure resistance.

[Brief explanation of the drawing]

FIG. 1 is a partially sectional front view of a disk-type filter cartridge according to an embodiment of the present invention (the cross section is taken along the line (1)-(1) in FIG. 2), and FIG. 2 shows the filter shown in FIG. 1. FIG. 3 is a partially sectional front view of a disk-type filter cartridge according to another embodiment of the present invention, FIG. 4 is a front view of a conventional disk-type filter cartridge, and FIGS. 5 and 6 are a front view of a conventional disk-type filter cartridge. FIG. 3 is a front view of the pleated filter cartridge of FIG. (Main symbols in the drawing) (31): Header (32): Reinforcement strut (34): Clearance (3B); End cap (37): Perforated cylinder (3B): Hollow fiber (39): Botting section Figure 3 Figure 4

Claims (1)

[Claims] 1. One end of the hollow fiber housed in a perforated cylinder is sealed or folded back into a loop shape, the other end is fixed to the cylinder with a potting agent without any gaps, and the tip thereof is open. 1. A hollow fiber filter cartridge characterized in that a header having reinforcing struts for preventing deformation due to pressure is fixed to the opening side. 2. The hollow fiber filter cartridge according to claim 1, wherein the outer dimensions of the header are compatible with a pleated filter cartridge or a disk filter cartridge.