JP2006247550A - Hollow fiber membrane module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a hollow fiber membrane module capable of performing stable filtering operation over a long period of time. <P>SOLUTION: The hollow fiber membrane module 10 comprises a case housing 20, a cap 11 connected with an opening end face of at least one end side of the case housing 20, and a hollow fiber membrane bundle 30 held in the case housing. The cap is constituted of a bottom face having a liquid gateway and a flank integrally formed with the bottom face and a side facing the liquid gateway is opened. A ratio of a diameter (D) of the case housing to rising average height (Hav) of a part except the liquid gateway at a cap inner face (Hav×100/D) is within a range between 35% and 70%. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a hollow fiber membrane module, and more particularly to a cap connected to an end surface opening of a hollow fiber membrane bundle.

A required number of hollow fiber membrane bundles are accommodated in a case housing having a liquid inlet / outlet, and caps are connected to both ends of the case housing so that liquid (raw water, permeated water, etc.) can enter and exit from the case housing and cap. This is a hollow fiber membrane module, and such a type is often applied to a relatively large module.
Japanese Utility Model 5-018604

  However, when such a hollow fiber membrane module is used for filtration operation, back pressure washing, etc., sludge tends to accumulate on the liquid outlet side, and the hollow fiber membrane bundle located near the liquid inlet / outlet is accumulated. May be blocked by sludge.

  It is an object of the present invention to provide a hollow fiber membrane module that can perform a stable filtration operation for a long period of time without being clogged with accumulated sludge at an end surface opening of a hollow fiber membrane bundle located near a liquid inlet / outlet. To do.

As a means for solving the problems, the present invention
A hollow fiber membrane module having a case housing and a cap connected to an opening end face of at least one end of the case housing; and a hollow fiber membrane bundle accommodated in the case housing;
The cap has a bottom surface having a liquid inlet / outlet and a side surface integrated with the bottom surface, and the side facing the liquid inlet / outlet is opened,
A hollow fiber having a ratio (Hav × 100 / D) of a diameter (D) of the case housing and a rising average height (Hav) of a portion excluding the liquid inlet / outlet on the inner surface of the cap in a range of 35% to 70%. A membrane module is provided.

  In the hollow fiber membrane module of the present invention, by connecting a cap with a specific shape, sludge is not accumulated during filtration operation, back pressure washing, etc., and the end surface opening of the hollow fiber membrane bundle is blocked. Absent.

  Therefore, the hollow fiber membrane module of the present invention can continue a stable filtration operation for a long time even when the filtration operation and back pressure washing are repeated.

  Hereinafter, the hollow fiber membrane module of the present invention will be described with reference to FIG. FIG. 1 is a longitudinal sectional view of a hollow fiber membrane module 10 of the present invention. Only a part of the hollow fiber membrane bundle is illustrated. The structure of the hollow fiber membrane module of the present invention is known except for the cap. For example, the structure shown in FIGS. 1 to 5 of JP-A-2004-89800 (excluding the cap) is used. can do.

  The cap 11 is connected to one end or both end openings of the case housing 20, and the cap on either side can have the same shape.

  The cap 11 includes a bottom surface 13 having a liquid inlet / outlet 12 and a side surface 14 integrated with the bottom surface 13, and the side facing the liquid inlet / outlet 12 is opened (opening 15). The opening 15 is connected to the opening of the case housing 20.

  The bottom surface 13 of the cap 11 and the end surface opening of the hollow fiber membrane bundle 30 accommodated in the case housing 20 are opposed to each other, and the bottom surface 13 is a flat surface or a curved surface similar thereto.

  The diameter (D) of the case housing 20 is preferably 200 mm or more, more preferably 250 mm or more, and further preferably 300 mm or more. The case housing 20 has at least one fluid inlet / outlet 21 on a side surface.

  The hollow fiber membrane bundle 30 is a bundle of hundreds to thousands of hollow fiber membranes having a diameter of about 1 mm to several millimeters, and the material of the hollow fiber membrane is not particularly limited, and a known one is used. Preferably, a cellulose acetate resin having a high detergency can be used.

  The cap 11 has a ratio (Hav × 100 / D) of 35 to 70% of the diameter (D) of the case housing 20 and the average rising height (Hav) of the portion excluding the liquid inlet / outlet 12 on the inner surface of the cap 11. Preferably it is 50 to 70%, more preferably 55 to 60%.

Here, the rising average height (Hav) of the portion excluding the liquid inlet / outlet 12 is obtained by dividing the bottom surface 13 into a total of six grids, such as the heights H ₁ and H ₂ in the cap 11 as shown in FIG. Thus, the average value of the values measured at a total of 12 points.

  Next, the operation of the cap 11 when the hollow fiber membrane module 10 is filtered will be described together with the operation of the conventional cap 50 shown in FIG. In FIG. 1 and FIG. 2, the same number means the same thing.

  During the filtration operation, sludge is accumulated on the membrane surface of the hollow fiber membrane bundle 30. When the filtration operation is stopped, washing water is injected from the liquid inlet / outlet and backwashing is performed, the soared sludge flows into the space 16 in the cap 11.

  At this time, in the hollow fiber membrane module using the conventional cap 50 of FIG. 2, the sludge that has flowed into the space 16 stays in a vortex and is not easily discharged from the liquid inlet / outlet 12. In particular, sludge stays in the vicinity of the circumference of the cap 50. For this reason, the end surface opening part of the hollow fiber membrane bundle 30 was obstruct | occluded with sludge, and it became a factor by which filtration performance fell.

  However, in the hollow fiber membrane module 10 using the cap 11 of FIG. 1, the ratio (Hav × 100 / D) is set within a predetermined range, so that the sludge that flows into the space 16 may vortex or stay. And is quickly discharged from the liquid inlet / outlet 12. For this reason, since it is suppressed that the end surface opening part of the hollow fiber membrane bundle 30 is obstruct | occluded with sludge, it can perform the stable filtration operation for a long period of time.

Example 1
A hollow fiber bundle consisting of 22,320 hollow fiber membranes each having an inner diameter of 0.8 mm, an outer diameter of 1.3 mm, a length of 1230 mm, and a cellulose acetate resin was placed in a case housing having an inner diameter of 300 mm. Then, it was adhesively sealed with a urethane-based adhesive by a centrifugal sealing machine (manufactured by Toho Machine Industry Co., Ltd., horizontal centrifugal molding machine).

  A cap as shown in FIG. 1 having a ratio (Hav × 100 / D) of 60% was attached to the produced hollow fiber membrane module, and the following confirmation test was performed. The filtration operation was performed at a rate of 5 m / day for 60 minutes, followed by a step of back-pressure washing for 60 seconds, and this step was repeated. And as a result of removing the cap from the hollow fiber membrane module and counting the number of sludge blockage at the end surface opening of the hollow fiber membrane, the number of sludge blockage at the end opening of the hollow fiber membrane was 2 in one month continuous operation. .

Comparative Example 1
A hollow fiber membrane bundle comprising 22320 hollow fiber membranes having an inner diameter of 0.8 mm, an outer diameter of 1.3 mm, a length of 1230 mm, and a cellulose acetate resin was inserted into the case housing. Then, it was adhesively sealed with a urethane-based adhesive by a centrifugal sealing machine (manufactured by Toho Machine Industry Co., Ltd., horizontal centrifugal molding machine).

  A cap as shown in FIG. 2 having (Hav / D) × 100 of 30% was attached to the produced hollow fiber membrane module, and the following confirmation test was performed. The filtration operation was performed at a rate of 5 m / day for 60 minutes, followed by a step of back-pressure washing for 60 seconds, and this step was repeated. And as a result of counting the sludge blockage number of the end surface opening part of a hollow fiber membrane similarly, the sludge blockage number of the end part opening of a hollow fiber membrane was 400 pieces by continuous operation for one month.

The longitudinal cross-sectional view of the hollow fiber membrane module of this invention. The longitudinal cross-sectional view of the conventional hollow fiber membrane module.

Explanation of symbols

10 hollow fiber membrane module 11 cap 20 case housing 30 hollow fiber membrane bundle

Claims (3)

A hollow fiber membrane module having a case housing and a cap connected to an opening end face of at least one end of the case housing; and a hollow fiber membrane bundle accommodated in the case housing;
The cap has a bottom surface having a liquid inlet / outlet and a side surface integrated with the bottom surface, and the side facing the liquid inlet / outlet is opened,
A hollow fiber having a ratio (Hav × 100 / D) of a diameter (D) of the case housing and a rising average height (Hav) of a portion excluding the liquid inlet / outlet on the inner surface of the cap in a range of 35% to 70%. Membrane module.   The hollow fiber membrane module according to claim 1, wherein the bottom surface of the cap and the end surface opening of the bundle of hollow fiber membranes accommodated in the case housing face each other, and the bottom surface is a flat surface or a curved surface similar thereto. The hollow fiber membrane module according to claim 1 or 2, wherein the case housing has a diameter of 200 mm or more and has at least one fluid inlet / outlet at a side portion.