KR20070000566A - Water purifier module of hollow fiber membrane with air-vent function - Google Patents

Abstract

A hollow fiber membrane module for a water purifier, which can improve a fluid flowing and passing amount greatly within the module by maintaining an air-vent function, is provided. In a hollow fiber membrane module for a water purifier, comprising hydrophilic hollow fiber membranes(1), a hollow fiber membrane module for the water purifier with an air-vent function is characterized in that a hydrophobic hollow fiber membrane(2) is added into the module. The hydrophobic hollow fiber membrane is formed of polyethylene. The hydrophobic hollow fiber membrane has pores which are formed therein and have an average diameter of 0.1 to 0.5 mum. The hydrophobic hollow fiber membrane has an entire area corresponding to 0.1 to 2.0% of an entire area of the hydrophilic hollow fiber membranes. The hydrophilic hollow fiber membranes are formed of a resin selected from polysulfone resin, polyether sulfone resin and sulfonated polysulfone resin.

Description

Hollow fiber membrane module for water purifier with degassing function {Water purifier module of hollow fiber membrane with air-vent function}

1 is a cross-sectional view of the present invention.

2 is a scanning electron micrograph of the outer surface of the hydrophobic hollow fiber membrane (high density polyethylene hollow fiber membrane) used in the present invention.

3 is a scanning electron microscope photograph of the inner surface of a hydrophobic hollow fiber membrane (high density polyethylene hollow fiber membrane) used in the present invention.

* Description of symbols on the main parts of the drawings

1: hydrophilic hollow fiber membrane 2: hydrophobic hollow fiber membrane

3: Non-woven Fabric for Hollow Fiber Membrane Bundle Protection

4: adhesive polyurethane resin

The present invention relates to a water purifier module which is a household water treatment apparatus for obtaining drinking water used as drinking water, and more particularly, to a hollow fiber membrane module for water purifier, in which a degassing function is imposed to improve fluid flow and water flow rate inside the module. It is about.

As the industry develops, various pollutants increase rapidly, and water quality problems for drinking water used for drinking water are seriously raised. In particular, domestic tap water is seriously contaminated by various bacteria, iron, rust and organic matter.

The reason for this is that as the water supply pipes supplied from the purified water to each household age, organic matter invades, and various microorganisms such as E. coli, cholera, typhoid fever and dysentery, bacteria and bacteria exist in the water storage tank.

If household tap water is contaminated, it is harmful to the human body and causes unpleasant feelings when drinking by smell and taste caused by pollutants.

Recently, in order to efficiently remove various contaminants in the drinking water, a hollow fiber membrane module including a combination of an adsorption filter material such as ion exchange resin, activated carbon or silver activated carbon, and a hollow fiber membrane for separation in water is widely used.

The hollow fiber membrane module includes a body including a feed liquid inlet, a filtrate outlet, and a filtrate outlet, and a hollow fiber membrane formed inside the body, wherein the hollow fiber membrane is embedded in the body and one end of the upper portion of the hollow fiber membrane module. The cap has a structure fixed to one end with an adhesive.

The use of the separation membrane is very wide, and is manufactured and used in various forms. One of them is the hollow fiber membrane module made of hollow fiber in the form of hollow fiber has a large permeate flow rate in a small module has been widely used in each field.

The hollow fiber membrane module is made of two types, the first of which is 300-2,000mm in length, outer diameter of 0.1-2mm hollow fiber hundreds to tens of thousands of strands inserted into the tube container constituting the body and fixed to both ends by the spacer Potted with adhesives such as urethane, epoxy, etc., both sides are fixed with adhesive, so the backwashing method is used to physically desorb contaminants attached to the surface using water in the transmission direction opposite to the supply direction. Is an I-shaped module. Second, the U-shaped module is manufactured by inserting the hollow fiber membranes into a U-shape and inserting the tube into a tube container.

The backwashing method using the I-shaped module among the above modules has a short-term effect, but the effect is halved in the long-term use, and it is easy to cause the microstructure of the membrane to be periodically changed and the hollow fiber membrane is cut off, so the U-shaped module is mainly used. Since the U-shaped module does not port one side, there is an advantage of a cost reduction effect due to a decrease in the use of adhesive and a reduction in defect rate and process shortening that may occur when porting.

The conventional hollow fiber membranes constituting the I-shaped and U-shaped hollow fiber membrane modules are made of hydrophilic resins such as polysulfone resins and the like, and have hydrophilicity, thereby degrading their own air-venting function.

As a result, when the fluid to be filtered (water tap water) is first introduced into the conventional hollow fiber membrane module, the air stays inside the module before the air inside the module is discharged through the hydrophilic hollow fiber membrane. As the volume occupied in the module decreases the flow rate introduced into the module, a problem arises in that the amount of water flow decreases.

An object of the present invention is to provide a hollow fiber membrane module for a water purifier that can improve the fluid flow and water flow in the module with a degassing function in order to solve the problems of the conventional hollow fiber membrane modules for water purifier as described above.

The present invention is to provide a degassing (Air-Vent) function that allows the air inside the module to be quickly discharged out of the module without staying inside the module when the fluid to be filtered is first introduced into the hollow fiber membrane module.

The present invention is to provide a degassing function to the hollow fiber membrane module to facilitate the flow of fluid in the module, and to prevent a decrease in water flow rate, which is the most important performance of the hollow fiber membrane module.

The hollow fiber membrane module for water purifier of the present invention for achieving such a problem is characterized in that the hydrophobic hollow fiber membrane 2 is incorporated into the hollow fiber membrane module for water purifier composed of the hydrophilic hollow fiber membranes 1.

Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

First, the present invention is characterized in that the hydrophobic hollow fiber membrane 2 is mixed in a hollow fiber membrane module for water purifiers composed of hydrophilic hollow fiber membranes 1 as shown in FIG.

1 is a cross-sectional view showing an example of the hollow fiber membrane module for water purifier of the present invention.

1 shows a U-shaped hydrophilic hollow fiber membrane 1 in which only one hem portion is fixed by an adhesive resin 4, U-shaped hydrophobic hollow fiber membrane 2 incorporated therebetween, and these hollow fiber membrane bundles. It consists of a nonwoven fabric (3) for protection.

As described above, in the present invention, when the fluid is introduced into the module by incorporating the hydrophobic hollow fiber membrane 2 into the hydrophilic hollow fiber membrane 1, the air inside the module is easily moved out of the module through the hydrophobic hollow fiber membrane 2. To be discharged, that is, characterized in that to give a degassing (Air-Vent) function.

The hydrophilic hollow fiber membrane 2 and the hydrophobic hollow fiber membrane 1 may both be I-shaped or U-shaped. The hydrophobic hollow fiber membrane 2 is made of a polyethylene resin, it is preferable that the average diameter of the pores (pore) formed therein is 0.1 ~ 0.5um.

The pore average diameter and porosity of the hydrophobic hollow fiber membrane 2 can be controlled by the conditions of the melt spinning and stretching process for producing the hydrophobic hollow fiber membrane 2.

The total area of the hydrophobic hollow fiber membrane 2 is preferably 0.1% to 2.0% of the total area of the hydrophilic hollow fiber membrane 1 to improve the degassing function.

The hydrophilic hollow fiber membrane 1 is made of a hydrophilic resin such as polysulfone resin, polyethersulfone resin, sulfonated polysulfone resin and the like.

The present invention is the difference between the fluid inlet pressure (P ₁ ) of the module and the fluid outlet pressure (P2) of the module when the water is immersed in the module for 1 day and passed through 15Kpa pressure (△ P = P ₁ -P ₂ ) It takes less than 7 seconds to get 1.6Kpa or less.

In the present invention, the time required for the above pressure difference (ΔP) to be 1.6 Kpa or less was evaluated based on the degassing function.

Hereinafter, the present invention will be described in more detail with reference to Examples and Comparative Examples. However, the present invention is not limited only to the following examples.

Example 1

When a U-shaped hollow fiber membrane module is manufactured by a conventional method using a polysulfone hollow fiber membrane (hydrophilic hollow fiber membrane), a polyethylene hollow fiber membrane (hydrophobic hollow fiber membrane) having an average diameter of 0.4 mu m in the module is prepared by The hollow fiber membrane module was manufactured by mixing at an area ratio of 0.6% of the total area.

The results of evaluating the water flow rate and degassing function of the hollow fiber membrane module manufactured as described above are shown in Table 2.

Examples 2-4

A hollow fiber membrane module was prepared in the same manner as in Example 1 except that the area ratio of the polyethylene hollow fiber membrane to the total area of the polysulfone hollow fiber membrane and the pore average diameter of the polyethylene hollow fiber membrane were changed as shown in Table 1.

The results of evaluating the total quantity and degassing function of the hollow fiber membrane module thus prepared are shown in Table 2.

 Manufacture conditions division Area ratio of polyethylene hollow fiber membrane (%) Pore average diameter of polyethylene hollow fiber membrane (㎛) Example 1 0.6 0.4 Example 2 1.0 0.3 Example 3 0.8 0.2 Example 4 0.4 0.4

Comparative Example 1

The U-shaped hollow fiber membrane module was manufactured in a conventional manner using only polysulfone hollow fiber membranes (hydrophilic hollow fiber membranes) without mixing polyethylene hollow fiber membranes (hydrophobic hollow fiber membranes).

The results of evaluating the water flow rate and degassing function of the hollow fiber membrane module manufactured as described above are shown in Table 2.

Hollow fiber membrane module performance evaluation result division Water flow rate [Instant flow rate when the cumulative water flow time is 3,000 hours (mg / min)] Degassing function [time (seconds) for △ P to be 1.6Kpa or less] Example 1 3.2 1.33 Example 2 3.4 0.54 Example 3 3.3 1.13 Example 4 2.8 5.13 Comparative Example 1 1.4 △ P not more than 1.6Kpa even more than 60 seconds

The hollow fiber membrane module for a water purifier of the present invention has an excellent degassing function, so that the fluid flow inside the module is smooth and the amount of water flowing through the module is greatly improved.

Claims (6)

A hollow fiber membrane module for water purifiers comprising hydrophilic hollow fiber membranes (1), wherein a hydrophobic hollow fiber membrane (2) is incorporated in the module. The hollow fiber membrane module for water purifier with a deaeration function according to claim 1, characterized in that the hydrophobic hollow fiber membrane (2) is made of polyethylene. The hollow fiber membrane module for water purifier with a deaeration function according to claim 1, characterized in that the average diameter of pores present in the hydrophobic hollow fiber membrane (2) is 0.1 to 0.5 µm. The hollow fiber membrane module for a water purifier according to claim 1, wherein the total area of the hydrophobic hollow fiber membrane (2) is 0.1 to 2.0% of the total area of the hydrophilic hollow fiber membrane (1). The difference between the fluid inlet pressure (P ₁ ) of the module and the fluid outlet pressure (P2) of the module (ΔP = P ₁ −) when water is immersed in the module for 1 day and then passed through at a pressure of 15 Kpa. Water purifier module with a degassing function, characterized in that the time required for P ₂ ) to be 1.6Kpa or less within 7 seconds. The water purifier module with a degassing function according to claim 1, wherein the hydrophilic hollow fiber membrane (1) is made of one resin selected from polysulfone resin, polyethersulfone resin, and sulfonated polysulfone resin.

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