JPH11333263A - Membrane element and membrane separation device using the element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To manufacture membrane elements suitable for increasing the filtration capacity and provide a membrane separation device thereof. SOLUTION: In a membrane separation device, two flat plates 11 and 12 disposed almost in parallel with and at an interval are integrated with a plurality of partitions 13 provided between the flat plates 11 and 12, and hollow sections 2 are formed between the flat plates 11 and 12 and the partitions 13. Membranes 3, on which faces on one side as membrane materials 31 and faces on the other side as substrates 30 are integrated together, formed on both faces of a filter plate 1 with holes 14 formed on the flat plates 11 and 12 and communicated with the hollow sections 2 are provided with a plurality of membrane elements with substrates 30 positioned on the side of the filter plate 1, and both sides of respective membrane elements are integrated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a membrane element and a membrane separation apparatus using the same, and more particularly, to a membrane element suitable for increasing a filtration capacity and a membrane separation apparatus using the same. .

[0002]

2. Description of the Related Art A membrane separation apparatus for filtering or concentrating industrial wastewater or middle sewage water, etc., often employs a method of filtering a stock solution by applying a negative pressure to a filtrate side of a plurality of membrane elements immersed in a stock solution tank. ing.

[0003] In the above-mentioned membrane separation device, as the filtration proceeds, the substance trapped by the filtration membrane adheres to the surface of the filtration membrane to form a cake layer, thereby decreasing the filtration flow rate. Alternatively, the filtration is interrupted periodically and air is supplied from below the membrane element to generate air bubbles, and the adhesion of the cake layer is suppressed or caused by the vibration of the filtration membrane due to the air bubbles and the contact between the air bubbles and the cake layer. The peeling of the cake layer is promoted, so that the membrane element can be used for a long time.

As the membrane element used in the above-mentioned membrane separation device, there are a membrane element made of a hollow fiber and a flat membrane suitable for filtration of a relatively large volume. In recent years, a membrane element made of a flat membrane has been frequently used. ing.

[0005] The flat membrane is obtained by coating a membrane material on a support such as a non-woven fabric in order to increase the strength. A membrane element using such a flat membrane has the flat membrane on both sides of a filter plate. And a filtrate is obtained from a filtrate collecting channel formed in the filter plate.

As an example of a membrane element using the above-mentioned flat membrane, there is one described in JP-A-8-10587.

That is, what is described in the above publication is
A plurality of barriers are arranged at a predetermined interval between two flat plates which are arranged substantially in parallel at an interval to integrate the two flat plates and the barrier, and a permeated water chamber surrounded by both flat plates and the barrier Is a membrane element in which a permeated water collecting hole is opened in an opposing flat plate located between the barriers to constitute a support plate, and a membrane is stretched on the outer surface of the flat plate of the support plate. By stretching the membrane, the structure can be simplified, and the vibration of the support plate can be prevented even against a strong bubble flow, so that a highly durable membrane element can be obtained. The film is stretched on the support plate by bonding or welding the periphery of the film to the support plate. If necessary, the strength of the film can be increased by using a linear or cross-shaped fastening portion. It is also possible to raise it.

[0008]

In the membrane element described in the above publication, consideration has been given to the prevention of vibration of the support plate due to the bubble flow, but the membrane is directly stretched on the support plate. When the area is large, even if a linear or cross-shaped fastening part is used, the membrane peels off from the support plate during long-term use due to the swinging of the membrane surface when it receives a strong bubble flow. It may be damaged and the undiluted solution may be mixed into the permeate.
When a membrane element having a large membrane area is formed, there is a problem that its reliability is reduced. As a method of solving such a problem, it is conceivable to increase the number of linear or cross-shaped fastening portions, but the number of steps for providing a large number of fastening portions increases, which is not practical. .

[0009]

According to a first aspect of the present invention, a filter plate comprises two flat plates arranged substantially in parallel at intervals and a plurality of filter plates provided between the flat plates. Integrating the partition wall, forming a hollow portion between the flat plate and the partition wall and providing a hole communicating with the hollow portion in the flat plate, a membrane element having a membrane on both sides of the filter plate. The film body is integrated such that one surface is a film material and the other surface is a support, and the support of the film is opposed to a filter plate and partially formed on the filter plate. Or, the whole surface is bound, and the hollow portion is used as a filtrate collecting channel, whereby the support on the other surface of the membrane and the filter plate can be firmly bound. Therefore, even if a membrane element with a large membrane area is configured, a decrease in reliability can be prevented. .

A second aspect of the present invention is a membrane separation device comprising a plurality of the membrane elements according to the first aspect, wherein both sides of each of the membrane elements are integrated, thereby increasing the filtration capacity. Thus, it is possible to obtain a membrane separation device that can be used.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described based on its embodiments.

FIG. 1 is a sectional view of a membrane element according to an embodiment of the present invention.

The feature of the membrane element according to the embodiment of the present invention shown in FIG. 1 is that the filter plate 1 is composed of two flat plates 11 and 12 which are arranged in parallel with a space therebetween and the flat plates 11 and 12.
A plurality of partition walls 13 provided therebetween are integrated with each other,
A hollow portion 2 is formed between the first and second partition walls 13 and 13 and the flat plates 11 and 12 are provided with a hole 14 communicating with the hollow portion 2. And the other surface is integrated so as to be the support 30, and the support 30 of the membrane 3 is provided on both sides of the filter plate 1.
Are arranged facing each other, the support 30 is partially or entirely bound to the filter plate 1, and the hollow portion 2 is a filtrate collecting channel.

The filter plate 1 is preferably made of a lightweight and inexpensive resin such as polypropylene, polyethylene and polycarbonate which can be continuously manufactured by extrusion.

The film body 3 has a basis weight of 50 to 100.
g / m ² , and a support 30 having a thickness of about 0.2 to 0.4 mm
A polyolefin-based or polysulfone-based membrane material 31 is coated on one surface of a non-woven fabric such as a polyolefin-based or polyester-based material, or the membrane material 31 is formed by laminating the membrane material 31 on the support 30.
Has a hole diameter of about 0.25 to 0.4 μm and a thickness of 0.1
０．２0.2 mm.

Then, on the surface of the support 30 of the film body 3,
3 to 30 g / m ^{2 of} low melting point polyethylene powder is dispersed,
The filter plate 1 is brought into contact with the filter plate 1 and heat-treated at a temperature higher than the melting point of the low-melting polyethylene and lower than the melting point of the film material 31 of the film body 3, and then cooled to be integrated.

Alternatively, a hot melt resin may be disposed on the filter plate 1 and the surface of the support 30 of the membrane 3 may be disposed thereon to melt the hot melt resin and integrate the same.

A plurality of the membrane elements are juxtaposed at an appropriate interval, and both sides of each membrane element are
When integrated with a resin that cures over time such as an epoxy resin or a polyurethane resin or a thermosetting resin, a membrane separation device having a large filtration capacity can be obtained.

[0019]

As described above, according to the first aspect of the present invention, since the filter plate and the membrane can be firmly bound, the durability of the membrane element having a large membrane area can be improved. According to the second aspect of the present invention, it is possible to contribute to improvement of the reliability of a membrane separation device having a large filtration capacity. is there.

[Brief description of the drawings]

FIG. 1 is a sectional view of a membrane element according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Filter plate 2 Hollow part 3 Membrane

Claims (2)

[Claims] 1. A filter plate is formed by integrating two flat plates arranged substantially in parallel at an interval and a plurality of partition walls provided between the flat plates, and forming a hollow portion between the flat plate and the partition walls. And a membrane element in which a membrane is provided on both sides of the filter plate, wherein the membrane has a membrane material on one surface and a membrane material on the other surface. Are integrated so as to be a support, characterized in that the support of the membrane body is bonded to the filter plate in part or in whole so as to face the filter plate, and the hollow portion is a filtrate collecting channel. Membrane element. 2. A membrane separation device comprising a plurality of the membrane elements according to claim 1, wherein both sides of each of the membrane elements are integrated.