JPH09117645A - Flat membrane element of dipping type membrane separation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase mechanical strength, in width, of a flat membrane element of a dipping type membrane separation device in which the surface of a supporting plate is covered with a flat membrane thereby to prevent the element from being deformed into an arcuate shape in width direction even after extended use by fitting a reinforcing material along either or both of upper and lower sides of the supporting plate. SOLUTION: In a flat membrane element, a fluid path spacer 12 made of nonwoven fabric and a flat membrane 13 such as MF membrane or the like outside the spacer 12 are superposed on the front and rear surfaces 11a, 11b of a vertically erected supporting plate 11 formed from ABS resin, and a peripheral edge 13' of the membrane 13 is fixedly attached to the surfaces 11a, 11b and the spacer 12 is covered with the membrane 13. And a fluid path space 14 for water passed through the membrane 13 is formed from the membrane 13 and the spacer 12 on the surfaces 11a, 11b, and left and right water intake pipes 15 are erected on the top surface of the plate 11. In that case, a reinforcing material 18 is attached to the upper side of the plate 11 between the pipes 15, 15 and to the lower side thereof along a neary entire length, thereby to reinforce the plate 11 in its width direction to prevent the plate 11 from being deformed into an arcuate shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an immersion type for collecting permeated water that has permeated a flat membrane while diffusing from below under water in a treatment tank while vertically arranging them in the front-rear direction at intervals. The present invention relates to a flat membrane element of a membrane separation device.

[0002]

2. Description of the Related Art FIG. 2 shows a biological reaction tank to which raw water is supplied,
An air lift cylinder 2 is erected in the water of a treatment tank 1 such as a membrane immersion tank, and a plurality of flat membrane elements 3 are arranged in a row in the upper half of the air lift cylinder at a predetermined interval 5 in a row to form a module. An air diffuser 4 for ejecting air from the blower is arranged below the inside of the air lift cylinder. When air is diffused from the air diffuser 4 and the pump P is operated, a crossflow upward flow is generated by an air lift in the space 5 in the front-back direction of the flat sheet membrane element, and a cake or gel-like substance adheres to the membrane surface of the flat sheet membrane element. While preventing the permeated water, the permeated water in the raw water permeates the flat membrane by the suction action of the pump and flows into the inside of the element, and the permeated water is collected through the header pipe 7 connected to the water collecting pipe 6 of each element and the pump P. Can be watered.

A flat membrane element is arranged at regular intervals 5 in the front-back direction.
In order to maintain the above, and to modularize the air lift cylinder 2, as shown in FIG. 3, spacing members 8 are provided at opposite sides of the air lift cylinder 2 at regular intervals, and both side edges of the flat sheet membrane element are arranged at the front and rear spacing members. It is designed to be inserted from above between.

[0004]

The support plate of a flat sheet membrane element having flat sheet membranes attached to both front and rear surfaces is made of ABS resin or PVC.
It is a rectangular flat plate with a height of about 1 m, a width of about 50 cm, and a thickness of about 6 mm molded from resin, etc., and is distorted due to secular change due to long-term use and vibration in the air lift flow due to bubbles ejected from the diffuser pipe. , Bow-shaped warpage occurs in the lateral width of the support plate. Then, as shown by X in FIG. 3, there is a narrow path between the front and rear flat sheet membrane elements that cannot maintain the predetermined interval 5, and the crossflow upward flow due to the air lift cannot rise in the narrow path, so that the interval 5 is set. Uneven flow occurs, and a cake or gel-like substance adheres to the film surface of the bottleneck to clog the film or block the bottleneck, resulting in a decrease in flux. The flat membrane element thus deformed or the membrane is clogged needs to be replaced with a new flat membrane element, which increases maintenance costs.

[0005]

DISCLOSURE OF THE INVENTION The present invention is to solve the above-mentioned problems, and in a flat membrane element of an immersion type membrane separation device in which the plate surface of the support plate is covered with a flat membrane, A reinforcing material is provided on one or both of the upper side and the lower side along the side.

[0006]

1 shows an embodiment of a flat sheet membrane element according to the present invention. 11 is an ABS that stands vertically
A support plate made of resin or PVC resin, on the front and rear vertical plate surfaces 11a and 11b, a flow path spacer 12 such as a non-woven fabric, and a flat film 13 such as an MF film or a UF film on the outside.
The flat film peripheral edge portion 13 ′ is fixed to the plate surfaces 11 a and 11 b so that the flat film 13 surrounds and covers the flow path spacer 12, and the flat film and the flow path spacer allow the flat film to permeate the plate surfaces 11 a and 11 b. A flow passage space 14 for the permeated water is formed. Then, on the upper surface of the support plate, left and right 2 communicating with the circulation space 14 of the permeated water.
A water sampling pipe 15 for books is erected. In order to connect each water sampling pipe 15 to the permeated water flow space 14, the support plate 11 has lateral grooves 16 in the left-right direction at the upper portions of the front and rear plate surfaces 11a and 11b.
The left and right ends of the lateral groove are provided with through holes 17 that open to the front and rear plate surfaces 11a and 11b, and the left water sampling pipe 5 is connected to the left through hole 17.
In addition, the right water sampling pipe 15 is inserted into the right through hole 17 from the upper surface of the support plate.

[0007] A plurality of the flat sheet membrane elements are vertically arranged in water in a treatment tank to which raw water is supplied with an interval in the front-rear direction, and the right and left water collecting pipes 15, 15 of each flat sheet membrane element are arranged.
When the suction header 6 connected to the suction pump is connected to the suction pump, and the suction pump is operated while diffusing from below, as described above, the flow spaces 14 on the front and rear plate surfaces of each flat sheet membrane element become negative pressure and negative pressure. The permeated water which has permeated the flat membrane in the raw water by the suction action of pressure flows toward the lateral groove 16 in the circulation space as shown in FIG. 2, and from the lateral groove 16 the left and right through holes 17, 17 and the left and right water sampling pipes 15 , 15, the suction header, and the suction pump to collect water.

In order to reinforce the lateral width of the support plate 11 so that bow-shaped warpage does not occur, a reinforcing material 18 is provided in the section between the water sampling pipes 15 on the upper side of the support plate and the substantially entire length of the lower side. It is installed.

The reinforcing member of the illustrated embodiment is a groove-shaped cross-section member made of a steel plate having a thickness of about 1 mm. Install by sandwiching. In this case, when the cross-sectional shape of the upper side or the lower side of the support plate into which the groove-shaped cross-section material is fitted is made into a dovetail shape as shown in the drawing, and both side pieces of the groove-shaped cross-section material are sandwiched along both slopes of the dovetail shape. The attachment strength of the groove-shaped cross-section material is greatly increased, and the groove-shaped cross-section material does not come off from the support plate.

The reinforcing material is not limited to the groove-shaped cross-section material, but a steel rod having a diameter of about 3 mm may be embedded as the reinforcing material in the upper side and the lower side of the support plate. This steel rod is used for forming the support plate when the water sampling pipe 15 is used.
The steel rod is mounted by locating it in the cavity of the mold of the support plate so as to be located in the section between 15 and 15 and the inside of the lower side, and molding the support plate by insert molding so that this steel rod is embedded. be able to.

Further, a shallow groove or hole through which a steel rod can be inserted is formed on the lower side of the support plate as a similar reinforcing material, and after the support plate is formed, the steel rod is passed through the groove or hole and then bonded. You may fix it.

The reinforcing member 18 may be attached to both the lower side and the section between the water sampling pipes 15 on the upper side of the support plate, or may be attached only to the upper side or the lower side of the support plate.

Further, the reinforcing member is a groove-shaped cross-section material of a steel plate or a steel rod, but it is not limited to this, and any material can be used as long as it can prevent distortion of the support plate in terms of strength.

[0014]

As is apparent from the above, the flat sheet membrane element of the present invention has the reinforcing member 18 along the upper side or the lower side of the support plate.
Since the mechanical strength of the width is increased by attaching the, the width does not warp like an arc even after long-term use. Therefore, during operation, there is no bottleneck in the adjacent space before and after the flat sheet membrane element, the space is not blocked, and the flux is not lowered.

[Brief description of the drawings]

FIG. 1A is a partially cutaway front view of an embodiment of a flat sheet membrane element of the present invention, FIG. 1B is a cross-sectional view taken along line AB of FIG. It is sectional drawing in the D line.

FIG. 2 is a cross-sectional view of an immersion type membrane separation device.

3 is a plan view of the tubular frame and flat sheet membrane element of FIG. 2. FIG.

[Explanation of symbols]

 1 Treatment Tank 2 Air Lift Cylinder 3 Flat Membrane Element 4 Diffuser Tube 5 Front-to-Back Spacing of Flat Membrane Element 6 Water Pipe 7 Suction Header 11 Flat Membrane Element Support Plate 12 Spacer 13 Flat Membrane 14 Permeate Flow Space 15 Water Pipe 16 Lateral groove of support plate 17 Through hole of support plate 18 Reinforcing member

Claims (1)

[Claims] 1. In a flat sheet membrane element of an immersion type membrane separation device in which a plate surface of a support plate is covered with a flat sheet, a reinforcing material is provided along one side or both of the upper side and the lower side of the support plate. A flat membrane element for a submerged membrane separation device, characterized by: