JPH0871382A - Membrane device of immersion type membrane separator - Google Patents

Abstract

PURPOSE: To individually take out an arbitrary flat membrane element from a membrane unit while laterally tensioning a large number of flat membrane elements constituting the membrane unit and arranged and stacked in one row in a laminated state. CONSTITUTION: A pair of thick-walled side pillars 30 are provided along both side parts of a flat membrane element 11 having openings 15 and the support pieces 32 provided to the upper and lower end parts of the side pillars and communicating with the openings of the flat membrane element are applied to the flat membrane element and the seal caps 40 sealing the openings of the flat membrane element are fixed to the cavities of the support pieces in a detachable manner. A large number of membrane units each formed by attaching the flat membrane element 11 to a pair of the side pillars 30 are stacked in one row in a laminated state by a plurality of support rod members 52 and force is applied to the paired side pillars of each of the membrane units in a direction mutually separating the side pillars to tension each of the flat membrane elements.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a large number of flat membrane elements having flat membranes such as reverse osmosis membranes, ultrafiltration membranes, microfiltration membranes, other polymer membranes and inorganic (alumina ceramic etc.) membranes. The present invention relates to a membrane unit of an immersion-type membrane separation device that performs membrane separation by immersing in a liquid in a dipping tank.

[0002]

2. Description of the Related Art Immersion type membrane separators can obtain permeated water by performing membrane separation with low energy by a water head difference based on the water depth in the immersion tank in which the membrane unit is immersed and the suction force of a suction pump. 6 to 8 show that the applicant of the present invention is Japanese Patent Application No. 5-263.
146 shows the immersion type membrane separation device proposed in No. 146, and the flat sheet membrane element 11 addressed to one of them is a flat and square tricot spacer composed of a tricot knitted fabric, a net spacer,
Flat membranes 13, 13 of the same size are superposed on both surfaces of a water-permeable channel spacer 12 such as a perforated plate spacer, and four peripheral edges thereof are sealed 14 by heat, adhesive bonding, high-frequency welding or the like to be integrally formed. A permeation chamber 11 ′ surrounded by a seal 14 is formed between the flat membranes 13 and 13. Each flat membrane element is provided with water collecting ports 15 and 15 at two corners in a diagonal direction inside which are surrounded by a seal 14. Reference numeral 16 denotes an elastic gasket which is arranged at a corner having the water collecting port 15 of the flat sheet membrane element and maintains a predetermined water passage interval 18 between two adjacent flat sheet membrane elements, and is a right angle corresponding to the corner of the flat sheet membrane element. It is a triangle or a quadrangle having two sides and has an opening 17 of the same size that communicates with the water collection port 15. Reference numerals 19 and 20 denote end plates before and after sandwiching a row of a large number of flat sheet membrane elements facing each other in a laminated state with a gasket 16 keeping a water passage distance therebetween, and having the same size as the membrane element. . Through holes 21 communicating with the water collecting ports 15 and 15 of the flat sheet membrane element are formed in each end plate at the same two corners. The through holes of the end plates 19 and 20 have a large diameter portion 22 having the same size as the water collecting port 15 of the flat sheet membrane element and the opening 17 of the gasket 16, and the remaining portion is a small diameter portion 24 through which the tightening bolt 25 passes.
It has become. Further, a connection port 23 opened to the outer surface is provided at the back of the large diameter portion 22.

In order to assemble the membrane unit, a predetermined number of flat membrane elements 11 are lined up in a row through a gasket 16 (the water collecting port 15 of the flat membrane element and the opening 17 of the gasket are communicated) and are communicated. Bolts 25 are passed through the water collecting ports 15 of all the flat sheet membrane elements and the openings 17 of all the gaskets in series, and through holes 21 are fitted to the respective end portions of the bolts 25, and the flat sheet membrane elements are provided at the front and rear end plates 19 and 20. 1
1, the gasket 16 is sandwiched, and the nuts 26 screwed into the respective ends of the bolt are tightened to the end plates 19 and 20, and the flat membrane element and the gasket are sandwiched to be integrated. An O-ring 27 is fitted to a portion of each end of the bolt 25 located inside the small diameter portion 23 of the through hole for sealing. As a result, the large diameter portion 22 of the through hole of the end plate and the opening 17 of the gasket
And the water passage holes 15 of the membrane element are connected in series, and two water passages 28 and 29 are formed to connect the permeation chambers 11 ′ of the individual flat sheet membrane elements.

In FIG. 8, the flat membrane element assembly (membrane unit) is immersed in the liquid in the dipping tank 1 so that one of the water channels is on the top and the other is on the bottom to form an immersion type membrane separator. A flow sheet of one example is shown in which the suction pump P1 is attached to one of the connection ports 23 in the end plates 19 and 20 of the upper water channel 28.
Is connected to the permeated water extraction pipe 2, and the other connection port is closed with a plug. The take-out pipe is branched into two downstream of the suction pump, one of the branch pipes 2a rises, and the water surface is the same as that of the immersion tank 1 or opens from above into a permeated water storage tank 3 which is higher than the immersion tank 1. The other 2b extends straight and opens to the drainage tank 4. The branch pipes 2a and 2b are provided with on-off valves V1 and V2 on the way. End plate 1 of the waterway 29 below the membrane unit
The replacement water supply pipe 5 protruding from above into the liquid in the storage tank 3 is connected to one of the connection ports 23 at the ports 9 and 20, and the other connection port 23 is closed with a plug. Then, a chemical injection pipe 7 for injecting the chemical liquid in the chemical liquid tank 6 with a pump P2 is connected in the middle of the supply pipe 5. In addition, in the supply pipe 5, a water channel 29 is provided rather than a connection point of the chemical injection pipe
An on-off valve V3 is installed on the side, and the immersion tank 1 is provided with a raw water supply pipe.
A sludge discharge pipe 8 is provided at the bottom. Open / close valve V for collecting permeate
1 is opened, V2 and V3 are closed, and the suction pump P1 is operated. As a result, due to the suction force of the pump and the water head difference, the liquid in the immersion tank permeates the flat membrane 13 from the water passage interval 18 between the flat membrane elements, flows in the permeation chamber 11 ′, and reaches the water collecting port 15. It flows in and enters the storage tank 3 through the water channel 28 and the pipes 2 and 2a. The permeated water is collected, and when a certain amount of cake adheres to the outer surface of the membrane, the on-off valve V1 is closed, V2 and V3 are opened, and the suction pump P1 and the chemical solution pump P2 are operated to perform cleaning. . As a result, the permeated water filling the permeation chamber of the membrane unit is drawn by the suction pump, flows through the water channel 28, the pipes 2 and 2b and enters the drainage tank 4, and at the same time, the permeated water in the storage tank 3 becomes By the water head difference and the suction of the suction pump, the replacement water flows through the supply pipe 5 toward the membrane unit, merges with the chemical liquid injected by the chemical injection pipe 7, and becomes a cleaning liquid of a predetermined concentration, and passes through a series of water channels 29. It enters the permeate chamber without applying excessive pressure to the membrane. In this way, when the cleaning liquid is replaced with the permeated water in the permeation chamber, the suction pump P1 and the chemical liquid pump P2 are stopped, V2 is closed in addition to the on-off valve V1, and the storage tank 3 and the immersion tank 1 are closed.
The cleaning liquid is sent to the permeation chamber by the water head difference between and, and the cleaning liquid in the permeation chamber is permeated from the inner surface to the outer surface of the membrane, and the cake adhering to the outer surface is peeled off. Since the cleaning liquid permeates the membrane in the direction opposite to the permeated water, the cake easily peels off from the outer surface of the membrane and is removed. The removed cake is discharged from the dipping tank by opening the valve of the mud discharge pipe 8. After cleaning, close the open / close valve V1, V2, V
3 is opened, the suction pump P1 is operated, and the cleaning liquid in the permeation chamber is sucked into the drainage tank 4, and at the same time, the permeated water in the storage tank is sucked by the suction pump and the supply pipe 5 by the water head difference between the storage tank and the immersion tank.
To the permeate chamber, and the permeate replaces the cleaning liquid in the permeate chamber. After the permeate chamber is replaced with permeate, the on-off valve V1 is opened, V2 and V3 are closed, and the permeate water sampling process is restarted.

[0005]

In the membrane unit of the above-mentioned prior art device, a gasket is interposed between one of a number of flat membrane elements, and end plates are applied to the front and rear, and a series of bolts are connected to the flat membrane element. Since the gasket and the front and rear end plates are pierced and the nuts are tightened and sandwiched between the front and rear end plates, it is necessary to adjust the pulling degree of each membrane element. There was a limit to stacking, and it was difficult to increase the size of the membrane unit. An object of the present invention is to provide a membrane unit in which one membrane can be easily attached and detached and which can be fixed in a tensioned state with a simple structure.

[0006]

The present invention was developed in order to solve the above-mentioned problems, and a pair of thick side columns are provided along both sides of a flat sheet membrane element having an opening,
Supporting pieces provided at the upper and lower ends of the side pillars and contacting the flat sheet membrane element with supporting pieces communicating with the openings of the flat sheet membrane element,
A plurality of support rods in which a plurality of membrane units having the flat membrane elements attached to one pair of side columns are horizontally arranged, with a seal cap for closing the opening of the flat membrane element being detachably fixed to the support piece. It is characterized in that the members are arranged in a stacked state in a single row and the flat membrane elements are tensioned by applying a force to the pair of side pillars of each membrane unit in a direction away from each other.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS In the embodiments of FIGS. 1 to 5, the same components as those of the preceding devices of FIGS. The flat sheet membrane element 11 has openings 15 at four inner corners surrounded by a seal 14. The opening 15 also serves as a water collecting port for the permeated water flowing through the membrane (hereinafter referred to as a water collecting port). Three
Reference numerals 0 and 30 denote a pair of thick side pillars extending along one side and the other side of the flat sheet membrane element, and the side pillar 30 is provided with an extension portion 30 ′ vertically protruding from the side portion of the flat sheet membrane element. From the upper and lower extensions, opposed short inward projections 31 project along the upper edge and the lower edge of the flat sheet membrane element. The side pillar 30 is a molded plastic product.

The upper and lower inward projections 31, 31 and the side pillar 3
At the corners formed by the upper part and the lower part of 0, a thin support piece 32 that abuts from one side of the flat membrane element and the upper and lower corners of the other side from the back face each other. Each support piece 3
2 has a recess 33 communicating with the water collecting port 15 at the four corners of the flat membrane element, and a water passage hole 34 that opens the inside of the recess to the outside of the side column. Each recess 33 has a cylindrical wall 35 at the center of the bottom. In addition, each support piece 32 has an annular projection 3 around the depression.
6, the annular projection 36 shallowly digs into the flat sheet membrane element around the water collecting port 15 to perform sealing.

40 is a water collecting port 15 at the four corners of the flat sheet membrane element.
It is a plastic seal cap that closes up from the front, and its size is slightly larger than the diameter of the water collection port. The seal cap has a central leg 41 at the center, which projects into a cylindrical wall 35 provided in the center of the recess of the support piece and is detachably fixed to the support piece. The center leg 41 has a diameter-expanded portion 42 at the tip in this embodiment.
Have. Further, the inner diameter of the upper end portion of the cylindrical wall 35 at the center of the recess of the support piece 32 that receives the central leg 41 and fixes the seal cap is slightly smaller than the enlarged diameter portion 42. Therefore, the seal cap is fixed to the support piece 32 by snap engagement by inserting the central leg into the cylinder wall while pushing and expanding the inlet of the cylinder wall at the expanded diameter portion. The seal cap may be fixed not by the snap engagement described above but by thread engagement by forming a female screw on the inner circumference of the cylinder wall and a male screw on the center leg. The seal cap is also provided with an annular protrusion 43 at the peripheral portion, and when fixed to the support piece as described above, it is set so as to shallowly dig around the water collecting port 15 of the flat sheet membrane element. When the annular projection 43 of the seal cap and the annular projection 36 of the support piece are set at the same position on the front and back sides around the water collecting port of the flat membrane element, the permeation chamber 11 'of the flat membrane element is crushed by both projections. In order to prevent the permeated water from entering the water collecting port, one of the annular protrusions 36 and 43 may be made larger in diameter than the other, and the protrusions may be eaten into the flat sheet membrane element from the front and back at different positions. preferable. In this embodiment, the permeated water is collected from the water collecting ports provided at the four corners. However, instead of all the four corners, one or two of the upper or lower part or the diagonal line may be used as the permeate collecting port, and the rest may simply serve as a function for fixing the membrane element. Also, the description has been given with the support piece provided with the cylindrical wall 35 and the seal cap provided with the central leg 41.
1 may be provided, and the cylindrical wall 35 may be provided on the seal cap.

In order to construct a membrane unit having one flat membrane element, a pair of side columns are arranged along both sides of the flat membrane element 11, whereby upper and lower support pieces 32, 32 of each side column are formed.
Is applied to the upper and lower corners of one side of the flat sheet membrane element and the upper and lower corners of the other side, and the recess 33 in the supporting piece is communicated with the water collecting port 15 of the flat sheet membrane element. 41 is put in the cylindrical wall 35 at the center of the recess, and the water collecting port 15 is closed from the front by a seal cap, and the support pieces 32 and the seal cap 40 are provided around the water collecting ports at the four corners of the flat sheet membrane element.
It is sandwiched between and, and the annular projections 36 and 43 are bited to seal. Since the thickness t of the side pillar is larger than the total thickness of the support piece 32, the flat sheet membrane element 11, and the seal cap 40, when the pair of side pillars are adjacent to each other and the membrane units are arranged in a line in the front-rear direction, A water passage interval 18 occurs between the flat sheet membrane elements.

As shown in the figure, front and rear end plates 50, 51 are arranged so that a plurality of membrane units are arranged in a line in the front-rear direction and the flat membrane elements are tensioned in the width direction to form a membrane unit.
Four support rod members 52 horizontally installed between the four corners of the ...
To use. The supporting rod member of the illustrated embodiment is a tube whose both ends are closed, and a water passage hole 34 for opening the recess 33 in the supporting piece of each membrane unit to the outside of the side column, and a hole formed in the supporting rod member. Are connected by one hose 53, and the supporting rod member also serves as a header. Lower support bar members 52 on the left and right
Is the corner portion formed by the inwardly projecting portion 31 below the pair of side columns 30 and 30 and the extension portion 30 'of the side column, and the upper and left support rod members 52 are the pair of side columns 30 and 30. Ride on the corner formed by the inward protruding portion 31 above and the side column extension 30 '. Since the distance W between the left and right support rod members is dimensioned to tension the flat sheet membrane elements in the width direction, the flat sheet membrane elements of the plurality of membrane units arranged side by side in a row in the front-back direction are strained. The membrane unit thus assembled is immersed in water in a dipping tank as in the conventional case, and the permeated water extraction pipe 2 and the replacement water supply pipe 5 are connected to the four support rod members 52 to perform membrane separation.
In order to individually remove the flat sheet membrane elements, the two upper support frame members 52 can be removed and pulled out from the upper side. Further, one of the end plates 50 and 51 can be attached and detached so that it can be pulled out toward the end plate.

Further, as shown in FIG. 5, an extension portion 30 on a pair of side columns 30 and 30 along both sides of the flat sheet membrane element.
It is also possible to provide an outward projecting portion 37 having a direction opposite to that of the inward projecting portion 31 to the ′, and suspend the outward projecting portion 37 on the left and right support rod members from above. Of course, the lower left and right support rod members are adapted to receive the inward protruding portion 31 below the side pillar and the corner portion of the downward extension portion 30 'of the side pillar. In this case, for any of the membrane units that are lined up in a row in the front-back direction, remove the hose 53, remove the seal caps at the four corners,
The flat sheet membrane unit can be separated from the pair of side columns.

[0013]

As is apparent from the above, according to the present invention, a plurality of membrane units are arranged side by side in a row in the front-rear direction by a horizontal support rod member to form a membrane unit. Then, each membrane unit is assembled by attaching the four corners having the openings of the flat membrane element to the support pieces above and below the pair of side columns, and detachably fixing the seal caps closing the openings from the front to the support pieces. There is. Therefore, any membrane unit constituting the membrane unit can be individually removed from the support rod member and the seal caps at the four corners can be removed to easily separate the flat membrane element from the pair of side columns. Further, the membrane rod can be tensioned by a simple mechanism of applying a force in the direction in which the side columns are separated from each other by the support rod member.

[Brief description of drawings]

FIG. 1 is a front view of a first embodiment of a membrane unit of the present invention with a flat membrane element partially cut away.

FIG. 2 is an enlarged cross-sectional view taken along the line AB of FIG.

FIG. 3 is a perspective view showing a disassembled state of a membrane unit constituting the membrane unit of FIG. 1 and a support rod member.

FIG. 4 is a perspective view of the membrane unit of FIG.

FIG. 5 is a perspective view of a second embodiment of the membrane unit of the present invention.

FIG. 6 is a perspective view in which a part of a flat sheet membrane element is peeled off.

FIG. 7 is an enlarged cross-sectional view of a part of an assembled state of a conventional membrane unit.

FIG. 8 is a flow sheet of a membrane separation device using a membrane unit.

[Explanation of symbols]

 11 Flat Membrane Element 12 Flow Channel Spacer 13 Flat Membrane 14 Seal 15 Opening (Water Collection Port) 30 Side Column 31 Inward Projection 32 Supporting Piece 33 Recess 34 Water Passage 35 Tube Wall 36 Annular Protrusion 37 Outward Projection 40 Seal Cap 41 center leg 42 expanded diameter portion 43 annular protrusion 50 end plate 51 end plate 52 support rod member 53 hose

Claims (1)

[Claims] 1. A support piece having a pair of thick side columns along both sides of a flat sheet membrane element having an opening, provided at upper and lower ends of the side column and communicating with the opening of the flat sheet membrane element. To the flat sheet membrane element, and a seal cap that closes the opening of the flat sheet membrane element is detachably fixed to the support piece, and thus the flat sheet membrane elements are attached horizontally to the pair of side pillars. Immersion type characterized by arranging a plurality of supporting rod members arranged in a line in a stacked state and applying a force to the pair of side columns of each membrane unit in a direction away from each other to tension each flat membrane element Membrane unit of membrane separator.