JP5889693B2 - Immersion flat membrane element and membrane unit using immersion flat membrane element - Google Patents

Description

The present invention relates to, for example, a flat membrane element constituting an immersion type membrane separation apparatus that performs solid-liquid separation and a membrane unit using the immersion type flat membrane element .

2. Description of the Related Art Conventionally, a technique for performing solid-liquid separation using a flat membrane element is known in wastewater treatment by an activated sludge method of organic wastewater that aerobically biodegrades sewage and organic wastewater. In addition, the membrane separation activated sludge treatment method that uses a flat membrane for the activated sludge method is a treatment method with a high concentration of microorganisms and dissolved organic matter, so it can be applied to operations such as protein separation and cell separation from fermentation processes. Technology.
FIG. 17 is an explanatory diagram showing an example of a device for a membrane separation activated sludge treatment method (membrane bioreactor (MBR)) using a flat membrane element.
A membrane unit b composed of a plurality of flat membrane elements c is disposed in the open type liquid tank a. A pipe d for taking out the filtrate is connected to each flat membrane element c. The piping d is provided with a suction pump e. The filtrate is sent to the treated water tank via the pipe d.

To-be-treated water tank a is supplied with the to-be-treated water from the raw water supply pipe f. The raw water supply pipe f is provided with a raw water supply pump g.
An air diffuser h is disposed immediately below each flat membrane element c. A blower i is provided in the air diffuser h.
In this processing apparatus, the water to be treated is supplied to the liquid tank a to be treated by the raw water supply pump g, the air is spouted from the air diffuser h by the drive of the blower i, and the sewage in the tank is swirled by this blown air flow and the suction pump e. By intermittently driving the filtrate passage side of the flat membrane element c by intermittent driving, the pressure on the filtrate side of the flat membrane element c and the pressurized water applied to the submerged flat membrane element c by the water level of the liquid tank a to be treated The treated water obtained by subjecting water to membrane filtration under a transmembrane differential pressure due to pressure and separating a predetermined solid by the membrane via the pipe d can be stored in the treated water tank.

Conventionally, as this type of flat membrane element, for example, a structure in which a spacer and a membrane are pasted on the surface of a filter body or a membrane support is known (see, for example, Patent Document 1).
The flat membrane element of Patent Document 1 has a groove serving as a flow path for the filtrate so that the filtrate flows on the surface of the filter body and the like, and in order to reduce the adhesion and suction pressure of the membrane.
Also, as a membrane support for this type of flat membrane element, a plastic corrugated board in which a plurality of barriers are arranged in parallel between two flat plates molded in parallel in a direction perpendicular to them. A technique using a support plate having a plurality of through holes formed on a flat plate surface (hereinafter referred to as a plastic stage) is known (for example, see Patent Document 2). The treated water is allowed to pass through the permeated water chamber inside the plastic stage via a plurality of flat plate through holes.
Patent Document 2 employs a structure in which a film is attached to the surface of a support plate, which is a plastic stage, and the support plate is held by a frame. A water collection channel is formed in the frame.

Japanese Patent No. 3119773 Japanese Patent No. 3538902

  By the way, in the standard activated sludge method, the concentration of MLSS (Mixed Liquor Suspended Solid), which is the SS concentration of the activated sludge mixture, becomes about 10,000 mg / L after sedimentation due to the problem of sedimentation speed in the sedimentation tank. However, in the case of MBR of the membrane separation activated sludge method, it is size filtration rather than separation by gravity, so the MLSS concentration can be concentrated to a high concentration, and clear membrane filtered water Can be obtained. Since solid-liquid separation of high-concentration MLSS is performed, handling of the cross flow flow rate becomes important. In the case of the immersion type MBR, since the air lift rising flow caused by the bubble rising of the aeration by immersing the membrane in the tank is also used as the cross flow flow, the aeration air forming the flow velocity of the air lift rising flow on the membrane surface The amount is 2 to 4 times greater than the amount of aerated air in the aerobic biological treatment of the standard activated sludge method. In order to effectively use the airlift upflow of crossflow flow formation that determines the processing capacity of this membrane without waste, the longer the length in the height direction of the flat membrane element to be immersed, the more advantageous. It is better to enlarge the element. Also, the air lift upflow that creates a crossflow flow rises while shaking in the liquid, thus vibrating the contacting membrane.

Submerged membrane separators with these characteristics are required to reduce weight (weight reduction), maintain the filtration area ratio, and ensure membrane adhesion strength as the membrane element increases in size. As an energy saving, it is also desired to reduce the filtrate suction pressure for membrane filtration (the membrane filtration pressure is small).
On the other hand, Patent Document 1 raises the following problems.
Since the filtrate that has passed through the membrane flows on the surface of the filter body that does not allow water to pass through the membrane, passing only through the gap between the membrane and the membrane, the suction pressure of the filtrate tends to increase.
A solution is made by forming a plurality of grooves on the surface of the filter body. However, in increasing the size of the membrane element, the suction force is further increased.
In addition, the filter body is a solid plate material, and when the size is increased, the membrane element becomes heavy and handling becomes difficult.

In Patent Document 2, the following problems are raised.
The membrane support is bonded or affixed to the membrane support and fitted into the frame, and the membrane support is a thin material that easily vibrates due to the air lift upward flow. There is concern about peeling between the frame and the boundary surface of the frame and inflow of sludge. As in the embodiments of FIGS. 6 to 8 of Patent Document 2, it is very difficult to finely fix the film and the support material, which are different materials, in a fine line.
In addition, when the size is increased, the filtration area ratio in the membrane element is reduced when the strength of the frame is increased.

The present invention has been made to solve such a conventional problem, and its purpose is to reduce the filtrate suction pressure after membrane permeation (the membrane filtration pressure is small) and to reduce the weight associated with the increase in size ( It is an object of the present invention to provide a submerged flat membrane element and a membrane unit using the submerged flat membrane element that can ensure the membrane adhesion strength and maintain the filtration area ratio.

According to the first aspect of the present invention, a plurality of partition walls are fixed in parallel at a predetermined interval between two flat plate members which are perforated with innumerable openings and arranged in parallel. A membrane support composed of a plastic stage, which is a corrugated cardboard sheet made of plastic formed by forming a filtrate flow path between, and one side of the upper end of the membrane support is supported by contact The first shelf is formed in a gate shape with a length shorter than half of the height of the frame body from the upper end to the lower end of the frame body so as to be flush with one outer surface of the frame body. In addition, the second shelf that supports the other side surface of the lower end of the membrane support is in contact with the other outer surface of the frame body from the lower end to the upper end of the frame body. provided with, respectively, as a reverse gate-shape at a height half shorter than the length of the frame body Te, before A frame member comprising a frame body and the water collecting nozzle and the first ledge and a second ledge providing a water collecting nozzle outside of the frame body, and a spacer disposed on said membrane support, disposed on the spacer The membrane support has a top end portion of the membrane support itself in a virtual gap on each shelf extension line between the first shelf and the second shelf. While sliding the side part of the membrane support on the upper surface of the two shelf parts, it is moved toward the upper end of the first shelf part, and the lower end part of the membrane support part is placed on the inner peripheral surface of the frame member. Assembled in the frame member so that a water collecting channel leading to the water collecting nozzle is formed between the inner peripheral surface of the frame member and the opening end portion of the filtrate channel, , And is welded around the frame member.

In the invention according to claim 2, a plurality of partition walls are fixed in parallel at a predetermined interval between two flat plate materials that are perforated with innumerable openings and are arranged in parallel. A membrane support composed of a plastic stage, which is a corrugated cardboard sheet made of plastic formed by forming a filtrate flow path between, and one side of the upper end of the membrane support is supported by contact The first shelf is formed in a gate shape with a length shorter than half of the height of the frame body from the upper end to the lower end of the frame body so as to be flush with one outer surface of the frame body. In addition, the second shelf that supports the other side surface of the lower end of the membrane support is in contact with the other outer surface of the frame body from the lower end to the upper end of the frame body. provided with, respectively, as a reverse gate-shape at a height half shorter than the length of the frame body Te, before Said frame body and the frame member composed of the first ledge second ledge and the water collecting nozzle providing a water collecting nozzle outside of the frame body, and a spacer disposed on said membrane support, on the spacer The membrane support is provided with a virtual gap on each shelf extension line between the first shelf and the second shelf, the upper end of the membrane support itself, The side of the membrane support is moved toward the upper end of the first shelf while sliding the side of the membrane support on the upper surface of the second shelf, and the lower end of the membrane support is placed on the inner peripheral surface of the frame member And assembling so that a water collecting channel leading to the water collecting nozzle is formed between the inner peripheral surface of the frame member and the opening end of the filtrate flow channel, and the flat membrane Is overlapped with the spacer and the periphery of the spacer is welded to the periphery of the frame member. The features.

The invention according to claim 3 is the submerged flat membrane element according to claim 1 or 2, wherein the water collection nozzle is provided at one end or both ends of the membrane support and the frame member. as lead to collection waterway being formed between the circumferential surface, characterized in that formed on one or both sides of the end portion of the one end portion or both of the frame member.
The invention according to claim 4 is the immersion flat membrane element according to any one of claims 1 to 3, wherein the membrane support is screwed to the first shelf and / or the second shelf. Or it is fixed by riveting or welding .

The invention according to claim 5 is the submerged flat membrane element according to any one of claims 1 to 4, wherein the frame member is made of ABS resin (Acrylonitrile, Butadiene, Styrene). Polymerized synthetic resin) or PP (polypropylene), and the spacer is made of PE (polyethylene) resin, CPE (chlorinated polyethylene) resin, PP (polypropylene) resin, PVDF (polyvinylidene fluoride) resin, PAN (polyacrylonitrile). ) Resin, PI (polyimide) resin, PES (polyether sulfone) resin, PS (polysulfone) resin, or CA (cellulose acetate) resin, which is composed of a non-woven fabric or net, and the flat membrane is made of PE (polyethylene) resin, CPE (Chlorinated polyethylene) resin, PP (polypropylene) resin, PVDF (poly Kka vinylidene) resins, PAN (polyacrylonitrile) resin, PI (polyimide) resin, PES (polyether sulfone) resin, PS (polysulfone) resin or CA (that is composed of a film member made of cellulose acetate) resins the shall be the feature.

According to a sixth aspect of the present invention, in the membrane unit using the submerged flat membrane element according to any one of the first to fifth aspects, the frame member includes a flat surface of another frame member adjacent to the frame member. A protrusion projecting from at least one outer surface of the frame member to maintain a predetermined distance from the membrane, and a connecting bolt is inserted into the central portion as a connecting bolt receiving portion toward the outside of the frame member. An interval holding member is formed to form a projection provided with a concave groove along the entire length of both outer side portions, and on both sides parallel to the film surface of the frame member to be laminated, the interval holding member of the frame member is provided. A holding panel having a recessed groove is installed at a position corresponding to the protrusion, and the frame member and the holding panel to be stacked are integrated by passing through the recessed groove with the connecting bolt. characterized in that that.

According to the present invention, the solution flow path can be secured by the membrane support member (plastic stage), and moreover, it can be constructed without special consideration for the liquid tightness with the water collecting path, and the suction pressure of the filtrate can be reduced.
In addition, by using a hollow plastic stage as a membrane support member, even when the size is increased, the weight can be reduced as compared with a membrane element using a filter body (filter plate).
In addition, a flat membrane is welded to the frame member, and a spacer is interposed between the flat membrane and the membrane support member, so that unnecessary vibration of the membrane support member due to air lift upflow caused by bubbles is suppressed, and a rigid that is difficult to vibrate By suppressing the vibration of the flat membrane welded portion of the frame member, the membrane element is free from peeling or sludge inflow at the boundary surface between the flat membrane and the frame member.

In addition, in a rectangular parallelepiped membrane element, by arranging the membrane support member so that the flow of the filtrate in the membrane support member is parallel to the long side of the membrane element, the path in which the filtrate flow rate in the membrane support member is slow The water collecting passage having a high flow rate from the membrane support member to the water collecting nozzle can be formed short, and the suction pressure can be further reduced.
In addition, when the membrane support member is installed on the frame member, the spacer and the flat membrane are fixed after being inserted into the first shelf and the second shelf and temporarily fixed, so that the assembly is very easy.

It is a partially cutaway perspective view showing an immersion flat membrane element according to an embodiment of the present invention. It is a perspective view which expands and shows the principal part of FIG. It is sectional drawing along the AA line of FIG. It is an enlarged view which shows the state which welded the spacer and the flat film to the 1st frame member. It is a front view of the 1st frame member of FIG. It is a perspective view of the 1st frame member of FIG. It is a perspective view which shows the state which attached the assembly member to the immersion type flat membrane element of FIG. It is a perspective view which shows the assembly of the membrane unit which uses the immersion type flat membrane element which attached the assembly | attachment member of FIG. It is a front view of the assembled membrane unit. FIG. 10 is a top view of the membrane unit of FIG. 9. FIG. 10 is a side view of the membrane unit of FIG. 9. It is a front view which shows a 2nd frame member. It is a front view which shows a 3rd frame member. It is sectional drawing of the immersion type flat membrane element using the frame member of FIG. It is a front view which shows a 4th frame member. It is a front view which shows a 5th frame member. It is explanatory drawing which shows an example of the apparatus of the membrane separation activated sludge process method (Membrane Bioreactor (MBR)) which uses a flat membrane element.

Hereinafter, the present invention will be described based on embodiments shown in the drawings.
1 to 6 show an immersion flat membrane element 1 according to an embodiment of the present invention.
The submerged flat membrane element 1 according to the present embodiment is provided with a first shelf portion 12a and a second shelf portion 12b at the upper and lower end portions and two water collecting nozzles 13 facing the outer portion 11b. Together with the frame member 10, the membrane support member 20 disposed between the first shelf portion 12a and the second shelf portion 12b of the first frame member 10, the spacer 30 disposed on the membrane support member 20, and the spacer 30 The flat film 40 is overlapped and the periphery of the spacer 30 is welded to the periphery of the first frame member 10.

The first frame member 10 includes, for example, a frame main body 11 made of plastic such as ABS resin (acrylonitrile, butadiene, styrene copolymer) or PP (polypropylene) resin, and one end of the frame main body 11. 1st shelf part 12a provided in one side part of (upper end part of FIG. 1), and 2nd shelf provided in the other side part of the other edge part (lower end part of FIG. 1) of frame main body 11 The part 12b and the water collection nozzle 13 provided so that it may communicate with the internal peripheral surface 11a in the outer side part 11b of one edge part (upper end part of FIG. 1) of the frame main body 11 are provided.
The first end portion 12a and the second end portion 12b are directed from one end portion (upper end portion in FIG. 1) of the frame body 11 toward the other end portion so that the membrane support member 20 is sandwiched between both end portions. It is provided so as to be flush with the outer surface of the frame main body 11 so as to form a gate shape.
An opening 13 a that communicates with the water collection nozzle 13 is provided in the outer portion 11 b and the inner peripheral surface 11 a. In this embodiment, the plate | board thickness of the 1st frame member 10 was about 6 mm, for example.

For example, the membrane support member 20 is formed by fixing a plurality of partition walls 23 at a predetermined interval between two flat plates 21 in which an infinite number of openings 22 of about 0.5 mm to 3 mm are perforated and arranged in parallel. This is composed of a plastic stage 20A formed by forming a filtrate channel 24 between the flat plate material 21 and each partition wall 23. The plastic stage 20A is a corrugated cardboard sheet made of plastic such as PP (polypropylene) resin, PE (polyethylene) resin, PC (polycarbonate) resin, and the like, for example, with a thickness of about 2 mm to 5 mm.
The membrane support member 20 has a lateral width substantially equal to the lateral width X between the inner peripheral surfaces 11a of the frame main body 11 of the first frame member 10 and a vertical width of the inner peripheral surface 11a of the frame main body 11 of the first frame member 10. It is slightly shorter than the vertical width Y between them. The reason why the vertical width is slightly shorter than the vertical width Y between the inner peripheral surfaces 11a of the frame main body 11 of the first frame member 10 is that the filtrate is supplied from the filtrate channels 24 of the membrane support member 20 to the first frame. This is because the water collecting passage 14 for guiding the member 10 to the water collecting nozzle 13 is formed between the inner peripheral surface 11 a of the frame body 11. In this embodiment, the plate | board thickness of the film | membrane support member 20 was about 2 mm, for example.

The spacers 30 are, for example, PE (polyethylene) resin, CPE (chlorinated polyethylene) resin, PP (polypropylene) resin, PVDF (polyvinylidene fluoride) resin, PAN (polyacrylonitrile) resin, PI (polyimide) resin, PES ( It is comprised with the nonwoven fabric or net | network which consists of a polyether sulfone) resin, PS (polysulfone) resin, or CA (cellulose acetate) resin. In the present embodiment, for example, two spacers 30 having a thickness of about 0.1 mm to 0.2 mm are stacked and used.
The flat film 40 is made of PE (polyethylene) resin, CPE (chlorinated polyethylene) resin, PP (polypropylene) resin, PVDF (polyvinylidene fluoride) resin, PAN (polyacrylonitrile) resin, PI (polyimide) resin, PES (polyethylene). It is composed of a membrane member made of ether sulfone) resin, PS (polysulfone) resin or CA (cellulose acetate) resin. In the present embodiment, the thickness of the flat membrane 40 is about 0.1 mm to 0.2 mm.

Next, assembly of the submerged flat membrane element 1 according to this embodiment will be described.
First, the upper end 20a of the membrane support member 20 is placed in the virtual gap on the respective shelf extension lines between the first shelf 12a and the second shelf 12b of the first frame member 10 in the second shelf 12b. The lower end portion 20b of the membrane support member 20 is moved on the inner peripheral surface 11a of the first frame member 10 while sliding the side portion of the membrane support member 20 toward the upper surface of the first shelf portion 12a. The membrane support member 20 is formed such that a gap serving as the water collecting channel 14 is formed between the upper end portion 20a of the membrane support member 20 and the inner peripheral surface 11a on the upper end portion side of the first frame member 10. The upper end portion 20a of the film is in contact with the inner surface side of the first shelf portion 12a, and the lower end portion 20b of the membrane support member 20 is in contact with the inner surface side of the second shelf portion 12b.
Next, when the submerged flat membrane element 1 according to the present embodiment is attached to an apparatus of a membrane separation activated sludge treatment method (Membrane Bioreactor (MBR)) and cleaned and regenerated, the membrane support member 20 In order to prevent the membrane support member 20 from being detached from the first shelf 12a and the second shelf 12b, for example, screwing, riveting, or welding to the first shelf 12a and the second shelf 12b. Fixed by.

Next, as shown in FIGS. 1 to 4, the film supporting member 20 is covered so that the periphery of the two spacers 30 overlaps the periphery of the first frame member 10.
Next, as shown in FIGS. 1 to 4, the flat film 40 is covered with the spacer 30 so that the periphery overlaps the periphery of the first frame member 10.
Next, the welding apparatus provided with the uneven | corrugated shaped welding tool is arrange | positioned in the outer periphery 41 of the flat film 40, and the overlap part 42 of the flat film 40 and the spacer 30, and the 1st frame member 10, the flat film 40, and a spacer 30 are melt-bonded and bonded together. Thus, for example, as shown in FIG. 4, a welded portion 45 between the first frame member 10 and the flat membrane 40 is formed, and a welded portion 46 between the first frame member 10, the flat membrane 40 and the spacer 30 is formed. Can be formed.
Examples of the welding apparatus include an ultrasonic welding machine, a vibration welding machine, an induction welding machine, a high frequency welding machine, a semiconductor laser welding machine, a thermal welding machine, and a spin welding machine.
The immersion flat membrane element 1 which concerns on this embodiment can be obtained by the above.

  According to the submerged flat membrane element 1 according to the present embodiment configured as described above, the first and second end portions 20a and 20b of the membrane support member 20 are symmetrically arranged at both end portions of the first frame member 10, respectively. Since it is fixed between the shelf portion 12a and the second shelf portion 12b, the membrane support member 20 composed of the plastic stage 20A can be reliably disposed in the first frame member 10. In addition, since the membrane support member 20 is configured by the plastic stage 20A in which an infinite number of openings 22 are perforated, the suction pressure of the filtrate filtered by the flat membrane 40 can be reduced. Moreover, since the flat film 40 is welded to both surfaces of the first frame member 10, water can be efficiently filtered by the flat film 40. Since the membrane support member 20 is composed of the plastic stage 20A, the weight is reduced. The amount of filtration can be adjusted by the number of openings 22 and the hole diameter of the plastic stage 20A. Since the spacer 30 is disposed between the flat membrane 40 and the membrane support member 20, there is no possibility that the flat membrane 40 is damaged by the plastic stage 20A. Since the flat film 40 is attached to the first frame member 10 by welding, there is an advantage that peeling of the flat film 40 hardly occurs.

Next, the membrane unit 50 using the submerged flat membrane element 1 according to the present embodiment will be described with reference to FIGS.
In the membrane unit 50 according to this example, for example, as shown in FIG. 7, the connection between the immersion type flat membrane element 1 and the distance between the immersion type flat membrane element 1 are maintained on both outer side portions 11 b of the immersion type flat membrane element 1. An interval holding member 51 having a function for this purpose is integrated. The spacing member 51 may be formed integrally with the first frame member 10 of the submerged flat membrane element 1 or may be fixed or welded to the first frame member 10 of the submerged flat membrane element 1.

  The interval holding member 51 is provided with, for example, eight connecting bolt receiving portions 52 at equal intervals along the entire length of both outer side portions 11 b of the submerged flat membrane element 1. The protrusion 53 having a half length has a lateral width that can be formed. The connecting bolt receiving portion 52 is formed of a protrusion having a substantially chevron shape in cross section provided with a concave groove 52a into which the connecting bolt is inserted at the center. The protrusions 53 are formed in parallel to the outer side portions 11b of the submerged flat membrane element 1, and when the submerged flat membrane element 1 is laminated, the adjacent spacing members 51 come into contact with each other. For example, an interval of about 6 mm to 7 mm can be formed between 1.

Next, the assembly of the membrane unit 50 using the submerged flat membrane element 1 according to the present embodiment will be described based on FIGS.
First, as shown in FIG. 8, a predetermined number of submerged flat membrane elements 1 having the spacing members 51 shown in FIG. 7 are arranged in parallel with the flat membrane 40 in the vertical direction. A predetermined interval is maintained between the submerged flat membrane elements 1 by the protrusions 53 of the interval holding member 51.
Next, the control panel 55 larger than the immersion flat membrane element 1 is installed on both surfaces of the arranged immersion flat membrane elements 1. The holding panel 55 is provided with a concave groove 55 a into which the connecting bolt is inserted at a position corresponding to the eight connecting bolt receiving portions 52 of the spacing member 51.

Next, the connecting bolt 56 is inserted into the connecting bolt receiving portion 52 and the recessed groove 55a, and the washer 57 and the nut 58 are attached to the connecting bolt 56 so that each submerged flat membrane element 1 does not move together with the holding panel 55. To fix.
Next, a frame 59 constituted by an angle or the like is attached to the left and right end sides of the submerged flat membrane element 1 assembled for reinforcement so as to be removable via a fixture 60. Further, the side holding plates 61 are attached to the left and right ends of the submerged flat membrane element 1 assembled for reinforcement so as to be removable. A suspension plate 62 is attached to the frame 59.
Next, the water collection pipe 63 is installed on the upper part of both side surfaces of the submerged flat membrane element 1, and the water collection nozzle 13 and the water collection pipe 63 are connected by a tube 64.
Thus, the membrane unit 50 can be obtained.

The membrane unit 50 configured in this way is applied to an apparatus for membrane separation activated sludge treatment method (Membrane Bioreactor (MBR)), for example, as shown in FIG.
The effect | action of this processing apparatus is demonstrated based on FIGS. 1-11 using FIG.
Water to be treated is supplied to the liquid tank a to be treated by the raw water supply pump g, air is ejected from the diffuser pipe h by driving the blower i, and the waste water in the tank is swirled by this jet stream and intermittently driven by the suction pump e. Thus, the filtrate passage side of each submerged flat membrane element 1 of the membrane unit 50 is intermittently depressurized, and water is removed under the transmembrane differential pressure due to the depressurization of the submerged flat membrane element 1 on the filtrate side. 40 can be permeated and stored in the treated water tank via the water collecting pipe 63.

According to this processing apparatus, the filtrate that has permeated through the flat membrane 40 flows into the filtrate channels 24 from the countless openings 22 of the membrane support member 20 through the spacers 30, and is collected in the collecting channels 14. Since it sends out to the water collection pipe 63 via the tube 64, the suction pressure of a filtrate can be reduced.
Further, since the submersible flat membrane element 1 has a rectangular parallelepiped shape, the membrane support member 20 is arranged so that the flow of the filtrate in the membrane support member 20 is in the horizontal direction with the long side of the submersible flat membrane element 1. Therefore, the water collecting passage 14 from the membrane support member 20 to the water collecting nozzle 13 can be formed short, and the suction pressure can be further reduced.

Further, since the flat membrane 40 is superimposed on the membrane support member 20 and the first frame member 10 via the spacer 30, it does not come into contact with the membrane support member 20 or the first frame member 10 during decompression. Therefore, the flat membrane 40 is not damaged by the membrane support member 20 or the first frame member 10 during decompression.
At this time, between the immersion flat membrane elements, the adjacent spacing members 51 are in contact with each other, and, for example, an interval of about 6 mm to 7 mm can be formed, so that the flat membranes of all the immersion flat membrane elements 1 can be formed. Water can be passed through 40.
The membrane unit 50 configured as described above can loosen the whole bolts at the time of maintenance, remove the frame 59 and the connection fixing bolt 56 on one side surface, and extract the membrane element 1 from this side surface side.

Although the said embodiment demonstrated the case where the water collection nozzle 13 was provided in the both sides of one edge part (upper end part of FIG. 1) of the 1st frame member 10, this invention is not limited to this, You may provide the nozzle 13 in the both sides of the other edge part (lower end part of FIG. 1) of the 1st frame member 10. As shown in FIG.
Moreover, although the said embodiment demonstrated the case where the water collection nozzle 13 was provided in the both sides of the one edge part of the 1st frame member 10, this invention is not limited to this, For example, FIGS. As shown in FIG. 5, the water collection nozzle 13 may be provided at both ends of the second frame member 10A or the third frame member 10B.

Further, in the upper embodiment, the case where the first shelf portion 12a and the second shelf portion 12b provided in the first frame member 10 have a portal shape has been described, but the present invention is not limited thereto, for example, As in the fourth frame member 10 </ b> C shown in FIG. 15, the first shelf portion 12 a and the second shelf portion 12 b may be provided on both sides along the longitudinal direction of the frame member. The first shelf portion 12 a and the second shelf portion 12 b can hold both end portions of the membrane support member 20 in the same manner as the first frame member 10.
In this case, the weight can be reduced as compared with the immersion flat membrane element 1 using the first frame member 10.
In the fourth frame member 10C, the attachment position of the water collecting nozzle 13 may be provided in the same manner as the second frame member 10A or the third frame member 10B shown in FIGS.

Further, in the upper embodiment, the case where the first shelf portion 12a and the second shelf portion 12b provided in the first frame member 10 have a portal shape has been described, but the present invention is not limited thereto, for example, As in the fifth frame member 10D shown in FIG. 16, the first shelf portion 12a and the second shelf portion 12b may be provided at both ends of the frame member. The first shelf portion 12 a and the second shelf portion 12 b can hold both end portions of the membrane support member 20 in the same manner as the first frame member 10.
In this case, the weight can be reduced as compared with the immersion flat membrane element 1 using the first frame member 10.
In the fifth frame member 10C, the attachment position of the water collecting nozzle 13 may be provided in the same manner as the second frame member 10A or the third frame member 10B shown in FIGS.

  Further, in the above embodiment, a welding apparatus provided with an uneven welding tool is disposed on the outer periphery 41 of the flat membrane 40 and the overlapping portion 42 of the flat membrane 40 and the spacer 30, and the first frame member 10 and the flat membrane 40 are flat. For example, as shown in FIG. 4, a welded portion 45 between the first frame member 10 and the flat film 40 is formed by bonding the film 40 and the spacer 30 together while being melted. Although the case where the welding part 46 of the frame member 10, the flat film 40, and the spacer 30 is formed has been described, the present invention is not limited to this, and the first frame member 10 and the flat film 40 may be welded. .

Moreover, in the said embodiment, although the case of the double-sided processable type | mold which has arrange | positioned the spacer 30 and the flat film 40 on the outer side of each of the two flat plate materials 21 of the film | membrane support member 20, this invention is not limited to this, A single-side processable type in which the opening 22 is provided only on one side of the flat plate 21 of the membrane support member 20 and the spacer 30 and the flat membrane 40 are disposed only on the flat plate 21 side may be used.
Moreover, in the assembly of the membrane unit 50 shown in FIGS. 7 to 11, for example, as shown in FIG. 7, the connection of the immersion flat membrane element 1 to the outer side portions 11b of the immersion flat membrane element 1 and the immersion flat membrane are performed. Although the case where the interval holding member 51 having a function for maintaining the interval between the elements 1 is integrated has been described, the present invention is not limited to this, and any configuration can be used as long as it can be assembled as a membrane unit.

DESCRIPTION OF SYMBOLS 1 Submerged flat membrane element 10 1st frame member 11 Frame main body 11a Inner peripheral surface 11b Outer part 12a First shelf part 12b Second shelf part 13 Water collection nozzle 20 Membrane support member 20A Plastic stage 21 Flat plate material 22 Opening 23 Partition 24 Filtrate channel 30 Spacer 40 Flat membrane 45, 46 Welded part

Claims (6)

A plurality of partition walls are fixed in parallel between two flat plates arranged in parallel by drilling innumerable openings, and a filtrate flow path is formed between the two flat plates and each of the partition walls. A membrane support composed of a plastic corrugated cardboard sheet made of plastic made of
The frame from the upper end to the lower end of the frame body so that the first shelf supporting the one side of the upper end of the membrane support is in contact with one outer surface of the frame body The other outer surface of the frame main body has a second shelf part that abuts and supports the other side surface of the lower end of the membrane support so as to have a gate shape with a length shorter than half the height of the main body. Are provided so as to be in a reverse portal shape with a length shorter than half the height of the frame body from the lower end of the frame body to the upper end so as to be flush with each other, and on the outer part of the frame body A frame body comprising a frame main body, a first shelf, a second shelf, and a water collection nozzle for providing a water collection nozzle;
A spacer disposed on the membrane support;
A flat membrane disposed on the spacer,
The membrane support supports the membrane on the upper surface of the second shelf, with the upper end of the membrane support itself in a virtual gap on each shelf extension line between the first shelf and the second shelf. The frame member is moved by moving toward the upper end of the first shelf while sliding the side of the body, and the lower end of the membrane support is placed on the inner peripheral surface of the frame member and assembled. Is disposed on the frame member so that a water collecting channel leading to the water collecting nozzle is formed between the inner peripheral surface of the liquid collecting channel and the opening end of the filtrate flow channel.
The flat membrane is welded around the frame member. An immersion type flat membrane element. A plurality of partition walls are fixed in parallel between two flat plates arranged in parallel by drilling innumerable openings, and a filtrate flow path is formed between the two flat plates and each of the partition walls. A membrane support composed of a plastic corrugated cardboard sheet made of plastic made of
The frame from the upper end to the lower end of the frame body so that the first shelf supporting the one side of the upper end of the membrane support is in contact with one outer surface of the frame body The other outer surface of the frame main body has a second shelf part that abuts and supports the other side surface of the lower end of the membrane support so as to have a gate shape with a length shorter than half the height of the main body. Are provided so as to be in a reverse portal shape with a length shorter than half the height of the frame body from the lower end of the frame body to the upper end so as to be flush with each other, and on the outer part of the frame body A frame member comprising the frame main body, the first shelf portion, the second shelf portion, and the water collection nozzle provided with the water collection nozzle ;
A spacer disposed on the membrane support;
A flat membrane disposed on the spacer,
The membrane support supports the membrane on the upper surface of the second shelf, with the upper end of the membrane support itself in a virtual gap on each shelf extension line between the first shelf and the second shelf. The frame member is moved by moving toward the upper end of the first shelf while sliding the side of the body, and the lower end of the membrane support is placed on the inner peripheral surface of the frame member and assembled. Is disposed on the frame member so that a water collecting channel leading to the water collecting nozzle is formed between the inner peripheral surface of the liquid collecting channel and the opening end of the filtrate flow channel.
The flat membrane is overlapped with the spacer, and the periphery of the spacer is welded to the periphery of the frame member. In the immersion type flat membrane element according to claim 1 or 2,
The water collecting nozzle is connected to one end of the frame member so as to communicate with a water collecting passage formed between one or both ends of the membrane support and the inner peripheral surface of the frame member. Alternatively, the immersion flat membrane element is formed on one side or both sides of both ends. In the submerged flat membrane element according to any one of claims 1 to 3,
The submerged flat membrane element , wherein the membrane support is fixed to the first shelf and / or the second shelf by screwing, riveting, or welding . In the submerged flat membrane element according to any one of claims 1 to 4,
The frame member is made of ABS resin (Acrylonitrile, butadiene (Butadiene), styrene (Styrene) copolymer synthetic resin) or PP (polypropylene),
The spacer is made of PE (polyethylene) resin, CPE (chlorinated polyethylene) resin, PP (polypropylene) resin, PVDF (polyvinylidene fluoride) resin, PAN (polyacrylonitrile) resin, PI (polyimide) resin, PES (polyether). A non-woven fabric or net made of a sulfone) resin, PS (polysulfone) resin or CA (cellulose acetate) resin,
The flat membrane is made of PE (polyethylene) resin, CPE (chlorinated polyethylene) resin, PP (polypropylene) resin, PVDF (polyvinylidene fluoride) resin, PAN (polyacrylonitrile) resin, PI (polyimide) resin, PES (polyethylene). A submerged flat membrane element comprising a membrane member made of ethersulfone) resin, PS (polysulfone) resin, or CA (cellulose acetate) resin . In the membrane unit using the submerged flat membrane element according to any one of claims 1 to 5 ,
In the frame member,
A protrusion projecting from at least one outer surface of the frame member for maintaining a predetermined distance from a flat membrane of another frame member adjacent to the frame member;
A projecting portion provided with a concave groove into which a connecting bolt is inserted into a central portion as a connecting bolt receiving portion toward the outside of the frame member,
Is added along the entire length of both outer side portions,
On both sides parallel to the film surface of the frame member to be laminated,
Each holding panel provided with a concave groove at a position corresponding to the protrusion of the spacing member of the frame member,
The frame member and the restraining panel to be laminated are integrated by attaching through the concave groove with the connecting bolt.
A membrane unit using a submerged flat membrane element.

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