JP2005144241A - Filtration device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To recover or retain good filtration performance of membrane bundled bodies functioning as a separation membrane by diffusion without affecting the filtration performance of the membrane bundled bodies, i.e., a separation membrane and to retain sufficient filtration performance for a long period of time. <P>SOLUTION: The filtration device carries out solid/liquid separation by permeating a liquid to be treated containing a suspension component through a membrane module for immersion type aspiration filtration or external pressure filtration. The membrane module is constituted of a membrane element in which both ends of a large number of hollow fiber membranes in the axial direction are bundled in layers and a plurality of the bundled bodies are adjacently arranged vertically with spaces between the bodies. A diffusion pipe for jetting gas toward an axis direction of the membrane bundled bodies to carry out bubbling is faced to the spaces. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  TECHNICAL FIELD The present invention relates to a filtration apparatus that performs solid-liquid separation by allowing a liquid to be treated containing a suspended component to permeate through a membrane module, and particularly relates to a filtration apparatus that includes an air diffuser that performs air bubbling with bubbles from an air diffuser. It is.

  Many hollow fiber membranes are concentrically arranged in a circular shape, and one or both ends are fixed with a fixing member in an open state, and the membrane module is used as a water collection part. Used by being attached to the device. Conventionally, membrane modules have been widely used in the field of so-called microfiltration such as purification of river water and lake water. In addition, not only in the water purification field, recently, many studies have been made on highly polluted water treatment applications such as secondary treatment and tertiary treatment of sewage, and filtration of drainage, industrial wastewater, industrial water, and the like.

  In both cases of purified water and highly polluted water treatment, when the filtration treatment is continued by the filtration device using the membrane module, suspended components contained in the liquid to be treated are deposited on the membrane surface or between the membranes. Causes blockage. That is, the hollow fiber membranes are fixedly integrated with each other through the deposit, and the effective membrane area of the hollow fiber membrane in the membrane module is reduced, resulting in a decrease in permeation flow rate.

  For this reason, a cleaning operation is periodically performed to remove deposits on the film surface. Cleaning is a method in which air is introduced from the lower part of the membrane module while the immersion tank is filled with the liquid to be treated, and the film surface deposit is peeled off by air bubbling that vibrates the hollow fiber membrane by the supplied bubbles. Be taken.

  For example, in Japanese Patent No. 30141448 (Patent Document 1), as shown in FIG. 10, air bubbles supplied from air diffuser holes 102 a of an air diffuser plate 102 provided below a sheet-like flat hollow fiber membrane module 101 are used. In the method of filtering liquid while performing air bubbling continuously or intermittently on the hollow fiber membrane 103, the membrane module 101 is disposed so that the sheet surface is in the vertical direction and the hollow fiber membrane is in the horizontal direction, A filtration method in which only the hollow fiber membrane 103 is vibrated by air bubbling is disclosed.

  In JP-A-8-215548 (Patent Document 2), as shown in FIG. 11, one end portion 106 or both end portions 106 and 107 of the hollow fiber membrane 105 are fixed by a fixing member while being kept open. A membrane module is disclosed in which a water function is provided and a diffuser hole 106a is provided in one end (lower end) 106 to provide a diffuser function, and the hollow fiber membrane 105 is subjected to a membrane cleaning by an air bubbling cleaning method.

  Furthermore, in Japanese Patent Publication No. 7-61420 (Patent Document 3), as shown in FIG. 12, a large number of hollow fiber filtration membranes 110 are arranged in an outer cylinder 111, and a porous pipe 112 is mixed in the hollow fiber bundle. Thus, there is disclosed a filter that introduces air from below the porous pipe 112, vibrates the hollow fiber while raising the bubbles along the porous pipe 112, and performs air bubbling.

  However, in the filtration method described in the above-mentioned Japanese Patent No. 30141448 (FIG. 10), since air is diffused over the entire area of the hollow fiber membrane 103 from the air diffuser holes 102a of the air diffuser plate 102, air is sufficiently diffused. For this purpose, it is necessary to dispose adjacent sheet-like flat hollow fiber membrane modules 101 apart from each other to some extent, and it is difficult to install the membranes at high density. Therefore, the volume of the membrane installation part is increased. Further, if only the entire aeration is performed from the lower side of the membrane module 101, only the surface of the hollow fiber membrane 103 is aerated, and there is an aeration between the membranes, particularly in the vicinity of the water collecting portion where the membrane is likely to block. There is an inadequate problem.

  Similarly, in the membrane module described in the above-mentioned JP-A-8-215548 (FIG. 11), one end portion (lower water collecting pipe) 106 of the membrane module is provided with an air diffusion structure and diffused from the air diffusion holes 106a. For this reason, the air is diffused only on the outer surface side of the hollow fiber membrane 105 and does not reach the inner surface side, which is not sufficient in terms of cleaning efficiency. In addition, there is a problem that it cannot be applied to a membrane module in which a large number of hollow fiber membranes are concentrically arranged in a circular shape.

  Furthermore, in the filter described in the above Japanese Patent Publication No. 7-61420 (FIG. 12), a plurality of porous pipes 112 are mixed in a hollow fiber bundle in which a number of hollow fiber filtration membranes 110 are arranged in a circular shape. Therefore, there is a problem that air diffusion between the films is insufficient.

On the other hand, in the diffuser in the conventional filtration processing facility, there is a problem of obstruction of the diffuser holes due to clogging of the diffuser part during long-term use. That is, in the case where the air diffuser 106a is provided at one end (potting part) 106 of the membrane module described in JP-A-8-215548, and the air diffuser 106a is obstructed by sludge or the like, the air diffuser Is difficult to replace. Therefore, although the durability and operability of the membrane itself are sufficiently maintained, the entire membrane module has to be replaced, which is not economical and takes time to replace the membrane module. Further, in the case where air is diffused from the air diffuser installed separately from the membrane module 101 below the membrane module 101 described in the above-mentioned Patent No. 30141448, when the air diffuser hole 102a of the air diffuser plate 102 is blocked, After the entire membrane module is lifted, it is necessary to take the diffuser out of the immersion tank and replace it. Even if the diffuser is not taken out, it is necessary to clean the clogging of the diffuser holes after all the water in the immersion tank has been drained, and in any case, much work is required for the replacement work and the cleaning work.
Japanese Patent No. 30141448 JP-A-8-215548 Japanese Patent Publication No. 7-61420

  The present invention has been made in view of the above-described problems, and the suspended components deposited on the membrane surface or between the membranes by continuation of membrane filtration can be efficiently washed and removed by air bubbles from the air diffuser. It is an object of the present invention to provide a filter device that can prevent the air holes from being blocked at the time of air bubbling cleaning, and can easily recover the function even if the air holes are blocked.

  In order to solve the above-mentioned problems, the present invention is a filtration device for performing solid-liquid separation by allowing a liquid to be treated containing a suspended component to permeate a membrane module for immersion type suction filtration or external pressure filtration, wherein the membrane The module is constituted by a membrane element in which a plurality of hollow fiber membranes, which are formed by concentrating both ends in the axial direction of the hollow fiber membrane in a layered manner, are provided with a plurality of gap portions and arranged adjacent to each other in the vertical direction. There is provided a filtration device characterized by facing a diffuser tube for bubbling by ejecting a gas in the axial direction of a membrane focusing body.

In the filtration device of the present invention having the above-described configuration, each of the air diffusers is disposed in the gap formed between the adjacent membrane focusing bodies, and the gas is ejected in the axial direction of the membrane focusing bodies. Air bubbling acts on almost the entire outer peripheral surface of the membrane focusing body and on both surfaces of each membrane focusing body, and each membrane focusing body is efficiently swung to remove suspended components deposited on the membrane surface or between the membranes. It can be peeled off.
In addition, since the thin air diffuser is arranged in the gap between adjacent film converging bodies, each film converging body can be arranged with high density just by providing a space of the width of the air dispersal pipe, and the filtration performance Can be kept high.

  Further, the present invention is a filtration apparatus for performing solid-liquid separation by allowing a liquid to be treated containing a suspended component to permeate a membrane module for immersion type suction filtration or external pressure filtration. A membrane converging body obtained by concentrating both ends of the hollow fiber membrane in the axial direction in layers is formed by a membrane element in which a plurality of gaps are provided adjacent to each other in the vertical direction, and the gap in the axial direction of the membrane bundling body A filtering device is provided, wherein a distal end portion of a diffuser tube for bubbling by ejecting gas toward the front side is exposed, and a proximal end portion of the diffuser tube is detachably connected to an air introduction header. ing.

  In the filtration device of the present invention having the above-described configuration, even if the air diffuser hole of the air diffuser tube is blocked during the filtration process, the blocked air diffuser tube is removed from the air introduction header to remove clogging. Can do. The function can be easily restored simply by inserting and attaching the diffuser after cleaning.

In the filtering device of the present invention, it is preferable that a membrane element is formed by arranging a horizontal section of the membrane focusing body converged in a layer shape into a rectangular shape, and arranging each membrane focusing body in parallel with a gap portion therebetween.
Thereby, a diffuser can be easily arrange | positioned in the space | gap part of an adjacent film | membrane focusing body.

It is preferable that the number of layers of the multiple hollow fiber membranes constituting the membrane focusing body is 2 to 6.
With this configuration, air bubbling acts on almost the entire outer peripheral surface of each film focusing body, and each film focusing body is efficiently swung to remove and remove suspended components deposited on the film surface or between the films. be able to.

The thickness of the multiple hollow fiber membranes constituting the membrane focusing body and the width of the gap between adjacent membrane focusing bodies are preferably 2 mm or more and 20 mm or less.
The thickness of the layer of the hollow fiber membrane and the width of the gap of the adjacent membrane focusing body are appropriately set depending on the properties of the liquid to be treated, but the thickness of the layer is preferably larger than the width of the gap. Or equivalent.

Further, in the filtration device of the present invention, it is preferable that a joint connector that can be inserted, mounted, pulled out and removed by a single operation is interposed in the connection portion between the proximal end portion of the air diffuser and the header for air introduction. .
If comprised in this way, a diffusing pipe can be pulled out and detached from the header for air introduction by one operation (one touch), and clogging can be cleaned. Then, after cleaning, the function can be easily restored simply by inserting and attaching the diffuser tube with one touch.

It is preferable that the distal end portion of the air diffuser facing the gap portion is configured to be bent downward in the vertical direction.
Thereby, it is possible to prevent the suspended components separated from the membrane by air bubbling cleaning from entering the air diffuser of the air diffuser, and to suppress the blockage of the air diffuser of the air diffuser.

  According to the filtering device of the present invention, the air diffuser is exposed to the gap formed between the adjacent membrane focusing bodies, and bubbling is performed by ejecting gas from the diffusion pipe in the axial direction of the membrane focusing body. Therefore, air bubbles are supplied over the entire gap, and suspended components deposited on the surface of the membrane or between the membranes can be efficiently removed by air bubbling and removed, and the air diffuser of the air diffuser can be blocked. Can be suppressed.

  In addition, since the distal end of the diffuser tube faces the gap formed between adjacent membrane focusing bodies and the proximal end of the diffuser tube is detachably connected to the header for air introduction, even if the diffuser of the diffuser tube is connected. Even if the pores are clogged, the function can be easily restored simply by inserting and attaching after removing the diffusing tube from the air introduction header and removing it to remove clogging. Therefore, the work of exchanging the whole membrane module or lifting the membrane module and taking out the air diffuser and cleaning it as in the prior art becomes unnecessary.

Preferred embodiments of the present invention will be described below with reference to the drawings.
1 to 8 show an embodiment in which the present invention is applied to an immersion type suction filtration apparatus.
The filtration device 10 of this embodiment is configured by immersing a predetermined number of membrane modules 1 in an immersion tank 3 filled with the liquid 2 to be treated. Here, the membrane module 1 has a total of 10 examples in the front and rear rows indicated by reference numerals 1a to 1e and 1f to 1j.

  As shown in FIG. 5 and FIG. 6 (A), the membrane module 1 is composed of seven membranes in this example in which both ends in the axial direction of a plurality of hollow fiber membranes are converged in layers so that the horizontal section is rectangular. The converging bodies 5a to 5g are constituted by the membrane element 5 which is arranged adjacently in parallel. Gaps 7a to 7f are formed between the adjacent film focusing bodies 5a to 5g, respectively. Each of the film converging bodies 5a to 5g is arranged so that its axis is in the vertical direction, and the upper and lower ends thereof are converged and kept in an open state while being kept in an open state by the upper fixing resin 6a and the lower fixing resin 6b. It is fixed in shape. Water collecting members 9a and 9b are attached to the upper and lower fixing resins 6a and 6b via O-rings 8a and 8b, and communicate with upper and lower treatment liquid outlets 11a and 11b. Flange 12a, 12b is bolted to the upper and lower water collecting members 9a, 9b to maintain a liquid-tight state.

  The material of the hollow fiber membrane that forms the membrane focusing bodies 5a to 5g is not particularly limited, but polysulfone resin, polyacrylonitrile, cellulose derivative, polyolefin such as polyethylene and polypropylene, polyvinyl alcohol resin, polysulfone Resins, fluororesins such as polytetrafluoroethylene and polyvinylidene fluoride, and materials made of various materials such as polyamide, polyester, polymethacrylate, polyacrylate and the like can be used. Further, a copolymer of these resins or a resin in which a substituent is introduced may be used, or a resin obtained by mixing two or more kinds of resins may be used.

  The upper and lower fixing resins 6a and 6b are usually used by curing a liquid resin such as an epoxy resin, an unsaturated polyester resin, or a polyurethane resin. The upper and lower water collecting members 9a and 9b may be made of a material having mechanical strength and durability. For example, polycarbonate, polysulfone, polyolefin, polyvinyl chloride, acrylic resin, ABS resin, modified resin The thing by PPE resin etc. can be used.

  As shown in FIGS. 1 to 4, the processing liquid outlets 11a and 11b of the membrane modules 1a, 1f, 1b, 1g,. The processing liquid extraction pipes 13 and 14 communicate with each other. One ends 13a and 14a of the upper and lower processing liquid extraction pipes 13 and 14 are sealed, and the other ends 13b and 14b are integrated on one side and connected from the processing liquid suction pipe 15 to a suction pump 16 with a pressure gauge 16a. ing. An air introduction pipe 17 is erected on the other side of the immersion tank 3 and connected to the blower 18. The air introduction pipe 17 is bent in the vicinity of the lower fixing resin 6b of the membrane module 1, and is sewn between the front and rear membrane modules 1a, 1f, 1b, 1g,..., 1e, 1j as an air introduction header 20. It extends to one side in the immersion tank 3. The lower end portion 17a of the air introduction pipe 17 is sealed, and is TIG welded to one end 14a of the lower processing liquid extraction pipe 14 so as to prevent the lower processing liquid extraction pipe 14 from being cantilevered when the filtration apparatus is installed. doing. Reference numeral 11c is a ball valve provided at the upper end processing station outlet 11a. The filtration device 10 is fixed by attaching the upper hanging metal fittings 10 a and 10 b to predetermined positions in the immersion tank 3.

  At positions on the air introduction header 20 on the line connecting the gap portions 7a to 7f of the membrane focusing bodies 5a to 5g constituting the membrane modules 1a, 1f, 1b, 1g,. 6 joint connectors 21 are attached. The joint connector 21 is directed to the gaps 7a to 7f of the adjacent film focusing bodies 5a to 5g from the coupling portion with the air introduction header 20, and is branched into two directions to form the diffuser tube insertion portions 21a and 21b. It has a T shape (see FIGS. 4 and 7). The diffuser tube 22 is inserted into each of the diffuser tube insertion portions 21a and 21b, and the tip portion thereof faces the lower end side of the gap portions 7a to 7f.

  The operation of the filtration device 10 according to the present embodiment will be described. The liquid 2 to be treated introduced and filled in the immersion tank 3 is permeated through the hollow fiber membranes of the membrane modules 1 by driving the suction pump 16 to be a solid liquid. Separation is performed, and the liquid is recovered as the processing liquid 19 from the processing liquid suction pipe 15.

  When the suspended components deposited on the surfaces of the membrane focusing bodies 5a to 5g or between the membranes are peeled and removed by continuing the membrane filtration, the blower 18 is operated to connect the joint connector 21 from the air introduction pipe 17 and the air introduction header 20. The air introduced through the above becomes air bubbles from the tip of the diffuser tube 22 and rises in the gaps 7a to 7f of the film focusing bodies 5a to 5g, so that efficient air bubbling cleaning is performed. Bubbling may be performed constantly (continuously) or intermittently.

  At this time, since the thin air diffuser is arranged in the gap between adjacent film converging bodies, each film converging body can be arranged with a high density just by providing a space of the width of the air diffuser, and filtration is performed. High performance can be maintained.

  Each of the membrane focusing bodies 5a to 5g constituting the membrane element 5 focuses the hollow fiber membranes in layers so that the horizontal cross section is rectangular. Thereby, the diffuser tube 22 can be easily disposed in the gaps 7a to 7f of the adjacent film focusing bodies 5a to 5g. At this time, it is desirable that the hollow fiber membranes corresponding to the rectangular short sides are arranged in parallel so that the number of layers is 2-6. FIG. 6A shows an example in which the number of layers is three. Thereby, air bubbling acts on almost the entire outer peripheral surface of each film focusing body 5a-5g and on both surfaces of each film focusing body 5a-5g, and each film focusing body is efficiently swung to Alternatively, the suspended components deposited between the films can be peeled off. When the number of layers of the hollow fiber membrane is less than 2, the number of voids 7a to 7f formed between the membrane focusing bodies 5a to 5g also increases, and a large number of air diffusers described later must be provided. It becomes difficult to realize good filtration performance. Moreover, when the number of layers exceeds 6, it becomes difficult to enhance the effect of air bubbling cleaning.

As shown in FIG. 6 (A), the length of the hollow fiber membrane layer corresponding to the long side of the rectangular shape of the membrane focusing bodies 5a to 5g focused in layers so that the horizontal cross section is rectangular is the center portion. The length is gradually shortened toward the end so as to keep a substantially circular shape as a whole.
In the present embodiment, the horizontal layers of the film focusing bodies 5a to 5g converged in layers are rectangular, and the film focusing elements 5a to 5g are arranged in parallel by providing gaps 7a to 7f. An example is shown in which the tip of the air diffuser 22 is exposed to the gaps 7a to 7f. However, as shown in FIG. 6B, the film focusing bodies 5a ′, 5b ′, 5c ′ focused in a layered manner. The membrane cross-sections 5a ′ to 5c ′ are arranged concentrically by providing gap portions 7a, 7b ′, 7c, and 7d ′ to each other to form a membrane element 5 ′. You may face the front-end | tip part of the diffuser tube 22 to -7d '.

Also, in FIG. 6A, the thickness t of the hollow fiber membrane layer corresponding to the rectangular short sides of the membrane focusing bodies 5a to 5g obtained by concentrating the hollow fiber membranes in layers so that the horizontal cross section is rectangular. The width d of the gaps 7a to 7f formed between the film focusing bodies 5a to 5g is 2 mm or more and 20 mm or less, preferably 5 mm or more and 15 mm or less. When the thickness t of the layer and the width d of the void portion are less than 2 mm, the number of the void portions 7a to 7f is increased as in the case of the number of layers of the hollow fiber membrane, thereby realizing good filtration performance. It becomes difficult. On the other hand, when the thickness t of the layer and the width d of the void portion exceed 20 mm, it is difficult to enhance the effect of air bubbling cleaning.
The thickness t of the hollow fiber membrane and the width d of the gap of the adjacent membrane focusing body are appropriately set depending on the properties of the liquid to be treated, but the thickness t of the layer is larger than the width d of the gap. It is preferable, but it may be equivalent.

  As shown in FIG. 6A and FIG. 7, each of the diffuser tubes 22 facing the gaps 7a to 7f of the adjacent film focusing bodies 5a to 5g is a film that is focused in layers so that the horizontal cross section is rectangular. It is desirable to arrange the converging bodies 5a to 5g so that their tip portions face the central positions of the long sides. Thereby, the air bubbles ejected from the air diffuser hole 22a at the tip of the air diffuser 22 can be supplied over the entire space 7a to 7f. The shape of the air diffusion tube 22 may be a straight tube, but it is more desirable to configure the tip portion to be bent downward in the vertical direction as shown in the figure. Thereby, it is possible to prevent the suspended components separated from the film by air bubbling cleaning from entering the air diffuser of the air diffuser tube 22, and to suppress the blockage of the air diffuser hole of the air diffuser tube 22. The material of the air diffuser 22 can be a metal material such as SUS or a hard plastic material such as polyvinyl chloride. In order to make the air diffuser 22 face the gaps 7a to 7f, a protective tube (not shown) is put on the tip of the air diffuser 22 so as not to damage the adjacent film focusing bodies 5a to 5g. It is good to leave.

  The number, arrangement position, arrangement direction, and the like of the diffusing tubes 22 can be set as appropriate. In addition to facing the air gap portions 7a to 7f of the adjacent membrane focusing bodies 5a to 5g, if the air diffusion tube 22 'is arranged between the membrane modules 1a to 1e, the bubbling cleaning is further performed. Can be effective.

Next, the connection between the joint connector 21 and the air diffuser 22 will be described.
As shown in an enlarged view in FIG. 8, the joint connector 21 has a T-shape having a coupling portion 21c with the air introduction header 20 and diffuser tube insertion portions 21a and 21b branched in two directions. . The proximal end portion of the diffuser tube 22 is detachably connected to the diffuser tube insertion portions 21a and 21b.

  A known means is used to attach / detach the diffuser tube 22 to / from the joint connector 21. The basic structure of the joint connector 21 is, in order, from the step portion 23a of the connector body 23 to the diffuser tube insertion portion (opening) 21a in order. A member 24, a back ring 25 that presses and holds the seal member 24, a retaining ring 26 that is an annular thin plate that locks the diffuser tube 22 to prevent it from coming off, and the connector body 23 that retains the back ring 25. And a release ring 28 supported so as to be movable along the collar 27. The retaining ring 26 is held by inserting an outer edge 26b of the retaining ring 26 into an annular groove formed by the back ring 25 and the collar 27, with the inner edge 26a and the outer edge 26b facing away from the opening.

  With the above configuration, the diffuser tube 22 is inserted and attached to the diffuser tube insertion portion 21a of the connector main body 23 with one touch, and in the illustrated state of attachment, the inner edge 26a of the retaining ring 26 is scattered by its spring property. The outer wall of the trachea 22 is locked to prevent it from coming out to the opening side. When pulling out the diffuser tube 22, the release ring 28 is pushed in so that the tip thereof presses the inner edge 26 a of the retaining ring 26 and the engagement with the outer wall of the diffuser tube 22 is released. If the diffusing tube 22 is pulled in this state, it can be easily pulled out and detached with a single touch.

  As described above, in the present embodiment, the distal end portion of the air diffusion tube 22 faces the gap portions 7a to 7f formed between the adjacent film focusing bodies 5a to 5g, and the proximal end portion of the air diffusion tube 22 is formed. Is detachably connected to the joint connector 21 attached to the air introduction header 20, so even if the air diffuser 22 a at the tip of the air diffuser 22 is blocked during the filtration process, Can be removed from the joint connector 21 to remove the clogging. The function can be easily restored by simply inserting and attaching the diffuser after cleaning. Further, when all the diffuser tubes 22 are to be cleaned, all the distal ends of the diffuser tubes 22 facing the void portions 7a to 7f of the membrane focusing bodies 5a to 5g are removed from the void portions 7a to 7f, and the diffuser tubes are removed. The base end portion of 22 may be pulled out of the joint connector 21 one by one, and cleaning work is easy. The insertion and installation of the diffuser tube 22 after cleaning is completed with one touch. In this way, it is possible to efficiently attach / detach / clean the diffuser tube.

  Therefore, the membrane module as a whole, despite the fact that the membrane module itself has sufficient durability and operability, despite the problems with conventional devices that provide air diffuser holes at one end (potting part) of the membrane module. It is economical because it can solve the problem of having to exchange. Also, there is a problem with the conventional device that diffuses air from a diffuser installed separately from the membrane module below the membrane module, that is, the entire membrane module is lifted and then the diffuser is taken out of the immersion tank and replaced. In addition, the problem that it is necessary to clean the clogging of the diffuser holes after draining all the water in the immersion tank can be solved, and the work of replacement and cleaning becomes unnecessary.

  In the above embodiment, an example of an embodiment in which the present invention is applied to an immersion type suction filtration apparatus has been described. However, the same effect can be naturally obtained even when applied to an external pressure filtration apparatus.

  Using 945 expanded PTFE hollow fibers having an inner diameter of 1 mm, an outer diameter of 2 mm, a porosity of 75%, a hole diameter of 2 μm, and an effective length of 1530 mm, seven membrane focusing bodies 5 (5a to 5A) having a rectangular cross section shown in FIG. 5g) was arranged in a pattern, and after inserting into a sleeve made of ABS resin with a groove in advance, the upper and lower end portions were fixed with a fixing resin (epoxy resin) while maintaining the open state, and the membrane module 1 was produced. . The number of layers of the hollow fiber membrane was 3, the thickness of the layer was 6 mm, and the width of each of the gaps 7a to 7f formed in the adjacent membrane focusing body was 5 mm. The membrane focusing bodies 5a and 5g were 118 hollow fibers, the membrane focusing bodies 5b and 5f were 135, the membrane focusing bodies 5c and 5e were 145, and the membrane focusing body 5d was 149 hollow fibers.

  This single membrane module 1 is installed in the vertical direction in the immersion tank, and the bubbling is performed with the air diffuser facing the gap between the adjacent membrane focusing bodies, and the suction pump with a pressure gauge is driven to maintain the constant flow rate. Suction filtration by operation was performed. As the liquid to be treated, wastewater containing microbial cells targeted by the membrane separation activated sludge method (10000 mg / L) was used.

(Comparative Example 1)
In the same ABS sleeve as in Example 1, the same hollow fiber was used, the hollow fibers were closely packed with the same filling rate, and the upper end and the lower end were fixed resin (epoxy) while maintaining the open state. The membrane module was manufactured by fixing with a resin. The number of films was 1500.
This single membrane module was installed in the vertical direction in the immersion tank, and bubbling was performed by blowing out gas from the diffuser holes of the diffuser plate installed below the membrane module, and suction filtration was performed. Other conditions were the same as in Example 1.

(Filtration conditions)
Set filtration flow rate: 6m ³ / day
Water temperature: 20-28 ° C (graph shows 25 ° C correction value)
Reverse cleaning: Frequency once / 10 minutes, pressure 200 kPa, time 30 seconds Aeration (Bubbling): Frequency Always (20 L / min)

FIG. 9 shows the results of Example 1 and Comparative Example 1, and shows the relationship between the number of filtration days and the membrane filtration pressure. In Example 1, although the membrane filtration pressure slightly increased in the initial stage of filtration, the filtration days became almost constant from about 20 days, and it was confirmed that good filtration performance could be sustained.
On the other hand, in Comparative Example 1, the value of the membrane filtration pressure continued to increase with the passage of the filtration days, the recovery of the filtration performance was not observed, and the filtration performance could not be maintained, so the filtration life was shortened.

  The filtration device of the present invention can efficiently remove and remove suspended components deposited on the membrane surface or between the membranes by air bubbling, and even if the diffusion holes of the diffusion tube are blocked, Since the function can be restored, it is optimal not only for the water purification field but also for the sewage field targeted by the membrane separation activated sludge method. It can also be applied to the treatment fields such as industrial wastewater and livestock wastewater.

It is a front view of the filtration apparatus which shows one example of embodiment of this invention. It is a top view of FIG. It is sectional drawing cut | disconnected by the AA line of FIG. 1 and looked at the arrow direction. It is sectional drawing cut | disconnected by the BB line of FIG. 1 and looked at the arrow direction. Expanded sectional view of the membrane module of the present embodiment (A) and (B) are horizontal sectional views of the membrane element of this embodiment. FIG. 5 is a partially enlarged view of FIG. 4. It is a partially cutaway front view of the joint connector of this embodiment. It is a figure which shows the relationship between the filtration days of Example 1 and Comparative Example 1, and a membrane filtration pressure. It is drawing which shows a prior art example. It is drawing which shows another prior art example. It is drawing which shows another prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Membrane module 3 Immersion tank 5 Membrane element 5a-5g Membrane focusing body 7a-7f Cavity 10 Filtration device 17 Air introduction pipe 20 Air introduction header 21 Joint connector 21a, 21b Air diffuser insertion part 22 Air diffuser

Claims (7)

A filtration device for performing solid-liquid separation by allowing a liquid to be treated containing a suspended component to pass through a membrane module for immersion type suction filtration or external pressure filtration,
The membrane module is constituted by a membrane element formed by concentrating a plurality of hollow fiber membranes in the axial direction on both ends in the axial direction in a layered manner so that a plurality of gap portions are provided adjacent to each other in the vertical direction. Further, a filtration device characterized by facing a diffuser tube for bubbling by ejecting gas in the axial direction of the membrane focusing body. A filtration device for performing solid-liquid separation by allowing a liquid to be treated containing a suspended component to pass through a membrane module for immersion type suction filtration or external pressure filtration,
The membrane module is composed of membrane elements formed by concentrating a plurality of hollow fiber membranes in axial direction on both ends in the axial direction in a layered manner and providing a plurality of adjacent gaps in the vertical direction. In addition, the distal end portion of the diffuser tube for bubbling by ejecting gas in the axial direction of the membrane focusing body is faced, and the proximal end portion of the diffuser tube is detachably connected to the header for air introduction A filtration device.   The filtration device according to claim 1 or 2, wherein a membrane element is formed by arranging a horizontal cross section of the membrane focusing body converged in a layer shape into a rectangular shape, and arranging each membrane focusing body in parallel with a gap portion therebetween.   The filtration device according to any one of claims 1 to 3, wherein the number of layers of the multiple hollow fiber membranes constituting the membrane focusing body is 2 to 6.   The thickness of the layer of many hollow fiber membranes which comprise the said membrane focusing body, and the width | variety of the space | gap part of an adjacent membrane focusing body were 2 mm or more and 20 mm or less, The any one of Claims 1 thru | or 4 characterized by the above-mentioned. Filtration equipment.   4. A joint connector that can be inserted, mounted, pulled out and removed by a single operation is connected to a connecting portion between a base end portion of the air diffuser and an air introduction header. The filtration apparatus as described in.   The filtration device according to any one of claims 1 to 6, wherein a distal end portion of the air diffuser facing the gap portion is bent downward in the vertical direction.

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