JP3386169B2 - Suspended external pressure type hollow fiber membrane module - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a suspension type external pressure type hollow fiber membrane module.

[0002]

2. Description of the Related Art In a hollow fiber membrane module, the membrane area per unit volume can be increased, which is advantageous for downsizing the membrane module. Particularly, in the external pressure type hollow fiber membrane module, By using it as a mold, it is possible to reduce the occupied area for installation, and in combination with the downsizing of the membrane module, it is possible to reduce the site cost.

In a membrane module, a decrease in filtration rate due to clogging of the membrane due to the progress of use is unavoidable, and it is necessary to wash the membrane at appropriate times to recover the filtration rate. As a cleaning method for modules,
A so-called air scrubbing method is known in which air is introduced from below in the presence of a stock solution, and a hollow fiber membrane is vibrated to remove and remove deposits on the membrane surface.

FIG. 4A shows the main part of a known suspension type external pressure type hollow fiber membrane module (Japanese Patent Laid-Open No. 64-67207) capable of air scrubbing cleaning. In FIG. 4A, reference numeral 1'denotes an external pressure type membrane module unit, which houses a hollow fiber membrane bundle 12 'and a filtrate collecting pipe 13' in a cylindrical case 11 ', and a central hole 141. A resin partition wall 14 'having' is cast at both ends of the tubular case (however, there is no central hole in the upper resin partition wall of the uppermost unit 1a '), and each end of the hollow fiber membrane and the collection are collected. Each end of the water pipe is opened on the surface of the resin partition wall.

Reference numeral 2'denotes a joining member, and as shown in FIG. 4 (b) (cross-sectional view), it is screwed up and down to form connection ports 21 ', 2'.
1'is provided with a partition wall portion 22 'in the middle, and the partition wall portion 22' is provided with a central hole 23 'corresponding to the resin partition wall central hole 141' of the unit, and on the upper and lower surfaces of the partition wall portion 22 '. Is an annular groove 24 'surrounding the central hole 23' and the annular groove 2 '
An O-ring mounting groove 25 'that surrounds 4'and an O-ring mounting groove 26' that surrounds the central hole 23 'are provided.
4'is provided with several through holes 27 '.

With this joining member 2 ', the upper and lower membrane module units 1', 1'are screwed together at the ends of the tubular case, and the tubular case 11 'of both units 1', 1 '. The inside is communicated by a series of central holes 141'-23'-141 ', and the O-ring 31' seals between this communication hole (141'-23'-141 ') and the filtrate side of the unit connection body. An O-ring 32 'seals between the filtered liquid side of the unit connection body and the outside of the cylindrical case.

In FIG. 4A, reference numeral 4'denotes a terminal member screwed to the lower end of the cylindrical case of the lowermost unit 1b 'and has a central hole 41' and an annular groove 42 '. , The central hole 41 'and the central hole 14 of the unit lower resin partition wall 14b'
1b 'is communicated, and the O-ring 42' seals between the communication hole and the filtrate side of the module,
O between the filtrate side of the module and the outside of the cylindrical case of the module.
It is sealed by a ring 43 '.

In FIG. 4 (a), 5'denotes a partition plate between the raw liquid chamber and the filtered liquid chamber in the filtration tower, and the external pressure type hollow fiber membrane module constituted by connecting the above units is the uppermost stage. The suspension member 51 ′ of the unit 1a ′ is suspended and supported by the partition plate, and the hollow fiber membrane and the water collecting pipe of the unit are connected to the filtrate chamber 52 ′.

In the above hanging type external pressure type hollow fiber membrane module, the pressurized stock solution in the stock solution chamber of the filtration tower is pressed into the tubular case of each unit from the stock solution inlet of the case to form a hollow fiber. After being filtered by the membrane, the filtrate in the hollow fiber membrane is diverted in both the upper and lower directions, and this diverted filtrate flows upward with a low resistance by the water collection pipe through the annular groove and the through hole of the joining member, Although it is mechanically a series connection of membrane module units, it is equivalent to parallel connection in terms of flow path,
The resistance of the filtrate can be reduced, and efficient filtration processing can be guaranteed.

In order to perform air scrubbing cleaning of this suspension type external pressure type hollow fiber membrane module, an air introduction pipe disposed directly below the central case of the end member of the lowermost unit into a cylindrical case. The air from the unit is sent, and the supplied air is sent to the upper unit through the communication hole between the units, and the rising gas-liquid mixed flow vibrates the hollow fiber membrane of each unit, and this vibration causes the film adhered matter to be removed. It is peeled off.

[0011]

In this air scrubbing cleaning, the gas-liquid mixed flow is throttled as it passes through the communication holes between the units, and is further blown out into the cylindrical case of the upper unit, and then, Since a part of the gas-liquid mixed flow is discharged from the raw liquid inlet of the cylindrical case while rising in the cylindrical case, the flow pattern of the gas-liquid mixed flow is complicated. , Not only axial flow in the module but also circumferential flow exists.

Therefore, during air scrubbing cleaning, generation of force in the circumferential direction of the module is unavoidable, and torsional moment is inevitably generated under the generation of this circumferential force. In the suspension type external pressure type hollow fiber membrane module of FIG. 4 (a) in which the module units are screwed and connected by a joining member, depending on the direction of the twisting moment, that is, the direction of the twisting moment. Is a joining member
2 ′ and the end of the membrane module unit are screwed together
In the case of the direction opposite to the direction , looseness is likely to occur in the screwed state of the joint, and under such a condition, the tightening force of the O-rings 31 ', 32', etc. is reduced, and there is concern that the filtrate may be contaminated by the stock solution. It Further, in the joining member 2 ', the membrane module unit is
Twisting rigidity (twisted cross section secondary maume compared to knit 1 '
(Entry x twist Young's modulus) is considerably large,
The joint is not applicable to the twisting moment during rubbing cleaning
It is flexible and difficult to follow the twist, and twist mode at the joint
You can hardly expect the absorption of ment. Further, the air disc
The effect of bending moment is inevitable during rubbing cleaning.
However, the joint part 2 ′ undergoes bending at the joint part.
And membrane module unit 1 ', resin partition wall 14' and joint
Bending between the end faces facing the material 2 is about to be opened on the bending pull side.
Therefore, deterioration of the sealability of the O-rings 31 'and 32' is suspended.
Be reminded. Further, in the joining member 2 ′, the membrane module
Flexural rigidity (bending cross section secondary momen compared to Unit 1 '
(To x Young's modulus) is considerably large,
The joint is inflexible against bending moment during cleaning.
Since it is difficult to follow bending, it absorbs bending moment at the joint.
I can hardly expect the income.

An object of the present invention, even if the air scrubbing washing, membranes module - can stably hold a connection state between Ruyunitto, timely, a more good <br/> good filtration efficiency to perform air scrubbing washing An object is to provide a suspended external pressure type hollow fiber membrane module that can be operated.

[0014]

SUMMARY OF THE INVENTION A suspending external pressure type hollow fiber membrane module of the present invention has a hollow case containing a hollow fiber membrane bundle and a water collecting pipe, and a resin partition wall having a through hole. A plurality of external pressure type membrane module units, which are provided at both ends in the tubular case, have at least one end of the hollow fiber membrane opened on the surface of the resin partition and each end of the water collection pipe is opened on the surface of the resin partition, respectively. disposed in the direction, cylindrical Ke of the upper and lower units to each other - is disposed a connecting tube between the scan end, the connecting tube and the tubular Ke - either a scan end portion
A configuration is also characterized by being communicated with the insertion of the connecting tube of the through-holes of the resin partition walls of the two units via the O-ring as well as joined to non-rotating with respect to the direction of twisting moment, the bottom unit The air inlet pipe is inserted into the through hole of the lower resin partition wall through the O-ring, and the cap is arranged at the lower end of the cylindrical case of the unit, and either the cap or the cylindrical case is inserted. Is not affected by the twisting moment in the direction of
The air inlet pipe can be pulled out in a liquid-tight manner from the cap while being joined to the roll .

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an explanatory view showing an embodiment of the present invention. 2A, FIG. 2B, and FIG. 2C show enlarged views of B, C, and C in the dotted-line frame of FIG. 1, respectively.

In FIG. 1, reference numeral 1 denotes an external pressure type hollow fiber membrane module unit, in which a hollow fiber membrane bundle 12 and a filtrate are contained in a cylindrical case 11 (made of plastic) having a plurality of stock solution inflow holes 111. A water collecting pipe 13 (made of plastic) is housed, and resin partition walls 14 having a through hole 141 in the center are cast at both ends in the cylindrical case 11, so that each end of the hollow fiber membrane and each end of the water collecting pipe are An opening is formed in the surface of each resin partition. However, no through hole is provided in the upper resin partition wall 14a of the uppermost unit 1a.

Reference numeral 2 is a connection tube (made of plastic, preferably made of the same material as the cylindrical case 11).
As shown in FIG. 2A, the tubular case ends 110, 110 of the units 1, 1 above and below each other.
The connection tube 2 and the tubular case end portion 110 are inserted between the connection case 2 and the cylindrical case end portion 110 with respect to a twisting moment in any direction.
Are also non-rotatably bonded by heat fusion or adhesive 21. The connection tube 2 and the tubular case end 110 may be screwed together, and then heat-sealed or bonded by the adhesive 21. In addition, an O-ring 24 is attached between the step surface 23 in the end portion of the connecting cylinder and the cylindrical case end surface 112 to prevent impact.
It can also be absorbed .

In FIG. 1, reference numeral 3 is a connecting pipe (made of plastic), and as shown in FIG. 2A, through holes of the resin partition walls 14 of the upper and lower units 1 and 1, respectively. The connecting pipe 3 is inserted across 141 and 141.
The O-ring 31 seals between the through hole 141 and each of the through holes 141.

In FIG. 1, 4 is a cap (made of plastic, preferably made of the same material as the cylindrical case 11), as shown in FIG. 2B. The lower end 11 of the cylindrical case of the lowermost unit 1b
3, the cap 4 and the lower end 11 of the tubular case
3 and 3 are joined by heat fusion or an adhesive 41. In addition to this joining, the lower end 113 of the tubular case and the cap 4 can be screwed together 42, and an O-ring 43 can be mounted between the inner surface of the cap and the end of the tubular case. You can also Reference numeral 44 is a through hole provided in the cap bottom wall 40, and 45 is a skirt provided around the cap bottom wall.

In FIG. 1, numeral 5 is an air inlet pipe, and as shown in FIG. 2B, the lowermost unit 1
It is inserted into the through hole of the lower resin partition wall 14b of b through the O-ring 51, and is pulled out in a liquid-tight manner from the cap bottom wall 40 through the O-ring 52.

In FIG. 1, 6 is a hanging member, and FIG.
As shown in (c) of FIG. 5, a flange 62 is provided at the upper end of the tubular portion 61, and the tubular portion 61 is a tubular case of the uppermost unit 1a.
It is inserted into the upper end portion 114 of the sleeve, and the cylindrical portion 61 and the upper end portion 114 of the cylindrical case are joined by heat fusion or an adhesive 63. In addition to this joining, the tubular portion 6 of the hanging member 6
1 and the tubular case upper end 114 can be screwed together 64, and an O-ring 65 can be mounted between the inner surface of the tubular part and the end of the tubular case. Reference numeral 114 denotes an air vent hole provided in the cylindrical case of the uppermost unit 1a in the vicinity of the upper resin partition 14a.

In FIGS. 1 and 2 (a) and (b), e is a water collecting chamber surrounded by a connecting cylinder or cap, a connecting pipe or an air inlet pipe, and a resin partition wall.

As shown in FIG. 3, the suspended external pressure type hollow fiber membrane module of the present invention is housed in a filtration tower 7, and is suspended by a suspending member 6 of the uppermost unit 1a via a O-ring 72 on a partition plate 71. Is suspended and supported. In FIG. 3, reference numerals 73 and 74 denote a filtrate chamber and a stock solution chamber partitioned by the partition plate 71, 81 denotes a lower air introducing pipe, and 82 denotes an upper air introducing pipe.

In order to filter raw water by the suspension type external pressure type hollow fiber membrane module of the present invention, raw water is press-fitted into the raw water chamber 74 from the raw water supply port 91 in FIG. After filtration, the filtrate is collected in the filtrate chamber 73, and then taken out from the filtrate outlet pipe 92.

In order to perform air scrubbing cleaning of the suspended external pressure type hollow fiber membrane module of the present invention, in FIG. 1 and FIG. 3, with the stock solution filled in the stock solution chamber 74, the lower air introducing pipe 81 Air is jetted into the skirt 45 of the cap 4, and the air is sent into the cylindrical case 11 of the lowermost unit 1b through the air inlet pipe 5.

In the presence of the undiluted solution, this inflowing air rises as a gas-liquid mixed flow and is throttled as it passes through the connecting pipe 3 between the units 1 and 1, and this throttling flow is a cylindrical case above it. -Su 11
The hollow fiber membrane 12 is vibrated by the disturbance and the upward flow in the cylindrical case when blown out into the inside, and the film-adhering substance is separated by this vibration, and the cylindrical case 11 of the uppermost unit 1a. Air is released from the air vent hole 14.

In this case, it is inevitable that the gas-liquid mixed flow will flow out from the raw liquid inflow hole 111 of the cylindrical case 11 of each unit, so that the gas-liquid mixed flow is twisted in the circumferential direction with respect to the module. Moment works. Further, the air blown from the lower air introduction pipe 81 pushes up the cap 4, and a bending moment acts.

However, the suspension type external pressure type hollow of the present invention
In the thread film module, the external joint member and the internal communication part
For the conventional example in which these are integrated to separate the materials
Compared to this, the joint part can be made flexible, and during air scrubbing cleaning
The joint is made to follow the twist and bending that occur in the
It is possible to reduce the twisting reaction force and bending reaction force at the joint.
Can . In addition, since the connection tube and the end of each tubular case of each membrane module unit are joined non-rotatably against the torsion moment in any direction, they are joined only by screwing according to the conventional example. Unlike in the case of doing so, it is possible to eliminate the fear of loosening the joint portion due to the direction of the twisting moment during the air scrubbing, and thus the detachment fear. Furthermore, the connection
Between the tube and each membrane module unit tubular case end and
Between the connecting tube and the through hole of the resin partition of the membrane module unit
It is only necessary to seal the
Since it does not require a seal between opposite end faces,
The seal can be stably held against bending that acts on the parts.
It

Therefore, in the suspended external pressure type hollow fiber membrane module of the present invention, the joint can be stably held even when strongly air scrubbing washed, and the leakage of the undiluted solution to the filtrate side can be prevented. The filtration can continue.

The cleaning of the module of the present invention is performed by the above-mentioned air scrubbing cleaning and the upper air introducing pipe 8 in FIG.
It is preferable to use in combination with backwashing in which the filtrate in the filtrate chamber is pressed into the hollow fiber membrane by air pressure injection from 2.

In the above embodiment of the present invention, the ends of the hollow fiber membrane are opened on the surfaces of the resin partition walls above and below the unit, that is, both ends of the hollow fiber membrane are opened. If the length is short, only one end may be opened.
Further, one through hole is provided in the center of the resin partition wall, and the inside of the cylindrical case between the upper and lower units is communicated with each other by one connecting pipe. However, depending on the arrangement of the water collecting pipe of the unit, The through hole is provided at a position displaced from the center of the resin partition wall, or a plurality of through holes are provided, and the tubular case between the units is provided.
It is also possible to connect the inside of the chamber with a plurality of connecting pipes.

[0032]

The suspended external pressure type hollow fiber membrane module of the present invention
The structure is as described above, and by the strong air scrubbing cleaning, even if the suspension-supported multi-stage connected hollow fiber membrane module is twisted or bent, the connected state and the sealed state of the connection part can be maintained. It can be held stably, and efficient and efficient air scrubbing cleaning can ensure efficient filtration processing.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an embodiment of the present invention.

FIG. 2 (a) is an enlarged view in a dotted line frame a in FIG.
2B shows an enlarged view inside the dotted line frame B in FIG. 1, and FIG. 2C shows an enlarged view inside the dotted line frame C in FIG.

FIG. 3 is an explanatory view showing a usage state of the suspension type external pressure type hollow fiber membrane module of the present invention.

4 (A) is an explanatory view showing a conventional example, and FIG. 4 (B) is a sectional view showing a joining member used in FIG. 4 (A).

[Explanation of symbols]

1 External pressure type membrane module unit 11 cylindrical case 12 Hollow fiber membrane bundle 13 Water collection pipe 14 resin partition 141 through hole 2 connection tube 21 Heat fusion or adhesive joints 3 connecting pipe 31 O-ring 4 cap 5 Air inlet pipe 52 O-ring

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-64-67207 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B01D 63/04

Claims (2)

(57) [Claims] 1. A hollow fiber membrane bundle and a water collecting pipe are housed in a tubular case, and resin partition walls having through holes are provided at both ends of the tubular case, and at least one end of the hollow fiber membrane is provided. On the surface of the resin partition wall, a plurality of external pressure type membrane module units having the ends of the water collection pipe opened respectively on the surface of the resin partition wall are arranged in the vertical direction, and the cylindrical casings of the membrane module units above and below each other are arranged. disposed the connecting tube between the ends, the connecting tube and the respective tubular Ke - resins of both units together also contact <br/> if the non-rotating relative to the moment twisting the scan end portion of either direction suspended, external pressure type hollow fiber membrane module is characterized in that communicating with the insertion of the connecting tube of the through-hole of the partition wall through an O-ring - le. 2. An air inlet pipe is inserted through an O ring into a through hole of a resin partition wall at the lower end of the lowermost membrane module unit,
A cap is arranged at the lower end of the cylindrical case of the unit, and the cap and the cylindrical case are twisted in either direction.
2. The suspension type external pressure type hollow fiber membrane module according to claim 1, wherein said air inlet pipe is pulled out liquid-tightly from the cap while it is joined non-rotatably to the chamber.