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WO1998016297A1 - Dispositif de filtration a tubes filtrants a extremites ouvertes - Google Patents

Dispositif de filtration a tubes filtrants a extremites ouvertes Download PDF

Info

Publication number
WO1998016297A1
WO1998016297A1 PCT/GB1997/002700 GB9702700W WO9816297A1 WO 1998016297 A1 WO1998016297 A1 WO 1998016297A1 GB 9702700 W GB9702700 W GB 9702700W WO 9816297 A1 WO9816297 A1 WO 9816297A1
Authority
WO
WIPO (PCT)
Prior art keywords
filter
tube
tubes
bundle
fluid
Prior art date
Application number
PCT/GB1997/002700
Other languages
English (en)
Inventor
Nicholas Iain Powell
Paul Martin Gallagher
Peter Towsend Cardew
Joseph Patrick Hannon
Original Assignee
Usf Limited
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Usf Limited filed Critical Usf Limited
Priority to EP97944959A priority Critical patent/EP0946253A1/fr
Priority to AU46287/97A priority patent/AU4628797A/en
Publication of WO1998016297A1 publication Critical patent/WO1998016297A1/fr

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
    • B01D29/11—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with bag, cage, hose, tube, sleeve or like filtering elements
    • B01D29/13—Supported filter elements
    • B01D29/15—Supported filter elements arranged for inward flow filtration
    • B01D29/17—Supported filter elements arranged for inward flow filtration open-ended the arrival of the mixture to be filtered and the discharge of the concentrated mixture are situated on both opposite sides of the filtering element
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
    • B01D29/50—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with multiple filtering elements, characterised by their mutual disposition
    • B01D29/52—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor with multiple filtering elements, characterised by their mutual disposition in parallel connection
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D29/00—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor
    • B01D29/88—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor having feed or discharge devices
    • B01D29/90—Filters with filtering elements stationary during filtration, e.g. pressure or suction filters, not covered by groups B01D24/00 - B01D27/00; Filtering elements therefor having feed or discharge devices for feeding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
    • B01D46/66—Regeneration of the filtering material or filter elements inside the filter
    • B01D46/70—Regeneration of the filtering material or filter elements inside the filter by acting counter-currently on the filtering surface, e.g. by flushing on the non-cake side of the filter
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D63/00—Apparatus in general for separation processes using semi-permeable membranes
    • B01D63/06—Tubular membrane modules
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D65/00—Accessories or auxiliary operations, in general, for separation processes or apparatus using semi-permeable membranes
    • B01D65/02—Membrane cleaning or sterilisation ; Membrane regeneration
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2313/00—Details relating to membrane modules or apparatus
    • B01D2313/10—Specific supply elements
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2321/00—Details relating to membrane cleaning, regeneration, sterilization or to the prevention of fouling
    • B01D2321/04—Backflushing

Definitions

  • the present invention relates to a filter.
  • Filters which comprise a bundle of open-ended filter tubes housed within and extending axially along the length of a support tube, seals being arranged at each end of the support tube such that the filter tubes extend through the seals.
  • the seals prevent axial flow of fluid through the ends of the support tube except through the filter tube.
  • a fluid to be filtered is delivered to the space defined within the support tube between the seals and through which the filter tubes extend. Filtrate which has passed through the walls of the filter tubes flows to the ends of the support tube through the seals.
  • Retentate is either retained within the support tube, if the system is being operated in "dead-end" mode, or is at least partially flushed from the support tube by maintaining a steady flow of the fluid to be filtered through the support tube. This can be achieved by delivering the fluid to a support tube inlet and ensuring that the flow is sufficient to maintain a substantial flow out of the support tube through an outlet.
  • the maximum throughput of a filter is dictated by the available surface area of the filter tubes. Manufacturing filters from bundles of filter tubes as described above ensures a relatively high surface area in a relatively low volume structure. When a filter is first used, substantially all of the surface area of the filter tubes is available, but as particles build up on the filter tubes the throughput of the filter decreases.
  • the fluid to be filtered is fed into the space within the support tube around the filter tube bundle through an opening in the support tube wall.
  • the filter tube bundle is not tightly packed within the support tube as to achieve tight packing would be very difficult in terms of manufacture.
  • Simply feeding fluid to be filtered into the space around the filter tube bundle initially achieves good fluid distribution as the fluid can flow axially through the space between the radially outer filter tubes and the surrounding support tube. As particles build up on the filter tubes however there is a tendency for the particles to block the spaces between adjacent filter tubes in the outer portions of the bundle and as a result the throughput falls relatively rapidly as particles build up.
  • a filter comprising a bundle of open-ended filter tubes housed within and extending axially along the length of a support tube, seals arranged at each end of the support tube such that the filter tubes extend therethrough, the seals preventing axial flow of fluid through the ends of the support tube except through the filter tubes, and at least one conduit communicating with the interior of the support tube between the seals to deliver fluid to or remove fluid from the space defined within the support tube around the filter tubes, wherein the said at least one conduit is connected to at least one passageway extending through the bundle of filter tubes and opening into spaced regions of the filter tube bundle, the spaced regions being distributed such that the filter may be backwashed in a manner which establishes a flow within the said space which is predominantly axial.
  • the term "predominantly axial" is used in the present application in the sense that flow at all but limited and generally peripheral regions of the filter tube bundle is in a direction with an axial component towards the nearest adjacent outlet for backwash fluid. Generally the axial flow will be directed towards only one end of the filter support tube. It has been found that particles distributed in the space defined within the bundle outside the individual filter tubes can be efficiently dislodged by establishing a flow through the bundle which is generally in the axial direction. A substantial proportion of this flow may be through an annular space which is generally defined outside the bundle but within the support tube. The required axial flow can be achieved either by distributing fluid flow passageways in an appropriate manner, or by a combination of fluid flow passageway distribution and control of hydrodynamic pressure occurring during the backwashing process.
  • the backwashing process may be implemented only by pumping filtrate radially outwards through the walls of the filter tubes, but may also include pumping flushing fluid through the bundle between the filter tubes.
  • the passageway may open into radially and circumferentially spaced regions which are located only adjacent one or both of the seals.
  • additional flushing fluid may be pumped into the one network and out of the other network.
  • the flow of fluid is predominantly axial, and the velocity of flow through substantially all of the bundle is sufficient to displace particles from the filter tubes.
  • the filter can as a result be regenerated in a relatively efficient manner.
  • the passageways which distribute fluid to be filtered to the filter bundle may be defined by a plurality of radially extending tubes the walls of which define openings communicating with spaces between the filter tubes.
  • Some of the radially extending tubes may be supported at their radially inner ends by a support member that extends axially through the filter tube bundle. Such a structure is convenient to provide support for the filter bundle during the insertion of the filter bundle into the support tube.
  • Further radially extending tubes may be located between each pair of the tubes which are supported by the axial support member.
  • the support member itself may support radially extending members distributed along its length to provide further support for the filter tube bundle.
  • the said at least one passageway may be defined by at least one distribution tube extending axially through a central portion of the filter tube bundle, the distribution tube having a wall defining a plurality of apertures opening radially outwards into axially and circumferentially spaced portions of the bundle, and the distribution tube having a length and internal diameter such that backwashing establishes a substantial pressure gradient along the length of the distribution tube.
  • Further distribution tubes may be located adjacent at least one end of the filter tube bundle, the further distribution tubes communicating with the axially- extending distribution tube and opening into radially spaced regions of the filter tube bundle.
  • the axially extending distribution tube may support radially extending members distributed along its length to provide support for the filter tube bundle, but it will be appreciated that these radially extending members will not define fluid distribution passageways communicating with the spaces between the filter tubes.
  • the invention also provides a method for backwashing a filter comprising a bundle of open ended filter tubes housed within and extending axially along the length of a support tube, seals arranged at each end of the support tube such that the filter tubes extend therethrough, the seals preventing axial flow of fluid through the ends of the support tube except through the filter tubes, and at least one conduit communicating with the interior of the support tube between the seals to deliver fluid to or remove fluid from the space defined within the support tube around the filter tubes, wherein the filter tube bundle is backwashed by pumping filtrate radially outwards through the walls of the filter tubes and establishing a flow within the said space which is predominantly axial.
  • Figure 1 is a schematic partially cut-away illustration of a known filter structure
  • Figure 2 is a section through one end of a first embodiment of the invention
  • Figure 3 is a section on the line 3-3 of Figure 2, showing the position of the section of Figure 2 by line 2-2;
  • Figure 4 is an axial section through a second embodiment of the present invention.
  • Figure 5 is an enlarged sectional view through an axially extending fluid distribution tube of the embodiment of Figure 4;
  • Figure 6 is a partly cut-away side view of a third embodiment of the invention.
  • Figure 7 is a perspective view of the partly cut-away end of the filter shown in Figure 6.
  • the illustrated conventional structure comprises an outer support tube 1, a bundle of filter tubes 2 extending axially along the length of the support tube, and seals 3 adjacent each end of the support tube.
  • Each of the filter tubes 2 extends through both of the seals 3.
  • the seals 3, which may be formed from for example epoxy resin, are effective to prevent flow of fluid through the ends of the support tube 1 except through the filter tubes 2.
  • An inlet port 4 delivers fluid to be filtered to the space defined within the tube 1 around the filter tubes 2.
  • An outlet port 5 enables a continuous flow of the fluid to be filtered to be established through the structure, that flow being effective to flush some deposited particles from the system.
  • the illustrated first embodiment of the invention does not distribute flow through an axially extending tube but rather distributes flow only to the two ends of the structure.
  • the inlet port 4 communicates with each of six apertured tubes 9 that penetrate the support tube 1 and are supported at their radially inner ends by a solid or tubular support rod 10.
  • the inlet port 4 also communicates with six shorter apertured tubes 11 which project about halfway towards the rod 10.
  • the outlet port 5 is connected to an array of apertured tubes identical to those associated with the inlet port 4.
  • the filter tube bundle fills the spaces between the apertures tubes 9 and 11 and the support rod 10.
  • the support rod does not act as a fluid distribution passageway but simply acts as a support for the filter tube bundle and the radial apertured tubes.
  • the rod 10 may support radial arms similar to the secondary tubes 8 of Figure 1, but those radial arms do not define fluid distribution passageways. Accordingly in the arrangement of Figures 2 and 3, the primary fluid distribution arrangement is not such that fluid to be filtered is distributed throughout the body of the bundle as in the case of Figure 1. In contrast, fluid distribution relies upon passage of the fluid axially between the adjacent tubes of the bundle. This flow in itself is an effective means for dislodging deposited particles. Generally, fluid to be filtered is pumped in through inlet post 4, and fluid which does not pass into the filter tubes exits through the outlet post 5.
  • the filter may operate in dead end mode however, in which case the outlet post 5 would be closed.
  • inlet post 4 is closed, and outlet post 5 is open.
  • Filtrate is pumped into the filter tubes, passes radially outwards through the filter tube walls, and then flows axially towards the outlet post 5.
  • substantially all of the volume of the filter tube bundle is swept by the axial flow and particles lifted from the filter tubes by filtrate passing radially outwards through the walls of the filter tubes are carried axially towards the downstream end of the support tube. Therefore the structure can be more efficiently cleaned as compared with the structure of Figure 1.
  • the rate of flow through the tube 7 is controlled to achieve a desired pressure gradient along the axis of the filter.
  • the tube 7 had an internal diameter of 35mm, a length of 1.35m and a flow rate of more than 3m per second. This was in a 200mm diameter bundle.
  • the filter tube bundle there is a portion of the filter tube bundle in which there is no radial component in the direction of movement of individual particles. This is not a problem providing the axial component is not zero.
  • an axial component will be established throughout the filter tube bundle.
  • the overall axial pressure drop (between the ends of the tube 7) is higher than the radial pressure drop (between the interior of tube 7 and the annulus 13.
  • This third embodiment incorporates features of both the first and second embodiments in that it comprises an axially extending apertured fluid distribution tube 7 that supports and communicates with further radially extending apertured fluid distribution tubes 9.
  • a pressure gradient is established along the tube 7.
  • the tube 7 defines circumferentially extending slots 14, and each tube 9 defines a single radially extending slot 15.
  • the tube 7 also supports radially extending solid arms 16 which serve to support a tube bundle (not shown) through which the tube 7 extends.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Separation Using Semi-Permeable Membranes (AREA)
  • Filtration Of Liquid (AREA)

Abstract

L'invention concerne un filtre sous la forme d'un faisceau de tubes filtrants aux extrémités ouvertes logés dans un tube de support en étant disposés suivant la longueur de celui-ci. Un joint d'étanchéité est prévu à chaque extrémité du tube de support pour que chaque tube filtrant traverse ces joints, les joints empêchant un écoulement axial du fluide aux extrémités du tube de support ailleurs que par les tubes filtrants. Le fluide à filtrer est amené à l'intérieur du tube de support entre les joints. Le fluide à filtrer est réparti aux extrémités du faisceau de tubes filtrants au voisinage des joints et/ou amené à un tube de répartition s'étendant axialement dans le faisceau et s'ouvrant dans la direction radiale sur des portions internes du faisceau. La structure du système de répartition du fluide est telle que durant un lavage à contre-courant, un flux axial s'établit dans la totalité du faisceau de tubes filtrants ou dans une proportion majeure de ceux-ci.
PCT/GB1997/002700 1996-10-12 1997-10-13 Dispositif de filtration a tubes filtrants a extremites ouvertes WO1998016297A1 (fr)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP97944959A EP0946253A1 (fr) 1996-10-12 1997-10-13 Dispositif de filtration a tubes filtrants a extremites ouvertes
AU46287/97A AU4628797A (en) 1996-10-12 1997-10-13 Filtering device with open-ended filter tubes

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GBGB9621339.2A GB9621339D0 (en) 1996-10-12 1996-10-12 Filter
GB9621339.2 1996-10-12

Publications (1)

Publication Number Publication Date
WO1998016297A1 true WO1998016297A1 (fr) 1998-04-23

Family

ID=10801353

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1997/002700 WO1998016297A1 (fr) 1996-10-12 1997-10-13 Dispositif de filtration a tubes filtrants a extremites ouvertes

Country Status (4)

Country Link
EP (1) EP0946253A1 (fr)
AU (1) AU4628797A (fr)
GB (1) GB9621339D0 (fr)
WO (1) WO1998016297A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TWI664010B (zh) * 2018-05-21 2019-07-01 日益電機股份有限公司 過濾機濾芯管定位裝置
WO2019200208A1 (fr) * 2018-04-12 2019-10-17 Aqseptence Group Inc. Tamis d'admission passif à fils profilés perfectionné
CN113926229A (zh) * 2020-07-13 2022-01-14 懿华水处理技术有限责任公司 具有流量扩散器的再生介质过滤容器

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2565842A1 (fr) * 1984-06-13 1985-12-20 Inst Nat Rech Chimique Perfectionnement apporte aux operations d'ultrafiltration et de microfiltration
EP0277411A1 (fr) * 1987-01-22 1988-08-10 The Dow Chemical Company Dispositif et procédé pour séparer des fluides individuels des mélanges de fluides
US4876006A (en) * 1985-10-08 1989-10-24 Ebara Corporation Hollow fiber filter device
JPH03110A (ja) * 1989-05-24 1991-01-07 Ube Ind Ltd 分離膜モジュール
JPH0386219A (ja) * 1989-08-29 1991-04-11 Ube Ind Ltd 中空糸膜モジュール
EP0554567A1 (fr) * 1991-12-31 1993-08-11 Hoechst Celanese Corporation Cartouches de tissu avec membrane à fibres creuses enroulée en spirale et modules avec chicanes d'orientation de flux
WO1996007470A1 (fr) * 1994-09-09 1996-03-14 Memtec America Corporation Nettoyage de membranes a fibres creuses

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2565842A1 (fr) * 1984-06-13 1985-12-20 Inst Nat Rech Chimique Perfectionnement apporte aux operations d'ultrafiltration et de microfiltration
US4876006A (en) * 1985-10-08 1989-10-24 Ebara Corporation Hollow fiber filter device
EP0277411A1 (fr) * 1987-01-22 1988-08-10 The Dow Chemical Company Dispositif et procédé pour séparer des fluides individuels des mélanges de fluides
JPH03110A (ja) * 1989-05-24 1991-01-07 Ube Ind Ltd 分離膜モジュール
JPH0386219A (ja) * 1989-08-29 1991-04-11 Ube Ind Ltd 中空糸膜モジュール
EP0554567A1 (fr) * 1991-12-31 1993-08-11 Hoechst Celanese Corporation Cartouches de tissu avec membrane à fibres creuses enroulée en spirale et modules avec chicanes d'orientation de flux
WO1996007470A1 (fr) * 1994-09-09 1996-03-14 Memtec America Corporation Nettoyage de membranes a fibres creuses

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 015, no. 104 (C - 0814) 13 March 1991 (1991-03-13) *
PATENT ABSTRACTS OF JAPAN vol. 015, no. 259 (C - 0846) 2 July 1991 (1991-07-02) *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2019200208A1 (fr) * 2018-04-12 2019-10-17 Aqseptence Group Inc. Tamis d'admission passif à fils profilés perfectionné
TWI664010B (zh) * 2018-05-21 2019-07-01 日益電機股份有限公司 過濾機濾芯管定位裝置
CN113926229A (zh) * 2020-07-13 2022-01-14 懿华水处理技术有限责任公司 具有流量扩散器的再生介质过滤容器
WO2022015280A1 (fr) * 2020-07-13 2022-01-20 Evoqua Water Technologies Llc Filtre de milieu régénératif avec diffuseur d'écoulement

Also Published As

Publication number Publication date
EP0946253A1 (fr) 1999-10-06
AU4628797A (en) 1998-05-11
GB9621339D0 (en) 1996-12-04

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