GB2130111A - Filtration apparatus - Google Patents
Filtration apparatus Download PDFInfo
- Publication number
- GB2130111A GB2130111A GB08330562A GB8330562A GB2130111A GB 2130111 A GB2130111 A GB 2130111A GB 08330562 A GB08330562 A GB 08330562A GB 8330562 A GB8330562 A GB 8330562A GB 2130111 A GB2130111 A GB 2130111A
- Authority
- GB
- United Kingdom
- Prior art keywords
- filter element
- filtration apparatus
- housing
- tube
- manifold
- Prior art date
- Legal status (The legal status 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 status listed.)
- Withdrawn
Links
- 238000001914 filtration Methods 0.000 title claims description 29
- 239000012530 fluid Substances 0.000 claims abstract description 25
- 238000007789 sealing Methods 0.000 claims description 2
- 239000000706 filtrate Substances 0.000 abstract description 14
- 238000011144 upstream manufacturing Methods 0.000 abstract 2
- 239000007788 liquid Substances 0.000 description 16
- 239000007787 solid Substances 0.000 description 10
- 239000000725 suspension Substances 0.000 description 9
- 238000009295 crossflow filtration Methods 0.000 description 8
- 238000000034 method Methods 0.000 description 6
- 238000010276 construction Methods 0.000 description 4
- 239000000463 material Substances 0.000 description 4
- 239000002245 particle Substances 0.000 description 4
- 230000008021 deposition Effects 0.000 description 3
- 102000004190 Enzymes Human genes 0.000 description 2
- 108090000790 Enzymes Proteins 0.000 description 2
- 239000003242 anti bacterial agent Substances 0.000 description 2
- 229940088710 antibiotic agent Drugs 0.000 description 2
- 239000003054 catalyst Substances 0.000 description 2
- 239000006194 liquid suspension Substances 0.000 description 2
- 239000000047 product Substances 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 239000007790 solid phase Substances 0.000 description 2
- 229910000906 Bronze Inorganic materials 0.000 description 1
- 239000004743 Polypropylene Substances 0.000 description 1
- 239000010974 bronze Substances 0.000 description 1
- 239000006285 cell suspension Substances 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 238000002386 leaching Methods 0.000 description 1
- 239000012263 liquid product Substances 0.000 description 1
- 230000000813 microbial effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- -1 polypropylene Polymers 0.000 description 1
- 229920001155 polypropylene Polymers 0.000 description 1
- 229910001220 stainless steel Inorganic materials 0.000 description 1
- 239000010935 stainless steel Substances 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000005406 washing Methods 0.000 description 1
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
- B01D29/31—Self-supporting filtering elements
- B01D29/35—Self-supporting filtering elements arranged for outward flow filtration
- B01D29/356—Self-supporting filtering elements arranged for outward 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
- B01D29/88—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
- B01D29/902—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 containing fixed liquid displacement elements or cores
-
- 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
- B01D29/94—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 discharging the filter cake, e.g. chutes
- B01D29/945—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 discharging the filter cake, e.g. chutes for continuously discharging concentrated liquid
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01D—SEPARATION
- B01D2201/00—Details relating to filtering apparatus
- B01D2201/28—Position of the filtering element
- B01D2201/287—Filtering elements with a vertical or inclined rotation or symmetry axis
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Filtration Of Liquid (AREA)
Abstract
Filter housing 1 has a removable cover 2 to enable a tubular filter element 4 to be removed, an inwardly extended inlet tube 7 and an outlet 5 on the upstream side of the element, to produce a fluid flow across said upstream side, and a filtrate outlet 10 or 11 on the downstream side. <IMAGE>
Description
SPECIFICATION
Filtration apparatus
The present invention relates to filtration apparatus.
Filtration techniques are known in which a solid-liquid suspension to be filtered is passed over a filter medium across which a pressure differential is maintained so that filtrate passes through the medium, while solids together with unfiltered liquid exit from the filtration apparatus for collection. Flow conditions are controlled to limit the deposition of solid on the surface of the medium.
Such techniques may be used for separating of liquids from a suspension, or, alternatively, for concentrating a solid-liquid suspension. It will be understood that the solid particles may be of any size and might be so small as not to be visible to the naked eye. It is therefore to be understood that the term "solid" as used herein is intended to refer to any material which it is desired to separate from a liquid, no matter what the size of the material is.
The techniques may be used, for example, for recovery of filtrate containing antibiotics, enzymes etc. or alternatively in the concentration of cell suspensions or in the washing and resuspension of cells.
An example of such a filtration technique is cross-flow filtration, which is also known as tangential flow filtration. Cross-flow filtration apparatus is known in which the filter medium is a porous tube of circular cross-section. The solidliquid suspension is introduced to the interior of the tube at one end thereof, filtrate is collected from outside of the tube, and the concentrated suspension leaves the tube at the opposite end thereof. In an alternative arrangement the suspension flows over the outer surface of the tube from one end thereof to the other, filtrate being collected from the inside of the tube. In each case a pressure difference is maintained across the tube to assist filtration, and flow conditions are designed to be such as to limit deposition of stationary solids on the tube surface.
Whilst such cross-flow filtration apparatus performs the filtration operation effectively, it suffers from the disadvantage that it is difficult to dismantle when it is required to remove the filter medium for cleaning or replacement.
This difficulty is even more severe in a multitubular cross-flow filtration apparatus comprising two end plates and a plurality of elongate tubular filter elements, each extending between the end plates and having its ends located in the respective end plates.
It will be appreciated that it is difficult to remove a single tube from such a construction, since it is necessary to remove at least one of the end plates and possibly one or more of the other filter elements. Additionally, it is necessary, when constructing such multi-tube apparatus, to ensure that the holes in the end plates are accurately aligned with each other since otherwise the filter elements would not locate correctly in position.
It is an object of the invention to provide filtration apparatus in which the above-mentioned
disadvantages are obviated or mitigated.
According to the present invention there is
provided filtration apparatus comprising a housing
incorporating a removable closure member, a filter
element capable of being inserted into and
removed from the housing when the closure
member is removed, means removably securing the filter element in a given location on one part of the housing, a first fluid outlet from the housing
located adjacent to one end of the filter element, a fluid inlet tube extending within the housing from said one end of the filter element and terminating adjacent the other end thereof, the end of the tube and the first fluid outlet lying to the same side of the filter element, and a second fluid outlet from the housing lying to the opposite side of the filter element.
In the apparatus of the invention, it is a simple matter to remove the closure member to gain access to the filter element, and to remove the filter element from the housing. A plurality of filter elements may be arranged in a common housing, all being secured in respective locations within the housing and all accessible when the closure member is opened.
Preferably, the filter element is tubular and preferably the inlet and the first outlet communicates with the interior of the filter element. Suitable sealing arrangements will, of course, be made.
Conveniently, the housing includes a manifold on which the filter element is located, in which the first fluid outlet is formed and from which the fluid inlet tube extends. It is particularly preferred that the securing means for the filter element are connected to the manifold, and that the fluid inlet tube extends through the first fluid outlet into the filter element, the fluid inlet tube, first fluid outlet and filter element all being coaxial.
In use, the apparatus will desirably be oriented with the axis of the tubular element vertical or substantially vertical, although other orientations are possible.
The invention will be further described by way of example only with reference to the accompanying drawing which is a diagrammatic cross-sectional view of one embodiment of filtration apparatus in accordance with the invention.
Referring to the drawing a cross-flow filtration apparatus comprises a housing that includes an annular wall section 1, a cover 2 and a manifold 3.
The wall section 1 and cover 2 may be of integral construction and the whole may thus form a removable closure member that may be releasably secured to the manifold 3 by any suitable means, e.g. clips (not shown). Means will then be provided to ensure that the wall section 2 is sealed against the manifold 3 to prevent egress of liquid during filtration.
Alternatively, the wall section 1 and manifold 3 may be of integral construction, the cover 2 forming a removable closure member releasably secured to, and sealed on, the wall section 1 in any convenient manner. Constructions wherein a removable closure member forms part of the side wall of the housing can also be envisaged. Within the housing is located a tubular filter element 4 which may be of any material appropriate to the suspension to be filtered, for example thick-walled porous plastics tubes or tubes of sintered material, e.g. of stainless steel, phosphor-bronze or polypropylene. The manifold 3 has a central well 3a forming a first liquid outlet from which liquid may be taken by a tube 5. As will be seen from the drawing, the filter element 4 is seated on a gasket 6 around the top of the well 3a.A liquid inlet tube 7 extends coaxially through the well 3a and is part of the manifold 3. Tube 7 extends to a position just short of the top of filter element 4, and is coaxial with the filter element.
A plate 8 is provided as a top closure for the filter element 4, the plate seating on top of the filter element with an interposed gasket 9. Plate 8 is additionally located in position on the inlet tube 7 as shown, and secured thereto by a bolt 9a.
A top filtrate outlet 10 and/or a bottom filtrate outlet 11 are provided in the housing 2, as illustrated.
In use of the apparatus, liquid to be filtered is introduced at high velocity through tube 7 into the top of filter element 4, and then passes along the annular space between the tube 7 and the filter element 4, as indicated by arrows A.
A pressure differential is established by means not shown between the opposite sides of filter element 4 (in any manner customarily used in cross-flow filtration) such that some of the liquid passes through filter element 4 as filtrate (arrows B).
The liquid passing down the annular space between the tube 7 and filter element 4 becomes more and more concentrated in solids until this liquid enters the well 3a and is discharged through outlet tube 5.
It will be seen from the drawing that the liquid moving down the inside of the filter element 4 passes into well 3a (of the same internal diameter as filter element 4) before turning through 90Q and exiting through outlet 5. The provision of well 3a (equal in diameter to filter element 4) ensures reduced restriction to liquid flow out of filter element 4.
Filtrate may be collected, through either of outlets 10 or 1 the use of the latter having the advantage that the housing 2 remains full of filtrate thus preventing the filter element 4 from drying out.
Depending on the desired product, either the filtrate or the more concentrated liquor exiting from outlet 5 is collected. If the latter is collected, it may of course be recycled through the apparatus for further filtration.
The illustrated apparatus may be used, for example, for filtration of liquids containing, as solid particles, precipitated or crystallised products, inert particles in leaching processes, catalyst particles in reactions, or plant, animal or microbial cells. The apparatus could be used, for example, to retain the solid phase within a particular system (e.g. a chemical reactor) from which liquid product must be removed. Thus a suspension of the solid phase (e.g. a catalyst) in the liquid may be passed from the system through the filtration apparatus, the liquid filtrate collected, and the solid suspension returned to the system.
Alternatively, the apparatus may be used for conventional recovery of filtrate containing antibiotics, enzymes etc.
The filtration apparatus of the invention has a number of advantages. In particular, it is easy to gain access to the filter element 4 for replacement thereof simply by removal of the closure member section of the housing 2. Additionally the apparatus may be steam-sterilised, because the ends of the filter tube are not both fixed. There will be no expansion damage during heating, such as would occur in a filtration apparatus in which the filter element was mounted at both its ends in fixed plates. Both of these are considerable advantages over prior art cross-flow filtration apparatus.
It should be appreciated that a number of modifications may be made to the illustrated filtration apparatus. Thus, for example, the filter element 4 may be mounted in a recess in the closure member 3 with the necessary seals being provided by O-rings around the lower peripheral surface of the seal. Alternatively, the end of the filter element may be screw-threaded for engagement within a screw-threaded recess within closure member.
Various different forms of manifold and of mounting filter elements on such manifolds are possible. In some cases it may be desirable for the manifold to form the uppermost part of the housing, with both first outlets formed in the manifold and the fluid inlet tube suitably secured to the manifold to extend downwardly into the filter element, also secured to the manifold.
Filtration apparatus constructed in any of the manners described may be formed with a plurality of filter elements 4 mounted within a single housing. In this case, each element 4 will be associated with a respective inlet tube and first fluid outlet. A common header for the inlet tubes 7 will be provided which feeds said tubes through channels in the manifold. Similarly a common header will be provided for receiving the more concentrated suspension exiting from the interiors of the filter elements, and a common outlet will be provided for receiving the filtrate passing through the elements into the housing. It will be appreciated that any individual filter element may be replaced as required, without having to disturb the mounting of any other element.
In all embodiments of the invention the velocity of the incoming suspension and the manner in which it flows within the filter tube are such as to restrict deposition of stationary solids on the inner surface of the filter tube. As such solids collect on the tube it is recognised that filtering efficiency decreases and accordingly it is desirable to back flush the apparatus from time to time in order to maintain efficiency at an acceptable level. This technique is well known in the art and needs no further description.
Claims (9)
1. Filtration apparatus comprising a housing incorporating a removable closure member, a filter element capable of being inserted into and removed from the housing when the closure member is removed, means removably securing the filter element in a given location on one part of the housing, a first fluid outlet from the housing located adjacent to one end of the filter element, a fluid inlet tube extending within the housing from said one end of the filter element and terminating adjacent the other end thereof, the end of the tube and the first fluid outlet lying to the same side of the filter element, and a second fluid outlet from the housing lying to the opposite side of the filter element.
2. Filtration apparatus according to claim 1 in which the filter element is tubular.
3. Filtration apparatus according to claim 1 or claim 2 in which the first fluid outlet and the fluid inlet tube communicate with the interior of the filter element.
4. Filtration apparatus according to any one of the preceding claims in which the housing includes a manifold on which the filter element is located, in which the first fluid outlet is formed and from which the fluid inlet tube extends.
5. Filtration apparatus according to claim 4 in which the securing means for the filter element are connected to the manifold.
6. Filtration apparatus according to claim 5 in which the securing means for the filter element are connected to the tube at the end of the tube remote from the manifold.
7. Filtration apparatus according to claim 5 or claim 6 and including sealing means between the filter element and the manifold.
8. Filtration apparatus according to claim 4 in which the fluid inlet tube extends through the first fluid outlet into the filter element, the fluid inlet tube, first fluid outlet and filter element all being coaxial.
9. Filtration apparatus substantially as herein described with reference to Figure 1 or Figure 2 of the accompanying drawings.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB08330562A GB2130111A (en) | 1982-11-17 | 1983-11-16 | Filtration apparatus |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8232843 | 1982-11-17 | ||
| GB08330562A GB2130111A (en) | 1982-11-17 | 1983-11-16 | Filtration apparatus |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB8330562D0 GB8330562D0 (en) | 1983-12-21 |
| GB2130111A true GB2130111A (en) | 1984-05-31 |
Family
ID=26284430
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB08330562A Withdrawn GB2130111A (en) | 1982-11-17 | 1983-11-16 | Filtration apparatus |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2130111A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0399309A2 (en) * | 1989-05-23 | 1990-11-28 | Sartorius Ag | Tubular filter element |
| EP0484504A1 (en) * | 1990-05-24 | 1992-05-13 | Miller Leaman, Inc. | Self-cleaning filter for fluid distribution systems |
| GB2383001A (en) * | 2001-12-12 | 2003-06-18 | Shih-Chang Chang | Filter with means for retarding cake formation |
| FR2877950A1 (en) * | 2004-11-17 | 2006-05-19 | Inst Francais Du Petrole | DEVICE FOR PRODUCING LIQUID HYDROCARBONS BY FISCHER-TROPSCH SYNTHESIS IN A THREE-PHASE BED REACTOR |
| EP2108426A1 (en) * | 2008-03-31 | 2009-10-14 | Perkins Engines Company Limited | Fluid filtration device with self cleaning properties |
| CN103949102A (en) * | 2014-05-22 | 2014-07-30 | 李广连 | Filter for machining cooling liquid |
| WO2018175706A1 (en) * | 2017-03-24 | 2018-09-27 | Fmc Technologies, Inc. | Modular flowback filter system |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB959757A (en) * | 1963-01-14 | 1964-06-03 | Davco Proprietary Ltd | Diatomaceous earth or like filter |
| EP0057034A2 (en) * | 1981-01-22 | 1982-08-04 | AB Metall- & Bergprodukter | A device for the filtration of fluids |
-
1983
- 1983-11-16 GB GB08330562A patent/GB2130111A/en not_active Withdrawn
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB959757A (en) * | 1963-01-14 | 1964-06-03 | Davco Proprietary Ltd | Diatomaceous earth or like filter |
| EP0057034A2 (en) * | 1981-01-22 | 1982-08-04 | AB Metall- & Bergprodukter | A device for the filtration of fluids |
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0399309A2 (en) * | 1989-05-23 | 1990-11-28 | Sartorius Ag | Tubular filter element |
| FR2647362A1 (en) * | 1989-05-23 | 1990-11-30 | Sartorius Gmbh | TUBULAR FILTER ELEMENT FOR OVERFLOW FILTRATION |
| DE3916744A1 (en) * | 1989-05-23 | 1990-12-13 | Sartorius Gmbh | TUBULAR FILTER ELEMENT |
| EP0399309A3 (en) * | 1989-05-23 | 1990-12-19 | Sartorius Ag | Tubular filter element |
| EP0484504A1 (en) * | 1990-05-24 | 1992-05-13 | Miller Leaman, Inc. | Self-cleaning filter for fluid distribution systems |
| EP0484504A4 (en) * | 1990-05-24 | 1992-11-19 | James E. Thompson | Self-cleaning filter for fluid distribution systems |
| GB2383001A (en) * | 2001-12-12 | 2003-06-18 | Shih-Chang Chang | Filter with means for retarding cake formation |
| GB2383001B (en) * | 2001-12-12 | 2004-01-28 | Shih-Chang Chang | A filtration device with cross-flow function and a filtration method |
| FR2877950A1 (en) * | 2004-11-17 | 2006-05-19 | Inst Francais Du Petrole | DEVICE FOR PRODUCING LIQUID HYDROCARBONS BY FISCHER-TROPSCH SYNTHESIS IN A THREE-PHASE BED REACTOR |
| WO2006053982A1 (en) * | 2004-11-17 | 2006-05-26 | Institut Francais Du Petrole | Device for producing liquid hydrocarbons by fischer-tropsch synthesis in a three-phase bed reactor |
| US7935313B2 (en) | 2004-11-17 | 2011-05-03 | IFP Energies Nouvelles | Device for producing liquid hydrocarbons by Fischer-Tropsch synthesis in a three-phase bed reactor |
| EP2108426A1 (en) * | 2008-03-31 | 2009-10-14 | Perkins Engines Company Limited | Fluid filtration device with self cleaning properties |
| CN103949102A (en) * | 2014-05-22 | 2014-07-30 | 李广连 | Filter for machining cooling liquid |
| WO2018175706A1 (en) * | 2017-03-24 | 2018-09-27 | Fmc Technologies, Inc. | Modular flowback filter system |
Also Published As
| Publication number | Publication date |
|---|---|
| GB8330562D0 (en) | 1983-12-21 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |