WO1997019299A1 - Filter assembly - Google Patents

Filter assembly Download PDF

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Publication number
WO1997019299A1
WO1997019299A1 PCT/GB1996/002894 GB9602894W WO9719299A1 WO 1997019299 A1 WO1997019299 A1 WO 1997019299A1 GB 9602894 W GB9602894 W GB 9602894W WO 9719299 A1 WO9719299 A1 WO 9719299A1
Authority
WO
WIPO (PCT)
Prior art keywords
filter
assembly
filter assembly
biocide
glass fibre
Prior art date
Application number
PCT/GB1996/002894
Other languages
French (fr)
Inventor
Fredrick Ian Wood
Original Assignee
Nationwide Filter Company 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 Nationwide Filter Company Limited filed Critical Nationwide Filter Company Limited
Publication of WO1997019299A1 publication Critical patent/WO1997019299A1/en

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D39/00—Filtering material for liquid or gaseous fluids
    • B01D39/08—Filter cloth, i.e. woven, knitted or interlaced material
    • B01D39/086—Filter cloth, i.e. woven, knitted or interlaced material of inorganic material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D39/00—Filtering material for liquid or gaseous fluids
    • B01D39/14—Other self-supporting filtering material ; Other filtering material
    • B01D39/20—Other self-supporting filtering material ; Other filtering material of inorganic material, e.g. asbestos paper, metallic filtering material of non-woven wires
    • B01D39/2003—Glass or glassy material
    • B01D39/2017—Glass or glassy material the material being filamentary or fibrous
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D39/00—Filtering material for liquid or gaseous fluids
    • B01D39/14—Other self-supporting filtering material ; Other filtering material
    • B01D39/20—Other self-supporting filtering material ; Other filtering material of inorganic material, e.g. asbestos paper, metallic filtering material of non-woven wires
    • B01D39/2055—Carbonaceous material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B01D53/84—Biological processes
    • B01D53/85—Biological processes with gas-solid contact
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/04—Additives and treatments of the filtering material
    • B01D2239/0407—Additives and treatments of the filtering material comprising particulate additives, e.g. adsorbents
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/04—Additives and treatments of the filtering material
    • B01D2239/0442—Antimicrobial, antibacterial, antifungal additives
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/04—Additives and treatments of the filtering material
    • B01D2239/0464—Impregnants
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/04—Additives and treatments of the filtering material
    • B01D2239/0471—Surface coating material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/06—Filter cloth, e.g. knitted, woven non-woven; self-supported material
    • B01D2239/0604—Arrangement of the fibres in the filtering material
    • B01D2239/0618—Non-woven
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/06—Filter cloth, e.g. knitted, woven non-woven; self-supported material
    • B01D2239/065—More than one layer present in the filtering material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/06—Filter cloth, e.g. knitted, woven non-woven; self-supported material
    • B01D2239/065—More than one layer present in the filtering material
    • B01D2239/0668—The layers being joined by heat or melt-bonding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/06—Filter cloth, e.g. knitted, woven non-woven; self-supported material
    • B01D2239/065—More than one layer present in the filtering material
    • B01D2239/0681—The layers being joined by gluing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2239/00—Aspects relating to filtering material for liquid or gaseous fluids
    • B01D2239/12—Special parameters characterising the filtering material
    • B01D2239/1291—Other parameters
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02A—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE
    • Y02A50/00—TECHNOLOGIES FOR ADAPTATION TO CLIMATE CHANGE in human health protection, e.g. against extreme weather
    • Y02A50/20—Air quality improvement or preservation, e.g. vehicle emission control or emission reduction by using catalytic converters

Definitions

  • the present invention relates lo a filter intended particularly but not exclusively for use in an air-conditioning system of a building.
  • Filters for use in building air conditioning are typically made from filtering media comprised of glass fibre matt, synthetic fibre matt or glass fibre paper. Filters of glass fibre matt or synthetic fibre matt are generally configured as either flat pads, as bag or pocket filters, or pleated. Glass fibre paper is generally always pleated to give a high surface area.
  • the air conditioning filter will become biologically contaminated in use. The contamination usually takes the form of mould, fungus and bacterial growth and is particularly evident on the influent (“dirty 1" ) side of the filter. Depending on the efficiency of the filter this biological contamination can be distributed throughout the building and recent investigations have suggested that this may be a contributory factor in "sick building syndrome".
  • a biocide In order to prevent biological contamination of the filter media, a biocide can be used to treat the surface. However, in practice this often results in an increase in air resistance, either immediately on application of the biocide or during use.
  • a filter assembly comprising a primary filter and a secondary filter of lower filtering efficiency than the primary filter wherein the secondary filter is treated with a biocide.
  • the filter assembly is particularly useful for use in air conditioning systems.
  • the secondary filter will be located on the influent side of the primary filter.
  • the secondary filter serves to provide a biocidal treatment to the air being filtered before it reaches the primary filter (which provides the significant part of the filtering capacity of the assembly). Therefore mould, fungal and bacterial growth on the influent side (and consequential blockage) of the primary filter is avoided.
  • the secondary filter also provides additional filtering capacity for the assembly (as compared to that provided by the primary filter alone).
  • the primary filter is preferably a pleated filter.
  • the pleats o the primary filter are preferably set apart to allow air to flow across all the filtering media
  • the spacing can be achieved using separate corrugated spaces, e.g. card or aluminium or by use of ribs of hot melt adhesive. It is however preferred that the spacer on one side (the influent side) is provided by the secondary filter.
  • the primary filter is preferably glass fibre paper but could alternatively be a glass fibre matt or synthetic fibre matt.
  • the secondary filter may be a non-woven material. most preferably of polyester.
  • the secondary filter preferably has a thickness of 1 to 6mm. more preferably 1 to 3mm.
  • the filter assembly may incorporate a carbon containing substrate, e.g. charcoal cloth, charcoal paper, charcoal impregnated form or any other media which absorbs gases and vapours.
  • a carbon containing substrate e.g. charcoal cloth, charcoal paper, charcoal impregnated form or any other media which absorbs gases and vapours.
  • the carbon containing substrate is for preference provided on the side of the primary filter remote from the secondary filter.
  • a preferred filter assembly in accordance with the invention comprises a copleated assembly of a glass fibre paper and a non-woven polyester matt treated with a biocide.
  • Such an assembly is preferably produced by bonding the polyester matt to the glass fibre paper by means of a suitable adhesive, e.g. a hot melt glue, water based PVA or latex.
  • a suitable adhesive e.g. a hot melt glue, water based PVA or latex.
  • This composite media is then treated so as lo impregnate the polyester matt with a biocide.
  • the biocide composite media may then be pleated, lf desired the copleated assembly may incorporate a carbon containing substrate for adsorption o gases and vapours.
  • biocide treated polyester matt may be incorporated in the filter assembly, ln this case, the layers of biocide treated polyester matt may be on the same side as, or on either side of, the primary filter.
  • the biocide for use in filter assemblies in accordance with the criteria may for example be Bacterigard FS as supplied by Liquid Technology Ltd.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Biomedical Technology (AREA)
  • Health & Medical Sciences (AREA)
  • Geology (AREA)
  • Environmental & Geological Engineering (AREA)
  • Molecular Biology (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Inorganic Chemistry (AREA)
  • Textile Engineering (AREA)
  • Filtering Materials (AREA)

Abstract

A filter assembly comprises a primary filter and a secondary filter of lower filtering efficiency than the primary filter. The secondary filter is treated with a biocide which serves to prevent or reduce biological contamination of the filter assembly. A preferred embodiment of the filter assembly comprises a copleated assembly of a glass fibre paper (primary filter) and a non-woven polyester matt (secondary filter) treated with a biocide. The filter assembly is particularly useful for use in air conditioning systems.

Description

FILTER ASSEMBLY
The present invention relates lo a filter intended particularly but not exclusively for use in an air-conditioning system of a building.
Filters for use in building air conditioning are typically made from filtering media comprised of glass fibre matt, synthetic fibre matt or glass fibre paper. Filters of glass fibre matt or synthetic fibre matt are generally configured as either flat pads, as bag or pocket filters, or pleated. Glass fibre paper is generally always pleated to give a high surface area. In all cases the air conditioning filter will become biologically contaminated in use. The contamination usually takes the form of mould, fungus and bacterial growth and is particularly evident on the influent ("dirty1") side of the filter. Depending on the efficiency of the filter this biological contamination can be distributed throughout the building and recent investigations have suggested that this may be a contributory factor in "sick building syndrome".
The use of higher efficiency glass fibre paper filters reduces the transmission of biological contamination but does not remove it completely.
In order to prevent biological contamination of the filter media, a biocide can be used to treat the surface. However, in practice this often results in an increase in air resistance, either immediately on application of the biocide or during use.
It is therefore an object of the invention to obviate or mitigate the above- mentioned disadvantage.
According to the present invention there is provided a filter assembly comprising a primary filter and a secondary filter of lower filtering efficiency than the primary filter wherein the secondary filter is treated with a biocide.
The filter assembly is particularly useful for use in air conditioning systems. In use the secondary filter will be located on the influent side of the primary filter.
The secondary filter serves to provide a biocidal treatment to the air being filtered before it reaches the primary filter (which provides the significant part of the filtering capacity of the assembly). Therefore mould, fungal and bacterial growth on the influent side (and consequential blockage) of the primary filter is avoided. The secondary filter also provides additional filtering capacity for the assembly (as compared to that provided by the primary filter alone).
The primary filter is preferably a pleated filter. The pleats o the primary filter are preferably set apart to allow air to flow across all the filtering media
The spacing can be achieved using separate corrugated spaces, e.g. card or aluminium or by use of ribs of hot melt adhesive. It is however preferred that the spacer on one side (the influent side) is provided by the secondary filter.
The primary filter is preferably glass fibre paper but could alternatively be a glass fibre matt or synthetic fibre matt.
The secondary filter may be a non-woven material. most preferably of polyester. The secondary filter preferably has a thickness of 1 to 6mm. more preferably 1 to 3mm.
If the filter assembly is to be used where the removal of noxious gases and vapours at low concentration is required, the assembly may incorporate a carbon containing substrate, e.g. charcoal cloth, charcoal paper, charcoal impregnated form or any other media which absorbs gases and vapours. The carbon containing substrate is for preference provided on the side of the primary filter remote from the secondary filter.
A preferred filter assembly in accordance with the invention comprises a copleated assembly of a glass fibre paper and a non-woven polyester matt treated with a biocide. Such an assembly is preferably produced by bonding the polyester matt to the glass fibre paper by means of a suitable adhesive, e.g. a hot melt glue, water based PVA or latex. This composite media is then treated so as lo impregnate the polyester matt with a biocide. The biocide composite media may then be pleated, lf desired the copleated assembly may incorporate a carbon containing substrate for adsorption o gases and vapours. Alternatively or additionally two or more layers of biocide treated polyester matt may be incorporated in the filter assembly, ln this case, the layers of biocide treated polyester matt may be on the same side as, or on either side of, the primary filter. The biocide for use in filter assemblies in accordance with the criteria may for example be Bacterigard FS as supplied by Liquid Technology Ltd.

Claims

1 . A filter assembly comprising a primary filter and a secondary filter of lower filtering efficiency than the primary filter wherein the secondary filter is treated with a biocide.
2. A filter assembly as claimed in claim 1 wherein the primary filter is glass fibre paper.
3. A filter assembly as claimed in claim 2 wherein the glass fibre paper is copleated with the secondary filter.
4. A filter assembly as claimed in any one of claims 1 to 3 wherein the secondary filter is a non- woven material.
5. A filter assembly as claimed in claim 4 wherein the secondary filter is of polyester.
6. A filter assembly as claimed in any one of claims 1 to 5 wherein the secondary filter has a thickness of 1 to 6mm.
7. A filter assembly as claimed in claim 6 wherein the secondary filter has a thickness of 1 to 3mm.
8. A filter assembly as claimed in any one of claims 1 to 7 further comprising a carbon containing substrate.
9. A filter containing assembly as claimed in claim 8 wherein the carbon containing substrate is provided on the side of the primary filter remote from the secondary filter.
10. A filter assembly comprising a glass fibre paper copleated with a polyester matt treated with a biocide. the polyester matt being of lower filtering efficiency than the glass fibre paper.
1 1. A method of producing a filter assembly as claimed in claim 10 comprising the bonding of the polyester matt to the glass fibre paper to produce a composite media, treating the composite media so as to impregnate the polyester matt with a biocide, and then pleating the biocide treated composite media.
PCT/GB1996/002894 1995-11-23 1996-11-25 Filter assembly WO1997019299A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB9523919.0 1995-11-23
GB9523919A GB2307425A (en) 1995-11-23 1995-11-23 Filter assembly with biocide

Publications (1)

Publication Number Publication Date
WO1997019299A1 true WO1997019299A1 (en) 1997-05-29

Family

ID=10784302

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/GB1996/002894 WO1997019299A1 (en) 1995-11-23 1996-11-25 Filter assembly

Country Status (2)

Country Link
GB (1) GB2307425A (en)
WO (1) WO1997019299A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2325181B (en) * 1997-05-16 2001-07-18 Upf Corp Self-supporting pleated filter composite and methods of making it

Families Citing this family (13)

* Cited by examiner, † Cited by third party
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US5868933A (en) * 1995-12-15 1999-02-09 Patrick; Gilbert Antimicrobial filter cartridge
KR100853920B1 (en) 2000-03-14 2008-08-25 제임스 하디 인터내셔널 파이낸스 비.브이. Fiber cement building materials with low density additives
AU2001242108B9 (en) * 2000-03-29 2005-04-14 Novapharm Research (Australia) Pty Ltd Biostatic filter
CN1246246C (en) 2000-10-04 2006-03-22 詹姆斯哈迪国际财金公司 Fiber cement composition materials using cellulose fibers loaded with inorganic and/or organic substances
JP5226925B2 (en) 2000-10-17 2013-07-03 ジェイムズ ハーディー テクノロジー リミテッド Fiber cement composite using durable cellulose fibers treated with biocides
AU2001296904B2 (en) 2000-10-17 2007-08-30 James Hardie Technology Limited Method and apparatus for reducing impurities in cellulose fibers for manufacture of fiber reinforced cement composite materials
CZ20032693A3 (en) 2001-03-09 2004-07-14 James Hardie Research Pty. Limited Fiber reinforced cement composite materials employing chemically treated fibers exhibiting enhanced dispersing property
MXPA05003691A (en) 2002-10-07 2005-11-17 James Hardie Int Finance Bv Durable medium-density fibre cement composite.
NZ541250A (en) 2003-01-09 2008-09-26 James Hardie Int Finance Bv Fibre cement composite materials using bleached cellulose fibres
US7998571B2 (en) 2004-07-09 2011-08-16 James Hardie Technology Limited Composite cement article incorporating a powder coating and methods of making same
CA2648966C (en) 2006-04-12 2015-01-06 James Hardie International Finance B.V. A surface sealed reinforced building element
US8209927B2 (en) 2007-12-20 2012-07-03 James Hardie Technology Limited Structural fiber cement building materials
DE102011104628A1 (en) 2011-06-06 2012-12-06 Mann + Hummel Gmbh Antimicrobial filter medium and filter module

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Publication number Priority date Publication date Assignee Title
US4177143A (en) * 1978-10-25 1979-12-04 Nalco Chemical Company Elimination of strainer fouling in recirculating cooling water systems
JPS58101717A (en) * 1981-12-11 1983-06-17 Hitachi Ltd Filter for air-conditioner
JPS61268327A (en) * 1985-05-23 1986-11-27 Toray Ind Inc Filter material for organic polymer solution
JPS63315119A (en) * 1987-06-16 1988-12-22 Matsushita Electric Ind Co Ltd Air cleaner filter
JPS647921A (en) * 1987-06-29 1989-01-11 Matsushita Electric Ind Co Ltd Filter
GB2221844A (en) * 1988-07-19 1990-02-21 Protector Safety Ltd Respirator filter
JPH02198631A (en) * 1989-01-28 1990-08-07 Osaka Gas Co Ltd Laminated adsorbent and its production
US5006267A (en) * 1989-11-08 1991-04-09 The Dow Chemical Company Biocidal fluid filters

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JPH08238307A (en) * 1995-03-06 1996-09-17 Suntory Ltd Disinfecting filter and sterilization maintaining device for sterile room

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Publication number Priority date Publication date Assignee Title
US4177143A (en) * 1978-10-25 1979-12-04 Nalco Chemical Company Elimination of strainer fouling in recirculating cooling water systems
JPS58101717A (en) * 1981-12-11 1983-06-17 Hitachi Ltd Filter for air-conditioner
JPS61268327A (en) * 1985-05-23 1986-11-27 Toray Ind Inc Filter material for organic polymer solution
JPS63315119A (en) * 1987-06-16 1988-12-22 Matsushita Electric Ind Co Ltd Air cleaner filter
JPS647921A (en) * 1987-06-29 1989-01-11 Matsushita Electric Ind Co Ltd Filter
GB2221844A (en) * 1988-07-19 1990-02-21 Protector Safety Ltd Respirator filter
JPH02198631A (en) * 1989-01-28 1990-08-07 Osaka Gas Co Ltd Laminated adsorbent and its production
US5006267A (en) * 1989-11-08 1991-04-09 The Dow Chemical Company Biocidal fluid filters

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DATABASE WPI Section Ch Week 8908, Derwent World Patents Index; Class A88, AN 89-056808, XP002027330 *
DATABASE WPI Section Ch Week 9037, Derwent World Patents Index; Class A88, AN 90-280144, XP002027329 *
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2325181B (en) * 1997-05-16 2001-07-18 Upf Corp Self-supporting pleated filter composite and methods of making it

Also Published As

Publication number Publication date
GB2307425A (en) 1997-05-28
GB9523919D0 (en) 1996-01-24

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