CH661668A5 - POROUS SUPPORT LAYER FOR A KIESELGUR FILTER CAKE formed by precoat and METHOD FOR THE PRODUCTION THEREOF. - Google Patents
POROUS SUPPORT LAYER FOR A KIESELGUR FILTER CAKE formed by precoat and METHOD FOR THE PRODUCTION THEREOF. Download PDFInfo
- Publication number
- CH661668A5 CH661668A5 CH619/83A CH61983A CH661668A5 CH 661668 A5 CH661668 A5 CH 661668A5 CH 619/83 A CH619/83 A CH 619/83A CH 61983 A CH61983 A CH 61983A CH 661668 A5 CH661668 A5 CH 661668A5
- Authority
- CH
- Switzerland
- Prior art keywords
- fibers
- support layer
- polyolefin fibers
- drying
- native
- Prior art date
Links
- 239000005909 Kieselgur Substances 0.000 title claims description 8
- 238000004519 manufacturing process Methods 0.000 title claims description 8
- 238000000034 method Methods 0.000 title claims description 7
- 239000012065 filter cake Substances 0.000 title claims 2
- 239000000835 fiber Substances 0.000 claims description 44
- 229920000098 polyolefin Polymers 0.000 claims description 13
- -1 polyethylene Polymers 0.000 claims description 10
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 9
- 238000001035 drying Methods 0.000 claims description 6
- 239000004698 Polyethylene Substances 0.000 claims description 5
- 239000004743 Polypropylene Substances 0.000 claims description 5
- 229920000573 polyethylene Polymers 0.000 claims description 5
- 229920001155 polypropylene Polymers 0.000 claims description 5
- 238000005245 sintering Methods 0.000 claims description 3
- 230000000877 morphologic effect Effects 0.000 claims description 2
- 238000005728 strengthening Methods 0.000 claims description 2
- 239000007900 aqueous suspension Substances 0.000 claims 2
- 239000003795 chemical substances by application Substances 0.000 claims 2
- 239000011230 binding agent Substances 0.000 description 6
- 230000008961 swelling Effects 0.000 description 6
- 238000001914 filtration Methods 0.000 description 5
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 239000000725 suspension Substances 0.000 description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 3
- 229920000742 Cotton Polymers 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 239000012209 synthetic fiber Substances 0.000 description 2
- 229920002994 synthetic fiber Polymers 0.000 description 2
- 229920003043 Cellulose fiber Polymers 0.000 description 1
- 239000000853 adhesive Substances 0.000 description 1
- 230000001070 adhesive effect Effects 0.000 description 1
- 206010061592 cardiac fibrillation Diseases 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 230000001427 coherent effect Effects 0.000 description 1
- 238000007596 consolidation process Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000018109 developmental process Effects 0.000 description 1
- 208000037265 diseases, disorders, signs and symptoms Diseases 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 230000002600 fibrillogenic effect Effects 0.000 description 1
- 239000012784 inorganic fiber Substances 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000002844 melting Methods 0.000 description 1
- 230000008018 melting Effects 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 230000001954 sterilising effect Effects 0.000 description 1
- 238000004659 sterilization and disinfection Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
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
- B01D39/14—Other self-supporting filtering material ; Other filtering material
- B01D39/16—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres
- B01D39/1607—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres the material being fibrous
- B01D39/1615—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres the material being fibrous of natural origin
-
- 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
- B01D39/16—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres
- B01D39/1607—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres the material being fibrous
- B01D39/1623—Other self-supporting filtering material ; Other filtering material of organic material, e.g. synthetic fibres the material being fibrous of synthetic origin
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H13/00—Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material
- D21H13/10—Organic non-cellulose fibres
- D21H13/12—Organic non-cellulose fibres from macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
- D21H13/14—Polyalkenes, e.g. polystyrene polyethylene
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H5/00—Special paper or cardboard not otherwise provided for
- D21H5/12—Special paper or cardboard not otherwise provided for characterised by the use of special fibrous materials
- D21H5/20—Special paper or cardboard not otherwise provided for characterised by the use of special fibrous materials of organic non-cellulosic fibres too short for spinning, with or without cellulose fibres
- D21H5/202—Special paper or cardboard not otherwise provided for characterised by the use of special fibrous materials of organic non-cellulosic fibres too short for spinning, with or without cellulose fibres polyolefins
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Filtering Materials (AREA)
- Nonwoven Fabrics (AREA)
Description
Die Erfindung bezieht sich auf eine poröse Stützschicht gemäss dem Oberbegriff des Patentanspruchs 1 sowie auf ein Verfahren zu deren Herstellung nach dem Oberbegriff des Patentanspruchs 4. The invention relates to a porous support layer according to the preamble of patent claim 1 and to a method for its production according to the preamble of patent claim 4.
Stützschichten dienen bei der Kieselgur-Anschwemmfil-tration in entsprechenden Filterpressen als poröse, wasserdurchlässige Schichten, auf welche das Filtermittel — die Kieselgur — aufgeschwemmt wird und sich dadurch der filtrierende Kieselgurkuchen bildet. Nach Beendigung eines Filtrations-Zyklus wird die Filterpresse geöffnet, der Kieselgurkuchen von den Stützschichten abgeschabt und abgespritzt. Anschliessend wird die Filterpresse wieder zugefahren und ein weiterer Filtrations-Zyklus kann beginnen. In the case of diatomaceous earth precoat filtration, support layers serve as porous, water-permeable layers in appropriate filter presses, onto which the filter medium - the diatomaceous earth - is suspended and the filtering diatomaceous earth cake forms. At the end of a filtration cycle, the filter press is opened, the kieselguhr cake scraped off the supporting layers and sprayed off. The filter press is then closed again and another filtration cycle can begin.
Durch die DE-PS 933 447 sind grobporige Stützschichten aus organischen oder anorganischen Fasern oder Gemischen dieser Fasern bekannt, die als Unterlage für eine daraufliegende feinporige Filterschicht dienen. Sie sind nach Art papiermässiger Verarbeitung hergestellt und zur Vermeidung von Abfaserungen mit Bindemitteln zur Verfestigung • der Fasern behandelt. Als Bindemittel dienen gegenüber der zu filtrierenden Flüssigkeit unlösliche Klebstoffe, Harze od.dgl., die über die Faserverfestigung hinaus die Widerstandsfähigkeit der Stützschicht gegen mechanische Beanspruchungen erhöhen sowie ihre Nassfesteigenschaften zur Vermeidung von Quelldehnungen im nassen Zustand verbessern sollen. Es hat sich jedoch gezeigt, dass die mit den angegebenen Bindemitteln behandelten bekannten Stützschichten bezüglich ihrer Nassfesteigenschaften den Anforderungen der Praxis nicht oder nur unvollkommen genügen. Mit der Dauer des Einsatzes der bekannten Stützschichten, insbesondere bei mehrfachem Sterilisieren mit Dampf oder Heiss-wasser, verringert sich der Nassfesteffekt, so dass Beschädigungen auftreten, die den Einsatz neuer Stützschichten erfordern. Mit geringem Nassfesteffekt verbunden ist auch der Anstieg der Quelldehnungen, was zu einer umständlichen Arbeitsweise mit den Stützschichten führt, indem sie vor dem Gebrauch mittels Durchfeuchten auf das Endmass vorzuquellen sind. Bei den für die bekannten Stützschichten vorgesehenen Bindemitteln ist ausserdem darauf zu achten, dass diese für den Einsatz zur Nassfestausrüstung der Stützschichten nach geltendem Lebensmittelrecht unbedenklich sind und Harze, die Formaldehyde abspalten, als Bindemittel von vornherein ausscheiden. From DE-PS 933 447 coarse-pore support layers made of organic or inorganic fibers or mixtures of these fibers are known, which serve as a base for a fine-pore filter layer lying thereon. They are manufactured in the manner of paper-like processing and treated with binders to strengthen the fibers in order to avoid fibrillation. As a binder, insoluble adhesives, resins or the like are used with respect to the liquid to be filtered, which, in addition to fiber consolidation, are intended to increase the resistance of the support layer to mechanical stresses and to improve its wet strength properties to avoid swelling expansions when wet. However, it has been shown that the known support layers treated with the specified binders do not or only incompletely meet the requirements of practice with regard to their wet strength properties. With the duration of use of the known support layers, in particular in the case of multiple sterilization with steam or hot water, the wet strength effect is reduced, so that damage occurs which requires the use of new support layers. The increase in swelling elongation is also associated with a low wet strength effect, which leads to a cumbersome way of working with the support layers, in that they have to be pre-swollen to the final size by means of dampening before use. In the case of the binders provided for the known support layers, care must also be taken to ensure that they are safe for use in the wet-strengthening of the support layers in accordance with current food law and that resins which release formaldehyde are eliminated as binders from the outset.
Aufgabe der Erfindung ist es daher, eine Stützschicht und ein Verfahren zu deren Herstellung anzugeben, die unter Vermeidung von nach geltendem Lebensmittelrecht unzulässigen Bindemitteln sowohl hervorragende Nassfesteigenschaften aufweist als auch praktisch frei ist von Quelldehnungen, die das umständliche Vorquellen bisheriger Stützschichten auf das Endmass erübrigen. It is therefore an object of the invention to provide a support layer and a method for its production which, while avoiding binders which are not permitted under current food law, both have excellent wet strength properties and are practically free of swelling strains which make the cumbersome pre-swelling of previous support layers unnecessary.
Diese Aufgabe wird für die Stützschicht mit den kennzeichnenden Merkmalen des Patentanspruchs 1 und für das Verfahren zu deren Herstellung mit den kennzeichnenden Merkmalen des Patentanspruchs 4 gelöst. Hierbei können gemäss besonderen Ausbildungen der Erfindung die Polyolefinfasern aus reinem Polyethylen oder aus reinem Polypropylen bestehen. This object is achieved for the support layer with the characterizing features of patent claim 1 and for the method for its production with the characterizing features of patent claim 4. According to special embodiments of the invention, the polyolefin fibers can consist of pure polyethylene or of pure polypropylene.
Weiterbildungen der von der Erfindung angegebenen Verfahrensweise zur Herstellung der Stützschicht werden in den Patentansprüchen 5 und 6 beschrieben. Further developments of the procedure for producing the support layer specified by the invention are described in patent claims 5 and 6.
Durch eine genaue Temperaturführung bei der Trocknung sintern die Polyolefinfasern an den Kreuzungs- oder Berührungsstellen mit den nativen Fasern und auch untereinander, so dass die Stützschicht nach dem Erkalten ein weitgehend zusammenhängendes Fasergefüge aufweist. Eine derartige Stützschicht ist praktisch abfaserungsfrei. Durch die Reduktion der Quelldehnung ist sie ausserdem von bester Nassfesteigenschaft und überdies lebensmittelrechtlich unbedenklich. Auch ist ihre Gebrauchsdauer für den Filtrationseinsatz erheblich länger. Due to precise temperature control during drying, the polyolefin fibers sinter at the intersections or points of contact with the native fibers and also with one another, so that the support layer has a largely coherent fiber structure after cooling. Such a support layer is practically free of fibers. By reducing the swelling expansion, it is also of the best wet-strength properties and is also harmless under food law. Their service life for filtration is also significantly longer.
Die Herstellung der erfindungsgemässen Kieselgurstützschichten erfolgt in der Weise, dass ein Faserstoffbrei aus Zellstoff oder anderen nativen Fasern, z.B. aus Baumwoll-Linters, besteht — üblicherweise verwendet man Mischungen aus Zellstoff-Fasern und Baumwoll-Linters — dem, bezogen auf die Gesamtfasermasse der Kieselgurstützschicht (trockengedacht), 20—50 Gewichts-% Polyolefinfasern als reine Polyethylenfasern oder reine Polypropylenfasern mit jeweiliger Faserlänge von 0,8—1,2 mm zugemischt werden. Es handelt sich immer um wässrige Fasersuspensionen. Dieses Stoffgemisch mit Wasser als Suspensionsträger der nativen wie der synthetischen Fasern wird vor der Schichtenherstellung auf eine Stoffdichte von 0,5—1 % verdünnt und auf ein umlaufendes, endloses Siebband einer Herstellungsmaschine, ähnlich der bekannten Papiermaschinen, aufgebracht und mittels Falldruck, anschliessend mittels Saugern durch Vakuum der Suspension durch das Siebband hindurch das Wasser entzogen. Dadurch bildet sich auf dem Siebgewebe aus den nativen und synthetischen Fasern eine Schicht, in welcher die Fasern in einer sinnvollen Unordnung, recht gleichmässig in X-, Y- und Z-Achse verteilt sind. Die Siebbandgeschwindigkeit der Herstellungsmaschine wird je nach herzustellendem Flächengewicht der Schicht mit 5—25 m/ min. eingestellt. The diatomaceous earth support layers according to the invention are produced in such a way that a pulp of cellulose or other native fibers, e.g. consists of cotton linters - usually one uses mixtures of cellulose fibers and cotton linters - which, based on the total fiber mass of the kieselguhr support layer (dry), contains 20-50% by weight polyolefin fibers as pure polyethylene fibers or pure polypropylene fibers with a respective fiber length of 0 , 8-1.2 mm can be added. It is always about aqueous fiber suspensions. This mixture of substances with water as a suspension carrier of the native and synthetic fibers is diluted to a consistency of 0.5-1% before layer production and applied to a continuous, continuous screen belt of a manufacturing machine, similar to the known paper machines, and by means of drop pressure, then by means of suction cups the water is removed by vacuuming the suspension through the sieve belt. As a result, a layer is formed on the screen fabric from the native and synthetic fibers, in which the fibers are distributed in a reasonable disorder, quite evenly in the X, Y and Z axes. The belt speed of the production machine is 5 - 25 m / min depending on the basis weight of the layer to be produced. set.
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Die Schicht läuft anschliessend auf einem Flachdraht-Siebband liegend durch einen Trockner, in welchem die Schicht mittels Heissluft getrocknet und die Polyolefinfasern durch genaue Temperaturführung — für Polyethylenfasern > 125 °C < 140 °C, für Polypropylenfasern > 150 °C < 170 °C — sowohl miteinander, wie auch mit den nativen Fasern gesintert werden. Dieses Sintern der Fasern mitein- The layer then runs on a flat wire sieve belt through a dryer, in which the layer is dried using hot air and the polyolefin fibers by precise temperature control - for polyethylene fibers> 125 ° C <140 ° C, for polypropylene fibers> 150 ° C <170 ° C - are sintered with each other as well as with the native fibers. This sintering of the fibers
661 668 661 668
ander ergibt die gewünschte hohe Nassfestigkeit der Schicht und gleichfalls die erwünschte stark reduzierte Quellung der Schicht bei der Durchfeuchtung. Die genaue Temperaturführung muss verhindern, dass die Polyolefin-Fasern schmelzen, weil für die gewünschte Durchlässigkeit und Abscheidefähigkeit der Schicht die morphologische Struktur der Fasern erhalten bleiben muss. on the other hand, the desired high wet strength of the layer and also the desired greatly reduced swelling of the layer during moisture penetration result. The precise temperature control must prevent the polyolefin fibers from melting, because the morphological structure of the fibers must be preserved for the desired permeability and separability of the layer.
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Claims (6)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE3204120A DE3204120C3 (en) | 1982-02-06 | 1982-02-06 | Porous support layer for a diatomaceous earth filter cake formed by floating and process for its production |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CH661668A5 true CH661668A5 (en) | 1987-08-14 |
Family
ID=6154985
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CH619/83A CH661668A5 (en) | 1982-02-06 | 1983-02-03 | POROUS SUPPORT LAYER FOR A KIESELGUR FILTER CAKE formed by precoat and METHOD FOR THE PRODUCTION THEREOF. |
Country Status (7)
| Country | Link |
|---|---|
| CH (1) | CH661668A5 (en) |
| DE (1) | DE3204120C3 (en) |
| ES (1) | ES8403736A1 (en) |
| FR (1) | FR2521029B1 (en) |
| GB (1) | GB2115028B (en) |
| IE (1) | IE53885B1 (en) |
| IT (1) | IT1167072B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE3802816A1 (en) * | 1988-01-30 | 1989-08-10 | Seitz Filter Werke | Candle-shaped filter element, filter candle |
| DE10229291A1 (en) * | 2002-06-29 | 2004-02-05 | E. Begerow Gmbh & Co | Filter material, especially in the form of a depth filter layer |
| DE10346256B3 (en) * | 2003-09-24 | 2004-10-21 | E. Begerow Gmbh & Co | Production of filter material, especially deep filter layer, with predetermined number of natural fibers, e.g. cellulose, includes adding specific enzyme to suspension to convert each toxic polysaccharide to nontoxic or less toxic product |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| BE494548A (en) * | 1949-03-15 | |||
| CH313369A (en) * | 1951-12-24 | 1956-04-15 | Seitz Werke Gmbh | Process for the production of filter bodies with increased strength from fibrous or granular materials |
| GB1362344A (en) * | 1971-07-23 | 1974-08-07 | Gulf Research Development Co | Paper product and process for production thereof |
| GB1411776A (en) * | 1972-11-21 | 1975-10-29 | Mitsubishi Paper Mills Ltd | Method for producing a non-woven fabric |
| US4156628A (en) * | 1976-01-28 | 1979-05-29 | Hercules Incorporated | Preparation of hydrophilic polyolefin fibers for use in papermaking |
| US4084949A (en) * | 1975-11-06 | 1978-04-18 | The Dexter Corporation | Surgical face mask filtering medium |
| IT1074822B (en) * | 1977-01-21 | 1985-04-20 | Montedison Spa | PREPARATION OF FILTERS WITH THE USE OF SYNTHETIC FIBERS |
| IT1105843B (en) * | 1978-01-13 | 1985-11-04 | Munari Giovanni | PROCEDURE FOR THE MANUFACTURE OF WATERPROOF AND HEAT-SEALABLE PAPER OR CARDBOARD IN A CONTINUOUS MACHINE |
| JPS5841083B2 (en) * | 1978-10-05 | 1983-09-09 | 日産自動車株式会社 | How to recycle water-soluble cutting fluid |
| GB2047295B (en) * | 1979-04-19 | 1983-01-06 | Montedison Spa | Separators for lead acid accumulators |
-
1982
- 1982-02-06 DE DE3204120A patent/DE3204120C3/en not_active Expired - Fee Related
-
1983
- 1983-02-03 GB GB08302913A patent/GB2115028B/en not_active Expired
- 1983-02-03 CH CH619/83A patent/CH661668A5/en not_active IP Right Cessation
- 1983-02-04 FR FR8301783A patent/FR2521029B1/en not_active Expired
- 1983-02-04 IE IE222/83A patent/IE53885B1/en unknown
- 1983-02-04 IT IT47672/83A patent/IT1167072B/en active
- 1983-02-04 ES ES519547A patent/ES8403736A1/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| DE3204120A1 (en) | 1983-08-18 |
| ES519547A0 (en) | 1984-04-16 |
| GB8302913D0 (en) | 1983-03-09 |
| IT1167072B (en) | 1987-05-06 |
| ES8403736A1 (en) | 1984-04-16 |
| IT8347672A0 (en) | 1983-02-04 |
| GB2115028B (en) | 1985-08-07 |
| FR2521029A1 (en) | 1983-08-12 |
| GB2115028A (en) | 1983-09-01 |
| FR2521029B1 (en) | 1986-01-31 |
| IE53885B1 (en) | 1989-03-29 |
| IE830222L (en) | 1983-08-06 |
| DE3204120C3 (en) | 1994-12-22 |
| DE3204120C2 (en) | 1986-03-13 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PFA | Name/firm changed |
Owner name: SEITZ-FILTER-WERKE GMBH & CO. |
|
| PL | Patent ceased | ||
| AEN | Scope or validity of the patent modified |
Free format text: DAS PATENT IST AM 04.06.1998 GESTUETZT AUF DAS AM 08.05.1998 EINGEREICHTE WIEDEREINSETZUNGSGESUCH AUF GRUND VON ART. 47 PATG WIEDER IN KRAFT GESETZT WORDEN. |
|
| PL | Patent ceased |