EP0294832B1 - Vorrichtung zum Sieben von Faserbrei - Google Patents

Vorrichtung zum Sieben von Faserbrei Download PDF

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Publication number
EP0294832B1
EP0294832B1 EP88109280A EP88109280A EP0294832B1 EP 0294832 B1 EP0294832 B1 EP 0294832B1 EP 88109280 A EP88109280 A EP 88109280A EP 88109280 A EP88109280 A EP 88109280A EP 0294832 B1 EP0294832 B1 EP 0294832B1
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EP
European Patent Office
Prior art keywords
grooves
screen
rotor
plane
perforations
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.)
Expired - Lifetime
Application number
EP88109280A
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English (en)
French (fr)
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EP0294832A3 (en
EP0294832A2 (de
Inventor
Frey Frejborg
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Ahlstrom Corp
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Ahlstrom Corp
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Filing date
Publication date
Priority claimed from US07/061,594 external-priority patent/US4880540A/en
Application filed by Ahlstrom Corp filed Critical Ahlstrom Corp
Publication of EP0294832A2 publication Critical patent/EP0294832A2/de
Publication of EP0294832A3 publication Critical patent/EP0294832A3/en
Application granted granted Critical
Publication of EP0294832B1 publication Critical patent/EP0294832B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21D—TREATMENT OF THE MATERIALS BEFORE PASSING TO THE PAPER-MAKING MACHINE
    • D21D5/00—Purification of the pulp suspension by mechanical means; Apparatus therefor
    • D21D5/02—Straining or screening the pulp
    • D21D5/023—Stationary screen-drums
    • D21D5/026—Stationary screen-drums with rotating cleaning foils
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21D—TREATMENT OF THE MATERIALS BEFORE PASSING TO THE PAPER-MAKING MACHINE
    • D21D5/00—Purification of the pulp suspension by mechanical means; Apparatus therefor
    • D21D5/02—Straining or screening the pulp
    • D21D5/16—Cylinders and plates for screens

Definitions

  • the present application relates generally to apparatuses for screening fiber suspensions of consistency between 0.3% up to 6%, and in particular, to a screening apparatus for screening papermaking pulp containing wood portions and other undesirable particles of various sizes and types, according to the preamble of the claim 1.
  • a screening apparatus for screening papermaking pulp containing wood portions and other undesirable particles of various sizes and types, according to the preamble of the claim 1.
  • Such an apparatus is known from the EP-A-0 206 975.
  • a pulp screening apparatus which comprises a vessel, a cylindrical screen within the vessel, a rotating element moving in the vicinity of the screen at a predetermined speed, an inlet for the unscreened pulp, an outlet for the accept screened pulp in the vessel, another outlet for the reject, in operative communication with the screen.
  • the rotating element has a contour surface with grooves formed of a first bottom plane parallel to the envelope surface of the screen, an inclined plane and a side plane.
  • the side plane is essentially perpendicular to the first bottom plane.
  • the inclined plane forms an angle between 30°-60° with the first plane.
  • the upper plane is parallel to the first plane.
  • the screen is also provided with grooves.
  • pulp is produced by cooking wood which separates the wood into fibers. Due to the different properties of the wood even from the same tree, some of the fibers do not separate and are dispersed as fiber bundles usually called debris, shives or slivers which form the reject. There are also other impurities, such as bark, which must be removed.
  • the screen must separate the undesirable impurities and debris called the rejects from the accept portion. In order to avoid substantial losses of fibers which could be carried over together with the debris in the reject portion, it is necessary to remove the impurities efficiently and selectively.
  • the stock enters at the inlet end of the screening zone and travels in an angle along the screening surface with the acceptable portions of the stock passing through the screening surface and with the rejectable portions of the pulp traveling along the screening surface essentially in a spiral path and passing out of the screening zone at the reject end.
  • the liquid that accompanies the fibrous stock passes through the screening surface more easily than the fibers. Therefore, as the stock travels along the screening zone, it tends to crease in consistency which means that the fiber-to-water ratio is increased. If this ratio increases too much, the screening process will be slowed down or will be even interrupted. In order to prevent this slow-down or interruption, it has been common practice to add more water to the stock to replace some of the water which has passed through the screening surface so as to maintain a satisfactory screening consistency on the inlet side.
  • Another method used to maintain the screening consistency on the inlet side is to intentionally feed the apparatus with over-diluted stock so that the excess water at the inlet will be sufficient to allow for continuity of screening throughout the screening zone.
  • both methods of adding more water during the screening or initially over-diluting the stock have undesirable effects such as diminishing the capacity of the screen by the amount of water added.
  • Pulps of different consistencies require screens with different contours. Different contours are also required with pulp suspensions having different physical properties and for different applications.
  • An object of the present invention is to separate the long fibers from slives and debris efficiently and selectively. This object is solved by the features of the claim 1.
  • a screening apparatus which may be operated under smooth flow as well as under more turbulent flow conditions. There is maintained the desired screening efficiency without adding water during the screening operation and without using initially an overly diluted stock.
  • screening apparatus which according to the invention can operate at pulp feed consistencies between 0.3% up to 6%.
  • the rotor may be used with a variety of contoured screens, for a variety of pulp suspensions, which may provide the pumping effect required with the low consistency suspensions and which may provide the turbulence required for higher consistency stocks.
  • the pulp flows from the outside to the inside of the screen and the contoured surface of the screen is on the outside of the screen.
  • the screening apparatus includes a pressurized housing 1, a cylindrical screen 3 positioned within the housing, a rotor 4 mounted within the screen on the upper part of a rotatable, vertical shaft 5.
  • the housing has an inlet 6 for allowing unscreened pulp suspension to be introduced into a chamber 7 in the upper part of the housing, an outlet 8 for accepted (screened) stock, a reject chamber 19 and an outlet 9 for rejected stock in the lower end.
  • a screening chamber 12 is formed between the cylindrical screen and the rotor.
  • Numeral 15 designates the accept chamber.
  • Numeral 2 designates a removable cover for the housing and numeral 11 designates a plate closing the upper end of the screening chamber.
  • the housing includes an additional structure 17 which, together with a flange 18, forms a partition between the second chamber and a third chamber 19 which is the reject chamber in the bottom part of the housing.
  • the stock inlet 6 communicates directly with the first chamber
  • the accept outlet 8 communicates directly with the second chamber
  • the reject outlet 9 communicates directly with the third chamber.
  • axial bars or foils 20 which extend along at least a portion of the length of the rotor are mounted on a support adjacent the inner surface of the rotor.
  • a plate 21 closes the lower end of the rotor. Openings 22 in the lower end of the rotor drum 23 provide communication between the space inside the rotor and the reject chamber.
  • the screen plate 3 has a contoured surface. According to one embodiment, shown in Fig. 2, the cylindrical screen plate has grooves 24 in the inlet surface. Also the outside and the inside surfaces of the rotor are contoured with grooves 25 and 26, but the rotor could have only one contour surface facing the screen. The contour surface is not necessarily continuous.
  • the grooves 25 on the screen side of the rotor are formed of a bottom plane 27 and two side planes 28 and 29.
  • the grooves 26 on the inlet side of the rotor are likewise formed by a bottom plane 30 and two side planes 31 and 32.
  • the bottom planes 27 and 30 are generally perpendicular to the side planes 32 and 29.
  • the side planes 28 and 31 are generally inclined with respect to the cylindrical outer and inner surfaces.
  • the angle ⁇ is formed between upper plane 33 and the inclined plane 28 and is in this embodiment between 5° and 60°.
  • the angle ⁇ is formed between the envelope surface 34 and side plane 31 and is between 10° and 60°.
  • the symbol H1 designates the distance between the bottom plane 27 and the upper plane 33 in the outer surface of the rotor and may be between 1,59 mm (1/16 inch) and 50,8 mm (2 inches).
  • the symbol H2 designates the distance between the bottom plane 30 and the envelope surface 34 in the inlet side of the rotor and may be between 1,59 mm (1/16 inch) and 50,8 mm (2 inches).
  • the symbols B1 and B2 designate the width of the bottom planes 27 and 30 in the outer and inner surface respectively of the rotor and may be as low as 3,18 mm (1/8 inch) and as long as 50,8 mm (2 inches).
  • the rotor 23 has a plurality of perforations 35 extending along a portion (L in Fig. 1) of its axial length beginning from its upper end and a size allowing fibrous stock to pass through the rotor but preventing foreign objects of larger size than the inlet openings 36 of the perforations from entering the screening zone 12.
  • the inlet openings of the perforations are positioned in the bottom plane of the grooves 26 on the inlet side of the rotor and the discharge openings 37 are positioned either on the upper plane 33 of the outlet surface of the rotor or on the inclined plane 28 or on the bottom plane 27.
  • the perforations in the rotor are either cylindrical or preferably slotted in section.
  • the discharge opening of the perforations is preferably larger than the inlet opening.
  • the grooves as well as the perforations of the rotor are larger than the grooves and the perforations of the screen in the embodiment of Fig. 2 but this in not essential.
  • the rotor may also be constructed of profiled bars which, when assembled, form longitudinal openings therebetween which then constitute the perforations of the rotor.
  • the profiled bars may be represented by the dotted lines drawn through the openings of the rotor as shown in Fig. 2.
  • the inclined side plane on each surface of the rotor can be the leading side plane or the trailing plane of the groove in relation to the direction of the rotation of the rotor in the embodiment of Fig. 2.
  • the rotor may rotate in different directions, that is, clockwise as shown in Fig. 2, for high efficiency, or counterclockwise to achieve high capacity.
  • the grooves 25 and 26 may be located in relation to each other as shown in Fig. 2, that is the inclined planes being the downflow sides of the grooves. However, either or both of the grooves 25 and 26 may be formed so that the perpendicular planes 29, 32 are the downflow sides of the grooves. It is also possible that the grooves are so formed that every second groove has as its downflow side the inclined plane and the others have the perpendicular plane. Also it is possible to arrange the grooves in groups so that a certain group of grooves has as its downflow side the inclined planes and the next group of grooves the perpendicular planes.
  • pulp suspension is supplied to the first chamber 7 in the upper end of the apparatus through inlet 6 and flows into the rotor 4.
  • the fibrous stock flows through the perforations in the rotor to the screening chamber and particles larger than the perforations will not pass through the perforations of the rotor.
  • the large cross-sectional area of the rotor allows heavy foreign material to settle for rejection through the openings 22 at the lower end of the rotor and allows the pulp suspension to flow in an almost radial direction towards the inner surface of the rotor.
  • the stock which enters the screening chamber is set into circumferential motion by the rotor and subjected to high-intensity pulses and turbulence when flowing over essentially in a direction perpendicular to the grooves on the screen surface.
  • the angle between the direction of the grooves and the axial direction of the cylinder of the screen plate may be from 0° to 45°.
  • the acceptable fibers pass through the perforations in the screen to be collected in the chamber 15 surrounding the screen and are removed through the outlet 8 as accepted stock. Any stock not passing through the perforations of the rotor or the screen is collected in the chamber 19 in the lower end of the housing and is discharged through the outlet 9 as rejects.
  • the screening chamber 12 between the rotor and the screen can be as narrow as 1 mm and as large as 50 mm.
  • the screening chamber When the screening chamber is narrow, between 1 and 3 mm, an effective hydrodynamic interaction between the grooved surfaces of the rotor and the screen facing each other is achieved, and advantageous conditions for the screening are provided. This also permits the screen to efficiently handle stock of high consistency, up to 6%.
  • the groove in the screen is formed of a bottom plane 40 which is substantially parallel with the envelope surface 42 of the screen surface, an upstream side plane 44 as seen standing from the bottom of the groove and a downstream side plane 45.
  • the angle ⁇ between the envelope surface of the screen surface and the upstream side plane 44, or in other words between the plane tangenting the envelope surface of the screen surface close to this side plane and this side plane is approximately 90° and the angle ⁇ between the envelope surface of the screen surface and the downstream side plane 45 is 5°-60°.
  • the angle ⁇ is 5°-60° and the angle ⁇ is 90°.
  • the perforations of the screen plate are disposed on the bottom planes 40 of the grooves.
  • the grooves 52 are U-shaped, and both side planes 44 and 45 are substantially perpendicular to the envelope surface 42 of the screen surface.
  • the screen surface is undulant and both sides 44 and 45 of the grooves 52 are inclined with regard to the envelope surface 42 of the screen surface.
  • the surface of the rotor which does not face the screen is not necessarily grooved and it is not necessary that the entire surface of the rotor be grooved.
  • the inlet side of the rotor also may have a contour surface, for instance, the contour of the screen as shown in Figs. 3-8.
  • the grooves have two side planes, a bottom plane and an upper plane, one side plane is perpendicular to the envelope surface of the screen and the other side plane is curved, convex or concave with respect to the envelope surface.
  • Fig. 8 the sides of the grooves have an inverted V-shape configuration.
  • Figs. 1 and 2 show an apparatus intended for outflow operation
  • the apparatus according to Fig. 9 may be readily adapted for inflow configuration according to which the pulp is fed into the outer surface of the rotor, goes through the perforations inwardly, flows into the screening chamber. Thereafter the accept portion passes through the finer perforations of the screen into the accept chamber and the remaining reject portion in the screening chamber moves towards the reject chamber. This operation is particularly advantageous when large dirt type particles are to be removed.
  • Another advantage of the apparatus according to the present invention is that it may be retrofitted and used with conventional screen housings, resulting in major capital savings.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Paper (AREA)

Claims (27)

1. Siebvorrichtung für Pulpe bestehend aus einem Gehäuse (1) mit einem Eintritt (6), durch den Faserstoff in dessen Innere geleitet werden kann, einem ersten Austritt (8), durch den der Gutstoff des gesiebten Faserstoffes daraus entfernt werden kann, einem zweiten Austritt (9) für den Spuckstoff, einem Sieb (3) mit einer konturierten Oberfläche innerhalb des genannten Gehäuses (1), einem Rotor (4), der sich mit einer vorgegebenen Geschwindigkeit in der Nähe des genannten Siebs (3) bewegt und mit dem genannten Sieb (3) eine ringförmige Siebkammer (12) bildet, bei welchem genannten Rotor (4) mindestens die dem Sieb (3) zugewandte Oberfläche teilweise konturiert ist, dadurch gekennzeichnet, daß mindestens die dem Sieb zugewandte Oberfläche des Rotors über mindestens einen Teïl der Länge der genannten Sïebkammer (12) mit einer Vïelzahl von Öffnungen (35) versehen ist, durch die Faserstoff in die genannte Siebkammer (12) eingegeben werden kann und die verhindern, daß unerwünschter Spuckstoff der Pulpe in die genannte Kammer (12) gelangt, wobei die genannte konturierte Oberfläche des Rotors (4) aus Rillen (25; 26) in den beiden Flächen derselben besteht.
2. Vorrichtung gemäß Anspruch 1, worin die genannten Rillen (25; 26) eine Grundfläche (27; 30) und zwei Seitenflächen (28, 29; 31, 32) haben, deren eine geneigt und die andere senkrechtgegenüber der Grundfläche (27; 30) ist, wobei die genannte geneigte Fläche einen Winkel zwischen 5° und 60° mit der Bodenfläche (27; 30) bildet.
3. Vorrichtung gemäß Anspruch 2, worin die genannte konturierte Oberfläche des Rotors (4) aus Rillen (25; 26) besteht, die genannten Rillen (25; 26) eine obere Fläche (33; 34), eine Grundfläche (27; 30) und zwei Seitenflächen (28, 29; 31, 32) haben, die eine Seitenfläche geneigt und die andere Seitenfläche senkrecht gegenüber der Grundfläche (27; 30) ist, wobei die genannte geneigte Fläche einen Winkel zwischen 5° und 60° mit der Grundfläche (27; 30) bildet.
4. Vorrichtung gemäß Anspruch 2, worin die Rillen (25; 26) des Rotors (4) eine Oberlaufseite und eine Unterlaufseite haben, die Unterlaufseite der Rillen (25; 26) des Rotors (4) geneigt gegen die Oberfläche des Rotors (4) ist und die Oberlaufseite im wesentlichen senkrecht zur Oberfläche des Rotors (4) ist.
5. Vorrichtung gemäß Anspruch 2, worin die Rillen (25; 26) des Rotors (4) eine Oberlaufseite und eine Unterlaufseite haben, die unterlaufseitige Seitenfläche der Rillen (25; 26) des Rotors (4) im wesentlichen senkrecht zur Grundfläche (27; 30) ist und die Oberlaufseite gegen die Oberfläche des Rotors (4) geneigt ist.
6. Vorrichtung gemäß Anspruch 1, worin der Rotor (4) Rillen (25; 26) auf beiden Oberflächen hat, die Öffnungen (35) einen Eintritt (36) haben und der Eintritt (36) der Öffnungen (35) im Bodenabschnitt (30) der Rillen (26) der Eintrittsseite von Rotor (4) angeordnet ist.
7. Vorrichtung gemäß Anspruch 2, worin die Öffnungen (35) einen Austritt (37) haben und der Austritt (37) in der geneigten Fläche der Rillen (25) der Austrittsseite von Rotor (4) angeordnet ist.
8. Vorrichtung gemäß Anspruch 2, worin die Öffnungen (35) einen Austritt (37) haben, der in der oberen Ebene (33) der Rillen (25) der Austrittsseite von Rotor (4) angeordnet ist.
9. Vorrichtung gemäß Anspruch 2, worin die Öffnungen (35) einen Austritt (37) haben, der in der Grundfläche (27) der Rillen (25) der Austrittsseite von Rotor (4) angeordnet ist.
10. Vorrichtung gemäß Anspruch 1, worin der Rotor (4) innerhalb des Siebs (3) angeordnet ist.
11. Vorrichtung gemäß Anspruch 1, worin die Innenfläche des Rotors (4) der Außenfläche des Siebs (3) zugewandt ist.
12. Vorrichtung gemäß Anspruch 1, worin der genannte Rotor (4) zylindrisch ist.
13. Vorrichtung gemäß Anspruch 1, worin der genannte Rotor (4) nicht zylindrisch ist.
14. Vorrichtung gemäß Anspruch 1, worin die Öffnungen (35) im Rotor (4) zylindrisch sind.
15. Vorrichtung gemäß Anspruch 1, worin die Öffnungen (35) im Rotor (4) nicht zylindrisch sind.
16. Vorrichtung gemäß Anspruch 1, worin die konturierte Oberfläche des Siebs (3) aus Rillen (24) mit Öffnungen besteht, die Rillen (25; 26) und die Öffnungen (35) des Rotors (4) größer sind als die Rillen und die Öffnungen des Siebs (3).
17. Vorrichtung gemäß Anspruch 1, worin das Sieb (3) eine zylindrische Siebplatte ist, die Rillen (24, 52) mit Öffnungen hat, die Öffnungen am Boden der Rillen (24, 52) sind, die Grundfläche (40) der Rillen parallel zur Mantelfläche (42) ist, die Rillen (24, 52) zwei Seitenflächen (44; 45) haben, die eine Seitenfläche der Rillen (24, 52) im wesentlichen senkrecht zur Mantelfläche (42) der Siebfläche ist und die andere Seitenfläche in bezug auf die genannte Mantelfläche (42) geneigt ist.
18. Vorrichtung gemäß Anspruch 17, worin die genannte Siebplatte (3) Rillen (24, 52) auf der Seite des in die Siebfläche versenkten Eintritts hat, die Siebplatte (3) eine Mantelfläche (42) hat, die Rillen (24, 52) durch eine oberlaufseitige Seitenfläche (44), vom Boden der Rillen (24, 52) aus gesehen, eine unterlaufseitige Seitenfläche (45) und eine Grundfläche (40) gebildet werden, welche Grundfläche (40) im wesentlichen parallel zur Mantelfläche (42) der Siebplatte (3) ist, die Rillen (24, 52) Öffnungen in der Grundfläche (40) haben, die oberlaufseitige Setenfläche (44) der Rillen (24, 52) im wesentlichen senkrecht zur genannten Mantelfläche (42) ist und die unterlaufseitige Seitenfläche (45) der Rillen (24, 52) einen Winkel zwischen 60° und 5° gegenüber der genannten Mantelfläche (42) bildet.
19. Vorrichtung gemäß Anspruch 18, worin in der genannten Siebplatte (3) die unterlaufseitige Seitenfläche (45) und die oberlaufseitige Seitenfläche (44) der Rillen (24, 52) über eine Fläche miteïnander verbunden sind, die im wesentlichen parallel zur genannten Mantelfläche (42) ist.
20. Vorrichtung gemäß Anspruch 10, worin das genannte Sieb (3) eine Eintrittsseite und eine Austrittsseite hat, der genannte Rotor (4) auf der Eintrittsseite des Siebs (3) plaziert ist; die konturierte Fläche des Siebs (3) ist auf der Innenseite des Siebs (3).
21. Vorrichtung gemäß Anspruch 11, worin das genannte Sieb (3) eine Eintrittsseite und eine Austrittsseite hat, der Rotor (4) auf der Eintrittsseite des Siebs (3) plaziert ist und die konturierte Fläche des Siebs (3) auf der Außenseite des Siebs (3) ist.
22. Vorrichtung gemäß Anspruch 17, worin die unterlaufseitigeseitenfläche (45) der Rillen (24, 52) im wesentlichen senkrecht zur Mantelfläche (42) der Siebfläche und die oberlaufseitige Seitenfläche (44) geneigt ist.
23. Vorrichtung gemäß Anspruch 1, worin die konturierte Fläche des Siebs (3) aus Rillen (24, 52) besteht und beide Seitenflächen (44; 45) der Rillen (24, 52) im wesentlichen senkrecht zur Mantelfläche (42) des Siebs (3) sind.
24. Vorrichtung gemäß Anspruch 1, worin das Sieb (3) eine zylindrische Siebplatte mit Rillen (24, 52) ist, die Öffnungen am Boden der Rillen (24, 52) sind, die Grundfläche (40) der Rillen (24, 52) parallel zur Mantelfläche (42) ist, di Rillen (24, 52) zwei Seitenflächen (44; 45) und eine obere Fläche haben, eine Seitenfläche der Rillen (24, 52) im wesentlichen senkrecht zur Mantelfläche (42) des Siebs (3) ist und die andere Seitenfläche in bezug auf die genannte Mantelfläche (42) gebogen ist.
25. Vorrichtung gemäß Anspruch 24, worin die genannte Seitenfläche konvex oder konkav in bezug auf die genannte Mantelfläche (42) ist.
26. Vorrichtung gemäß Anspruch 1, worin die Siebfläche wellenartig ist, das Sieb (3) Rillen (24, 52) hat und die beiden Seiten der Rillen (24, 52) in bezug auf die Mantelfläche (42) geneigt sind.
27. Vorrichtung gemäß Anspruch 1, worin die genannte konturierte Oberfläche des Rotors (4) durch voneinander getrennte konturierte Stäbe (20) gebildet werden.
EP88109280A 1987-06-11 1988-06-10 Vorrichtung zum Sieben von Faserbrei Expired - Lifetime EP0294832B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US61594 1987-06-11
US07/061,594 US4880540A (en) 1983-01-26 1987-06-11 Pulp screening apparatus

Publications (3)

Publication Number Publication Date
EP0294832A2 EP0294832A2 (de) 1988-12-14
EP0294832A3 EP0294832A3 (en) 1989-03-08
EP0294832B1 true EP0294832B1 (de) 1991-04-17

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Application Number Title Priority Date Filing Date
EP88109280A Expired - Lifetime EP0294832B1 (de) 1987-06-11 1988-06-10 Vorrichtung zum Sieben von Faserbrei

Country Status (5)

Country Link
EP (1) EP0294832B1 (de)
BR (1) BR8807561A (de)
DE (2) DE3862433D1 (de)
FI (1) FI882569A (de)
WO (1) WO1988009843A1 (de)

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US5200072A (en) 1990-08-16 1993-04-06 Ahlstrom Screen Plates Inc. Screen plates and methods of manufacture
CA2210877C (en) * 1995-02-03 1999-12-21 Hermann Finckh Maschinenfabrik Gmbh & Co. Fibre suspension pressure sorting machine and sieve for such pressure sorting machines
SE504657C2 (sv) * 1995-07-03 1997-03-24 Sunds Defibrator Ind Ab Tätningsanordning
ES2155410B1 (es) * 1999-08-24 2001-12-01 Perez Ernesto Pastor Depurador de pasta de papel.
FI20022055A (fi) * 2002-11-19 2004-05-20 Advanced Fiber Tech Aft Trust Menetelmä ja laite kuitususpension käsittelemiseksi
CN101171390B (zh) 2005-05-09 2011-04-13 纺织过滤材料股份有限公司 筛网筐及装配筛网筐的方法
WO2009062287A1 (en) 2007-11-14 2009-05-22 Filtration Fibrewall Inc. Screen basket

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102041705A (zh) * 2009-10-23 2011-05-04 安德里兹公司 用于处理纤维悬浮液的设备
CN102041705B (zh) * 2009-10-23 2014-12-24 安德里兹公司 用于处理纤维悬浮液的设备

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Publication number Publication date
FI882569A0 (fi) 1988-06-01
DE3862433D1 (de) 1991-05-23
FI882569A (fi) 1988-12-12
DE294832T1 (de) 1989-07-13
WO1988009843A1 (en) 1988-12-15
BR8807561A (pt) 1990-04-17
EP0294832A3 (en) 1989-03-08
EP0294832A2 (de) 1988-12-14

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