EP1595997A1 - Machine for washing fibrous suspensions - Google Patents

Machine for washing fibrous suspensions Download PDF

Info

Publication number
EP1595997A1
EP1595997A1 EP04105734A EP04105734A EP1595997A1 EP 1595997 A1 EP1595997 A1 EP 1595997A1 EP 04105734 A EP04105734 A EP 04105734A EP 04105734 A EP04105734 A EP 04105734A EP 1595997 A1 EP1595997 A1 EP 1595997A1
Authority
EP
European Patent Office
Prior art keywords
machine
drum
flexible belt
disposed
laminar body
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Withdrawn
Application number
EP04105734A
Other languages
German (de)
English (en)
French (fr)
Inventor
Giancarlo Dal Maso
Flavio Magaraggia
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Comer Industries SpA
Original Assignee
Comer SpA
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 Comer SpA filed Critical Comer SpA
Publication of EP1595997A1 publication Critical patent/EP1595997A1/en
Withdrawn legal-status Critical Current

Links

Images

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
    • D21D5/06—Rotary screen-drums
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
    • D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
    • D21C9/18—De-watering; Elimination of cooking or pulp-treating liquors from the pulp

Definitions

  • the present invention is about a machine for washing the cellulose fibre which is used in paper manufacture.
  • the cellulose fibre has to be separated from the pollutant particles present therein, which are particularly relevant when the feedstock is for instance waste paper.
  • Such separation is obtained with the aid of particular machines for washing fibrous suspensions which, although in their different specific embodiments, all substantially consist of a pair of drums, of which at least a driven one, around which a flexible belt provided with through holes is wound as a loop ring.
  • the pair of drums comprises a grooved drum, provided with a plurality of mutually parallel circumferential grooves, and a smooth drum, provided with a scraper under which a container for collecting the washed cellulose fibre is disposed.
  • the cellulose fibre is dispersed, together with the pollutant substances, in a solution based on water contained inside a container.
  • the container communicates with a head box whose outlet mouth is disposed beneath the flexible belt, parallel to the drums axis, and it is turned toward the area in which the flexible belt begins to wind on the grooved drum.
  • the fibrous suspension which exits from the outlet mouth of the head box penetrates between the belt and the grooved drum, remaining adherent therein and turning together with said drum in the winding portion of the flexible belt.
  • the suspension due to the centrifugal force induced by the rotation of the drum, releases water and the impurities, normally of smaller size with respect to the cellulose fibres, which pass in the through holes of the flexible belt and are collected on the outside.
  • the fibrous suspension is set free from water and from the impurities contained therein under the effect of the centrifugal force induced by the rotation around the drum, which drives the water in the through holes of the flexible belt.
  • the cellulose fibre which remains adherent to the inner part of the flexible belt is conveyed to the second smooth drum, where it undergoes a compression between the cylinder surface and the belt surface, allowing the elimination by squeezing of a further quantity of water.
  • the detached fibre is collected by gravity inside an underneath container, from which it is then extracted by means of an auger that conveys it to the subsequent utilizations.
  • a first inconvenience is due to the fact that, in the zone upstream the winding point of the belt around the drum, even many of the shortest cellulose fibres pass through the holes of the flexible belt together with the fluid and the impurities contained in the suspension, thus being dispersed.
  • Said speed difference generates the grazing of the fibre mass against the surface of the belt and causes priming of turbulent movements which cause the passage of the shortest fibres, together with the impurities, through the belt holes.
  • Another acknowledged inconvenience is due to the fact that, always because of the turbulent movement to which the fibrous suspension penetrating between the flexible belt and the drum is submitted, the shortest cellulose fibres tend to pass through the belt holes even in the zone immediately downstream the contact line between the belt and the drum, with further losses of feedstock.
  • a further inconvenience is due to the fact that, in the machines of known type, it is not possible to modify the characteristics of speed and thickness of the fluid flow outgoing from the head box, unless the pressure above the head box, and thus the throughput, is changed.
  • washing machines of known type produce a considerable quantity of water polluted by the impurities extracted by the washed suspension, which have to be properly treated in depurators before being eventually reused in the productive cycle.
  • the present invention intends to eliminate the aforementioned inconveniences. It is a first object of the invention to provide for a machine for washing the cellulose fibre which allows to reduce the quantity of shortest cellulose fibres that are eliminated, together with the impurities, passing in the through holes of the flexible belt during the washing process.
  • Not the least object of the invention is to provide for a machine for washing the cellulose fibre which allows to reduce the quantity of water to be purified, polluted by the impurities extracted by the suspension.
  • the presence of a conveyor disposed between the head box and the contact line between the belt and the drum allows the fibrous suspension to undergo a gradual acceleration, avoiding that a turbulent movement, typical of the known embodiments, is created therein, which generates the discharge of the shortest cellulose fibres through the belt holes, together with the impurities.
  • the presence of the conveyor allows the suspension to be conveyed between the drum and the belt without the turbulent movements which, in the cited known embodiments, determine the loss of the shortest cellulose fibres through the belt holes.
  • the suspension to be treated arrives in the contact zone with the drums with the same speed of the belt and thus, being null the suspension-belt relative speed, no mutual grazing is generated.
  • the machine of the invention is shown in Figures 1 and 2, where it is generally indicated with numeral 1 , and it is adapted for washing fibrous suspensions S composed by cellulose fibres and pollutant agents dispersed in a liquid.
  • It comprises a frame 2 which supports a pair of cylindrical drums 3, 4 with substantially parallel and mutually spaced axes, between which a flexible belt 5 provided with through holes 6 is wound as a loop ring.
  • Conveying means 7 carry the fibrous suspension S to be washed at the zone 8 of incipient contact between the flexible belt 5 and the first drum 3 of the pair of drums 3, 4.
  • the first drum 3 has a plurality of circumferential grooves 3a, while the second drum 4 has a smooth surface 4a.
  • Driving means 9 comprising a first pulley 17 keyed to the motor 18, a second pulley 19 keyed to the grooved drum 3 and a transmission belt 20 wound between the aforementioned pulleys 17, 19, put in rotation the first drum 3 to move forward the flexible belt 5 in the direction indicated by the arrow 21.
  • the driving means could be also of other kind and they could be differently connected to one or even both drums.
  • the cellulose fibres contained in the fibrous suspension S are transferred from the flexible belt 5 on the lateral surface 4a of a second drum 4, which is part of the pair of drums 3, 4 equipping the washing machine 1, at which collecting means 11 of said fibres are present.
  • said collecting means 11 comprise a scraper 24 put in contact with the lateral surface 4a of the drum 4 and a container 25 for collecting the detached fibres, placed under the scraper 24.
  • the container 25 for collecting the washed cellulose fibre is internally provided with extraction means, which preferably but not necessarily consist of an auger 26 for conveying said fibre to the subsequent utilizations.
  • the conveying means 7 comprise:
  • the flow conveyor 15 comprises a laminar body 16 which has a shaped surface, turned toward the flexible belt 5, in which, starting from the inlet edge 16a disposed downstream the outlet mouth 14 of the head box 12, a bent portion 16c with the convexity turned toward the flexible belt 5 is present, followed by a straight portion 16d which ends with an outlet edge 16b disposed at the point 8 of incipient contact between the grooved drum 3 and the flexible belt 5.
  • the straight portion 16d of the laminar body 16 is substantially parallel disposed with respect to the flexible belt 5.
  • opening adjustment means 26 which consist of a sliding blade 27 disposed on the width of the conveying conduit 13 and provided on one side with screw means 28 to fix the head box 12 to the conveying conduit 13.
  • the laminar body 16 is joined to the sliding blade 27 of the above described conveying conduit 14, so that the displacement of the latter generates the sliding of the laminar body 16 in order to maintain its inlet edge 16a always at the same distance from the outlet mouth 14 of the conveying conduit 13.
  • the sliding blade 27 surface turned toward the opposite side of the flexible belt 5 is inclined with respect to the belt 5 at an angle ⁇ having double amplitude with respect to the inclination angle ⁇ of the corresponding surface of the laminar body 16, it too being turned toward the opposite side of the flexible belt 5.
  • the laminar body 16 surface turned toward the opposite side of the flexible belt 5 abuts, at its intermediate point 31, against a support structure 32 fixed to the conveying means 7.
  • Said surface is shaped so that its sliding on the support structure 32, because of the opening adjustment of the outlet mouth 14 of the conveying conduit 13, takes place according to a trajectory which allows the surface turned toward the flexible belt 5 to remain constantly parallel to said belt.
  • screw means 28 to fix the sliding blade 27 to the conveying conduit 13
  • they comprise a plurality of screws 33, each of them being provided with a control wheel 34, passing through the slot obtained in the sliding blade 27 and being screwed in a corresponding threaded hole obtained in the conveying conduit 13.
  • the flow conveyor 15 is furthermore provided with side shoulders 35, applied to the laminar body 16, able to laterally contain the fibrous suspension S which slides on its surface.
  • the machine 1 further comprises thrust elastic means 36 put in contact with the outer surface of the flexible belt 5, on the opposite side with respect to the laminar body 16, able to generate a slight pressure on the belt 5 to allow an initial squeezing of the fibrous suspension S against the surface of the laminar body 16.
  • the machine could be provided with a single collecting container in which either the liquid coming from the first drum or that coming from the second drum is indifferently conveyed.
  • the flexible belt 5 moves forward in the counterclockwise direction shown by the arrow 21, being put in motion by friction by the grooved drum 3 and being wound on the second drum 4 which, on the contrary, is idle and it is supported by a central shaft.
  • the fibrous suspension S exits from the head box 12 through the conveying conduit 13, it is guided by the first bent portion 16c of the laminar body 16 and, after being passed through the straight portion 16d of the laminar body 16, where it undergoes an acceleration that makes it to have the same advancement speed of the flexible belt 5, it enters in contact between the drum 3 and the flexible belt 5.
  • the presence of the elastic means 36 promotes already in this stage a first slight squeezing of the fibrous suspension S, which allows the longest fibres to reach the surface near the belt 5, generating a grid that avoid the shortest fibres to pass outwardly through the holes 6 obtained in the flexible belt 5 and thus being dispersed.
  • the fibrous suspension S penetrates between the grooved surface 3a of the first drum 3 and the flexible belt 5, passing through the portion wound on the grooved drum 3 of said belt; in this way, the fibrous suspension S, being disposed inside the grooves 3a obtained on the drum 3, undergoes a centrifugation action which allows to eliminate water and the pollutant substances contained therein.
  • the washed cellulose fibre remains adherent to the inner surface of the lower run 5a of the flexible belt 5, which conveys it in contact with the lateral surface 4a of the second drum 4, where it undergoes a further loss of water by the compression between the surface 4a of the second drum 4 and the flexible belt 5.
  • the water discharged through the holes 6 of the flexible belt 5 is collected in a second tank 23 and sent therefrom to the outside of the machine 1.
  • the liquid contained in the first collecting tank 22 has to be depurated, the liquid contained in the second collecting tank 23 can be directly used, since the very low quantity of pollutant substances contained therein, in other processes of the paper mill.
  • the cellulose fibre then reaches the upper part of the second drum 4, where it is put in contact with the scraper 24 which detaches it from the surface 4a of the drum 4 to make it fall by gravity inside the collecting means 11, from where the auger 26 provides for laterally sending it away from the machine 1.
  • the adjustment means 26, consisting of the previously described sliding blade 27, are joined to the laminar body so that the displacement of the blade 27 is followed by a sliding of the laminar body 16 on the support structure 32, in order that the surface of the laminar body 16 is maintained always parallel to the surface of the belt 5, to warrant a correct sliding of the fibrous suspension S.
  • the first cylindrical drum 37 is disposed at a higher level with respect to the second drum 39, so that the upper and lower rectilinear portions of the flexible belt 40 are inclined.
  • Such configuration allows to reduce the water quantity that is ejected upwardly under the effect of the centrifugal force, in the direction indicated by the arrow 41, thus avoiding that it can soak again the just squeezed fibres conveyed in the collecting tank 42.
  • the positioning of the first drum 37 at a higher level with respect to the previously described embodiment 1 allows to increase the capacity of the water and pollutant substances collecting tank 43, avoiding that the head 44 is put in contact with the drum 37.
  • the water coming from the first drum 37 by the effect of the centrifugation of the fibrous suspension S represents about the 80% of the water contained in the suspension S.

Landscapes

  • Engineering & Computer Science (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Wood Science & Technology (AREA)
  • Mechanical Engineering (AREA)
  • Paper (AREA)
  • Polysaccharides And Polysaccharide Derivatives (AREA)
EP04105734A 2004-05-10 2004-11-12 Machine for washing fibrous suspensions Withdrawn EP1595997A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IT000114A ITVI20040114A1 (it) 2004-05-10 2004-05-10 Macchina per il lavaggio di sospensioni fibrose
ITVI20040114 2004-05-10

Publications (1)

Publication Number Publication Date
EP1595997A1 true EP1595997A1 (en) 2005-11-16

Family

ID=34929851

Family Applications (1)

Application Number Title Priority Date Filing Date
EP04105734A Withdrawn EP1595997A1 (en) 2004-05-10 2004-11-12 Machine for washing fibrous suspensions

Country Status (6)

Country Link
US (1) US20050247423A1 (ko)
EP (1) EP1595997A1 (ko)
JP (1) JP2005320672A (ko)
KR (1) KR20050107731A (ko)
CN (1) CN1696399A (ko)
IT (1) ITVI20040114A1 (ko)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011001668A (ja) * 2009-06-22 2011-01-06 Voith Patent Gmbh 洗浄機用ヘッドボックス
CN103556520B (zh) * 2013-11-22 2016-01-13 广东理文造纸有限公司 一种用于面浆净化的高速清洗装置

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1398950A (en) * 1972-11-17 1975-06-25 Andritz Ag Maschf Liquid extraction machine having an imput system
EP0251787A1 (en) * 1986-07-03 1988-01-07 The Black Clawson Company Apparatus and method for thickening pulp and paper stock
EP0369611A2 (en) * 1988-10-28 1990-05-23 The Black Clawson Company Apparatus for thickening pulp and paper stock
DE4105803A1 (de) * 1991-02-23 1992-08-27 Voith Gmbh J M Entwaesserungseinrichtung fuer suspensionen

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10140800A1 (de) * 2001-08-20 2003-03-06 Voith Paper Patent Gmbh Vorrichtung zur Behandlung einer Faserstoffbahn

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB1398950A (en) * 1972-11-17 1975-06-25 Andritz Ag Maschf Liquid extraction machine having an imput system
EP0251787A1 (en) * 1986-07-03 1988-01-07 The Black Clawson Company Apparatus and method for thickening pulp and paper stock
EP0369611A2 (en) * 1988-10-28 1990-05-23 The Black Clawson Company Apparatus for thickening pulp and paper stock
DE4105803A1 (de) * 1991-02-23 1992-08-27 Voith Gmbh J M Entwaesserungseinrichtung fuer suspensionen

Also Published As

Publication number Publication date
US20050247423A1 (en) 2005-11-10
CN1696399A (zh) 2005-11-16
KR20050107731A (ko) 2005-11-15
JP2005320672A (ja) 2005-11-17
ITVI20040114A1 (it) 2004-08-10

Similar Documents

Publication Publication Date Title
US4399028A (en) Froth flotation apparatus and method
US7807020B2 (en) Method for degassing and supplying a fibrous suspension to a headbox or a filter device and degassing device
US4310424A (en) Apparatus and method for removing suspended solids from a stream
JP2002539967A (ja) ポリオレフィンプラスチックシート材料のリサイクル装置
SE537117C2 (sv) Anordning för tvåstegssilning av massa med två stationära cylindriska silorgan
EP1595997A1 (en) Machine for washing fibrous suspensions
US5224603A (en) Apparatus for treating fiber suspension
US8950584B2 (en) Apparatus for screening fibrous suspensions
SE506804C2 (sv) Sätt och anläggning för återvinning av olika komponenter i flerskiktsmaterial
US7461744B2 (en) Apparatus for separating fibers from reject material
NO169855B (no) Sorterer for fibersuspensjoner
NO802822L (no) Fremgangsmaate og apparat for vasking av fibermasse
US3698649A (en) Screening apparatus
FI84191C (fi) Foerfarande och anordning foer behandling av fibersuspension
US3705099A (en) Separating means and method
WO1999047277A9 (en) Apparatus for separating unwanted contaminants from fibrous slurry
SE432563B (sv) Skivpress for kontenuerlig pressning av vattenhaltig massa
JPH07308598A (ja) スクリーン選別装置用ロータおよびスクリーン選別装置
CA2958679C (en) Method and device for separating two phases
JP6007372B2 (ja) チューブポンプの液体移送方法及び液体を移送する装置
JPH0140155B2 (ko)
SE511142C2 (sv) Anordning med spädvätsketillförsel för silning av fibersuspensioner
US4927529A (en) Method and apparatus for separating knots
JPS63249792A (ja) 未蒸解物を分離する方法及び装置
US229073A (en) Stephen m

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LU MC NL PL PT RO SE SI SK TR

AX Request for extension of the european patent

Extension state: AL HR LT LV MK YU

17P Request for examination filed

Effective date: 20060516

AKX Designation fees paid

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LU MC NL PL PT RO SE SI SK TR

17Q First examination report despatched

Effective date: 20070416

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Effective date: 20070510