Classifications

• • D—TEXTILES; PAPER
  • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
  • D21F—PAPER-MAKING MACHINES; METHODS OF PRODUCING PAPER THEREON
  • D21F1/00—Wet end of machines for making continuous webs of paper
  • D21F1/66—Pulp catching, de-watering, or recovering; Re-use of pulp-water
  • D21F1/80—Pulp catching, de-watering, or recovering; Re-use of pulp-water using endless screening belts
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D33/00—Filters with filtering elements which move during the filtering operation
  • B01D33/04—Filters with filtering elements which move during the filtering operation with filtering bands or the like supported on cylinders which are impervious for filtering
  • B01D33/042—Filters with filtering elements which move during the filtering operation with filtering bands or the like supported on cylinders which are impervious for filtering whereby the filtration and squeezing-out take place between at least two filtering bands
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D33/00—Filters with filtering elements which move during the filtering operation
  • B01D33/35—Filters with filtering elements which move during the filtering operation with multiple filtering elements characterised by their mutual disposition
  • B01D33/37—Filters with filtering elements which move during the filtering operation with multiple filtering elements characterised by their mutual disposition in parallel connection
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D33/00—Filters with filtering elements which move during the filtering operation
  • B01D33/44—Regenerating the filter material in the filter
  • B01D33/48—Regenerating the filter material in the filter by flushing, e.g. counter-current air-bumps
  • B01D33/50—Regenerating the filter material in the filter by flushing, e.g. counter-current air-bumps with backwash arms, shoes or nozzles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B30—PRESSES
  • B30B—PRESSES IN GENERAL
  • B30B9/00—Presses specially adapted for particular purposes
  • B30B9/02—Presses specially adapted for particular purposes for squeezing-out liquid from liquid-containing material, e.g. juice from fruits, oil from oil-containing material
  • B30B9/20—Presses specially adapted for particular purposes for squeezing-out liquid from liquid-containing material, e.g. juice from fruits, oil from oil-containing material using rotary pressing members, other than worms or screws, e.g. rollers, rings, discs
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B30—PRESSES
  • B30B—PRESSES IN GENERAL
  • B30B9/00—Presses specially adapted for particular purposes
  • B30B9/02—Presses specially adapted for particular purposes for squeezing-out liquid from liquid-containing material, e.g. juice from fruits, oil from oil-containing material
  • B30B9/24—Presses specially adapted for particular purposes for squeezing-out liquid from liquid-containing material, e.g. juice from fruits, oil from oil-containing material using an endless pressing band
  • B30B9/246—The material being conveyed around a drum between pressing bands
• • 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 relates to a concentrator press of the kind which comprises a pair rotatably drivable press rolls which are arranged for mutual coaction and which have apertured or perforated mantle surfaces for removing liquid from a liq ⁇ uid-saturated material to be concentrated and advanced between the press rolls, wherein each of the press rolls is embraced around a part of its periphery, including at least the region in which the roll acts on the material undergoing concentra ⁇ tion, by an endless filter-cloth web which also runs around at least one web direction changing roller located at a distance from its associated press roll and the not yet concentrated liquid-drenched material.
• Concentrator presses of the aforesaid kind are known from SU-A- 561 765 and are used to increase the dry solid contents of liq- uid-particle or liquid-fibre suspensions or liquid-rich parti ⁇ cle pulps or fibre pulps, such as for de-watering cellulose pulps, for instance.
• a large total hole area in the apertured or perforated mantle surfaces of the press rolls is therefore desirable from the aspect of capacity.
• the size of the perfora ⁇ tions in the mantle surfaces of the rolls can be increased, with subsequent improvement in the permeability of the rolls, by using filter-cloth webs that prevent the undesirable passage of particles or fibres, provided that this increase m the size of the holes does not impair the support afforded to the filter cloth.
• the filter-cloth webs move downwards and away from one another af- ter passing through the press nip and the concentrated material falls down into an underlying material transporter.
• the oo ⁇ ect of the present invention is to provide a novel and advantageous arrangement with which the aforesaid drawbacks are avoided to at least a substantial extent.
• the filter-cloth webs are caused to run generally parallel with one another downstream of the press nip, up to a concentrated mate- rial delivery station.
• This arrangement avoids re-wettmg of the concentrated material to a large extent.
• Further improve ⁇ ments are achieved in this respect in accordance with a pre ⁇ ferred embodiment of the invention in which the mutually paral ⁇ lel web sections extend upwards from the press rolls.
• the upper parts of the mutually parallel web sections are curved so as to deliver the concentrated material to one side of the press. This further reduces the risk of re-wetting the concentrated material and the material is obtained in the form of a coherent web of generally uniform thickness which can be subjected to a subsequent additional concentration stage for instance, in a simple and rational manner.
• Figs. 1 and 2 are schematic vertical cross-section views of a first and a second embodiment of an inventive concentrator press respectively.
• the concentrator press illustrated in Fig. 1 includes two press rolls 1 which are partially submerged in a trough 2, which in the illustrated case is assumed to contain a pulp sus- pension 3 that is to be concentrated or de-watered.
• the pulp suspension is delivered through an inlet 4 with the aid of a delivery pump, not shown.
• the press rolls 1 typically include perforated or apertured mantle surfaces 5 and are each partially embraced in the aper ⁇ tured region thereof by a respective individual endless filter ⁇ cloth web 6, 7, e.g. a wire cloth of suitable plastic material.
• a respective individual endless filter ⁇ cloth web 6, 7, e.g. a wire cloth of suitable plastic material As evident from Fig. 1, at least those parts of the mantle sur- faces 5 of the rolls 1 that are immersed in the pulp suspension are surrounded by an associated filter-cloth web.
• the roll trunnions are journalled in the trough end walls, where at least one trunnion 8 of each press roll is tubular and con ⁇ nected to a pump or some other subpressure source (not shown) for the purpose of removing liquid that has entered the inte ⁇ rior of the rolls 1.
• Seals 9 act on the sides of the press rolls 1 remote from the press nip between the rolls 1 in a re ⁇ gion where the roll mantle surfaces are covered by an associ ⁇ ated filter-cloth web 6, 7. Although not shown, corresponding seals seal against the end surfaces of the rolls 1, so as to close the trough 2 and enable a overpressure to be conveniently maintained in the trough and therewith assist removal of liquid from the pulp suspension 3 in the trough 2 and into the inte ⁇ rior of the rolls 1.
• Each of the filter-cloth webs 6, 7 partially surrounding the rolls 1 runs around a web direction changing or guide roller 10.
• the filter-cloth webs move upwards from the roll nip to the guide rollers 10 essentially parallel with one another in the direction of the arrows 11.
• the reference numeral 12 identifies web stretching or tensioning rollers that can be brought into abutment with the webs 6, 7, whereas the reference numeral 13 identifies spray nozzles with which the webs are sprayed clean.
• the press rolls 1 are rotated in mutually opposite directions so that the mutually parallel sections of the webs 6, 7 will move upwards at the same time as the pulp suspension is delivered to the trough 2 under an overpressure and a subpressure s gener ⁇ ated in the interior of the rolls 1.
• the suspension is there- with drawn by suction towards those areas of the roll mantle surface that are embraced by the filter-cloth webs and immersed in the trough 2 and transported to and through the roll nip and de-watered therein, wherewith water departs through the hollow trunnions 8.
• the de-watered pulp 14 is transported upwards be- tween the mutually parallel web sections to a delivery station in which guide scrapers 15 lead the concentrated pulp into a material transporter 16 situated above the press rolls 1 at a distance therefrom.
• At least one press roll may be movable to ⁇ wards and away from the other so as to enable the size of the press nip to be adjusted, and the filter-cloth webs 6, 7 may be provided with conventional web restraining means (not shown) for preventing lateral movement of the webs.
• the filter-cloth guide roller 10 is also movable in a vertical direction to enable tension in the web 6 to be adjusted.
• Two direction changing rollers 17, 18 and a guide roller 19 are provided for the web 7, whereby the web sections moving parallel with one another are curved to the left in the Figure, such as to deliver the concentrated pulp 14 in the form of a coherent web of generally uniform thickness to one side of the press.
• one of the direction changing rollers 17, 18 is also movable generally horizontally for adjusting the tension in the web 7.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Mechanical Engineering (AREA)
• Life Sciences & Earth Sciences (AREA)
• Wood Science & Technology (AREA)
• Paper (AREA)
• Treatment Of Fiber Materials (AREA)
• Filtration Of Liquid (AREA)
• Filtering Materials (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=20399823

Family Applications (1)

Country Status (7)

Families Citing this family (1)

Family Cites Families (1)

• 1995
  • 1995-10-13 SE SE9503591A patent/SE9503591L/xx not_active IP Right Cessation
• 1996
  • 1996-10-03 EP EP96935670A patent/EP0956132A1/de not_active Withdrawn
  • 1996-10-03 AU AU73496/96A patent/AU7349696A/en not_active Abandoned
  • 1996-10-03 WO PCT/SE1996/001249 patent/WO1997013572A1/en not_active Application Discontinuation
  • 1996-10-03 CA CA002234097A patent/CA2234097A1/en not_active Abandoned
  • 1996-10-03 JP JP9514974A patent/JPH11513313A/ja active Pending
• 1998
  • 1998-04-08 NO NO981640A patent/NO981640L/no unknown

Non-Patent Citations (1)

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