Press roll comb plate and related method

Patent metadata

Field	Value
Publication number	US-9803319-B2
Application number	US-201514966809-A
Country	US
Kind code	B2
Filing date	Dec 11, 2015
Priority date	Dec 19, 2014
Publication date	Oct 31, 2017
Grant date	Oct 31, 2017

Abstract

The problem of deck channel rewetting that occurs when a drainage chamber in a roll upwardly approaches a horizontal line extending past the horizontal diameter of the roll is solved by using a comb plate comprising at least one comb tooth engaging the perforated plate and extending through a deck channel to a drainage channel such that the at least one comb tooth has a slope configured to direct a slurry suspension from the perforated plate into the drainage channel.

First claim

What is claimed is:

1. A roll press deck channel anti-rewet assembly comprising:
a roll having support ribs arrayed across a length of the roll,
wherein adjacent support ribs define drainage channels, and wherein ends of the drainage channels are disposed at ends of the roll;
a deck disposed on tops of the support ribs,
wherein the deck comprises deck rings defining a deck channel communicating with a top of the drainage channels and a perforated plate disposed on a top of the deck rings,
wherein the perforated plate has areas defining perforations in communication with the deck channel; and
a comb plate disposed under the perforated plate, the comb plate comprising a comb tooth extending through the deck channel toward at least one of the drainage channels, the comb tooth having a first end disposed on a back of the perforated plate and a second end opposite the first end disposed in at least one of the drainage channels,
wherein the first end and the second end of the comb tooth define a slope configured to direct filtrate from the perforated plate through the deck channel and into at least one of the drainage channels.

2. The assembly of claim 1 , further comprising an anti-rewet plate disposed under the perforated plate, wherein the anti-rewet plate engages a side of at least one of the drainage channels, wherein the anti-rewet plate has a first end extending into the at least one of the drainage channels and a second end, and wherein the first end and the second end define a concave slope configured to hold a volume of filtrate in the drainage channel as the at least one of the drainage channels rotates downwardly between a center line and a nadir of the roll.

3. The assembly of claim 1 , wherein the deck further comprises multiple deck rings disposed on the tops of support ribs, wherein adjacent deck rings define deck channels between adjacent deck rings.

4. The assembly of claim 3 , wherein the comb plate further comprises multiple comb teeth extending through the deck channels communicating with the tops of the drainage channels.

5. The roll of claim 4 , wherein the comb plate further comprises a support strip and multiple comb teeth, wherein the support strip engages a side of at least one of the drainage channels and the comb teeth extend from the perforated plate, through at least one of the deck channels which is in communication with the at least one of the drainage channels, and into the support strip at intervals.

6. The assembly of claim 5 , wherein the support strip extends the length of the at least one of the drainage channels.

7. The assembly of claim 5 , wherein a comb plate is disposed in all drainage channels on a press roll.

8. The assembly of claim 5 , wherein the intervals correspond to a width of the deck rings disposed on the tops of support ribs, such that side edges of the comb teeth engage sides of the deck rings.

9. The assembly of claim 8 further comprising an anti-rewet collection plate disposed within a drainage channel with the comb plate, wherein the anti-rewet collection plate does not extend into the deck channels.

10. The assembly of claim 8 , wherein the comb plate further comprises the anti-rewet collection plate extending from an end of the support strip opposite the multiple comb teeth.

11. The assembly of claim 5 , wherein the side edges of at least one comb tooth engage sides of the deck rings.

12. The assembly of claim 1 , wherein the support ribs further comprise a deck support structure engaged to the support ribs.

13. The assembly of claim 1 , wherein the slope has a shape selected from a function selected from consisting of a logarithmic function, an exponential function, segment of a parabolic function, segment of an absolute value function, segment of a sinusoidal function, segment of a tangential function, segment of a cosinusoidal function, segment of a secant function, segment of a cosecant function, and segment of a cotangential function as graphed on a coordinate plane.

14. A method for installing a comb plate and anti-rewet plate comprising:
stopping rotational movement of a roll in a roll press, wherein the roll has support ribs arrayed across a length of the roll, wherein adjacent support ribs define drainage channels, wherein ends of the drainage channels are disposed at ends of the roll, wherein the roll further comprises a deck disposed on tops of the support ribs, the deck defines a deck channel communicating with a top of the drainage channels, and wherein a perforated plate is disposed on a top of the deck and defines an outer surface of the roll, and wherein the perforated plate defines perforations in communication with the deck channel;
removing the perforated plate exposing ends of the drainage channels;
inserting a comb plate along a length of at least one of the drainage channels, the comb plate comprising a comb tooth, wherein the comb tooth does not extend into the deck channel;
tilting the comb plate such that the comb teeth extend into the deck channel and such that comb plate will be disposed under the perforated plate after the perforated plate is reinstalled, and such that the comb plate extends through the deck channel toward the at least one of the drainage channels, the comb tooth having a first end that will be disposed on a back of the perforated plate after the perforated plate is reinstalled and a second end opposite the first end disposed in the at least one of the drainage channels, wherein the first end and the second end of the comb tooth define a slope configured to direct filtrate from the perforated plate through the deck channel into the at least one of the drainage channels;
securing the comb plate to a support rib of the at least one of the drainage channels; and reinstalling the perforated plate to define an outer surface of the roll.

15. The method of claim 14 further comprising adding an anti-rewet plate along the length of the drainage channel after the comb plate has been inserted along the length of the drainage channel, and securing the anti-rewet plate to a support rib opposite a support rib containing a comb plate.

Assignees

• Andritz Inc

Inventors

• Hallas Gregory

Classifications

• D21C9/02 Primary

  Washing {; Displacing cooking or pulp-treating liquors contained in the pulp by fluids, e.g. wash water or other pulp-treating agents} · CPC title

• D21F3/083 Primary

  perforated · CPC title

• D21C9/06

  in filters {; Washing of concentrated pulp, e.g. pulp mats, on filtering surfaces} · CPC title

• B30B9/205

  using a roller with radially arranged vanes dividing the pressing space in separate chambers · CPC title

• D21C9/18

  De-watering (de-watering in general F26B); {Elimination of cooking or pulp-treating liquors from the pulp}(D21C9/002, D21C9/02 take precedence; paper-making machines D21F; strainers in digesters D21C7/00; presses in general B30B) · CPC title