Refiner for refining lignocellulosic material and refining segments for such a refiner

Patent metadata

Field	Value
Publication number	US-11701665-B2
Application number	US-202017021075-A
Country	US
Kind code	B2
Filing date	Sep 15, 2020
Priority date	Nov 18, 2019
Publication date	Jul 18, 2023
Grant date	Jul 18, 2023

Abstract

A refiner for refining of lignocellulosic material includes a rotor disc and a stator disc. The rotor disc includes a first refining segment that includes a plurality of first protruding structures for grinding of the lignocellulosic material. Each of the first protruding structures is defined by a first height. The stator disc is arranged opposite the rotor disc and includes a second refining segment that includes a plurality of second protruding structures for grinding of the lignocellulosic material. Each of the second protruding structures being defined by a second height. The first height is at least three times larger than the second height.

First claim

The invention claimed is:

1. A refiner for refining of lignocellulosic material, the refiner comprising:
a rotor disc comprising a first refining segment that includes a plurality of first protruding structures for grinding of the lignocellulosic material, each of the first protruding structures being defined by a first height; and
a stator disc arranged opposite the rotor disc, the stator disc comprising a second refining segment that includes a plurality of second protruding structures for grinding of the lignocellulosic material, each of the second protruding structures being defined by a second height;
wherein the first height is at least three times larger than the second height; and
wherein the first protruding structures are separated from the second protruding structures by a disc gap;
wherein the refiner is configured to facilitate refining of the lignocellulosic material in the disc gap;
wherein the first refining segment is made from a first material; and
wherein the second refining segment is made from a second material, the second material being harder than the first material.

2. The refiner of claim 1 , wherein the first protruding structures comprise a plurality of first bars extending radially from an inner periphery of the first refining segment to an outer periphery of the first refining segment.

3. The refiner of claim 2 , wherein each of the first bars is separated from another of the first bars by a distance that is between 0.1 centimeters (cm) and 1 cm.

4. The refiner of claim 2 , wherein:
the second protruding structures comprise a plurality of second bars extending radially from an inner periphery of the second refining segment to an outer periphery of the second refining segment;
each of the second bars has a width of 0.5 millimeters (mm) to 2.5 mm; and
each of the first bars has a width of 1 mm to 5 mm.

5. The refiner of claim 4 , wherein each of the first bars is separated from another of the first bars by a distance that is between 0.1 centimeters (cm) and 1 cm.

6. The refiner of claim 1 , wherein at least some of the second protruding structures are pyramids or stubs.

7. The refiner of claim 1 , wherein the first protruding structures comprise a plurality of first bars extending radially from an inner periphery of the first refining segment to an outer periphery of the first refining segment.

8. A refiner segment pair comprising:
a first segment configured to be used with a rotor disc for a refiner of a lignocellulosic material, the first segment comprising a plurality of first protruding structures for grinding of the lignocellulosic material, each of the first protruding structures defined by a first height; and
a second segment configured to be used with a stator disc for the refiner of lignocellulosic material, the second segment comprising a plurality of second protruding structures for grinding of the lignocellulosic material, each of the second protruding structures being defined by a second height;
wherein the first height is at least three times larger than the second height;
where the first refining segment is made from a first material; and
wherein the second refining segment is made from a second material, the second material being harder than the first material.

9. The refiner segment pair of claim 8 , wherein the first protruding structures comprise a plurality of first bars extending radially from an inner periphery of the first segment to an outer periphery of the first segment.

10. The refiner segment pair of claim 9 , wherein:
the second protruding structures comprise a plurality of second bars extending radially from an inner periphery of the second segment to an outer periphery of the second segment;
each of the second bars has a width of 0.5 millimeters (mm) to 2.5 mm; and
each of the first bars has a width of 1 mm to 5 mm.

11. The refiner segment pair of claim 10 , wherein each of the first bars is separated from another of the first bars by a distance that is between 0.1 centimeters (cm) and 1 cm.

12. The refiner segment pair of claim 9 , wherein each of the first bars is separated from another of the first bars by a distance that is between 0.1 centimeters (cm) and 1 cm.

13. The refiner segment pair of claim 8 , wherein at least some of the second protruding structures are pyramids or stubs.

14. The refiner segment pair of claim 8 , wherein the first protruding structures comprise a plurality of first bars extending radially from an inner periphery of the first segment to an outer periphery of the first segment.

15. A refiner for refining of lignocellulosic material, the refiner comprising:
a rotor disc comprising a first refining segment that includes a plurality of first protruding structures for grinding of the lignocellulosic material, each of the first protruding structures being defined by a first height being uniform from an inner radial surface of a corresponding one of the first protruding structures to an outer radial surface of the corresponding one of the first protruding structures; and
a stator disc arranged opposite the rotor disc, the stator disc comprising a second refining segment that includes a plurality of second protruding structures for grinding of the lignocellulosic material, each of the second protruding structures being defined by a second height being uniform from an inner radial surface of a corresponding one of the second protruding structures to an outer radial surface of the corresponding one of the second protruding structures;
wherein the first height is at least three times larger than the second height; and
wherein the first protruding structures are separated from the second protruding structures by a disc gap;
wherein the refiner is configured to facilitate refining of the lignocellulosic material in the disc gap;
wherein the first refining segment is made from a first material; and
wherein the second refining segment is made from a second material, the second material being harder than the first material.

Assignees

• Valmet Oy

Inventors

• Hedlund Christer
• Lönngren Karl
• Lundfors Mikael

Classifications

• B02C7/12 Primary

  Shape or construction of discs · CPC title

• B02C7/06 Primary

  with horizontal axis (B02C7/04 takes precedence) · CPC title

• B02C7/188

  Driving mechanisms · CPC title

• D21D1/30

  Disc mills · CPC title

• D21D1/303 Primary

  Double disc mills · CPC title