Process for producing dried singulated crosslinked cellulose pulp fibers

• US 7,018,508 B2
• Filed: 01/16/2002
• Issued: 03/28/2006
• Est. Priority Date: 10/30/2001
• Status: Active Grant

• Current Assignee: International Paper Company
• Original Assignee: Weyerhaeuser Company (Weyerhauser)
• Inventors: Yancey, Michael J., Vrbanac, Michael David, Wester, Brian, Dezutter, Ramon Charles
• Primary Examiner(s): FORTUNA, JOSE A
• Application Number:
  US10/051,872
• Publication Number:
  US 20030188838A1
• Time in Patent Office: 1,532 Days
• Field of Search: 162/9, 162/157.6, 162/100, 162/158, 1621811-1812, 162/182, 811/61, 812/0, 536/36, 536/56, 344/27, 343/29, 343/31, 34356-358
• US Class Current: 162/9
• CPC Class Codes: C04B 18/241 Paper, e.g. waste paper; Paper pulp
• CPC Class Codes: C04B 20/02 Treatment
• CPC Class Codes: C08J 2303/02 Starch; Degradation products thereof, e.g. dextrin
• CPC Class Codes: C08J 3/12 Powdering or granulating
• CPC Class Codes: D21C 9/001 Modification of pulp properties purification D21C9/08
• CPC Class Codes: D21C 9/002 by chemical means; preparation of dewatered pulp, e.g. in sheet or bulk form, containing special additives
• CPC Class Codes: D21C 9/007 by mechanical or physical means
• CPC Class Codes: D21C 9/18 De-watering de-watering in general F26B; Elimination of cooking or pulp-treating liquors from the pulpD21C9/002, D21C9/02 take precedence; paper-making machines D21F; strainers in digesters D21C7/00; presses in general B30B
• CPC Class Codes: D21C 9/185 comprising at least one step where the pulp is suspended in a gaseous medium, e.g. flash drying
• CPC Class Codes: D21H 11/20 Chemically or biochemically modified fibres
• CPC Class Codes: D21H 15/04 crimped, kinked, curled or twisted fibres
• CPC Class Codes: D21H 17/38 containing crosslinkable groups
• CPC Class Codes: D21H 17/63 Inorganic compounds
• CPC Class Codes: D21H 27/08 Filter paper self-supporting filtering material B01D39/14; making on paper-making machines D21F11/14
• CPC Class Codes: Y02W 30/91 Use of waste materials as fillers for mortars or concrete

Abstract

This invention provides a dried singulated crosslinked cellulose pulp fiber product as well as an apparatus and a method for forming singulated, crosslinked, and dried fibers. In accordance with the process, a feed pulp containing a crosslinker is delivered to a jet drier. The jet drier singulates and dries the feed pulp. The singulated and dried fibers are collected from the jet drier. The feed pulp may be further treated with a treatment substance. The jet drier may be maintained at negative pressure. The product fibers may have low knot count, a low fines count, as well improved kink, curl and twist. The apparatus for carrying out the process may include a pretreatment station for supplying the treatment substance, a pulp feed device designed for pulp, a pulp feed device designed for pulp and foam suspensions, and/or a fiber separation station having a vacuum conveyor.

Claims

1. A process for producing crosslinked, singulated pulp fibers comprising:

treating never-dried wet pulp received directly from a pulp mill with a crosslinker;

introducing said never-dried wet pulp directly from a pulp mill and air into a jet drier;

thereafter drying and crosslinking said pulp in said jet drier to form singulated pulp fibers; and

removing said pulp from said jet drier and separating said dried pulp fibers from said air in said jet drier, thereby producing a crosslinked singulated pulp fibers having knots, fines and accepts.

2. The process of claim 1, wherein said crosslinker is selected from the group consisting of polyacrylic acid, glyoxal, malic acid, and tartaric acid.

3. The process of claim 1, wherein said wet pulp is at least partially dewatered prior to introducing said pulp into said drier.

4. The process of claim 1, wherein said wet pulp is further treated with a treatment substance to reduce the knot content of said pulp fibers, selected from the group consisting of a surfactant and a mineral particulate.

5. The process of claim 4, wherein said treatment substance is a mineral particulate.

6. The process of claim 5, wherein the knot count of said dried pulp fibers are less than or equal to 2%, the accepts in said dried pulp fibers are greater than or equal to 77%, and the fines in said dried pulp fibers are less than or equal to 21%.

7. The process of claim 5, wherein said treatment substance is a surfactant.

8. The process of claim 4, wherein said dried pulp fibers have a knot count less than 15%.

9. The process of claim 8, wherein said dried pulp fibers have a knot count less than 10%.

10. The process of claim 8, wherein said dried pulp fibers have a knot count less than 5%.

11. The process of claim 8, wherein said dried pulp fibers have a knot count less than 2%.

12. The process of claim 7, wherein the knot count of said dried pulp fibers are less than or equal to 5%, the accepts in said dried pulp fibers are greater than or equal to 80%, and the fines in said dried pulp fibers are less than or equal to 15%.

13. The process of claim 7, wherein the knot count of said dried pulp fibers is less than or equal to 5%, the accepts in said dried pulp fibers are greater than or equal to 80%, and the fines in said dried pulp fibers are less than or equal to 13%.

14. The process of claim 7, wherein the knot count of said dried pulp fibers is less than or equal to 5%, the accepts in said dried pulp fibers are greater than or equal to 85%, and the fines in said dried pulp fibers are less than or equal to 15%.

15. The process of claim 7, wherein the knot count of said dried pulp fibers is less than or equal to 2%, the accepts in said dried pulp fibers are greater than or equal to 80%, and the fines in said dried pulp fibers are less than or equal to 15%.

16. The process of claim 1, wherein said wet pulp is further treated with a substance selected from the group consisting of a hydrophobic material, a superplasticizer, a foam, a surfactant and a water reducing agent.

17. The process of claim 1, wherein the knot count of said dried pulp fibers is less than 15%.

18. The process of claim 17, wherein the knot count of said dried pulp fibers is less than 10%.

19. The process of claim 17, wherein the knot count of said dried pulp fibers is less than 5%.

20. The process of claim 17, wherein the knot count of said dried pulp fibers is less than 2%.

21. The process of claim 1, wherein the knot count of said dried pulp fibers is less than or equal to 5%, the accepts in said dried pulp fibers are greater than or equal to 80%, and the fines in said dried pulp fibers are less than or equal to 15%.

22. The process of claim 1, wherein the knot count of said dried pulp fibers is less than or equal to 5%, the accepts in said dried pulp fibers are greater than or equal to 80%, and the fines in said dried pulp fibers are less than or equal to 13%.

23. The process of claim 1, wherein the knot count of said dried pulp fibers is less than or equal to 5%, the accepts in said dried pulp fibers are greater than or equal to 85%, and the fines in said dried pulp fibers are less than or equal to 15%.

24. The process of claim 1, wherein the knot count of said dried pulp fibers is less than or equal to 2%, the accepts in said dried pulp fibers are greater than or equal to 80%, and the fines in said dried pulp fibers are less than or equal to 15%.

25. The process of claim 1, wherein said supply pulp has a consistency of from 0.01% to 10% before introduction into said jet drier.

26. The process of claim 25, wherein said supply pulp has a consistency of from 3% to 10% before introduction into said drier.

27. The process of claim 1, wherein said singulated pulp is dried to a moisture content of 2 percent to 10 percent by weight.

28. A process for producing crosslinked, singulated pulp fibers comprising:

treating never-dried wet pulp received directly from a pulp mill with a crosslinker;

introducing air and said never-dried wet pulp directly from a pulp mill without mechanical defibering into a jet drier;

thereafter drying said pulp in said jet drier to form singulated pulp fibers; and

removing said pulp from said jet drier and separating said dried pulp fibers from said air in said jet drier, thereby producing a crosslinked singulated pulp fibers having knots, fines and accepts.