Claims
- 1. An Eop process for bleaching chemical pulp, which comprises:
providing said chemical pulp; providing an Eop aqueous bleaching solution comprising a peroxide compound, an oxygen-containing material, sodium hydroxide and magnesium hydroxide, in the absence of magnesium sulfate; and bleaching said chemical pulp with said Eop aqueous bleaching solution to form Eop bleached chemical pulp.
- 2. The process of claim 1, wherein the amount of sodium hydroxide in said Eop aqueous bleaching solution is at not more than about 8% by weight, based on the O.D. weight of said Eop chemical pulp.
- 3. The process of claim 1, wherein the ratio of sodium hydroxide to magnesium hydroxide in said Eop aqueous bleaching solution is not more than about 5:1 (based on an OH− molar ratio).
- 4. The process of claim 1, wherein the pulp viscosity of a final bleached chemical pulp is at least substantially the same as the final pulp viscosity of bleached chemical pulp which is bleached with the same total amount of an Eop aqueous bleaching solution comprising said peroxide compound, an oxygen-containing material, sodium hydroxide, with or without magnesium sulfate, in the absence of magnesium hydroxide.
- 5. The process of claim 1, wherein the final pulp brightness of said Eop bleached chemical pulp produced from the Eop bleached chemical pulp is at least substantially the same as the final pulp brightness of bleached chemical pulp which is bleached with same bleach sequence containing the same total amount of an Eop aqueous bleaching solution comprising said peroxide compound, an oxygen-containing material, sodium hydroxide, with or without magnesium sulfate, in the absence of magnesium hydroxide.
- 6. The process of claim 1, wherein the COD of bleach effluent from an Eop stage using said Eop aqueous bleaching solution is less than the COD of bleach effluent from an Eop stage which uses the same total amount of an Eop aqueous bleaching solution comprising said peroxide, an oxygen-containing material compound, sodium hydroxide, with or without magnesium sulfate, in the absence of magnesium hydroxide.
- 7. The process of claim 1, which further includes the step of providing an Ep aqueous bleaching solution comprising a peroxide compound, sodium hydroxide and magnesium hydroxide, in the absence of magnesium sulfate; and bleaching said Eop bleached chemical pulp with said Ep aqueous bleaching solution to form Ep bleached chemical pulp.
- 8. The process of claim 1, which further includes the step of providing an Ep aqueous bleaching solution consisting essentially of a peroxide compound, sodium hydroxide and magnesium hydroxide; and bleaching said Eop bleached chemical pulp with said Ep aqueous bleaching solution to form Ep bleached chemical pulp.
- 9. The process of claim 1, wherein the wet zero span tensile strength of said Eop bleached chemical pulp is at least substantially the same as the wet zero span tensile strength of bleached chemical pulp which is bleached with the same total amount of an Eop aqueous bleaching solution comprising said peroxide compound, an oxygen-containing material, sodium hydroxide, with or without magnesium sulfate, in the absence of magnesium hydroxide.
- 10. The process of claim 1, wherein the COD in the bleach effluent of said bleached Eop chemical pulp is at least about 5% less than the COD in beach effluent of said bleached chemical pulp which is bleached with the same total amount of an Eop aqueous bleaching solution comprising said peroxide compound, an oxygen-containing material, sodium hydroxide, with or without magnesium sulfate, in the absence of magnesium hydroxide.
- 11. An Eop process for bleaching chemical pulp, which comprises:
providing said chemical pulp; providing an Eop aqueous bleaching solution consisting essentially of a peroxide compound, an oxygen-containing material, sodium hydroxide and magnesium hydroxide; and bleaching said chemical pulp with said Eop aqueous bleaching solution to form said bleached chemical pulp.
- 12. The process of claim 11, wherein the amount of sodium hydroxide in said Eop aqueous bleaching solution is at not more than about 8% by weight, based on the O.D. weight of said Eop chemical pulp.
- 13. The process of claim 11, wherein the ratio of sodium hydroxide to magnesium hydroxide in said Eop aqueous bleaching solution is not more than about 5:1 (based on an OH− molar ratio).
- 14. The process of claim 11, wherein the pulp viscosity of a final bleached chemical pulp produced from the Eop bleached chemical pulp is at least substantially the same as the final pulp viscosity of bleached chemical pulp which is bleached with the same total amount of an Eop aqueous bleaching solution comprising said peroxide compound, an oxygen-containing material, sodium hydroxide, with or without magnesium sulfate, in the absence of magnesium hydroxide.
- 15. The process of claim 11, wherein the final pulp brightness of said Eop bleached chemical pulp is at least substantially the same as the final pulp brightness of bleached chemical pulp which is bleached with same bleach sequence containing the same total amount of an Eop aqueous bleaching solution comprising said peroxide compound, an oxygen-containing material, sodium hydroxide, with or without magnesium sulfate, in the absence of magnesium hydroxide.
- 16. The process of claim 11, wherein the COD of bleach effluent from an Eop stage using said Eop aqueous bleaching solution is less than the COD of bleach effluent from an Eop stage which uses the same total amount of an Eop aqueous bleaching solution comprising said peroxide, an oxygen-containing material compound, sodium hydroxide, with or without magnesium sulfate, in the absence of magnesium hydroxide.
- 17. The process of claim 11, which further includes the step of providing an Ep aqueous bleaching solution comprising a peroxide compound, sodium hydroxide and magnesium hydroxide, in the absence of magnesium sulfate; and bleaching said Eop bleached chemical pulp with said Ep aqueous bleaching solution to form Ep bleached chemical pulp.
- 18. The process of claim 11, which further includes the step of providing an Ep aqueous bleaching solution consisting essentially of a peroxide compound, sodium hydroxide and magnesium hydroxide; and bleaching said Eop bleached chemical pulp with said Ep aqueous bleaching solution to form Ep bleached chemical pulp.
- 19. The process of claim 11, wherein the wet zero span tensile strength of said Eop bleached chemical pulp is at least substantially the same as the wet zero span tensile strength of bleached chemical pulp which is bleached with the same total amount of an Eop aqueous bleaching solution comprising said peroxide compound, an oxygen-containing material, sodium hydroxide, with or without magnesium sulfate, in the absence of magnesium hydroxide.
- 20. The process of claim 11, wherein the COD in the bleach effluent of said bleached Eop chemical pulp is at least about 5% less than the COD in beach effluent of said bleached chemical pulp which is bleached with the same total amount of an Eop aqueous bleaching solution comprising said peroxide compound, g v; an oxygen-containing material, sodium hydroxide, with or without magnesium sulfate, in the absence of magnesium hydroxide.
- 21. An Eop aqueous chemical solution for bleaching chemical pulp, which comprises an Eop aqueous bleaching solution consisting essentially of a peroxide compound, an oxygen-containing material, sodium hydroxide and magnesium hydroxide.
- 22. The Eop aqueous bleaching solution of claim 21, wherein the amount of sodium hydroxide in said Eop aqueous bleaching solution is at not more than about 8% by weight, based on the O.D. weight of said chemical pulp.
- 23. The Eop aqueous bleaching solution of claim 21, wherein the ratio of sodium hydroxide to magnesium hydroxide in said Eop aqueous bleaching solution is not more than about 5:1 (based on an OH− molar ratio).
- 24. The Eop aqueous bleaching solution of claim 21, wherein the pulp viscosity of the final chemical pulp produced using said Eop aqueous bleaching solution is at least substantially the same as the pulp viscosity of final bleached chemical pulp which is bleached with the same total amount of an Eop aqueous bleaching solution comprising said peroxide, an oxygen-containing material compound, sodium hydroxide, with or without magnesium sulfate, in the absence of magnesium hydroxide.
- 25. The Eop aqueous bleaching solution of claim 21, wherein the pulp brightness of Eop bleached chemical pulp produced using said Eop aqueous bleaching solution is at least substantially the same as the pulp final brightness of bleached chemical pulp which is bleached with a bleaching sequence containing the same total amount of an Eop aqueous bleaching solution comprising said peroxide, an oxygen containing compound, sodium hydroxide, with or without magnesium sulfate, in the absence of magnesium hydroxide.
- 26. The Eop aqueous bleaching solution of claim 21, wherein the COD of bleach effluent produced using said Eop aqueous bleaching solution is less than the COD of bleach effluent which is produced by the same total amount of an Eop aqueous bleaching solution comprising said peroxide compound, an oxygen-containing material, sodium hydroxide, with or without magnesium sulfate, in the absence of magnesium hydroxide.
- 27. The Eop aqueous bleaching solution of claim 21, wherein the ratio of sodium hydroxide to magnesium hydroxide in said Eop aqueous bleaching solution is not more than about 3:1 (based on an OH− molar ratio).
- 28. The Eop aqueous bleaching solution of claim 21, wherein the ratio of sodium hydroxide to magnesium hydroxide in said Eop aqueous bleaching solution is not more than about 1:2 (based on an OH− molar ratio).
- 29. The Eop aqueous bleaching solution of claim 21, wherein the wet zero span tensile strength of Eop bleached chemical pulp produced using said Eop aqueous bleaching solution is at least substantially the same as the wet zero span tensile strength of bleached chemical pulp which is bleached with the same total amount of an Eop aqueous bleaching solution comprising said peroxide compound, an oxygen-containing material, sodium hydroxide, with or without magnesium sulfate, in the absence of magnesium hydroxide.
- 30. The Eop aqueous bleaching solution of claim 21, wherein COD in the bleach effluent of said bleached Eop chemical pulp is at least about 5% less than the COD in the bleach effluent of said bleached chemical pulp which is bleached with the same total amount of an Eop aqueous bleaching solution comprising said peroxide compound, an oxygen-containing material, sodium hydroxide, with or without magnesium sulfate, in the absence of magnesium hydroxide.
- 31. An Ep process for bleaching chemical pulp, which comprises:
providing said chemical pulp; providing an Ep aqueous bleaching solution comprising a peroxide compound, sodium hydroxide and magnesium hydroxide, in the absence of magnesium sulfate; and bleaching said chemical pulp with said Ep aqueous bleaching solution to form said bleached chemical pulp.
- 32. An Ep process for bleaching chemical pulp, which comprises:
providing said chemical pulp; providing an Ep aqueous bleaching solution consisting essentially of a peroxide compound, sodium hydroxide and magnesium hydroxide; and bleaching said chemical pulp with said Ep aqueous bleaching solution to form said bleached chemical pulp.
- 33. An Ep aqueous chemical solution for bleaching chemical pulp, which comprises an Ep aqueous bleaching solution consisting essentially of a peroxide compound, sodium hydroxide and magnesium hydroxide.
- 34. A process for bleaching chemical pulp, which comprises:
providing said chemical pulp; providing an Eop aqueous bleaching solution; bleaching said chemical pulp with said Eop aqueous bleaching solution to form Eop bleached chemical pulp; providing an Ep aqueous bleaching solution comprising a peroxide compound, sodium hydroxide and magnesium hydroxide, in the absence of magnesium sulfate; and bleaching said Eop bleached chemical pulp with said Ep aqueous bleaching solution to form Ep bleached chemical pulp.
- 35. A process for bleaching chemical pulp, which comprises:
providing said chemical pulp; providing an Eop aqueous bleaching solution; bleaching said chemical pulp with said Eop aqueous bleaching solution to form Eop bleached chemical pulp; providing an Ep aqueous bleaching solution consisting essentially of a peroxide compound, sodium hydroxide and magnesium hydroxide; and bleaching said Eop bleached chemical pulp with said Ep aqueous bleaching solution to form Ep bleached chemical pulp.
RELATED APPLICATION
[0001] This application claims priority from Provisional Application Serial No. 60/271,987 filed on Feb. 27, 2001.
Provisional Applications (1)
|
Number |
Date |
Country |
|
60271987 |
Feb 2001 |
US |