Process for producing pulp with a mixture of formic acid and acetic acid as cooking chemical
First Claim
Patent Images
1. A formic acid based cooking process for producing pulp from herbaceous plants and deciduous trees by adjusting the hemicellulose content of pulp, said method comprising:
- cooking said pulp in a cooking acid composition at a cooking temperature ranging from 110 to 140°
C. for a cooking time ranging from 20 to 80 minutes, wherein said cooking acid composition includes formic acid in an amount ranging from 40 to 80% and acetic acid in an amount ranging from 10 to 30%.
1 Assignment
0 Petitions
Accused Products
Abstract
A process based on formic acid cooking for producing pulp from herbaceous plants and deciduous trees by using acetic acid as an additional cooking chemical. The obtained pulp can be used in fine paper and board production as short-fibered material, for instance. The invention also relates to a process for adjusting the hemicellulose content of the pulp in connection with the formic acid cooking by using acetic acid as an additional cooking chemical.
15 Citations
10 Claims
-
1. A formic acid based cooking process for producing pulp from herbaceous plants and deciduous trees by adjusting the hemicellulose content of pulp, said method comprising:
-
cooking said pulp in a cooking acid composition at a cooking temperature ranging from 110 to 140°
C. for a cooking time ranging from 20 to 80 minutes,wherein said cooking acid composition includes formic acid in an amount ranging from 40 to 80% and acetic acid in an amount ranging from 10 to 30%. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
wherein said cooking acid composition includes acetic acid in an amount ranging from 10 to 15%. -
8. A formic acid based cooking process according to claim 1 for producing pulp from herbaceous plants and deciduous trees by adjusting the hemicellulose content of pulp
wherein said pulp is cooked at a cooking pressure ranging from 1.5 to 3 bar. -
9. A formic acid based cooking process according to claim 1 for producing pulp from herbaceous plants and deciduous trees by adjusting the hemicellulose content of pulp
wherein regenerated mixed acid containing formic acid and acetic acid included into the spent cooking liquor obtained from the cooking is used as said cooking acid composition. -
10. The process according to claim 1, wherein the acetic acid ranges from 10 to 15%.
-
Specification