EP0351655A1
Expired / Lapsed
EP
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A method for the treatment of pulp
Assignee: Genencor International Europe Oy
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Filing: 1989-07-06
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Granted: —
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Expires: 2009-07-06
Abstract
Abstract The invention relates to a method for improving the drainability of mechanical pulp or pulp mainly containing mechanical pulp by means of enzyme treatment by adding to the pulp at least one hemicellulose-dissolving enzyme or an enzyme preparation containing at least one hemicellulose-dissolving enzyme and being substantially free from cellulose-dissolving enzymes. The enzyme treatment according to the invention not only improve the drainability of the pulp but also retains the strength properties of the pulp since no cellulose-dissolving enzymes are used.
Inventors
- 👤 Sakari Karsila
- 👤 Ilkka Kruus
- 👤 Outi Puuppo
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 07:04
CPC Classifications
D; D21; D21C; D21C5/00; D21C5/005
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
49 words
A method for improving the drainability of mechanical pulp or pulp mainly containing mechanical pulp by means of enzyme treatment, character ized by adding to the pulp at least one hemicellulose-dissolving enzyme or an enzyme preparation containing at least one hemicellulose-dissolving enzyme and being substantially free from cellulose-dissolving enzymes.
Claim 2
Independent Claim
49 words
A method for improving the drainability of mechanical pulp or pulp mainly containing mechanical pulp by means of enzyme treatment, character ized by adding to the pulp at least one hemicellulose-dissolving enzyme or an enzyme preparation containing at least one hemicellulose-dissolving enzyme and being substantially free from cellulose-dissolving enzymes.
Claim 3
Dependent Claim
15 words
A method according to claim 1, characterized in that the mechanical pulp is thermomechanical pulp.
Claim 4
Dependent Claim
15 words
A method according to claim 1, characterized in that the mechanical pulp is deinked pulp.
Claim 5
Dependent Claim
30 words
A method according to claim 1 or 3, characterized in that the addition of the enzyme /enzymes is carried out in connection with or after the acidification of the pulp.
Claim 6
Independent Claim
39 words
A method according to any of the preceding claims, characterized in that the hemicellulose-dissolving enzyme or enzyme preparation is added in an amount of about 30 to about 200,000 enzyme units/kg calculated on the dry substance of the pulp.
Claim 7
Dependent Claim
36 words
A method according to claim 5, characterized in that the hemicellulose-dissolving enzyme or enzyme preparation is added in an amount of about 100 to about 50,000 enzyme units/kg calculated on the dry substance of the pulp.
Claim 8
Independent Claim
26 words
A method according to any of the preceding claims, characterized in that xylanase or xylanase preparation substantially free from cellulose-dissolving enzymes is added to the pulp.
Claim 9
Independent Claim
26 words
A method according to any of the preceding claims, characterized in that mannanase or mannanase preparation substantially free from cellulose-dissolving enzymes is added to the pulp.
Claim 10
Independent Claim
28 words
A method according to any of the preceding claims, characterized in that the enzyme treatment is carried out within the pH range from about 2 to about 10.
Claim 11
Dependent Claim
25 words
A method according to claim 9, characterized in that the enzyme treatment is carried out within the pH range from about 4 to about 8.
Claim 12
Independent Claim
25 words
A method according to any of the preceding claims, characterized in that the enzyme treatment is carried out at about 10 to 90 o C.
Claim 13
Dependent Claim
22 words
A method according to claim 11, characterized in that the enzyme treatment is carried out at about 25 to 70 o C.
References Cited (Backward Citations)
FR2557894A1
Cited
FR2604198A1
Cited
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