Wood pulp treatment

摘要

A process using a multicomponent enzyme preparation to treat screened once refined pulps and reduces the specific energy consumption and/or increasing production while maintaining or increasing handsheet physical properties. The enzyme preparation has a major endoglucanase activity, a significant mannanase activity and a relatively small cellobiohydrolase activity. This enzyme mixture is prepared from a genetically modified strain of Trichoderma reseii.

主权项

1. A method of manufacturing a wood pulp, the method comprising:
exposing a mechanical wood pulp comprising an at least once refined mechanical raw wood pulp to an enzymatic solution comprising an endoglucanase (EG), a cellbiohydrolase (CBH) and a mannanase (MAN), wherein the ratio of enzymatic activity of EG:CBH is at least 3 and the ratio of enzymatic activity of MAN:CBH is at least 1.5, and the enzymatic activity of the CBH is at least 0.05 FPU and up to 10 FPU per gm of the long-fiber fraction of the pulp based on dry weight measured according to standard T 258 om-06 for an amount of time up to about 5 hours and sufficient to reduce energy consumption during subsequent refining of the exposed pulp in which the freeness of the pulp (CSF) is reduced to below 150 ml and by at least 10% in comparison to the freeness of the same pulp which has not been exposed to the enzymatic solution while at least maintaining the tensile strength of a handsheet produced from said subsequently refined pulp in comparison with a handsheet produced from the same pulp which has not been exposed to the enzymatic solution, the tensile strength being determined according to TAPPI standard T 205 sp-06.