METHOD OF PREPARING BLEACHED CHEMICO-THERMOMECHANICAL WOOD PULP FROM BROAD-LEAVED WOOD

摘要

FIELD: paper-and-pulp industry.;SUBSTANCE: wood pulp is steamed at 105-120^оС, treated with hydrogen peroxide, sodium peroxide, and complexing agent. Simultaneously, first step of grinding is carried out followed by second-step grinding and bleaching. Bleached pulp is subjected to further grinding at pulp concentration 2-5% and degree of grinding exceeding degree of the second-step grinding by a specified value. Treatment of steamed wood may be performed in presence of sodium silicate. Broad-leaved wood is selected from birch, aspen wood, and mixture thereof.;EFFECT: increased yield of desired product and increased its mechanical strength.;4 cl, 1 tbl, 7 ex