FIELD: paper industry.
SUBSTANCE: method includes treatment of wood chips by acid solution in process of extraction by steam, liquid containing water or their combination to remove hemicellulose. In one version prior to treatment or in process of treatment peroxide is used, and sulfate boiling is carried out until hemicelluloses content in modified sulfate cellulose becomes from more than 5 to approximately 9%. In another version after extraction of wood chips chemical or semi-chemical boiling is carried out until content of hemicelluloses becomes from 3 to 15% with further washing and bleaching. In the third version after chemical and semi-chemical boiling until content of hemicelluloses becomes approximately from 3 to 15%, bleaching is carried out.
EFFECT: improved brightness and volume with better dehydration of cellulose, fineness of grinding and efficiency.
11 cl, 3 dwg, 5 tbl, 4 ex
