METHOD FOR PRODUCTION OF MECHANICAL WOOD PULP SUITABLE FOR MANUFACTURING OF PAPER OR CARDBOARD Russian patent published in 2010 - IPC D21B1/16 D21C9/16 

FIELD: textile, paper.

SUBSTANCE: method relates to production of mechanical or chemical-mechanical wood pulp applied as raw material for manufacturing of paper or cardboard, and may be used and pulp and paper industry. According to this method wood pulp is exposed to fibrillation. Produced wood pulp is screened to separate wastes from acceptable materials. At the same time wastes are removed in amount of maximum 60% of overall amount of wood pulp. Wastes and acceptable material are bleached separately. Wastes are bleached with the help of peroxide or peroxy acid. After that bleached wastes are mixed with bleached acceptable material. After combination they are exposed to finishing grinding, at the same time amount of consumed energy makes approximately 10-1000 kW-hr/ton. Finishing grinding is carried out at low concentration. Then wood pulp is batched into paper- or cardboard-making machine. Wastes are bleached in alkaline medium.

EFFECT: improved strength of wood pulp and reduction of energy consumed for grinding.

12 cl, 1 dwg, 1 ex