| 摘要 |
A process for manufacturing bleached groundwood pulp of improved and uniform quality, in which debarked wood logs or wood chips are ground in a closed pocket grinder at atmospheric or super-atmospheric pressure, while applying shower water to the free surfaces of the grindstone, and shower water containing bleaching chemicals to the grinding zone where the wood is in contact with the grindstone, i.e., such as by spraying such shower water upon the end portions of the logs or chip mass, optionally combined with a supply of shower water delivered via the ram plates and a water trap arranged around the lower part of the log pockets facing the grindstone, so as to maintain a high uniform level of moisture content in the grinding zone, and to retain the shower water within said zone to an extent such that hollows between the logs or chips located nearest the surface of the stone are also filled with shower water; the wood can thus be brought into effective contact with bleaching chemicals at an early stage, resulting in a pulp of high brightness. |
