| 摘要 |
<p>In the prodn. of paper pulp from wood, straw or old papers, the pulp is submitted to high vacuum, in one or more stages, with pressuring interspersed between them, previous to the known preparation of the pulp using a mechanical tearing process. A liquid impregnation of the pulp is effected during the high vacuum stage. The introduction of high vacuum stages reduces the energy requirement for pulping, provides a more efficient re-cycling of basic materials, and improves the impregnation of saturation liquors. There is a reduced risk of long fibre shrinkage or breakage.</p> |
