| 摘要 |
The invention concerns a process for the production of peracetic acid (CH<SUB>3</SUB>COOOH) for use in association with the bleaching or delignification of cellulose pulp and a method for the bleaching or delignification of cellulose pulp in which at least one treatment stage is used in which peracetic acid is batchwise added as the principal bleaching agent. The peracetic acid is formed according to the invention from a reaction between hydrogen peroxide H<SUB>2</SUB>O<SUB>2</SUB> and cellulose acetate AC in alkali conditions in the cellulose pulp. The complete reaction mixture is subsequently acidified and allowed to react with the cellulose pulp in a Paa stage. A reduced COD load is achieved through the invention, and equally good or better delignification and bleaching results are achieved as those achieved with the use of peracetic acid produced by another method. Residual products from the production process allow also the possibilities for modification of the properties of the fibres, through increased pulp strength, and increased yield. |
