| 摘要 |
The present invention relates to a method of bleaching pulp to a brightness of at least ISO 80 by utilizing at least two of the following bleaching agents: oxygen, ozone, peroxide. The invention is characterized of cooking the pulp, treating the pulp with at least one of the following agents or manners: acidifying, EDTA and DTPA, for removing heavy metals, delignifying pulp in a pressurized, two-step oxygen stage, and bleaching the pulp with at least one of the following agents: O2, O3, ClO2, H2O2.
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