| 摘要 |
The invention concerns a method for treatment of pulp in connection with bleaching. The pulp is first cooked and acid-delignified if necessary to lower its kappa number to below 24, preferably below 14, after which it is treated in an acid stage at a pH of 2-5 in the temperature range of 75-130 degrees Celsius to lower its kappa number by 2-9 units. In order to prevent significant reduction in the strength value of the pulp, the dwell time in the treatment tower of the acid stage is 30-300 minutes and the treatment temperature T degrees Celsius is T subscripts min < T < T subscripts max. The invention also pertains to an apparatus system intended to be employed in the method. <IMAGE>
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