Delignification and bleaching of a cellulose pulp slurry with oxygen
Abstract
Abstract COLLULOSE PULP IS CONTINUOUSLY BLEACHED AND DELIGNIFIED BY OXYGEN, WITHOUT REQUIRING THE USE OF A CELLULOSE DEPOLYMERIZATION PROTECTIVE AGENT, WHEREBY AN ALKALINE AQUEOUS PULP SLURRY OF A CONSISTENCY OF FROM ABOUT 2 TO 10%, HAVING A PH OF BETWEEN ABOUT 9 AND 14, A REACTION TEMPERATURE OF BETWEEN ABOUT 70* AND 120*C, WITH THE OXYGEN DISSOLVED AND INTIMATELY DISPERSED AND SUBDIVIDED INTO THE SLURRY SO THAT NO AGGLOMERATED BUBBLES ARE FORMED AND THE OXYGENATED PULP SLURRY HAS SUBSTANTIALLY NO BUBBLES EXCEEDING ABOUT 1/16 INCH IN DIAMETER, AND THEREAFTER CONTINUOUSLY INTRODUCING THE SLURRY INTO THE LOWER REGION OF A VERTICAL ELONGATED TOWER AND FLOWING THE SLURRY UPWARDLY THROUGH THE TOWER WITHOUT ANY SUBSTANTIAL AGITATION, SO AS TO GRADUALY DECREASE THE PRESSURE TO WHICH THE SLURRY IS OBJECTED AND CONTINUOUSLY WITHDRAWING TREATED SLURRY FROM THE UPPER REGION OF SAID TOWER.
Inventors
- 👤 S Roymoulik
- 👤 K Brown
Bibliographic Details
Claims Analysis
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