Method and apparatus for the continuous digestion of cellulosic materials
Abstract
Abstract CELLULOSIC MATERIALA ARE CONTINUOUSLY DIGESTED AND SUBSEQUENTLY WASHED WITH A LIQUID TO PRODUCE A PULP IN A CLOSED, SUBSTANTIALLY STRAIGHT VESSEL HAVING AT LEAST ONE PARTITION STRUCTURE WITHIN IT AND EXTENDING GENERALLY TRANSVERSELY AND SUBSTANTIALLY LONGITUDINALLY OF THE VESSEL TO DIVIDE IT INTO AT LEAST TWO GENERALLY LONGITUDINALLY EXTENDING COMPARTMENTS. STEAM IS INTRODUCED INTO THE UPPER PART OF THE VESSEL FOR DIGESTION OF THE MATERIAL, AND A WASHING LIQUID IS INTRODUCED SEPARATLEY UNDER CONTROLLED CONDITIONS INTO THE RESPECTIVE COMPARTMENTS TO WASH THE MATERIAL. CELLULOSIC MATERIALS WHICH HAVE BEEN PRETREATED WITH CHEMICALS THAT PROMOTE DIGESTION ARE INTRODUCED SEPARATELY INTO EACH COMPARTMENT AND ARE WITHDRAWN SEPARATELY FROM EACH COMPARTMENT AT CONTROLLED RATES.
Inventors
- 👤 G Ingemarsson
Bibliographic Details
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