METHOD FOR REDUCING DIGESTION WHITE LIQUOR IN CONTINUOUS DIGESTER

摘要

PROBLEM TO BE SOLVED: To provide a method for reducing a digestion white liquor in a continuous digester, comprising using the tower-like vessel type continuous digester to produce pulp, which enables the prevention of chip hanging and the reduction in the amount of a used cooking chemical liquor (white liquor). SOLUTION: This method for reducing the digestion white liquor in the lower-like vessel type continuous digester is characterized by disposing an upper circulation line L6for returning a part of the cooking chemical liquor from an upper circulation strainer 2 disposed in a boundary between a penetration zone A and a digestion zone B to the top portion of the vessel V, extracting a partial chemical liquor Z6from the circulation liquor of the upper circulation line L6, and feeding a part or all Z60of the extracted chemical liquor Z6into the top circulation feed line L0and/or the upper circulation line L6. In addition to the upper circulation line L6, a middle circulation line L7for circulating a part of the cooling chemical liquor from a middle circulation strainer 3 disposed below the upper circulation strainer 2 to the top portion of the vessel V can also be disposed to feed a part or all Z60of the extracted chemical liquor Z6from the circulated liquor of the upper circulation line L6to the middle circulation line L7. COPYRIGHT: (C)2005,JPO&NCIPI