Extraction of Spent Pulping Liquors and Bleaching Effluents

2 Extraction of Spent Pulping Liquors and Bleaching Effluents 

Note 1. The volume of black liquor should be a maximum of 80% of the volume of extractor tube so that it does not overflow into the solvent flask. 

Note 2. Some technical lignins will precipitate at this pH. It is important to prevent their deposition on the fritted disc at the base of the inner tube to insure that extraction will not cease. 

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