PULPING METHOD

摘要

An improved pulping method which comprises the steps of: (a) digesting a lignocellulosic material with a digesting liquid to obtain a first mixture; (b) separating the first mixture into a pulp and a digestion waste liquor; (c) treating the digestion waste liquor with a magnesiacontaining adsorbing agent to adsorb thereon at least a part of the organic components contained in the waste liquor and to obtain a second mixture; (d) separating the second mixture into a solids-rich phase including the organic components-carrying adsorbing agent and a liquid phase containing magnesium components dissolved therein; and (e) subjecting at least a portion of the organic components-carrying adsorbing agent to a calcining treatment for the removal of the organic components therefrom by combustion and for the regeneration of the adsorbing agent. The method is c h a r a c t e r i z e d i n t h a t said second mixture is added with an alkaline substance to increase its pH and to precipitate at least a part of the magnesium components dissolved therein, whereby the concentration of the magnesium components dissolved in said liquid phase is decreased.