METHOD OF REDUCING THE SILICON CONTENT OF GREEN LIQUOR

摘要

The present invention relates to a method of reducing the silicon content of green liquor in a pulp mill by means of a compound containing a divalent or trivalent cation, in which method waste liquor containing cooking chemicals of an alkaline pulping process and silicon is concentrated in order to increase the dry solids content of the liquor, and the concentrated waste liquor is combusted in order to produce smelt and the smelt is dissolved in order to form green liquor. An essential characteristic of the invention is that a compound containing a divalent or trivalent cation is added into waste liquor so that the cation-containing compound reacts in the smelt with silicon in order to form a compound containing a cation and silicon, which compound is separated from the green liquor.