FORFARANDE FOR FRAMSTELLNING AV DISSOLVINGMASSA OCH/ELLER PAPPERSMASSA AV LIGNOCELLULOSAMATERIAL JEMTE ANLEGGNIG FOR GENOMFORANDE AV DETTA FORFARANDE

摘要

In a process for producing dissolving and/or papermaking pulp from lignocellulose material, the lignocellulose material is digested in at least two stages with an alkali-containing solution and an oxygen-containing gas. The digestion waste liquor is then further processed. To be able to save oxygen, more than 30% by weight of the lignocellulose material, based on its dry weight, is made to dissolve in the first stage. It is only in the second digestion stage that an oxygen-containing gas is added to the digestion solution.