CHEMIMECHANICAL PULPING PROCESS EMPLOYING SODIUM CARBONATE AND SODIUM SULPHITE

摘要

The present invention relates to a high yield chemimechanical pulping process for producing pulp from wood chips or sawdust or other lignocellulosic materials which comprises treating said lignocellulosic material with an aqueoussolution of mixture of sodium sulphite and sodium carbonate or sodium bisulphiteand sodium carbonate, sulphonating the treated material in a liquid phase or vapour phase cooking, and subsequently subjecting the resulting sulphonated material tomechanical defibration.