Producing fibrous material from lignocellulosic material comprises preparing a chemical solution with less percentage of sulfite, mixing the solution with wood, heating, removing the solution, pulping and separating the woods and solution

摘要

Producing fibrous material from lignocellulosic raw material comprises: producing a chemical solution with less than 25% of sulfite (calculated as sodium bisulfite) related to the oven-dried lignocellulosic raw material; mixing the chemical solution with wood in a given liquor ratio; heating the chemical solution and the wood at a temperature above the room temperature and subsequently either removing free-flowing chemical solution and pulping the wood in the vapor phase or pulping the wood in liquid phase and separating the free-flowing chemical solution and the wood.