PROCESS FOR PRODUCING CHEMOMECHANICAL AND/OR CHEMOTHERMOMECHANICAL WOOD PRODUCTS

摘要

A process is disclosed for producing chemomechanical and/or chemothermomechanical wood products from lignocellulosic raw materials, such as wood chips. The raw materials are impregnated with a SO2-containing solution and then subjected to a sulfonating reaction in a gaseous or vapour phase at a pH value equal to 2 or less. When the sulfonating reaction is finished, the raw materials or wood chips are defibrated in a defibrating unit known per se and are crushed down to a preselected fineness degree. The wood product thus obtained is characterized by remarkable solidity and by requiring a reduced specific crushing energy.