Paper pulp prodn. using peroxide delignification - with mechanical pretreatment to improve water absorption of wood pieces

摘要

The process for prepn. of paper-making pulp or analogous mechanical/chemical processes by delignification of lignocellulosic materials by means of hydrogen peroxide or a sodium peroxide in alkaline medium comprises treating the fragments of lignocellulosic material before cooking to a mechanical pretreatment having a combined compressing and shearing effect to loosen the bonds between the fibres but leaving the fragments substantially in their organised structure. The process enables a uniform quality pulp by assisting penetration of the agent into the fibre. The cooking time is satisfactory and the yield is equal to normal pulp processes without any damage to the fibres.