A method for the production of chemical mechanical fiber materials by heating and separation of with sulfite solutions impregnated wood hack do in thick dampfatmosphaere under pressure and at an elevated temperature

摘要

Chemo-mechanical pulp is produced in high yield by impregnating chips, e.g. of pine, at a temperature below 100 DEG C, with a dilute solution of alkali hydroxide or carbonate, and then, in the absence of free impregnating solution, feeding them into a pressure vessel containing saturated steam at elevated pressure and at least enough free SO2 to transform the base to sulphite or bisulphite. There may be an excess of SO2. They are cooked in this vessel for a short time, and then defibred while still at elevated temperature and pressure.