method and system for oxygen delignification.

摘要

The invention relates to an enhanced oxygen delignification stage located between 2 wash positions (w1, w2) in a fiber line that produces targeted pulp pulp qualities. The inventive method and system divides the oxygen stage into at least 2 phases and, after the first phase, the pulp suspension is effectively depressurized and vented to the atmosphere to ventilate the bulk volume of inert gases formed during the first phase. . The partial oxygen pressure added to the last phase can thus be increased and the amount of dissolved oxygen in the liquid phase is increased, enabling better delignification of the pulp pulp in the last phase.