The digester and method are for the continuous cooking of pulp. At least
two withdrawal positions (11E, 11D) for cooking fluid are arranged at
different heights in the digester (10). The cooking fluid in the first
and second position is withdrawn after the chips have had a retention
time that differs by at least 10 minutes. The differential pressure
between the positions is determined and when this exceeds a
pre-determined level, a connection (17E) opens between these positions,
establishing a flow parallel to a flow of cooking fluid between these
positions in the digester. Several withdrawal positions are preferably
connected in a common shunt system (17A-17F), with valves (18A-18F),
controlled by the differential pressure, that are located between
adjacent positions.