Förfarande och anordning vid kontinuerlig kokning av kemisk cellulosamassa : Method and device for the continuous cooking of pulp

• The invention concerns an arrangement and a method for the continuous cooking of chemical cellulose pulp in a continuous digester system (100). The continuous digester system (100) comprises an inlet (102) for the feed of a chips suspension and an outlet (103) for the output of a cooked suspension of pulp. The suspension of chips is fed in to the inlet through a line (105) at the beginning of the cook, where the chips suspension has a volume of starting cooking fluid that establishes a fluid/wood ratio that is greater than 3.5. The invention is characterised in that a final cooking fluid is present during the cook for the major part of the cook and is withdrawn through a withdrawal strainer (106) only during the final 15 minutes of the cook. The final cooking fluid ensures a fluid/wood ratio that is greater than 3.5 in association with the withdrawal. The withdrawn final cooking fluid during the final 15 minutes of the cook consists of spent black liquor, which maintains a residual alkali level that lies under 15 g/l.

Ämnesord

NATURVETENSKAP  -- Kemi (hsv//swe)

NATURAL SCIENCES  -- Chemical Sciences (hsv//eng)

Publikations- och innehållstyp

pop (ämneskategori)

pat (ämneskategori)