|
(11) | EP 1 932 967 A3 |
(12) | EUROPEAN PATENT APPLICATION |
|
|
|
|
|||||||||||||||||||
(54) | A method for producing cellulose pulp in a continuous digester in an energy-efficient manner |
(57) The invention describes a method for producing cellulose pulp in a continuous digestion
system in an energy-efficient manner. Cellulose chips are fed continuously with a
transfer liquid in a transfer line (11) to a top separator (20) arranged at the top
of a digester (30), for the separation of free liquid from the cellulose chips. The
top separator has a withdrawal space (21) in which free liquid collects. At least
a fraction of the free liquid that has separated, with a temperature Tut, is led in a return line (32) from the withdrawal space of the top separator to a
position to be used as transfer liquid. At least one pressurised withdrawal of black
liquor is carried out in the digester (30) essentially at the cooking temperature
of at least 135 °C. The invention is characterised in that an additive liquid with
a temperature Tin is added at the withdrawal space (21) of the top separator, where Tin>Tut.
|