METHOD OF PRODUCING CELLULOSE PULP Russian patent published in 2017 - IPC D21C3/00 

FIELD: technological processes.

SUBSTANCE: method of defibring lignocellulose-bearing raw material with a polysulphide-bearing cooking liquor in a boiler for continuous cooking. According to this invention, the cooking liquor is mixed into the raw material which is to be defibred before the cooking, and the cooking liquor is allowed to absorb into the raw material at a temperature which is at maximum approximately 130 °C. After that, cooking liquor used in the absorption is separated from the treated raw material, separated cooking liquor is heated to a temperature of approximately 140–170 °C, after which, the generated hot cooking liquor is mixed back into the treated raw material, possibly together with a fresh feed of cooking liquor, and raw material is defibred with a hot cooking liquor in the boiler for continuous cooking in order to produce cellulose pulp which has a desired kappa number. Thus, in the cooking stage, alkaline cooking liquor which originally was dosed into the absorption solution is used, but the temperature of which has been increased; absorption liquor is not removed, and fresh liquor is not fed into the boiler for continuous cooking or, it is fed, but only in a small amount.

EFFECT: disclosed is a method of defibring raw material.

18 cl, 2 dwg, 1 ex