To provide a method for producing chemical cellulose pulp with reduced pulp slag of hardwood at a given Kappa number.

The invention relates to the method for continuously producing chemical cellulose pulp from a slurry of comminuted hardwood material wherein (a) the slurry of comminuted hardwood material is subjected to a first cooking stage under conditions sufficient to reduce syringyl lignin (s-lignin) content in the hardwood material as compared to guaiacyl lignin (g-lignin) content therein, and thereafter subjecting the slurry of comminuted hardwood material to a second cooking stage under conditions sufficient to reduce the g-lignin content remaining therein after the first cooking stage.

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