IMPROVED MODIFIED KRAFT COOKING .4. MODIFIED COOKING WITH IMPROVED SULFIDE AND LIGNIN PROFILES

Details of a new modified kraft cooking process with a high initial su lfide concentration have earlier been reported /1/. This paper reports on the effect of an additional step aiming at decreasing the lignin c oncentration towards the end of the cook. This is achieved through dra inage of the free liquor followed by the addition of fresh liquor at a point (H-factor 1200) in the final phase of the cook. The modificatio n results in an increase of approximately 90 units in pulp viscosity a t a given kappa number.