A novel process improves conventional and modified kraft cooking by pr
oducing two or more white liquors of chemical concentrations optimized
for the different phases of the cook. The process involves feeding th
e chips and hydrosulfite-rich liquor early in the cook followed by an
alkali-rich liquor or liquor later in the cook. The author presents re
sults of previous analytical and experimental work aimed at verifying
process benefits and describes the proposed liquor-making process in c
onceptual terms and practical process options.