Kraft pulping of softwood chips with mild hot water pre-hydrolysis to understand the effects of wood chip thickness

Hemicelluloses consume alkali during kraft pulping and dissolve in the black liquor as a low energy fuel. Acidic pre-hydrolysis of softwood chips removes hemicelluloses but preserves cellulose content prior to pulping. This study compared mild (140 °C) with conventional commercial at two H-factors for wood thickness ranging from less than 2 mm over 6 mm. The chip increased oligomer yield showed little influence on pulp fiber yield. However, length decreased 5.6%. Kappa number reject dramatically when was greater detailed compositional analysis quality indicate that followed by enhanced delignification limited reduction width, kinks. Strategic considerations integration into future biorefineries were outlined.