FUNGAL TREATMENT OF ASPEN CHIPS FOR WOOD RESIN REDUCTION - A LABORATORY EVALUATION

Aspen, a hardwood species with a high resin content, is notorious for causing pitch deposition problems in kraft pulping. A laboratory evalu ation was conducted to study the effectiveness of a biotreatment proce ss for reducing wood resin in aspen chips prior to pulping. This treat ment involves inoculating wood chips with fungi that feed on wood resi n components. A commercial fungus, Cartapip 97, and Phlebia tremellosa were investigated. Fungal treatment resulted in a 15% additional remo val of wood resin in treated chips compared to untreated chips after t hree weeks of seasoning. analysis by gas chromatography showed signifi cant reductions of triglycerides and fatty acids. Problematic unsaponi fiable wood resin components, namely sterols, steryl esters, and waxes , were partially removed by the treatment, In addition to enhancing th e removal of most wood::resin component in aspen fungal treatment did not adversely affect the yield and physical properties of kraft pulps produced from treated chips.