Kraft Pulping Properties of Acacia mearnsii and Eucalyptus grandis Grown in Zimbabwe

SYNOPSIS Pulpwood samples from 8-year old Acacia mearnsii and Eucalyptus grandis plantations grown in Zimbabwe were evaluated for kraft pulping, bleaching and papermaking properties. The possibility of co-pulping the two species was also investigated. A. mearnsii had higher chip basic density than E. grandis, and required more active alkali to produce less pulp. At about the same Kappa number, the A. mearnsii pulp had lower strength properties but higher opacity. Pulps of both species could be bleached to an acceptable brightness. The results demonstrated that the conventional prejudice against the use of A. mearnsii as pulpwood in Zimbabwe may be undeserved. The species has superior pulpwood productivity and can be successfully co-pulped with E. grandis, the preferred hardwood pulpwood species in Zimbabwe.