Pulping, Black Liquor and Papermaking Characteristics of Plantation Grown E. Camaldulensis and E. Viminalis, 1997 Pulping Conference Proceedings

Eucalyptus camaldulensis and Eucalyptus viminalis species were planted in separate blocks about the Simpson Paper Company properties in Shasta County, California in 1986. In 1988, plantings which would eventually cover over 4,000 hectares were begun 100 km south of the mill near Corning and Oat Creek in Tehama County. Laboratory studies in 1994-95 provided the background data for a four-day Eucalyptus pulping and papermaking trial in January 1996. The primary objectives of the trial were to determine pulp mill equipment capabilities, to evaluate evaporator and recovery boiler operations, to determine Eucalyptus black liquor chemical and firing characteristics and to determine the effect of vessel segments in various coated paper grades. Vacuum drum washers require modification to successfully process the Eucalyptus fiber. Trial black liquor fired without difficulty, although measured black liquor viscosity was 600 mPa-sec at 70% dry solids and 100° C. The metals concentrations in black liquor and recovery furnace ash were higher during the Eucalyptus trial than on regular mill softwood chips. Eucalyptus bleached pulp quality was excellent. Coated paper quality with 35 to 55% Eucalyptus furnish was identical to control papers. Vessel segment picking was not found in commercial printing evaluations.