Aa. Zaman et Al. Fricke, NEWTONIAN VISCOSITY OF HIGH SOLIDS KRAFT BLACK LIQUORS - EFFECTS OF TEMPERATURE AND SOLIDS CONCENTRATIONS, Industrial & engineering chemistry research, 33(2), 1994, pp. 428-435
The Newtonian (zero shear rate) viscosities of four different softwood
kraft black liquors from a four variable-two level factorially design
ed experiment for pulping slash pine were determined for solids concen
trations up to 84 % and temperatures up to 140-degrees-C (413.2 K). Me
thods of measurement and estimation of zero shear rate viscosities fro
m viscosity-shear rate data have been described and compared. The comb
ination of the absolute reaction rates and free-volume concepts were u
sed to express the relationship between the Newtonian viscosity and te
mperature. Attempts were made to obtain a generalized correlation for
Newtonian viscosity as a function of temperature and solids concentrat
ions. The results of this model and results of our previous empirical
correlation have been compared and discussed.