Abstract

The influence of black liquor composition and solids concentrations on the Newtonian viscosity of slash pine black liquors over wide ranges of temperature (up to 140 °C) and solids concentrations (between 50% and 83% solids) has been studied. It was found that the zero shear rate viscosity of high solids black liquors depends strongly on the cooking conditions and/or black liquor composition. Not only is high solids viscosity affected by lignin molecular weight and lignin concentration in the liquor but other organic and inorganic constituents of black liquor also make a significant contribution to viscosity. The dependency of zero shear rate viscosity on solids concentrations, and temperature is defined. The Newtonian viscosities vary over a wide range depending on temperature, solids concentrations and solids composition. The results indicate that, at fixed levels of effective alkali and sulfidity, the zero shear rate viscosities can be described as a function of both lignin concentration and lignin molecular weight. The viscosity of black liquor is an increasing function of the organics-to-inorganics ratio and is a decreasing function of the concentration of sodium and chloride ions and pH of the liquor.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.