Shear-thinning properties of non-wood kraft pulping waste liquor

Abstract

The flow curves of Bagasse Kraft black liquor in a shear rate range of 10⁻¹–10³ s⁻¹ were investigated by Rheometric RFSII rheometer. In addition, the power-law equation was utilized to fit these flow curves at different conditions. The results show that Bagasse black liquors are non-Newtonian fluids instead of Newtonian fluids at higher solids contents, and the viscosities of black liquor decrease about 2–3 orders of magnitude with the increase of the shear rates. The apparent viscosity and flow behavior of bagasse black liquor are also affected by its solids content, and the higher the solids content is, the more the shear-thinning bagasse black liquor fluid is.

Keywords

non-wood Kraft pulping / waste liquor polymer solution / shear rate / shear-thinning / apparent viscosity / flow curves / chemical recovery / friction calculation

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