THE SHEAR-THINNING PHENOMENON OF BAGASSE KRAFT BLACK LIQUOR FLUID

INTRODUCTIONKraft black liquor composition is very complicated. Generally, it is a complex and multiphase fluid, which consists of organic and inorganic components. The total solids content in black liquors has a great effect on its fluidity and deformation. To the wood black liquor, there have already been detailed researches on their flow properties and many theoretic or practical results have been concluded in the literatures 1-8]. But to non-wood black liquor, the previous researches…

THE SHEAR-THINNING PHENOMENON OF BAGASSE KRAFT BLACK LIQUOR FLUID

The flow curves of bagasse Kraft black liquor over a shear-rate range of 10-1s-1~103s-1 were investigated by using the Rheometric RFSII rheometer. Experimental results show that Bagasse black liquors are non-Newtonian fluids instead of Newtonian fluids at higher solids contents, and the viscosities of black liquor would decrease about 2~3 orders of magnitude with an increase in the shear rates. The apparent viscosity and flow behavior of bagasse black liquor are also affected by its solids content, and the higher solids content the more shear-thinning bagasse black liquor fluid is. In addition, the power-law equation was utilized to fit these flow curves at different conditions. Finally, the significances of shear-thinning properties of bagasse black liquor in the chemical recovery system, such as friction calculation of pipe and design optimization of the whole recovery system, were presented.