HYDRODYNAMICS OF DISPERSED LIQUID DROPLETS IN AGITATED SYNTHETIC FIBROUS SLURRIES

The hydrodynamic and liquid particle dispersion processes in agitated vessels containing dilute liquid-liquid dispersions, and dilute liquid dispersions in synthetic fibrous slurries, were experimentally studie d, A transparent cylindrical vessel 25 cm in height and 15.5 cm in dia meter equipped with a six-blade impeller, with geometric proportions r epresenting the standard vessel configuration, was used. The steady-st ate size distributions of molten wax particles, which constituted 1% b y weight of the mixture everywhere, in pure water, and in aqueous slur ries with 0.1%, 0.5%, 0.8%, and 1.0% consistencies of nylon fibers, we re measured using sampling and microscopic image analyses, The average nylon fiber length and diameter were 6.22 mm and 19.5 mu m, respectiv ely. With pure water the molten wax particle size distributions were s patially homogeneous and bimodal everywhere and confirmed locally isot ropic turbulence in the vessel. In tests with fibrous slurries, for fi ber consistencies smaller than 1%, the molten wax particle size distri butions remained spatially homogeneous and agreed with the locally iso tropic turbulence assumption. However, they were unimodal everywhere w ith narrow particle diameter spectra. Increasing the fiber-consistency and impeller speed both lead to smaller mean molten wax particles and narrower particle diameter ranges, suggesting that fibers hamper part icle collision and coalescence. With 1% fiber consistency, widespread flow stratification and fiber flocculation took place.