Elma-Asterion Group of Companies, St. Petersburg, Russia:
A. N. Grigorieva, General Director, Candidate of Technical Sciences, e-mail: an@td-elma.ru

St. Petersburg State Technological Institute (Technical University), St. Petersburg, Russia:

R. Sh. Abiev, Head of the Chair for Optimization of Сhemical and Biotechnological Equipment, Professor, Doctor of Technical Sciences, e-mail: rufat.abiev@gmail.com

The efficiency of the process of thickening the products of enrichment of non-ferrous metal ores largely depends on the particle size in the pulp, therefore, flocculants are used to intensify the thickening of fine pulps. In the process of mixing, it is important to evenly distribute the flocculant solution over the entire volume of the pulp and not to destroy the formed flakes by excessive shear stresses of the mixer. The process of flocculation during mechanical mixing of the pulp with concentrated solutions of the flocculant is considered. The previously developed method, based on the semi-empirical Prandtl turbulence model, for selecting mixing devices, taking into account agitator`s geometry, was confirmed. It has been established that the choice of the optimal rotational speed of the agitator is related to the magnitude of turbulent friction stresses created by the agitator`s blades. The results of experimental studies on mixing a suspension with a high-molecular flocculant Greenlife K40 of cationic action using different types of mixing device are presented. The comparison was made between traditional turbine and three-bladed agitators, as well as the developed conical agitator with a new geometry. The efficiency of the mixing devices was determined by comparing the size of the formed flakes. It has been established that larger and stronger flakes are formed in the case of using a conical mixer.

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