National University of Science and Technology “MISiS”, Moscow, Russia:

V. D. Samygin, Leading Expert of a Chair of Mineral Processing, e-mail: visamiguin@yandex.ru

An important flotation intensifying way is a process, carried out in mineral particle adhesion to air bubble. The pulp flow passing through the ejector of multizone flotation machine (MFM) shows the equal and increased probability of nanobubbles isolation on hydrophobic surface of most particles. Activation is explained by the instantaneous rupture of water film between nanobubbles on the hydrophobic surface of the particles and the bubble, but not by its outflow. The conditions of adhesion activation during the MFM operation may be set depending on the performance (W) of pressure in front of the ejector (P). The conditions of activation formation for transparent two-phase flows (liquid-gas) in a certain area of P and W values were visualized by acquisition of typical “color of milk” to fine bubble flow. At the same time, the surface area in the unit of air volume is by 8.8–14.9 times more than the area, formed in other modes. A universal hydraulic dependence of the pressure P on the unit production capacity W is offered to use for opaque three-phase flows (solid – liquid – gas) as a criterion for the MFM operation mode. Increasing the air consumption and solid content decreased the unit production capacity. Increasing the air consumption also decreased the production capacity in two-phase flow (liquid-gas, L:G), and dependence in the liquid-solid flow (L:S) was extreme. The contributions of the phases were made for production capacity reduction for three-phase flows L:G:S, and the influence of air flow was more then the influence of solid.
This study was supported by the Russian Scientific Foundation, project No. 14-17-00393.

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