Abstract: A column flotation cell includes a fluid vessel, an exteriorly mounted microbubble generator, conduits for conducting a pressurized mixture of bubbles and liquid from the generator to the vessel, features for inhibiting the coalescence and enlargement of the bubbles prior to their introduction into the vessel, and an arrangement for introducing the bubble/liquid mixture into the vessel and for distributing the mixture uniformly throughout the vessel cross-section. Coalescence and enlargement of the bubbles are inhibited by limiting the length of the mixture-conducting conduits, and by designing the conduits so as to provide a substantially uniform and continuous flow diameter. The uniform and continuous nature of the flow diameter reduces local disturbances of fluid flow which would otherwise occur at discontinuities in the flow path, tending to cause coalescence and enlargement of the bubbles.

Abstract: A method and apparatus for generating microbubbles in a flowing liquid stream for use in a froth flotation system. The system utilizes a microbubble generator having a tubular housing with an inlet end and an outlet end. Located coaxially within the housing is an inner member with an elongated, tapered, exterior surface. A porous tubular sleeve is mounted between the housing and the inner member coaxially therewith to define with the cylindrical interior surface of the housing an elongated air chamber of annular cross section. The porous sleeve has a cylindrical inner surface that defines with the exterior surface of the inner member an elongated liquid flow chamber of thin, annular cross section. An aqueous liquid is supplied to the liquid flow chamber at a relatively high flow rate and air under pressure is supplied to the air chamber so that air is forced radially inwardly through the porous sleeve to be diffused in the form of microbubbles in the flowing stream.

Abstract: A froth flotation system for separating a mineral fraction from an aqueous pulp containing a mixture of mineral and gangue particles. The aqueous pulp is supplied to a pulp-filled vessel (or column) wherein a froth is formed on the surface of the pulp and collected in a launder. Gas bubbles are introduced into the pulp in the vessel by two different means to generate the froth. In accordance with one means, water is aspirated into a stream of pressurized gas (air) to form a stream of aerated water which is injected into the lower portion of the pulp-filled vessel. In accordance, the other means, a second stream of pressurized gas (air), is sparged through a porous wall of one or more micro-diffusers located within the vessel. The dual means for generating bubbles produces a significantly higher level of mineral separation than can be achieved from either means separately.

Abstract: The invention relates to the concentration and beneficiation of particulate matter by froth flotation and in particular to improvements in hydraulic-pneumatic flotation apparatus which contribute to the efficiency of operation. Such apparatus employs a constriction plate which separates vertically arranged flotation and hydraulic compartments. A discharge duct may be used to extend through the hydraulic compartment and to open through the constriction plate centrally thereof. Orifices in both the constriction plate are in communication with the hydraulic compartment to provide a uniform dispersion of air bubbles in the flotation compartment. Aerated water distribution manifolds within the hydraulic compartment and within the lower portion of the flotation compartment are provided to enter the aerated water into the flotation compartment substantially uniformly throughout a horizontal cross-section thereof.

Abstract: Improvements in flotation separating systems of the type employing small rising air bubbles to induce ascension of certain types of particles in a flotation compartment while other particle types descend toward the bottom of the compartment include a bubble passing, particle blocking barrier forming the bottom of the compartment separating the compartment from a source of air bubbles while allowing the introduction of a uniform distribution of air bubbles into the compartment in the form of a gently sloped conical plate having a plurality of aerated water passing apertures and an array of downwardly extending pocket forming baffles for limiting bubble migration along the slope of the lower plate surface. The baffles are generally configured as radially and circumferentially extending baffle portions.

Abstract: The invention relates to the concentration of particulate matter by froth flotation and in particular to improvements leading to the conservation of water. The apparatus includes an upstanding flotation compartment adapted to contain a relatively quiescent body of aqueous pulp. Aqueous pulp is introduced into and float fraction is collected from the upper portion of the flotation compartment, and hydraulic and aeration compartments are disposed near the bottom of the flotation compartment for aerating the water therein. A water-collecting compartment connected to the bottom of the hydraulic and aeration compartments is adapted to receive water from the latter. A tailings-discharge duct centrally of the flotation compartment extends through the hydraulic, aeration and water collection compartments to discharge fluidized tailings.