Battelle Memorial Institute

University of Kentucky Research Foundation

Bhupendra K Parekh

Harapanahalli S Muralidhara

Nagabhusan Senapati

John G Groppo, Jr

A froth flotation method and apparatus for the recovery of ultra-fine constituent are provided. The apparatus includes a flotation column having a drain for withdrawing tailings and underflow and an overflow for recovering the selected ultra-fine constituent. A mechanism is provided for delivering a wash medium to an upper portion of the column as well as for delivering diffuse air to a lower portion of the column. A slurry including the constituent to be recovered is received and conditioned within a tank that is connected by means of a feed line to the column. Additionally, a mechanism is provided for dissolving air in the slurry in the conditioning tank. Further, one or two matrixes may be mounted across the flotation column to further improve recovery. The method broadly includes the steps of (1) dissolving air in the slurry in the conditioning tank; (2) feeding the slurry through the feed line into an intermediate portion of the flotation column; (3) adding a reagent to the slurry that renders the selected constituent hydrophobic; (4) establishing and maintaining a downwardly flowing stream of wash medium in the flotation column; (5) establishing and maintaining an upwardly moving stream of diffuse air originating at a lower portion of the flotation column; and (6) recovering the selected ultra-fine constituent and diffuse air from the upper portion of the column.

Froth flotation method for recovery of ultra-fine constituent

A method of separating a solid-liquid suspension (e.g. an aqueous coal suspension, a suspension of clay in oil) by concurrently subjecting the suspension to the action of a sonic or ultrasonic field and an electrical field so as to remove the liquid from the suspension. The suspension is moved into a solid-liquid separation chamber between opposing electrodes one of which is permeable to the liquid. The sonic or ultrasonic field is then applied to the suspension concurrently with the electrical field, at a frequency and amplitude adapted to cause the liquid to separate from the suspension particles. The concurrently applied electrical field between the electrodes causes the particles to migrate away from the permeable electrode and liquid to migrate toward the permeable electrode. The liquid is then removed through the permeable electrode. The method requires less energy to remove a unit of liquid, has a faster rate of liquid removal and achieves a lower liquid content than if only an electrical field or acoustical field were used separately or in sequence.

Solid-liquid separation process for fine particle suspensions by an

A method of dewatering an aqueous suspension by concurrently subjecting the aqueous suspension to the action of a sonic or ultrasonic field and an electrical field so as to remove the water from the suspension. The suspension is moved into a dewatering chamber between opposing electrodes one of which is permeable to water. The sonic or ultrasonic field is then applied to the suspension concurrently with the electrical field, at a frequency and amplitude adapted to cause water to separate from the suspension particles. The concurrently applied electrical field between the electrodes causes the particles to migrate away from the permeable electrode and water to migrate toward the permeable electrode. Water is then removed through the permeable electrode. The method requires less energy to remove a unit of water, has a faster rate of water removal and achieves a lower moisture content than if only an electrical field or acoustical field were used separately or in sequence.

Growing community of inventors

Lexington, KY, United States of America

Bhupendra K Parekh