A device and method for cleaning contaminated solid-liquid mixtures by removing impurities and contaminants from an aqueous paper fiber suspension by flotation. Apparatus includes a first conduit (2) for a liquid, a second conduit (3) for a solid-liquid mixture, a third conduit (4) connecting first and second conduit (2, 3), a Venturi mixing element (5) with cones (7, 11), having small through-opening into chamber (9) which forms a cavity with small through-opening (12, 13) of the cones; the through-opening of first cone (7) connected with first conduit (2) and the rough-opening connected to second conduit (2), the small through-opening (12) of first cone (7) and the non-conical conduit sections arranged in longitudinal axial alignment, a fourth conduit (6) for conveying gas, wherein the fourth conduit (6) opens to the Venturi mixing element (5), and a fractionator arranged downstream of the second conduit (3) for removing the foam produced by flotation.

The present invention comprises a process and apparatus for separation of hydrocarbons from hydrocarbon-containing produced water, wherein in stage 1 the hydrocarbon-containing produced water is supplied with a gas-containing component, whereupon a gas- and hydrocarbon-containing produced water mixture is fed to an inlet tube (22, 27) in the center of a tank, whereupon the said mixture is tangentially distributed via at least one nozzle (7) and at least one baffle plate (8.1), whereupon separated hydrocarbons are conveyed to at least one outlet from the tank and cleaned water is conveyed to an outlet (12) from the tank.

A fluidized-bed flotation unit, its use, a mineral processing apparatus, and a fluidized-bed flotation method are disclosed. The fluidized-bed flotation unit includes a tank for holding a volume of slurry. The tank includes a launder with a launder lip, a fine slurry outlet below the launder lip, and a coarse slurry outlet below the fine slurry outlet for discharging coarse output slurry from the volume of slurry. The fluidized-bed flotation unit includes a solid-liquid separation arrangement configured to collect output slurry from the volume of slurry via the fine slurry outlet and to separate suspended solids and flotation liquid from the output slurry to form a solids portion and a liquid portion.

A dissolved air floatation apparatus including an ultrafine bubble-containing liquid production device and a dissolved air floatation tank. The ultrafine bubble-containing liquid production device includes a gas-liquid mixing unit and a bubble-containing liquid separation device. The bubble-containing liquid separation device swirls a liquid containing ultrafine bubbles and larger bubbles in a storage tank to concentrate the liquid that contains the ultrafine bubbles and the liquid that contains the larger bubbles to a central part of the swirling flow followed by discharge. A pressurized ultrafine bubble-containing liquid is mixed in a raw liquid containing a subject to be cleansed and is poured into the dissolved air floatation tank to cause a suspended substance and a dissolved component in the raw liquid to be adsorbed on an interface of fine bubbles and be floated in the dissolved air floatation tank to be extracted.

Apparatus uses hydrophobic synthetic beads to recover mineral particles in a slurry. The synthetic beads and the slurry are mixed into a mixture for processing. The apparatus has an interaction vessel installed in a section of pipeline. The interaction vessel is made from a pipeline folded or coiled into a compact struction having a continuous flow path. The interaction vessel has an input to receive the mixture of slurry and synthetic beads. The folded or coiled structure is used to increase the residence time of the mixture in the flow path, allowing more time for the mineral particles in the slurry to attach to the surface of the synthetic bead, while maintaining a small footprint. The interaction vessel may be formed from a number of loops of pipe section. The interaction vessel may be formed from one or more folded structures.

A method of removing metal particles from a contaminated metalworking fluid comprising emulsion droplets and metal particles includes pressurizing a first clean metalworking fluid with gas to provide an aerated metalworking fluid; releasing the pressure of the aerated metalworking fluid to form a plurality of bubbles; applying a shear force to the contaminated metalworking fluid to separate the emulsion droplets from the metal particles; flowing the contaminated metalworking fluid with the aerated metalworking fluid in a laminar flow to form a combined fluid, wherein the flowing occurs during the formation of the plurality of bubbles and while the emulsion droplets are separated from the metal particles, and wherein the laminar flow lasts for a time sufficient for the plurality of bubbles to attach to the metal particles; releasing the combined fluid into a flotation tank; and removing the metal particles to form a second clean metalworking fluid.

A method of removing metal particles from a contaminated metalworking fluid comprising emulsion droplets and metal particles includes pressurizing a first clean metalworking fluid with gas to provide an aerated metalworking fluid; releasing the pressure of the aerated metalworking fluid to form a plurality of bubbles; applying a shear force to the contaminated metalworking fluid to separate the emulsion droplets from the metal particles; flowing the contaminated metalworking fluid with the aerated metalworking fluid in a laminar flow to form a combined fluid, wherein the flowing occurs during the formation of the plurality of bubbles and while the emulsion droplets are separated from the metal particles, and wherein the laminar flow lasts for a time sufficient for the plurality of bubbles to attach to the metal particles; releasing the combined fluid into a flotation tank; and removing the metal particles to form a second clean metalworking fluid.

A flotation cell for treating particles suspended in slurry. The flotation cell includes a fluidized bed, a recovery zone at the upper part of the flotation cell, a launder lip and a recovery launder, and a tailings outlet. A primary slurry feed including fresh slurry is arranged to be fed into the flotation cell by a first feed inlet at a first position; and a secondary slurry feed including at least slurry recirculated from a flotation cell is arranged to be fed into the fluidized bed by a second feed inlet at a second position, below the first position. The slurry recirculated from the flotation cell is obtained at a third position between the recovery launder and the tailings outlet. A use of the flotation cell as well as a method for treating particles suspended in slurry are also disclosed.

A flotation cell for treating particles suspended in slurry. The flotation cell includes a fluidized bed; a recovery zone at an upper part of the flotation cell; a launder lip and a recovery launder; a tailings outlet arranged below the recovery launder; and a first feed inlet arranged to supply a primary slurry feed comprising fresh slurry into the fluidized bed at a first position. The flotation cell has a height measured from the bottom of the flotation cell to the launder lip. The flotation cell includes an agitator arranged adjacent to the bottom of the fluidized bed.

The present invention relates to apparatus for simultaneous grinding and froth flotation of at least one crude mineral and/or pigment, a process carried out in the apparatus for manufacturing at least one ground mineral and/or pigment, use of the ground mineral and/or pigment bearing phase obtainable by the process in paper applications as well as in paper, plastics, paints, coatings, adhesives, sealants, food, feed, pharma, concrete, cement, cosmetic, water treatment and/or agriculture applications, preferably in a wet end process of paper machine, in cigarette paper, board, and/or coating applications, or as support for rotogravure and/or offset and/or ink jet printing and/or continuous ink jet printing and/or flexography and/or electrophotography and/or decoration surfaces and the ground mineral and/or pigment bearing phase or ground mineral and/or pigment obtainable by the process.