Abstract: According to the invention, there is provided a process for the beneficiation of coal discards by increasing calorific value and carbon content while removing inert mineral matter and sulphur compounds. The process involves the pretreatment of wash water with a non-ionic kinetically energized surface-active agent and the admixture with a fixed mass of raw coal discard to enhance hydrophobicity and carboniferous particle agglomeration. Processing of the resulting suspension though a dedicated series of spiral separators and high frequency, resonance sieves reliably reduces excessive levels of mineral ash and sulphur compounds.

Abstract: The present disclosure relates to an apparatus for generating nanobubbles of a gas in a liquid, the apparatus including: (a) an outer tube; (b) a porous inner tube coaxially located within the outer tube that is at least partially occluded so as to define one or more liquid flow paths through the inner tube; (c) a pair of end assemblies attached to respective first and second ends of the outer tube, each end assembly having an opening in fluid communication with the one or more liquid flow paths so as to allow a flow of liquid in an axial direction through the apparatus; and, (d) a gas inlet for allowing a flow of gas into a chamber formed between the outer and inner tube, the flow of gas permitted to permeate through the porous inner tube into the one or more liquid flow paths, wherein, as the gas permeates through the porous inner tube, nanobubbles of gas are generated which become entrained in the liquid flow.

Abstract: A method and apparatus for the recovery of hydrophobic particles from a slurry comprised of water, the hydrophobic particles, and a hydrophilic component. Slurry is exposed to a gas stream to permit bubbles to adhere to the hydrophobic particles. The slurry generally flows vertically through a vessel at a velocity that maintains gas hold-up at least between 30 and 70% to maintain a bubbly flow without a slurry froth interface so that a portion of the water of the slurry, together with entrained gas bubbles attached to hydrophobic particles, flows out of the vessel with a portion of the water of the slurry and the hydrophilic component remaining in the vessel. Water from the slurry and gas bubbles attached to hydrophobic particles flowing through the vessel is discharged and collected for processing. A portion of the hydrophilic component is extracted as tailings for disposal or subsequent processing.

Abstract: A method is described of mixing fluid materials, including solids and gases. The materials to be mixed are introduced between two cylindrical rotors mounted in parallel on a motorized shaft. The rotors have arrays of cavities on their cylindrical surfaces and rotate within close proximity to the interior of a cylindrical shell. Passage of the fluid between the rotating rotors and the interior surface of the cylindrical shell causes cavitation, which mixes the materials. The mixture is passed to outlets on the far sides of the rotors from the inlet. Apparatus is described for extending the flow path of the materials and thus increasing exposure to the cavitation process.

Abstract: A flotation plant includes a tank module which includes a self-supporting framework having an inner space. The tank module includes at least one flotation tank. The flotation tank is disposed in the inner space of the self-supporting framework. The tank module is a self-supporting unit capable of being transferable and hoistable as an integral entity. The flotation plant includes at least two drive units for the rotation of drive shafts, each drive shaft being connected to a rotor for mixing and/or forming bubbles in the flotation tank. An overflow receptacle is disposed at the level of the upper part of the tank module for receiving an overflow from the flotation tanks. The flotation plant includes an overflow channel which is connected to the overflow receptacle for receiving and conducting the overflow from the overflow receptacle to a pumping means. The overflow channel is disposed outside the tank module.

Abstract: A drive module which is a self-supporting structure being transferable and hoistable as an integral entity. The drive module includes a self-supporting framework having a shape of a rectangular parallelepiped. The self-supporting framework defines an inner space within the self-supporting framework. The drive module also includes at least two drive units. The drive units are supported to the self-supporting framework in the inner space of the self-supporting framework. The drive units are connectable to an external rotatable shaft for the rotation of the rotatable shaft located outside the drive module.

Abstract: A method is described of mixing fluid materials, including solids and gases. The materials to be mixed are introduced between two cylindrical rotors mounted in parallel on a motorized shaft. The rotors have arrays of cavities on their cylindrical surfaces and rotate within close proximity to the interior of a cylindrical shell. Passage of the fluid between the rotating rotors and the interior surface of the cylindrical shell causes cavitation, which mixes the materials. The mixture is passed to outlets on the far sides of the rotors from the inlet. Apparatus is described for extending the flow path of the materials and thus increasing exposure to the cavitation process.

Abstract: A method is described of mixing fluid materials, including solids and gases. The materials to be mixed are introduced between two cylindrical rotors mounted in parallel on a motorized shaft. The rotors have arrays of cavities on their cylindrical surfaces and rotate within close proximity to the interior of a cylindrical shell. Passage of the fluid between the rotating rotors and the interior surface of the cylindrical shell causes cavitation, which mixes the materials. The mixture is passed to outlets on the far sides of the rotors from the inlet. Apparatus is described for extending the flow path of the materials and thus increasing exposure to the cavitation process.

Abstract: The invention relates to floating equipment, for injection of a gas into liquid effluents or waste water, and more particularly of a gas rich in oxygen into a basin from the surface. The floating equipment has the following elements: a driving device, intended to be disposed over the liquid, provided with a vertical output shaft (8), equipped at its end with a propeller (6) immersed in the liquid; a pre-mixing device (5) comprising an injection device (7) positioned above or below a mobile aerator (9) with inclined blades, the propeller being situated at the end of the shaft, under the pre-mixing reactor.

Abstract: A flotation apparatus may include a flotation chamber having a side wall and a base, a stirrer, a sparging device associated with the stirrer, a first foam-collecting device arranged in an upper region of the flotation chamber for the purpose of collecting a foam product formed during the flotation process, and a charge line for charging the flotation chamber with pulp, wherein the charge line leads into the flotation chamber at a point above the stirrer and an ejector is present in the charge line. Further, a flotation method is performed in two stages inside a flotation chamber of a flotation apparatus, wherein an ejector is used in a first flotation stage and a stirrer is used in a second flotation stage.

Abstract: An apparatus and a method for removing unburned carbon from fly ash capable of suppressing facility cost and stably conducting performance adjustment depending on property of the fly ash. The method comprises the steps of: adding water to fly ash to produce slurry; adding collector to the slurry, feeding the slurry and the collector to a static-type mixer 4, a venturi pipe 24 or the like to add shearing force to them; adding frother to them to generate air bubbles; and adhering unburned carbon of the fly ash to the air bubbles to raise the unburned carbon. The frother and air can be fed to the static-type mixer or the like together with the slurry and the collector. Depending on the change in property of the fly ash, the number of the static-type mixers or the like used in series can be increased or decreased, and depending on required capacity, the number of the static-type mixers or the like used in parallel may be increased or decreased.

Abstract: At least one froth receiving device may be positioned in a slurry retained in a tank of a flotation cell of a flotation machine. Each of the froth receiving devices may be positioned adjacent to froth formed in the slurry by being positioned in the tank at a height that positions the froth receiving device in the froth or near the froth. Each froth receiving device may receive froth to extract the froth from the tank. In some embodiments, the extracted froth may be sent to at least one particle separation device so at least a portion of solid material in the froth is separated from liquid of the froth. The separated solid material may be moved to another machine for further processing for recovering the desirable material while any remaining solid material and liquid may be sent to another device for being utilized in further material processing.

Abstract: A pumpbox, the pumpbox being in fluid communication with one or more vessels, wherein the pumpbox comprises a classification portion and level control means adapted to control the level of fluid within the one or more vessels.

Abstract: Apparatus featuring synthetic bubbles or beads and a flotation stage. The synthetic bubbles or beads are configured with a polymer or polymer-based material functionalized to attach to the valuable material in a mixture to form at least some enriched synthetic bubbles or beads having the valuable material attached thereto, and also configured to be transported through the mixture based at least partly on a characteristic of the synthetic bubbles or beads. The flotation stage has the mixture containing valuable material, and is configured to receive the synthetic bubbles or beads and to provide the at least some enriched synthetic bubbles or beads having the valuable material attached thereto based at least partly the characteristic of the synthetic bubbles or beads.

Abstract: Apparatus for use in, or forming part of, a separation process to be implemented in separation processor technology, the apparatus comprising synthetic bubbles or beads configured with a polymer or polymer-based material functionalized to attach to a valuable material in a mixture so as to form an enriched synthetic bubbles or beads having the valuable material attached thereto, and also configured to be separated from the mixture based at least partly on a difference in a physical property between the enriched synthetic bubbles or beads having the valuable material attached thereto and the mixture.

Abstract: A method of controlling operation of a froth flotation cell comprises introducing gas into a liquid in the cell, thereby to create a froth on the surface of the liquid, which froth overflows and leaves the cell at an overflow point, wherein the froth has a froth height from the level of the overflow point to the upper surface of the froth, measuring values of the froth height for two values of gas flow rate into the cell, measuring values the velocity at which the froth overflows at the overflow point for two values of gas flow rate into the cell, calculating a gas flow rate into the cell that optimises gas recovery, by treating the measured values of froth height and measured values of froth velocity independently, and setting the gas flow rate into the cell to be the calculated flow rate into the cell that optimises gas recovery.

Abstract: A pneumatic flotation machine (100) has a housing (1) with a flotation chamber (3), at least one nozzle arrangement (4) for feeding gas and a suspension into the flotation chamber as well as at least one gassing arrangement (5) for feeding further gas into the flotation chamber (3), which arrangement is disposed within the flotation chamber (3) and below the at least one nozzle arrangement (4), wherein there is furthermore at least one adjusting device (9) for changing a position of the at least one gassing arrangement (5) in the flotation chamber (3).

Abstract: A housing of a flotation device has a flotation chamber with at least one inlet for a suspension. The flotation device has at least one foam collecting unit, arranged on an upper face of the housing, for receiving and discharging a foam product, and at least one fluid distribution element, provided above the at least one inlet in the flotation chamber, for generating a flow directed toward the at least one foam collecting unit. The vertical position of the at least one fluid distribution element is variable above the at least one inlet in the flotation chamber.

Abstract: The present invention provides an apparatus for waste sorting and uses thereof for the separation of said waste into organic and inorganic material, including processes for its use and in some embodiments subsequently producing biogas from said waste material.

Abstract: A flotation separation apparatus for separating particles in suspensions, feeds slurry containing the particles through an inlet into a contactor where gas is fed through an inlet to mix with the slurry, for example in a downwardly plunging jet, to form a gas-liquid bubbly two-phase mixture under pressure from an outlet restriction in a throttling duct. The mixture is passed through a flow manipulator configured to induce a high energy dissipation rate, for example by way of a Shockwave formed in a diverging section of the throttling duct reducing the size of the bubbles and brining those bubbles into intimate contact with particles in the mixture which is released into a separation cell where a flow manipulating draft tube is provided to reduce turbulence in the mixture. Alternative apparatus and methods for inducing the high energy dissipation rate and for reducing turbulence in the mixture are also described and claimed.

Abstract: A process for improving mined coal includes comminuting the coal to a particle size at which individual macerals are available. Reactive macerals are extracted from the comminuted coal as froth from the top of a deep-column flotation cell. The extracted macerals are then de-watered.

Abstract: A system and method utilize model-based control of a froth flotation process for concentrating a desired target mineral from ground ore. The system and method exploit real time information about a surface tension of a pulp or flotation solution including the minerals. The surface tension represents exemplary additional information about the surface chemistry in the flotation process, and as such enables a refinement of a pulp model used in control of the flotation process. Ultimately, operational efficiency of a froth flotation plant is increased.

Abstract: The invention provides a method of controlling operation of a froth flotation cell, the method comprising: introducing gas into a liquid in the cell, thereby to create a froth on the surface of the liquid, the froth having a depth from the surface of the liquid to an overflow point at which the froth overflows and leaves the cell; and controlling the froth depth to optimise the gas recovery with respect to the froth depth. Optimisation of the gas recovery with respect to the froth depth leads to the recovery of a froth concentrate of both high grade and high product recovery.

Abstract: Process and apparatus are described for adsorptive bubble separation of hydrophobic particles from liquid dispersions. When a gas-liquid-particle dispersion is introduced into a separation vessel, a baffle directs the rising bubbles toward the perimeter of the apparatus. At the liquid surface, bubbles with attached hydrophobic materials form a floating froth layer, which is directed toward a froth collection launder. Also disclosed is an improvement for froth flotation processes comprising using a vacuum to pull froth and/or collapsed froth into and through the froth collection launder and froth drain line.

Abstract: The present invention relates to an apparatus and a process for efficient hydrophobic particles to gas bubble attachment in a slurry is provided. The process comprises: tangentially introducing a slurry stream into a cylindrical chamber having a cylindrical inner wall with sufficient volume and pressure to develop a vortex in the flowing slurry; introducing gas into the flowing slurry during at least a portion of its travel in the chamber, the gas being introduced orthogonally to the stream through means located at the chamber inner wall and for developing gas bubbles which move into the slurry.

Abstract: The invention relates to an equipment and method for flotating mineral slurry (4) in a flotation cell provided with a flotation mechanism (3), comprising at least a drive shaft (6), a rotor (5) and a stator (7), and at least one inlet (11) for feeding mineral slurry (4), a froth launder system (8) for removing mineral enriched froth, at least two discharge outlets (28, 12) for removing two material flows with two different grain sizes from the flotation cell, in which case the flotation cell (2) is provided with a classifying equipment (1) including means for setting the mineral slurry (24) to be classified, separated from the mineral slurry, in an essentially upwardly moving rotary motion in the flotation cell, as well as means for separating coarser material (25) from finely divided material (26).

Abstract: In a froth flotation method and apparatus an upwardly open circular trough (4) having outlets (5) on the outer periphery of the trough is arranged horizontally above the froth phase (F) so that the trough is coaxial with the flotation vessel (1), and said circular trough is rotated around its center axis. A stationary water pipe (6) is arranged above the trough (4). Fresh water (W) is fed via the water pipe (6) into the trough (4) while the trough is rotating, and the water is let to flow by gravity and centrifugal force from the trough (4) via the outlets (5) into the froth phase (F).

Abstract: A froth flotation method and apparatus for extracting a valuable substance from a slurry comprising a mixture of solid phase, liquid phase and said substance. A gas dispersing mechanism (4) feeds gas into the slurry (1) in a flotation vessel (2) to infuse gas bubbles into the slurry. The slurry is agitated in the flotation vessel (2) for dispersing the gas bubbles into the slurry. The gas bubbles capture the valuable substance from the slurry and form a froth phase F above the slurry phase S. The froth phase F exits the vessel by overflow. Continuously moving negative pressure zones (7) are mechanically generated by rake blades (9) in the froth phase (F). The negative pressure zones (7) extend from the froth phase (F) to the slurry phase (S).

Abstract: An apparatus for separating a mineral from a slurry of mineral and impurities, including a fluid vessel having a first, open end and a second end and a feed well disposed near the first end. The feed well has a first, open end, for receiving the slurry, and a second end. At least one first member is received through the first ends of the vessel and the feed well for providing aerated water, creating a froth in the feed well including substantially the mineral. The mineral froth substantially separates from the impurities and floats out of the feed well towards the first end of the vessel, and a collection unit receives the mineral froth. The impurities and any remaining mineral fall toward the second end of the vessel. A measurement unit is placed within the vessel for measuring at least one of density and pressure of the fluid in the vessel.

Abstract: A flotation cell for separating hydrophobic particles from hydrophilic particles uses a mixer (1) with an air inlet (8) and slurry feed (7) to form a bubbly mixture in a u-tube mixer (4, 5, 6) and feed the mixture into a separation vessel (2). Plant cost and operating efficiencies are optimised by gravity feed of slurry and admitting air at atmospheric pressure. The separation vessel (2) has an upper inclined plate (9) which guides the froth layer (33) containing the hydrophobic particles to an overflow launder (11) without any significant turbulence or change in direction optimising the retention of hydrophobic particles in the froth, while the hydrophilic particles drop down in the liquid layer (34) guided along a lower inclined plate (24) to a tailings outlet (14).

Abstract: A flotation apparatus F includes a tank 1 for receiving a liquid raw material, and introduces air into the tank 1 to generate bubbles for adsorbing print ink in the liquid raw material to the bubbles, thereby floating and separating the print ink. The flotation apparatus F includes a circulating device for circulating the liquid raw material by raising and then lowering the liquid raw material in the tank 1, an air supply tube 4 for supplying air into the tank 1, and an agitating member 5 provided in the tank 1 for taking the air from the air supply tube 4 and agitating the air for forming the air into fine bubbles. The agitating member 5 has a rotary shaft 51 held horizontally and a plurality of members 52 horizontally separately provided around an outer periphery.

Abstract: Unburned carbon is efficiently separated according to the properties of fly ash. An apparatus is provided which comprises: a slurry preparation tank (10) in which water (c) is added to fly ash (a) to produce a slurry (d); a scavenger addition device (20) for adding a scavenger (e) to the slurry (d); a vertical surface-modification device (30) in which the slurry after addition of the scavenger is stirred at a high speed to impart shear force thereto and thereby cause the scavenger (e) to adhere to the surface of unburned carbon (b) contained in the slurry; a regulating tank (60) in which a blowing agent (f) is added to the slurry (d?) which has undergone surface modification with the surface modification device; and a flotation machine (70) with which the unburned carbon (b) is floated together with bubbles (n) and separated from the slurry containing the blowing agent.

Abstract: A procedure and apparatus for the concentration of hydrophilic materials through flotation which consists of two devices operating in series. The first device performs the function of feeding the gas and the pulp, generate bubbles and produce contact with the hydrophobic particles to be concentrated. The second device performs the functions of separating and evacuating the froth carrying the hydrophobic materials and the evacuation of the aqueous pulp with the materials with water affinity. The gas-pulp mixing device contains inside it solid mixing means, preferably bead shaped and of a density lower than that of the pulp to be processed. The generation of bubbles and their contact with hydrophobic materials happen when the gas and the pulp transit through the interstices between the mixing media which have discrete freedom to move in the interior.

Abstract: A method and a device for separating plastic materials in accordance with their chemical composition, which is based on the difference in density of such materials. For this purpose, a flotation process which works with a flotation liquid that is put into vibration is used, the frequency of which is controlled in accordance with the density of the particles to settle. Heavier plastic particles settle on a perforated plate bottom and are removed to a collecting container filled with the same liquid to the same level as the flotation tank. Lighter plastic particles float to the surface and are fed into a follow-up flotation tank for further separation.

Abstract: A method of controlling operation of a froth floatation cell for separating substances comprises introducing gas into liquid in the cell, creating a froth controlling gas flow rate into the cell in order to maximise gas recovery for the cell.

Abstract: A method and apparatus for introducing wash water into a flotation froth in a flotation separation system, where the wash water is injectioned into the froth in the form of a horizontal sheet of water. The sheet is typically formed by impinging a downwardly directed liquid jet issuing from a nozzle onto a horizontal plate or disc where it changes direction and travels radially outwards as an axi-symmetric planar liquid jet or sheet. The depth of the disc can be adjusted by a support rod. Other embodiments are described where the horizontal sheet is ejected through a horizontal slit, or where the sheet of wash water is rectangular rather than axi-symmetric.

Abstract: Separation of hydrophobic particles from a mixture of particles in a fluid is performed by providing a fluidized bed as a relatively non-turbulent contacting mechanism in a flotation cell incorporating a settling chamber located immediately above the fluidized bed. Hydrophobic particles attach to bubbles in the fluidized bed and rise to the interface with the settling chamber where non-hydrophobic particles flow over the lip of an internal launder and are removed as tailings at. The hydrophobic particles attached to bubbles float upwardly in the relatively placid settling chamber where unwanted gangue can fall back to interface. The bubbles form a froth layer at the upper surface of the settling chamber, and flow over the launder lip carrying the hydrophobic particles. An operation of the apparatus is kept stable by recirculating fluid from the settling chamber via pip and pump to mix with new feed entering at duct.

Abstract: Process and apparatus are described for adsorptive bubble separation of hydrophobic particles from liquid dispersions. The process may be used to treat the gas/liquid dispersion after it has been introduced from two or more ducts near the perimeter or from a central duct of the separation vessel. When the gas-liquid-particle dispersion is introduced from a central duct, the rising bubbles are directed by, e.g., a baffle toward the perimeter of the apparatus, where they rise. At the liquid surface, bubbles with attached hydrophobic materials form a floating froth layer, which is directed toward a central froth collection launder. Rising froth at the perimeter pushing the froth bed into the reduced area of the center encourages further coalescence of the bubbles and increases liquid drainage from the froth, thus leading to concentration of the collected materials without the need for complex equipment geometry.

Abstract: The invention concerns a method, device and computer program product for controlling a material separation process as well as to a material separating system. The material separating system comprises units separating desired material from undesired material, units measuring process output variables in the material separation process indicative of the degree of separation between desired and undesired material, a unit estimating the state of the process by applying the measured output variables and external constraints for a prediction time interval on a model of the material separation process, a unit optimising an objective function through maximising the recovery of the desired material in the separation process, which optimising provides at least one set point value for each input variable of the model, and at least one regulating unit regulating the separation process by using the set point value.

Abstract: An apparatus for separating a mineral from a slurry of mineral and impurities, including a fluid vessel having a first, open end and a second end and a feed well disposed near the first end. The feed well has a first, open end, for receiving the slurry, and a second end. At least one first member is received through the first ends of the vessel and the feed well for providing aerated water, creating a froth in the feed well including substantially the mineral. The mineral froth substantially separates from the impurities and floats out of the feed well towards the first end of the vessel, and a collection unit receives the mineral froth. The impurities and any remaining mineral fall toward the second end of the vessel. A measurement unit is placed within the vessel for measuring at least one of density and pressure of the fluid in the vessel.

Abstract: The disclosure relates to a process and device for aerating suspensions, particularly to flotate them, for example in deinking of pulp suspensions which includes a primary and secondary stage. In order to improve ash removal, a washing process is interposed between the primary and secondary stages.

Abstract: The invention relates to a stator for a flotation cell to be used in the flotation of slurry-like material, such as ore and concentrate containing valuable minerals, by means of which stator the orientation of the slurry flow created by the flotation cell rotor can be controlled. The stator is composed of at least three structural elements to be installed around the rotor provided with at least one flow regulator.

Abstract: The invention relates to a stator for a flotation cell to be used in the flotation of slurry-like material, such as ore and concentrate containing valuable minerals, said stator including flow regulators installed at regular distances from each other. The stator flow regulators are installed to be movable, so that the flow regulators can be adjusted at a desired distance from the rotor rotation axis.

Abstract: Discloses apparatus to perform a process to remove water and minerals from a bitumen froth output of a oil sands hot water extraction process. A bitumen froth feed stream is diluted with a solvent and supplied to a primary inclined plate separator stage, which separates the bitumen into an overflow stream providing a bitumen product output from the circuit and a bitumen depleted underflow stream. A primary cyclone state, a secondary inclined plate separator stage and a secondary cyclone stage further process the underflow stream to produce a secondary bitumen recovery product stream and a recycle stream. The secondary bitumen recovery product stream is incorporated into and becomes part of the circuit bitumen product output stream. The recycle stream is incorporated into the bitumen froth feed stream for reprocessing by the circuit.

Abstract: A method and apparatus for introducing wash water into a flotation froth in a flotation separation system, where the wash water is injectioned into the froth in the form of a horizontal sheet of water. The sheet is typically formed by impinging a downwardly directed liquid jet issuing from a nozzle onto a horizontal plate or disc where it changes direction and travels radially outwards as an axi-symmetric planar liquid jet or sheet. The depth of the disc can be adjusted by a support rod. Other embodiments are described where the horizontal sheet is ejected through a horizontal slit, or where the sheet of wash water is rectangular rather than axi-symmetric.

Abstract: An injector of a flotation cell, the injector comprising a feed pipe for feeding a fiber suspension flow into the flotation cell, a mixing apparatus for mixing air into the fiber suspension flow and at least one air feed connection arranged before the mixing apparatus for feeding air into the injector. The injector further comprises a nozzle section which is arranged before the mixing apparatus and comprises an aperture plate provided with apertures and nozzles fixed to the aperture plate substantially at the apertures after the aperture plate, there being open spaces between the nozzles. The air to be fed from the air feed connection is arranged to flow into the spaces between the nozzles and further into the mixing apparatus with the partial flows of the fiber suspension flow entering from the nozzles.

Abstract: A process of separating a desired constituent from a mixture of particulate matter including the steps of: conditioning a liquid mixture of particulate matter with a frothing agent to create a pulp; aerating the pulp to generate a float fraction of froth supported on the surface of a non-float fraction of pulp; separating a portion of froth from the float fraction; draining the separated froth; washing the separated froth with a liquid to dislodge particles comprising one or more of non-selectively attached, entrained, and entrapped particles; and recovering the washed froth, is disclosed herein. Also disclosed herein are a froth cleaning apparatus and a froth flotation apparatus for separating a desired constituent from a mixture of particulate matter.

Abstract: A process for aerating suspensions, particularly to flotate them, for example in deinking of pulp suspensions, with one or more stages and/or cells. Each stage/cell has its own separate liquid loop. A cleaner is interposed to improve removal of dirt specks.

Abstract: An apparatus for froth flotation including a flotation vessel including a side wall and a bottom wall that includes a fluid drain, and a mixing eductor inside the vessel disposed to impart net rotational force to contents of the vessel about an axis; and a method of separating a desired constituent (e.g., coal) from a mixture of particulate matter, including the steps of conditioning a liquid mixture of particulate matter including a desired constituent with a frothing agent to create a pulp, and injecting the pulp into a vessel to impart net rotational movement of pulp in the vessel, are disclosed.

Abstract: A froth flotation process typically used to separate particulate materials such as coal, has a mixed size feed (1) separated in a sieve bend (2) into a stream of relatively fine particles (3) and a stream of relatively coarse particles (14). The fine particles are fed to a flotation cell (7) in the normal manner, while the coarse particles are mixed with wash water (16) and distributed onto or into the froth layer (10) by wash water distribution apparatus (19, 20). Alternative variations of wash water distribution apparatus able to handle coarse particles are also described.