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: 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: A method of concentrating particles in a liquid-particle dispersion feed by adsorptive bubble separation by intimately contacting a gas with a pressurized stream of liquid in a chamber to form an aerated dispersion that retains at least some of the kinetic energy from the pressurized stream, and removing at least some of the kinetic energy from the aerated dispersion to form a dense foam. A liquid-particle dispersion feed is then injected into the dense foam to form a gas-liquid-particle dispersion. The gas-liquid-particle dispersion is injected into a flotation chamber at a point below a surface of a liquid contained therein, where the gas-liquid-particle dispersion forms bubbles of a gas-particle agglomerate, and the bubbles are released from the feed liquid depleted in hydrophobic particles and rise to the surface to form a floating froth enriched in particles.

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: 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 method of separating mixed particles in a flotation cell uses a fluidized bed within the cell where particles are fluidized in a quiescent zone by liquid moving upwardly through the fluidized bed. The fluidizing liquid may be provided by the feed or by recycling liquid from upper parts of the cell such as from the disengagement zone. Bubbles are introduced into the lower part of the cell through a mechanical impeller which also breaks up any channels in the mixing zone, or by separate aeration in the bottom of the cell or by introduction through a recycle pipe.

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: 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: The method relates to particle separation from a feed stream. The feed stream is injected directly into the froth zone of a vertical flotation column in the presence of a counter-current reflux stream. A froth breaker generates a reflux stream and a concentrate stream, and the reflux stream is injected into the froth zone to mix with the interstitial liquid between bubbles in the froth zone. Counter-current flow between the plurality of bubbles and the interstitial liquid facilitates the attachment of higher hydrophobicity particles to bubble surfaces as lower hydrophobicity particles detach. The height of the feed stream injection and the reflux ratio may be varied in order to optimize the concentrate or tailing stream recoveries desired based on existing operating conditions.

Abstract: The object is to remove unburned carbon in a fly ash in a stable and economically advantageous manner. A fly ash, water and a trapping agent are mixed together in a hybrid mixer (2), a shearing force is applied to the mixture to prepare a slurry containing surface-modified unburned carbon within a short time, a foaming agent is added to the slurry, and then the unburned carbon is separated by performing flotation separation in a flotator (11).

Abstract: The present invention is directed to flotation of refractory gold sulfide ores in which the ore is ground, floated, the tailings reground, and refloated to produce gold-bearing concentrates.

Abstract: Disclosed is a method for removing unburned carbon from fly ash at low cost and within a short time. The method comprises the steps of adding a collecting agent to fly ash directly, agitating/mixing the mixture in a mixer (5), adding water to the resulting mixed material in a mixing vessel (7) to yield a slurry, applying a shearing force to the slurry in a submerged stirrer (9), and performing flotation separation of unburned carbon in a flotator (15).

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: An oil sands flotation circuit wherein a feed stream is fed to a bank comprising at least one rougher flotation cell producing a rougher concentrate stream and a rougher tailings stream, said rougher concentrate stream being fed to a bank comprising at least one cleaner flotation cell producing a cleaner concentrate stream and a cleaner tailings stream.

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: A bitumen recovery process is provided which includes the step of providing a bitumen froth or a component derived from the bitumen froth as a feed material, wherein the bitumen froth is produced in a primary separation process from a slurry comprising oil sand and water. Further, the process includes the step of subjecting the feed material to froth flotation in a column flotation cell in order to recover a bitumen product from the feed material. Preferably, the froth flotation cell includes an underwash zone, wherein a bitumen-rich fraction of the feed material is passed through the underwash zone as the bitumen-rich fraction rises within the column flotation cell.

Abstract: A method and apparatus for recovering bitumen as froth from a feed stream having solids, water and bitumen is provided using a separating vessel having mounted thereon a downpipe assembly, the downpipe assembly having at least one downpipe and a nozzle in fluid communication with each downpipe, for aerating a stream of middlings withdrawn from the separating vessel and reintroducing the aerated middlings back to the separating vessel.

Abstract: An apparatus for processing bitumen froth comprising a cyclone body having an elongated conical inner surface defining a cyclone cavity extending from an upper inlet region with a diameter DC to a lower apex outlet with a diameter DU of not less than about 40 mm; an inlet means forming an inlet channel extending into the upper inlet region of said cyclone cavity; and a vortex finder forming an overflow outlet of a diameter DO extending into the upper inlet region of said cyclone cavity toward said lower apex outlet and having a lower end extending an excursion distance below said inlet channel, said excursion distance being operable to permit a portion of bitumen that passes through said inlet channel to exit said overflow outlet without having to make a spiral journey down said cyclone cavity, wherein a lower end of the vortex finder within the cyclone cavity is disposed a free vortex height (FVH) distance from said lower apex outlet.

Abstract: A process for separating phosphatic materials from coastal beach sand and sand deposits used for beach renourishment. The steps include (a) suspending a mixture of beach sand and phosphatic material in water, (b) introducing compressed gas, preferably air, into the mixture or sparging to produce a bubble froth on the surface of the water, and (c) skimming or separating the bubble froth from the surface of or within the water to effect separation of the phosphatic material in the froth from the beach sand left in the water. The bubbles of the bubble froth attract and carry the phosphatic material on the surface of the bubbles during upward movement through the mixture. A conditioner added to the water which improves the tendency of the phosphatic material to “float” is preferred.

Abstract: A hydrocyclone can be used for separating components of a fluid. The hydrocyclone can include a substantially open cylindrical vessel and a helical confined path connected upstream of the cylindrical vessel. The open vessel can include an open vessel inlet configured to introduce a fluid tangentially into the open vessel. The helical confined path can be connected to the open vessel at the open vessel inlet. One or more wash inlets can be used to introduce a wash fluid into the helical confined path and/or the open vessel. An overflow outlet and underflow outlet can be operatively attached to the open vessel for removal of the separated fluid components. Although a number of fluids can be effectively treated, de-sanding of bitumen slurries from oil sands can be readily achieved.

Abstract: Disclosed is a method for removal of an unburned carbon contained in a fly ash material. The method comprises the steps of adding water to the fly ash to prepare a fly ash slurry; shearing the fly ash slurry using an agitating blade that can rotate at a high speed to generate an active energy on the surface of an unburned carbon by the shearing force, thereby imparting lipophilicity to the unburned carbon; and adding a collecting agent and a foaming agent to the slurry containing the lipophylized unburned carbon to cause the attachment of the collecting agent to the lipophylized unburned carbon, and at the same time, causing the attachment of the unburned carbon having the collecting agent attached thereto an air bubble to separate the unburned carbon by flotation.

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: The invention provides a flotation device including a series of flotation tanks (1) for processing a slurry incorporating valuable minerals for extraction. At least one of the tanks includes a side outlet (15) adapted for the withdrawal of targeted relatively fine coarse particles from the slurry. The tanks also include a bottom outlet (14) for the withdrawal of relatively dense or coarse components of the slurry. The incorporation of bottom and side outlets allows the slurry to be separated into two parallel streams, one configured for optimal recovery of the relatively coarse or dense slurry components and the other for optimal recovery of the relatively fine slurry components. In this way, outflow slurry from downstream tanks in the coarse particle stream has a higher proportion of coarser particles than was present in the inflow slurry from the upstream tanks.

Abstract: A method and apparatus are presented for determining the quantity of liquid and solid content in a removal stream of a froth created from a suspension that is generated during a froth flotation operation. Specifically, electrodes are immersed in the froth generated from a suspension having a known quantity of fiber particles, and the conductance of the froth is measured to establish a relationship between the measured conductance and the quantity of fiber particles. The electrodes are then submerged in a froth generated from a suspension having an unknown quantity of fiber particles, and the froth conductance is measured. The quantity of fiber particles in the froth can then be determined from the pre-established relationship between conductance and solid particle content.

Abstract: In a process for beneficiating phosphate rock a slurry is provided having 30% to 70% by weight of a liquid phase and having a solid phase comprising clay, sand, and phosphate rock. In the process, the slurry is exposed to ultrasonic energy released from a sonotrode located within the slurry. The slurry may be exposed to the ultrasonic energy for less than 10 seconds. The ultrasonic energy may be produced by a piezoceramic transducer to have a resonance frequency within the range of from 16 kHz to 100 kHz. The ultrasonic energy may have an intensity within the range of from 0.0001 W/cm3 to about 1000 W/cm3. The ultrasonic energy may create cavitational forces within the slurry. After exposure to ultrasonic energy, clay and sand are separated from the phosphate rock, perhaps using an air flotation process and a cycloning process.

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: Embodiments of a method and a system for recovering energy, materials or both from asphaltene-containing tailings are disclosed. The asphaltene-containing tailings can be generated, for example, from a process for recovering hydrocarbons from oil sand. Embodiments of the method can include a flotation separation and a hydrophobic agglomeration separation. Flotation can be used to separate the asphaltene-containing tailings into an asphaltene-rich froth and an asphaltene-depleted aqueous phase. The asphaltene-rich froth, or an asphaltene-rich slurry formed from the asphaltene-rich froth, then can be separated into a heavy mineral concentrate and a light tailings. Hydrophobic agglomeration can be used to recover an asphaltene concentrate from the light tailings. Another flotation separation can be included to remove sulfur-containing minerals from the heavy mineral concentrate. Oxygen-containing minerals also can be recovered from the heavy mineral concentrate.

Abstract: Disclosed is a closed floatation conventional de-inking process adopted in the recycled paper processing plants, in which, ink separation and removal constitutes a major task. The specific concerns of this invention are the concept and the equipment for the separation and removal of the ink and ash from the pulp slurry contaminated with ink, clay and stickies.

Abstract: A process for separating phosphatic materials from coastal beach sand and sand deposits used for beach renourishment. The steps include (a) suspending a mixture of beach sand and phosphatic material in water, (b) introducing compressed gas, preferably air, into the mixture or sparging to produce a bubble froth on the surface of the water, and (c) skimming or separating the bubble froth from the surface of or within the water to effect separation of the phosphatic material in the froth from the beach sand left in the water. The bubbles of the bubble froth attract and carry the phosphatic material on the surface of the bubbles during upward movement through the mixture. A conditioner added to the water which improves the tendency of the phosphatic material to “float” is preferred.

Abstract: A process is described for the separation of fluorinated plastic particles from a mixture of solid particles of similar specific gravity. The process comprises mixing the particles with water, adding air to create bubbles, and generating two or more product streams, one of which floats and the other which sinks. The floating stream is enriched in fluoropolymer particles. Per pass yield and selectivity of fluorinated plastics are enhanced by the addition of a carboxylic acid to the froth flotation medium.

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 process for the separation of a multiple domain solid feedstock such as that derived from ASR, WSR, and/or ESR is disclosed which comprises granulating the feedstock to produce particles each of substantially a single domain, with each type of particle having a different density. The particles are introduced into a suitable aqueous salt solution. Aqueous salt solutions containing cations comprising sodium, calcium and ammonium, and anions comprising nitrate, bromide, and chloride are useful. A dispersion mixer having a high shear and/or turbulent zone is utilized to disperse agglomerated particles and a quiescent hydrogravity tank is utilized to effect binary separation of the mixture of particles into a stream with a higher average specific gravity, and a stream with a lower average specific gravity. A higher degree of product purity can be obtained by subjecting either of the product streams from the first hydrogravity stage to additional stages of hydrogravity separation.

Abstract: The machine productivity for a foam product is increased by increasing the surface of the enlarged upper part of the cylinder housing and by reducing material intensity by optimizing the dimensions thereof. This is obtained by determining the diameter of the enlarged housing part in the known machine which contains a cylinder housing consisting of an enlarged upper part and a lower part, and a feeder, ventilation and discharge device, embodied in the form of ejectors, a discharge device, and a foam collector container, with the aid of an equation according to the diameter of the lower part of the cylinder housing, the height of the cylinder housing and the height of the lower part of the cylinder housing. The foam collector container of the pneumatic flotation column is embodied in the shape of a gabled groove and is fitted with opposite connection parts used to discharge the foam product.

Abstract: A vortex grit trap comprising a generally vertically extending tank of circular cross-section including a separation zone having an inlet and an outlet for liquid flow to and from the tank, and in which liquid is circulated about a longitudinal axis of the tank, and, a grit collection zone positioned beneath the separation zone in use, the trap being characterized by a generally circular tank divider centered on the vertical longitudinal axis of the tank and extending transverse thereto, the divider defining a notional boundary between the separation and collection zones of the tank and being of smaller diameter than the adjacent region of the tank so as to define with the adjacent tank wall an annulus through which grit passes from the separation zone to the collection zone in use, and, means for generating a cloud of gas bubbles migrating in use upwardly through substantially the whole of said annulus whereby substantially all grit passing from the separation zone into the collection zone passes through the

Abstract: A metal or mineral compound collector for use in a froth flotation process so as to recover one or more desired minerals or metals; the collector comprising a functional group attached to a carbon chain; the functional group being a nitrile and the said chain having (11) or more carbon atoms. In a further form there is provided a method of recovering a metal or mineral compound from an ore comprising the steps of: wet grinding the ore to a desired particle size; adding water chemicals such as frothers or slurry-modifiers to the ground ore so as to prepare a slurry; adding an effective proportion of a collector comprising a functional group which has a carbon chain with a nitrile attached, said chain having (11) or more carbon atoms; supplying a gas stream to the slurry so as to generate a froth; and recovering the desired metal, mineral and/or sulphide thereof in the froth.

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: 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: An apparatus for separating bitumen from a bitumen froth output of a oil sands hot water extraction process comprises an inclined plate separator (IPS) for providing a first bitumen separation stage and a cyclone for providing a second bitumen separation stage. The cyclone overflow is recycled to the IPS inlet.

Abstract: A flotation separation system is provided for partitioning a slurry that includes a hydrophobic species which can adhere to gas bubbles formed in the slurry. The flotation separation system comprises a flotation separation cell that includes a sparger unit and a separation tank. The sparger unit has a slurry inlet for receiving slurry and a gas inlet to receive gas with at least enough pressure to allow bubbles to form in the slurry within the sparger unit. The sparger unit includes a sparging mechanism constructed to disperse gas bubbles within the slurry. The sparging mechanism sparges the gas bubbles to form a bubble dispersion so as to cause adhesion of the hydrophobic species to the gas bubbles substantially within the sparger unit while causing a pressure drop of about 10 psig or less across the sparging mechanism. The sparger unit includes a slurry outlet to discharge the slurry and the bubble dispersion into the separation tank.

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: The present invention relates to a method for producing cubic boron nitride abrasive grains used for producing a grinding wheel, etc., and to cubic boron nitride abrasive grains. The method comprises maintaining a mixture containing hexagonal boron nitride and seed crystals of cubic boron nitride under pressure and temperature conditions where cubic boron nitride remains thermodynamically stable, characterized in that the seed crystals contain cubic boron nitride twin crystals.

Abstract: A method of recovering a valuable component from a feed slurry in minerals processing plant for a mined material is disclosed. The method includes separating the feed slurry on the basis of particle size into at least two streams, of which one stream is a fines stream. The pH of the fines stream is then adjusted to be within a range in which contaminants on the surface of the fines are soluble so that contaminants dissolve from the surface of the fines. Thereafter, the valuable component is floated from the pH adjusted fines stream.

Abstract: A method and apparatus are presented for determining the quantity of liquid and solid content in a removal stream of a froth created from a suspension that is generated during a froth flotation operation. Specifically, electrodes are immersed in the froth generated from a suspension having a known quantity of fiber particles, and the conductance of the froth is measured to establish a relationship between the measured conductance and the quantity of fiber particles. The electrodes are then submerged in a froth generated from a suspension having an unknown quantity of fiber particles, and the froth conductance is measured. The quantity of fiber particles in the froth can then be determined from the pre-established relationship between conductance and solid particle content.

Abstract: A method for controlling operation of a flotation cell, where the liquid level and the foam level in the cell are measured and controlled. The method includes measuring at least one quality characteristic of the accept leaving the cell and determining the set value(s) for the liquid level and/or the foam level on the basis of the measured quality characteristic. The method is particularly suitable for flotation of a pulp suspension, particularly in deinking flotation.

Abstract: A method is provided for producing cubic boron nitride, in which a mixture containing hexagonal boron nitride and a catalyst is maintained under pressure and temperature conditions that thermodynamically favor the stable presence of cubic boron nitride, thereby forming composite lumps containing cubic boron nitride, which in turn are dissolved in an alkaline solution to recover cubic boron nitride. The method is characterized by including, prior to the dissolving step, a step of decreasing the ratio of low-pressure phase boron nitride to cubic boron nitride in the composite lumps down to 50% by mass or less.

Abstract: A concentration process of zinc silicated minerals, particularly willemite and calamine concentration, by single operations, or conventional steps of ore treatment, some of which include the following: Preparation of stockpiles of different mineralogical and contents compositions, crushing, screening, storage, dense separation, washing, homogenization, magnetic separation, grinding, classification, rubbing, conditioning, flotation, thickening, filtering, calcination, storage and waste deposition.

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.