Abstract: The invention relates to a method of using a flotation machine that is used in metallurgical processes and to a flotation machine. The flotation machine foams hydrophobic particles from an aqueous slurry that contains these particles. The flotation machine includes a flotation cell (1), and a rotor (2) that is inside the flotation cell. The rotor (2) is rotated at a mixing power, which maintains the suspension in the slurry and mixing of air with the slurry to form the foam, and the mixing power is controlled by adjusting the rotation speed of the rotor. The amount of solid matter S accumulated on the bottom of the cell (1) is determined, and the rotation speed of the rotor (2) is adjusted on the basis of the determined amount of solid matter. The flotation machine includes a measuring device (5) for determining the amount of solid matter accumulated on the bottom of the cell.

Abstract: The invention relates to a mixing device and method by means of which two solutions that are insoluble or poorly soluble in each other are mixed together into a dispersion. The device consists of at least three helical bars rotating upwards around a shaft and supported on it, so that the support structures between the shaft and the helical rods are set essentially in a horizontal position. The device and method are particularly suitable for mixing solvent extraction solutions used in the hydrometallurgical recovery of metals to form a dispersion.

Abstract: A method for manufacturing a cooling element for a metallurgical furnace, wherein there is arranged a frame element mainly made of copper and provided with water cooling channels; in the frame element, there are arranged fastening elements for connecting refractory bricks to the frame element; and refractory bricks are connected to the frame element by using fastening elements; and wherein the fastening elements are at least partly formed of elongate steel fastening strips; the method comprising fastening the elongate fastening steel strips to the frame element so that the elongate fastening steel strips together form in between them an open interspace, which is narrowed in a direction pointed away from the bottom of the open interspace; and arranging refractory bricks in the open interspace so that the refractory bricks are located at least partly in the open interspace.

Abstract: A process for producing metal oxide from a metal salt includes supplying a first part of the metal salt to a hydrate drier so as to indirectly heat the first part of the metal salt in the hydrate drier using a heat transfer medium from a first stage of a multi-stage indirect cooler so as to dry the first part of the metal salt in the hydrate drier and so as to control a waste gas temperature of the process. A second part of the metal salt is guided as a partial stream past the hydrate drier. The metal salt is preheated in a first preheating stage and precalcined in a second preheating stage. The metal salt and a fluidizing gas having a temperature of 150° C. or less are supplied to a fluidized bed reactor so as to calcine the metal salt to form a metal oxide product. The metal oxide product is cooled in at least one suspension heat exchanger and then in the multi-stage indirect cooler.

Abstract: The invention relates to a method and equipment for starting up a strand sintering furnace (1). During start-up, the sintering furnace is heated in order to create suitable production temperatures in the different process zones (I-VII) having different temperatures, said zones including a drying zone (I), a heating zone (II), a sintering zone (III), an equalizing zone (IV), a first cooling zone (V), a second cooling zone (VI) and a third cooling zone (VII). During start-up, the cooling gas to be conducted to the second cooling zone (VI) is heated by means of a heating device (3) up to a temperature that is higher than the ambient temperature.

Abstract: The present invention concerns a mixer-settler, an arrangement comprising a train of at least two mixer-settlers and a method for measuring and controlling volumetric O/A ratio and phase disengagement time of organic and aqueous phases in a dispersion. A continuous flow of dispersion is led via an inlet channel (6) from the uptake channel (4) though a measurement chamber (5) to an outlet channel (9) which leads the flow to the pump-mixer unit (1). At predetermined time intervals the continuous flow of dispersion is interrupted by closing the inlet and outlet valves (12, 13) to retain a sample of dispersion in the measurement chamber (5) for the measurement of the O/A ratio and phase disengagement time.

Abstract: A vibrating machine for producing a molded body by compacting a granular raw mixture includes an oscillatable vibrating table configured to receive a molding box. A clamping device is produced by at least two clamping closures, each including: a pivot bracket having a lower end being pivotally mounted on the vibrating table and an upper end including a cranking which is directed outward; a double-acting hydraulic pivot cylinder pivotally mounted on the vibrating table; a two-armed rocker arm pivotally connected to the pivot bracket and including an inner part that cooperates with the molding box and an outer part that cooperates with the hydraulic pivot cylinder; and a compression spring disposed between the cranking and the outer part of the rocker arm such that the rocker arm releases from a position closing the respective clamping closure upon a pressure in the hydraulic pivot cylinder being relieved.

Abstract: The invention relates to a method and equipment for the continuous sintering of mineral material in a sintering furnace (S). In the method, a material bed (2) is formed on a conveyor base (1), the material bed (2) is conveyed by the conveyor base (1) through the process zones (I-VII) of the sintering furnace that have different temperatures, the zones including at least one drying zone (I), at least one cooling zone (VII), and at least one other process zone (II, III, IV, V, VI) between the said drying zone and cooling zone, and gas is conducted through the conveyor base and the material bed (2), when the material bed travels through the process zones (I-VII), and gas is circulated in a circulation gas duct (3) from the last cooling zone (VII) to the drying zone (I). Part of the gas flow that is conducted to the drying zone (I) in the circulation gas duct (3) is removed as an exhaust gas flow (B) by the exhaust gas blower (5) of an exhaust gas duct (4).

Abstract: A process for producing hot metal includes partially reducing granular raw materials containing iron oxide with a carbonaceous reducing agent in a fluidized bed reactor at a temperature of at least 850° C. so as to obtain a reduced mixture. The reduced mixture is cooled to between 600° C. and 800° C. in a heat exchanger apparatus using a preheated process gas as a cooling medium that is preheated to between 300° C. and 500° C. before being introduced into the heat exchanger apparatus. The reduced mixture is then supplied to a smelting reduction unit via a discharge system.

Abstract: The invention relates to a system used in the liquid-liquid extraction of metals, enabling the amount of organic solution required in the various stages of extraction to be significantly reduced. In accordance with the invention, the settler unit of one step belonging to an extraction system is selected to function also as the organic solution storage and pumping tank.

Abstract: The invention relates to a method for recovering gold by solvent extraction from an acidic chloride-containing aqueous solution or from slurry containing gold-bearing solids using a diester-based reagent that is poorly soluble in water as organic extraction solution. In accordance with the method, gold is extracted extremely effectively, but other precious metals and many other metals quite sparingly. Gold is stripped from the extraction phase with pure water, from which the gold can be reduced either chemically or electrochemically.

Abstract: The invention relates to a suspension smelting furnace comprising a reaction shaft (1), an uptake shaft (2), and a lower furnace (3), as well as a concentrate burner (4) for feeding reaction gas and fine solids into the reaction shaft (1) of the suspension smelting furnace. The concentrate burner (4) comprises a fine solids discharge channel (5) that is radially limited by the wall (6) of the solids discharge channel, a fine solids dispersion device (7) in the fine solids discharge channel (5), an annular reaction gas channel (8) that surrounds the fine solids discharge channel (5) and is radially limited by the wall (9) of the annular reaction gas channel (8), and a cooling block (10) that surrounds the annular reaction gas channel (8). The cooling block (10) is a component that is manufactured by a continuous casting method.

Abstract: A grinding mill includes a mill body defining a grinding cavity, the mill body supported at opposing sides by respective bearings, a motor, operable to drive the mill body and arranged adjacent to at least one bearing, and a torque transmitter. The torque transmitter has a diameter smaller than the diameter of the grinding cavity and larger than the diameter of the bearings.

Abstract: A process for lowering the carbon content in ash includes introducing the ash having a carbon content of 1 to 20 wt.-% into a reactor where the ash is burnt at a temperature between 700 and 1100° C. Fuel is also introduced into the reactor. During combustion, microwave radiation is fed into the reactor. At least part of the energy released during the combustion is recovered.

Abstract: The invention relates to a method for leaching a material containing a valuable metal and precipitating the valuable metal as a fine-grained powder by changing the electrochemical potential of an intermediary metal in the solution. In the leaching stage the intermediary metal or substance of the electrolyte solution is at a high degree of oxidation and in the precipitation stage another electrolyte solution is routed into the solution, in which the intermediary metal or substance is at a low degree of oxidation. After the precipitation stage the solution containing the intermediary is routed to electrolytic regeneration, in which part of the intermediary is oxidised in the anode space back to a high potential value and part is reduced in the cathode space to its low value.

Abstract: A method and apparatus for converting an iron-bearing residue generated in a hydrometallurgical process that contains small amounts of soluble heavy metals into a stable form by means of a neutralising agent. The residue is elutriated and the elutriated residue is fed into at least one stabilisation or homogenisation reactor, into which a neutralising agent is also routed, and the homogenous mixing together of the residue and neutralising agent takes place by means of a helix mixer, where the ratio of the diameter of the mixer to the diameter of the reactor is 0.75-0.99.

Abstract: In a method of charging fine-grained metals, in particular directly reduced iron (DRI), into an electric-arc furnace (1), the metal is supplied via a downpipe (12) to an opening (10) provided in the furnace roof (4), is introduced into the furnace (1) through this opening (10) as bulk material stream (11), and falls onto the melt (13) merely by gravity. Further, an electric-arc furnace (1) suited for this purpose is described. A rather loss-free introduction even of fine-grained material having a mean grain size of less than 1 mm is achieved by passing the bulk material stream (11) through a dosing orifice (8) after the downpipe (12) and before entering the furnace (1). The bulk material stream (11) then enters the furnace essentially undisturbed.

Abstract: The present invention describes a method, apparatus and computer program for detecting the locations of boundaries between different materials in a desired measurement volume. The apparatus uses at least one measuring probe, the electrodes of which are characterized in that they together form an assembly that differs from a straight line. In addition, a volume at a further distance from the assembly can also be observed by the assembly, so that measurements can be conducted remotely and, on the other hand, the apparatus stays unbroken in diverse measurement situations. By using the EIT-measurement and applying for example a so-called 1D-?-method or methods of machine learning, electrical conductivity distributions in the measured volume are detected. As a result, the locations of the possible boundaries between different materials or for example thicknesses of different material layers are detected.

Abstract: The invention relates to a method for thermally processing ?-spodumene, i.e. lithium aluminum silicate, by which treatment it is transformed into ?-spodumene, which is more advantageous for further processing; in the method, concentrate or ore with a grain size of 20-1,000 ?m is processed in a fluidized bed reactor, at a temperature of 800-1,000° C., by using an oxygenous gas as the fluidizing gas.