Abstract: An object of the present invention is to provide a mold powder for continuous casting of steel whose fluorine content is small, and which enables stable casting, for reducing the corrosion of continuous casting equipment and decreasing the concentration of fluorine in the waste water, well as a method for continuous casting of steel using mold powder. The mold powder for continuous casting of steel of the present invention is characterized by having a chemical composition including 25 to 70 wt % of SiO2, 10 to 50 wt % of CaO, not more than 20 wt % of MgO, and 0 to 2 wt % of F as an unavoidable impurity, where the viscosity of the molten mold powder is not less than 4 poise at 1,300° C.

Abstract: A fine-grained product with a grain size of 100%<5 mm is obtained during the production of titanium dioxide in the chloride method in which titanium-containing raw material is reacted with gaseous chlorine in the presence of a carbon-rich substance, preferably coal and/or coke, in a chlorination reactor, preferably with a fluidized bed, to form titanium tetrachloride, the fine-grained product consisting, in the dried state, of the main constituents TiO2, coal and SiO2, mixed with filter salt (iron sulfate that is obtained during dilute acid recovery), residues containing TiO2 from TiO2-production according to the sulfate method, coal, sulfur, and ilmenite/TiO2-slag. This mixture is treated in a fluidized bed furnace or rotating tubular furnace at temperatures of 900 to 1,300° C. The mixture is used as a flux for the purpose of improving the durability of the brick lining of a furnace for the smelting-metallurgical production of metallic materials.

Abstract: Metal baghouse dust can be solidified and thereby used for a variety of different purposes including a binder material by blending the electric arc furnace dust with a reducing agent such as ferrous chloride or ferrous sulphate. This forms a solidified mass which has excellent hardness and high temperature strength enabling it to be directly added to molten metal. Particles coated with hardened metal baghouse dust can be used in the Midrix process or can be used to add carbon to molten metal. This is an excellent way to dispose of waste metal baghouse dust.

Abstract: The present invention is directed to a process for recovering metal values from metal-bearing materials. During a reactive process, a seeding agent is introduced to provide a nucleation site for the crystallization and/or growth of solid species which otherwise tend to passivate the reactive process or otherwise encapsulate the metal value, thereby reducing the amount of desired metal values partially or completely encapsulated by such material. The seeding agent may be generated in a number of ways, including the recycling of residue or the introduction of foreign substances. Processes embodying aspects of the present invention may be beneficial for recovering a variety of metals such as copper, gold, silver, nickel, cobalt, molybdenum, zinc, rhenium, uranium, rare earth metals, and platinum group metals from any metal-bearing material, such as ores and concentrates.

Abstract: The method for producing a mother alloy for an iron-based amorphous alloy has the steps of (a) melting raw materials for elements constituting the amorphous alloy together with at least one oxide of an element constituting the amorphous alloy, the raw materials containing aluminum as an inevitable impurity, and the oxide having a smaller standard free energy of formation than that of Al2O3 in an absolute value; and (b) removing the resultant Al2O3 from the melt, thereby reducing the content of aluminum to 50 ppm or less in the melt.

Abstract: A system and process for recovering copper from a copper-containing ore, concentrate, or other copper-bearing material to produce high quality cathode copper from a leach solution without the use of copper solvent extraction techniques or apparatus. A process for recovering copper from a copper-containing ore generally includes the steps of providing a feed stream containing communicated copper-containing ore, concentrate, or other copper-bearing material, leaching the feed stream to yield a copper-containing solution, conditioning the copper-containing solution through one or more physical or chemical conditional steps, and electowinning copper directly from the copper-containing solution, without subjecting the copper-containing solution to solvent extraction.

Abstract: A molten metal vessel includes a first chamber for containing molten metal such as molten aluminum therein, a filtration chamber in which impurities contained in the molten metal are removed, and a second chamber for reserving clean molten metal to be supplied to a casting die. The molten metal flows from the first chamber to the second chamber through the filtration chamber. A pair of filters, preferably a pair of cylindrical filters, are disposed in the filtration chamber, so that the impurities contained in the molten metal can be filtered twice. The filters are attached to the bottom of the filtration chamber where molten metal oxides hardly develop, so that the filters are easily replaced with new ones for the maintenance purpose. A rod-shaped heater may be disposed in the cylindrical filters to keep the molten metal temperature in a strictly controlled range. Thus, the impurities are effectively removed from the molten metal through the filters which are easily replaceable.

Abstract: A method of recovering precious metals from metal alloys produced aluminothermically from base metal smelter slag, includes treating the metal alloy with aqueous sulphuric acid solution having a pH of not greater than about 2 to cause dissolution of nickel and/or cobalt and iron and to cause formation of hydrogen sulfide which reacts with copper in the metal alloy to form a copper sulfide precipitate containing at least one precious metal, and separating the copper sulphide precipitate containing at least one precious metal from the remaining solution containing cobalt sulphate and/or nickel sulphate and ferrous sulphate.

Abstract: In a method of operating a copper smelting furnace, wherein a ferrous substance containing more than 80 wt. % metallic iron having a specific gravity of 3.0-8.0 and particle diameter of 0.3-15 mm is added to copper smelting slag containing Fe having an oxidation-reduction number of 3+ and to the Fe3O4 in the intermediate layer, thereby deoxidizing the Fe3O4 to FeO, the method reduces the Fe3O4 within the slag layer and the Fe3O4 generated in the intermediate layer between the slag layer and the matte layer. So that their viscosity is reduced and separation rate is increased, thus increasing the yield rate of useful metal, and the problems that originate in the intermediate layer are eliminated.

Abstract: A blowing lance for treating molten metals which are situated in vacuum-treatment vessels, in particular steel in RH vessels, having a central pipe and an encasing pipe which is arranged coaxially with respect to the central pipe and can be cooled by a cooling medium. The central pipe and the encasing pipe are connected to supply lines, which in turn can be connected to an oxygen station, a fuel-gas station and an inert-gas station and to a solids-feed device. In this lance, the cooled encasing pipe is arranged at a distance from the central pipe over its entire length. The free annular area (AR) between the two pipes satisfying the following statement AR=0.8 to 1.2×AZ where AZ=free cross-sectional area of the central pipe. The end of the central pipe is designed in the form of a Laval nozzle. The nozzle opening of the central pipe is being arranged at a distance (a) inside the encasing tube, where a=0.5 to 0.8×d where d=clear diameter of the central pipe.

Abstract: A process for the recovery of copper from an aqueous phase containing nitrate ions, in which the aqueous phase is contacted with a solution of an oxime extractant in a water-immiscible organic solvent, which comprises using at least one of the following process variants: I) reducing the acidity of the aqueous phase prior to contact with the organic solution; and II) reducing the electromotive force in the aqueous phase prior to contact with the organic solution.

Abstract: A hydrometallurgical process for the recovery of nickel and cobalt values from a sulfidic flotation concentrate. The process involves forming a slurry of the sulfidic flotation concentrate in an acid solution, and subjecting the slurried flotation concentrate to a chlorine leach at atmospheric pressure followed by an oxidative pressure leach. After liquid-solids separation and purification of the concentrate resulting in the removal of copper and cobalt, the nickel-containing solution is directly treated by electrowinning to recover nickel cathode therefrom.

Abstract: The invention is concerned with techniques and apparatus suitable for extraction of at least one valuable metal such as one or more of: gold, platinum, silver, cobalt, nickel, molybdenum, and manganese from a starting material which, by way of example, could be freshly mined mixed ore containing both oxidic and refractory (sulphide) ores.

Abstract: A direct smelting process for producing molten iron and/or ferroalloys from a metalliferous feed material is disclosed. The process is a molten bath based process that is carried out in a direct smelting vessel. The process includes the steps of supplying metalliferous feed material, carbonaceous material and fluxes into the vessel; smelting metalliferous feed material to molten iron in the molten bath; and injecting an oxygen-containing gas into the vessel to post-combust gases generated in the process. The process is characterised by controlling the level of molten metal in the vessel by adjusting the pressure in the vessel.

Abstract: A method of producing a nickel base alloy includes casting the alloy within a casting mold and subsequently annealing and overaging the ingot at at least 1200° F. (649° C.) for at least 10 hours. The ingot is electroslag remeelted at a melt rate of at least 8 lbs/min (3.63 kg/mm.), and the ESR ingot is then transferred to a heating furnace within 4 hours of complete solidification and is subjected to a novel post-ESR heat treatment. A suitable VAR electrode is provided form the ESR ingot, and the electrode is vacuum arc remelted at a melt rate of 8 to 11 lbs/minute (3.63 to 5.00 kg/minute) to provide a VAR ingot. The method allows premium quality VAR ingots having diameters greater than 30 inches (762 mm) to be prepared from Alloy 718 and other nickel base superalloys subject to significant segregation on casting.

Abstract: A method of increasing the leaching yield of gold in the cyanide treatment of refractory ores or concentrates of such ores, while delivering air in an alkaline environment at atmospheric pressure, wherein gold present in said ores or concentrates is bound as tellurides. The method is characterised by carrying out the cyanide treatment at a temperature above room temperature, up to a temperature immediately beneath the boiling point of the leaching liquid. The treatment is suitably carried out at a temperature of 60-80° C., and at a pH between 10 and 12.

Abstract: A metallothermy method includes continuously withdrawing an ingot of a metal product such as uranium or a uranium alloy as it is formed from an oxide or salt of the metal. The method employs upper and lower communicating crucibles. The upper crucible contains a layer of reducing medium floating on a solvent medium. The metal oxide or metal salt is reduced as it is introduced into the layer reducing medium to form metal particles and slag. The settling metal is melted by further induction heating, collected in the lower crucible and withdrawn. The slag is absorbed by the solvent medium which is regenerated with the use of electrolysis.

Abstract: An improved process for successful and homogeneous incorporation of ruthenium and iridium into titanium and titanium alloy melts, ingots, and castings via traditional melting processes (e.g., VAR and cold-hearth) has been developed. This result is achieved through the use of low-melting point Ti-Ru or Ti—Ir binary master alloys within the general composition range of ≦45 wt. % Ru and with a preferred composition of Ti-(15-40 wt. % Ru), or within the general composition range of ≦61 wt. % Ir and with a preferred composition of TI-(20-58 wt. % Ir). Primary features are its lower melting point than pure titanium, lower density than pure Ru and Ir metals, and the ability to be readily processed into granular or powder forms.

Abstract: A method for producing high-purity niobium involves refining crude niobium in an electrolyte comprising a melt of salts containing a complex niobium and potassium fluoride and an equimolar mixture of alkaline metal chlorides, the electrolyte further containing sodium fluoride in the amount of from 5 to 15 wt %, and subjecting the obtained cathode deposit to electron-beam melting in a vacuum free of oil vapors under a residual gas pressure of from 5*10−5 to 5*10−7 mm Hg, a melting rate of from 0.7 to 2 mm/min and a leakage into a melting chamber from 0.05 to 0.005 l·&mgr;m/s to produce an ingot of niobium. The method produces high-purity niobium having the total amount of impurities within the range of from 0.002 to 0.007 wt % which satisfies the requirements imposed on the materials used in microwave technology and microelectronics, with reduced losses of niobium in both of the refining stages and increased yield of high-purity niobium.

Abstract: A smelting process wherein very pure iron or various iron family metals are economically obtained from ores which contain iron family metals by hydrometallurgy. The process involves: (a) grinding an ore containing iron family metals to pulverize the ore into fines of 25 mesh undersize; (b) immersing the pulverized ore into at least one inorganic acid having a concentration of 1N to 8N to elute the iron family metals into the inorganic acid to carry out a leaching; (c) filtering the resultant mixture of residue and inorganic acid containing eluted iron family metals to obtain a filtrate and a gangue; (d) adding an alkali to the filtrate obtained in step (c), whereby a hydroxide of the iron family metal is precipitated; (e) filtering the resultant suspension which contains the hydroxide to collect the hydroxide of iron family metals; and (f) heating the collected hydroxide or a dried hydroxide thereof in a reducing atmosphere at a temperature of 400 to 500° C.