Abstract: The invention relates to a method for the direct reduction of oxidic iron carrier particles to a reduction product in a fluidized bed through which a reduction gas containing 30-100 mol % hydrogen H2 flows in crossflow. At least 90% by mass of oxidic iron carrier particles introduced into the fluidized bed have a particle size of less than or equal to 200 micrometers. The superficial velocity U of the reduction gas flowing through the fluidized bed is set between 0.05 m/s and 1 m/s such that, for the particle size d equal to d30 of the oxidic iron carrier particles introduced into the fluidized bed, it is above the theoretical suspension velocity Ut and is less than or equal to Umax.
Type:
Grant
Filed:
March 12, 2020
Date of Patent:
June 27, 2023
Assignee:
Primetals Technologies Austria GmbH
Inventors:
Roland Eisl, Bernhard Hiebl, Hanspeter Ofner, Norbert Rein, Johann Wurm
Abstract: An apparatus and a process for the production of high purity silicon from silica containing material such as quartz or quartzite, using a vacuum electric arc furnace, are disclosed.
Abstract: A method for producing a high purity high carbon molten chrome product from chrome and carbon bearing material, said method comprising the steps of: (a) continuously introducing chrome compacts directly into an electric melter; (b) heating and melting the chrome compacts in the electric melter at a temperature of between about 1300° C. to about 1700° C. to form high carbon molten chrome; (c) preventing oxidation of the high carbon molten chrome via minimization of the ingress of oxygen containing gas in said heating step; (d) carburizing the high carbon molten chrome to form high carbon molten metallized chrome; (e) purifying the high carbon molten metallized chrome by reducing silicon oxides to silicon and desulfurizing the high carbon molten metallized chrome to produce the high purity high carbon molten chrome product; and (f) discharging the high purity high carbon molten chrome product from the electric melter.
Abstract: The invention describes a method for recovering molybdenum, nickel, cobalt or their mixtures from used or regenerated catalysts in an electric arc furnace containing a heel of liquid cast iron, surmounted with a fluid slag, comprising the following steps: a) adding used or regenerated catalysts into the heel contained in the electric arc furnace, b) adding dosed lime in order to obtain a slag with a CaO to Al2O3 ratio comprised between 0.7 and 1.3, c) mixing the heel by injecting gas so as to avoid formation of crusts, d) melting the used or regenerated catalysts in the electric arc furnace in order to obtain a liquid ferro-alloy.
Abstract: A method for the recovery of refractory debris materials and ladle slags as process slags in the iron metallurgy production in EAFs and the related metering to the furnace for the formation of the process slag comprises the following steps: grinding and screening of the refractory debris materials until powders of controlled granulometry are obtained, storage of the powders in storage sites, injection of the powders into an EAF furnace by means of automatic metering of the various components.
Abstract: This invention relates to a method and an apparatus for smelting titanium metal by the thermal reduction of titanium oxide (TiO2) to titanium metal (Ti); a mixed salt of calcium chloride (CaCl2) and calcium oxide (CaO) contained in a reaction vessel is heated to form a molten salt which constitutes a reaction region, the molten salt in the reaction region is electrolyzed thereby converting the molten salt into a strongly reducing molten salt containing monovalent calcium ions (Ca+) and/or calcium (Ca), titanium oxide is supplied to the strongly reducing molten salt and the titanium oxide is reduced and the resulting titanium metal is deoxidized by the monovalent calcium ions and/or calcium. The method and the apparatus make it feasible to produce commercially titanium metal suitable for a variety of applications from titanium oxide.
Abstract: A metal having a high chromium content, characterized in that it is produced in an arc melting furnace and contains Cr in an amount of 85% or more and has an Al content of 0.005% or less, an Si content of 0.1% or less and an S content of 0.002% or less; and a method for producing the metal having a high chromium content which comprises reducing a chromium oxide heated and melted in an arc melting furnace with Si, to thereby prepare a metal melt containing 85% or more of CR, discharging a slag formed by the reduction with Si from the arc melting furnace, adding a fresh basic flux into the arc melting furnace, melting the basic flux with arc, to bring a slag formed by the melting of the basic flux to contact with the above metal melt and thereby refine the metal melt, and then taking out the refined metal melt from the arc melting furnace, followed by casting.
Abstract: For effectively reprocessing iron-containing residual smelting plant materials (1 to 3), in which iron may be present both in metallic form and in oxidic form, with lowest possible energy expenditure, the residual smelting plant materials (1 to 3) are processed into agglomerates (8,11), the agglomerates (8,11) are charged into an electric arc furnace (10), melted there and reduced, and the resultant melt is refined (FIG. 1).
Type:
Grant
Filed:
December 20, 1999
Date of Patent:
April 16, 2002
Assignee:
Voest Alpine Industrieanlagenbau GmbH
Inventors:
Johann Lehner, Alexander Fleischanderl, Wilfried Pirklbauer, Stefan Dimitrov
Abstract: A method of introducing a denitrogenizing flux material into a container of molten metal includes steps of providing a wire-like vector that has an inner core of flux material and an outer layer that is used to contain the inner core, and using a wire feed machine to introduce the wire-like vector into a container of molten metal. In comparison with conventional top slag removal techniques, this process permits the material from which the inner core is made to be injected into the container of molten metal at a speed and direction that promotes a controlled mixing of the flux material and the molten metal.