Treating Material In Rotary Kiln Patents (Class 75/662)
  • Patent number: 8636825
    Abstract: One aspect relates to a method for producing an alloy characterized by grinding tantalum to form a tantalum powder and grinding tungsten to form a tungsten powder; mixing the tantalum powder and the tungsten powder to form a blended powder. The weight fraction of tungsten powder in the blended powder is larger than in the desired alloy. A blended body is produced from the blended powder by a powder metallurgical route. A pre-alloy is produced by a first melting of the blended body and at least a fraction of at least one further metal by a melt metallurgical route. The alloy is produced by a second melting of the pre-alloy and the remaining fraction of at least one metal by a melt metallurgical route.
    Type: Grant
    Filed: April 21, 2011
    Date of Patent: January 28, 2014
    Assignee: W. C. Heraeus GmbH
    Inventors: Herwig Schiefer, Christoph Vogt, Heiko Specht, Jens Troetzschel, Egbert Stiedl
  • Patent number: 6494933
    Abstract: The invention relates to a method of utilizing secondary raw materials containing iron, zinc and lead, preferably steelmaking dusts, in a rotary tubular furnace customarily equipped for the rolling process, with basically adjusted rolling slag. By reducing the portion of the carbon carriers in the burden, the energy balance of the rolling process is improved on one hand, and the throughput of the rotary tubular furnace used is increased on the other hand. By improving the quality of the rolling slag, the capability of utilizing the same is favored.
    Type: Grant
    Filed: September 28, 2000
    Date of Patent: December 17, 2002
    Assignees: B. U. S. Zinkrecycling Freiberg GmbH, FNE Forschungsinstitut fur Nichteisen-Metalle
    Inventors: Eberhard Saage, Uwe Hasche, Wolfgang Dittrich, Diethart Langbein
  • Patent number: 6270551
    Abstract: A process for recovering iron from iron-bearing materials including steel mill waste and iron-bearing ores. The process includes the steps of providing a mixture of iron-bearing materials having iron oxides therein and carbonaceous material. Blending with the mixture an organic binder. The mixture is then agglomerated to form green compacts. The green compacts are then loaded into a preheated rotary hearth furnace void of compacts to form a layer of compacts no more than about two compacts high. The green compacts are heated for about 5-12 minutes at a temperature of between about 2200-2500° F. to reduce the compacts and evolve undesirable oxides from the compacts. The reduced compacts are then discharged from the rotary hearth furnace whereupon they are soaked to provide additional time for reaction to achieve 99% or more reduction of the iron oxides. The metallized iron compacts may then be cooled or transported hot to a steel making operation.
    Type: Grant
    Filed: July 27, 1998
    Date of Patent: August 7, 2001
    Assignee: Maumee Research & Engineering, Inc.
    Inventors: Franklin G. Rinker, Deane A. Horne, James A. Thornton, Valdis R. Daiga
  • Patent number: 5198020
    Abstract: Disclosed is a process of removing zinc from a phosphating process sludge wherein the phosphating process sludge is mixed with an additive adapted to form slaglike compounds of iron, calcium and/or barium with the phosphorus component of the phosphating process sludges. The mixture is reacted at temperatures of at least 800.degree. C. under reducing conditions. A previous agglomeration, particularly pelletizing, of the mixture will be of advantage. For a formation of iron compounds it will be particularly desirable to employ reaction temperatures of at least 900.degree. C., preferably of at least 1000.degree. C. and most preferably of at least 1100.degree. C. Metallurgical dusts are particularly suitable additives. For a formation of iron compounds it will be desirable to select a Fe:P molar ratio of at least 1.0 in case of a reaction temperature of .ltoreq.950.degree. C., of at least 1.5 in case of a reaction temperature of 950.degree. to 1050.degree. C., and of at least 2.
    Type: Grant
    Filed: January 8, 1992
    Date of Patent: March 30, 1993
    Assignee: Metallgesellschaft Aktiengesellschaft
    Inventors: Wolfgang Fennemann, Rolf Kola, Dieter Jentsch