In Shaft Furnace Or Multi-hearth Furnace Patents (Class 75/760)
  • Patent number: 9238253
    Abstract: A processed DRI material having an average surface roughness (Ra) of less than 1.5 ?m is disclosed. A method and system for making processed DRI are also disclosed. One embodiment of the method and system may include assembling a rotatable chamber having an internal screen capable of supporting DRI during tumbling, with at least one opening in the chamber to permit fines to exit the chamber during tumbling, and delivering DRI into the chamber to tumble the DRI on the screen to remove fines from the DRI. Another embodiment of the method and system may include assembling a rotatable chamber having a feed end and an exit end, and having a screen therein capable of supporting DRI as the DRI moves through the chamber, and delivering DRI to the chamber and rotating the chamber to tumble the DRI while removing fines.
    Type: Grant
    Filed: September 9, 2011
    Date of Patent: January 19, 2016
    Assignee: Nu-Iron Technology LLC
    Inventors: Gary M. Levanduski, Kyle Bartholomew, David W. Hendrickson, Christopher P. Manning, Anthony Ramjewan
  • Patent number: 7935174
    Abstract: The invention concerns a method for treating iron-and-steel plant sludge comprising adjusting the available CaO content of the sludge so as to obtain an available CaO content of 3% to 8% based on the sludge weight, adding a carbon-containing fuel, introducing the sludge onto one of the upper stages of a multistage furnace, heating the multistage furnace, gradually transferring the sludge onto the lower stages, and adjusting the temperature of the exhaust gases of the multistage furnace to at least 500.degree. C. and that of the treated sludge at the output of the multistage furnace to a temperature ranging between 700.degree. C. and 800.degree. C.
    Type: Grant
    Filed: October 4, 2005
    Date of Patent: May 3, 2011
    Assignee: Paul Wurth S.A.
    Inventors: Jean-Luc Roth, Emile Lonardi
  • Patent number: 6565623
    Abstract: The present invention refers to a method and an equipment for curing and drying self-reducing agglomerates containing cement as a binder in the presence of saturated vapor at a temperature from about 70 to about 110° C. and under atmospheric pressure. The treatment is performed in one single equipment.
    Type: Grant
    Filed: March 20, 2001
    Date of Patent: May 20, 2003
    Assignee: Startec Iron LLC
    Inventors: Marcos de Albuquerque Contrucci, Edmar Saul Marcheze
  • Patent number: 5925165
    Abstract: In a method for processing solid residues from refuse incineration plants the slag is melted and heavy metals from the melt (16) are separated for reutilization. The slag is directly transferred from the refuse incineration plant into a first heating chamber (2) and melted there under oxidizing conditions. The melt (16) produced therefrom is transferred to a second heating chamber (3), in which the heavy metal compounds are reduced to their metallic form. Furthermore, additional finely divided residues, such as fly ash, boiler ash and filter dust, are introduced into the second heating chamber (3) via a hollow graphite electrode (19). The melt (16) is then passed on to a third heating chamber (4), in which the residual readily volatile metals are vaporized and the residual non-volatile metals are sedimented. The essentially heavy-metal-free melt is then cooled to form vitreous granules.
    Type: Grant
    Filed: May 22, 1996
    Date of Patent: July 20, 1999
    Assignees: Von Roll Umwelttechnik AG, Holderbank Financiere Glarus AG
    Inventors: Karl Heinz Pflugl, Norbert Kiethe, Ernst Hugentobler, Hans Ruegg, Ruedi Frey, Anton Mayer, Theo Rey, Alfred Edlinger
  • Patent number: 5897674
    Abstract: A method for manufacturing coal agglomerates for use in a direct smelting reducing furnace is disclosed, in which a fine coal is agglomerated at a high temperature in a simple manner, or anthracite or low free swelling coal having a low free swelling index is mixed with the fine coal, and the mixture is agglomerated at a high temperature, thereby turning the low quality coal to useful purpose. The present invention is characterized in that a fine coal having a free swelling index of 3.0 or more and a particle size of 8 mm or less, or the fine coal mixed with 70 weight % of anthracite or a low free swelling coal, is maintained at 600.degree. C. or over for 5 minutes or more, thereby manufacturing coal agglomerates for use in a direct smelting reducing furnace.
    Type: Grant
    Filed: August 28, 1997
    Date of Patent: April 27, 1999
    Assignees: Pohang Iron & Steel Co., Ltd., Research Institute of Industrial Science & Technology, Voest-Alpine Industrieanlagenbau
    Inventors: Young Chae Jung, Dal Hoi Lee, Min Young Cho