Patents Examined by Kaj K Olson
  • Patent number: 8753422
    Abstract: A method is disclosed for producing cast iron or semi steel with reducing gas in a high pressure refractory lined shaft furnace using minimal or no coke Iron ore and slag are fed into the operative top zone of the shaft furnace while reducing gas which is generated in a refractory lined gasifier using preheated oxygen is fed through tuyeres at the operative bottom and middle zones. The shaft furnace is operated at a high pressure to increase productivity and to facilitate use of the spent reducing gas downstream. Excess oxygen is fed into the shaft furnace to reduce the carbon content in the molten iron and generate semi steel. The size of the furnace is reduced. The method is economical.
    Type: Grant
    Filed: December 9, 2011
    Date of Patent: June 17, 2014
    Inventor: Keki Hormusji Gharda