Method of and apparatus for manufacturing the metallic iron

Abstract

A method of manufacturing reduced iron at high Fe purity efficiently with less intrusion of a slag components using less carbonaceous reducing agent and fuel, comprising charging a compact of the iron oxide containing a carbonaceous reducing agent in a packed bed, reducing the iron oxide to 90% or more while keeping in a solid state by a heat source formed from the lower portion of the furnace and then melting the same, as well as an apparatus for manufacturing the metallic iron, comprising a fire grate disposed in the inside of a packed bed, a compact charged layer on the fire grate, a charging product charging mechanism for supplying the compact and a mechanism for discharging an exhaust gas in the furnace, and a fuel charging mechanism, a fuel combustion space and a molten product stores bath disposed below the fire grate.

What is claimed is:  
     
         1 . A manufacturing method by reducing a starting material comprising at least a carbonaceous reducing agent and an iron oxide containing material wherein the method comprises charging the starting material into a packed bed, burning a fuel in a lower portion of the packed bed to heat a compact disposed in an upper portion thereof by the heat of combustion formed, heating and reducing the metallic iron in the iron oxide containing material and then melting the same.  
     
     
         2 . A manufacturing method as defined in  claim 1 , wherein the iron oxide in the iron oxide containing material is heated and reduced to 90% of reduction degree or more and then melted.  
     
     
         3 . A manufacturing method as defined in  claim 1 , wherein a carbonaceous reducing agent is incorporated by more than the stoichiometric amount for reducing reaction in the compact and then charged in the packed bed.  
     
     
         4 . A manufacturing method as defined in  claim 1 , wherein the concentration of the carbonaceous reducing agent on the surface of the compact is increased and then the compact is charged into the packed bed.  
     
     
         5 . A manufacturing method as defined in  claim 1 , wherein a carbon source is covered on the surface of the compact and then the compact is charged into the packed bed.  
     
     
         6 . A manufacturing method as defined in  claim 1 , wherein a material inert to an oxidative gas is present on the surface of the compact.  
     
     
         7 . A manufacturing method as defined in  claim 1 , wherein a flux is incorporated into the compact to control the melting temperature of a slag formed upon heating and reducing or melting.  
     
     
         8 . A manufacturing method as defined in  claim 1 , wherein a furnace provided at the inside thereof with a fire grate is used as the packed bed and the compact is charged on the fire grate and a fuel is burnt below the fire grate.  
     
     
         9 . A manufacturing method as defined in  claim 8 , wherein a bed layer having open cells is disposed on the fire grate.  
     
     
         10 . A manufacturing method as defined in  claim 9 , wherein the bed layer comprises a lumpy carbon material layer.  
     
     
         11 . A manufacturing method as defined in  claim 9 , wherein the bed layer comprises a refractory layer.  
     
     
         12 . A manufacturing method as defined in  claim 8 , wherein at least one gas supply port is disposed above the fire grate along the direction of the height of the packed bed and an oxygen-containing gas is supplied through the gas supply port.  
     
     
         13 . A manufacturing method as defined in  claim 12 , wherein the gas formed upon heating and reduction of the compact is burnt by the supply of the oxygen-containing gas.  
     
     
         14 . A manufacturing method as defined in  claim 12 , wherein an auxiliary fuel is mixed with the oxygen-containing gas.  
     
     
         15 . A manufacturing method as defined in  claim 8 , wherein an auxiliary fuel is supplied toward the space below the fire grate.  
     
     
         16 . A manufacturing method as defined in  claim 15 , wherein the auxiliary fuel is a carbon-containing material.  
     
     
         17 . A manufacturing method as defined in  claim 1 , wherein the metallic iron, metallic manganese, metallic nickel, metallic chromium or an alloy thereof is manufactured by using a compact in which the starting material is substituted with one or more of the iron oxide, manganese oxide, nickel oxide and chromium oxide.  
     
     
         18 . An apparatus for manufacturing the metallic iron comprising a packed bed having a grate in the inside thereof, a charging portion for a compact comprising at least a carbonaceous reducing agent and an iron oxide containing material, a compact charging mechanism and a mechanism for discharging an exhaust gas in the furnace disposed above the fire grate, and a fuel combustion space and a molten product store space below the fire grate.  
     
     
         19 . A manufacturing apparatus as defined in  claim 18 , wherein a fuel supply port is disposed toward the fuel combustion space and a molten product discharge port is disposed to the molten product store space.  
     
     
         20 . A manufacturing apparatus as defined in  claim 18 , wherein a bed layer having open cells is provided on the fire grate.  
     
     
         21 . A manufacturing apparatus as defined in  claim 18 , wherein an upper combustion space for burning a gas formed from the compact is disposed above the fire grate.  
     
     
         22 . A manufacturing apparatus as defined in  claim 19 , wherein an oxygen-containing gas supply port is disposed toward the upper combustion space.  
     
     
         23 . A manufacturing apparatus as defined in  claim 20 , wherein a bed material charging mechanism is disposed toward the bed layer.  
     
     
         24 . A manufacturing apparatus as defined in  claim 19 , wherein a carbon material injection device is disposed toward the molten store space.