Apparatus for producing reduced iron

Abstract

In the production of reduced iron by agglomerating a mixed powder of an iron material and a reducing agent to form compacts like briquettes or pellets, and reducing the compacts in a high temperature atmosphere, when the temperature of reduced compacts is 900° C. or higher, the oxide content in the reduced compacts is set at 11 % or more, and the basicity of the reduced compacts is set at 0.5 or higher.

1 . An apparatus for producing reduced iron by agglomerating a mixed powder of an iron material and a reducing agent to form compacts like briquettes or pellets, and reducing the compacts in a high temperature atmosphere, further including: 
 grinding means for grinding reduced compacts.    
     
     
         2 . The apparatus for producing reduced iron as claimed in    claim 1   , wherein: 
 the grinding means is disposed in a discharge port of an RHF, and the reduced compacts ground by the grinding means are accommodated and stored in a reservoir.    
     
     
         3 . The apparatus for producing reduced iron as claimed in    claim 1   , wherein: 
 sifting means is provided for sifting the reduced compacts according to size of the compact, and large lumps of the reduced compacts sifted out by the sifting means are ground by the grinding means.    
     
     
         4 . The apparatus for producing reduced iron as claimed in    claim 3   , wherein: 
 the sifting means is composed of a plurality of sieves, and a vibrator for vibrating the sieves, each of the sieves being composed of a plurality of rods supported at predetermined intervals and in an inclined state on an upper portion of a body.    
     
     
         5 . The apparatus for producing reduced iron as claimed in    claim 3   , wherein: 
 reduced compacts discharged from an RHF are sifted by the sifting means, then large lumps of the reduced compacts are ground by the grinding means, and small lumps of the reduced compacts sifted out by the sifting means and small lumps of the reduced compacts formed by grinding by the grinding means are accommodated and stored in a reservoir.    
     
     
         6 . The apparatus for producing reduced iron as claimed in    claim 3   , wherein: 
 temporary storage means is provided for temporarily storing the large lumps of the reduced compacts sifted out by the sifting means, and after a predetermined amount or a larger amount of the large lumps of the reduced compacts are stored in the temporary storage means, all of these large lumps are ground by the grinding means.    
     
     
         7 . The apparatus for producing reduced iron as claimed in    claim 1   , wherein: 
 a reservoir for accommodating and storing the reduced compacts is provided in a discharge port of an RHF, the grinding means is disposed in a charge port for a raw material tank in a melting furnace, and immediately before the reduced compacts in the reservoir are charged into the raw material tank, large lumps of the reduced compacts are ground by the grinding means.    
     
     
         8 . The apparatus for producing reduced iron as claimed in    claim 7   , wherein: 
 sifting means for sifting the reduced compacts according to size of the compact is provided in the charge port for the raw material tank in the melting furnace, and large lumps of the reduced compacts sifted out by the sifting means are ground by the grinding means and then charged into the raw material tank.