Method for producing titanium oxide containing slag

Abstract

The present invention provides a method for efficiently manufacturing a titanium oxide-containing slag from a material including titanium oxide and iron oxide, wherein a reduction of titanium dioxide is suppressed and the electric power consumption is minimized. The method includes the steps of: heating a raw material mixture including titanium oxide, iron oxide, and a carbonaceous reductant, or the raw material mixture further including a calcium oxide source, in a reducing furnace; reducing the iron oxide in the mixture to form reduced iron; feeding the resultant mixture to a heating melting furnace; heating the resultant mixture in the heating melting furnace to melt the reduced iron and separate the reduced iron from a titanium oxide-containing slag; and discharging and recovering the titanium oxide-containing slag out of the furnace.

1 . A method for manufacturing a titanium oxide-containing slag, comprising the steps of: 
 (A) heating a raw material mixture including titanium oxide, iron oxide, and a carbonaceous reductant in a reducing furnace;    (B) reducing the iron oxide in the mixture to form reduced iron;    (C) feeding the resultant mixture to a heating melting furnace;    (D) heating the resultant mixture in the heating melting furnace to melt the reduced iron and separate the reduced iron from a titanium oxide-containing slag; and    (E) discharging and recovering the titanium oxide-containing slag out of the furnace.    
     
     
         2 . The method according to  claim 1 , wherein, in step (C), the resultant mixture is fed to the heating melting furnace without substantial cooling.  
     
     
         3 . The method according to  claim 1 , wherein the reducing furnace is a rotary hearth furnace.  
     
     
         4 . The method according to  claim 1 , wherein the raw material mixture is an agglomerated compact.  
     
     
         5 . The method according to  claim 1 , wherein the raw material mixture further comprises a calcium oxide source.  
     
     
         6 . A method for manufacturing a titanium oxide-containing slag, comprising the steps of: 
 (A) heating a raw material mixture including titanium oxide, iron oxide, and carbonaceous reductant in a reducing-melting furnace;    (B) reducing the iron oxide in the mixture to form reduced iron;    (c) further heating the resultant mixture to melt the reduced iron and separate the reduced iron from a titanium oxide-containing slag; and    (D) discharging and recovering the titanium oxide-containing slag out of the furnace,    wherein the reducing-melting furnace is a moving hearth reducing-melting furnace.    
     
     
         7 . The method according to  claim 6 , wherein the moving hearth reducing-melting furnace is a rotary hearth furnace.  
     
     
         8 . The method according to  claim 6 , 
 wherein the reducing-melting furnace has at least two sections in a moving direction of the hearth; one of the section being upstream of the hearth in the moving direction is a reduction section, the other section being downstream of the hearth in the moving direction is a heating melting section; and    the temperature of each section is separately controlled.    
     
     
         9 . The method according to  claim 8 , 
 wherein the temperature of the reduction section is in the range of 1200° C. to 1500° C.;    the temperature of the heating melting section is in the range of 1300° C. to 1500° C.; and    the temperature of the heating melting section is 100° C. to 300° C. higher than that of the reduction section.    
     
     
         10 . The method according to  claim 6 , wherein the raw material mixture is an agglomerated compact.  
     
     
         11 . The method according to  claim 6 , wherein the raw material mixture further comprises a calcium oxide source.