Method for improving the reduction degree in the smelting of ferroalloy

Abstract

The invention relates to a method for improving the reduction degree of metal components in a chromite concentrate when smelting ferroalloy suitable for manufacturing of stainless steel. The chromite concentrate is fed together with nickel-containing raw material so that by means the amount of nickel-containing raw material it is achieved a desired reduction degree for the metal components of ferroalloy.

1 . Method for improving the reduction degree of metal components in a chromite concentrate when smelting ferroalloy suitable for manufacturing of stainless steel, characterized in that the chromite concentrate is fed together with nickel-containing raw material so that by means the amount of nickel-containing raw material it is achieved a desired reduction degree for the metal components of ferroalloy. 
     
     
         2 . Method according to the  claim 1 , characterized in that the nickel-containing raw material is fed 5-25 weight %, advantageously 10-20 weight % of the total amount of the material to be fed into the smelting furnace. 
     
     
         3 . Method according to  claim 1 , characterized in that during the smelting it is reduced at least 2.6% of chromium containing in the chromite concentrate. 
     
     
         4 . Method according to  claim 1 , characterized in that during the smelting it is reduced at least 37.4% of iron containing in the chromite concentrate. 
     
     
         5 . Method according to  claim 1 , characterized in that at least one part of the nickel-containing raw material is fed into the smelting furnace within pellets produced from the chromite concentrate. 
     
     
         6 . Method according to  claim 1 , characterized in that at least one part of the nickel-containing raw material is pretreated separately from the chrome concentrate pellets before feeding into the smelting furnace. 
     
     
         7 . Method according to  claim 1 , characterized in that it is fed into the smelting furnace as the nickel-containing raw material at least partly nickel oxide. 
     
     
         8 . Method according to  claim 1 , characterized in that it is fed into the smelting furnace as the nickel-containing raw material at least partly nickel ore and/or nickel concentrate. 
     
     
         9 . Method according to  claim 1 , characterized in that it is fed into the smelting furnace as the nickel-containing raw material at least partly a nickel-containing intermediate product achieved by the leaching and/or by precipitating of nickel ores and/or nickel concentrates. 
     
     
         10 . Method according to the  claim 9 , characterized in that it is fed into the smelting furnace at least partly nickel-containing intermediate product achieved by pressure leaching of lateritic or sulphidic nickel ores or nickel concentrates. 
     
     
         11 . Method according to the  claim 9 , characterized in that it is fed into the smelting furnace at least partly nickel-containing intermediate product achieved by atmospheric leaching of lateritic or sulphidic nickel ores or nickel concentrates. 
     
     
         12 . Method according to the  claim 9 , characterized in that it is fed into the smelting furnace at least partly nickel-containing intermediate product achieved by heap leaching of lateritic or sulphidic nickel ores or nickel concentrates. 
     
     
         13 . Method according to the  claim 9 , characterized in that it is fed into the smelting furnace at least partly nickel-containing precipitated product of nickel-containing solvent extraction solutions. 
     
     
         14 . Method according to the  claim 9 , characterized in that it is fed into the smelting furnace at least partly nickel-containing precipitated product of nickel-containing stripping solutions. 
     
     
         15 . Method according to the  claim 9 , characterized in that it is fed into the smelting furnace at least partly nickel-containing precipitated product of nickel-containing refining solutions. 
     
     
         16 . Method according to  claim 1 , characterized in that it is fed into the smelting furnace as nickel-containing material partly nickel concentrate, partly a nickel-containing intermediate product achieved by the leaching and/or by precipitating of nickel ores and/or nickel concentrates.