Method for refining concentrate containing precious metals

Abstract

The invention relates to a method for refining precious metal concentrate, and according to said method, at least the precious metal concentrate ( 9 ), reaction gas ( 10 ), flux ( 11 ) and flue dust ( 12 ) to be treated are fed together into the reacton shaft ( 3 ) of a suspension smelting furnace ( 1 ); in the suspension smelting furnace, there are created separate phases, matte ( 8 ) and slag ( 7 ); and the slag created in the suspension smelting furnace is conducted into an electric furnace ( 2 ), so that there is created metallicized matte ( 14 ) and waste slag ( 13 ). Thereafter the matte ( 8 ) from the suspension smelting furnace is conducted to hydrometallurgical treatment ( 15 ), and the slag conducted into the electric furnace is treated together with a reducing agent and possibly with a material lowering the melting point or improving fluidity, and the obtained metallicized matte ( 14 ) is conducted either to hydrometallurgical treatment ( 16 ) or back into the suspension smelting furnace in ( 1 ).

1 . A method for refining precious metal concentrate, comprising: 
 a) feeding at least precious metal concentrate, reaction gas, flux and flue dust to be treated together into the reaction shaft of a suspension smelting furnace;    b) creating in the suspension smelting furnace, separate phases of matte and slag;    c) conducting the slag created in the suspension smelting furnace into an electric furnace, so that metallicized matte and waste slag is created    d) conducting the matte from the suspension smelting furnace to hydrometallurgical treatment, and    e) treating the slag conducted into the electric furnace together with a reducing agent and possibly together with a material lowering the melting point or improving the fluidity, and conducting the created metallicized matte either to hydrometallurgical treatment or back into the suspension smelting furnace.    
   
   
       2 . A method according to  claim 1 , further comprising replacing part of the precious metal concentrate to be fed into the suspension smelting furnace with sulfide concentrate.  
   
   
       3 . A method according to  claim 1  further comprising granulating the matte from the suspension smelting furnace and the metallicized matte from the electric furnace before the hydrometallurgical treatment.  
   
   
       4 . A method according to  claim 1 , further comprising treating the matte from the suspension smelting furnace and the metallicized matte from the electric furnace in the same hydrometallurgical process.  
   
   
       5 . A method according to  claim 1 , further comprising treating the matte from the suspension smelting furnace and the metallicized matte from the electric furnace in separate hydrometallurgical processes.  
   
   
       6 . A method according to  claim 1 , further comprising leaching in the hydrometallurgical treatment, the matte from the suspension smelting furnace in at least one step.  
   
   
       7 . A method according to  claim 1 , further comprising leaching in the hydrometallurgical treatment, the metallicized matte from the electric furnace in at least one step.  
   
   
       8 . A method according to  claim 6  further comprising carrying out the leaching in sulfate atmosphere.  
   
   
       9 . A method according to  claim 6  further comprising carrying out the leaching in a chloride atmosphere.  
   
   
       10 . A method according to  claim 6 , further comprising recovering the precious metals are from the leach residue.  
   
   
       11 . A method according to  claim 1 , further comprising conducting the ferrous precipitate created in the hydrometallurgical treatment of matte and metallicized matte into a suspension smelting furnace.