METHOD TO EXTRACT METALS FROM MILL TAILINGS Russian patent published in 2012 - IPC C22B7/00 C22B3/04 

FIELD: metallurgy.

SUBSTANCE: method includes joint leaching and activation of raw materials in a cage mill with extraction of metals into a solution simultaneously with crystal damage. After leaching and activation in a cage mill the material is laid into stacks, piles or trenches, treated with a solution of sulphuric acid. After treatment with a solution of sulphuric acid the material is washed with water, afterwards leaching is carried out with solutions of reagents. At the same time treatment of the material in stacks, piles or trenches is carried out with a solution of sulphuric acid with concentration of 10-30 g/l. Leaching of the material in stacks, piles or trenches is carried out with a solution of a sodium sulfide trioxosulfate with concentration of 10-20 g/l.

EFFECT: higher efficiency of metals extraction from mill tailings due to additional chemical treatment of mechanically chemically activated structural components of extracted materials after their extraction in a cage mill.

3 cl, 4 tbl, 1 ex