METHOD OF CONCENTRATING MAGNETITE ORES Russian patent published in 1999 - IPC

FIELD: mining industry. SUBSTANCE: method is applicable in concentration of finely imbedded magnetite ores and consists in the following. Treatment of primarily ground crude concentrate is effected through preliminary magnetic deslurring, where fine product is removed as tail and coarse product is subjected to preliminary magnetic deslurring. Magnetic deslurring of secondary-grinding product of crude concentrate is carried out in two steps. Sizing of concentrate is performed when content of solids in hydrocyclone drain is 6.0-8.5%. Hydrocyclone sands, prior to be returned into the secondary crude concentrate grinding stage, are classified according to specified fineness class, coarse product being subjected to control classification. Fine products of hydrocyclone sand classification and control classification are subjected to magnetic concentration. The latter operation is carried out in two steps, the second-step concentration drain is returned into the head of process. EFFECT: improved quality of concentrate, increased degree of isolation of iron into concentrate, lowered specific surface of concentrate to optimum value, reduced specific consumption of materials by 30%, and reduced level of limiting impurities (lead pentaoxide, sulfur, silica) in concentrate. 3 dwg, 3 tbl