METHOD OF CONCENTRATION OF RARE-EARTH ORES Russian patent published in 2002 - IPC

FIELD: concentration of minerals; production of rare-earth rough concentrates at mining industry enterprises. SUBSTANCE: starting rare-earth ore is ground and is subjected to first stage of magnetic separation including several procedures, thus obtaining heavy magnetic product, medium magnetic middlings and nonmagnetic product. Heavy magnetic product and medium magnetic middlings of first stage of magnetic separation are subjected to classification, thus obtaining coarse and fine products. Fine product is directed for additional magnetic separation including several procedures, thus obtaining heavy magnetic product, medium magnetic middlings and nonmagnetic product. Coarse classification product is directed to second stage of grinding followed by directing the ground product for additional magnetic separation. Nonmagnetic product of first stage of magnetic separation is subjected to additional grinding and is directed to second stage of magnetic separation, thus obtaining weak magnetic product and tailings. Nonmagnetic product of additional magnetic separation is directed to last procedure of first magnetic stage of separation. Weak magnetic product of first stage of magnetic separation is combined with weak magnetic product of second stage of magnetic separation in rough rare-earth concentrate. Last procedure of first stage of magnetic separation is performed at induction of magnetic field of 1.4-1.5 and second stage of magnetic separation at 1.5-2.0 T. EFFECT: reduced losses of rare-earth components. 2 cl, 1 dwg, 3 tbl