METHOD OF EXTRACTION OF DIAMOND FROM DIAMOND- CONTAINING RAW MATERIAL Russian patent published in 2003 - IPC

FIELD: concentration of minerals; concentration of diamond-containing ores; processing kimberlite ores. SUBSTANCE: proposed method includes grinding of starting diamondcontaining raw material, classification of ground raw material by size classes, initial concentration of classified raw material, grinding after concentration of classified raw material of middlings thus obtained followed by concentration, grinding and final processing. Said operations are performed on dry raw material at negative or positive temperatures. Starting diamond- containing raw material at size of 0-100 mm is directed to at least two processing stages; each stage includes classification of raw material into three classes: coarse, medium and fine containing mass of crystals at size of 15 mm which is directed to final processing section. Open crystals are extracted from coarse class by X- ray fluorescent apparatus. Then, middlings are ground on con-shaped static vibratory grinder. Ground middlings thus obtained are combined with medium class and directed to next stage for processing. After obtaining middlings of 15 mm in size at last stage, thy are directed to final processing section and middlings of fine class obtained at previous stages are combined with them. Common air separation of these middlings is performed in final processing section separating coarse fraction, sands and dust-like fraction. Coarse fraction is directed after air separation for final processing at two stages; each stage includes grinding by abrading in drum-type vibration grinder followed by separation of coarse fraction, sands and dust-like fraction in air separator. Then, coarse fraction is directed to next final processing stage; sands are directed for electric separation or foam flotation and dust-like fraction is directed to tailing pond. Upon completion of final processing stage, remaining coarse fraction is directed after last air separation for extraction of diamonds in X-ray fluorescent apparatus or adhesive apparatus or electric separator. EFFECT: completeness of extraction; enhanced efficiency. 2 cl, 1 dwg