METHOD OF GRADING PARTICLES TO DENSITY BY HEAVY MEDIUM IN CENTRIFUGAL FIELD Russian patent published in 2012 - IPC B03B5/30 

FIELD: process engineering.

SUBSTANCE: invention relates to separation of solid materials with the help of heavy fluid in centrifugal field to be sued in mining, dressing, chemical industry etc, for extraction of noble metals from mineral stock. Proposed method comprises feeding the mix of different-density particles into heavy fluid located in centrifugal force field, splitting said particles over the heavy fluid layer depth, and discharging their therefrom. Heavy fluid surface is pre-coated by water layer. Particle to be separated are minced to fine state, wetted with water and fed into water layer in contact with heavy fluid. Solutions of water-insoluble organic compounds, for example, formyl tribromide, are used as heavy fluid. Heavy fluid in centrifugal field is rotated at 100-900 rpm

EFFECT: higher efficiency and yield, lower toxicity.

3 cl, 1 tbl