METHOD OF GRAVITY-WASHING SEPARATION OF COALS Russian patent published in 2025 - IPC B03B7/00 B03B5/30 

FIELD: performing operations.

SUBSTANCE: proposed invention relates to dressing of minerals used in preparation of power-generating solid fuel for combustion and can be used for separation of brown and bituminous coals at early stage of coalification using highly mineralized water sources of natural origin in order to obtain coal concentrate with low ash content and sulphur content and high combustion heat. Method of gravity-washing separation of coals includes crushing of initial coal and its screening, subsequent heavy-medium separation with production of concentrated coal and dressing wastes, their washing, mixing and drying. Crushing and screening is performed to produce coal with size of 0-3.25 mm. Heavy-medium separation with obtaining concentrate of enriched coal and dressing wastes is carried out in solution of natural underground chloride sodium brine with density of 1160-1175 kg/m³ or solution of water of surface highly mineralized lakes with density of 1160-1210 kg/m³. Concentrate of enriched coal and enrichment wastes are washed separately with total mineralization of not more than 1000 mg/dm³, then, excess flushing water, concentrated coal and dressing wastes are mixed. Drying of the obtained mixture is carried out in a drying pipe with a drying agent with an inlet temperature of 700-750 °C and with outlet temperature of 90-100 °C.

EFFECT: increasing the efficiency of gravity enrichment by increasing the amount of enriched coal concentrate obtained by separating valuable rock from enrichment waste.

1 cl, 1 dwg, 4 tbl