GRAVITY METHOD OF REMOVING HIGH-ASH SLIME FROM COAL DRESSING MUDDY WATER CIRCUIT Russian patent published in 2010 - IPC B03B7/00 

FIELD: process engineering.

SUBSTANCE: invention relates to muddy water processes in dressing and can be used in mixing, dressing and other industrial branches. Proposed method comprises dry grading to particle size on screen, wetting coal by water with simultaneous forced mixing, wet grading on screen without adding water with liberation of mesh plus and mesh minus of 1-0 mm-particle size, dewatering of mesh minus on belt-type vacuum filter, returning pure water in circulation circuit and directing high-ash slime into dump. Amount selected proceeding from ratio of (30-40):1 is used in forced mixing. after dry grading and prior to dewatering, mesh minus is directed to cyclone thickening performed to slime solid content in thickened product of at least 35%. Drained product is directed to plate-type thickener. Thickened product is dewatered at belt-type vacuum filter to produce filtrate to be directed, together with plate-type thickener product, into slime basin. Drained product of said basin is directed to thickening in gravity stepped thickener to produce resultant slime with content of soli in thickened product of at least 65% and ash content of 58-62%.

EFFECT: higher efficiency, reduced effects on environmental conditions.

1 dwg