DESCRIPTION: A Unit Flash Flotation Cell in coarse concentration flotation circuit. This flowsheet is similar to our Coarse gravity concentration followed by flotation circuit.
ORE TREATED: This flowsheet can be used on ores wherein the base metal minerals are freed at a coarse size. This is often seen on Pb Lead/Galena flotation located on the ball mill discharge, in the center of the grinding circuit.
ADVANTAGES: The operation of the concentrating-table is inefficient due to the high tonnage of unclassified feed. The Unit Flotation Cell recovers the fines lost by the table as well as the coarse mineral.
The improved recoveries are particularly noticeable on gold or silver ores that are partially oxidized and decomposed. The minerals break finer in the grinding’ mill and are not recovered on the table. Flaky metallic gold is carried across the table with the tailing but may be floated in the Unit Flotation Cell because of the large mineral surface exposed and the high specific gravity pulp which promotes coarse flotation. The value of the classifier overflow is reduced to a uniformly low grade as surges from higher grade ore are smoothed out by the high recovery being made in the fine grinding circuit.
PROCESSING COMMENTS: In gold and silver ores the concentrates produced by the Flash Flotation Cell and by the table are generally high in grade and account for a major portion of the recovery of these metals. The concentrating tables used in these circuits are rapidly being replaced by the more efficient and economical Mineral Jig.