Abstract:  The process flow of preferential floating copper-magnetite and pyrrhotite recovery by magnetic separation from copper tailings-pyrite recovery by flotation from magnetic separation tailings was adopted in a copper mine on-site process in Anhui. Flotation operation all used flotation machines in the mine. When the grade of raw ore is reduced， the copper grade of concentrate is difficult to reach the design index. In order to improve the grade of copper concentrate， on the basis of laboratory tests， CCF flotation column and cyclone-static microbubble flotation column were used for semi-industrial tests. The test results show that the concentrate grade of the flotation column is higher than that of the on-site concentrate in the same period. The concentrate grade of the CCF flotation column is up to 21.01%， which is 2.9 percentage points higher than that of the production index in the same period. The concentrate grade of the cyclone-static microbubble flotation column is 19.96%， which is 1.05 percentage points higher than that of the production index in the same period. It indicates that CCF type flotation column is more suitable for the treatment of the ore.

Key words:  Copper ore, Flotation, CCF flotation column, Cyclone-static micro-bubble flotation column, Pilot test