Iron ore dressing practice (1)

The mineral composition of the Qidashan iron ore in Anshan Iron and Steel Co., Ltd. is relatively simple, with pseudo-hematite, magnetite and quartz as the main minerals, and other mineral components are less. Qi Dashan Iron Ore Dressing Plant adopts stage grinding-rough subdivision-re-selection-magnetic separation-anion reverse flotation process, in which one section of grinding-0.074mm accounts for 60%, and the second section of grinding-0.074mm accounts for 85%. The ore of the powder ore bin is fed into a closed-circuit grinding consisting of a ball mill and a hydrocyclone, and the graded grit is returned to a section of the grinding machine, and the graded overflow is fed into the coarse subdivided cyclone to be classified into two materials. The coarse-grained material is fed into the re-election operation, and finally the re-elected concentrate is produced; the fine-grained material enters the magnetic separation operation composed of weak magnetic separation-high gradient and strong magnetic separation, and the primary mud and the secondary mud in the grinding product are taken off. . The mixed concentrate obtained by the magnetic separation operation is fed to the flotation for anion reverse flotation. The operation is a coarse and a fine three sweep, the collector is LKY, and the inhibitor is carboxymethyl starch. The fine-grained material contains 29% of iron grade. Through the weak magnetic-strong magnetic-reverse flotation combined process, 67% iron concentrate grade can be obtained, and the re-election concentrate and maglev concentrate are combined to become the final concentrate. In 2007, the production index of Qidashan Concentration Plant was: 28.26% of the original ore grade, 67.60% of the concentrate grade, 9.74% of the tailings grade, and the recovery rate of 82.73%.