关键词: 极贫赤铁矿石, 阶段磨矿, 磁选, 反浮选

Abstract: The iron content of the ore mined from a large iron mine is 19.41%，and the iron-bearing minerals are mainly hematite，limonite and magnetite. Gangue minerals mainly include quartz，ortho⁃ clase，actinolite and so on. On the basis of process mineralogy and property analysis，the separation test was carried out by one stage grinding-low intensity magnetic separation-high intensity magnetic separa⁃ tion，one stage mixed concentrate via two stage grinding- low intensity magnetic separation-high intensity magnetic separation，and second stage mixed concentrate via anionic reverse flotation process. The grind⁃ ing fineness of the first stage is -0.074 mm 60%，the magnetic field intensity of the first stage low intensity magnetic separation is 200 kA/m，the magnetic induction intensity of the first stage high intensity magnetic separation is 0.9 T，the second stage grinding fineness on the first stage magnetic separation mixed concen⁃ trate is -0.074 mm 90.81%，the magnetic field intensity of the second stage low intensity magnetic separa⁃ tion is 184 kA/m，and the magnetic induction intensity of the second stage high intensity magnetic separa⁃ tion is 1.0 T. The two-stage magnetic separation mixed concentrate uses NaOH as the pH regulator，KDF as the inhibitor，CaO as the activator，TDK-II as the collector，through one roughing，one cleaning and three scavenging reverse flotation. The iron grade of the concentrate is 66.45%，the metal recovery rate is 53.92%，and the iron grade of the tailings is 10.62%. The test process is simple and reasonable，which provides a technical basis for the efficient utilization of similar ores.

Key words: extremely poor hematite ore, stage grinding, magnetic separation, reverse flotation