关键词: 铁矿, 湿式预选, 阶段磨矿, 弱磁选, 磁选柱

Abstract: There is 37.21% TFe in a foreign iron ore，with a distribution rate of magnetic iron reach⁃ ing 95.21%. It is classified as an acidic ore dominated by magnetite，with low levels of harmful elements S and P，and a primary impurity SiO₂ content of 44.72%. To provide a reference for the development and utili⁃ zation of this ore，a combined process of wet pre-selection—stage grinding—low-intensity magnetic sepa⁃ ration—magnetic separator column separation was tested. The results showed that under a wet pre-selec⁃ tion magnetic field intensity of 280 mT，a pre-selected concentrate with a TFe grade of 46.53% and a recov⁃ ery rate of 97.39% was obtained. When the pre-selected concentrate via primary grinding to a fineness of 60% passing 0.076 mm and a magnetic field intensity of 250 mT，the primary magnetic separation concen⁃ trate achieved a TFe grade of 56.85% and a recovery rate of 96.21%. At a secondary grinding fineness of 85% passing 0.043 mm，a TFe grade of 70.42% and a recovery rate of 98.31% were obtained after one roughing and one cleaning stage of low-intensity magnetic separation. Further research indicated that using magnetic separator column separation under coarser grinding conditions (68% passing 0.043 mm) and an upward water flow rate of 250 mL/s yielded a high-quality concentrate with a TFe grade of 70.19% and a re⁃ covery rate of 97.53%. This approach achieved comparable indicators while significantly reducing grinding energy consumption. The closed-circuit test of the entire process ultimately produced a concentrate with a TFe grade of 70.19%，a SiO₂ content reduced to 1.91%，and a TFe recovery rate of 90.32%. The research results provide a feasible and efficient energy-saving process for the separation of this type of iron ore.

Key words: iron ore, wet pre-concentration, staged grinding, low intensity magnetic separation, mag? netic column