关键词: 低品位, 磁铁矿, 磁黄铁矿, 脱硫

Abstract: In order to determine the development and utilization process of a low-grade low intensity magnetic iron ore in China and optimize the separation index，the beneficiation tests of process mineralogy and magnetic-flotation combined process were carried out for the ore.Through process mineralogy research， it is found that the particle size distribution of magnetite is relatively dispersed，mainly medium particles， belonging to medium-fine particle uneven distribution.The dissemination characteristics of magnetite in ore are complex，the dissemination particle size is uneven，and some magnetic iron minerals are associated with pyrrhotite，which brings certain difficulties to iron ore separation.The results of magnetic-flotation com⁃ bined process show that the combined process of pre-separation tailings discarding-stage grinding-stage magnetic separation-reverse flotation desulfurization has good effect on iron desulfurization，and qualified iron concentrate with sulfur content of 0.39%，TFe grade of 65.43% and TFe recovery of 71.36% is obtained.

Key words: low-grade, magnetite, pyrrhotite, desulfurization