Abstract: To obtain a high-grade DR-grade iron concentrate product and reduce the total content of SiO2 and Al2O3,an
optimization study of the grinding-magnetic separation process was conducted on a high-grade iron ore sample from Africa. The
results show that the ore has a TFe grade of 65. 92%,with iron mainly occurring in hematite,limonite,and magnetite,which are
the primary target minerals for recovery. Under the optimal conditions of a primary grinding fineness of 60% passing 0. 074
mm,primary low-intensity magnetic field intensity of 79. 6 kA/ m,primary high-intensity magnetic field intensity of 398. 0
kA/ m,cleaning high-intensity magnetic field intensity of 159. 2 kA/ m,and scavenging high-intensity magnetic field intensity of
398. 0 kA/ m,a mixed magnetic concentrate was obtained with a TFe grade of 68. 11%,a combined SiO2 +Al2O3 content of
1. 20%,and an iron recovery of 82. 96%. Product analysis indicates that the mixed magnetic concentrate is mainly composed of
hematite,limonite,and magnetite,demonstrating that the primary magnetic iron minerals in the ore were effectively enriched.
The study concludes that the grinding-magnetic separation process can achieve efficient separation of hematite and magnetite
from this African iron ore,exhibiting significant advantages,particularly in controlling aluminum and silicon impurity contents,
thereby producing a high-quality DR-grade iron concentrate.