Abstract: In order to use an iron concentrate to process ultra-pure iron concentrate with an iron grade of more than 71%，based on the analysis of mineral properties of ordinary iron concentrate，experimental studies on grinding，magnetic separator separation，elutriator separation and flotation were carried out. The test results show that the ordinary iron concentrate is ground to −0.043 mm 75.56%，and the grinding prod‐ ucts are separated by an elutriation machine with fixed magnetic field of 95.52 kA/m，circulating magnetic field of 83.58 kA/m，compensation magnetic field of 83.58 kA/m，and rising water volume of 1 200 L/h.Un‐ der the conditions of flotation concentration of 40% and cationic collector Gy dosage of（60+30+15）g/t，the ultra-pure iron concentrate with yield of 92.55%，iron grade of 71.35% and iron recovery of 94.10% was fi‐ nally obtained through a closed-circuit reverse flotation test of one roughing and two cleaning. The recom‐ mended process flow for the production of ultra-pure iron concentrate by ordinary iron concentrate is grind‐ ing-elutriation machine magnetic separation-reverse flotation.

Key words: ultra-pure iron concentrate, flotation, magnetic separation