关键词: 超级铁精矿, 磁性铁, 弱磁选, 淘洗磁选, 反浮选

Abstract: A domestic concentrator now produces an iron concentrate with TFe grade of 70.08%and main impurity SiO2 content of 1.13%.The main iron mineral is magnetite，accounting for 98.92%.In order to determine the feasibility of processing this iron concentrate to produce ultra-pure iron concentrate，a systematic beneficiation test was carried out.The results show that the content of -0.076 mm in iron con⁃ centrate is 79.82%，the dissociation degree of coarse-grained monomer is low，the iron grade is low and the SiO2 grade is high.In order to obtain high-quality ultra-pure iron concentrate，fine grinding and deep separation must be carried out.The combined process of ball mill grinding（-0 .038 mm 95%）-one rough⁃ ing-one cleaning low-intensity magnetic separation-elutriation magnetic separation-one roughing-one cleaning reverse flotation was adopted.When the magnetic field intensity of low-intensity magnetic rough ⁃ ing was 128 kA/m，the magnetic field intensity of cleaning was 80 kA/m，the rising water volume of wash ⁃ ing was 1.0 m3 /h，the dosage of sodium carbonate in reverse flotation was 500 g/t，the dosage of MK618 roughing was 140 g/t and the dosage of cleaning was 60 g/t，the ultra-pure iron concentrate with yield of 32.60%，iron grade of 71.55%and SiO2 grade of 0.136%was obtained.This process provides a reliable technical basis for the industrial production of ultra-pure iron concentrate.

Key words: ultra-pure iron concentrate, magnetic iron, low-intensity magnetic separation, elutriation? magnetic separation, reverse flotation