Assessment of the Efficiency of Hematite Quartzite Enrichment Technologies

The present paper deals with the problem of developing an efficient technology for the enrichment of hematite ores. The aim of the research is to investigate the process properties of thinly disseminated hematite ores of Ukraine, taking into account their mineralogical characteristics, to develop flowsheets for the enrichment of hematite ores and to assess the efficiency of mineral separation during enrichment by gravity, magnetic, and flotation methods. The research was carried out on a sample of hematite ores from the Kryvyi Rih iron ore basin of Ukraine, which consisted of 9 mineralogical ore types, distinguished by the quantitative ratio of the main groups of ore and non-ore minerals. As a result of WLIMS magnetic separation with a magnetic field induction of 0.07 T, an iron-containing concentrate with a mass fraction of 63.5% iron was obtained from ore with a size of minus 0.074+0 mm, with a total iron recovery of 12.8%. It was found that with an increase in the magnetic field induction from 0.2 to 0.8 T, the recovery of total iron in the WHIMS magnetic product increased from 78.8 to 86.9%. The mass fraction of total iron in the WHIMS magnetic product was 57.9-59.8%. Losses of total iron with the non-magnetic product ranged from 21.2 to 13.1% with a mass fraction of total iron of 32-27.8%. The mass fraction of SiO2 in the magnetic product was 11-13.8%. Flotation research resulted in a hematite concentrate with a mass fraction of total iron of 64.05-65.95%, with iron recovery in the concentrate of 60.3-70.68%. Based on the results of process tests, seven variants of flowcharts for the enrichment of hematite ores were developed. The schemes were evaluated by the Hancock efficiency criterion, which ranged from 42.49-64.7%. The magnetic flotation technology for the enrichment of hematite quartzite was recommended for implementation. This technology makes it possible to obtain a commercial concentrate with a mass fraction of total iron of 37.02% from hematite ore with a mass fraction of total iron of 65.41%.