ENRICHMENT OF LOW-GRADE MAGNETITE ORE BY MAGNETIC AND GRAVITY SEPARATIONS: EFFECT OF PARTICLE SIZE

Abstract

This study compares the efficiency of different methods in beneficiation of iron ore from Doğanşehir (Malatya) region. It is a low-grade ore containing 27.43 % Fe which requires concentration to meet the specifications of blast furnace feeds. The main mineral composition of ore is magnetite and also contains magnesioferrite, ferro-actinolite and calcite minerals. The collected samples were classified into different size fractions after size reduction and then subjected to different gravimetric and magnetic separation methods for concentration. The results showed that particle sizes affected the concentrations to a large extent and generally cleaner concentrates were obtained at finer sizes for a certain separation method. On the other hand, wet magnetic separation yielded comparably better results than gravimetric methods. A concentrate assaying 65.66 % Fe and 0.38 % K2O+Na2O was obtained with 78.11 % recovery by wet magnetic separation. It was concluded that concentrates meeting blast furnace specifications could be obtained from this low-grade iron ore. It was also concluded that the proposed separation flow sheet can be applied to similar low-grade iron ores in the region. © 2021 Union of Chambers of Engineers and Architects of Turkey. All rights reserved.