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

Öz

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.

Anahtar Kelimeler

• Iron ores
• magnetite
• magnetic separation
• gravity separation
• scrubbing

DÜŞÜK TENÖRLÜ MANYETİT CEVHERİNİN MANYETİK AYIRMA VE YERÇEKİMİ İLE ZENGİNLEŞTİRİLMESİ: TANE BOYU ETKİSİ

Öz

This study compares the efficiency of different methods in beneficiation of iron ore from Doğanşehir (Malatya) region. It is a low grade ore with 27.43 % Fe content that requires concentration to meet the specifications of blast furnace feed. The ore mainly contains magnetite, ferro-actinolite and magnesioferrite. 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 extend, but 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.

Anahtar Kelimeler

• Iron ores
• magnetite
• magnetic separation
• gravity separation
• scrubbing

Kaynakça

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