Effect of FLUMAG M flux on strength properties of iron ore pellets

Currently, the most common fluxing additive to pellets is d mite CaCO₃ ·MgCO₃ , in which the content of magnesium oxide can be from 17 to 22 %. But if it is necessary to increase magnesium oxide in pellets, it is necessary to increase the dosage of dolomite, and thus the iron content decreases, which entails a decrease in yield ratio at subsequent processing. One of the fluxes containing magnesium is brucite. Compared with dolomite, magnesium oxide content in pure brucite is more than 3 times higher. The basis of FLUMAG M flux is brucite. The content of magnesium oxide in it is not less than 55 %. The paper presents series of laboratory studies on the effect of FLUMAG M flux dosage on pelletizing ability of the charge and such properties of iron ore pellets as compressive, impact and abrasion strength. We have made the tests on raw and fired pellets with FLUMAG M flux. The comparative analysis of strength properties of the pellets obtained with the use of FLUMAG M and limestone was performed. Content of the binder – bentonite and magnetite concentrate for all experiments remained unchanged. The results of these experiments indicate that FLUMAG M does not interfere with charge pelletizing ability. The strength of raw pellets for discharge and compression with FLUMAG M flux has small deviations from the pellets with the addition of limestone. Roasted pellets with the addition of FLUMAG M flux have higher strength than ones with limestone. The higher difference in strength properties is observed at the flux content of 2 %.

brucite, FLUMAG M, strength properties, raw pellets, roasted pellets, pelletizing ability, impact, compression, abrasion, quality

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