Effect of microwave pretreatment on grinding of iron ore Article uri icon

abstract

  • The effect of microwave radiation on grinding of an iron ore was investigated. Significant reductions in Bond work index are demonstrated for microwave treated samples. These reductions are sensitive to the power applied in relation to the exposure time of the mineral to microwaves. The best result was obtained with an exposure time of 3 min, achieving a reduction of 41 %25 in Bond work index. The grinding kinetics shows that there is a significant effect on the production of fines for the treated sample, since for each grinding time tested, the distribution of passing cumulative size was higher respect to the sample non-Treated, particularly for short times. The results obtained indicated important improvements in the size reduction, due to microwave energy, produced microfractures intergranular and transgranular level, caused by differential heating and subsequent thermal expansion between mineral phases absorbing and transparent to microwave radiation. These changes are supported by analytical studies of X-ray diffraction and scanning electron microscopy. It was confirmed that microwave pre-Treatment has a significant positive effect on the efficiency of the energy applied to the grinding of iron ore studied.

publication date

  • 2017-01-01