Justification of preliminary microwave exposure for the disintegration of fine-grained gold-bearing ores

The paper investigates the effect of preliminary exposure of finely disseminated goldbearing ores to SHF radiation with a view to improving the process of disintegration of mineral grains with contrasting electromagnetic properties. The presence of finely disseminated and refractory gold in gold rocks complicates the process of gold extraction. The paper presents one of the promising ways to solve this problem, viz. preliminary exposure of gold-bearing rock to microwave radiation. The paper describes the examination of various specimens of gold-bearing rocks using X-ray diffractometry and scanning electron microscopy, as a result of which the phase composition of the specimens and structure of the dissemination of gold grains are determined. The specimens were examined with an ADP2—01 X-ray diffractometer and a Phenom ProX scanning electron microscope. A matrix model with conductive inclusions is produced, based on which the effect of heating finely disseminated gold in a microwave field is analyzed. Laboratory experiments were performed, exposing the specimens to microwave radiation in various modes. The simulation data are confirmed by experimental data, which in turn made it possible to determine the optimal parameters of time and power of microwave heating. Also, instrumental examination was performed to study changes in the structural state (opening of main splitting cracks) of ore specimens after microwave exposure; the optimal mode of microwave exposure is substantiated.

Kadyrbay A. K. Justification of preliminary microwave exposure for the disintegration of fine-grained gold-bearing ores. MIAB. Mining Inf. Anal. Bull. 2021;(4-1):118—128. [In Russ]. DOI: 10.25018/0236_1493_2021_41_0_118.

Kadyrbay A. K., graduate student, kadyrbai.kadr@gmail.com, National Research Technological University «MISiS» , Moscow, Russia.

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