Mineral processing of vein quartz from the Fenkina-Lampi deposit (Karelia)
Svetova E. N., Shanina S. N., Pikulev V. B., Bukchina O. V.
Zapiski RMO (Proceedings of the Russian Mineralogical Society). 2021. V. 150. N 6. P. 113-136
The paper covers the results of the mineralogical and process investigation of the vein quartz of the Fenkina-Lampi deposit in Karelia, considered as a promising source of high-purity quartz raw materials. The main mineralogical features of the quartz which make it possible to predict the quality of quartz raw materials and contribute to the choice of optimal process flow are considered. It is shown that quartz is characterized by high water content, which complicates the processing by traditional methods. According to IR spectroscopy data, the basic amount of water in quartz is present in molecular form as fluid inclusions. The chromatographic analysis of the gas phase released from quartz at its heating detects Н2О, СО2, CO, N2 and hydrocarbon gases. The gas release takes place both at low-temperature (100–600 °С), and at high-temperature (600–1000 °С) ranges, which generally negatively characterizes the quartz as a raw material for high-quality fused glass. A process flow including electromagnetic separation, microwave, and ultrasound treatment, fractional acid leaching in HCl and HF is proposed. The effect of individual processing steps on the quality of the obtained quartz concentrates was analyzed. It has been shown that the use of directed operations, taking into account the technological features of quartz, can significantly improve the quartz products quality and reduce the total trace element content from 529 ppm to 43 ppm in concentrates with the fineness of –0.315 + 0.2 and –0.2 + 0.1 mm.
Keywords: vein quartz, technological mineralogy, processing, trace-elements, IR spectroscopy, gas chromatography, electron microscopy, ICP-AES, Fenkina-Lampi deposit