ORALS

SESSION: NonferrousTuePM2-R5	8th Intl. Symp. on Sustainable Non-ferrous Smelting & Hydro/Electrochemical Processing
Tue. 29 Nov. 2022 / Room: Arcadia 2
Session Chairs: Harn Wei Kua; Session Monitor: TBA

17:10: [NonferrousTuePM212] OS
INVESTIGATION OF SELECTIVE DISINTEGRATION FEASIBILITY OF GOLD-BEARING ORES
Nadezhda Nikolaeva¹ ; Tatyana Aleksandrova² ; ¹National mineral resources university, St. Petersburg, Russian Federation; ²National Mineral Resources University, Sain-Peterburg, Russian Federation;
Paper Id: 356 [Abstract]

New ore-processing plant projects often face problems in processing more complex and fine-grained minerals, resulting in additional costs and lengthening the crushing and grinding schemes to sufficiently unlocking. This trend could lead to an increase in energy consumption by a factor of 4 or more by 2030 compared to today. Already today about 2% of the electricity produced worldwide is used for this purpose. Thus, reduction of specific electric power consumption in processes of disintegration and enrichment of mineral raw materials is the actual task, taking into account the tendency to economy of natural resources, and also decrease impact on environment at processing of mineral raw materials [1-2]. One of decision way of problem is selective disintegration. A reasonable application of selective disintegration would not only allow the rock mass to be broken down to the required size, but also preconcentration at the classification stage to produce a pre-concentrate and to discharge the waste rock to the tailings [3-4]. Gold ores from the Bamskoe deposit were chosen as the object of study. Analysis of the material and chemical composition was carried out using atomic absorption, X-ray fluorescence method (Shimadzu EDX-7000). For mineralogical studies, optical methods of analysis, electron microscopy etc. were used in the work. Morphometric indicators were studied using computed tomography (SkyScan-1173 microtomograph). Experimental investigations were carried out on various installations: jaw crusher, roller crusher, impact crusher, ball mill, JK Drop Weight tester, Bond impact test, Bond ball and rod mill, Mastersaizer laser diffractometer, etc. Based on the strength and disintegration test data on mineralogical, textural and structural and physical properties of the minerals and on studies of ores crushing from the Bamskoe deposit in different types of crushers, it was found that rock-forming minerals are concentrated in large classes, especially in product of impact crushers (up to 81.85% of silica minerals in class - 4 + 2 mm). Based on the data obtained on testing of strength properties and disintegration indices from mineralogical, textural and structural and physical-technological properties of minerals and studies conducted on crushing ores of the Bamsky deposit in different types of crushers, it was found that the products of all crushers are characterised by a predominance of -4+2 mm class. As silica-minerals are the main rock-forming minerals, it was decided to look at the distribution of Si by size classes. In analysing the distributions of silica minerals, it was found that the extraction of silica minerals was maximised for the -4+2 mm grain size class. However, the impact crusher products are characterised by the highest recovery of silica minerals in this class (up to 81.85%). These results suggest that the impact crusher at the crushing stage can selectively break down this type of mineral at the fusion boundaries. This work was supported by the Russian Science Foundation (Рroject No. 19–17–00096).

References:
[1] Aleksandrova, T. N., Nikolaeva, N. V., Lvov, V. V., & Romashev, A. O. (2019). Ore processing efficiency improvements for precious metals based on process simulations. Obogashchenie Rud, 2019(2), 8-13. doi:10.17580/or.2019.02.02.
[2] Morrell,S., 2008, A method for predicting the specific energy requirement of comminution circuits and assessing their energy utilisation efficiency, Minerals Engineering, Vol. 21, No. 3. [3] Hopunov E. A. Selective destruction of mineral and anthropogenic raw materials (in beneficiation and metallurgy). - Yekaterinburg: UIPC LLC, 2013. - 429 p.
[4] Hesse, M., Popov, O., & Lieberwirth, H. (2017). Increasing efficiency by selective comminution. Minerals Engineering, 103-104, 112-126. doi:10.1016/j.mineng.2016.09.003.

SESSION: NonferrousWedAM-R5	8th Intl. Symp. on Sustainable Non-ferrous Smelting & Hydro/Electrochemical Processing
Wed. 30 Nov. 2022 / Room: Arcadia 2
Session Chairs: Vasily Lutsyk; Tatyana Aleksandrova; Session Monitor: TBA

12:20: [NonferrousWedAM03] OS
METHODS FOR THE EXTRACTION OF LOW-DIMENSIONAL NOBLE METAL STRUCTURES FROM REFRACTORY ORES
Tatyana Aleksandrova¹ ; Nadezhda Nikolaeva² ; ¹National Mineral Resources University, Sain-Peterburg, Russian Federation; ²National mineral resources university, St. Petersburg, Russian Federation;
Paper Id: 355 [Abstract]

The inability to extract nanoparticle size of gold is one of the reasons for the high losses of valuable components with tailings during benefication of gold-bearing ores. A promising direction for the development of technologies for processing of noble raw materials is the use of various methods of physical and energy impacts on raw materials and enrichment products. Examples of such effects may be microwave [1], electric pulse [2], magnetic pulse, electrochemical, ultrasonic and other types of effects. Such research in the field of microwave treatment application was conducted in the field of auxiliary beneficiation processes (drying), ore preparation (crushing and milling) and metallurgical processing (leaching, sintering) [3-4]. Flotation experiments were carried out on Laarmann Flotation Bench Test Machine. Elemental composition analysis was carried out using Shimadzu EDX 7000 X-ray fluorescence analyzer. Determination of gold content in the sample was carried out using atomic absorption analysis, the content of organic carbon was determined on the analyzer of organic carbon TOC-L, firm Shimadzu. For microwave treatment of samples a laboratory microwave oven was used. Analysis of products after microwave treatment was carried out using MV 2300 scanning electron microscopy, CamScan and a Mastersizer 2000 particle size analyzer from Malvern Instruments. For the investigated ores it was obtained that the main ore minerals are pyrite and arsenopyrite, barite, chalcopyrite and other minerals are present in insignificant amounts, the main rock-forming minerals are quartz, mica, carbonates and clay-sericite minerals. Contrasting surface properties of minerals with similar technological properties can be increased by applying different energy effects (MEMI, MIO, microwave, electrochemical treatment, etc.) at successive stages of raw material transformation, by regulating slurry conditioning conditions (duration and intensity of mixing, thermal treatment of slurry), as well as by developing and using selective reagent regimes. The analysis of obtained data confirms the possibility of enlarging low-dimensional noble metal particles using microwave treatment. On the basis of conducted research, the technology of extraction of low-dimensional structures of noble and non-ferrous metals based on application of physical and energy impact methods and application of flotation methods of extraction of valuable components with a modified "carrier" was developed. It was determined that pyrite predominates in carbonaceous flotation tails, arsenic content in the tails is 0.04%. Microwave treatment of carbonaceous tailings with furnace power of 1000 W and treatment time of 12-15 minutes for enlargement of nanoparticle size of gold to the size of a few microns was substantiated. This work was supported by the Russian Science Foundation (Рroject No. 19–17–00096).

References:
[1] Galushkin S. S., Vishnyak B.A., Smirnov V.N. The system of automatic control of humidity of bulk materials in streams // Journal of Mining Science - 2010. - Т. 187. P.40-42.
[2] Kurets V. I. et al. Research of electropulse method of selective destruction of ores, artificial materials and wastes of mining production // Journal of Mining Science - 2003. - Т. 154. P.138-141.
[3] Gorlenkov D. V., Gorlenkova I. V. , Beloglazov I. I. Selection of complete recovery of precious metals in the processing of copper-nickel alloys in hydrometallurgical way / Materials Science Forum, № 1, V 927, 2018. pp. 190 - 194 .I. Chojnacka, L. Rycerz, M. Berkani, M. Gaune-Escard, Journal of Alloys and Compounds 582 (2014) 505-510.
[4] Petrov G. V., Fokina S. B. , Boduen A. Y., Zotova I. E., Fidarov B. F. Arsenic behavior in the autoclave-hydrometallurgical processing of refractory sulfide gold-platinum-bearing products / international Journal of Engineering and Technology, № 2, Т 7, 2018. P 35 - 39 .