The experience of heap leaching (HL) was analyzed in the following cold climate regions: Alaska, Western regions of the United States, Canada, Kazakhstan, and Russia. The disadvantages of the developed domestic mobile units were uncovered, and the potential for creating HL mobile units was assessed to enable a year-round use of the technology, including in the cryolithozone. The results are presented, which were obtained during investigation of the material composition of the study object, i.e., technogenic gold-containing deposits of the Transbaikal region. The main element content of the mineral raw materials of the technogenic deposits was as follows: Au — 0.35 g/m3, Ag — 3.9 g/m3, SiO2 — 69.3 %, Al2O3 — 15.4 %, Fe2O3 — 5.9 %, CaO — 0.21 %, and MgO — 1.15 %. The phase forms of gold included: cyanidable (intergrown) — 2.3 %, “sealed in quartz” — 13.5 %, “enveloped” — 28.6 %, in magnetite — 55.6 %. A continuous process line was developed, which included the following four unit modules: gravity concentration, first stage of leaching (tank leaching), second stage of leaching (heap leaching), and sorption. The layout of the continuous process line (HL option during the period of subzero temperatures) is provided.
The optimal values of the main process parameters of gravity concentration, as well as the first and second stages of leaching have been established experimentally. Prior to tank leaching, an active multiple-reagent solution based on sodium chloride, water and ozone compounds was prepared in a sealed electrochemical reactor. The tank was partitioned into three sections, in which the following operations were carried out in series: chemical opening of the gold-containing minerals; chlorine removal from the geomaterial; and tank leaching of gold. The total duration of heap leaching was 365 days, which was achieved by using two technological options: option 1 (195 days) — classic HL method (from early April to mid-October), option 2 (170 days) — heap leaching in stationary concrete cuvettes using engineering solutions during the period of subzero temperatures (from mid-October to the end of March). A schematic layout of the stationary concrete cuvette constructed in a special way and buried within a 5 to 8 m layer of soil above the ground level with shielding of the upper surface of the stack (heat-insulating covering, clay, large pieces of ore, sulfide rocks) is provided. Product solution drainage was used at various heights, and perforated rigid PVC pipes were used for supplying warm air deep inside the material. The recovery of gold from the technogenic raw materials was increased on average by 27.1 % due to a year-round heap leaching with the use of two technological options: 1 — by 28.7 % (from 58.1 to 86.8 %) using a classic HL method, and 2 — by 27.4 % (from 58.1 to 85.5 %) by using HL in stationary concrete cuvettes. It is proposed to utilize the secondary waste of the HL field (total of five types) in the road-building and construction industries.
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References
V. Zh. Arens, Physicochemical Geotechnology: Study Guide [in Russian], Izd. MGTU, Moscow (2001).
V. Zh. Arens, Geotechnology [in Russian], MISiS, Moscow (2018).
Heap Leaching of Noble Metals, ed. by M. I. Fazlullin [in Russian], Izd. AGN, Moscow (2001).
M. A. Medkov, A. V. Taskin, S. I. Ivannikov, and A. A. Yudakov, “Concentration and recovery of finely dispersed gold from a technogenic waste of the Kedrovka gold deposit,” Tsvetnye Metally, No. 4, 41–46 (2017).
I. I. Kovlekov, V. A. Sherstov, L. N. Knyazev, P. S. Varlakov, and A. A. Dmitriev, “Heap leaching of gold-containing ores in the North,” GIAB, No. 12, 279–282 (2004).
V. P. Myazin, “System analysis of the development status of gold mining technology and machinery in Transbaikalia. Technological and ecological issues,” Vest. Zab. Tsentr. RAEN, No. 1, 87–93 (2008).
D. M. Shesternev, “Rock weathering in the cryolithozone,” Vest. Zab. Tsentr. RAEN, No. 1, 25–29 (2008).
D. M. Shesternev and V. P. Myazin, “Prospects of year-round heap leaching of gold from poor ores when developing shallow deposits of the Transbaikal cryolithozone,” Conf. Proc. “Fundamental problems of formation of technogenic geoenvironment,” IGD SO RAN, 1, 236–241 (2010).
L. V. Shumilova and Yu. N. Reznik, Combined Methods of Cuvette and Heap Leaching of Gold-resistant Materials based on the Targeted Photo-electrochemical Exposure [in Russian], ZabGU, Chita (2012).
L. V. Shumilova, Scientific Justification of Innovative Gold Recovery Technology (Development and Testing in Transbaikalia) [in Russian], Palmarium Academic Publishing, Germany (2014).
V. Zh. Arens and A. S. Chernyak, “Chemical and economic aspects of leaching,” Gornyi Zhurnal, No. 12, 5–7 (1994).
On Improvement of Gold Production Methods in the USA and Canada. Analytical Review [in Russian], TsSIS, Moscow (1995).
A. Ye. Vorobyov and T. V. Chekushina, “Grouping of ore stacks for heap leaching,” Rudy i Metally, No. 5, 65–76 (2000).
L. V. Shumilova, “Gravitational and electrochemical method for extracting gold from technogenic placers,” Gorn. Inf.-Anal. Bull., No. 5 (Special issue 19), 186–192 (2015).
D. M. Shesternev and V. P. Myazin, “Gold heap leaching in the permafrost zone of Transbaikalia,” J. Mining Sci., 46, 5, 587–592 (2010).
H. Gu, X. Yang, Zh. Nie, J. Deng, L. Duan, et al., “Study of late-Mesozoic magmatic rocks and their related copper-goldpolymetallic deposits in the Guichi ore-cluster district, Lower Yangtze River Metallogenic Belt, East China,” Int. Geol. Rev., 60, No. 11-14, 1404–1434 (2018).
M. Mawby, “Australasian Mining and Metallurgical Operating Practices,” The Sir Maurice Mawby Memorial, Carlton, Vic., Australasian Institute of Mining and Metallurgy, 2 (2013).
T. Matthews, “Dilution and ore loss projections: Strategies and considerations,” SME Annual Conference and Expo and CMA 117th National Western Mining Conference, Mining: Navigating the Global Waters, Denver, 529–532 (2015).
M. Seredkin, A. Zabolotskii and G. Jeffress, “In situ recovery, an alternative to conventional methods of mining: exploration, resource estimation, environmental issues, project evaluation and economics,” Ore Geol. Rev., 79, 500–514 (2016).
L. Sinclair and J. Thompson, “In situ leaching of copper: Challenges and future prospects,” Hydrometallurgy, 157, 306–324 (2015).
A. V. Lalomov, R. M. Chefranov, V. A. Naumov, O. B. Naumova, W. LeBarge, and R. A. Dilly, “Typomorphic features of placer gold of Vagran cluster (the Northern Urals) and search indicators for primary bedrock gold deposits,” Ore Geol. Rev., 85, 321–335 (2017).
A. Barba, V. F. Devbilov, and Yu. N. Filtsev, RF Patent No. 2510669 С2, “Method for extracting noble metals from stubborn raw materials,” appl. date: August 14, 2012, publ. date: April 10, 2014, Bul. No. 10.
A. G. Sekisov, Yu. I. Rubtsov, Yu. N. Reznik, A. Yu. Lavrov, and D. V. Manzyrev, RF Patent No. 2475547 С1, “Method for extracting gold from mineral raw materials,” appl. date: June 22, 2011, publ. date: February 20, 2013, Bul. No. 5.
A. G. Sekisov, Yu. N. Reznik, N. V. Zykov, et al., RF Patent No. 2007118333 A, “Method for cuvette-heap leaching of metals from a mineral mass,” appl. date: May 16, 2007, publ. date: November 27, 2008, Bul. No. 9.
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Translated from Metallurg, Vol. 64, No. 10, pp. 56–64, October, 2020.
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Shumilova, L.V., Khatkova, A.N., Myazin, V.P. et al. Year-Round Heap Leaching of Gold in Cryolithozone. Metallurgist 64, 1046–1056 (2021). https://doi.org/10.1007/s11015-021-01086-0
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DOI: https://doi.org/10.1007/s11015-021-01086-0