JSC “Center of Earth Sciences, Metallurgy and Ore Benefcation”, Almaty, Kazakhstan:

A. K. Koyzhanova, Leading Researcher, e-mail: aigul_koizhan@mail.ru
G. A. Arystanova, Senior Researcher
D. M. Esimova, Engineer

Central Scientific-Research Geology-Survey Institute of Non-ferrous and Noble Metals, Moscow, Russia:

G. V. Sedelnikova, Deputy Director, e-mail: gsedelnikova@mail.ru

Bacterial-chemical leaching is one of prospective technologies of processing of gold-bearing raw materials (ores, old concentration and cyanidation tailings). It does not require big material inputs and does not cause any ecological problems. There are shown the results of biochemical leaching of refractory sorption tailings for the purpose of extraction of sulfide-associated gold. Representative sampling process was carried out together with investigation of chemical, mineral and phase compositions of sorption tailings of gold mining factory Altyntau Kokshetau. Sorption tailings are finely grinded material. Sulfide minerals content is 32%. Main sulfides are arsenopyrite (22.7%) and pyrite (9%). Considerable part of gold (68.9%) is finely ingrained in sulfides. Application of cyanidation is low-efficient. Gold extraction is not more than 32.2%. Increased content of gold is in rock-forming minerals (17.2%). Gold particle coarseness varies within 0.03–0.05 mm. Optimal concentration of Silverman and Lundgren 9K nutrient medium was chosen for acidophile carbothionic bacteria, used for bioleaching of sorption tailings. Influence of various temperature conditions (20, 28 and 35 ^oС) on bioleaching process was investigated. Adapted bacteria At. Ferrooxidans were used for sorption tailing leaching during 5–7 days. There were investigated the methods of combination of bacterial leaching process with preliminary acid processing and gypsumchlorite processing of biooxidation residues before cyanidation. About 78% of gold is extracted in optimal mode of cyanidation of biooxidation residues.

1. Koizhanova A., Mukusheva A., Osipovskaya L., Erdenova M. Study of Sorption Kinetics in Processes of Precious Metals Recovery. Proceedings of XXVI International mineral Prosessing Congress — IMPC 2012. New Delhi, India, 24–28 September 2012. pp. 590–601.
2. Sedelnikova G. V. Sravnenie avtoklavnogo i bakterialnogo vyshchelachivaniya (Comparison of autoclave and bacterial leaching). Zoloto i tekhnologii = Gold and technologies. 2014. No. 2 (24). pp. 110–115.
3. Sedelnikova G. V., Kim D. Kh., Ibragimova N. V. Sravnenie sovremennoy tekhnologii kuchnogo bakterialnogo vyshchelachivaniya s traditsionnoy flotatsionno-tsianistoy pererabotkoy upornoy zolotosulfidnoy medno-tsinkovoy rudy (Processing of refractore sulphide Au – Cu – Zn ore: modern bacterial heap leaching vs. traditional cyanide). Rudy i metally = Ores and Metals. 2015. No. 3. pp. 59–69.
4. Kononov Yu. S., Patrushev V. V. Stendovye ispytaniya sorbtsionnogo vyshchelachivaniya zolotosoderzhashchego kontsentrata (Bench testings of sorption leaching of gold-bearing concentrate). Tsvetnye Metally = Non-ferrous metals. 2010. No. 11. pp. 41–43.
5. Gusakov M. S., Krylova L. N., Moshchanetskiy P. V., Chzhen Chzhi Khun. Vliyanie fiziko-khimicheskikh parametrov rastvora na okislitelnuyu aktivnost bakteriy i vyshchelachivanie sulfidnykh kontsentratov (Influence of physical and chemical parameters of solution on oxidation activity of bacteria and sulfide concentrates leaching). IX Kongress obogatiteley stran SNG : sbornik materialov (IX Congress of dressers from the CIS countries: collection of materials). Moscow, 2013. Vol. 1. pp. 210–215.
6. Gericke M., Seyedbagheri A., Neale J. W., van Staden P. J. Advancements in the approach to research and design of heap bioleaching processes. 19th International Biohydrometallurgy Symposium (IBS 2011). Changsha, China, 18–22 September 2011. pp. 698–705.
7. Grace Ofori-Sarpong, Kwadwo Osseo-Asare, Ming Tien. Fungal biotransformation of anthracite-grade carbonaceous matter. Effect on gold cyanide uptake. 19th International Biohydrometallurgy Symposium (IBS 2011). Changsha, China, 18–22 September 2011. pp. 445–451.
8. Fomchenko I. V., Muravev M. I., Kondrateva T. F. Pererabotka sulfidnykh kontsentratov i promproduktov, soderzhashchikh zoloto i tsvetnye metally, s primeneniem biogidrometallurgii (Processing of sulfide concentrates and middlings, containing gold and non-ferrous metals, with application of biohydrometallurgy). Materialy mezhdunarodnogo soveshchaniya “Innovatsionnye protsessy kompleksnoy i glubokoy pererabotki mineralnogo syrya” (Plaksinskie chteniya-2013) (Materials of international meeting “Innovation processes of complex and deep processing of mineral raw materials” (Plaksin readings–2013)). Tomsk : Publishing House of Tomsk Polytechnic University, 2013. pp. 271–284.
9. Shketova L. E., Kopylova N. V., Verkhozina V. A. Issledovaniya v oblasti kuchnogo biovyshchelachivaniya sulfidnykh polimetallicheskikh rud (Investigations in the area of heap bioleaching of sulfide polymetallic ores). Materialy VII Moskovskogo mezhdunarodnogo kongressa “Biotekhnologiya: sostoyanie i perspektivy razvitiya” (Materials of the VII Moscow international congress “Biotechnology: state and prospects of development”). Moscow, March 19–22, 2013. Part 2. pp. 191, 192.
10. Drozdov S. V., Proskuryakova I. A., Belousova N. V. Vliyanie temperatury, kontsentratsii tsianida natriya i krupnosti iskhodnogo materiala na intensivnoe tsianirovanie zolota iz sulfidnogo gravitatsionnogo kontsentrata (Influence of temperature, concentration of sodium cyanide and lumpiness of initial material on intensive cyanidation of gold from sulfide gravitation concentrate). Tsvetnye Metally = Non-ferrous metals. 2011. No. 10. pp. 64–68.
11. Gusakov M., Krylova L. Technological properties of solutions of ferric iron produced by iron-oxidizing microorganisms. Proceedings of XXVI International mineral Prosessing Congress — IMPC 2012. New Delhi, India, 24–28 September 2012.
12. Brittan M., Plenge G. Estimating process design gold extraction, leach residence time and cyanide consumption for high cyanide-consuming gold ore. Minerals and Metallurgical Processing. 2015. Vol. 32, No. 2. pp. 111–120.