National Mineral Resources University (University of Mines) (Russia):

Purevdash M., Researcher, Ph. D. in Engineering Sciences, moogi@mail.ru
Dolivo-Dobrovolskaya G. I., Professor, Doctor of Geology and Mineralogy, kafmetall@mail.ru
Saltykova S. N., Associate Professor, Ph. D. in Engineering Sciences, ssn_58@mail.ru
Georgiyeva E. Yu., Assistant, Ph. D. in Engineering Sciences, georgieva_eyu@mail.ru

The article presents the results of studies performed on cut-off grade copper-molybdenum sulfide ore from the Erdenet Mining Complex with a view to investigate effect of bacterial liquor upon physical characteristics of the ore. The ore chemical and mineral compositions are described, the experimental data related to the ore grinding prior and after treatment with bacterial liquor are presented. The material grinding time was 5 and 10 minutes. Sieve analysis was performed, and reduction ratio and size modulus were determined. True density and total porosity of the samples were determined in the course of the investigations. Feed ore and treated ore magnetic fractions compositions were determined by means of spectroscan MAX-G. Effect of sulfuric acid solution upon magnetic fraction was studied. 9 % sulfuric acid solution was used as initial solution, liquid to solid ratio was 1 : 6, duration of acid effect was 15 days. pH medium and Fe²⁺, Fe³⁺ concentration in solution were under control in the course of the experiments. In order to study the effect of silicate bacteria upon copper-molybdenum sulfide ores in detail, microstructure analysis was performed by means of TESCAN scanning electron microscope. The experimental data permit to draw a conclusion, that under the effect of silicate bacteria, ore grains surface area is increased, thus improving liberation of copper-bearing minerals in subsequent ore processing and saving energy costs in ore disintegration.

1. Adamov E. V., Panin V. V. Biogidrometallurgicheskiye protsessy v tekhnologii pererabotki mineralnogo syr'ya (Biohydrometallurgical processes in minerals processing technology). Leningrad, Nauka, 1990.
2. Adamov E. V., Panin V. V. Bakterialnoye i khimicheskoye vyshchelachivaniye metallov iz rud. Itogi nauki i tekhniki (Bacterial and chemical leaching of metals from ores. Results of science and engineering). Obogashcheniye poleznykh iskopayemikh (Minerals processing). 1974, Iss. 8.
3. Adamov E. V., Panin V. V. Biotekhnologiya metallov. Kurs lektsiy (Biotechnology of metals. Course of lectures). Moscow, MISIS, 2005.
4. Gusev M. V., Mineyeva L. A. Mikrobiologiya (Microbiology). Moscow, MGU (MSU), 1992.
5. Karavayko G. I., Rossi J., Agate A., Grudev S., Avakyan Z. A. Biogeotekhnologiya metallov. Prakticheskoye rukovodstvo (Biogeotechnology of metals. Manual of practice). Moscow, Center of International Projects, GKNT, 1989.
6. Karavayko G. I., Grudev S. N. Biogeotekhnologiya metallov (Biogeotechnology of metals). Moscow, GKNT, 1985.
7. Karavayko G. I., Kuznetsov S. I., Golomzik A. I. Rol mikroorganizmov v vyshchelachivanii metallov iz rud (Role of microorganisms in leaching of metals from ores). Moscow, Nauka, 1972.
8. Kuzyakina T. I., Khaynasova T. S., Levenets O. O. Vestnik KRAUNTs. Nauki o Zemle — Bulletin of Kamchatka Regional Association «Educational-Scientific Center». Earth Sciences, 2008, No. 2, Iss. 12, pp. 76–86.
9. Naboychenko S. S., Smirnov V. I. Gidrometallurgiya medi (Hydrometallurgy of copper). Moscow, Metallurgiya, 1974.
10. Polkin S. I., Adamov E. V., Panin V. V. Tekhnologiya bakterialnogo vyshchelachivaniya tsvetnykh i redkikh metallov (Technology of nonferrous and rare metals bacterial leaching). Moscow, Nedra, 1982.