Iron recovery from acid waste solutions after bio-oxidation of gold-bearing sulfide ore concentrates

The laboratory-scale test data on iron recovery from acid waste solutions after bacterial leaching of gold-bearing sulfide ore concentrates are presented in the article. The tests were aimed to recover iron from arsenic-bearing acid waste and to enhance mineral management efficiency and incremental production. The tests were carried out using a solution sampled from the bio-oxidation plant at Navoi Mining and Metallurgical Combinat. The prime objective of the study was optimization of acid waste solution processing and iron recovery from solution without arsenic. Both iron and arsenic are useful, separately. Ferric hydroxide is a source of pigments for ink making, or can be used for iron production (cast iron, steel). Gypsum is a product of high demand in construction. However, the mixture of these products disables their utility. It is required to remove limestone in order to neutralize acid solutions to produce pure ferric hydroxide. The preliminary study was aimed to separate arsenic and iron by means of settling. The settling quality was assessed from the analysis of their concentration in solution after addition of new reagent portion and measurement of pH value. Iron was settled using lime milk, ammonia water and sodium hydrate. Based on the lab-scale testing results, a flowchart is proposed, including settling of iron and arsenic from acid waste by ammonia water and arsenic removal from settlings by dissolving by sodium hydrate. The research aimed at optimization of ammonia settling and acid treatment of settlings (influence of NaOH concentration, temperature, S:L ratio, process duration) and at determination of contents of elements in the settling after acid treatment.

Sanakulov U. K., Tazhibaev D. Yu., Ergashev U. A. Iron recovery from acid waste solutions after bio-oxidation of gold-bearing sulfide ore concentrates. MIAB. Mining Inf. Anal. Bull. 2021;(3-1):127—135. [In Russ]. DOI: 10.25018/0236_1493_2021_31_0_127.

Ergashev U. A., Dr. Sci. (Eng.), Associate Professor, Head of the Technological Department of NMMC, Tashkent State Technical University named after Islam Karimov;
Sanakulov U. K., Cand. Sci. (Eng.), Researcher, Tashkent State Technical University I. Karimova, Institute of Nuclear Physics, Academy of Sciences of the Republic of Uzbekistan;
Tazhibaev D.Yu., Head of the Laboratory of the Institute of Nuclear Physics of the Academy of Sciences of the Republic of Uzbekistan, Navoi Mining and Metallurgical Combine.

1. Sanakulov K. S., Ergashev U. A. Teoriya i praktika osvoyeniya pererabotki zolotosoderzhashchikh upornykh rud Kyzylkumov: monorafiya [Theory and practice of development of processing of gold-bearing refractory ores of Kyzylkum : monoraph]. GP NIIMR”, Tashkent, 2014. 297 p. [In Russ].

2. Sanakulov K., Tagaev I. A. Possibilities of processing the mineralized mass of the Muruntau mine and the tailings of the gold recovery plant by the bacterial method Tsvetnye Metally. 2020, no. 2, Pp. 5—11. [In Russ].

3. Egorova T. A. Osnoy biotekhnologii: monografiya [Fundamentals of biotechnology: monograph]. “Academy”, Moscow, 2003. 208 p. [In Russ].

4. Sanakulov K. Razrabotka biokolloidnoy tekhnologii obezvrezhivaniya tsianidov v khvostovykh pul’pakh zoloto izvlekatel’nykh fabrik [Development of biocolloidal technology for neutralization of cyanides in tail pulps of gold extraction factories] author. dis. .. cand. tech. sciences. Tashkent, 2001. 27 p. [In Russ].

5. Sanakulov U. K., Tazhibaev D.Yu. “Method for processing acidic waste solutions of the biooxidation process of sulfide flotation concentrates.” Utility model patent FAP 03129 dated 05.06.2018. [In Russ].

6. Lobanov D. Z., Vernikova L. M. Mikrobiologicheskoye vyshchelachivaniye metallov: uchebnoye posobiye [Microbiological leaching of metals: textbook]. Moscow Geological Prospecting Institute, Moscow, 2006. 192 p. [In Russ].

7. Vapoev Kh.M., Tagaev I. A., Khusenov K.Sh., Tokhirova N. B. Study of the nature and degree of solubility of some elements in the composition of sulfide ores. Gorniy vestnik Uzbekistan. 2019, no. 2. Pp. 71—75. [In Russ].

8. Goldfarb R. J., Taylor R. D., Collins G. S., Goryachev N. A. Orlandini O. F. Phanerozoic continental growth and gold metallogeny of Asia. Gondwana Research. 2014, Vol. 25, no. 1. Pр. 48–102.

9. Adamov E. V., Panin V. V. Biotekhnologiya metallov: kurs lektsiy [Biotechnology of metals: a course of lectures]. Publishing House “MISiS”, Moscow, 2008. 150 p. [In Russ].

10. Meretukov M. A. Zoloto: khimiya, mineralogiya, metallurgiya: monografiya [Gold: chemistry, mineralogy, metallurgy: monograph]. “Ore and Metals”, Moscow, 2008. 528 p. [In Russ].

11. Avdokhin V. M. Osnovy obogashcheniya poleznykh iskopayemykh. Tom 2. Tekhnologii obogashcheniya poleznykh iskopayemykh: uchebnik [Basics of mineral processing. Vol. 2. Technologies of mineral processing: textbook]. Publishing house of “Moscow State Mining University”, Moscow, 2014. 310 p. [In Russ].

12. Sanakulov K. S., Sagdieva M. G., Tagaev I. A. Biotekhnologicheskiye protsessy v metallurgii. (Biogidrometallurgiya): uchebnoye posobiye [Biotechnological processes in metallurgy. (Biohydrometallurgy): textbook]. “Muharrir”, Tashkent, 2019. Pp. 118—124. [In Russ].